Multiscale analysis of restoration priorities for marine shoreline planning.

PubMed

Diefenderfer, Heida L; Sobocinski, Kathryn L; Thom, Ronald M; May, Christopher W; Borde, Amy B; Southard, Susan L; Vavrinec, John; Sather, Nichole K

2009-10-01

Planners are being called on to prioritize marine shorelines for conservation status and restoration action. This study documents an approach to determining the management strategy most likely to succeed based on current conditions at local and landscape scales. The conceptual framework based in restoration ecology pairs appropriate restoration strategies with sites based on the likelihood of producing long-term resilience given the condition of ecosystem structures and processes at three scales: the shorezone unit (site), the drift cell reach (nearshore marine landscape), and the watershed (terrestrial landscape). The analysis is structured by a conceptual ecosystem model that identifies anthropogenic impacts on targeted ecosystem functions. A scoring system, weighted by geomorphic class, is applied to available spatial data for indicators of stress and function using geographic information systems. This planning tool augments other approaches to prioritizing restoration, including historical conditions and change analysis and ecosystem valuation.

Assessment of the impact of increased solar ultraviolet radiation upon marine ecosystems

NASA Technical Reports Server (NTRS)

Vandyke, H.; Worrest, R. C.

1976-01-01

Data was provided to assess the potential impact upon marine ecosystems if space shuttle operations contribute to a reduction of the stratospheric ozone layer. The potential for irreversible damage to the productivity, structure and/or functioning of a model estuarine ecosystem by increased UV-B radiation was established. The sensitivity of key community components (the primary producers) to increased UV-B radiation was delineated.

Incorporating surrogate species and seascape connectivity to improve marine conservation outcomes.

PubMed

Olds, Andrew D; Connolly, Rod M; Pitt, Kylie A; Maxwell, Paul S; Aswani, Shankar; Albert, Simon

2014-08-01

Conservation focuses on maintaining biodiversity and ecosystem functioning, but gaps in our knowledge of species biology and ecological processes often impede progress. For this reason, focal species and habitats are used as surrogates for multispecies conservation, but species-based approaches are not widely adopted in marine ecosystems. Reserves in the Solomon Islands were designed on the basis of local ecological knowledge to conserve bumphead parrotfish (Bolbometopon muricatum) and to protect food security and ecosystem functioning. Bumphead parrotfish are an iconic threatened species and may be a useful surrogate for multispecies conservation. They move across tropical seascapes throughout their life history, in a pattern of habitat use that is shared with many other species. We examined their value as a conservation surrogate and assessed the importance of seascape connectivity (i.e., the physical connectedness of patches in the seascape) among reefs, mangroves, and seagrass to marine reserve performance. Reserves were designed for bumphead parrotfish, but also enhanced the abundance of other species. Integration of local ecological knowledge and seascape connectivity enhanced the abundance of 17 other harvested fish species in local reserves. This result has important implications for ecosystem functioning and local villagers because many of these species perform important ecological processes and provide the foundation for extensive subsistence fisheries. Our findings suggest greater success in maintaining and restoring marine ecosystems may be achieved when they are managed to conserve surrogate species and preserve functional seascape connections. © 2014 Society for Conservation Biology.

Ecosystem services sustainability in the Mediterranean Sea: assessment of status and trends using multiple modelling approaches

NASA Astrophysics Data System (ADS)

Liquete, Camino; Piroddi, Chiara; Macías, Diego; Druon, Jean-Noël; Zulian, Grazia

2016-09-01

Mediterranean ecosystems support important processes and functions that bring direct benefits to human society. Yet, marine ecosystem services are usually overlooked due to the challenges in identifying and quantifying them. This paper proposes the application of several biophysical and ecosystem modelling approaches to assess spatially and temporally the sustainable use and supply of selected marine ecosystem services. Such services include food provision, water purification, coastal protection, lifecycle maintenance and recreation, focusing on the Mediterranean region. Overall, our study found a higher number of decreasing than increasing trends in the natural capacity of the ecosystems to provide marine and coastal services, while in contrast the opposite was observed to be true for the realised flow of services to humans. Such a study paves the way towards an effective support for Blue Growth and the European maritime policies, although little attention is paid to the quantification of marine ecosystem services in this context. We identify a key challenge of integrating biophysical and socio-economic models as a necessary step to further this research.

Ecosystem services sustainability in the Mediterranean Sea: assessment of status and trends using multiple modelling approaches

PubMed Central

Liquete, Camino; Piroddi, Chiara; Macías, Diego; Druon, Jean-Noël; Zulian, Grazia

2016-01-01

Mediterranean ecosystems support important processes and functions that bring direct benefits to human society. Yet, marine ecosystem services are usually overlooked due to the challenges in identifying and quantifying them. This paper proposes the application of several biophysical and ecosystem modelling approaches to assess spatially and temporally the sustainable use and supply of selected marine ecosystem services. Such services include food provision, water purification, coastal protection, lifecycle maintenance and recreation, focusing on the Mediterranean region. Overall, our study found a higher number of decreasing than increasing trends in the natural capacity of the ecosystems to provide marine and coastal services, while in contrast the opposite was observed to be true for the realised flow of services to humans. Such a study paves the way towards an effective support for Blue Growth and the European maritime policies, although little attention is paid to the quantification of marine ecosystem services in this context. We identify a key challenge of integrating biophysical and socio-economic models as a necessary step to further this research. PMID:27686533

Predator and prey biodiversity relationship and its consequences on marine ecosystem functioning-interplay between nanoflagellates and bacterioplankton.

PubMed

Yang, Jinny Wu; Wu, Wenxue; Chung, Chih-Ching; Chiang, Kuo-Ping; Gong, Gwo-Ching; Hsieh, Chih-Hao

2018-06-01

The importance of biodiversity effects on ecosystem functioning across trophic levels, especially via predatory-prey interactions, is receiving increased recognition. However, this topic has rarely been explored for marine microbes, even though microbial biodiversity contributes significantly to marine ecosystem function and energy flows. Here we examined diversity and biomass of bacteria (prey) and nanoflagellates (predators), as well as their effects on trophic transfer efficiency in the East China Sea. Specifically, we investigated: (i) predator diversity effects on prey biomass and trophic transfer efficiency (using the biomass ratio of predator/prey as a proxy), (ii) prey diversity effects on predator biomass and trophic transfer efficiency, and (iii) the relationship between predator and prey diversity. We found higher prey diversity enhanced both diversity and biomass of predators, as well as trophic transfer efficiency, which may arise from more balanced diet and/or enhanced niche complementarity owing to higher prey diversity. By contrast, no clear effect was detected for predator diversity on prey biomass and transfer efficiency. Notably, we found prey diversity effects on predator-prey interactions; whereas, we found no significant diversity effect on biomass within the same trophic level. Our findings highlight the importance of considering multi-trophic biodiversity effects on ecosystem functioning in natural ecosystems.

Evaluation of mangrove ecosystem service functions of Ximen Island Marine Specially Protected Areas in Yueqing Bay, China

NASA Astrophysics Data System (ADS)

Wang, D. G.; Sun, L.; Tan, Y. H.; Shi, A. Q.; Cheng, J.

2017-08-01

Taking the mangrove ecosystem of Ximen Island National Marine Specially Protected Areas as the research object, the ecological service value of the mangrove forest was evaluated and analyzed using a market value method, an ecological value method and a carbon tax method. The results showed that the ecosystem service value of the mangrove forest on Ximen Island is worth a total of 16,104,000 CNY/a. Among the value of individual ecosystem services, the direct value of material production function and leisure function reached 1,385,000 CNY/a, with a ratio of 8.6%. The indirect value of disturbance regulation, gas regulation, water purification, habitat function and culture research reached 14,719,000 CNY/a, with a ratio of 91.4%. Among the above sub-items, the proportion of disturbance regulation value, habitat function value and cultural research function value reached 78.8%, which reflects the important scientific value and ecological value of the Ximen Island mangrove ecosystem, especially its vital importance in providing a habitat for birds and playing a role in disaster prevention and mitigation.

Impacts of discarded plastic bags on marine assemblages and ecosystem functioning.

PubMed

Green, Dannielle Senga; Boots, Bas; Blockley, David James; Rocha, Carlos; Thompson, Richard

2015-05-05

The accumulation of plastic debris is a global environmental problem due to its durability, persistence, and abundance. Although effects of plastic debris on individual marine organisms, particularly mammals and birds, have been extensively documented (e.g., entanglement and choking), very little is known about effects on assemblages and consequences for ecosystem functioning. In Europe, around 40% of the plastic items produced are utilized as single-use packaging, which rapidly accumulate in waste management facilities and as litter in the environment. A range of biodegradable plastics have been developed with the aspiration of reducing the persistence of litter; however, their impacts on marine assemblages or ecosystem functioning have never been evaluated. A field experiment was conducted to assess the impact of conventional and biodegradable plastic carrier bags as litter on benthic macro- and meio-faunal assemblages and biogeochemical processes (primary productivity, redox condition, organic matter content, and pore-water nutrients) on an intertidal shore near Dublin, Ireland. After 9 weeks, the presence of either type of bag created anoxic conditions within the sediment along with reduced primary productivity and organic matter and significantly lower abundances of infaunal invertebrates. This indicates that both conventional and biodegradable bags can rapidly alter marine assemblages and the ecosystem services they provide.

"And DPSIR begat DAPSI(W)R(M)!" - A unifying framework for marine environmental management.

PubMed

Elliott, M; Burdon, D; Atkins, J P; Borja, A; Cormier, R; de Jonge, V N; Turner, R K

2017-05-15

The marine environment is a complex system formed by interactions between ecological structure and functioning, physico-chemical processes and socio-economic systems. An increase in competing marine uses and users requires a holistic approach to marine management which considers the environmental, economic and societal impacts of all activities. If managed sustainably, the marine environment will deliver a range of ecosystem services which lead to benefits for society. In order to understand the complexity of the system, the DPSIR (Driver-Pressure-State-Impact-Response) approach has long been a valuable problem-structuring framework used to assess the causes, consequences and responses to change in a holistic way. Despite DPSIR being used for a long time, there is still confusion over the definition of its terms and so to be appropriate for current marine management, we contend that this confusion needs to be addressed. Our viewpoint advocates that DPSIR should be extended to DAPSI(W)R(M) (pronounced dap-see-worm) in which Drivers of basic human needs require Activities which lead to Pressures. The Pressures are the mechanisms of State change on the natural system which then leads to Impacts (on human Welfare). Those then require Responses (as Measures). Furthermore, because of the complexity of any managed sea area in terms of multiple Activities, there is the need for a linked-DAPSI(W)R(M) framework, and then the connectivity between marine ecosystems and ecosystems in the catchment and further at sea, requires an interlinked, nested-DAPSI(W)R(M) framework to reflect the continuum between adjacent ecosystems. Finally, the unifying framework for integrated marine management is completed by encompassing ecosystem structure and functioning, ecosystem services and societal benefits. Hence, DAPSI(W)R(M) links the socio-ecological system of the effects of changes to the natural system on the human uses and benefits of the marine system. However, to deliver these sustainably in the light of human activities requires a Risk Assessment and Risk Management framework; the ISO-compliant Bow-Tie method is used here as an example. Finally, to secure ecosystem health and economic benefits such as Blue Growth, successful, adaptive and sustainable marine management Responses (as Measures) are delivered using the 10-tenets, a set of facets covering all management disciplines and approaches. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Climate-driven changes in functional biogeography of Arctic marine fish communities

PubMed Central

Primicerio, Raul; Kortsch, Susanne; Aune, Magnus; Dolgov, Andrey V.; Fossheim, Maria; Aschan, Michaela M.

2017-01-01

Climate change triggers poleward shifts in species distribution leading to changes in biogeography. In the marine environment, fish respond quickly to warming, causing community-wide reorganizations, which result in profound changes in ecosystem functioning. Functional biogeography provides a framework to address how ecosystem functioning may be affected by climate change over large spatial scales. However, there are few studies on functional biogeography in the marine environment, and none in the Arctic, where climate-driven changes are most rapid and extensive. We investigated the impact of climate warming on the functional biogeography of the Barents Sea, which is characterized by a sharp zoogeographic divide separating boreal from Arctic species. Our unique dataset covered 52 fish species, 15 functional traits, and 3,660 stations sampled during the recent warming period. We found that the functional traits characterizing Arctic fish communities, mainly composed of small-sized bottom-dwelling benthivores, are being rapidly replaced by traits of incoming boreal species, particularly the larger, longer lived, and more piscivorous species. The changes in functional traits detected in the Arctic can be predicted based on the characteristics of species expected to undergo quick poleward shifts in response to warming. These are the large, generalist, motile species, such as cod and haddock. We show how functional biogeography can provide important insights into the relationship between species composition, diversity, ecosystem functioning, and environmental drivers. This represents invaluable knowledge in a period when communities and ecosystems experience rapid climate-driven changes across biogeographical regions. PMID:29087943

Impacts of climate change on marine organisms and ecosystems.

PubMed

Brierley, Andrew S; Kingsford, Michael J

2009-07-28

Human activities are releasing gigatonnes of carbon to the Earth's atmosphere annually. Direct consequences of cumulative post-industrial emissions include increasing global temperature, perturbed regional weather patterns, rising sea levels, acidifying oceans, changed nutrient loads and altered ocean circulation. These and other physical consequences are affecting marine biological processes from genes to ecosystems, over scales from rock pools to ocean basins, impacting ecosystem services and threatening human food security. The rates of physical change are unprecedented in some cases. Biological change is likely to be commensurately quick, although the resistance and resilience of organisms and ecosystems is highly variable. Biological changes founded in physiological response manifest as species range-changes, invasions and extinctions, and ecosystem regime shifts. Given the essential roles that oceans play in planetary function and provision of human sustenance, the grand challenge is to intervene before more tipping points are passed and marine ecosystems follow less-buffered terrestrial systems further down a spiral of decline. Although ocean bioengineering may alleviate change, this is not without risk. The principal brake to climate change remains reduced CO(2) emissions that marine scientists and custodians of the marine environment can lobby for and contribute to. This review describes present-day climate change, setting it in context with historical change, considers consequences of climate change for marine biological processes now and in to the future, and discusses contributions that marine systems could play in mitigating the impacts of global climate change.

Biogeochemical significance of pelagic ecosystem function: an end-Cretaceous case study

PubMed Central

Penman, Donald E.; Rae, James W. B.

2016-01-01

Pelagic ecosystem function is integral to global biogeochemical cycling, and plays a major role in modulating atmospheric CO2 concentrations (pCO2). Uncertainty as to the effects of human activities on marine ecosystem function hinders projection of future atmospheric pCO2. To this end, events in the geological past can provide informative case studies in the response of ecosystem function to environmental and ecological changes. Around the Cretaceous–Palaeogene (K–Pg) boundary, two such events occurred: Deccan large igneous province (LIP) eruptions and massive bolide impact at the Yucatan Peninsula. Both perturbed the environment, but only the impact coincided with marine mass extinction. As such, we use these events to directly contrast the response of marine biogeochemical cycling to environmental perturbation with and without changes in global species richness. We measure this biogeochemical response using records of deep-sea carbonate preservation. We find that Late Cretaceous Deccan volcanism prompted transient deep-sea carbonate dissolution of a larger magnitude and timescale than predicted by geochemical models. Even so, the effect of volcanism on carbonate preservation was slight compared with bolide impact. Empirical records and geochemical models support a pronounced increase in carbonate saturation state for more than 500 000 years following the mass extinction of pelagic carbonate producers at the K–Pg boundary. These examples highlight the importance of pelagic ecosystems in moderating climate and ocean chemistry. PMID:27114586

The up-scaling of ecosystem functions in a heterogeneous world

NASA Astrophysics Data System (ADS)

Lohrer, Andrew M.; Thrush, Simon F.; Hewitt, Judi E.; Kraan, Casper

2015-05-01

Earth is in the midst of a biodiversity crisis that is impacting the functioning of ecosystems and the delivery of valued goods and services. However, the implications of large scale species losses are often inferred from small scale ecosystem functioning experiments with little knowledge of how the dominant drivers of functioning shift across scales. Here, by integrating observational and manipulative experimental field data, we reveal scale-dependent influences on primary productivity in shallow marine habitats, thus demonstrating the scalability of complex ecological relationships contributing to coastal marine ecosystem functioning. Positive effects of key consumers (burrowing urchins, Echinocardium cordatum) on seafloor net primary productivity (NPP) elucidated by short-term, single-site experiments persisted across multiple sites and years. Additional experimentation illustrated how these effects amplified over time, resulting in greater primary producer biomass sediment chlorophyll a content (Chla) in the longer term, depending on climatic context and habitat factors affecting the strengths of mutually reinforcing feedbacks. The remarkable coherence of results from small and large scales is evidence of real-world ecosystem function scalability and ecological self-organisation. This discovery provides greater insights into the range of responses to broad-scale anthropogenic stressors in naturally heterogeneous environmental settings.

The up-scaling of ecosystem functions in a heterogeneous world

PubMed Central

Lohrer, Andrew M.; Thrush, Simon F.; Hewitt, Judi E.; Kraan, Casper

2015-01-01

Earth is in the midst of a biodiversity crisis that is impacting the functioning of ecosystems and the delivery of valued goods and services. However, the implications of large scale species losses are often inferred from small scale ecosystem functioning experiments with little knowledge of how the dominant drivers of functioning shift across scales. Here, by integrating observational and manipulative experimental field data, we reveal scale-dependent influences on primary productivity in shallow marine habitats, thus demonstrating the scalability of complex ecological relationships contributing to coastal marine ecosystem functioning. Positive effects of key consumers (burrowing urchins, Echinocardium cordatum) on seafloor net primary productivity (NPP) elucidated by short-term, single-site experiments persisted across multiple sites and years. Additional experimentation illustrated how these effects amplified over time, resulting in greater primary producer biomass sediment chlorophyll a content (Chla) in the longer term, depending on climatic context and habitat factors affecting the strengths of mutually reinforcing feedbacks. The remarkable coherence of results from small and large scales is evidence of real-world ecosystem function scalability and ecological self-organisation. This discovery provides greater insights into the range of responses to broad-scale anthropogenic stressors in naturally heterogeneous environmental settings. PMID:25993477

Marine fisheries declines viewed upside down: human impacts on consumer-driven nutrient recycling.

PubMed

Layman, Craig A; Allgeier, Jacob E; Rosemond, Amy D; Dahlgren, Craig P; Yeager, Lauren A

2011-03-01

We quantified how two human impacts (overfishing and habitat fragmentation) in nearshore marine ecosystems may affect ecosystem function by altering the role of fish as nutrient vectors. We empirically quantified size-specific excretion rates of one of the most abundant fishes (gray snapper, Lutjanus griseus) in The Bahamas and combined these with surveys of fish abundance to estimate population-level excretion rates. The study was conducted across gradients of two human disturbances: overfishing and ecosystem fragmentation (estuaries bisected by roads), to evaluate how each could result in reduced population-level nutrient cycling by consumers. Mean estimated N and P excretion rates for gray snapper populations were on average 456% and 541% higher, respectively, in unfished sites. Ecosystem fragmentation resulted in significant reductions of recycling rates by snapper, with degree of creek fragmentation explaining 86% and 72% of the variance in estimated excretion for dissolved N and P, respectively. Additionally, we used nutrient limitation assays and primary producer nutrient content to provide a simple example of how marine fishery declines may affect primary production. This study provides an initial step toward integrating marine fishery declines and consumer-driven nutrient recycling to more fully understand the implications of human impacts in marine ecosystems.

Climate-driven changes in functional biogeography of Arctic marine fish communities.

PubMed

Frainer, André; Primicerio, Raul; Kortsch, Susanne; Aune, Magnus; Dolgov, Andrey V; Fossheim, Maria; Aschan, Michaela M

2017-11-14

Climate change triggers poleward shifts in species distribution leading to changes in biogeography. In the marine environment, fish respond quickly to warming, causing community-wide reorganizations, which result in profound changes in ecosystem functioning. Functional biogeography provides a framework to address how ecosystem functioning may be affected by climate change over large spatial scales. However, there are few studies on functional biogeography in the marine environment, and none in the Arctic, where climate-driven changes are most rapid and extensive. We investigated the impact of climate warming on the functional biogeography of the Barents Sea, which is characterized by a sharp zoogeographic divide separating boreal from Arctic species. Our unique dataset covered 52 fish species, 15 functional traits, and 3,660 stations sampled during the recent warming period. We found that the functional traits characterizing Arctic fish communities, mainly composed of small-sized bottom-dwelling benthivores, are being rapidly replaced by traits of incoming boreal species, particularly the larger, longer lived, and more piscivorous species. The changes in functional traits detected in the Arctic can be predicted based on the characteristics of species expected to undergo quick poleward shifts in response to warming. These are the large, generalist, motile species, such as cod and haddock. We show how functional biogeography can provide important insights into the relationship between species composition, diversity, ecosystem functioning, and environmental drivers. This represents invaluable knowledge in a period when communities and ecosystems experience rapid climate-driven changes across biogeographical regions. Copyright © 2017 the Author(s). Published by PNAS.

Thirty year ecosystem trajectories in a submerged marine cave under changing pressure regime.

PubMed

Montefalcone, Monica; De Falco, Giada; Nepote, Ettore; Canessa, Martina; Bertolino, Marco; Bavestrello, Giorgio; Morri, Carla; Bianchi, Carlo Nike

2018-06-01

Marine caves are unique and vulnerable habitats exhibiting high biodiversity and heterogeneity, but threatened by multiple global and local disturbances. Marine caves, although widely distributed along the Mediterranean coast, suffer for the lack of quantitative data on their structure and function, which hinder their conservation status assessment. Thanks to the availability of a nearly 30-year-long series of data (1986-2013), we evaluated ecosystem change in the Bergeggi marine cave (Ligurian Sea, NW Mediterranean), a cave with a complex shape and high habitat heterogeneity. Non-taxonomic descriptors were adopted, namely growth forms (GF) and trophic guilds (TG), which are informative about ecosystem structure and functioning, respectively. The cave experienced a general trend of change during the last three decades, mainly due to the decline in the cover of sessile organisms (especially 3-dimensional forms) matched by an increase of turf and sediment, thus causing the structural and functional homogenization of the cave community. While change before 2004 had been attributed to climatic factors (especially to the summer heat waves of 1999 and 2003), the most important rate of change was observed between 2009 and 2013, coinciding with recent major beach nourishments and the extension of the neighbouring Vado Ligure harbour, thus providing evidences on the importance of local disturbances deriving from coastal interventions. Monitoring the status of cave ecosystems is urgently needed, and the use of effective indicators, such as the specific traits here adopted (morphology and feeding strategy), could provide effective tools to assist marine cave conservation. Copyright © 2018 Elsevier Ltd. All rights reserved.

Resilience and stability of a pelagic marine ecosystem

PubMed Central

Lindegren, Martin; Checkley, David M.; Ohman, Mark D.; Koslow, J. Anthony; Goericke, Ralf

2016-01-01

The accelerating loss of biodiversity and ecosystem services worldwide has accentuated a long-standing debate on the role of diversity in stabilizing ecological communities and has given rise to a field of research on biodiversity and ecosystem functioning (BEF). Although broad consensus has been reached regarding the positive BEF relationship, a number of important challenges remain unanswered. These primarily concern the underlying mechanisms by which diversity increases resilience and community stability, particularly the relative importance of statistical averaging and functional complementarity. Our understanding of these mechanisms relies heavily on theoretical and experimental studies, yet the degree to which theory adequately explains the dynamics and stability of natural ecosystems is largely unknown, especially in marine ecosystems. Using modelling and a unique 60-year dataset covering multiple trophic levels, we show that the pronounced multi-decadal variability of the Southern California Current System (SCCS) does not represent fundamental changes in ecosystem functioning, but a linear response to key environmental drivers channelled through bottom-up and physical control. Furthermore, we show strong temporal asynchrony between key species or functional groups within multiple trophic levels caused by opposite responses to these drivers. We argue that functional complementarity is the primary mechanism reducing community variability and promoting resilience and stability in the SCCS. PMID:26763697

Do Behavioral Foraging Responses of Prey to Predators Function Similarly in Restored and Pristine Foodwebs?

PubMed Central

Madin, Elizabeth M. P.; Gaines, Steven D.; Madin, Joshua S.; Link, Anne-Katrin; Lubchenco, Peggy J.; Selden, Rebecca L.; Warner, Robert R.

2012-01-01

Efforts to restore top predators in human-altered systems raise the question of whether rebounds in predator populations are sufficient to restore pristine foodweb dynamics. Ocean ecosystems provide an ideal system to test this question. Removal of fishing in marine reserves often reverses declines in predator densities and size. However, whether this leads to restoration of key functional characteristics of foodwebs, especially prey foraging behavior, is unclear. The question of whether restored and pristine foodwebs function similarly is nonetheless critically important for management and restoration efforts. We explored this question in light of one important determinant of ecosystem function and structure – herbivorous prey foraging behavior. We compared these responses for two functionally distinct herbivorous prey fishes (the damselfish Plectroglyphidodon dickii and the parrotfish Chlorurus sordidus) within pairs of coral reefs in pristine and restored ecosystems in two regions of these species' biogeographic ranges, allowing us to quantify the magnitude and temporal scale of this key ecosystem variable's recovery. We demonstrate that restoration of top predator abundances also restored prey foraging excursion behaviors to a condition closely resembling those of a pristine ecosystem. Increased understanding of behavioral aspects of ecosystem change will greatly improve our ability to predict the cascading consequences of conservation tools aimed at ecological restoration, such as marine reserves. PMID:22403650

Size, sex and individual-level behaviour drive intrapopulation variation in cross-ecosystem foraging of a top-predator.

PubMed

Nifong, James C; Layman, Craig A; Silliman, Brian R

2015-01-01

Large-bodied, top-predators are often highly mobile, with the potential to provide important linkages between spatially distinct food webs. What biological factors contribute to variation in cross-ecosystem movements, however, have rarely been examined. Here, we investigated how ontogeny (body size), sex and individual-level behaviour impacts intrapopulation variation in cross-ecosystem foraging (i.e. between freshwater and marine systems), by the top-predator Alligator mississippiensis. Field surveys revealed A. mississippiensis uses marine ecosystems regularly and are abundant in estuarine tidal creeks (from 0·3 to 6·3 individuals per km of creek, n = 45 surveys). Alligator mississippiensis captured in marine/estuarine habitats were significantly larger than individuals captured in freshwater and intermediate habitats. Stomach content analysis (SCA) showed that small juveniles consumed marine/estuarine prey less frequently (6·7% of individuals) than did large juveniles (57·8%), subadult (73%), and adult (78%) size classes. Isotopic mixing model analysis (SIAR) also suggests substantial variation in use of marine/estuarine prey resources with differences among and within size classes between sexes and individuals (range of median estimates for marine/estuarine diet contribution = 0·05-0·76). These results demonstrate the importance of intrapopulation characteristics (body size, sex and individual specialization) as key determinants of the strength of predator-driven ecosystem connectivity resulting from cross-ecosystem foraging behaviours. Understanding the factors, which contribute to variation in cross-ecosystem foraging behaviours, will improve our predictive understanding of the effects of top-predators on community structure and ecosystem function. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

Effects of acidification on olfactory-mediated behaviour in freshwater and marine ecosystems: a synthesis

PubMed Central

Leduc, Antoine O. H. C.; Munday, Philip L.; Brown, Grant E.; Ferrari, Maud C. O.

2013-01-01

For many aquatic organisms, olfactory-mediated behaviour is essential to the maintenance of numerous fitness-enhancing activities, including foraging, reproduction and predator avoidance. Studies in both freshwater and marine ecosystems have demonstrated significant impacts of anthropogenic acidification on olfactory abilities of fish and macroinvertebrates, leading to impaired behavioural responses, with potentially far-reaching consequences to population dynamics and community structure. Whereas the ecological impacts of impaired olfactory-mediated behaviour may be similar between freshwater and marine ecosystems, the underlying mechanisms are quite distinct. In acidified freshwater, molecular change to chemical cues along with reduced olfaction sensitivity appear to be the primary causes of olfactory-mediated behavioural impairment. By contrast, experiments simulating future ocean acidification suggest that interference of high CO2 with brain neurotransmitter function is the primary cause for olfactory-mediated behavioural impairment in fish. Different physico-chemical characteristics between marine and freshwater systems are probably responsible for these distinct mechanisms of impairment, which, under globally rising CO2 levels, may lead to strikingly different consequences to olfaction. While fluctuations in pH may occur in both freshwater and marine ecosystems, marine habitat will remain alkaline despite future ocean acidification caused by globally rising CO2 levels. In this synthesis, we argue that ecosystem-specific mechanisms affecting olfaction need to be considered for effective management and conservation practices. PMID:23980246

Effects of acidification on olfactory-mediated behaviour in freshwater and marine ecosystems: a synthesis.

PubMed

Leduc, Antoine O H C; Munday, Philip L; Brown, Grant E; Ferrari, Maud C O

2013-01-01

For many aquatic organisms, olfactory-mediated behaviour is essential to the maintenance of numerous fitness-enhancing activities, including foraging, reproduction and predator avoidance. Studies in both freshwater and marine ecosystems have demonstrated significant impacts of anthropogenic acidification on olfactory abilities of fish and macroinvertebrates, leading to impaired behavioural responses, with potentially far-reaching consequences to population dynamics and community structure. Whereas the ecological impacts of impaired olfactory-mediated behaviour may be similar between freshwater and marine ecosystems, the underlying mechanisms are quite distinct. In acidified freshwater, molecular change to chemical cues along with reduced olfaction sensitivity appear to be the primary causes of olfactory-mediated behavioural impairment. By contrast, experiments simulating future ocean acidification suggest that interference of high CO2 with brain neurotransmitter function is the primary cause for olfactory-mediated behavioural impairment in fish. Different physico-chemical characteristics between marine and freshwater systems are probably responsible for these distinct mechanisms of impairment, which, under globally rising CO2 levels, may lead to strikingly different consequences to olfaction. While fluctuations in pH may occur in both freshwater and marine ecosystems, marine habitat will remain alkaline despite future ocean acidification caused by globally rising CO2 levels. In this synthesis, we argue that ecosystem-specific mechanisms affecting olfaction need to be considered for effective management and conservation practices.

Something's fishy. [Marine epidemics may signal environmental threats from pollutants such as PCBs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raloff, J.

1994-07-02

Marine epidemics may signal environmental threats to the immune system of marine animals such as seals, dolphins and turtles. A number of studies are discussed in this article, with particular emphasis on an ongoing study which makes the connection between marine pollution and the decrease in immune system functioning in harbor seals. The effects on the whole marine ecosystem are discussed.

Emergent Properties Delineate Marine Ecosystem Perturbation and Recovery.

PubMed

Link, Jason S; Pranovi, Fabio; Libralato, Simone; Coll, Marta; Christensen, Villy; Solidoro, Cosimo; Fulton, Elizabeth A

2015-11-01

Whether there are common and emergent patterns from marine ecosystems remains an important question because marine ecosystems provide billions of dollars of ecosystem services to the global community, but face many perturbations with significant consequences. Here, we develop cumulative trophic patterns for marine ecosystems, featuring sigmoidal cumulative biomass (cumB)-trophic level (TL) and 'hockey-stick' production (cumP)-cumB curves. The patterns have a trophodynamic theoretical basis and capitalize on emergent, fundamental, and invariant features of marine ecosystems. These patterns have strong global support, being observed in over 120 marine ecosystems. Parameters from these curves elucidate the direction and magnitude of marine ecosystem perturbation or recovery; if biomass and productivity can be monitored effectively over time, such relations may prove to be broadly useful. Curve parameters are proposed as possible ecosystem thresholds, perhaps to better manage the marine ecosystems of the world. Published by Elsevier Ltd.

The Smithsonian-led Marine Global Earth Observatory (MarineGEO): Proposed Model for a Collaborative Network Linking Marine Biodiversity to Ecosystem Processes

NASA Astrophysics Data System (ADS)

Duffy, J. E.

2016-02-01

Biodiversity - the variety of functional types of organisms - is the engine of marine ecosystem processes, including productivity, nutrient cycling, and carbon sequestration. Biodiversity remains a black box in much of ocean science, despite wide recognition that effectively managing human interactions with marine ecosystems requires understanding both structure and functional consequences of biodiversity. Moreover, the inherent complexity of biological systems puts a premium on data-rich, comparative approaches, which are best met via collaborative networks. The Smithsonian Institution's MarineGEO program links a growing network of partners conducting parallel, comparative research to understand change in marine biodiversity and ecosystems, natural and anthropogenic drivers of that change, and the ecological processes mediating it. The focus is on nearshore, seabed-associated systems where biodiversity and human population are concentrated and interact most, yet which fall through the cracks of existing ocean observing programs. MarineGEO offers a standardized toolbox of research modules that efficiently capture key elements of biological diversity and its importance in ecological processes across a range of habitats. The toolbox integrates high-tech (DNA-based, imaging) and low-tech protocols (diver surveys, rapid assays of consumer activity) adaptable to differing institutional capacity and resources. The model for long-term sustainability involves leveraging in-kind support among partners, adoption of best practices wherever possible, engagement of students and citizen scientists, and benefits of training, networking, and global relevance as incentives for participation. Here I highlight several MarineGEO comparative research projects demonstrating the value of standardized, scalable assays and parallel experiments for measuring fish and invertebrate diversity, recruitment, benthic herbivory and generalist predation, decomposition, and carbon sequestration. Key remaining challenges include consensus on protocols; integration of historical data; data management and access; and informatics. These challenges are common to other fields and prospects for progress in the near future are good.

The positive relationship between ocean acidification and pollution.

PubMed

Zeng, Xiangfeng; Chen, Xijuan; Zhuang, Jie

2015-02-15

Ocean acidification and pollution coexist to exert combined effects on the functions and services of marine ecosystems. Ocean acidification can increase the biotoxicity of heavy metals by altering their speciation and bioavailability. Marine pollutants, such as heavy metals and oils, could decrease the photosynthesis rate and increase the respiration rate of marine organisms as a result of biotoxicity and eutrophication, facilitating ocean acidification to varying degrees. Here we review the complex interactions between ocean acidification and pollution in the context of linkage of multiple stressors to marine ecosystems. The synthesized information shows that pollution-affected respiration acidifies coastal oceans more than the uptake of anthropogenic carbon dioxide. Coastal regions are more vulnerable to the negative impact of ocean acidification due to large influxes of pollutants from terrestrial ecosystems. Ocean acidification and pollution facilitate each other, and thus coastal environmental protection from pollution has a large potential for mitigating acidification risk. Copyright © 2014 Elsevier Ltd. All rights reserved.

Assessment of the impact of increased solar ultraviolet radiation upon marine ecosystems

NASA Technical Reports Server (NTRS)

Worrest, R. C.; Vandyke, H.

1978-01-01

Reduction of the earth's ozone layer, with a resultant increase in transmission of solar ultraviolet radiation in the 290 to 320nm waveband (UV-B), via space shuttle operations through the stratosphere is considered. It is shown that simulated solar ultraviolet radiation can, under experimental conditions, detrimentally affect the marine organisms that form the base of the food web of oceanic and estuarine ecosystems. Whether a small increase in biologically harmful ultraviolet radiation might overwhelm these mechanisms and produce changes that will have damaging consequences to the biosphere is discussed. The potential for irreversible damage to the productivity, structure and/or functioning of a model estuarine ecosystem by increased UV-B radiation and whether these ecosystems are highly stable or amenable to adaptive change is studied. Data are provided to assess the potential impact upon marine ecosystems if space shuttle operations contribute to a reduction of the stratospheric ozone layer and the sensitivity of key community components to increased UV-B radiation is examined.

Modelling plankton ecosystems in the meta-omics era. Are we ready?

PubMed

Stec, Krzysztof Franciszek; Caputi, Luigi; Buttigieg, Pier Luigi; D'Alelio, Domenico; Ibarbalz, Federico Matias; Sullivan, Matthew B; Chaffron, Samuel; Bowler, Chris; Ribera d'Alcalà, Maurizio; Iudicone, Daniele

2017-04-01

Recent progress in applying meta-omics approaches to the study of marine ecosystems potentially allows scientists to study the genetic and functional diversity of plankton at an unprecedented depth and with enhanced precision. However, while a range of persistent technical issues still need to be resolved, a much greater obstacle currently preventing a complete and integrated view of the marine ecosystem is the absence of a clear conceptual framework. Herein, we discuss the knowledge that has thus far been derived from conceptual and statistical modelling of marine plankton ecosystems, and illustrate the potential power of integrated meta-omics approaches in the field. We then propose the use of a semantic framework is necessary to support integrative ecological modelling in the meta-omics era, particularly when having to face the increased interdisciplinarity needed to address global issues related to climate change. Copyright © 2017. Published by Elsevier B.V.

Alternative hypotheses to explain why biodiversity-ecosystem functioning relationships are concave-up in some natural ecosystems but concave-down in manipulative experiments.

PubMed

Mora, Camilo; Danovaro, Roberto; Loreau, Michel

2014-06-25

Recent studies of the relationship between biodiversity and functioning in marine ecosystems have yielded non-saturating patterns that contrast sharply with the results of experimental studies, where ecosystem functioning rapidly saturates with increases in biodiversity. Here we provide a simple theoretical framework of three alternative hypotheses that, individually or combined, are likely to explain this contrast: i) the use of functional richness instead of species richness, ii) an increased production efficiency of species in producing biomass when more ecological interactions are present, and iii) the fact that communities are likely assembled in an ordered succession of species from low to high ecological efficiency. Our results provide theoretical support for concave-up biodiversity-ecosystem functioning relationships in natural ecosystems and confirm that the loss of species can have substantially larger effects on the functioning of natural ecosystems than anticipated from controlled manipulative experiments.

Alternative hypotheses to explain why biodiversity-ecosystem functioning relationships are concave-up in some natural ecosystems but concave-down in manipulative experiments

PubMed Central

Mora, Camilo; Danovaro, Roberto; Loreau, Michel

2014-01-01

Recent studies of the relationship between biodiversity and functioning in marine ecosystems have yielded non-saturating patterns that contrast sharply with the results of experimental studies, where ecosystem functioning rapidly saturates with increases in biodiversity. Here we provide a simple theoretical framework of three alternative hypotheses that, individually or combined, are likely to explain this contrast: i) the use of functional richness instead of species richness, ii) an increased production efficiency of species in producing biomass when more ecological interactions are present, and iii) the fact that communities are likely assembled in an ordered succession of species from low to high ecological efficiency. Our results provide theoretical support for concave-up biodiversity-ecosystem functioning relationships in natural ecosystems and confirm that the loss of species can have substantially larger effects on the functioning of natural ecosystems than anticipated from controlled manipulative experiments. PMID:24962477

Global change in the trophic functioning of marine food webs.

PubMed

Maureaud, Aurore; Gascuel, Didier; Colléter, Mathieu; Palomares, Maria L D; Du Pontavice, Hubert; Pauly, Daniel; Cheung, William W L

2017-01-01

The development of fisheries in the oceans, and other human drivers such as climate warming, have led to changes in species abundance, assemblages, trophic interactions, and ultimately in the functioning of marine food webs. Here, using a trophodynamic approach and global databases of catches and life history traits of marine species, we tested the hypothesis that anthropogenic ecological impacts may have led to changes in the global parameters defining the transfers of biomass within the food web. First, we developed two indicators to assess such changes: the Time Cumulated Indicator (TCI) measuring the residence time of biomass within the food web, and the Efficiency Cumulated Indicator (ECI) quantifying the fraction of secondary production reaching the top of the trophic chain. Then, we assessed, at the large marine ecosystem scale, the worldwide change of these two indicators over the 1950-2010 time-periods. Global trends were identified and cluster analyses were used to characterize the variability of trends between ecosystems. Results showed that the most common pattern over the study period is a global decrease in TCI, while the ECI indicator tends to increase. Thus, changes in species assemblages would induce faster and apparently more efficient biomass transfers in marine food webs. Results also suggested that the main driver of change over that period had been the large increase in fishing pressure. The largest changes occurred in ecosystems where 'fishing down the marine food web' are most intensive.

Tropical marginal seas: priority regions for managing marine biodiversity and ecosystem function.

PubMed

McKinnon, A David; Williams, Alan; Young, Jock; Ceccarelli, Daniela; Dunstan, Piers; Brewin, Robert J W; Watson, Reg; Brinkman, Richard; Cappo, Mike; Duggan, Samantha; Kelley, Russell; Ridgway, Ken; Lindsay, Dhugal; Gledhill, Daniel; Hutton, Trevor; Richardson, Anthony J

2014-01-01

Tropical marginal seas (TMSs) are natural subregions of tropical oceans containing biodiverse ecosystems with conspicuous, valued, and vulnerable biodiversity assets. They are focal points for global marine conservation because they occur in regions where human populations are rapidly expanding. Our review of 11 TMSs focuses on three key ecosystems-coral reefs and emergent atolls, deep benthic systems, and pelagic biomes-and synthesizes, illustrates, and contrasts knowledge of biodiversity, ecosystem function, interaction between adjacent habitats, and anthropogenic pressures. TMSs vary in the extent that they have been subject to human influence-from the nearly pristine Coral Sea to the heavily exploited South China and Caribbean Seas-but we predict that they will all be similarly complex to manage because most span multiple national jurisdictions. We conclude that developing a structured process to identify ecologically and biologically significant areas that uses a set of globally agreed criteria is a tractable first step toward effective multinational and transboundary ecosystem management of TMSs.

Tropical Marginal Seas: Priority Regions for Managing Marine Biodiversity and Ecosystem Function

NASA Astrophysics Data System (ADS)

McKinnon, A. David; Williams, Alan; Young, Jock; Ceccarelli, Daniela; Dunstan, Piers; Brewin, Robert J. W.; Watson, Reg; Brinkman, Richard; Cappo, Mike; Duggan, Samantha; Kelley, Russell; Ridgway, Ken; Lindsay, Dhugal; Gledhill, Daniel; Hutton, Trevor; Richardson, Anthony J.

2014-01-01

Tropical marginal seas (TMSs) are natural subregions of tropical oceans containing biodiverse ecosystems with conspicuous, valued, and vulnerable biodiversity assets. They are focal points for global marine conservation because they occur in regions where human populations are rapidly expanding. Our review of 11 TMSs focuses on three key ecosystems - coral reefs and emergent atolls, deep benthic systems, and pelagic biomes - and synthesizes, illustrates, and contrasts knowledge of biodiversity, ecosystem function, interaction between adjacent habitats, and anthropogenic pressures. TMSs vary in the extent that they have been subject to human influence - from the nearly pristine Coral Sea to the heavily exploited South China and Caribbean Seas - but we predict that they will all be similarly complex to manage because most span multiple national jurisdictions. We conclude that developing a structured process to identify ecologically and biologically significant areas that uses a set of globally agreed criteria is a tractable first step toward effective multinational and transboundary ecosystem management of TMSs.

Submarine canyons represent an essential habitat network for krill hotspots in a Large Marine Ecosystem.

PubMed

Santora, Jarrod A; Zeno, Ramona; Dorman, Jeffrey G; Sydeman, William J

2018-05-15

Submarine canyon systems are ubiquitous features of marine ecosystems, known to support high levels of biodiversity. Canyons may be important to benthic-pelagic ecosystem coupling, but their role in concentrating plankton and structuring pelagic communities is not well known. We hypothesize that at the scale of a large marine ecosystem, canyons provide a critical habitat network, which maintain energy flow and trophic interactions. We evaluate canyon characteristics relative to the distribution and abundance of krill, critically important prey in the California Current Ecosystem. Using a geological database, we conducted a census of canyon locations, evaluated their dimensions, and quantified functional relationships with krill hotspots (i.e., sites of persistently elevated abundance) derived from hydro-acoustic surveys. We found that 76% of krill hotspots occurred within and adjacent to canyons. Most krill hotspots were associated with large shelf-incising canyons. Krill hotspots and canyon dimensions displayed similar coherence as a function of latitude and indicate a potential regional habitat network. The latitudinal migration of many fish, seabirds and mammals may be enhanced by using this canyon-krill network to maintain foraging opportunities. Biogeographic assessments and predictions of krill and krill-predator distributions under climate change may be improved by accounting for canyons in habitat models.

Modelling marine community responses to climate-driven species redistribution to guide monitoring and adaptive ecosystem-based management.

PubMed

Marzloff, Martin Pierre; Melbourne-Thomas, Jessica; Hamon, Katell G; Hoshino, Eriko; Jennings, Sarah; van Putten, Ingrid E; Pecl, Gretta T

2016-07-01

As a consequence of global climate-driven changes, marine ecosystems are experiencing polewards redistributions of species - or range shifts - across taxa and throughout latitudes worldwide. Research on these range shifts largely focuses on understanding and predicting changes in the distribution of individual species. The ecological effects of marine range shifts on ecosystem structure and functioning, as well as human coastal communities, can be large, yet remain difficult to anticipate and manage. Here, we use qualitative modelling of system feedback to understand the cumulative impacts of multiple species shifts in south-eastern Australia, a global hotspot for ocean warming. We identify range-shifting species that can induce trophic cascades and affect ecosystem dynamics and productivity, and evaluate the potential effectiveness of alternative management interventions to mitigate these impacts. Our results suggest that the negative ecological impacts of multiple simultaneous range shifts generally add up. Thus, implementing whole-of-ecosystem management strategies and regular monitoring of range-shifting species of ecological concern are necessary to effectively intervene against undesirable consequences of marine range shifts at the regional scale. Our study illustrates how modelling system feedback with only limited qualitative information about ecosystem structure and range-shifting species can predict ecological consequences of multiple co-occurring range shifts, guide ecosystem-based adaptation to climate change and help prioritise future research and monitoring. © 2016 John Wiley & Sons Ltd.

A multitrophic model to quantify the effects of marine viruses on microbial food webs and ecosystem processes

PubMed Central

Weitz, Joshua S; Stock, Charles A; Wilhelm, Steven W; Bourouiba, Lydia; Coleman, Maureen L; Buchan, Alison; Follows, Michael J; Fuhrman, Jed A; Jover, Luis F; Lennon, Jay T; Middelboe, Mathias; Sonderegger, Derek L; Suttle, Curtis A; Taylor, Bradford P; Frede Thingstad, T; Wilson, William H; Eric Wommack, K

2015-01-01

Viral lysis of microbial hosts releases organic matter that can then be assimilated by nontargeted microorganisms. Quantitative estimates of virus-mediated recycling of carbon in marine waters, first established in the late 1990s, were originally extrapolated from marine host and virus densities, host carbon content and inferred viral lysis rates. Yet, these estimates did not explicitly incorporate the cascade of complex feedbacks associated with virus-mediated lysis. To evaluate the role of viruses in shaping community structure and ecosystem functioning, we extend dynamic multitrophic ecosystem models to include a virus component, specifically parameterized for processes taking place in the ocean euphotic zone. Crucially, we are able to solve this model analytically, facilitating evaluation of model behavior under many alternative parameterizations. Analyses reveal that the addition of a virus component promotes the emergence of complex communities. In addition, biomass partitioning of the emergent multitrophic community is consistent with well-established empirical norms in the surface oceans. At steady state, ecosystem fluxes can be probed to characterize the effects that viruses have when compared with putative marine surface ecosystems without viruses. The model suggests that ecosystems with viruses will have (1) increased organic matter recycling, (2) reduced transfer to higher trophic levels and (3) increased net primary productivity. These model findings support hypotheses that viruses can have significant stimulatory effects across whole-ecosystem scales. We suggest that existing efforts to predict carbon and nutrient cycling without considering virus effects are likely to miss essential features of marine food webs that regulate global biogeochemical cycles. PMID:25635642

A multitrophic model to quantify the effects of marine viruses on microbial food webs and ecosystem processes.

PubMed

Weitz, Joshua S; Stock, Charles A; Wilhelm, Steven W; Bourouiba, Lydia; Coleman, Maureen L; Buchan, Alison; Follows, Michael J; Fuhrman, Jed A; Jover, Luis F; Lennon, Jay T; Middelboe, Mathias; Sonderegger, Derek L; Suttle, Curtis A; Taylor, Bradford P; Frede Thingstad, T; Wilson, William H; Eric Wommack, K

2015-06-01

Viral lysis of microbial hosts releases organic matter that can then be assimilated by nontargeted microorganisms. Quantitative estimates of virus-mediated recycling of carbon in marine waters, first established in the late 1990s, were originally extrapolated from marine host and virus densities, host carbon content and inferred viral lysis rates. Yet, these estimates did not explicitly incorporate the cascade of complex feedbacks associated with virus-mediated lysis. To evaluate the role of viruses in shaping community structure and ecosystem functioning, we extend dynamic multitrophic ecosystem models to include a virus component, specifically parameterized for processes taking place in the ocean euphotic zone. Crucially, we are able to solve this model analytically, facilitating evaluation of model behavior under many alternative parameterizations. Analyses reveal that the addition of a virus component promotes the emergence of complex communities. In addition, biomass partitioning of the emergent multitrophic community is consistent with well-established empirical norms in the surface oceans. At steady state, ecosystem fluxes can be probed to characterize the effects that viruses have when compared with putative marine surface ecosystems without viruses. The model suggests that ecosystems with viruses will have (1) increased organic matter recycling, (2) reduced transfer to higher trophic levels and (3) increased net primary productivity. These model findings support hypotheses that viruses can have significant stimulatory effects across whole-ecosystem scales. We suggest that existing efforts to predict carbon and nutrient cycling without considering virus effects are likely to miss essential features of marine food webs that regulate global biogeochemical cycles.

Valuing biodiversity and ecosystem services: a useful way to manage and conserve marine resources?

PubMed

Cavanagh, Rachel D; Broszeit, Stefanie; Pilling, Graham M; Grant, Susie M; Murphy, Eugene J; Austen, Melanie C

2016-12-14

Valuation of biodiversity and ecosystem services (ES) is widely recognized as a useful, though often controversial, approach to conservation and management. However, its use in the marine environment, hence evidence of its efficacy, lags behind that in terrestrial ecosystems. This largely reflects key challenges to marine conservation and management such as the practical difficulties in studying the ocean, complex governance issues and the historically-rooted separation of biodiversity conservation and resource management. Given these challenges together with the accelerating loss of marine biodiversity (and threats to the ES that this biodiversity supports), we ask whether valuation efforts for marine ecosystems are appropriate and effective. We compare three contrasting systems: the tropical Pacific, Southern Ocean and UK coastal seas. In doing so, we reveal a diversity in valuation approaches with different rates of progress and success. We also find a tendency to focus on specific ES (often the harvested species) rather than biodiversity. In light of our findings, we present a new conceptual view of valuation that should ideally be considered in decision-making. Accounting for the critical relationships between biodiversity and ES, together with an understanding of ecosystem structure and functioning, will enable the wider implications of marine conservation and management decisions to be evaluated. We recommend embedding valuation within existing management structures, rather than treating it as an alternative or additional mechanism. However, we caution that its uptake and efficacy will be compromised without the ability to develop and share best practice across regions. © 2016 The Authors.

Valuing biodiversity and ecosystem services: a useful way to manage and conserve marine resources?

PubMed Central

Broszeit, Stefanie; Pilling, Graham M.; Grant, Susie M.; Austen, Melanie C.

2016-01-01

Valuation of biodiversity and ecosystem services (ES) is widely recognized as a useful, though often controversial, approach to conservation and management. However, its use in the marine environment, hence evidence of its efficacy, lags behind that in terrestrial ecosystems. This largely reflects key challenges to marine conservation and management such as the practical difficulties in studying the ocean, complex governance issues and the historically-rooted separation of biodiversity conservation and resource management. Given these challenges together with the accelerating loss of marine biodiversity (and threats to the ES that this biodiversity supports), we ask whether valuation efforts for marine ecosystems are appropriate and effective. We compare three contrasting systems: the tropical Pacific, Southern Ocean and UK coastal seas. In doing so, we reveal a diversity in valuation approaches with different rates of progress and success. We also find a tendency to focus on specific ES (often the harvested species) rather than biodiversity. In light of our findings, we present a new conceptual view of valuation that should ideally be considered in decision-making. Accounting for the critical relationships between biodiversity and ES, together with an understanding of ecosystem structure and functioning, will enable the wider implications of marine conservation and management decisions to be evaluated. We recommend embedding valuation within existing management structures, rather than treating it as an alternative or additional mechanism. However, we caution that its uptake and efficacy will be compromised without the ability to develop and share best practice across regions. PMID:27928037

Ecosystem-based analysis of a marine protected area where fisheries and protected species coexist.

PubMed

Espinoza-Tenorio, Alejandro; Montaño-Moctezuma, Gabriela; Espejel, Ileana

2010-04-01

The Gulf of California Biosphere Reserve (UGC&CRDBR) is a Marine Protected Area that was established in 1993 with the aim of preserving biodiversity and remediating environmental impacts. Because remaining vigilant is hard and because regulatory measures are difficult to enforce, harvesting has been allowed to diminish poaching. Useful management strategies have not been implemented, however, and conflicts remain between conservation legislation and the fisheries. We developed a transdisciplinary methodological scheme (pressure-state-response, loop analysis, and Geographic Information System) that includes both protected species and fisheries modeled together in a spatially represented marine ecosystem. We analyzed the response of this marine ecosystem supposing that conservation strategies were successful and that the abundance of protected species had increased. The final aim of this study was to identify ecosystem-level management alternatives capable of diminishing the conflict between conservation measures and fisheries. This methodological integration aimed to understand the functioning of the UGC&CRDBR community as well as to identify implications of conservation strategies such as the recovery of protected species. Our results suggest research hypotheses related to key species that should be protected within the ecosystem, and they point out the importance of considering spatial management strategies. Counterintuitive findings underline the importance of understanding how the community responds to disturbances and the effect of indirect pathways on the abundance of ecosystem constituents. Insights from this research are valuable in defining policies in marine reserves where fisheries and protected species coexist.

Ecosystem-Based Analysis of a Marine Protected Area Where Fisheries and Protected Species Coexist

NASA Astrophysics Data System (ADS)

Espinoza-Tenorio, Alejandro; Montaño-Moctezuma, Gabriela; Espejel, Ileana

2010-04-01

The Gulf of California Biosphere Reserve (UGC&CRDBR) is a Marine Protected Area that was established in 1993 with the aim of preserving biodiversity and remediating environmental impacts. Because remaining vigilant is hard and because regulatory measures are difficult to enforce, harvesting has been allowed to diminish poaching. Useful management strategies have not been implemented, however, and conflicts remain between conservation legislation and the fisheries. We developed a transdisciplinary methodological scheme (pressure-state-response, loop analysis, and Geographic Information System) that includes both protected species and fisheries modeled together in a spatially represented marine ecosystem. We analyzed the response of this marine ecosystem supposing that conservation strategies were successful and that the abundance of protected species had increased. The final aim of this study was to identify ecosystem-level management alternatives capable of diminishing the conflict between conservation measures and fisheries. This methodological integration aimed to understand the functioning of the UGC&CRDBR community as well as to identify implications of conservation strategies such as the recovery of protected species. Our results suggest research hypotheses related to key species that should be protected within the ecosystem, and they point out the importance of considering spatial management strategies. Counterintuitive findings underline the importance of understanding how the community responds to disturbances and the effect of indirect pathways on the abundance of ecosystem constituents. Insights from this research are valuable in defining policies in marine reserves where fisheries and protected species coexist.

Evaluating and ranking the vulnerability of global marine ecosystems to anthropogenic threats.

PubMed

Halpern, Benjamin S; Selkoe, Kimberly A; Micheli, Fiorenza; Kappel, Carrie V

2007-10-01

Marine ecosystems are threatened by a suite of anthropogenic stressors. Mitigating multiple threats is a daunting task, particularly when funding constraints limit the number of threats that can be addressed. Threats are typically assessed and prioritized via expert opinion workshops that often leave no record of the rationale for decisions, making it difficult to update recommendations with new information. We devised a transparent, repeatable, and modifiable method for collecting expert opinion that describes and documents how threats affect marine ecosystems. Experts were asked to assess the functional impact, scale, and frequency of a threat to an ecosystem; the resistance and recovery time of an ecosystem to a threat; and the certainty of these estimates. To quantify impacts of 38 distinct anthropogenic threats on 23 marine ecosystems, we surveyed 135 experts from 19 different countries. Survey results showed that all ecosystems are threatened by at least nine threats and that nine ecosystems are threatened by >90% of existing threats. The greatest threats (highest impact scores) were increasing sea temperature, demersal destructive fishing, and point-source organic pollution. Rocky reef, coral reef, hard-shelf, mangrove, and offshore epipelagic ecosystems were identified as the most threatened. These general results, however, may be partly influenced by the specific expertise and geography of respondents, and should be interpreted with caution. This approach to threat analysis can identify the greatest threats (globally or locally), most widespread threats, most (or least) sensitive ecosystems, most (or least) threatened ecosystems, and other metrics of conservation value. Additionally, it can be easily modified, updated as new data become available, and scaled to local or regional settings, which would facilitate informed and transparent conservation priority setting.

Mass Spectrometry-Based Metabolomics to Elucidate Functions in Marine Organisms and Ecosystems

PubMed Central

Goulitquer, Sophie; Potin, Philippe; Tonon, Thierry

2012-01-01

Marine systems are very diverse and recognized as being sources of a wide range of biomolecules. This review provides an overview of metabolite profiling based on mass spectrometry (MS) approaches in marine organisms and their environments, focusing on recent advances in the field. We also point out some of the technical challenges that need to be overcome in order to increase applications of metabolomics in marine systems, including extraction of chemical compounds from different matrices and data management. Metabolites being important links between genotype and phenotype, we describe added value provided by integration of data from metabolite profiling with other layers of omics, as well as their importance for the development of systems biology approaches in marine systems to study several biological processes, and to analyze interactions between organisms within communities. The growing importance of MS-based metabolomics in chemical ecology studies in marine ecosystems is also illustrated. PMID:22690147

Causes and projections of abrupt climate-driven ecosystem shifts in the North Atlantic.

PubMed

Beaugrand, Grégory; Edwards, Martin; Brander, Keith; Luczak, Christophe; Ibanez, Frederic

2008-11-01

Warming of the global climate is now unequivocal and its impact on Earth' functional units has become more apparent. Here, we show that marine ecosystems are not equally sensitive to climate change and reveal a critical thermal boundary where a small increase in temperature triggers abrupt ecosystem shifts seen across multiple trophic levels. This large-scale boundary is located in regions where abrupt ecosystem shifts have been reported in the North Atlantic sector and thereby allows us to link these shifts by a global common phenomenon. We show that these changes alter the biodiversity and carrying capacity of ecosystems and may, combined with fishing, precipitate the reduction of some stocks of Atlantic cod already severely impacted by exploitation. These findings offer a way to anticipate major ecosystem changes and to propose adaptive strategies for marine exploited resources such as cod in order to minimize social and economic consequences.

Global change in the trophic functioning of marine food webs

PubMed Central

Gascuel, Didier; Colléter, Mathieu; Palomares, Maria L. D.; Du Pontavice, Hubert; Pauly, Daniel; Cheung, William W. L.

2017-01-01

The development of fisheries in the oceans, and other human drivers such as climate warming, have led to changes in species abundance, assemblages, trophic interactions, and ultimately in the functioning of marine food webs. Here, using a trophodynamic approach and global databases of catches and life history traits of marine species, we tested the hypothesis that anthropogenic ecological impacts may have led to changes in the global parameters defining the transfers of biomass within the food web. First, we developed two indicators to assess such changes: the Time Cumulated Indicator (TCI) measuring the residence time of biomass within the food web, and the Efficiency Cumulated Indicator (ECI) quantifying the fraction of secondary production reaching the top of the trophic chain. Then, we assessed, at the large marine ecosystem scale, the worldwide change of these two indicators over the 1950–2010 time-periods. Global trends were identified and cluster analyses were used to characterize the variability of trends between ecosystems. Results showed that the most common pattern over the study period is a global decrease in TCI, while the ECI indicator tends to increase. Thus, changes in species assemblages would induce faster and apparently more efficient biomass transfers in marine food webs. Results also suggested that the main driver of change over that period had been the large increase in fishing pressure. The largest changes occurred in ecosystems where ‘fishing down the marine food web’ are most intensive. PMID:28800358

Guidance for Protection and Restoration of Nearshore Ecosystems of Puget Sound

DTIC Science & Technology

2004-11-01

marine, watershed, ecosystem process U U U SAR 20 Bernard L. Hargrave 206-764-6839 2 PUGET SOUND...D. L. Bottom, and T. J. Cornwell . 2002. Contrasting functional performance of juvenile salmon in recovering wetlands of the Salmon River estuary

Modelling the interactions between DOM and bacteria in marine ecosystems: state of the art and future prospective

NASA Astrophysics Data System (ADS)

polimene, Luca

2014-05-01

Marine dissolved organic matter (DOM) is the main source of carbon, nutrients and energy for marine prokaryotes, the most abundant life form in the oceans. Only a fraction of assimilated DOM is used by prokaryotes to synthesise new biomass (particulate organic matter, POM), while the rest is used for respiration or is excreted back into the environment as recalcitrant DOM (RDOM). The relative proportions of assimilated DOM that is distributed either to POM, respiration or RDOM is not constant but highly variable depending on the environmental conditions (e.g. nutrient availability, quality/quantity of DOM, temperature). This metabolic plasticity allows bacteria to shape the biogeochemistry of the surrounding waters by modulating three key carbon/energy fluxes fundamental for the functioning of the marine ecosystem: i) the transition from DOM to POM, ii) the remineralisation of carbon and nutrients, and iii) the transformation of labile DOM into recalcitrant DOM. The explicit representation of these processes (and their relative efficiency) in marine ecosystem models is a crucial (and challenging) issue which cannot be overlooked if we want to properly simulate marine biogeochemical cycles under present and climate changing conditions. This talk will provide an overview of how state of the art marine ecosystem models represent the interactions between DOM and bacteria, highlighting strengths and limits of the approaches currently used. A summary of future developments along with issues still open on the topic will also be presented and discussed.

Current status of the East Sea Ecosystem in a changing world

NASA Astrophysics Data System (ADS)

Lee, Sang Heon; Kang, Chang-Keun; Lee, Chung IL; Kwak, Jung Hyun

2017-12-01

The East/Japan Sea (hereafter the East Sea) is changing quickly. Warming and structural changes in the East Sea have been reported by CREAMS, an acronym of ″Circulation Research of the East Asian Marginal Seas″, which began in 1993 as an international research program to understand the water mass structure and circulation in the East Sea (Kim and Kim, 1996; Kim, 1997; Kim et al., 2001, 2002). A subsequent research program of the EAST-I, an acronym of ″the East Asian Seas Time-series″, was launched by PICES (North Pacific Marine Science Organization) and financially supported by the Korean government, allowing us to deepen our knowledge about rapidly changing processes in the East Sea (Chang et al., 2010). Although there has been considerable progress in developing a mechanistic understanding of the East Sea ecosystem responses to disturbances, more comprehensive studies are needed to address the impacts of the frequency and intensity of disturbances on marine ecosystems. The most important question of the research has been: how do environmental changes affect structural and functional biodiversity? Recently launched research on ″Long-term change of structure and function in marine ecosystems of Korea″, which has been supported by the Korean government since 2011, has given an unprecedented insight into the ecosystem dynamics in the East Sea. It therefore seems an appropriate time to devote a special issue to the topic of ″Current status of the East Sea ecosystem in a changing world″.

Marine Arctic Ecosystem Study (MARES) - An Integrated Approach to the Dynamics of the Beaufort Sea

NASA Astrophysics Data System (ADS)

Wiese, F. K.; Gryba, R.; Kelly, B. P.

2016-02-01

MARES is an integrated ecosystem research initiative coordinated and planned by the Bureau of Ocean Energy Management, the Office of Naval Research, the National Aeronautics and Space Administration, the U.S. Coast Guard, and Shell through the National Oceanographic Partnership Program. The overarching goal is to advance our knowledge of the structure and function of the Beaufort Sea marine ecosystem so as to link atmospheric and oceanic drivers to sea ice patterns and marine mammal distribution and availability to local subsistence communities. The study, funded in 2014, focuses on the marine ecosystem along the Beaufort Sea shelf from Barrow, Alaska to the Mackenzie River delta in Canada and is scheduled to include bio-physical moorings along the US-Canadian border, glider deployments packed with bio-physical sensors, tagging of whales and ice-associated seals with satellite CTD-Fluorometer tags, biophysical and chemical cruises including the measurement and characterization of hydrography, ice, nutrients, primary and secondary production, carbon budgets, benthic fauna, fish, as well as analysis of freshwater input and chemical loadings, and ecosystem modeling. This presentation will focus on preliminary results from the ice seal tagging that started in the summer of 2015 and describe some of the planning and possibilities for partnerships for the more comprehensive 2016 field season and beyond.

The Marine Strategy Framework Directive and the ecosystem-based approach – pitfalls and solutions.

PubMed

Berg, Torsten; Fürhaupter, Karin; Teixeira, Heliana; Uusitalo, Laura; Zampoukas, Nikolaos

2015-07-15

The European Marine Strategy Framework Directive aims at good environmental status (GES) in marine waters, following an ecosystem-based approach, focused on 11 descriptors related to ecosystem features, human drivers and pressures. Furthermore, 29 subordinate criteria and 56 attributes are detailed in an EU Commission Decision. The analysis of the Decision and the associated operational indicators revealed ambiguity in the use of terms, such as indicator, impact and habitat and considerable overlap of indicators assigned to various descriptors and criteria. We suggest re-arrangement and elimination of redundant criteria and attributes avoiding double counting in the subsequent indicator synthesis, a clear distinction between pressure and state descriptors and addition of criteria on ecosystem services and functioning. Moreover, we suggest the precautionary principle should be followed for the management of pressures and an evidence-based approach for monitoring state as well as reaching and maintaining GES. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Airborne measurements of multi-wavelength aerosol optical depth and cloud-transmitted radiances in the North Atlantic Aerosols and Marine Ecosystems Study (NAAMES)

NASA Astrophysics Data System (ADS)

Shinozuka, Y.; Johnson, R. R.; LeBlanc, S. E.; Chang, C. S.; Redemann, J.

2016-12-01

We report on our recent airborne measurements of multi-wavelength aerosol optical depth and cloud-transmitted radiances over the North Atlantic. We ran the Spectrometer for Sky-Scanning, Sun-Tracking Atmospheric Research (4STAR) in November 2015 and the 14-channel Ames Airborne Tracking Sunphotometer (AATS-14) in May and June 2016, both aboard the NASA C-130 aircraft. These sunphotometers provide measurements of overlying cirrus and aerosol optical depths of up to about 0.5 and constrain ecosystem and aerosol retrievals from the accompanying nadir-viewing remote sensing instruments. In addition, 4STAR measures hyperspectral transmitted light, which enables the retrieval of cloud optical depth, effective radius, and thermodynamic phase from below cloud. Our measurements contribute to the science objectives of the North Atlantic Aerosols and Marine Ecosystems Study (NAAMES), an interdisciplinary investigation resolving key processes controlling marine ecosystems and aerosols that are essential to our understanding of Earth system function and future change.

Battelle's Marine Research Laboratory, Sequim

DOE Office of Scientific and Technical Information (OSTI.GOV)

Becker, C.D.; Strand, J.A.

Scientists at Battelle's Marine Research Laboratory (MRL) in Sequim, Washington study the effect of human activities on marine ecosystems, with emphasis on near shore and estuarine environments. The laboratory provides research and development assistance to industry and government agencies engaged in management of marine technologies, operation of coastal power utilities, protection of the marine environment, and related areas. This paper outlines and discusses the functions of Battelle's MRL, it's history, it's unique features, it's areas of expertise, it's current programs, and it's cooperating agencies.

Species richness accelerates marine ecosystem restoration in the Coral Triangle.

PubMed

Williams, Susan L; Ambo-Rappe, Rohani; Sur, Christine; Abbott, Jessica M; Limbong, Steven R

2017-11-07

Ecosystem restoration aims to restore biodiversity and valuable functions that have been degraded or lost. The Coral Triangle is a hotspot for marine biodiversity held in its coral reefs, seagrass meadows, and mangrove forests, all of which are in global decline. These coastal ecosystems support valuable fisheries and endangered species, protect shorelines, and are significant carbon stores, functions that have been degraded by coastal development, destructive fishing practices, and climate change. Ecosystem restoration is required to mitigate these damages and losses, but its practice is in its infancy in the region. Here we demonstrate that species diversity can set the trajectory of restoration. In a seagrass restoration experiment in the heart of the Coral Triangle (Sulawesi, Indonesia), plant survival and coverage increased with the number of species transplanted. Our results highlight the positive role biodiversity can play in ecosystem restoration and call for revision of the common restoration practice of establishing a single target species, particularly in regions having high biodiversity. Coastal ecosystems affect human well-being in many important ways, and restoration will become ever more important as conservation efforts cannot keep up with their loss. Published under the PNAS license.

Unexpected Early Triassic marine ecosystem and the rise of the Modern evolutionary fauna.

PubMed

Brayard, Arnaud; Krumenacker, L J; Botting, Joseph P; Jenks, James F; Bylund, Kevin G; Fara, Emmanuel; Vennin, Emmanuelle; Olivier, Nicolas; Goudemand, Nicolas; Saucède, Thomas; Charbonnier, Sylvain; Romano, Carlo; Doguzhaeva, Larisa; Thuy, Ben; Hautmann, Michael; Stephen, Daniel A; Thomazo, Christophe; Escarguel, Gilles

2017-02-01

In the wake of the end-Permian mass extinction, the Early Triassic (~251.9 to 247 million years ago) is portrayed as an environmentally unstable interval characterized by several biotic crises and heavily depauperate marine benthic ecosystems. We describe a new fossil assemblage-the Paris Biota-from the earliest Spathian (middle Olenekian, ~250.6 million years ago) of the Bear Lake area, southeastern Idaho, USA. This highly diversified assemblage documents a remarkably complex marine ecosystem including at least seven phyla and 20 distinct metazoan orders, along with algae. Most unexpectedly, it combines early Paleozoic and middle Mesozoic taxa previously unknown from the Triassic strata, among which are primitive Cambrian-Ordovician leptomitid sponges (a 200-million year Lazarus taxon) and gladius-bearing coleoid cephalopods, a poorly documented group before the Jurassic (~50 million years after the Early Triassic). Additionally, the crinoid and ophiuroid specimens show derived anatomical characters that were thought to have evolved much later. Unlike previous works that suggested a sluggish postcrisis recovery and a low diversity for the Early Triassic benthic organisms, the unexpected composition of this exceptional assemblage points toward an early and rapid post-Permian diversification for these clades. Overall, it illustrates a phylogenetically diverse, functionally complex, and trophically multileveled marine ecosystem, from primary producers up to top predators and potential scavengers. Hence, the Paris Biota highlights the key evolutionary position of Early Triassic fossil ecosystems in the transition from the Paleozoic to the Modern marine evolutionary fauna at the dawn of the Mesozoic era.

[Evaluation of ecosystem service and emergy of Wanshan Waters in Zhuhai, Guangdong Province, China].

PubMed

Qin, Chuan-xin; Chen, Pi-mao; Zhang, An-kai; Yuan, Hua; Li, Guo-ying; Shu, Li-ming; Zhou, Yan-bo; Li, Xiao-guo

2015-06-01

The method for monetary value and emergy value analysis of ecosystem service was used in this paper to analyze the change in value of marine ecosystem service of Wanshan District, Zhuhai from 2007 to 2012. The result showed that the monetary value and emergy value of marine ecosystem service of Wanshan District, Zhuhai rose to 11512840000 yuan and 1.97 x 10(22) sej from 7721630000 yuan and 1.04 x 10(22) sej, respectively. Both monetary value and emergy value could forecast the change in the value of marine ecosystem service, but they reflected different value structures and ecological energy, which could be used to more objectively evaluate the ecosystem service. Ecological civilization development, as an inherent driving force to impel the development of marine ecosystem service structure, was important for rational exploitation of marine resources and optimization of marine ecosystem service.

Quantifying patterns of change in marine ecosystem response to multiple pressures.

PubMed

Large, Scott I; Fay, Gavin; Friedland, Kevin D; Link, Jason S

2015-01-01

The ability to understand and ultimately predict ecosystem response to multiple pressures is paramount to successfully implement ecosystem-based management. Thresholds shifts and nonlinear patterns in ecosystem responses can be used to determine reference points that identify levels of a pressure that may drastically alter ecosystem status, which can inform management action. However, quantifying ecosystem reference points has proven elusive due in large part to the multi-dimensional nature of both ecosystem pressures and ecosystem responses. We used ecological indicators, synthetic measures of ecosystem status and functioning, to enumerate important ecosystem attributes and to reduce the complexity of the Northeast Shelf Large Marine Ecosystem (NES LME). Random forests were used to quantify the importance of four environmental and four anthropogenic pressure variables to the value of ecological indicators, and to quantify shifts in aggregate ecological indicator response along pressure gradients. Anthropogenic pressure variables were critical defining features and were able to predict an average of 8-13% (up to 25-66% for individual ecological indicators) of the variation in ecological indicator values, whereas environmental pressures were able to predict an average of 1-5 % (up to 9-26% for individual ecological indicators) of ecological indicator variation. Each pressure variable predicted a different suite of ecological indicator's variation and the shapes of ecological indicator responses along pressure gradients were generally nonlinear. Threshold shifts in ecosystem response to exploitation, the most important pressure variable, occurred when commercial landings were 20 and 60% of total surveyed biomass. Although present, threshold shifts in ecosystem response to environmental pressures were much less important, which suggests that anthropogenic pressures have significantly altered the ecosystem structure and functioning of the NES LME. Gradient response curves provide ecologically informed transformations of pressure variables to explain patterns of ecosystem structure and functioning. By concurrently identifying thresholds for a suite of ecological indicator responses to multiple pressures, we demonstrate that ecosystem reference points can be evaluated and used to support ecosystem-based management.

75 FR 59645 - Endangered and Threatened Wildlife and Plants; Determination of Endangered Status for the African...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-28

... marine ecosystem of the coast of South Africa and Namibia. The Benguela ecosystem, encompassing one of... (Fennel 1999, p. 177). The Benguela ecosystem is an important center of marine biodiversity and marine... feeding grounds for a variety of marine and avian species. The Benguela ecosystem historically supports a...

Climate change impacts on marine ecosystems.

PubMed

Doney, Scott C; Ruckelshaus, Mary; Duffy, J Emmett; Barry, James P; Chan, Francis; English, Chad A; Galindo, Heather M; Grebmeier, Jacqueline M; Hollowed, Anne B; Knowlton, Nancy; Polovina, Jeffrey; Rabalais, Nancy N; Sydeman, William J; Talley, Lynne D

2012-01-01

In marine ecosystems, rising atmospheric CO2 and climate change are associated with concurrent shifts in temperature, circulation, stratification, nutrient input, oxygen content, and ocean acidification, with potentially wide-ranging biological effects. Population-level shifts are occurring because of physiological intolerance to new environments, altered dispersal patterns, and changes in species interactions. Together with local climate-driven invasion and extinction, these processes result in altered community structure and diversity, including possible emergence of novel ecosystems. Impacts are particularly striking for the poles and the tropics, because of the sensitivity of polar ecosystems to sea-ice retreat and poleward species migrations as well as the sensitivity of coral-algal symbiosis to minor increases in temperature. Midlatitude upwelling systems, like the California Current, exhibit strong linkages between climate and species distributions, phenology, and demography. Aggregated effects may modify energy and material flows as well as biogeochemical cycles, eventually impacting the overall ecosystem functioning and services upon which people and societies depend.

Whale Multi-Disciplinary Studies: A Marine Education Infusion Unit. Northern New England Marine Education Project.

ERIC Educational Resources Information Center

Maine Univ., Orono. Coll. of Education.

This multidisciplinary unit deals with whales, whaling lore and history, and the interaction of the whale with the complex marine ecosystem. It seeks to teach adaptation of marine organisms. It portrays the concept that man is part of the marine ecosystem and man's activities can deplete and degrade marine ecosystems, endangering the survival of…

Large-scale marine ecosystem change and the conservation of marine mammals

USGS Publications Warehouse

O'Shea, T.J.; Odell, D.K.

2008-01-01

Papers in this Special Feature stem from a symposium on large-scale ecosystem change and the conservation of marine mammals convened at the 86th Annual Meeting of the American Society of Mammalogists in June 2006. Major changes are occurring in multiple aspects of the marine environment at unprecedented rates, within the life spans of some individual marine mammals. Drivers of change include shifts in climate, acoustic pollution, disturbances to trophic structure, fisheries interactions, harmful algal blooms, and environmental contaminants. This Special Feature provides an in-depth examination of 3 issues that are particularly troublesome. The 1st article notes the huge spatial and temporal scales of change to which marine mammals are showing ecological responses, and how these species can function as sentinels of such change. The 2nd paper describes the serious problems arising from conflicts with fisheries, and the 3rd contribution reviews the growing issues associated with underwater noise. ?? 2008 American Society of Mammalogists.

Proteorhodopsins: an array of physiological roles?

PubMed

Fuhrman, Jed A; Schwalbach, Michael S; Stingl, Ulrich

2008-06-01

Metagenomic analyses have revealed widespread and diverse retinal-binding rhodopsin proteins (named proteorhodopsins) among numerous marine bacteria and archaea, which has challenged the notion that solar energy can only enter marine ecosystems by chlorophyll-based photosynthesis. Most marine proteorhodopsins share structural and functional similarities with archaeal bacteriorhodopsins, which generate proton motive force via light-activated proton pumping, thereby ultimately powering ATP production. This suggests an energetic role for proteorhodopsins. However, results from a growing number of investigations do not readily fit this model, which indicates that proteorhodopsins could have a range of physiological functions.

Marine birds as indicators of Arctic marine ecosystem health: linking the Northern Ecosystem Initiative to long-term studies.

PubMed

Mallory, Mark L; Gilchrist, H Grant; Braune, Birgit M; Gaston, Anthony J

2006-02-01

Marine birds are sensitive indicators of the condition of marine ecosystems in the Arctic, partly because they feed at the top of the arctic food chain. The Northern Ecosystem Initiative (NEI) recently supported four separate studies that investigated aspects of Arctic marine bird science which simultaneously addressed goals of the NEI to better understand northern ecosystems and their response to environmental stressors. The projects used both scientific and traditional knowledge to examine the relationship between sea-ice, contaminants, and the ecology of marine birds, and to transfer environmental knowledge to students. Results from these investigations confirm that changes are occurring in Arctic environments, and that these are captured through marine bird research. Collectively these studies provided new data that supported NEI objectives of monitoring the health of the Arctic ecosystem, and contributed to Canada's international obligations for Arctic science.

Interdisciplinary knowledge exchange across scales in a globally changing marine environment.

PubMed

McDonald, Karlie S; Hobday, Alistair J; Fulton, Elizabeth A; Thompson, Peter A

2018-07-01

The effects of anthropogenic global environmental change on biotic and abiotic processes have been reported in aquatic systems across the world. Complex synergies between concurrent environmental stressors and the resilience of the system to regime shifts, which vary in space and time, determine the capacity for marine systems to maintain structure and function with global environmental change. Consequently, an interdisciplinary approach that facilitates the development of new methods for the exchange of knowledge between scientists across multiple scales is required to effectively understand, quantify and predict climate impacts on marine ecosystem services. We use a literature review to assess the limitations and assumptions of current pathways to exchange interdisciplinary knowledge and the transferability of research findings across spatial and temporal scales and levels of biological organization to advance scientific understanding of global environmental change in marine systems. We found that species-specific regional scale climate change research is most commonly published, and "supporting" is the ecosystem service most commonly referred to in publications. In addition, our paper outlines a trajectory for the future development of integrated climate change science for sustaining marine ecosystem services such as investment in interdisciplinary education and connectivity between disciplines. © 2018 John Wiley & Sons Ltd.

Effects of pharmaceuticals and personal care products on marine organisms: from single-species studies to an ecosystem-based approach.

PubMed

Prichard, Emma; Granek, Elise F

2016-11-01

Pharmaceuticals and personal care products (PPCPs) are contaminants of emerging concern that are increasing in use and have demonstrated negative effects on aquatic organisms. There is a growing body of literature reporting the effects of PPCPs on freshwater organisms, but studies on the effects of PPCPs to marine and estuarine organisms are limited. Among effect studies, the vast majority examines subcellular or cellular effects, with far fewer studies examining organismal- and community-level effects. We reviewed the current published literature on marine and estuarine algae, invertebrates, fish, and mammals exposed to PPCPs, in order to expand upon current reviews. This paper builds on previous reviews of PPCP contamination in marine environments, filling prior literature gaps and adding consideration of ecosystem function and level of knowledge across marine habitat types. Finally, we reviewed and compiled data gaps suggested by current researchers and reviewers and propose a multi-level model to expand the focus of current PPCP research beyond laboratory studies. This model includes examination of direct ecological effects including food web and disease dynamics, biodiversity, community composition, and other ecosystem-level indicators of contaminant-driven change.

Marine biological diversity: Some important issues, opportunities and critical research needs

NASA Astrophysics Data System (ADS)

Butman, Cheryl Ann; Carlton, James T.

1995-07-01

Marine biological diversity is changing, dramatically in some cases, and most recent changes are due to broad-scale human activities. Knowledge of "biodiversity" — the variety of genomes (the genetic material specifying all characteristics and functions within an organism), species and ecosystems — is the foundation for understanding and predicting how human and natural effects can change the ocean's ecosystems. Evaluating the scale and ultimate consequences to life in the sea of a plethora of anthropogenic effects is difficult, however, because there is inadequate knowledge of both the patterns of and the processes that control marine biodiversity. Recognizing change and evaluating its consequences require sufficient knowledge of present and historical natural patterns of biodiversity, and sufficient understanding of how and why these patterns vary in space and time. Data on biodiversity patterns and their causes are sorely lacking for most marine ecosystems. Adequate understanding of what creates and maintains diversity must be the scientific underpinning for policy decisions regarding pollutant and waste disposal, habitat alteration, fisheries management and the preservation of threatened or endangered species. The inability, at this time, to provide such information to policy makers may have important implications for the conservation of marine life [Norse, 1993].

Species distribution models of two critically endangered deep-sea octocorals reveal fishing impacts on vulnerable marine ecosystems in central Mediterranean Sea.

PubMed

Lauria, V; Garofalo, G; Fiorentino, F; Massi, D; Milisenda, G; Piraino, S; Russo, T; Gristina, M

2017-08-14

Deep-sea coral assemblages are key components of marine ecosystems that generate habitats for fish and invertebrate communities and act as marine biodiversity hot spots. Because of their life history traits, deep-sea corals are highly vulnerable to human impacts such as fishing. They are an indicator of vulnerable marine ecosystems (VMEs), therefore their conservation is essential to preserve marine biodiversity. In the Mediterranean Sea deep-sea coral habitats are associated with commercially important crustaceans, consequently their abundance has dramatically declined due to the effects of trawling. Marine spatial planning is required to ensure that the conservation of these habitats is achieved. Species distribution models were used to investigate the distribution of two critically endangered octocorals (Funiculina quadrangularis and Isidella elongata) in the central Mediterranean as a function of environmental and fisheries variables. Results show that both species exhibit species-specific habitat preferences and spatial patterns in response to environmental variables, but the impact of trawling on their distribution differed. In particular F. quadrangularis can overlap with fishing activities, whereas I. elongata occurs exclusively where fishing is low or absent. This study represents the first attempt to identify key areas for the protection of soft and compact mud VMEs in the central Mediterranean Sea.

Typology and indicators of ecosystem services for marine spatial planning and management.

PubMed

Böhnke-Henrichs, Anne; Baulcomb, Corinne; Koss, Rebecca; Hussain, S Salman; de Groot, Rudolf S

2013-11-30

The ecosystem services concept provides both an analytical and communicative tool to identify and quantify the link between human welfare and the environment, and thus to evaluate the ramifications of management interventions. Marine spatial planning (MSP) and Ecosystem-based Management (EBM) are a form of management intervention that has become increasingly popular and important globally. The ecosystem service concept is rarely applied in marine planning and management to date which we argue is due to the lack of a well-structured, systematic classification and assessment of marine ecosystem services. In this paper we not only develop such a typology but also provide guidance to select appropriate indicators for all relevant ecosystem services. We apply this marine-specific ecosystem service typology to MSP and EBM. We thus provide not only a novel theoretical construct but also show how the ecosystem services concept can be used in marine planning and management. Copyright © 2013 Elsevier Ltd. All rights reserved.

An Ecosystem-Based Approach to Assess the Status of a Mediterranean Ecosystem, the Posidonia oceanica Seagrass Meadow

PubMed Central

Personnic, Sébastien; Boudouresque, Charles F.; Astruch, Patrick; Ballesteros, Enric; Blouet, Sylvain; Bellan-Santini, Denise; Bonhomme, Patrick; Thibault-Botha, Delphine; Feunteun, Eric; Harmelin-Vivien, Mireille; Pergent, Gérard; Pergent-Martini, Christine; Pastor, Jérémy; Poggiale, Jean-Christophe; Renaud, Florent; Thibaut, Thierry; Ruitton, Sandrine

2014-01-01

Biotic indices, which reflect the quality of the environment, are widely used in the marine realm. Sometimes, key species or ecosystem engineers are selected for this purpose. This is the case of the Mediterranean seagrass Posidonia oceanica, widely used as a biological quality element in the context of the European Union Water Framework Directive (WFD). The good quality of a water body and the apparent health of a species, whether or not an ecosystem engineer such as P. oceanica, is not always indicative of the good structure and functioning of the whole ecosystem. A key point of the recent Marine Strategy Framework Directive (MSFD) is the ecosystem-based approach. Here, on the basis of a simplified conceptual model of the P. oceanica ecosystem, we have proposed an ecosystem-based index of the quality of its functioning, compliant with the MSFD requirements. This index (EBQI) is based upon a set of representative functional compartments, the weighting of these compartments and the assessment of the quality of each compartment by comparison of a supposed baseline. The index well discriminated 17 sites in the north-western Mediterranean (French Riviera, Provence, Corsica, Catalonia and Balearic Islands) covering a wide range of human pressure levels. The strong points of the EBQI are that it is easy to implement, non-destructive, relatively robust, according to the selection of the compartments and to their weighting, and associated with confidence indices that indicate possible weakness and biases and therefore the need for further field data acquisition. PMID:24933020

Invasive species: an increasing threat to marine ecosystems under climate change?

NASA Astrophysics Data System (ADS)

Artioli, Yuri; Galienne, Chris; Holt, Jason; Wakelin, Sarah; Butenschön, Momme; Schrum, Corinna; Daewel, Ute; Pushpadas, Dhania; Cannaby, Heather; Salihoglu, Baris; Zavatarelli, Marco; Clementi, Emanuela; Olenin, Sergej; Allen, Icarus

2013-04-01

Planktonic Non-Indigenous Species (NIS) are a potential threat to marine ecosystems: a successful invasion of such organisms can alter significantly the ecosystem structure with shift in species composition that can affect different levels of the trophic network and also with local extinction of native species in the more extreme cases. Such changes will also impact some ecosystem functions like primary and secondary production or nutrient cycling, and services, like fishery, aquaculture or carbon sequestration. Understanding how climate change influences the susceptibility of a marine ecosystem to invasion is challenging as the success and the impact of an invasion depend on many different factors all tightly interconnected (e.g. time of the invasion, location, state of the ecosystem…). Here we present DivERSEM, a new version of the biogeochemical model ERSEM modified in order to account for phytoplankton diversity. With such a model, we are able to simulate invasion from phytoplankton NIS, to assess the likelihood of success of such an invasion and to estimate the potential impact on ecosystem structure, using indicator like the Biopollution index. In the MEECE project (www.meece.eu), the model has been coupled to a 1D water column model (GOTM) in two different climate scenarios (present day and the IPCC SRES A1B scenario for 2100) in 4 different European shelf seas (North Sea, Baltic Sea, Black Sea and Adriatic Sea). The model has been forced with atmospheric data coming from the IPSL climate model, and nutrient concentration extracted from a set of 3D biogeochemical models running under the same climate scenario. The response of the ecosystem susceptibility to invasion to climate change has been analysed comparing the successfulness of invasions in the two time slices and its impact on community structure and ecosystem functions. At the same time, the comparison among the different basins allowed to highlight some of the characteristics that make the ecosystems more vulnerable to NIS.

Multiple stressors, nonlinear effects and the implications of climate change impacts on marine coastal ecosystems.

PubMed

Hewitt, Judi E; Ellis, Joanne I; Thrush, Simon F

2016-08-01

Global climate change will undoubtedly be a pressure on coastal marine ecosystems, affecting not only species distributions and physiology but also ecosystem functioning. In the coastal zone, the environmental variables that may drive ecological responses to climate change include temperature, wave energy, upwelling events and freshwater inputs, and all act and interact at a variety of spatial and temporal scales. To date, we have a poor understanding of how climate-related environmental changes may affect coastal marine ecosystems or which environmental variables are likely to produce priority effects. Here we use time series data (17 years) of coastal benthic macrofauna to investigate responses to a range of climate-influenced variables including sea-surface temperature, southern oscillation indices (SOI, Z4), wind-wave exposure, freshwater inputs and rainfall. We investigate responses from the abundances of individual species to abundances of functional traits and test whether species that are near the edge of their tolerance to another stressor (in this case sedimentation) may exhibit stronger responses. The responses we observed were all nonlinear and some exhibited thresholds. While temperature was most frequently an important predictor, wave exposure and ENSO-related variables were also frequently important and most ecological variables responded to interactions between environmental variables. There were also indications that species sensitive to another stressor responded more strongly to weaker climate-related environmental change at the stressed site than the unstressed site. The observed interactions between climate variables, effects on key species or functional traits, and synergistic effects of additional anthropogenic stressors have important implications for understanding and predicting the ecological consequences of climate change to coastal ecosystems. © 2015 John Wiley & Sons Ltd.

Unexpected Early Triassic marine ecosystem and the rise of the Modern evolutionary fauna

PubMed Central

Brayard, Arnaud; Krumenacker, L. J.; Botting, Joseph P.; Jenks, James F.; Bylund, Kevin G.; Fara, Emmanuel; Vennin, Emmanuelle; Olivier, Nicolas; Goudemand, Nicolas; Saucède, Thomas; Charbonnier, Sylvain; Romano, Carlo; Doguzhaeva, Larisa; Thuy, Ben; Hautmann, Michael; Stephen, Daniel A.; Thomazo, Christophe; Escarguel, Gilles

2017-01-01

In the wake of the end-Permian mass extinction, the Early Triassic (~251.9 to 247 million years ago) is portrayed as an environmentally unstable interval characterized by several biotic crises and heavily depauperate marine benthic ecosystems. We describe a new fossil assemblage—the Paris Biota—from the earliest Spathian (middle Olenekian, ~250.6 million years ago) of the Bear Lake area, southeastern Idaho, USA. This highly diversified assemblage documents a remarkably complex marine ecosystem including at least seven phyla and 20 distinct metazoan orders, along with algae. Most unexpectedly, it combines early Paleozoic and middle Mesozoic taxa previously unknown from the Triassic strata, among which are primitive Cambrian-Ordovician leptomitid sponges (a 200–million year Lazarus taxon) and gladius-bearing coleoid cephalopods, a poorly documented group before the Jurassic (~50 million years after the Early Triassic). Additionally, the crinoid and ophiuroid specimens show derived anatomical characters that were thought to have evolved much later. Unlike previous works that suggested a sluggish postcrisis recovery and a low diversity for the Early Triassic benthic organisms, the unexpected composition of this exceptional assemblage points toward an early and rapid post-Permian diversification for these clades. Overall, it illustrates a phylogenetically diverse, functionally complex, and trophically multileveled marine ecosystem, from primary producers up to top predators and potential scavengers. Hence, the Paris Biota highlights the key evolutionary position of Early Triassic fossil ecosystems in the transition from the Paleozoic to the Modern marine evolutionary fauna at the dawn of the Mesozoic era. PMID:28246643

Biological data assimilation for parameter estimation of a phytoplankton functional type model for the western North Pacific

NASA Astrophysics Data System (ADS)

Hoshiba, Yasuhiro; Hirata, Takafumi; Shigemitsu, Masahito; Nakano, Hideyuki; Hashioka, Taketo; Masuda, Yoshio; Yamanaka, Yasuhiro

2018-06-01

Ecosystem models are used to understand ecosystem dynamics and ocean biogeochemical cycles and require optimum physiological parameters to best represent biological behaviours. These physiological parameters are often tuned up empirically, while ecosystem models have evolved to increase the number of physiological parameters. We developed a three-dimensional (3-D) lower-trophic-level marine ecosystem model known as the Nitrogen, Silicon and Iron regulated Marine Ecosystem Model (NSI-MEM) and employed biological data assimilation using a micro-genetic algorithm to estimate 23 physiological parameters for two phytoplankton functional types in the western North Pacific. The estimation of the parameters was based on a one-dimensional simulation that referenced satellite data for constraining the physiological parameters. The 3-D NSI-MEM optimized by the data assimilation improved the timing of a modelled plankton bloom in the subarctic and subtropical regions compared to the model without data assimilation. Furthermore, the model was able to improve not only surface concentrations of phytoplankton but also their subsurface maximum concentrations. Our results showed that surface data assimilation of physiological parameters from two contrasting observatory stations benefits the representation of vertical plankton distribution in the western North Pacific.

The invasibility of marine algal assemblages: role of functional diversity and identity.

PubMed

Arenas, Francisco; Sánchez, Iñigo; Hawkins, Stephen J; Jenkins, Stuart R

2006-11-01

The emergence of the biodiversity-ecosystem functioning debate in the last decade has renewed interest in understanding why some communities are more easily invaded than others and how the impact of invasion on recipient communities and ecosystems varies. To date most of the research on invasibility has focused on taxonomic diversity, i.e., species richness. However, functional diversity of the communities should be more relevant for the resistance of the community to invasions, as the extent of functional differences among the species in an assemblage is a major determinant of ecosystem processes. Although coastal marine habitats are among the most heavily invaded ecosystems, studies on community invasibility and vulnerability in these habitats are scarce. We carried out a manipulative field experiment in tide pools of the rocky intertidal to test the hypothesis that increasing functional richness reduces the susceptibility of macroalgal communities to invasion. We selected a priori four functional groups on the basis of previous knowledge of local species characteristics: encrusting, turf, subcanopy, and canopy species. Synthetic assemblages containing one, two, three, or four different functional groups of seaweeds were created, and invasion by native species was monitored over an eight-month period. Cover and resource availability in the assemblages with only one functional group showed different patterns in the use of space and light, confirming true functional differences among our groups. Experimental results showed that the identity of functional groups was more important than functional richness in determining the ability of macroalgal communities to resist invasion and that resistance to invasion was resource-mediated.

Marine Socio-Environmental Covariates: queryable global layers of environmental and anthropogenic variables for marine ecosystem studies.

PubMed

Yeager, Lauren A; Marchand, Philippe; Gill, David A; Baum, Julia K; McPherson, Jana M

2017-07-01

Biophysical conditions, including climate, environmental stress, and habitat availability, are key drivers of many ecological processes (e.g., community assembly and productivity) and associated ecosystem services (e.g., carbon sequestration and fishery production). Furthermore, anthropogenic impacts such as coastal development and fishing can have drastic effects on the structure and function of marine ecosystems. Scientists need to account for environmental variation and human impacts to accurately model, manage, and conserve marine ecosystems. Although there are many types of environmental data available from global remote sensing and open-source data products, some are inaccessible to potential end-users because they exist as global layers in high temporal and spatial resolutions which require considerable computational power to process. Additionally, coastal locations often suffer from missing data or data quality issues which limit the utility of some global marine products for coastal sites. Herein we present the Marine Socio-Environmental Covariates dataset for the global oceans, which consists of environmental and anthropogenic variables summarized in ecologically relevant ways. The dataset includes four sets of environmental variables related to biophysical conditions (net primary productivity models corrected for shallow-water reflectance, wave energy including sheltered-coastline corrections) and landscape context (coral reef and land cover within varying radii). We also present two sets of anthropogenic variables, human population density (within varying radii) and distance to large population center, which can serve as indicators of local human impacts. We have paired global, summarized layers available for download with an online data querying platform that allows users to extract data for specific point locations with finer control of summary statistics. In creating these global layers and online platform, we hope to make the data accessible to a wide array of end-users with the goal of advancing marine ecosystem studies. © 2017 by the Ecological Society of America.

Nutrient supply and mercury dynamics in marine ecosystems: A conceptual model

PubMed Central

Chen, Celia Y.; Hammerschmidt, Chad R.; Mason, Robert P.; Gilmour, Cynthia C.; Sunderland, Elsie M.; Greenfield, Ben K.; Buckman, Kate L.; Lamborg, Carl H.

2013-01-01

There is increasing interest and concern over the impacts of mercury (Hg) inputs to marine ecosystems. One of the challenges in assessing these effects is that the cycling and trophic transfer of Hg are strongly linked to other contaminants and disturbances. In addition to Hg, a major problem facing coastal waters is the impacts of elevated nutrient, particularly nitrogen (N), inputs. Increases in nutrient loading alter coastal ecosystems in ways that should change the transport, transformations and fate of Hg, including increases in fixation of organic carbon and deposition to sediments, decreases in the redox status of sediments and changes in fish habitat. In this paper we present a conceptual model which suggests that increases in loading of reactive N to marine ecosystems might alter Hg dynamics, decreasing bioavailabilty and trophic transfer. This conceptual model is most applicable to coastal waters, but may also be relevant to the pelagic ocean. We present information from case studies that both support and challenge this conceptual model, including marine observations across a nutrient gradient; results of a nutrient-trophic transfer Hg model for pelagic and coastal ecosystems; observations of Hg species, and nutrients from coastal sediments in the northeastern U.S.; and an analysis of fish Hg concentrations in estuaries under different nutrient loadings. These case studies suggest that changes in nutrient loading can impact Hg dynamics in coastal and open ocean ecosystems. Unfortunately none of the case studies is comprehensive; each only addresses a portion of the conceptual model and has limitations. Nevertheless, our conceptual model has important management implications. Many estuaries near developed areas are impaired due to elevated nutrient inputs. Widespread efforts are underway to control N loading and restore coastal ecosystem function. An unintended consequence of nutrient control measures could be to exacerbate problems associated with Hg contamination. Additional focused research and monitoring are needed to critically examine the link between nutrient supply and Hg contamination of marine waters. PMID:22749872

Ecosystem model of the entire Beaufort Sea marine ecosystem: a tool for assessing food-web structure and ecosystem changes from 1970 to 2014

NASA Astrophysics Data System (ADS)

Suprenand, P. M.; Hoover, C.

2016-02-01

The Beaufort Sea coastal-marine ecosystem is approximately a 476,000 km2 area in the Arctic Ocean, which extends from -112.5 to -158° longitude to 67.5 to 75° latitude. Within this Arctic Ocean area the United States (Alaskan) indigenous communities of Barrow, Kaktovik, and Nuiqsut, and the Canadian (Northwest Territories) indigenous communities of Aklavik, Inuvik, Tuktoyaktuk, Paulatuk, Ulukhaktok, and Sachs Harbour, subsist by harvesting marine mammals, fish, and invertebrates from the Beaufort Sea to provide the majority of their community foods annually. The ecosystem in which the indigenous communities harvest is considered a polar habitat that includes many specialized species, such as polar bears that rely on sea-ice for foraging activities and denning, or ice algae that are attached to the cryosphere. However, the polar habitat has been experiencing a diminishing sea-ice extent, age, and seasonal duration, with concomitant increases in sea surface temperatures (SSTs), since the 1970s. Changes in sea-ice and SST have consequences to the Beaufort Sea coastal-marine ecosystem, which includes animal habitat losses, alterations to trophodynamics, and impacts to subsistence community harvesting. The present study was aimed at capturing trophodynamic changes in the Beaufort Sea coastal-marine ecosystem from 1970 to 2014 using a fitted spatial-temporal model (Ecopath with Ecosim and Ecospace) that utilizes forcing and mediation functions to describe animal/trophodynamic relationships with sea-ice and sea surface temperature, as well as individual community harvesting efforts. Model outputs reveals similar trends in animals population changes (e.g., increasing bowhead whale stock), changes in apex predator diets (e.g., polar bears eating less ringed seal), and changes in animal distributions (e.g., polar bears remaining closer to land over time). The Beaufort Sea model is a dynamic tool for Arctic Ocean natural resource management in the years to come.

Nutrient supply and mercury dynamics in marine ecosystems: a conceptual model.

PubMed

Driscoll, Charles T; Chen, Celia Y; Hammerschmidt, Chad R; Mason, Robert P; Gilmour, Cynthia C; Sunderland, Elsie M; Greenfield, Ben K; Buckman, Kate L; Lamborg, Carl H

2012-11-01

There is increasing interest and concern over the impacts of mercury (Hg) inputs to marine ecosystems. One of the challenges in assessing these effects is that the cycling and trophic transfer of Hg are strongly linked to other contaminants and disturbances. In addition to Hg, a major problem facing coastal waters is the impacts of elevated nutrient, particularly nitrogen (N), inputs. Increases in nutrient loading alter coastal ecosystems in ways that should change the transport, transformations and fate of Hg, including increases in fixation of organic carbon and deposition to sediments, decreases in the redox status of sediments and changes in fish habitat. In this paper we present a conceptual model which suggests that increases in loading of reactive N to marine ecosystems might alter Hg dynamics, decreasing bioavailabilty and trophic transfer. This conceptual model is most applicable to coastal waters, but may also be relevant to the pelagic ocean. We present information from case studies that both support and challenge this conceptual model, including marine observations across a nutrient gradient; results of a nutrient-trophic transfer Hg model for pelagic and coastal ecosystems; observations of Hg species, and nutrients from coastal sediments in the northeastern U.S.; and an analysis of fish Hg concentrations in estuaries under different nutrient loadings. These case studies suggest that changes in nutrient loading can impact Hg dynamics in coastal and open ocean ecosystems. Unfortunately none of the case studies is comprehensive; each only addresses a portion of the conceptual model and has limitations. Nevertheless, our conceptual model has important management implications. Many estuaries near developed areas are impaired due to elevated nutrient inputs. Widespread efforts are underway to control N loading and restore coastal ecosystem function. An unintended consequence of nutrient control measures could be to exacerbate problems associated with Hg contamination. Additional focused research and monitoring are needed to critically examine the link between nutrient supply and Hg contamination of marine waters. Copyright © 2012 Elsevier Inc. All rights reserved.

Predicting the spatial and temporal distributions of marine fish species utilizing earth system data in a MaxEnt model framework

NASA Astrophysics Data System (ADS)

Wang, L.; Kerr, L. A.; Bridger, E.

2016-02-01

Changes in species distributions have been widely associated with climate change. Understanding how ocean temperatures influence species distributions is critical for elucidating the role of climate in ecosystem change as well as for forecasting how species may be distributed in the future. As such, species distribution modeling (SDM) is increasingly useful in marine ecosystems research, as it can enable estimation of the likelihood of encountering marine fish in space or time as a function of a set of environmental and ecosystem conditions. Many traditional SDM approaches are applied to species data collected through standardized methods that include both presence and absence records, but are incapable of using presence-only data, such as those collected from fisheries or through citizen science programs. Maximum entropy (MaxEnt) models provide promising tools as they can predict species distributions from incomplete information (presence-only data). We developed a MaxEnt framework to relate the occurrence records of several marine fish species (e.g. Atlantic herring, Atlantic mackerel, and butterfish) to environmental conditions. Environmental variables derived from remote sensing, such as monthly average sea surface temperature (SST), are matched with fish species data, and model results indicate the relative occurrence rate of the species as a function of the environmental variables. The results can be used to provide hindcasts of where species might have been in the past in relation to historical environmental conditions, nowcasts in relation to current conditions, and forecasts of future species distributions. In this presentation, we will assess the relative influence of several environmental factors on marine fish species distributions, and evaluate the effects of data coverage on these presence-only models. We will also discuss how the information from species distribution forecasts can support climate adaptation planning in marine fisheries.

Resilience of the Eastern Chukchi Sea Food Web to Mortality Based Perturbations and Identification of Ecologically Important Species

NASA Astrophysics Data System (ADS)

Whitehouse, G. A.; Aydin, K.

2016-02-01

Evidence of climate impacts on Arctic marine ecosystems is accumulating and Arctic marine ecosystems face additional pressures that may accompany increasing human activities due to improved access following reductions in sea ice cover. Thus, there is growing demand for information on how Arctic ecosystems may respond to potential disturbance. We explore the response of the eastern Chukchi Sea food web to mortality based perturbations using the dynamic food web modeling framework, Ecopath with Ecosim. We generated thousands of ecosystems by drawing random sets of model parameters from informative prior distributions and only retained those ecosystems that resulted in plausible, numerically stable configurations (no extinctions or population growth without limit). To perturb the systems, we increased mortality rates for selected functional groups then ran the retained models forward 50 years to examine how the biomass of other functional groups responded, and evaluated the resilience of the food web as the time for all functional groups to return to within 10 percent of their starting biomass. Ecologically important species were identified as those species (or functional groups of species) for whom changes in mortality had the greatest effect on the remainder of the food web. We also report on how a selection of ecosystem scale properties were affected by selected perturbations, including mean biomass longevity, the distribution of biomass across trophic levels, and a selection of dimensionless biomass ratios. These perturbations simulate a range of potential impacts that mortality events may have on the food web of the eastern Chukchi Sea, and indicate the directional response of other species and functional groups to these simulated events. This information will be of value to decision makers and resource managers developing guidelines for commercial and industrial development in the eastern Chukchi Sea.

Keystone taxa as drivers of microbiome structure and functioning.

PubMed

Banerjee, Samiran; Schlaeppi, Klaus; van der Heijden, Marcel G A

2018-05-22

Microorganisms have a pivotal role in the functioning of ecosystems. Recent studies have shown that microbial communities harbour keystone taxa, which drive community composition and function irrespective of their abundance. In this Opinion article, we propose a definition of keystone taxa in microbial ecology and summarize over 200 microbial keystone taxa that have been identified in soil, plant and marine ecosystems, as well as in the human microbiome. We explore the importance of keystone taxa and keystone guilds for microbiome structure and functioning and discuss the factors that determine their distribution and activities.

Hierarchical Synthesis of Coastal Ecosystem Health Indicators at Karimunjawa National Marine Park

NASA Astrophysics Data System (ADS)

Danu Prasetya, Johan; Ambariyanto; Supriharyono; Purwanti, Frida

2018-02-01

The coastal ecosystem of Karimunjawa National Marine Park (KNMP) is facing various pressures, including from human activity. Monitoring the health condition of coastal ecosystems periodically is needed as an evaluation of the ecosystem condition. Systematic and consistent indicators are needed in monitoring of coastal ecosystem health. This paper presents hierarchical synthesis of coastal ecosystem health indicators using Analytic Hierarchy Process (AHP) method. Hierarchical synthesis is obtained from process of weighting by paired comparison based on expert judgments. The variables of coastal ecosystem health indicators in this synthesis consist of 3 level of variable, i.e. main variable, sub-variable and operational variable. As a result of assessment, coastal ecosystem health indicators consist of 3 main variables, i.e. State of Ecosystem, Pressure and Management. Main variables State of Ecosystem and Management obtain the same value i.e. 0.400, while Pressure value was 0.200. Each main variable consist of several sub-variable, i.e. coral reef, reef fish, mangrove and seagrass for State of Ecosystem; fisheries and marine tourism activity for Pressure; planning and regulation, institutional and also infrastructure and financing for Management. The highest value of sub-variable of main variable State of Ecosystem, Pressure and Management were coral reef (0.186); marine tourism pressure (0.133) and institutional (0.171), respectively. The highest value of operational variable of main variable State of Ecosystem, Pressure and Management were percent of coral cover (0.058), marine tourism pressure (0.133) and presence of zonation plan, regulation also socialization of monitoring program (0.53), respectively. Potential pressure from marine tourism activity is the variable that most affect the health of the ecosystem. The results of this research suggest that there is a need to develop stronger conservation strategies to facing with pressures from marine tourism activities.

Night-time lighting alters the composition of marine epifaunal communities

PubMed Central

Davies, Thomas W.; Coleman, Matthew; Griffith, Katherine M.; Jenkins, Stuart R.

2015-01-01

Marine benthic communities face multiple anthropogenic pressures that compromise the future of some of the most biodiverse and functionally important ecosystems in the world. Yet one of the pressures these ecosystems face, night-time lighting, remains unstudied. Light is an important cue in guiding the settlement of invertebrate larvae, and altering natural regimes of nocturnal illumination could modify patterns of recruitment among sessile epifauna. We present the first evidence of night-time lighting changing the composition of temperate epifaunal marine invertebrate communities. Illuminating settlement surfaces with white light-emitting diode lighting at night, to levels experienced by these communities locally, both inhibited and encouraged the colonization of 39% of the taxa analysed, including three sessile and two mobile species. Our results indicate that ecological light pollution from coastal development, shipping and offshore infrastructure could be changing the composition of marine epifaunal communities. PMID:25926694

Role of environmental factors and microorganisms in determining the fate of polycyclic aromatic hydrocarbons in the marine environment

PubMed Central

Duran, Robert; Cravo-Laureau, Cristiana

2016-01-01

Polycyclic aromatic hydrocarbons (PAHs) are widespread in marine ecosystems and originate from natural sources and anthropogenic activities. PAHs enter the marine environment in two main ways, corresponding to chronic pollution or acute pollution by oil spills. The global PAH fluxes in marine environments are controlled by the microbial degradation and the biological pump, which plays a role in particle settling and in sequestration through bioaccumulation. Due to their low water solubility and hydrophobic nature, PAHs tightly adhere to sediments leading to accumulation in coastal and deep sediments. Microbial assemblages play an important role in determining the fate of PAHs in water and sediments, supporting the functioning of biogeochemical cycles and the microbial loop. This review summarises the knowledge recently acquired in terms of both chronic and acute PAH pollution. The importance of the microbial ecology in PAH-polluted marine ecosystems is highlighted as well as the importance of gaining further in-depth knowledge of the environmental services provided by microorganisms. PMID:28201512

Upgrading Marine Ecosystem Restoration Using Ecological-Social Concepts.

PubMed

Abelson, Avigdor; Halpern, Benjamin S; Reed, Daniel C; Orth, Robert J; Kendrick, Gary A; Beck, Michael W; Belmaker, Jonathan; Krause, Gesche; Edgar, Graham J; Airoldi, Laura; Brokovich, Eran; France, Robert; Shashar, Nadav; de Blaeij, Arianne; Stambler, Noga; Salameh, Pierre; Shechter, Mordechai; Nelson, Peter A

2016-02-01

Conservation and environmental management are principal countermeasures to the degradation of marine ecosystems and their services. However, in many cases, current practices are insufficient to reverse ecosystem declines. We suggest that restoration ecology , the science underlying the concepts and tools needed to restore ecosystems, must be recognized as an integral element for marine conservation and environmental management. Marine restoration ecology is a young scientific discipline, often with gaps between its application and the supporting science. Bridging these gaps is essential to using restoration as an effective management tool and reversing the decline of marine ecosystems and their services. Ecological restoration should address objectives that include improved ecosystem services, and it therefore should encompass social-ecological elements rather than focusing solely on ecological parameters. We recommend using existing management frameworks to identify clear restoration targets, to apply quantitative tools for assessment, and to make the re-establishment of ecosystem services a criterion for success.

Upgrading Marine Ecosystem Restoration Using Ecological‐Social Concepts

PubMed Central

Abelson, Avigdor; Halpern, Benjamin S.; Reed, Daniel C.; Orth, Robert J.; Kendrick, Gary A.; Beck, Michael W.; Belmaker, Jonathan; Krause, Gesche; Edgar, Graham J.; Airoldi, Laura; Brokovich, Eran; France, Robert; Shashar, Nadav; de Blaeij, Arianne; Stambler, Noga; Salameh, Pierre; Shechter, Mordechai; Nelson, Peter A.

2015-01-01

Conservation and environmental management are principal countermeasures to the degradation of marine ecosystems and their services. However, in many cases, current practices are insufficient to reverse ecosystem declines. We suggest that restoration ecology, the science underlying the concepts and tools needed to restore ecosystems, must be recognized as an integral element for marine conservation and environmental management. Marine restoration ecology is a young scientific discipline, often with gaps between its application and the supporting science. Bridging these gaps is essential to using restoration as an effective management tool and reversing the decline of marine ecosystems and their services. Ecological restoration should address objectives that include improved ecosystem services, and it therefore should encompass social–ecological elements rather than focusing solely on ecological parameters. We recommend using existing management frameworks to identify clear restoration targets, to apply quantitative tools for assessment, and to make the re-establishment of ecosystem services a criterion for success. PMID:26977115

Identifying Thresholds for Ecosystem-Based Management

PubMed Central

Samhouri, Jameal F.; Levin, Phillip S.; Ainsworth, Cameron H.

2010-01-01

Background One of the greatest obstacles to moving ecosystem-based management (EBM) from concept to practice is the lack of a systematic approach to defining ecosystem-level decision criteria, or reference points that trigger management action. Methodology/Principal Findings To assist resource managers and policymakers in developing EBM decision criteria, we introduce a quantitative, transferable method for identifying utility thresholds. A utility threshold is the level of human-induced pressure (e.g., pollution) at which small changes produce substantial improvements toward the EBM goal of protecting an ecosystem's structural (e.g., diversity) and functional (e.g., resilience) attributes. The analytical approach is based on the detection of nonlinearities in relationships between ecosystem attributes and pressures. We illustrate the method with a hypothetical case study of (1) fishing and (2) nearshore habitat pressure using an empirically-validated marine ecosystem model for British Columbia, Canada, and derive numerical threshold values in terms of the density of two empirically-tractable indicator groups, sablefish and jellyfish. We also describe how to incorporate uncertainty into the estimation of utility thresholds and highlight their value in the context of understanding EBM trade-offs. Conclusions/Significance For any policy scenario, an understanding of utility thresholds provides insight into the amount and type of management intervention required to make significant progress toward improved ecosystem structure and function. The approach outlined in this paper can be applied in the context of single or multiple human-induced pressures, to any marine, freshwater, or terrestrial ecosystem, and should facilitate more effective management. PMID:20126647

Near-future carbon dioxide levels alter fish behaviour by interfering with neurotransmitter function

NASA Astrophysics Data System (ADS)

Nilsson, Göran E.; Dixson, Danielle L.; Domenici, Paolo; McCormick, Mark I.; Sørensen, Christina; Watson, Sue-Ann; Munday, Philip L.

2012-03-01

Predicted future CO2 levels have been found to alter sensory responses and behaviour of marine fishes. Changes include increased boldness and activity, loss of behavioural lateralization, altered auditory preferences and impaired olfactory function. Impaired olfactory function makes larval fish attracted to odours they normally avoid, including ones from predators and unfavourable habitats. These behavioural alterations have significant effects on mortality that may have far-reaching implications for population replenishment, community structure and ecosystem function. However, the underlying mechanism linking high CO2 to these diverse responses has been unknown. Here we show that abnormal olfactory preferences and loss of behavioural lateralization exhibited by two species of larval coral reef fish exposed to high CO2 can be rapidly and effectively reversed by treatment with an antagonist of the GABA-A receptor. GABA-A is a major neurotransmitter receptor in the vertebrate brain. Thus, our results indicate that high CO2 interferes with neurotransmitter function, a hitherto unrecognized threat to marine populations and ecosystems. Given the ubiquity and conserved function of GABA-A receptors, we predict that rising CO2 levels could cause sensory and behavioural impairment in a wide range of marine species, especially those that tightly control their acid-base balance through regulatory changes in HCO3- and Cl- levels.

Impacts of fishing low-trophic level species on marine ecosystems.

PubMed

Smith, Anthony D M; Brown, Christopher J; Bulman, Catherine M; Fulton, Elizabeth A; Johnson, Penny; Kaplan, Isaac C; Lozano-Montes, Hector; Mackinson, Steven; Marzloff, Martin; Shannon, Lynne J; Shin, Yunne-Jai; Tam, Jorge

2011-08-26

Low-trophic level species account for more than 30% of global fisheries production and contribute substantially to global food security. We used a range of ecosystem models to explore the effects of fishing low-trophic level species on marine ecosystems, including marine mammals and seabirds, and on other commercially important species. In five well-studied ecosystems, we found that fishing these species at conventional maximum sustainable yield (MSY) levels can have large impacts on other parts of the ecosystem, particularly when they constitute a high proportion of the biomass in the ecosystem or are highly connected in the food web. Halving exploitation rates would result in much lower impacts on marine ecosystems while still achieving 80% of MSY.

Crab regulation of cross-ecosystem resource transfer by marine foraging fire ants.

PubMed

Garcia, Erica A; Bertness, Mark D; Alberti, Juan; Silliman, Brian R

2011-08-01

Permeability of boundaries in biological systems is regulated by biotic and/or abiotic factors. Despite this knowledge, the role of biotic factors in regulating resource transfer across ecosystem boundaries has received little study. Additionally, little is known about how cross-ecosystem resource transfer affects source populations. We used experiments, observations and stable isotopes, to evaluate: (1) the proportion of intertidal-foraging black fire ant (Solenopsis richteri) diet derived from marine sources, (2) how black fire ant cross-ecosystem resource transfer is altered by the dominant bioengineer in the intertidal, a burrowing crab (Neohelice granulata), (3) the top-down impact of these terrestrial ants on a marine resource, and (4) the effect of marine resources on recipient black fire ants. We found that more than 85% of the black fire ant diet is derived from marine sources, the number of intertidal foraging ants doubles in the absence of crab burrows, and that ants cause a 50% reduction in intertidal polychaetes. Also, ant mound density is three times greater adjacent to marine systems. This study reveals that cross-ecosystem foraging terrestrial ants can clearly have strong impacts on marine resources. Furthermore, ecosystem engineers that modify and occupy habitat in these ecosystem boundaries can strongly regulate the degree of cross-ecosystem resource transfer and resultant top down impacts.

Functional consequences of realistic biodiversity changes in a marine ecosystem

PubMed Central

Bracken, Matthew E. S.; Friberg, Sara E.; Gonzalez-Dorantes, Cirse A.; Williams, Susan L.

2008-01-01

Declines in biodiversity have prompted concern over the consequences of species loss for the goods and services provided by natural ecosystems. However, relatively few studies have evaluated the functional consequences of realistic, nonrandom changes in biodiversity. Instead, most designs have used randomly selected assemblages from a local species pool to construct diversity gradients. It is therefore difficult, based on current evidence, to predict the functional consequences of realistic declines in biodiversity. In this study, we used tide pool microcosms to demonstrate that the effects of real-world changes in biodiversity may be very different from those of random diversity changes. Specifically, we measured the relationship between the diversity of a seaweed assemblage and its ability to use nitrogen, a key limiting nutrient in nearshore marine systems. We quantified nitrogen uptake using both experimental and model seaweed assemblages and found that natural increases in diversity resulted in enhanced rates of nitrogen use, whereas random diversity changes had no effect on nitrogen uptake. Our results suggest that understanding the real-world consequences of declining biodiversity will require addressing changes in species performance along natural diversity gradients and understanding the relationships between species' susceptibility to loss and their contributions to ecosystem functioning. PMID:18195375

Climate change alters the structure of arctic marine food webs due to poleward shifts of boreal generalists.

PubMed

Kortsch, Susanne; Primicerio, Raul; Fossheim, Maria; Dolgov, Andrey V; Aschan, Michaela

2015-09-07

Climate-driven poleward shifts, leading to changes in species composition and relative abundances, have been recently documented in the Arctic. Among the fastest moving species are boreal generalist fish which are expected to affect arctic marine food web structure and ecosystem functioning substantially. Here, we address structural changes at the food web level induced by poleward shifts via topological network analysis of highly resolved boreal and arctic food webs of the Barents Sea. We detected considerable differences in structural properties and link configuration between the boreal and the arctic food webs, the latter being more modular and less connected. We found that a main characteristic of the boreal fish moving poleward into the arctic region of the Barents Sea is high generalism, a property that increases connectance and reduces modularity in the arctic marine food web. Our results reveal that habitats form natural boundaries for food web modules, and that generalists play an important functional role in coupling pelagic and benthic modules. We posit that these habitat couplers have the potential to promote the transfer of energy and matter between habitats, but also the spread of pertubations, thereby changing arctic marine food web structure considerably with implications for ecosystem dynamics and functioning. © 2015 The Authors.

Climate change alters the structure of arctic marine food webs due to poleward shifts of boreal generalists

PubMed Central

Kortsch, Susanne; Primicerio, Raul; Fossheim, Maria; Dolgov, Andrey V.; Aschan, Michaela

2015-01-01

Climate-driven poleward shifts, leading to changes in species composition and relative abundances, have been recently documented in the Arctic. Among the fastest moving species are boreal generalist fish which are expected to affect arctic marine food web structure and ecosystem functioning substantially. Here, we address structural changes at the food web level induced by poleward shifts via topological network analysis of highly resolved boreal and arctic food webs of the Barents Sea. We detected considerable differences in structural properties and link configuration between the boreal and the arctic food webs, the latter being more modular and less connected. We found that a main characteristic of the boreal fish moving poleward into the arctic region of the Barents Sea is high generalism, a property that increases connectance and reduces modularity in the arctic marine food web. Our results reveal that habitats form natural boundaries for food web modules, and that generalists play an important functional role in coupling pelagic and benthic modules. We posit that these habitat couplers have the potential to promote the transfer of energy and matter between habitats, but also the spread of pertubations, thereby changing arctic marine food web structure considerably with implications for ecosystem dynamics and functioning. PMID:26336179

VECTORS of change in the marine environment: Ecosystem and economic impacts and management implications

NASA Astrophysics Data System (ADS)

Austen, M. C.; Crowe, T. P.; Elliott, M.; Paterson, D. M.; Peck, M. A.; Piraino, S.

2018-02-01

Human use of the European marine environment is increasing and diversifying. This is creating new mechanisms for human induced-changes in marine life which need to be understood and quantified as well as the impact of these changes on ecosystems, their structures (e.g. biodiversity) and functioning (e.g. productivity), and the social and economic consequences that arise. The current and emerging pressures are multiple and interacting, arising, for example, from transport, platforms for renewable and non-renewable energy, exploitation of living and non-living resources, agricultural and industrial discharges, together with wider environmental changes (including climate change). Anticipating the future consequences of these pressures and vectors of change for marine life and of adaptation and mitigation measures (such as the introduction of new technologies and structures, new ballast water practices, ocean and offshore wind energy devices and new fishing strategies) is a prerequisite to the development and implementation of strategies, policies and regulations to manage the marine environment, such as the IMO Convention on ballast water management and the EU Maritime Policy and Marine Strategy Framework Directive.

Visualizing Ecosystem Energy Flow in Complex Food Web Networks: A Comparison of Three Alaskan Large Marine Ecosystems

NASA Astrophysics Data System (ADS)

Kearney, K.; Aydin, K.

2016-02-01

Oceanic food webs are often depicted as network graphs, with the major organisms or functional groups displayed as nodes and the fluxes of between them as the edges. However, the large number of nodes and edges and high connectance of many management-oriented food webs coupled with graph layout algorithms poorly-suited to certain desired characteristics of food web visualizations often lead to hopelessly tangled diagrams that convey little information other than, "It's complex." Here, I combine several new graph visualization techniques- including a new node layout alorithm based on a trophic similarity (quantification of shared predator and prey) and trophic level, divided edge bundling for edge routing, and intelligent automated placement of labels- to create a much clearer visualization of the important fluxes through a food web. The technique will be used to highlight the differences in energy flow within three Alaskan Large Marine Ecosystems (the Bering Sea, Gulf of Alaska, and Aleutian Islands) that include very similar functional groups but unique energy pathways.

Marine benthic ecological functioning over decreasing taxonomic richness

NASA Astrophysics Data System (ADS)

Törnroos, Anna; Bonsdorff, Erik; Bremner, Julie; Blomqvist, Mats; Josefson, Alf B.; Garcia, Clement; Warzocha, Jan

2015-04-01

Alterations to ecosystem function due to reductions in species richness are predicted to increase as humans continue to affect the marine environment, especially in coastal areas, which serve as the interface between land and sea. The potential functional consequences due to reductions in species diversity have attracted considerable attention recently but little is known about the consequence of such loss in natural communities. We examined how the potential for function is affected by natural reductions in taxon richness using empirical (non-simulated) coastal marine benthic macrofaunal data from the Skagerrak-Baltic Sea region (N. Europe), where taxon richness decreases 25-fold, from 151 to 6 taxa. To estimate functional changes we defined multiple traits (10 traits and 51 categories) on which trait category richness, functional diversity (FD) and number of taxa per trait category were calculated. Our results show that decrease in taxon richness leads to an overall reduction in function but functional richness remains comparatively high even at the lowest level of taxon richness. Although the taxonomic reduction was sharp, up to 96% of total taxon richness, we identified both potential thresholds in functioning and subtler changes where function was maintained along the gradient. The functional changes were not only caused by reductions in taxa per trait category, some categories were maintained or even increased. Primarily, the reduction in species richness altered trait categories related to feeding, living and movement and thus potentially could have an effect on various ecosystem processes. This highlights the importance of recognising ecosystem multifunctionality, especially at low taxonomic richness. We also found that in this system rare species (singletons) did not stand for the functional complexities and changes. Our findings were consistent with theoretical and experimental predictions and suggest that a large proportion of the information about alterations of function is found in measures such as functional diversity and number of taxa per trait category.

Identity effects dominate the impacts of multiple species extinctions on the functioning of complex food webs.

PubMed

Harvey, Eric; Séguin, Annie; Nozais, Christian; Archambault, Philippe; Gravel, Dominique

2013-01-01

Understanding the impacts of species extinctions on the functioning of food webs is a challenging task because of the complexity of ecological interactions. We report the impacts of experimental species extinctions on the functioning of two food webs of freshwater and marine systems. We used a linear model to partition the variance among the multiple components of the diversity effect (linear group richness, nonlinear group richness, and identity). The identity of each functional group was the best explaining variable of ecosystem functioning for both systems. We assessed the contribution of each functional group in multifunctional space and found that, although the effect of functional group varied across ecosystem functions, some functional groups shared common effects on functions. This study is the first experimental demonstration that functional identity dominates the effects of extinctions on ecosystem functioning, suggesting that generalizations are possible despite the inherent complexity of interactions.

Structure, functioning, and cumulative stressors of Mediterranean deep-sea ecosystems

NASA Astrophysics Data System (ADS)

Tecchio, Samuele; Coll, Marta; Sardà, Francisco

2015-06-01

Environmental stressors, such as climate fluctuations, and anthropogenic stressors, such as fishing, are of major concern for the management of deep-sea ecosystems. Deep-water habitats are limited by primary productivity and are mainly dependent on the vertical input of organic matter from the surface. Global change over the latest decades is imparting variations in primary productivity levels across oceans, and thus it has an impact on the amount of organic matter landing on the deep seafloor. In addition, anthropogenic impacts are now reaching the deep ocean. The Mediterranean Sea, the largest enclosed basin on the planet, is not an exception. However, ecosystem-level studies of response to varying food input and anthropogenic stressors on deep-sea ecosystems are still scant. We present here a comparative ecological network analysis of three food webs of the deep Mediterranean Sea, with contrasting trophic structure. After modelling the flows of these food webs with the Ecopath with Ecosim approach, we compared indicators of network structure and functioning. We then developed temporal dynamic simulations varying the organic matter input to evaluate its potential effect. Results show that, following the west-to-east gradient in the Mediterranean Sea of marine snow input, organic matter recycling increases, net production decreases to negative values and trophic organisation is overall reduced. The levels of food-web activity followed the gradient of organic matter availability at the seafloor, confirming that deep-water ecosystems directly depend on marine snow and are therefore influenced by variations of energy input, such as climate-driven changes. In addition, simulations of varying marine snow arrival at the seafloor, combined with the hypothesis of a possible fishery expansion on the lower continental slope in the western basin, evidence that the trawling fishery may pose an impact which could be an order of magnitude stronger than a climate-driven reduction of marine snow.

Patterns and Variation in Benthic Biodiversity in a Large Marine Ecosystem.

PubMed

Piacenza, Susan E; Barner, Allison K; Benkwitt, Cassandra E; Boersma, Kate S; Cerny-Chipman, Elizabeth B; Ingeman, Kurt E; Kindinger, Tye L; Lee, Jonathan D; Lindsley, Amy J; Reimer, Jessica N; Rowe, Jennifer C; Shen, Chenchen; Thompson, Kevin A; Thurman, Lindsey L; Heppell, Selina S

2015-01-01

While there is a persistent inverse relationship between latitude and species diversity across many taxa and ecosystems, deviations from this norm offer an opportunity to understand the conditions that contribute to large-scale diversity patterns. Marine systems, in particular, provide such an opportunity, as marine diversity does not always follow a strict latitudinal gradient, perhaps because several hypothesized drivers of the latitudinal diversity gradient are uncorrelated in marine systems. We used a large scale public monitoring dataset collected over an eight year period to examine benthic marine faunal biodiversity patterns for the continental shelf (55-183 m depth) and slope habitats (184-1280 m depth) off the US West Coast (47°20'N-32°40'N). We specifically asked whether marine biodiversity followed a strict latitudinal gradient, and if these latitudinal patterns varied across depth, in different benthic substrates, and over ecological time scales. Further, we subdivided our study area into three smaller regions to test whether coast-wide patterns of biodiversity held at regional scales, where local oceanographic processes tend to influence community structure and function. Overall, we found complex patterns of biodiversity on both the coast-wide and regional scales that differed by taxonomic group. Importantly, marine biodiversity was not always highest at low latitudes. We found that latitude, depth, substrate, and year were all important descriptors of fish and invertebrate diversity. Invertebrate richness and taxonomic diversity were highest at high latitudes and in deeper waters. Fish richness also increased with latitude, but exhibited a hump-shaped relationship with depth, increasing with depth up to the continental shelf break, ~200 m depth, and then decreasing in deeper waters. We found relationships between fish taxonomic and functional diversity and latitude, depth, substrate, and time at the regional scale, but not at the coast-wide scale, suggesting that coast-wide patterns can obscure important correlates at smaller scales. Our study provides insight into complex diversity patterns of the deep water soft substrate benthic ecosystems off the US West Coast.

Marine Phytophthora species can hamper conservation and restoration of vegetated coastal ecosystems

PubMed Central

Man in ‘t Veld, Willem A.; Meffert, Johan P.; Bouma, Tjeerd J.; van Rijswick, Patricia C. J.; Heusinkveld, Jannes H. T.; Orth, Robert J.; van Katwijk, Marieke M.; van der Heide, Tjisse

2016-01-01

Phytophthora species are potent pathogens that can devastate terrestrial plants, causing billions of dollars of damage yearly to agricultural crops and harming fragile ecosystems worldwide. Yet, virtually nothing is known about the distribution and pathogenicity of their marine relatives. This is surprising, as marine plants form vital habitats in coastal zones worldwide (i.e. mangrove forests, salt marshes, seagrass beds), and disease may be an important bottleneck for the conservation and restoration of these rapidly declining ecosystems. We are the first to report on widespread infection of Phytophthora and Halophytophthora species on a common seagrass species, Zostera marina (eelgrass), across the northern Atlantic and Mediterranean. In addition, we tested the effects of Halophytophthora sp. Zostera and Phytophthora gemini on Z. marina seed germination in a full-factorial laboratory experiment under various environmental conditions. Results suggest that Phytophthora species are widespread as we found these oomycetes in eelgrass beds in six countries across the North Atlantic and Mediterranean. Infection by Halophytophthora sp. Zostera, P. gemini, or both, strongly affected sexual reproduction by reducing seed germination sixfold. Our findings have important implications for seagrass ecology, because these putative pathogens probably negatively affect ecosystem functioning, as well as current restoration and conservation efforts. PMID:27559058

Oil platforms off California are among the most productive marine fish habitats globally

PubMed Central

Claisse, Jeremy T.; Pondella, Daniel J.; Love, Milton; Zahn, Laurel A.; Williams, Chelsea M.; Williams, Jonathan P.; Bull, Ann S.

2014-01-01

Secondary (i.e., heterotrophic or animal) production is a main pathway of energy flow through an ecosystem as it makes energy available to consumers, including humans. Its estimation can play a valuable role in the examination of linkages between ecosystem functions and services. We found that oil and gas platforms off the coast of California have the highest secondary fish production per unit area of seafloor of any marine habitat that has been studied, about an order of magnitude higher than fish communities from other marine ecosystems. Most previous estimates have come from estuarine environments, generally regarded as one of the most productive ecosystems globally. High rates of fish production on these platforms ultimately result from high levels of recruitment and the subsequent growth of primarily rockfish (genus Sebastes) larvae and pelagic juveniles to the substantial amount of complex hardscape habitat created by the platform structure distributed throughout the water column. The platforms have a high ratio of structural surface area to seafloor surface area, resulting in large amounts of habitat for juvenile and adult demersal fishes over a relatively small footprint of seafloor. Understanding the biological implications of these structures will inform policy related to the decommissioning of existing (e.g., oil and gas platforms) and implementation of emerging (e.g., wind, marine hydrokinetic) energy technologies. PMID:25313050

Ecological Energetic Perspectives on Responses of Nitrogen-Transforming Chemolithoautotrophic Microbiota to Changes in the Marine Environment

PubMed Central

Dang, Hongyue; Chen, Chen-Tung A.

2017-01-01

Transformation and mobilization of bioessential elements in the biosphere, lithosphere, atmosphere, and hydrosphere constitute the Earth’s biogeochemical cycles, which are driven mainly by microorganisms through their energy and material metabolic processes. Without microbial energy harvesting from sources of light and inorganic chemical bonds for autotrophic fixation of inorganic carbon, there would not be sustainable ecosystems in the vast ocean. Although ecological energetics (eco-energetics) has been emphasized as a core aspect of ecosystem analyses and microorganisms largely control the flow of matter and energy in marine ecosystems, marine microbial communities are rarely studied from the eco-energetic perspective. The diverse bioenergetic pathways and eco-energetic strategies of the microorganisms are essentially the outcome of biosphere-geosphere interactions over evolutionary times. The biogeochemical cycles are intimately interconnected with energy fluxes across the biosphere and the capacity of the ocean to fix inorganic carbon is generally constrained by the availability of nutrients and energy. The understanding of how microbial eco-energetic processes influence the structure and function of marine ecosystems and how they interact with the changing environment is thus fundamental to a mechanistic and predictive understanding of the marine carbon and nitrogen cycles and the trends in global change. By using major groups of chemolithoautotrophic microorganisms that participate in the marine nitrogen cycle as examples, this article examines their eco-energetic strategies, contributions to carbon cycling, and putative responses to and impacts on the various global change processes associated with global warming, ocean acidification, eutrophication, deoxygenation, and pollution. We conclude that knowledge gaps remain despite decades of tremendous research efforts. The advent of new techniques may bring the dawn to scientific breakthroughs that necessitate the multidisciplinary combination of eco-energetic, biogeochemical and “omics” studies in this field. PMID:28769878

Deep time ocean hypoxia: The impact on Jurassic marine ecosystems

NASA Astrophysics Data System (ADS)

Caswell, B. A.; Frid, C. L. J.

2016-02-01

In order to understand how the environment will change over the next 100-1000 years and how this will impact the biosphere we need long-term data from a range of scenarios. This long-term perspective can be achieved by looking at periods of comparable environmental change in Earth history. Two past periods of ocean deoxygenation, 150 and 183 million years ago, are compared: (1) a period of global climate change, analogous to that occurring today, and (2) a period of regional hypoxia associated with changing circulation and nutrient supply. Palaeoecological changes in populations, communities, and seafloor functioning were investigated using data spanning millions of years at high resolution (100s-1000s years). Large shifts in biodiversity, body-size and the population-size of the dominant benthic taxa occurred in response to ocean anoxia. Ecological change spanned multiple trophic levels and suggest that changes in primary productivity impacted macrobenthos and their pelagic predators resulting in biogeographic range shifts. Quantitative analyses of changes in biological traits and core ecosystem functions show changes in nutrient regeneration, food web dynamics, and benthic-pelagic coupling. During ocean deoxygenation Jurassic ecosystems showed functional resilience and redundancy, but ultimately functioning collapsed. Quantification of the relationships between ecological change and various proxies for palaeoenvironmental change show that both hypoxia and primary productivity were important drivers. Environmental thresholds for local ecosystem change are identified. The patterns of Jurassic ecosystem change share many similarities with present-day hypoxic systems. Critically, the recovery from global anoxia was very slow and connectivity, with potential sources of new recruits, was an important contributor to ecosystem recovery. This emphasises the risks of relying on patterns of short-term and small-scale resilience when managing modern marine systems.

Context-Dependent Diversity-Effects of Seaweed Consumption on Coral Reefs in Kenya

PubMed Central

Humphries, Austin T.; McQuaid, Christopher D.; McClanahan, Tim R.

2015-01-01

Consumers and prey diversity, their interactions, and subsequent effects on ecosystem function are important for ecological processes but not well understood in high diversity ecosystems such as coral reefs. Consequently, we tested the potential for diversity-effects with a series of surveys and experiments evaluating the influence of browsing herbivores on macroalgae in Kenya’s fringing reef ecosystem. We surveyed sites and undertook experiments in reefs subject to three levels of human fishing influence: open access fished reefs, small and recently established community-managed marine reserves, and larger, older government-managed marine reserves. Older marine reserves had a greater overall diversity of herbivores and browsers but this was not clearly associated with reduced macroalgal diversity or abundance. Experiments studying succession on hard substrata also found no effects of consumer diversity. Instead, overall browser abundance of either sea urchins or fishes was correlated with declines in macroalgal cover. An exception was that the absence of a key fish browser genus, Naso, which was correlated with the persistence of Sargassum in a marine reserve. Algal selectivity assays showed that macroalgae were consumed at variable rates, a product of strong species-specific feeding and low overlap in the selectivity of browsing fishes. We conclude that the effects of browser and herbivore diversity are less than the influences of key species, whose impacts emerge in different contexts that are influenced by fisheries management. Consequently, identifying key herbivore species and managing to protect them may assist protecting reef functions. PMID:26673609

Macroalgal blooms alter community structure and primary productivity in marine ecosystems.

PubMed

Lyons, Devin A; Arvanitidis, Christos; Blight, Andrew J; Chatzinikolaou, Eva; Guy-Haim, Tamar; Kotta, Jonne; Orav-Kotta, Helen; Queirós, Ana M; Rilov, Gil; Somerfield, Paul J; Crowe, Tasman P

2014-09-01

Eutrophication, coupled with loss of herbivory due to habitat degradation and overharvesting, has increased the frequency and severity of macroalgal blooms worldwide. Macroalgal blooms interfere with human activities in coastal areas, and sometimes necessitate costly algal removal programmes. They also have many detrimental effects on marine and estuarine ecosystems, including induction of hypoxia, release of toxic hydrogen sulphide into the sediments and atmosphere, and the loss of ecologically and economically important species. However, macroalgal blooms can also increase habitat complexity, provide organisms with food and shelter, and reduce other problems associated with eutrophication. These contrasting effects make their overall ecological impacts unclear. We conducted a systematic review and meta-analysis to estimate the overall effects of macroalgal blooms on several key measures of ecosystem structure and functioning in marine ecosystems. We also evaluated some of the ecological and methodological factors that might explain the highly variable effects observed in different studies. Averaged across all studies, macroalgal blooms had negative effects on the abundance and species richness of marine organisms, but blooms by different algal taxa had different consequences, ranging from strong negative to strong positive effects. Blooms' effects on species richness also depended on the habitat where they occurred, with the strongest negative effects seen in sandy or muddy subtidal habitats and in the rocky intertidal. Invertebrate communities also appeared to be particularly sensitive to blooms, suffering reductions in their abundance, species richness, and diversity. The total net primary productivity, gross primary productivity, and respiration of benthic ecosystems were higher during macroalgal blooms, but blooms had negative effects on the productivity and respiration of other organisms. These results suggest that, in addition to their direct social and economic costs, macroalgal blooms have ecological effects that may alter their capacity to deliver important ecosystem services. © 2014 John Wiley & Sons Ltd.

Modeling the impact of watershed management policies on marine ecosystem services with application to Hood Canal, WA, USA

NASA Astrophysics Data System (ADS)

Sutherland, D. A.; Kim, C.; Marsik, M.; Spiridonov, G.; Toft, J.; Ruckelshaus, M.; Guerry, A.; Plummer, M.

2011-12-01

Humans obtain numerous benefits from marine ecosystems, including fish to eat; mitigation of storm damage; nutrient and water cycling and primary production; and cultural, aesthetic and recreational values. However, managing these benefits, or ecosystem services, in the marine world relies on an integrated approach that accounts for both marine and watershed activities. Here we present the results of a set of simple, physically-based, and spatially-explicit models that quantify the effects of terrestrial activities on marine ecosystem services. Specifically, we model the circulation and water quality of Hood Canal, WA, USA, a fjord system in Puget Sound where multiple human uses of the nearshore ecosystem (e.g., shellfish aquaculture, recreational Dungeness crab and shellfish harvest) can be compromised when water quality is poor (e.g., hypoxia, excessive non-point source pollution). Linked to the estuarine water quality model is a terrestrial hydrology model that simulates streamflow and nutrient loading, so land cover and climate changes in watersheds can be reflected in the marine environment. In addition, a shellfish aquaculture model is linked to the water quality model to test the sensitivity of the ecosystem service and its value to both terrestrial and marine activities. The modeling framework is general and will be publicly available, allowing easy comparisons of watershed impacts on marine ecosystem services across multiple scales and regions.

Embedding ecosystem services into the Marine Strategy Framework Directive: Illustrated by eutrophication in the North Sea

NASA Astrophysics Data System (ADS)

O'Higgins, T. G.; Gilbert, A. J.

2014-03-01

The introduction of the Marine Strategy Framework Directive (MSFD) with its focus on an Ecosystem Approach places an emphasis on the human dimensions of environmental problems. Human activities may be the source of marine degradation, but may also be adversely affected should degradation compromise the provision of ecosystem services. The MSFD marks a shift away from management aiming to restore past, undegraded states toward management for Good Environmental Status (GEnS) based on delivery of marine goods and services. An example relating ecosystem services to criteria for Good Environmental Status is presented for eutrophication, a long recognised problem in many parts of Europe's seas and specifically targeted by descriptors for GEnS. Taking the North Sea as a case study the relationships between the eutrophication criteria of the MSFD and final and intermediate marine ecosystem services are examined. Ecosystem services are valued, where possible in monetary terms, in order to illustrate how eutrophication affects human welfare (economic externalities) through its multiple effects on ecosystem services.

Response of marine bacterioplankton pH homeostasis gene expression to elevated CO2

NASA Astrophysics Data System (ADS)

Bunse, Carina; Lundin, Daniel; Karlsson, Christofer M. G.; Akram, Neelam; Vila-Costa, Maria; Palovaara, Joakim; Svensson, Lovisa; Holmfeldt, Karin; González, José M.; Calvo, Eva; Pelejero, Carles; Marrasé, Cèlia; Dopson, Mark; Gasol, Josep M.; Pinhassi, Jarone

2016-05-01

Human-induced ocean acidification impacts marine life. Marine bacteria are major drivers of biogeochemical nutrient cycles and energy fluxes; hence, understanding their performance under projected climate change scenarios is crucial for assessing ecosystem functioning. Whereas genetic and physiological responses of phytoplankton to ocean acidification are being disentangled, corresponding functional responses of bacterioplankton to pH reduction from elevated CO2 are essentially unknown. Here we show, from metatranscriptome analyses of a phytoplankton bloom mesocosm experiment, that marine bacteria responded to lowered pH by enhancing the expression of genes encoding proton pumps, such as respiration complexes, proteorhodopsin and membrane transporters. Moreover, taxonomic transcript analysis showed that distinct bacterial groups expressed different pH homeostasis genes in response to elevated CO2. These responses were substantial for numerous pH homeostasis genes under low-chlorophyll conditions (chlorophyll a <2.5 μg l-1) however, the changes in gene expression under high-chlorophyll conditions (chlorophyll a >20 μg l-1) were low. Given that proton expulsion through pH homeostasis mechanisms is energetically costly, these findings suggest that bacterioplankton adaptation to ocean acidification could have long-term effects on the economy of ocean ecosystems.

The Sea Around Us Project: documenting and communicating global fisheries impacts on marine ecosystems.

PubMed

Pauly, Daniel

2007-06-01

The Sea Around Us Project, initiated by the Pew Charitable Trusts in Philadelphia, PA, and located at the Fisheries Centre, University of British Columbia, Vancouver, Canada, started in mid 1999. Its goal was (and still is) to investigate the impact of fisheries on marine ecosystems and to propose policies to mitigate these impacts. Although conceived as a global activity, the project first emphasized the data-rich North Atlantic as a test bed for developing its approaches, which rely on mapping of catch data and indicators of ecosystem health derived from the analysis of long catch time series data. Initial achievements included mapping the decline, throughout the North Atlantic basin, of high-trophic level fishes from 1900 to the present and the presentation of compelling evidence of change in the functioning of the North Atlantic ecosystems, summarized in a 2003 book. The Central and South Atlantic were the next basins to be tackled, with emphasis on the distant-water fleet off West Africa, culminating in a major conference in Dakar, Senegal, in 2002. The project then emphasized the North Pacific, Antarctica, and marine mammals and the multiplicity of tropical Indo-Pacific fisheries before it turned completely global, with all our major analyses and reports (e.g., on the interactions between marine mammals and fisheries, on fuel consumption by fleets, on the catches of small-scale fisheries, on subsidies to fisheries) being based on global studies. Broadly, the work of the project is aimed at a reappraisal of fisheries, from the benign activity that many interested people still perceive them to be, to a realization that they have become the driver for massive loss of biodiversity in the ocean. Moreover, the emphasis on global estimates (rather than local estimates of dubious generality) has allowed the project to contribute to various global initiatives (e.g., developing the Marine Trophic Index for the Convention on Biological Diversity, quantifying marine ecosystem services for the Millennium Ecosystem Assessment), that is, activities that we expect to increase and for which we invite collaboration from academia and environmental nongovernmental organizations.

A protocol for the intercomparison of marine fishery and ecosystem models: Fish-MIP v1.0

NASA Astrophysics Data System (ADS)

Tittensor, Derek P.; Eddy, Tyler D.; Lotze, Heike K.; Galbraith, Eric D.; Cheung, William; Barange, Manuel; Blanchard, Julia L.; Bopp, Laurent; Bryndum-Buchholz, Andrea; Büchner, Matthias; Bulman, Catherine; Carozza, David A.; Christensen, Villy; Coll, Marta; Dunne, John P.; Fernandes, Jose A.; Fulton, Elizabeth A.; Hobday, Alistair J.; Huber, Veronika; Jennings, Simon; Jones, Miranda; Lehodey, Patrick; Link, Jason S.; Mackinson, Steve; Maury, Olivier; Niiranen, Susa; Oliveros-Ramos, Ricardo; Roy, Tilla; Schewe, Jacob; Shin, Yunne-Jai; Silva, Tiago; Stock, Charles A.; Steenbeek, Jeroen; Underwood, Philip J.; Volkholz, Jan; Watson, James R.; Walker, Nicola D.

2018-04-01

Model intercomparison studies in the climate and Earth sciences communities have been crucial to building credibility and coherence for future projections. They have quantified variability among models, spurred model development, contrasted within- and among-model uncertainty, assessed model fits to historical data, and provided ensemble projections of future change under specified scenarios. Given the speed and magnitude of anthropogenic change in the marine environment and the consequent effects on food security, biodiversity, marine industries, and society, the time is ripe for similar comparisons among models of fisheries and marine ecosystems. Here, we describe the Fisheries and Marine Ecosystem Model Intercomparison Project protocol version 1.0 (Fish-MIP v1.0), part of the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP), which is a cross-sectoral network of climate impact modellers. Given the complexity of the marine ecosystem, this class of models has substantial heterogeneity of purpose, scope, theoretical underpinning, processes considered, parameterizations, resolution (grain size), and spatial extent. This heterogeneity reflects the lack of a unified understanding of the marine ecosystem and implies that the assemblage of all models is more likely to include a greater number of relevant processes than any single model. The current Fish-MIP protocol is designed to allow these heterogeneous models to be forced with common Earth System Model (ESM) Coupled Model Intercomparison Project Phase 5 (CMIP5) outputs under prescribed scenarios for historic (from the 1950s) and future (to 2100) time periods; it will be adapted to CMIP phase 6 (CMIP6) in future iterations. It also describes a standardized set of outputs for each participating Fish-MIP model to produce. This enables the broad characterization of differences between and uncertainties within models and projections when assessing climate and fisheries impacts on marine ecosystems and the services they provide. The systematic generation, collation, and comparison of results from Fish-MIP will inform an understanding of the range of plausible changes in marine ecosystems and improve our capacity to define and convey the strengths and weaknesses of model-based advice on future states of marine ecosystems and fisheries. Ultimately, Fish-MIP represents a step towards bringing together the marine ecosystem modelling community to produce consistent ensemble medium- and long-term projections of marine ecosystems.

Modelling impacts of offshore wind farms on trophic web: the Courseulles-sur-Mer case study

NASA Astrophysics Data System (ADS)

Raoux, Aurore; Pezy, Jean-Philippe; Dauvin, Jean-Claude; Tecchio, samuele; Degraer, Steven; Wilhelmsson, Dan; Niquil, Nathalie

2016-04-01

The French government is planning the construction of three offshore wind farms in Normandy. These offshore wind farms will integrate into an ecosystem already subject to a growing number of anthropogenic disturbances such as transportation, fishing, sediment deposit, and sediment extraction. The possible effects of this cumulative stressors on ecosystem functioning are still unknown, but they could impact their resilience, making them susceptible to changes from one stable state to another. Understanding the behaviour of these marine coastal complex systems is essential in order to anticipate potential state changes, and to implement conservation actions in a sustainable manner. Currently, there are no global and integrated studies on the effects of construction and exploitation of offshore wind farms. Moreover, approaches are generally focused on the conservation of some species or groups of species. Here, we develop a holistic and integrated view of ecosystem impacts through the use of trophic webs modelling tools. Trophic models describe the interaction between biological compartments at different trophic levels and are based on the quantification of flow of energy and matter in ecosystems. They allow the application of numerical methods for the characterization of emergent properties of the ecosystem, also called Ecological Network Analysis (ENA). These indices have been proposed as ecosystem health indicators as they have been demonstrated to be sensitive to different impacts on marine ecosystems. We present here in detail the strategy for analysing the potential environmental impacts of the construction of the Courseulles-sur-Mer offshore wind farm (Bay of Seine) such as the reef effect through the use of the Ecopath with Ecosim software. Similar Ecopath simulations will be made in the future on the Le Tréport offshore wind farm site. Results will contribute to a better knowledge of the impacts of the offshore wind farms on ecosystems. They also allow to define recommendations for environmental managers and industry in terms of monitoring the effects of Marine Renewable Energy, not only locally, but also on other sites, national and European levels. Finally, this approach could contribute to a better social acceptability of Marine Renewable Energy projects allowing a holistic vision of all pressures on ecosystems. Keywords: Marine Renewable Energies, trophic model Contact author: Aurore Raoux, UNICAEN, raoux.aurore@gmail.com

The Mar Piccolo of Taranto: an interesting marine ecosystem for the environmental problems studies.

PubMed

Cardellicchio, Nicola; Annicchiarico, Cristina; Di Leo, Antonella; Giandomenico, Santina; Spada, Lucia

2016-07-01

The National Project RITMARE (la Ricerca ITaliana per il MARE-Italian Research for the sea) started from 1 January 2012. It is one of the national research programs funded by the Italian Ministry of University and Research. RITMARE is coordinated by the National Research Council (CNR) and involves an integrated effort of most of the scientific community working on marine and maritime issues. Within the project, different marine study areas of strategic importance for the Mediterranean have been identified: Among these, the coastal area of Taranto (Ionian Sea, Southern Italy) was chosen for its different industry settlements and the relative impact on the marine environment. In particular, the research has been concentrated on the Mar Piccolo of Taranto, a complex marine ecosystem model important in terms of ecological, social, and economic activities for the presence also of extensive mussel farms. The site has been selected also because the Mar Piccolo area is a characteristic "on field" laboratory suitable to investigate release and diffusion mechanisms of contaminants, evaluate chemical-ecological risks towards the marine ecosystem and human health, and suggest and test potential remediation strategies for contaminated sediments. In this context, within the project RITMARE, a task force of researchers has contributed to elaboration a functioning conceptual model with a multidisciplinary approach useful to identify anthropogenic forcings, its impacts, and solutions of environmental remediation. This paper describes in brief some of the environmental issues related to the Mar Piccolo basin.

Looking for hotspots of marine metacommunity connectivity: a methodological framework

PubMed Central

Melià, Paco; Schiavina, Marcello; Rossetto, Marisa; Gatto, Marino; Fraschetti, Simonetta; Casagrandi, Renato

2016-01-01

Seascape connectivity critically affects the spatiotemporal dynamics of marine metacommunities. Understanding how connectivity patterns emerge from physically and biologically-mediated interactions is therefore crucial to conserve marine ecosystem functions and biodiversity. Here, we develop a set of biophysical models to explore connectivity in assemblages of species belonging to a typical Mediterranean community (Posidonia oceanica meadows) and characterized by different dispersing traits. We propose a novel methodological framework to synthesize species-specific results into a set of community connectivity metrics and show that spatiotemporal variation in magnitude and direction of the connections, as well as interspecific differences in dispersing traits, are key factors structuring community connectivity. We eventually demonstrate how these metrics can be used to characterize the functional role of each marine area in determining patterns of community connectivity at the basin level and to support marine conservation planning. PMID:27029563

Looking for hotspots of marine metacommunity connectivity: a methodological framework

NASA Astrophysics Data System (ADS)

Melià, Paco; Schiavina, Marcello; Rossetto, Marisa; Gatto, Marino; Fraschetti, Simonetta; Casagrandi, Renato

2016-03-01

Seascape connectivity critically affects the spatiotemporal dynamics of marine metacommunities. Understanding how connectivity patterns emerge from physically and biologically-mediated interactions is therefore crucial to conserve marine ecosystem functions and biodiversity. Here, we develop a set of biophysical models to explore connectivity in assemblages of species belonging to a typical Mediterranean community (Posidonia oceanica meadows) and characterized by different dispersing traits. We propose a novel methodological framework to synthesize species-specific results into a set of community connectivity metrics and show that spatiotemporal variation in magnitude and direction of the connections, as well as interspecific differences in dispersing traits, are key factors structuring community connectivity. We eventually demonstrate how these metrics can be used to characterize the functional role of each marine area in determining patterns of community connectivity at the basin level and to support marine conservation planning.

Development of innovative tools for understanding marine biodiversity and assessing good environmental status, within the European Marine Strategy Framework Directive

NASA Astrophysics Data System (ADS)

Borja, Angel; Uyarra, María C.

2014-05-01

Marine natural resources and ecosystem services constitute the natural capital that supports economies, societies and individual well-being. Good governance requires a quantification of the interactions and trade-offs among ecosystem services and understanding of how biodiversity underpins ecosystem functions and services across time, scales and sectors. Marine biodiversity is a key descriptor for the assessment within the Marine Strategy Framework Directive (MSFD), approved in 2008, which comprises a total of 11 descriptors. However, the relationships between pressures from human activities and climatic influences and their effects on marine biological diversity are still only partially understood. Hence, these relationships need to be better understood in order to fully achieve a good environmental status (GEnS), as required by the MSFD. This contribution is based upon the FP7 EU project DEVOTES (DEVelopment Of innovative Tools for understanding marine biodiversity and assessing good Environmental Status), which focus on developing innovative conceptual frameworks, methods and coherent, shared protocols to provide consistent datasets and knowledge at different scales, within four regional seas (Black Sea, Mediterranean, Atlantic and Baltic Sea). This project is developing innovative approaches to valuate biodiversity and ecosystem services and to develop public goods and sustainable economic activities from them. The research will benefit sea users and stakeholders, and will contribute to assess and monitor the environmental status of marine waters. The main objectives are: (i) to improve our understanding of the impact of human activities and variations associated to climate on marine biodiversity, (ii) to test indicators (referred in the Commission Decision on GEnS) and develop new ones for assessment at several ecological levels (species, habitat, ecosystems) and for the characterization and status classification of the marine waters, (iii) to develop, test and validate, on the basis of observations, innovative integrative modelling tools in order to further strengthen our understanding of ecosystem and biodiversity changes in space and time. The resultant models are being developed for implementation as operational tools for managers, decision takers and policy makers. The project is contributing (i) to enable the adaptive development of management (ecosystem-based management approach) strategies and management measures as a result of their implementation taking into account the role of industry and relevant stakeholders, (ii) to provide economic assessment of the consequences of management practices, (iii) to identify the barriers (socio-economic and legislative) that prevent the GES to be achieved (e.g. eutrophication), (iv) to provide a set of policy options for the relevant authorities. In addition the project should propose and demonstrate the utility of innovative monitoring systems capable of providing data on a range of parameters, efficiently and effectively, that may be used as indicators of good environmental status. This contribution presents a summary of most of these aspects.

A holistic view of marine regime shifts

PubMed Central

Conversi, Alessandra; Dakos, Vasilis; Gårdmark, Anna; Ling, Scott; Folke, Carl; Mumby, Peter J.; Greene, Charles; Edwards, Martin; Blenckner, Thorsten; Casini, Michele; Pershing, Andrew; Möllmann, Christian

2015-01-01

Understanding marine regime shifts is important not only for ecology but also for developing marine management that assures the provision of ecosystem services to humanity. While regime shift theory is well developed, there is still no common understanding on drivers, mechanisms and characteristic of abrupt changes in real marine ecosystems. Based on contributions to the present theme issue, we highlight some general issues that need to be overcome for developing a more comprehensive understanding of marine ecosystem regime shifts. We find a great divide between benthic reef and pelagic ocean systems in how regime shift theory is linked to observed abrupt changes. Furthermore, we suggest that the long-lasting discussion on the prevalence of top-down trophic or bottom-up physical drivers in inducing regime shifts may be overcome by taking into consideration the synergistic interactions of multiple stressors, and the special characteristics of different ecosystem types. We present a framework for the holistic investigation of marine regime shifts that considers multiple exogenous drivers that interact with endogenous mechanisms to cause abrupt, catastrophic change. This framework takes into account the time-delayed synergies of these stressors, which erode the resilience of the ecosystem and eventually enable the crossing of ecological thresholds. Finally, considering that increased pressures in the marine environment are predicted by the current climate change assessments, in order to avoid major losses of ecosystem services, we suggest that marine management approaches should incorporate knowledge on environmental thresholds and develop tools that consider regime shift dynamics and characteristics. This grand challenge can only be achieved through a holistic view of marine ecosystem dynamics as evidenced by this theme issue.

Marine Mammal Impacts in Exploited Ecosystems: Would Large Scale Culling Benefit Fisheries?

PubMed Central

Morissette, Lyne; Christensen, Villy; Pauly, Daniel

2012-01-01

Competition between marine mammals and fisheries for marine resources—whether real or perceived—has become a major issue for several countries and in international fora. We examined trophic interactions between marine mammals and fisheries based on a resource overlap index, using seven Ecopath models including marine mammal groups. On a global scale, most food consumed by marine mammals consisted of prey types that were not the main target of fisheries. For each ecosystem, the primary production required (PPR) to sustain marine mammals was less than half the PPR to sustain fisheries catches. We also developed an index representing the mean trophic level of marine mammal's consumption (TLQ) and compared it with the mean trophic level of fisheries' catches (TLC). Our results showed that overall TLQ was lower than TLC (2.88 versus 3.42). As fisheries increasingly exploit lower-trophic level species, the competition with marine mammals may become more important. We used mixed trophic impact analysis to evaluate indirect trophic effects of marine mammals, and in some cases found beneficial effects on some prey. Finally, we assessed the change in the trophic structure of an ecosystem after a simulated extirpation of marine mammal populations. We found that this lead to alterations in the structure of the ecosystems, and that there was no clear and direct relationship between marine mammals' predation and the potential catch by fisheries. Indeed, total biomass, with no marine mammals in the ecosystem, generally remained surprisingly similar, or even decreased for some species. PMID:22970153

Marine mammal impacts in exploited ecosystems: would large scale culling benefit fisheries?

PubMed

Morissette, Lyne; Christensen, Villy; Pauly, Daniel

2012-01-01

Competition between marine mammals and fisheries for marine resources-whether real or perceived-has become a major issue for several countries and in international fora. We examined trophic interactions between marine mammals and fisheries based on a resource overlap index, using seven Ecopath models including marine mammal groups. On a global scale, most food consumed by marine mammals consisted of prey types that were not the main target of fisheries. For each ecosystem, the primary production required (PPR) to sustain marine mammals was less than half the PPR to sustain fisheries catches. We also developed an index representing the mean trophic level of marine mammal's consumption (TL(Q)) and compared it with the mean trophic level of fisheries' catches (TL(C)). Our results showed that overall TL(Q) was lower than TL(C) (2.88 versus 3.42). As fisheries increasingly exploit lower-trophic level species, the competition with marine mammals may become more important. We used mixed trophic impact analysis to evaluate indirect trophic effects of marine mammals, and in some cases found beneficial effects on some prey. Finally, we assessed the change in the trophic structure of an ecosystem after a simulated extirpation of marine mammal populations. We found that this lead to alterations in the structure of the ecosystems, and that there was no clear and direct relationship between marine mammals' predation and the potential catch by fisheries. Indeed, total biomass, with no marine mammals in the ecosystem, generally remained surprisingly similar, or even decreased for some species.

[Effects of artificial reef construction to marine ecosystem services value: a case of Yang-Meikeng artificial reef region in Shenzhen].

PubMed

Qin, Chuan-xin; Chem, Pi-mao; Jia, Xiao-ping

2011-08-01

Based on the researches and statistic data of Yangmeikeng artificial reef region in Shenzhen in 2008 and by the method of ecosystem services value, this paper analyzed the effects of artificial reef construction in the region on the marine ecosystem services. After the artificial reef construction, the tourism service value in the region decreased from 87% to 42%, food supply service value increased from 7% to 27%, and the services value of raw material supply, climatic regulation, air quality regulation, water quality regulation, harmful organism and disease regulation, and knowledge expansion had a slight increase, as compared to the surrounding coastal areas. The total services value per unit area of Yangmeikeng artificial reef region in 2008 was 1714.7 x 10(4) yuan x km(-2), far higher than the mean services value of coastal marine ecosystem in the surrounding areas of Shenzhen and in the world. Artificial reef construction affected and altered the structure of regional marine ecosystem services value, and improved the regional ecosystem services value, being of significance for the rational exploitation and utilization of marine resources and the successful recovery of damaged marine eco-environment and fish resources. Utilizing the method of ecosystem services value to evaluate artificial reef construction region could better elucidate the benefits of artificial reef construction, effectively promote the development of our artificial reef construction, and improve the management of marine ecosystem.

Assessment of the impact of increased solar ultraviolet radiation upon marine ecosystems

NASA Technical Reports Server (NTRS)

Vandyke, H.

1977-01-01

Specifically, the study has addressed the following: (1) potential for irreversible damage to the productivity, structure and/or functioning of a model estuarine ecosystem by increased UV-B radiation or ecosystems highly stable or amenable to adaptive change, and (2) the sensitivity of key community components (the primary producers, consumers, and decomposers) to increased UV-B radiation. Three areas of study were examined during the past year: (1) a continuation of the study utilizing the two seminatural ecosystem chambers, (2) a pilot study utilizing three flow-through ecosystem tanks enclosed in a small, outdoor greenhouse, and (3) sensitivity studies of representative primary producers and consumers.

Marine biodiversity, ecosystem functioning, and carbon cycles.

PubMed

Beaugrand, Grégory; Edwards, Martin; Legendre, Louis

2010-06-01

Although recent studies suggest that climate change may substantially accelerate the rate of species loss in the biosphere, only a few studies have focused on the potential consequences of a spatial reorganization of biodiversity with global warming. Here, we show a pronounced latitudinal increase in phytoplanktonic and zooplanktonic biodiversity in the extratropical North Atlantic Ocean in recent decades. We also show that this rise in biodiversity paralleled a decrease in the mean size of zooplanktonic copepods and that the reorganization of the planktonic ecosystem toward dominance by smaller organisms may influence the networks in which carbon flows, with negative effects on the downward biological carbon pump and demersal Atlantic cod (Gadus morhua). Our study suggests that, contrary to the usual interpretation of increasing biodiversity being a positive emergent property promoting the stability/resilience of ecosystems, the parallel decrease in sizes of planktonic organisms could be viewed in the North Atlantic as reducing some of the services provided by marine ecosystems to humans.

The Economic Value of Coastal Ecosystems in California

EPA Science Inventory

The status of marine ecosystems affects the well being of human societies. These ecosystems include but are not limited to estuaries, lagoons, reefs, and systems further offshore such as deep ocean vents. The coastal regions that connect terrestrial and marine ecosystems are of p...

Global Patterns in Ecological Indicators of Marine Food Webs: A Modelling Approach

PubMed Central

Heymans, Johanna Jacomina; Coll, Marta; Libralato, Simone; Morissette, Lyne; Christensen, Villy

2014-01-01

Background Ecological attributes estimated from food web models have the potential to be indicators of good environmental status given their capabilities to describe redundancy, food web changes, and sensitivity to fishing. They can be used as a baseline to show how they might be modified in the future with human impacts such as climate change, acidification, eutrophication, or overfishing. Methodology In this study ecological network analysis indicators of 105 marine food web models were tested for variation with traits such as ecosystem type, latitude, ocean basin, depth, size, time period, and exploitation state, whilst also considering structural properties of the models such as number of linkages, number of living functional groups or total number of functional groups as covariate factors. Principal findings Eight indicators were robust to model construction: relative ascendency; relative overhead; redundancy; total systems throughput (TST); primary production/TST; consumption/TST; export/TST; and total biomass of the community. Large-scale differences were seen in the ecosystems of the Atlantic and Pacific Oceans, with the Western Atlantic being more complex with an increased ability to mitigate impacts, while the Eastern Atlantic showed lower internal complexity. In addition, the Eastern Pacific was less organised than the Eastern Atlantic although both of these systems had increased primary production as eastern boundary current systems. Differences by ecosystem type highlighted coral reefs as having the largest energy flow and total biomass per unit of surface, while lagoons, estuaries, and bays had lower transfer efficiencies and higher recycling. These differences prevailed over time, although some traits changed with fishing intensity. Keystone groups were mainly higher trophic level species with mostly top-down effects, while structural/dominant groups were mainly lower trophic level groups (benthic primary producers such as seagrass and macroalgae, and invertebrates). Keystone groups were prevalent in estuarine or small/shallow systems, and in systems with reduced fishing pressure. Changes to the abundance of key functional groups might have significant implications for the functioning of ecosystems and should be avoided through management. Conclusion/significance Our results provide additional understanding of patterns of structural and functional indicators in different ecosystems. Ecosystem traits such as type, size, depth, and location need to be accounted for when setting reference levels as these affect absolute values of ecological indicators. Therefore, establishing absolute reference values for ecosystem indicators may not be suitable to the ecosystem-based, precautionary approach. Reference levels for ecosystem indicators should be developed for individual ecosystems or ecosystems with the same typologies (similar location, ecosystem type, etc.) and not benchmarked against all other ecosystems. PMID:24763610

Global patterns in ecological indicators of marine food webs: a modelling approach.

PubMed

Heymans, Johanna Jacomina; Coll, Marta; Libralato, Simone; Morissette, Lyne; Christensen, Villy

2014-01-01

Ecological attributes estimated from food web models have the potential to be indicators of good environmental status given their capabilities to describe redundancy, food web changes, and sensitivity to fishing. They can be used as a baseline to show how they might be modified in the future with human impacts such as climate change, acidification, eutrophication, or overfishing. In this study ecological network analysis indicators of 105 marine food web models were tested for variation with traits such as ecosystem type, latitude, ocean basin, depth, size, time period, and exploitation state, whilst also considering structural properties of the models such as number of linkages, number of living functional groups or total number of functional groups as covariate factors. Eight indicators were robust to model construction: relative ascendency; relative overhead; redundancy; total systems throughput (TST); primary production/TST; consumption/TST; export/TST; and total biomass of the community. Large-scale differences were seen in the ecosystems of the Atlantic and Pacific Oceans, with the Western Atlantic being more complex with an increased ability to mitigate impacts, while the Eastern Atlantic showed lower internal complexity. In addition, the Eastern Pacific was less organised than the Eastern Atlantic although both of these systems had increased primary production as eastern boundary current systems. Differences by ecosystem type highlighted coral reefs as having the largest energy flow and total biomass per unit of surface, while lagoons, estuaries, and bays had lower transfer efficiencies and higher recycling. These differences prevailed over time, although some traits changed with fishing intensity. Keystone groups were mainly higher trophic level species with mostly top-down effects, while structural/dominant groups were mainly lower trophic level groups (benthic primary producers such as seagrass and macroalgae, and invertebrates). Keystone groups were prevalent in estuarine or small/shallow systems, and in systems with reduced fishing pressure. Changes to the abundance of key functional groups might have significant implications for the functioning of ecosystems and should be avoided through management. Our results provide additional understanding of patterns of structural and functional indicators in different ecosystems. Ecosystem traits such as type, size, depth, and location need to be accounted for when setting reference levels as these affect absolute values of ecological indicators. Therefore, establishing absolute reference values for ecosystem indicators may not be suitable to the ecosystem-based, precautionary approach. Reference levels for ecosystem indicators should be developed for individual ecosystems or ecosystems with the same typologies (similar location, ecosystem type, etc.) and not benchmarked against all other ecosystems.

Trophic amplification of climate warming

PubMed Central

Kirby, Richard R.; Beaugrand, Gregory

2009-01-01

Ecosystems can alternate suddenly between contrasting persistent states due to internal processes or external drivers. It is important to understand the mechanisms by which these shifts occur, especially in exploited ecosystems. There have been several abrupt marine ecosystem shifts attributed either to fishing, recent climate change or a combination of these two drivers. We show that temperature has been an important driver of the trophodynamics of the North Sea, a heavily fished marine ecosystem, for nearly 50 years and that a recent pronounced change in temperature established a new ecosystem dynamic regime through a series of internal mechanisms. Using an end-to-end ecosystem approach that included primary producers, primary, secondary and tertiary consumers, and detritivores, we found that temperature modified the relationships among species through nonlinearities in the ecosystem involving ecological thresholds and trophic amplifications. Trophic amplification provides an alternative mechanism to positive feedback to drive an ecosystem towards a new dynamic regime, which in this case favours jellyfish in the plankton and decapods and detritivores in the benthos. Although overfishing is often held responsible for marine ecosystem degeneration, temperature can clearly bring about similar effects. Our results are relevant to ecosystem-based fisheries management (EBFM), seen as the way forward to manage exploited marine ecosystems. PMID:19740882

Sustainable oceans and coasts: Lessons learnt from Eastern and Western Africa

NASA Astrophysics Data System (ADS)

Diop, S.; Scheren, P. A.

2016-12-01

Marine and coastal ecosystems in Africa provide valuable cultural (recreational, spiritual), provisioning (such as food, timber and firewood) and regulatory (such as flood protection and climate regulation) services that are not only at the core of coastal ecosystem functioning, but are also an important basis for the economic livelihoods of over 120 million inhabitants living along the continent's coastal zone. However, these valuable ecosystems are being subjected to a range of human pressures, including overfishing and destructive fishing practices, pollution, including excess nutrients (causing eutrophication), loss and degradation of habitats, physical shoreline changes and disturbance of the hydrological regimes of rivers and estuarine systems, aggravated further by the effects of climate change. The effects of these pressures, often acting in cumulative and synergistic manners, readily affect the overall stability of the coastal ecosystems, threatening their resilience over the short- and long-term. This chapter highlights the challenges faced by the coastal states of Eastern and Western Africa in managing their coastal and marine resources for the sustainable benefits of their populations. Current mechanisms for the governance and management of the coastal and marine environment at national to regional scales are reviewed, and their effectiveness appraised, and recommendations for improved management and scientific support are made.

Sensitivity of secondary production and export flux to choice of trophic transfer formulation in marine ecosystem models

NASA Astrophysics Data System (ADS)

Anderson, Thomas R.; Hessen, Dag O.; Mitra, Aditee; Mayor, Daniel J.; Yool, Andrew

2013-09-01

The performance of four contemporary formulations describing trophic transfer, which have strongly contrasting assumptions as regards the way that consumer growth is calculated as a function of food C:N ratio and in the fate of non-limiting substrates, was compared in two settings: a simple steady-state ecosystem model and a 3D biogeochemical general circulation model. Considerable variation was seen in predictions for primary production, transfer to higher trophic levels and export to the ocean interior. The physiological basis of the various assumptions underpinning the chosen formulations is open to question. Assumptions include Liebig-style limitation of growth, strict homeostasis in zooplankton biomass, and whether excess C and N are released by voiding in faecal pellets or via respiration/excretion post-absorption by the gut. Deciding upon the most appropriate means of formulating trophic transfer is not straightforward because, despite advances in ecological stoichiometry, the physiological mechanisms underlying these phenomena remain incompletely understood. Nevertheless, worrying inconsistencies are evident in the way in which fundamental transfer processes are justified and parameterised in the current generation of marine ecosystem models, manifested in the resulting simulations of ocean biogeochemistry. Our work highlights the need for modellers to revisit and appraise the equations and parameter values used to describe trophic transfer in marine ecosystem models.

Divergent ecosystem responses within a benthic marine community to ocean acidification.

PubMed

Kroeker, Kristy J; Micheli, Fiorenza; Gambi, Maria Cristina; Martz, Todd R

2011-08-30

Ocean acidification is predicted to impact all areas of the oceans and affect a diversity of marine organisms. However, the diversity of responses among species prevents clear predictions about the impact of acidification at the ecosystem level. Here, we used shallow water CO(2) vents in the Mediterranean Sea as a model system to examine emergent ecosystem responses to ocean acidification in rocky reef communities. We assessed in situ benthic invertebrate communities in three distinct pH zones (ambient, low, and extreme low), which differed in both the mean and variability of seawater pH along a continuous gradient. We found fewer taxa, reduced taxonomic evenness, and lower biomass in the extreme low pH zones. However, the number of individuals did not differ among pH zones, suggesting that there is density compensation through population blooms of small acidification-tolerant taxa. Furthermore, the trophic structure of the invertebrate community shifted to fewer trophic groups and dominance by generalists in extreme low pH, suggesting that there may be a simplification of food webs with ocean acidification. Despite high variation in individual species' responses, our findings indicate that ocean acidification decreases the diversity, biomass, and trophic complexity of benthic marine communities. These results suggest that a loss of biodiversity and ecosystem function is expected under extreme acidification scenarios.

Marine Phytophthora species can hamper conservation and restoration of vegetated coastal ecosystems.

PubMed

Govers, Laura L; Man In 't Veld, Willem A; Meffert, Johan P; Bouma, Tjeerd J; van Rijswick, Patricia C J; Heusinkveld, Jannes H T; Orth, Robert J; van Katwijk, Marieke M; van der Heide, Tjisse

2016-08-31

Phytophthora species are potent pathogens that can devastate terrestrial plants, causing billions of dollars of damage yearly to agricultural crops and harming fragile ecosystems worldwide. Yet, virtually nothing is known about the distribution and pathogenicity of their marine relatives. This is surprising, as marine plants form vital habitats in coastal zones worldwide (i.e. mangrove forests, salt marshes, seagrass beds), and disease may be an important bottleneck for the conservation and restoration of these rapidly declining ecosystems. We are the first to report on widespread infection of Phytophthora and Halophytophthora species on a common seagrass species, Zostera marina (eelgrass), across the northern Atlantic and Mediterranean. In addition, we tested the effects of Halophytophthora sp. Zostera and Phytophthora gemini on Z. marina seed germination in a full-factorial laboratory experiment under various environmental conditions. Results suggest that Phytophthora species are widespread as we found these oomycetes in eelgrass beds in six countries across the North Atlantic and Mediterranean. Infection by Halophytophthora sp. Zostera, P. gemini, or both, strongly affected sexual reproduction by reducing seed germination sixfold. Our findings have important implications for seagrass ecology, because these putative pathogens probably negatively affect ecosystem functioning, as well as current restoration and conservation efforts. © 2016 The Author(s).

Unravelling core microbial metabolisms in the hypersaline microbial mats of Shark Bay using high-throughput metagenomics

PubMed Central

Ruvindy, Rendy; White III, Richard Allen; Neilan, Brett Anthony; Burns, Brendan Paul

2016-01-01

Modern microbial mats are potential analogues of some of Earth's earliest ecosystems. Excellent examples can be found in Shark Bay, Australia, with mats of various morphologies. To further our understanding of the functional genetic potential of these complex microbial ecosystems, we conducted for the first time shotgun metagenomic analyses. We assembled metagenomic next-generation sequencing data to classify the taxonomic and metabolic potential across diverse morphologies of marine mats in Shark Bay. The microbial community across taxonomic classifications using protein-coding and small subunit rRNA genes directly extracted from the metagenomes suggests that three phyla Proteobacteria, Cyanobacteria and Bacteriodetes dominate all marine mats. However, the microbial community structure between Shark Bay and Highbourne Cay (Bahamas) marine systems appears to be distinct from each other. The metabolic potential (based on SEED subsystem classifications) of the Shark Bay and Highbourne Cay microbial communities were also distinct. Shark Bay metagenomes have a metabolic pathway profile consisting of both heterotrophic and photosynthetic pathways, whereas Highbourne Cay appears to be dominated almost exclusively by photosynthetic pathways. Alternative non-rubisco-based carbon metabolism including reductive TCA cycle and 3-hydroxypropionate/4-hydroxybutyrate pathways is highly represented in Shark Bay metagenomes while not represented in Highbourne Cay microbial mats or any other mat forming ecosystems investigated to date. Potentially novel aspects of nitrogen cycling were also observed, as well as putative heavy metal cycling (arsenic, mercury, copper and cadmium). Finally, archaea are highly represented in Shark Bay and may have critical roles in overall ecosystem function in these modern microbial mats. PMID:26023869

Cumulative Human Impacts on Mediterranean and Black Sea Marine Ecosystems: Assessing Current Pressures and Opportunities

PubMed Central

Micheli, Fiorenza; Halpern, Benjamin S.; Walbridge, Shaun; Ciriaco, Saul; Ferretti, Francesco; Fraschetti, Simonetta; Lewison, Rebecca; Nykjaer, Leo; Rosenberg, Andrew A.

2013-01-01

Management of marine ecosystems requires spatial information on current impacts. In several marine regions, including the Mediterranean and Black Sea, legal mandates and agreements to implement ecosystem-based management and spatial plans provide new opportunities to balance uses and protection of marine ecosystems. Analyses of the intensity and distribution of cumulative impacts of human activities directly connected to the ecological goals of these policy efforts are critically needed. Quantification and mapping of the cumulative impact of 22 drivers to 17 marine ecosystems reveals that 20% of the entire basin and 60–99% of the territorial waters of EU member states are heavily impacted, with high human impact occurring in all ecoregions and territorial waters. Less than 1% of these regions are relatively unaffected. This high impact results from multiple drivers, rather than one individual use or stressor, with climatic drivers (increasing temperature and UV, and acidification), demersal fishing, ship traffic, and, in coastal areas, pollution from land accounting for a majority of cumulative impacts. These results show that coordinated management of key areas and activities could significantly improve the condition of these marine ecosystems. PMID:24324585

Emergent Global Patterns of Ecosystem Structure and Function from a Mechanistic General Ecosystem Model

PubMed Central

Emmott, Stephen; Hutton, Jon; Lyutsarev, Vassily; Smith, Matthew J.; Scharlemann, Jörn P. W.; Purves, Drew W.

2014-01-01

Anthropogenic activities are causing widespread degradation of ecosystems worldwide, threatening the ecosystem services upon which all human life depends. Improved understanding of this degradation is urgently needed to improve avoidance and mitigation measures. One tool to assist these efforts is predictive models of ecosystem structure and function that are mechanistic: based on fundamental ecological principles. Here we present the first mechanistic General Ecosystem Model (GEM) of ecosystem structure and function that is both global and applies in all terrestrial and marine environments. Functional forms and parameter values were derived from the theoretical and empirical literature where possible. Simulations of the fate of all organisms with body masses between 10 µg and 150,000 kg (a range of 14 orders of magnitude) across the globe led to emergent properties at individual (e.g., growth rate), community (e.g., biomass turnover rates), ecosystem (e.g., trophic pyramids), and macroecological scales (e.g., global patterns of trophic structure) that are in general agreement with current data and theory. These properties emerged from our encoding of the biology of, and interactions among, individual organisms without any direct constraints on the properties themselves. Our results indicate that ecologists have gathered sufficient information to begin to build realistic, global, and mechanistic models of ecosystems, capable of predicting a diverse range of ecosystem properties and their response to human pressures. PMID:24756001

Emergent global patterns of ecosystem structure and function from a mechanistic general ecosystem model.

PubMed

Harfoot, Michael B J; Newbold, Tim; Tittensor, Derek P; Emmott, Stephen; Hutton, Jon; Lyutsarev, Vassily; Smith, Matthew J; Scharlemann, Jörn P W; Purves, Drew W

2014-04-01

Anthropogenic activities are causing widespread degradation of ecosystems worldwide, threatening the ecosystem services upon which all human life depends. Improved understanding of this degradation is urgently needed to improve avoidance and mitigation measures. One tool to assist these efforts is predictive models of ecosystem structure and function that are mechanistic: based on fundamental ecological principles. Here we present the first mechanistic General Ecosystem Model (GEM) of ecosystem structure and function that is both global and applies in all terrestrial and marine environments. Functional forms and parameter values were derived from the theoretical and empirical literature where possible. Simulations of the fate of all organisms with body masses between 10 µg and 150,000 kg (a range of 14 orders of magnitude) across the globe led to emergent properties at individual (e.g., growth rate), community (e.g., biomass turnover rates), ecosystem (e.g., trophic pyramids), and macroecological scales (e.g., global patterns of trophic structure) that are in general agreement with current data and theory. These properties emerged from our encoding of the biology of, and interactions among, individual organisms without any direct constraints on the properties themselves. Our results indicate that ecologists have gathered sufficient information to begin to build realistic, global, and mechanistic models of ecosystems, capable of predicting a diverse range of ecosystem properties and their response to human pressures.

Great Lakes rivermouth ecosystems: scientific synthesis and management implications

USGS Publications Warehouse

Larson, James H.; Trebitz, Anett S.; Steinman, Alan D.; Wiley, Michael J.; Carlson Mazur, Martha; Pebbles, Victoria; Braun, Heather A.; Seelbach, Paul W.

2013-01-01

At the interface of the Great Lakes and their tributary rivers lies the rivermouths, a class of aquatic ecosystem where lake and lotic processes mix and distinct features emerge. Many rivermouths are the focal point of both human interaction with the Great Lakes and human impacts to the lakes; many cities, ports, and beaches are located in rivermouth ecosystems, and these human pressures often degrade key ecological functions that rivermouths provide. Despite their ecological uniqueness and apparent economic importance, there has been relatively little research on these ecosystems as a class relative to studies on upstream rivers or the open-lake waters. Here we present a synthesis of current knowledge about ecosystem structure and function in Great Lakes rivermouths based on studies in both Laurentian rivermouths, coastal wetlands, and marine estuarine systems. A conceptual model is presented that establishes a common semantic framework for discussing the characteristic spatial features of rivermouths. This model then is used to conceptually link ecosystem structure and function to ecological services provided by rivermouths. This synthesis helps identify the critical gaps in understanding rivermouth ecology. Specifically, additional information is needed on how rivermouths collectively influence the Great Lakes ecosystem, how human alterations influence rivermouth functions, and how ecosystem services provided by rivermouths can be managed to benefit the surrounding socioeconomic networks.

Exploring the co-evolution of marine ecology and environment in silico

NASA Astrophysics Data System (ADS)

Ridgwell, A.

2015-12-01

Species do not live in isolation, but adapt and ultimately, evolve, in relationship with other species as well as with their chemical and physical environment. In the marine environment, this interaction is intimately two-way - the surface biogeochemical environment modulates the makeup of the pelagic ecosystem, yet at the same time, the ecosystem assemblage, by setting the strength of the biological pump and ultimately, in regulating the carbon and nutrient inventory of the ocean and atmospheric pCO2, influences the surface geochemical environment. Feedbacks, both negative and positive, must therefore exist between plankton ecology and global biogeochemical cycles. This has implications for understanding the geological record and particularly the response and recovery of marine ecosystems following major environmental perturbation, but also complicates making projections of future ocean changes. To address a coupled system such as this, new numerical tools are needed as traditional 'functional type' marine ecosystem models are generally incapable of accounting for short-term adaptation, let alone long-term evolution. What is needed is the combination of a plankton model able to simulate a highly diverse ecology plus 'genetic' mutation (changes in trait value(s)) and extinction, *and* an Earth system model capable of simulating long-term evolution of the climatology and geochemistry of the ocean. The Earth system model 'cGENIE' - http://mycgenie.seao2.org generally fills the second criteria, so for this presentation I will focus on the structure of the ecosystem model, the associated methodology, and numerical techniques for dealing with what will turn out to be an exceptionally large number of ocean tracers. If you are really lucky, there may even be some preliminary results :)

Placing biodiversity in ecosystem models without getting lost in translation

NASA Astrophysics Data System (ADS)

Queirós, Ana M.; Bruggeman, Jorn; Stephens, Nicholas; Artioli, Yuri; Butenschön, Momme; Blackford, Jeremy C.; Widdicombe, Stephen; Allen, J. Icarus; Somerfield, Paul J.

2015-04-01

A key challenge to progressing our understanding of biodiversity's role in the sustenance of ecosystem function is the extrapolation of the results of two decades of dedicated empirical research to regional, global and future landscapes. Ecosystem models provide a platform for this progression, potentially offering a holistic view of ecosystems where, guided by the mechanistic understanding of processes and their connection to the environment and biota, large-scale questions can be investigated. While the benefits of depicting biodiversity in such models are widely recognized, its application is limited by difficulties in the transfer of knowledge from small process oriented ecology into macro-scale modelling. Here, we build on previous work, breaking down key challenges of that knowledge transfer into a tangible framework, highlighting successful strategies that both modelling and ecology communities have developed to better interact with one another. We use a benthic and a pelagic case-study to illustrate how aspects of the links between biodiversity and ecosystem process have been depicted in marine ecosystem models (ERSEM and MIRO), from data, to conceptualisation and model development. We hope that this framework may help future interactions between biodiversity researchers and model developers by highlighting concrete solutions to common problems, and in this way contribute to the advance of the mechanistic understanding of the role of biodiversity in marine (and terrestrial) ecosystems.

Tool kit development to refine and visualize essential climate data and information for marine protected areas

NASA Astrophysics Data System (ADS)

Cecil, L.; Stachniewicz, J.; Shein, K. A.; Ansari, S.; Jarvis, C.

2013-05-01

Marine ecosystem responses to climate variability and change such as changing water temperature, water chemistry (e.g., pH, salinity), water level, or storminess may result in adverse impacts including mass mortality, loss of habitat, increased disease susceptibility, and trophic cascade feedbacks. Unfortunately, while marine ecosystem resource managers are aware of these threats, they often lack sufficient expertise with identifying, accessing and using the many large and complex climate data products that would inform ecosystem-scale climate impact assessments. NOAA's National Climatic Data Center (NCDC) has been working with the Gulf of the Farallones National Marine Sanctuary Ocean Climate Center to enhance and expand the functionality of NCDC's Weather and Climate Toolkit (WCT) to begin to address this limitation. The WCT is a freely available, Java-based user interface (http://www.ncdc.noaa.gov/oa/wct/) designed to access, analyze, and display a variety of NCDC's georeferenced climate data products (e.g., satellite data, radar, reanalysis datasets, in-situ observations). However, the WCT requires the user to have already identified a data set of interest and gained access to it. This can limit its utility by users who are not knowledgeable about which data sets are relevant to their needs and where those data sets can be found. The Integrated Marine Protected Area Climate Tools (IMPACT) prototype modification to the WCT addresses those requirements through an iterative process between climate scientists and resource managers. The WCT-IMPACT prototype couples a user query approach with a quasi-expert system that determines, retrieves, and loads the appropriate data products for visualization and analysis by the user. Relevant data products are identified based on the environmental variables in which ecosystem managers have indicated an importance to their ecosystems. To improve response time, the user, through the WCT-IMPACT interface, crops (or subsets) the larger gridded data products, such as NOAA's satellite Climate Data Records to the geographic boundaries of each included marine protected area (MPA). These clipped data sets are processed to produce MPA-specific analytics (e.g., files for averages, extremes, peaks over threshold, etc). Once a specific MPA has been selected, the associated data may be visualized, analyzed, and exported to other formats (e.g., netCDF, KML) from within the tool. The WCT-IMPACT tool kit will provide marine ecosystem managers with the capacity to answer such questions as what was the climate like during periods of optimal ecological health, or have climate conditions changed equally across an ecosystem's domain? The WCT-IMPACT extension is being developed specifically to address the needs of marine ecosystem managers to have access to relevant climate data and information for developing ecosystem-scale climate assessments, while retaining the ability for a WCT user to identify and access the full suite of georeferenced climate data provided by NCDC. In this tool kit development scheme, the need to coordinate with the resource managers is paramount and end user participation in an iterative process with the climate scientists is essential.

An original model of the northern Gulf of Mexico using Ecopath with Ecosim and its implications for the effects of fishing on ecosystem structure and maturity

NASA Astrophysics Data System (ADS)

Geers, T. M.; Pikitch, E. K.; Frisk, M. G.

2016-07-01

The Gulf of Mexico (GoM) is a valuable ecosystem both socially and economically, and fisheries contribute substantially to this value. Gulf menhaden, Brevoortia patronus, support the largest fishery in the Gulf (by weight) and provide forage for marine mammals, seabirds and commercially and recreationally important fish species. Understanding the complex interactions among multiple fisheries and myriad unfished species requires tools different from those used in traditional single-species management. One such tool, Ecopath with Ecosim (EwE) is increasingly being used to construct food web models of aquatic ecosystems and to evaluate fisheries management options within a broader, ecosystem context. Here, an EwE model was developed to examine the impact of Gulf fisheries on ecosystem structure and maturity. This model builds on previously published EwE models of the GoM, and is tailored to the range and habitat of Gulf menhaden. The model presented here consists of 47 functional groups, including 4 seabird groups, 1 marine mammal group, 3 elasmobranch groups, 26 bony fish groups, 9 invertebrate groups, 3 primary producer groups and 1 detritus group. A number of different management scenarios for Gulf fisheries were modeled and the results were evaluated in terms of impacts on ecosystem maturity and development. The results of the model simulations indicated that the northern Gulf of Mexico is in an immature state (sensuOdum, 1969). Management scenarios that increased fishing pressure over time consistently resulted in a decrease in the maturity indices. In particular, we found that Gulf menhaden, as a key forage fish in the ecosystem, plays a substantial role in the structure and functioning of the ecosystem.

Integrating parasitology and marine ecology: Seven challenges towards greater synergy

NASA Astrophysics Data System (ADS)

Poulin, Robert; Blasco-Costa, Isabel; Randhawa, Haseeb S.

2016-07-01

Despite their very different historical origins as scientific disciplines, parasitology and marine ecology have already combined successfully to make important contributions to our understanding of the functioning of natural ecosystems. For example, robust assessments of the contribution of parasites to ecosystem biomass and energetics, and of their impact on community-wide biodiversity and food web structure, have all been made for the first time in marine systems. Nevertheless, for the marriage between parasitology and marine ecology to remain fruitful, several challenges must first be overcome. We discuss seven such challenges on the road to a greater synergy between these disciplines: (1) Raising awareness of parasitism as an ecological force by increasing the proportion of articles about parasites and diseases in marine ecology journals; (2) Making greater use of theory and conceptual frameworks from marine ecology to guide parasitological research; (3) Speeding up or at least maintaining the current rate at which marine parasites are found and described; (4) Elucidating a greater proportion of life cycles in all major groups of marine parasites; (5) Increasing the number of host-parasite model systems on which our knowledge is based; (6) Extending parasitological research offshore and into ocean depths; and (7) Developing, as needed, new epidemiological theory and transmission models for the marine environment. None of these challenges is insurmountable, and addressing just a few of them should guarantee that parasitology and marine ecology will continue to join forces and make further substantial contributions.

Exploring local adaptation and the ocean acidification seascape - studies in the California Current Large Marine Ecosystem

NASA Astrophysics Data System (ADS)

Hofmann, G. E.; Evans, T. G.; Kelly, M. W.; Padilla-Gamiño, J. L.; Blanchette, C. A.; Washburn, L.; Chan, F.; McManus, M. A.; Menge, B. A.; Gaylord, B.; Hill, T. M.; Sanford, E.; LaVigne, M.; Rose, J. M.; Kapsenberg, L.; Dutton, J. M.

2013-07-01

The California Current Large Marine Ecosystem (CCLME), a temperate marine region dominated by episodic upwelling, is predicted to experience rapid environmental change in the future due to ocean acidification. Aragonite saturation state within the California Current System is predicted to decrease in the future, with near-permanent undersaturation conditions expected by the year 2050. Thus, the CCLME is a critical region to study due to the rapid rate of environmental change that resident organisms will experience and because of the economic and societal value of this coastal region. Recent efforts by a research consortium - the Ocean Margin Ecosystems Group for Acidification Studies (OMEGAS) - has begun to characterize a portion of the CCLME; both describing the mosaic of pH in coastal waters and examining the responses of key calcification-dependent benthic marine organisms to natural variation in pH and to changes in carbonate chemistry that are expected in the coming decades. In this review, we present the OMEGAS strategy of co-locating sensors and oceanographic observations with biological studies on benthic marine invertebrates, specifically measurements of functional traits such as calcification-related processes and genetic variation in populations that are locally adapted to conditions in a particular region of the coast. Highlighted in this contribution are (1) the OMEGAS sensor network that spans the west coast of the US from central Oregon to southern California, (2) initial findings of the carbonate chemistry amongst the OMEGAS study sites, (3) an overview of the biological data that describes the acclimatization and the adaptation capacity of key benthic marine invertebrates within the CCLME.

What kind of disturbances did March 11, 2011 Tohoku Earthquake and Tsunamis leave continental margin ecosystems? : Lessons from five years monitoring research

NASA Astrophysics Data System (ADS)

Kitazato, Hiroshi; Kijima, Akihiro; Kogure, Kazuhiro; Hara, Motoyuki; Nagata, Toshi; Fujikura, Kasunori; Sonoda, Akira

2016-04-01

On March 11, 2011, huge earthquake with M9.0 took place at Japan Trench area off Northeast Japan. Vigorous disturbances of marine environments and ecosystems have taken place at coastal areas where huge tsunamis swept sediments and organisms away from the coastal areas to deeper oceans. Distributional pattern of sediments and organisms in coves and bays have strongly changed after tsunamis. Marine ecosystems at Northeast Japan have totally disturbed and damaged. Scientists from Tohoku University, the University of Tokyo and JAMSTEC have started to monitor how much marine ecosystem disturbed and how it may recover. A research team, named Tohoku Ecosystem-Associated Marine Sciences, continually makes research on marine ecosystems as ten years monitoring project funded by MEXT, Japan since 2011. On 2016, it takes five years from the Earthquake and Tsunami occurred. What happens marine ecosystems at Tohoku area during these years. Water column ecosystems are rather easy to recover from disturbances. Seaweed communities have strongly damaged, but, they gradually recover. Sediment communities have not recovered yet as sediment distribution is different from before earthquake and tsunamis. Most difficulties are scars in human minds. We, scientists, try to share scientific activities and results with local peoples including fishermen and local governments for better understanding of both oceanic conditions and fishery resources. Disaster risk reduction should accelerate with resilience of community structure. But, mental resilience is the most effective way to recover human activities at the damaged areas.

Threats, Challenges, and Promise of Marine Microbes: A NOAA Perspective with Emphasis on Ecological Forecasting

NASA Astrophysics Data System (ADS)

Sandifer, P. A.

2012-12-01

Fully functioning ecosystems, as well as healthy humans, depend on robust and diverse communities of microbes. The diversity of microbes in the marine environment is estimated to be huge, dwarfing diversity of other life forms, and crucial for many ecosystem processes. Despite the ubiquity and extreme importance of microbial life in the sea - from the air-surface interface to the deepest abyss and sediments - we know relatively little about this biotic component that may compose a large proportion of the total biomass on the planet. As the nation's principal steward of marine living resources, NOAA is both responsible for and vitally interested in marine microbes, from a variety of perspectives. These include (1) health threats to humans and other organisms and how these may be affected by climate change and ecosystem alteration; (2) detoxification of organic pollutants such as hydrocarbons (e.g., in the Deep Water Horizon oil catastrophe); (3) production of valuable natural products including potential new pharmaceuticals; (4) roles in biogeochemical cycles (e.g., for carbon, nitrogen, phosphorus, iron, etc.) and how human activities may affect these roles; (5) development and deployment of new methods to detect and quantify certain marine microbes, and incorporation of these into ocean observing systems; (6) development of Earth System models that include much improved understanding of microbial functional diversity and microbially mediated biogeochemical processes; (7) dynamics of bacterial, phyto- and zooplankton blooms, including for harmful algae and bacteria; (8) effects of climate change factors (e.g., temperature, CO2 concentrations, ocean acidification, changes in habitats and species distribution, etc.) on marine microbes; and others. Many of these topics likely will be discussed by others in this session. This presentation will focus primarily on NOAA's activities in addressing health threats emanating from a variety of microbes in the marine environment and the agency's developing efforts to collect routine observational data on selected microbes and establish regular forecasts of such threats and their likely impacts. Such "ecological forecasts" are projected to become a regular part of NOAA's service portfolio and may be expanded beyond disease-causing microbes in the future.

Patterns and Variation in Benthic Biodiversity in a Large Marine Ecosystem

PubMed Central

Lee, Jonathan D.

2015-01-01

While there is a persistent inverse relationship between latitude and species diversity across many taxa and ecosystems, deviations from this norm offer an opportunity to understand the conditions that contribute to large-scale diversity patterns. Marine systems, in particular, provide such an opportunity, as marine diversity does not always follow a strict latitudinal gradient, perhaps because several hypothesized drivers of the latitudinal diversity gradient are uncorrelated in marine systems. We used a large scale public monitoring dataset collected over an eight year period to examine benthic marine faunal biodiversity patterns for the continental shelf (55–183 m depth) and slope habitats (184–1280 m depth) off the US West Coast (47°20′N—32°40′N). We specifically asked whether marine biodiversity followed a strict latitudinal gradient, and if these latitudinal patterns varied across depth, in different benthic substrates, and over ecological time scales. Further, we subdivided our study area into three smaller regions to test whether coast-wide patterns of biodiversity held at regional scales, where local oceanographic processes tend to influence community structure and function. Overall, we found complex patterns of biodiversity on both the coast-wide and regional scales that differed by taxonomic group. Importantly, marine biodiversity was not always highest at low latitudes. We found that latitude, depth, substrate, and year were all important descriptors of fish and invertebrate diversity. Invertebrate richness and taxonomic diversity were highest at high latitudes and in deeper waters. Fish richness also increased with latitude, but exhibited a hump-shaped relationship with depth, increasing with depth up to the continental shelf break, ~200 m depth, and then decreasing in deeper waters. We found relationships between fish taxonomic and functional diversity and latitude, depth, substrate, and time at the regional scale, but not at the coast-wide scale, suggesting that coast-wide patterns can obscure important correlates at smaller scales. Our study provides insight into complex diversity patterns of the deep water soft substrate benthic ecosystems off the US West Coast. PMID:26308521

Assessing ecological correlates of marine bird declines to inform marine conservation.

PubMed

Vilchis, L Ignacio; Johnson, Christine K; Evenson, Joseph R; Pearson, Scott F; Barry, Karen L; Davidson, Peter; Raphael, Martin G; Gaydos, Joseph K

2015-02-01

Identifying drivers of ecosystem change in large marine ecosystems is central for their effective management and conservation. This is a sizable challenge, particularly in ecosystems transcending international borders, where monitoring and conservation of long-range migratory species and their habitats are logistically and financially problematic. Here, using tools borrowed from epidemiology, we elucidated common drivers underlying species declines within a marine ecosystem, much in the way epidemiological analyses evaluate risk factors for negative health outcomes to better inform decisions. Thus, we identified ecological traits and dietary specializations associated with species declines in a community of marine predators that could be reflective of ecosystem change. To do so, we integrated count data from winter surveys collected in long-term marine bird monitoring programs conducted throughout the Salish Sea--a transboundary large marine ecosystem in North America's Pacific Northwest. We found that decadal declines in winter counts were most prevalent among pursuit divers such as alcids (Alcidae) and grebes (Podicipedidae) that have specialized diets based on forage fish, and that wide-ranging species without local breeding colonies were more prone to these declines. Although a combination of factors is most likely driving declines of diving forage fish specialists, we propose that changes in the availability of low-trophic prey may be forcing wintering range shifts of diving birds in the Salish Sea. Such a synthesis of long-term trends in a marine predator community not only provides unique insights into the types of species that are at risk of extirpation and why, but may also inform proactive conservation measures to counteract threats--information that is paramount for species-specific and ecosystem-wide conservation. © 2014 The Authors. Conservation Biology published by Wiley Periodicals, Inc., on behalf of the Society for Conservation Biology.

Parasites and marine invasions: Ecological and evolutionary perspectives

NASA Astrophysics Data System (ADS)

Goedknegt, M. Anouk; Feis, Marieke E.; Wegner, K. Mathias; Luttikhuizen, Pieternella C.; Buschbaum, Christian; Camphuysen, Kees (C. J.); van der Meer, Jaap; Thieltges, David W.

2016-07-01

Worldwide, marine and coastal ecosystems are heavily invaded by introduced species and the potential role of parasites in the success and impact of marine invasions has been increasingly recognized. In this review, we link recent theoretical developments in invasion ecology with empirical studies from marine ecosystems in order to provide a conceptual framework for studying the role of parasites and their hosts in marine invasions. Based on an extensive literature search, we identified six mechanisms in which invaders directly or indirectly affect parasite and host populations and communities: I) invaders can lose some or all of their parasites during the invasion process (parasite release or reduction), often causing a competitive advantage over native species; II) invaders can also act as a host for native parasites, which may indirectly amplify the parasite load of native hosts (parasite spillback); III) invaders can also be parasites themselves and be introduced without needing co-introduction of the host (introduction of free-living infective stages); IV) alternatively, parasites may be introduced together with their hosts (parasite co-introduction with host); V) consequently, these co-introduced parasites can sometimes also infect native hosts (parasite spillover); and VI) invasive species may be neither a host nor a parasite, but nevertheless affect native parasite host interactions by interfering with parasite transmission (transmission interference). We discuss the ecological and evolutionary implications of each of these mechanisms and generally note several substantial effects on natural communities and ecosystems via i) mass mortalities of native populations creating strong selection gradients, ii) indirect changes in species interactions within communities and iii) trophic cascading and knock-on effects in food webs that may affect ecosystem function and services. Our review demonstrates a wide range of ecological and evolutionary implications of marine invasions for parasite-host interactions and suggests that parasite-mediated impacts should be integrated in assessing the risks and consequences of biological invasions.

Assessing the main threats to marine ecosystem components of the Adriatic - Ionian Region for the implementation of Maritime Spatial Planning

NASA Astrophysics Data System (ADS)

Lipizer, Marina

2015-04-01

Marine and coastal ecosystems and the related benefits they provide for humans are threatened by increasing pressures and competing usages. To address these issues, in the last decade, several EU legislations have been formulated to guarantee and promote sustainable use of the sea (e.g. Common Fishery Policy, Marine Strategy Framework Directive, Maritime Spatial Planning). As a first step to implement cross-border Maritime Spatial Planning (MSP) in the Adriatic - Ionian Seas, a review of the main anthropogenic pressures due to maritime activities involving the Adriatic - Ionian Region (AIR) as well as of the most relevant environmental components has been carried out. The main objective of the analysis is to better identify the spatial distribution of human uses of the sea and of the key environmental components and the ecosystem services provided. The analysis of the existing conditions includes a description of the human activities per economic sector, considering type, location, dimension and magnitude of the activity in the AIR and the spatial extent of the main environmental and ecological values present in the AIR. The environmental status has been characterized according to the descriptors proposed by the Marine Strategy Framework Directive (MSFD Directive 2008/56/EC) and the most sensitive ecosystem components in the AIR have been pointed out. A qualitative analysis of the relationships between good environmental status descriptors sensu MSFD and ecosystem services in the AIR has been carried out to provide useful information for the implementation of MSP. Cross-border Maritime Spatial Planning is particularly needed in a semi-enclosed basin such as the Adriatic Sea, hosting very diverse human activities, ranging from fishery to tourism, sand extraction, commercial and passenger transport, oil and gas exploration and exploitation, which may partially overlap and severely threaten ecosystem functioning and the associated services.

Functional Redundancy Patterns Reveal Non-Random Assembly Rules in a Species-Rich Marine Assemblage

PubMed Central

Guillemot, Nicolas; Kulbicki, Michel; Chabanet, Pascale; Vigliola, Laurent

2011-01-01

The relationship between species and the functional diversity of assemblages is fundamental in ecology because it contains key information on functional redundancy, and functionally redundant ecosystems are thought to be more resilient, resistant and stable. However, this relationship is poorly understood and undocumented for species-rich coastal marine ecosystems. Here, we used underwater visual censuses to examine the patterns of functional redundancy for one of the most diverse vertebrate assemblages, the coral reef fishes of New Caledonia, South Pacific. First, we found that the relationship between functional and species diversity displayed a non-asymptotic power-shaped curve, implying that rare functions and species mainly occur in highly diverse assemblages. Second, we showed that the distribution of species amongst possible functions was significantly different from a random distribution up to a threshold of ∼90 species/transect. Redundancy patterns for each function further revealed that some functions displayed fast rates of increase in redundancy at low species diversity, whereas others were only becoming redundant past a certain threshold. This suggested non-random assembly rules and the existence of some primordial functions that would need to be fulfilled in priority so that coral reef fish assemblages can gain a basic ecological structure. Last, we found little effect of habitat on the shape of the functional-species diversity relationship and on the redundancy of functions, although habitat is known to largely determine assemblage characteristics such as species composition, biomass, and abundance. Our study shows that low functional redundancy is characteristic of this highly diverse fish assemblage, and, therefore, that even species-rich ecosystems such as coral reefs may be vulnerable to the removal of a few keystone species. PMID:22039543

Future direction in marine bacterial agarases for industrial applications.

PubMed

Jahromi, Saeid Tamadoni; Barzkar, Noora

2018-06-16

The marine ecosystem has been known to be a rich source of novel enzymes. Agarase is a key enzyme that can hydrolyze agar in the marine environment. Marine bacterial agarase has been isolated from various sources, such as sediments, coastal water, and deep sea and from the surface of crustaceans and seaweeds. This review presents an account of the agarase production of marine bacteria. General information about agar, agarase, isolation, and purification of marine bacterial agarases; the biochemical properties of native agarase from marine bacteria; the biochemical properties of recombinant marine bacterial agarases from engineered microorganisms; and the industrial future of marine bacterial agarases is analyzed. With recent biotechnological processes, researchers need novel functional enzymes like agarase from marine resources, such as marine bacteria, that can be used for diverse applications in the biotechnological industry. Marine bacterial agarases might be of significant interest to the industry because they are safe and are a natural source. This review highlights the potential of marine bacteria as important sources of agarase for application in various industries.

What did we learn from PEGASEAS forum "Science and Governance of the Channel Marine Ecosystem"?

PubMed

Evariste, Emmanuelle; Claquin, Pascal; Robin, Jean-Paul; Auber, Arnaud; McQuatters-Gollop, Abigail; Fletcher, Stephen; Glegg, Gillian; Dauvin, Jean-Claude

2015-04-15

As one of the busiest marine ecosystems in the world, the English Channel is subjected to strong pressures due to the human activities occurring within it. Effective governance is required to improve the combined management of different activities and so secure the benefits provided by the Channel ecosystem. In July 2014, a Cross-Channel Forum, entitled "Science and Governance of the Channel Marine Ecosystem", was held in Caen (France) as part of the INTERREG project "Promoting Effective Governance of the Channel Ecosystem" (PEGASEAS). Here we use outputs from the Forum as a framework for providing Channel-specific advice and recommendations on marine governance themes, including the identification of knowledge gaps, which may form the foundation of future projects for the next INTERREG project call (2015-2020). Copyright © 2015 Elsevier Ltd. All rights reserved.

Marine and giant viruses as indicators of a marine microbial community in a riverine system.

PubMed

Dann, Lisa M; Rosales, Stephanie; McKerral, Jody; Paterson, James S; Smith, Renee J; Jeffries, Thomas C; Oliver, Rod L; Mitchell, James G

2016-12-01

Viral communities are important for ecosystem function as they are involved in critical biogeochemical cycles and controlling host abundance. This study investigates riverine viral communities around a small rural town that influences local water inputs. Myoviridae, Siphoviridae, Phycodnaviridae, Mimiviridae, Herpesviridae, and Podoviridae were the most abundant families. Viral species upstream and downstream of the town were similar, with Synechoccocus phage, salinus, Prochlorococcus phage, Mimivirus A, and Human herpes 6A virus most abundant, contributing to 4.9-38.2% of average abundance within the metagenomic profiles, with Synechococcus and Prochlorococcus present in metagenomes as the expected hosts for the phage. Overall, the majority of abundant viral species were or were most similar to those of marine origin. At over 60 km to the river mouth, the presence of marine communities provides some support for the Baas-Becking hypothesis "everything is everywhere, but, the environment selects." We conclude marine microbial species may occur more frequently in freshwater systems than previously assumed, and hence may play important roles in some freshwater ecosystems within tens to a hundred kilometers from the sea. © 2016 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

Biodiversity enhances reef fish biomass and resistance to climate change.

PubMed

Duffy, J Emmett; Lefcheck, Jonathan S; Stuart-Smith, Rick D; Navarrete, Sergio A; Edgar, Graham J

2016-05-31

Fishes are the most diverse group of vertebrates, play key functional roles in aquatic ecosystems, and provide protein for a billion people, especially in the developing world. Those functions are compromised by mounting pressures on marine biodiversity and ecosystems. Because of its economic and food value, fish biomass production provides an unusually direct link from biodiversity to critical ecosystem services. We used the Reef Life Survey's global database of 4,556 standardized fish surveys to test the importance of biodiversity to fish production relative to 25 environmental drivers. Temperature, biodiversity, and human influence together explained 47% of the global variation in reef fish biomass among sites. Fish species richness and functional diversity were among the strongest predictors of fish biomass, particularly for the large-bodied species and carnivores preferred by fishers, and these biodiversity effects were robust to potentially confounding influences of sample abundance, scale, and environmental correlations. Warmer temperatures increased biomass directly, presumably by raising metabolism, and indirectly by increasing diversity, whereas temperature variability reduced biomass. Importantly, diversity and climate interact, with biomass of diverse communities less affected by rising and variable temperatures than species-poor communities. Biodiversity thus buffers global fish biomass from climate change, and conservation of marine biodiversity can stabilize fish production in a changing ocean.

Biodiversity enhances reef fish biomass and resistance to climate change

PubMed Central

Duffy, J. Emmett; Lefcheck, Jonathan S.; Navarrete, Sergio A.; Edgar, Graham J.

2016-01-01

Fishes are the most diverse group of vertebrates, play key functional roles in aquatic ecosystems, and provide protein for a billion people, especially in the developing world. Those functions are compromised by mounting pressures on marine biodiversity and ecosystems. Because of its economic and food value, fish biomass production provides an unusually direct link from biodiversity to critical ecosystem services. We used the Reef Life Survey’s global database of 4,556 standardized fish surveys to test the importance of biodiversity to fish production relative to 25 environmental drivers. Temperature, biodiversity, and human influence together explained 47% of the global variation in reef fish biomass among sites. Fish species richness and functional diversity were among the strongest predictors of fish biomass, particularly for the large-bodied species and carnivores preferred by fishers, and these biodiversity effects were robust to potentially confounding influences of sample abundance, scale, and environmental correlations. Warmer temperatures increased biomass directly, presumably by raising metabolism, and indirectly by increasing diversity, whereas temperature variability reduced biomass. Importantly, diversity and climate interact, with biomass of diverse communities less affected by rising and variable temperatures than species-poor communities. Biodiversity thus buffers global fish biomass from climate change, and conservation of marine biodiversity can stabilize fish production in a changing ocean. PMID:27185921

The seaweed holobiont: understanding seaweed-bacteria interactions.

PubMed

Egan, Suhelen; Harder, Tilmann; Burke, Catherine; Steinberg, Peter; Kjelleberg, Staffan; Thomas, Torsten

2013-05-01

Seaweeds (macroalgae) form a diverse and ubiquitous group of photosynthetic organisms that play an essential role in aquatic ecosystems. These ecosystem engineers contribute significantly to global primary production and are the major habitat formers on rocky shores in temperate waters, providing food and shelter for aquatic life. Like other eukaryotic organisms, macroalgae harbor a rich diversity of associated microorganisms with functions related to host health and defense. In particular, epiphytic bacterial communities have been reported as essential for normal morphological development of the algal host, and bacteria with antifouling properties are thought to protect chemically undefended macroalgae from detrimental, secondary colonization by other microscopic and macroscopic epibiota. This tight relationship suggests that macroalgae and epiphytic bacteria interact as a unified functional entity or holobiont, analogous to the previously suggested relationship in corals. Moreover, given that the impact of diseases in marine ecosystems is apparently increasing, understanding the role of bacteria as saprophytes and pathogens in seaweed communities may have important implications for marine management strategies. This review reports on the recent advances in the understanding of macroalgal-bacterial interactions with reference to the diversity and functional role of epiphytic bacteria in maintaining algal health, highlighting the holobiont concept. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Economic Vulnerability Assessment of U.S. Fishery Revenues to Ocean Acidification

NASA Astrophysics Data System (ADS)

Cooley, S. R.; Doney, S. C.

2008-12-01

Ocean acidification, a predictable consequence of rising anthropogenic CO2 emissions, is poised to change marine ecosystems profoundly by decreasing average ocean pH and the carbonate mineral saturation state worldwide. These conditions slow or reverse marine plant and animal calcium carbonate shell growth, thereby harming economically valuable species. In 2006, shellfish and crustaceans provided 50% of the 4 billion U.S. domestic commercial harvest value; value added to commercial fishery products contributed 35 billion to the gross national product that year. Laboratory studies have shown that ocean acidification decreases shellfish calcification; ocean acidification--driven declines in commercial shellfish and crustacean harvests between now and 2060 could decrease nationwide time-integrated primary commercial revenues by 860 million to 14 billion (net present value, 2006 dollars), depending on CO2 emissions, discount rates, biological responses, and fishery structure. This estimate excludes losses from coral reef damage and possible fishery collapses if ocean acidification pushes ecosystems past ecological tipping points. Expanding job losses and indirect economic costs will follow harvest decreases as ocean acidification broadly damages marine habitats and alters marine resource availability. Losses will harm many regions already possessing little economic resilience. The only true solution to ocean acidification is reducing atmospheric CO2 emissions, but implementing regional adaptive responses now from an ecosystem-wide, fisheries perspective will help better preserve sustainable ecosystem function and economic yields. Comprehensive management strategies must include monitoring critical fisheries, explicitly accounting for ocean acidification in management models, reducing fishing pressure and environmental stresses, and supporting regional economies most sensitive to acidification's impacts.

Bringing the ecosystem services concept into marine management decisions, supporting ecosystems-based management.

NASA Astrophysics Data System (ADS)

Tweddle, J. F.; Byg, A.; Davies, I.; Gubbins, M.; Irvine, K.; Kafas, A.; Kenter, J.; MacDonald, A.; Murray, R. B. O.; Potts, T.; Slater, A. M.; Wright, K.; Scott, B. E.

2016-02-01

The marine environment is under increasing use, putting pressure on marine ecosystems and increasing competition for space. New activities (e.g. renewable energy developments), evolving marine policies (e.g. implementation of marine protected areas), and climate change may drive changes in biodiversity and resulting ecosystem services (ES) that society and business utilise from coastal and marine systems. A process is needed that integrates ecological assessment of changes with stakeholder perceptions and valuation of ES, whilst balancing ease of application with the ability to deal with complex social-economic-ecological issues. The project "Cooperative participatory assessment of the impact of renewable technology on ecosystem services: CORPORATES" involved natural and social scientists, law and policy experts, and marine managers, with the aim of promoting more integrated decision making using ES concepts in marine management. CORPORATES developed a process to bring ES concepts into stakeholders' awareness. The interactive process, involving 2 workshops, employs interludes of knowledge exchange by experts on ecological processes underpinning ES and on law and policy. These enable mapping of benefits linked to activities, participatory system modelling, and deliberation of policy impacts on different sectors. The workshops were attended by industry representatives, regulatory/advisory partners, and other stakeholders (NGOs, SMEs, recreationalists, local government). Mixed sector groups produced new insights into links between activities and ES, and highlighted cross-sector concerns. Here we present the aspects of the process that successfully built shared understanding between industry and stakeholders of inter-linkages and interactions between ES, benefits, activities, and economic and cultural values. These methods provide an ES-based decision-support model for exchanging societal-ecological knowledge and providing stakeholder interaction in marine planning, supporting ecosystem-based management.

Bringing the ecosystem services concept into marine management decisions, supporting ecosystems-based management.

NASA Astrophysics Data System (ADS)

Tweddle, J. F.; Byg, A.; Davies, I.; Gubbins, M.; Irvine, K.; Kafas, A.; Kenter, J.; MacDonald, A.; Murray, R. B. O.; Potts, T.; Slater, A. M.; Wright, K.; Scott, B. E.

2016-12-01

The marine environment is under increasing use, putting pressure on marine ecosystems and increasing competition for space. New activities (e.g. renewable energy developments), evolving marine policies (e.g. implementation of marine protected areas), and climate change may drive changes in biodiversity and resulting ecosystem services (ES) that society and business utilise from coastal and marine systems. A process is needed that integrates ecological assessment of changes with stakeholder perceptions and valuation of ES, whilst balancing ease of application with the ability to deal with complex social-economic-ecological issues. The project "Cooperative participatory assessment of the impact of renewable technology on ecosystem services: CORPORATES" involved natural and social scientists, law and policy experts, and marine managers, with the aim of promoting more integrated decision making using ES concepts in marine management. CORPORATES developed a process to bring ES concepts into stakeholders' awareness. The interactive process, involving 2 workshops, employs interludes of knowledge exchange by experts on ecological processes underpinning ES and on law and policy. These enable mapping of benefits linked to activities, participatory system modelling, and deliberation of policy impacts on different sectors. The workshops were attended by industry representatives, regulatory/advisory partners, and other stakeholders (NGOs, SMEs, recreationalists, local government). Mixed sector groups produced new insights into links between activities and ES, and highlighted cross-sector concerns. Here we present the aspects of the process that successfully built shared understanding between industry and stakeholders of inter-linkages and interactions between ES, benefits, activities, and economic and cultural values. These methods provide an ES-based decision-support model for exchanging societal-ecological knowledge and providing stakeholder interaction in marine planning, supporting ecosystem-based management.

Simple rules can guide whether land- or ocean-based conservation will best benefit marine ecosystems.

PubMed

Saunders, Megan I; Bode, Michael; Atkinson, Scott; Klein, Carissa J; Metaxas, Anna; Beher, Jutta; Beger, Maria; Mills, Morena; Giakoumi, Sylvaine; Tulloch, Vivitskaia; Possingham, Hugh P

2017-09-01

Coastal marine ecosystems can be managed by actions undertaken both on the land and in the ocean. Quantifying and comparing the costs and benefits of actions in both realms is therefore necessary for efficient management. Here, we quantify the link between terrestrial sediment runoff and a downstream coastal marine ecosystem and contrast the cost-effectiveness of marine- and land-based conservation actions. We use a dynamic land- and sea-scape model to determine whether limited funds should be directed to 1 of 4 alternative conservation actions-protection on land, protection in the ocean, restoration on land, or restoration in the ocean-to maximise the extent of light-dependent marine benthic habitats across decadal timescales. We apply the model to a case study for a seagrass meadow in Australia. We find that marine restoration is the most cost-effective action over decadal timescales in this system, based on a conservative estimate of the rate at which seagrass can expand into a new habitat. The optimal decision will vary in different social-ecological contexts, but some basic information can guide optimal investments to counteract land- and ocean-based stressors: (1) marine restoration should be prioritised if the rates of marine ecosystem decline and expansion are similar and low; (2) marine protection should take precedence if the rate of marine ecosystem decline is high or if the adjacent catchment is relatively intact and has a low rate of vegetation decline; (3) land-based actions are optimal when the ratio of marine ecosystem expansion to decline is greater than 1:1.4, with terrestrial restoration typically the most cost-effective action; and (4) land protection should be prioritised if the catchment is relatively intact but the rate of vegetation decline is high. These rules of thumb illustrate how cost-effective conservation outcomes for connected land-ocean systems can proceed without complex modelling.

Simple rules can guide whether land- or ocean-based conservation will best benefit marine ecosystems

PubMed Central

Bode, Michael; Atkinson, Scott; Klein, Carissa J.; Metaxas, Anna; Beher, Jutta; Beger, Maria; Mills, Morena; Giakoumi, Sylvaine; Tulloch, Vivitskaia; Possingham, Hugh P.

2017-01-01

Coastal marine ecosystems can be managed by actions undertaken both on the land and in the ocean. Quantifying and comparing the costs and benefits of actions in both realms is therefore necessary for efficient management. Here, we quantify the link between terrestrial sediment runoff and a downstream coastal marine ecosystem and contrast the cost-effectiveness of marine- and land-based conservation actions. We use a dynamic land- and sea-scape model to determine whether limited funds should be directed to 1 of 4 alternative conservation actions—protection on land, protection in the ocean, restoration on land, or restoration in the ocean—to maximise the extent of light-dependent marine benthic habitats across decadal timescales. We apply the model to a case study for a seagrass meadow in Australia. We find that marine restoration is the most cost-effective action over decadal timescales in this system, based on a conservative estimate of the rate at which seagrass can expand into a new habitat. The optimal decision will vary in different social–ecological contexts, but some basic information can guide optimal investments to counteract land- and ocean-based stressors: (1) marine restoration should be prioritised if the rates of marine ecosystem decline and expansion are similar and low; (2) marine protection should take precedence if the rate of marine ecosystem decline is high or if the adjacent catchment is relatively intact and has a low rate of vegetation decline; (3) land-based actions are optimal when the ratio of marine ecosystem expansion to decline is greater than 1:1.4, with terrestrial restoration typically the most cost-effective action; and (4) land protection should be prioritised if the catchment is relatively intact but the rate of vegetation decline is high. These rules of thumb illustrate how cost-effective conservation outcomes for connected land–ocean systems can proceed without complex modelling. PMID:28877168

Comparing marine and terrestrial ecosystems: Implications for the design of coastal marine reserves

USGS Publications Warehouse

Carr, M.H.; Neigel, J.E.; Estes, J.A.; Andelman, S.; Warner, R.R.; Largier, J. L.

2003-01-01

Concepts and theory for the design and application of terrestrial reserves is based on our understanding of environmental, ecological, and evolutionary processes responsible for biological diversity and sustainability of terrestrial ecosystems and how humans have influenced these processes. How well this terrestrial-based theory can be applied toward the design and application of reserves in the coastal marine environment depends, in part, on the degree of similarity between these systems. Several marked differences in ecological and evolutionary processes exist between marine and terrestrial ecosystems as ramifications of fundamental differences in their physical environments (i.e., the relative prevalence of air and water) and contemporary patterns of human impacts. Most notably, the great extent and rate of dispersal of nutrients, materials, holoplanktonic organisms, and reproductive propagules of benthic organisms expand scales of connectivity among near-shore communities and ecosystems. Consequently, the "openness" of marine populations, communities, and ecosystems probably has marked influences on their spatial, genetic, and trophic structures and dynamics in ways experienced by only some terrestrial species. Such differences appear to be particularly significant for the kinds of organisms most exploited and targeted for protection in coastal marine ecosystems (fishes and macroinvertebrates). These and other differences imply some unique design criteria and application of reserves in the marine environment. In explaining the implications of these differences for marine reserve design and application, we identify many of the environmental and ecological processes and design criteria necessary for consideration in the development of the analytical approaches developed elsewhere in this Special Issue.

An ecological model of the Northern and Central Adriatic Sea: Analysis of ecosystem structure and fishing impacts

NASA Astrophysics Data System (ADS)

Coll, Marta; Santojanni, Alberto; Palomera, Isabel; Tudela, Sergi; Arneri, Enrico

2007-08-01

A trophic mass-balance model was developed to characterise the food web structure and functioning of the Northern and Central Adriatic Sea and to quantify the ecosystem impacts of fishing during the 1990s. Forty functional groups were described, including target and non-target fish and invertebrate groups, and three detritus groups (natural detritus, discards and by-catch of cetaceans and marine turtles). Results highlighted that there was an important coupling between pelagic-benthic production of plankton, benthic invertebrates and detritus. Organisms located at low and medium trophic levels, (i.e. benthic invertebrates, zooplankton and anchovy), as well as dolphins, were identified as keystone groups of the ecosystem. Jellyfish were an important element in terms of consumption and production of trophic flows within the ecosystem. The analysis of trophic flows of zooplankton and detritus groups indirectly underlined the importance of the microbial food web in the Adriatic Sea. Fishing activities inflicted notable impacts on the ecosystem during the 1990s, with a high gross efficiency of the fishery, a high consumption of fishable production, high exploitation rates for various target and non target species, a low trophic level of the catch and medium values of primary production required to sustain the fishery. Moreover, the analysis of Odum's ecological indicators highlighted that the ecosystem was in a low-medium developmental stage. Bottom trawling ( Strascico), mid-water trawling ( Volante) and beam trawling ( Rapido) fleets had the highest impacts on both target and non target ecological groups. On the contrary, purse seining ( Lampara) showed medium to low impacts on the ecosystem; cetaceans, marine turtles and sea birds were not significantly involved in competition with fishing activity.

Meeting Report: Methylmercury in Marine Ecosystems—From Sources to Seafood Consumers

PubMed Central

Chen, Celia Y.; Serrell, Nancy; Evers, David C.; Fleishman, Bethany J.; Lambert, Kathleen F.; Weiss, Jeri; Mason, Robert P.; Bank, Michael S.

2008-01-01

Mercury and other contaminants in coastal and open-ocean ecosystems are an issue of great concern globally and in the United States, where consumption of marine fish and shellfish is a major route of human exposure to methylmercury (MeHg). A recent National Institute of Environmental Health Sciences–Superfund Basic Research Program workshop titled “Fate and Bioavailability of Mercury in Aquatic Ecosystems and Effects on Human Exposure,” convened by the Dartmouth Toxic Metals Research Program on 15–16 November 2006 in Durham, New Hampshire, brought together human health experts, marine scientists, and ecotoxicologists to encourage cross-disciplinary discussion between ecosystem and human health scientists and to articulate research and monitoring priorities to better understand how marine food webs have become contaminated with MeHg. Although human health effects of Hg contamination were a major theme, the workshop also explored effects on marine biota. The workgroup focused on three major topics: a) the biogeochemical cycling of Hg in marine ecosystems, b) the trophic transfer and bioaccumulation of MeHg in marine food webs, and c) human exposure to Hg from marine fish and shellfish consumption. The group concluded that current understanding of Hg in marine ecosystems across a range of habitats, chemical conditions, and ocean basins is severely data limited. An integrated research and monitoring program is needed to link the processes and mechanisms of MeHg production, bioaccumulation, and transfer with MeHg exposure in humans. PMID:19079724

Effects of Detrital Subsidies on Soft-Sediment Ecosystem Function Are Transient and Source-Dependent.

PubMed

Gladstone-Gallagher, Rebecca V; Lohrer, Andrew M; Lundquist, Carolyn J; Pilditch, Conrad A

2016-01-01

Detrital subsidies from marine macrophytes are prevalent in temperate estuaries, and their role in structuring benthic macrofaunal communities is well documented, but the resulting impact on ecosystem function is not understood. We conducted a field experiment to test the effects of detrital decay on soft-sediment primary production, community metabolism and nutrient regeneration (measures of ecosystem function). Twenty four (2 m2) plots were established on an intertidal sandflat, to which we added 0 or 220 g DW m-2 of detritus from either mangroves (Avicennia marina), seagrass (Zostera muelleri), or kelp (Ecklonia radiata) (n = 6 plots per treatment). Then, after 4, 17 and 46 d we measured ecosystem function, macrofaunal community structure and sediment properties. We hypothesized that (1) detrital decay would stimulate benthic primary production either by supplying nutrients to the benthic macrophytes, or by altering the macrofaunal community; and (2) ecosystem responses would depend on the stage and rate of macrophyte decay (a function of source). Avicennia detritus decayed the slowest with a half-life (t50) of 46 d, while Zostera and Ecklonia had t50 values of 28 and 2.6 d, respectively. However, ecosystem responses were not related to these differences. Instead, we found transient effects (up to 17 d) of Avicennia and Ecklonia detritus on benthic primary production, where initially (4 d) these detrital sources suppressed primary production, but after 17 d, primary production was stimulated in Avicennia plots relative to controls. Other ecosystem function response variables and the macrofaunal community composition were not altered by the addition of detritus, but did vary with time. By sampling ecosystem function temporally, we were able to capture the in situ transient effects of detrital subsidies on important benthic ecosystem functions.

Persistence of trophic hotspots and relation to human impacts within an upwelling marine ecosystem.

PubMed

Santora, Jarrod A; Sydeman, William J; Schroeder, Isaac D; Field, John C; Miller, Rebecca R; Wells, Brian K

2017-03-01

Human impacts (e.g., fishing, pollution, and shipping) on pelagic ecosystems are increasing, causing concerns about stresses on marine food webs. Maintaining predator-prey relationships through protection of pelagic hotspots is crucial for conservation and management of living marine resources. Biotic components of pelagic, plankton-based, ecosystems exhibit high variability in abundance in time and space (i.e., extreme patchiness), requiring investigation of persistence of abundance across trophic levels to resolve trophic hotspots. Using a 26-yr record of indicators for primary production, secondary (zooplankton and larval fish), and tertiary (seabirds) consumers, we show distributions of trophic hotspots in the southern California Current Ecosystem result from interactions between a strong upwelling center and a productive retention zone with enhanced nutrients, which concentrate prey and predators across multiple trophic levels. Trophic hotspots also overlap with human impacts, including fisheries extraction of coastal pelagic and groundfish species, as well as intense commercial shipping traffic. Spatial overlap of trophic hotspots with fisheries and shipping increases vulnerability of the ecosystem to localized depletion of forage fish, ship strikes on marine mammals, and pollution. This study represents a critical step toward resolving pelagic areas of high conservation interest for planktonic ecosystems and may serve as a model for other ocean regions where ecosystem-based management and marine spatial planning of pelagic ecosystems is warranted. © 2016 by the Ecological Society of America.

[Management of large marine ecosystem based on ecosystem approach].

PubMed

Chu, Jian-song

2011-09-01

Large marine ecosystem (LME) is a large area of ocean characterized by distinct oceanology and ecology. Its natural characteristics require management based on ecosystem approach. A series of international treaties and regulations definitely or indirectly support that it should adopt ecosystem approach to manage LME to achieve the sustainable utilization of marine resources. In practices, some countries such as Canada, Australia, and U.S.A. have adopted ecosystem-based approach to manage their oceans, and some international organizations such as global environment fund committee have carried out a number of LME programs based on ecosystem approach. Aiming at the sustainable development of their fisheries, the regional organizations such as Caribbean Community have established regional fisheries mechanism. However, the adoption of ecosystem approach to manage LME is not only a scientific and legal issue, but also a political matter largely depending on the political will and the mutual cooperation degree of related countries.

Taxonomic and functional diversity increase the aesthetic value of coralligenous reefs

PubMed Central

Tribot, Anne-Sophie; Mouquet, Nicolas; Villéger, Sébastien; Raymond, Michel; Hoff, Fabrice; Boissery, Pierre; Holon, Florian; Deter, Julie

2016-01-01

The aesthetic value of landscapes contributes to human well-being. However, studies which have investigated the link between biodiversity and ecosystem services have not taken aesthetic value into account. In this study we evaluated how the aesthetics of coralligenous reefs, a key marine ecosystem in the Mediterranean, is perceived by the general public and how aesthetic preferences are related to biodiversity facets (taxonomic, phylogenetic and functional diversities). We performed both biodiversity measures and online-surveys of aesthetic perception on photographic quadrats sampled along the French Mediterranean coast. Our results show that species richness and functional richness have a significant positive effect on aesthetic value. Most of the ecological literature, exploring the relationship between biodiversity and ecosystem functioning and service has focused so far on ‘economical’ aspects of biodiversity (provision or regulation). Our results illustrate that cultural facets, such as ‘beauty’, should also be central in our motivations to preserve ecological diversity. PMID:27677850

How can we identify and communicate the ecological value of deep-sea ecosystem services?

PubMed

Jobstvogt, Niels; Townsend, Michael; Witte, Ursula; Hanley, Nick

2014-01-01

Submarine canyons are considered biodiversity hotspots which have been identified for their important roles in connecting the deep sea with shallower waters. To date, a huge gap exists between the high importance that scientists associate with deep-sea ecosystem services and the communication of this knowledge to decision makers and to the wider public, who remain largely ignorant of the importance of these services. The connectivity and complexity of marine ecosystems makes knowledge transfer very challenging, and new communication tools are necessary to increase understanding of ecological values beyond the science community. We show how the Ecosystem Principles Approach, a method that explains the importance of ocean processes via easily understandable ecological principles, might overcome this challenge for deep-sea ecosystem services. Scientists were asked to help develop a list of clear and concise ecosystem principles for the functioning of submarine canyons through a Delphi process to facilitate future transfers of ecological knowledge. These ecosystem principles describe ecosystem processes, link such processes to ecosystem services, and provide spatial and temporal information on the connectivity between deep and shallow waters. They also elucidate unique characteristics of submarine canyons. Our Ecosystem Principles Approach was successful in integrating ecological information into the ecosystem services assessment process. It therefore has a high potential to be the next step towards a wider implementation of ecological values in marine planning. We believe that successful communication of ecological knowledge is the key to a wider public support for ocean conservation, and that this endeavour has to be driven by scientists in their own interest as major deep-sea stakeholders.

How Can We Identify and Communicate the Ecological Value of Deep-Sea Ecosystem Services?

PubMed Central

Jobstvogt, Niels; Townsend, Michael; Witte, Ursula; Hanley, Nick

2014-01-01

Submarine canyons are considered biodiversity hotspots which have been identified for their important roles in connecting the deep sea with shallower waters. To date, a huge gap exists between the high importance that scientists associate with deep-sea ecosystem services and the communication of this knowledge to decision makers and to the wider public, who remain largely ignorant of the importance of these services. The connectivity and complexity of marine ecosystems makes knowledge transfer very challenging, and new communication tools are necessary to increase understanding of ecological values beyond the science community. We show how the Ecosystem Principles Approach, a method that explains the importance of ocean processes via easily understandable ecological principles, might overcome this challenge for deep-sea ecosystem services. Scientists were asked to help develop a list of clear and concise ecosystem principles for the functioning of submarine canyons through a Delphi process to facilitate future transfers of ecological knowledge. These ecosystem principles describe ecosystem processes, link such processes to ecosystem services, and provide spatial and temporal information on the connectivity between deep and shallow waters. They also elucidate unique characteristics of submarine canyons. Our Ecosystem Principles Approach was successful in integrating ecological information into the ecosystem services assessment process. It therefore has a high potential to be the next step towards a wider implementation of ecological values in marine planning. We believe that successful communication of ecological knowledge is the key to a wider public support for ocean conservation, and that this endeavour has to be driven by scientists in their own interest as major deep-sea stakeholders. PMID:25055119

Changes in Marine Environments and Responses of Ecosystem Dynamics in the East Asian Pacific

NASA Astrophysics Data System (ADS)

Ogawa, Hiroshi; Saito, Hiroaki; Ju, Se-Jong

2014-02-01

At an international symposium on the marine systems of the Pacific region of East Asia, scientists concluded that changes in the ocean environment are having a significant effect on biogeochemical cycles and ecosystems and, consequently, on humans and the food supply. The meeting, the 6th China-Japan-Korea (CJK) Integrated Marine Biogeochemistry and Ecosystem Research symposium, was held in Japan at the University of Tokyo.

Modeling dynamic interactions and coherence between marine zooplankton and fishes linked to environmental variability

NASA Astrophysics Data System (ADS)

Liu, Hui; Fogarty, Michael J.; Hare, Jonathan A.; Hsieh, Chih-hao; Glaser, Sarah M.; Ye, Hao; Deyle, Ethan; Sugihara, George

2014-03-01

The dynamics of marine fishes are closely related to lower trophic levels and the environment. Quantitatively understanding ecosystem dynamics linking environmental variability and prey resources to exploited fishes is crucial for ecosystem-based management of marine living resources. However, standard statistical models typically grounded in the concept of linear system may fail to capture the complexity of ecological processes. We have attempted to model ecosystem dynamics using a flexible, nonparametric class of nonlinear forecasting models. We analyzed annual time series of four environmental indices, 22 marine copepod taxa, and four ecologically and commercially important fish species during 1977 to 2009 on Georges Bank, a highly productive and intensively studied area of the northeast U.S. continental shelf ecosystem. We examined the underlying dynamic features of environmental indices and copepods, quantified the dynamic interactions and coherence with fishes, and explored the potential control mechanisms of ecosystem dynamics from a nonlinear perspective. We found: (1) the dynamics of marine copepods and environmental indices exhibiting clear nonlinearity; (2) little evidence of complex dynamics across taxonomic levels of copepods; (3) strong dynamic interactions and coherence between copepods and fishes; and (4) the bottom-up forcing of fishes and top-down control of copepods coexisting as target trophic levels vary. These findings highlight the nonlinear interactions among ecosystem components and the importance of marine zooplankton to fish populations which point to two forcing mechanisms likely interactively regulating the ecosystem dynamics on Georges Bank under a changing environment.

Chemical ecology of marine angiosperms: opportunities at the interface of marine and terrestrial systems.

PubMed

Sieg, R Drew; Kubanek, Julia

2013-06-01

This review examines the state of the field for chemically mediated interactions involving marine angiosperms (seagrasses, mangroves, and salt marsh angiosperms). Small-scale interactions among these plants and their herbivores, pathogens, fouling organisms, and competitors are explored, as are community-level effects of plant secondary metabolites. At larger spatial scales, secondary metabolites from marine angiosperms function as reliable cues for larval settlement, molting, or habitat selection by fish and invertebrates, and can influence community structure and ecosystem function. Several recent studies illustrate the importance of chemical defenses from these plants that deter feeding by herbivores and infection by pathogens, but the extent to which allelopathic compounds kill or inhibit the growth of competitors is less clear. While some phenolic compounds such as ferulic acid and caffeic acid act as critical defenses against herbivores and pathogens, we find that a high total concentration of phenolic compounds within bulk plant tissues is not a strong predictor of defense. Residual chemical defenses prevent shredding or degradation of plant detritus by detritivores and microbes, delaying the time before plant matter can enter the microbial loop. Mangroves, marsh plants, and seagrasses remain plentiful sources of new natural products, but ecological functions are known for only a small proportion of these compounds. As new analytical techniques are incorporated into ecological studies, opportunities are emerging for chemical ecologists to test how subtle environmental cues affect the production and release of marine angiosperm chemical defenses or signaling molecules. Throughout this review, we point to areas for future study, highlighting opportunities for new directions in chemical ecology that will advance our understanding of ecological interactions in these valuable ecosystems.

Archaeology Meets Marine Ecology: The Antiquity of Maritime Cultures and Human Impacts on Marine Fisheries and Ecosystems

NASA Astrophysics Data System (ADS)

Erlandson, Jon M.; Rick, Torben C.

2010-01-01

Interdisciplinary study of coastal archaeological sites provides a wealth of information on the ecology and evolution of ancient marine animal populations, the structure of past marine ecosystems, and the history of human impacts on coastal fisheries. In this paper, we review recent methodological developments in the archaeology and historical ecology of coastal regions around the world. Using two case studies, we examine (a) a deep history of anthropogenic effects on the marine ecosystems of California's Channel Islands through the past 12,000 years and (b) geographic variation in the effects of human fishing on Pacific Island peoples who spread through Oceania during the late Holocene. These case studies—the first focused on hunter-gatherers, the second on maritime horticulturalists—provide evidence for shifting baselines and timelines, documenting a much deeper anthropogenic influence on many coastal ecosystems and fisheries than considered by most ecologists, conservation biologists, and fisheries managers.

Archaeology meets marine ecology: the antiquity of maritime cultures and human impacts on marine fisheries and ecosystems.

PubMed

Erlandson, Jon M; Rick, Torben C

2010-01-01

Interdisciplinary study of coastal archaeological sites provides a wealth of information on the ecology and evolution of ancient marine animal populations, the structure of past marine ecosystems, and the history of human impacts on coastal fisheries. In this paper, we review recent methodological developments in the archaeology and historical ecology of coastal regions around the world. Using two case studies, we examine (a) a deep history of anthropogenic effects on the marine ecosystems of California's Channel Islands through the past 12,000 years and (b) geographic variation in the effects of human fishing on Pacific Island peoples who spread through Oceania during the late Holocene. These case studies--the first focused on hunter-gatherers, the second on maritime horticulturalists-provide evidence for shifting baselines and timelines, documenting a much deeper anthropogenic influence on many coastal ecosystems and fisheries than considered by most ecologists, conservation biologists, and fisheries managers.

THE RESPONSE OF MARINE ECOSYSTEMS TO CLIMATE VARIABILITY ASSOCIATED WITH THE NORTH ATLANTIC OSCILLATION

EPA Science Inventory

A strong association is documented between variability of the North Atlantic Oscillation (NAO) and changes in various trophic levels of the marine ecosystems of the North Atlantic. Examples are presented for phytoplankton, zooplankton, benthos, fish, marine diseases, whales and s...

Management of the marine environment: integrating ecosystem services and societal benefits with the DPSIR framework in a systems approach.

PubMed

Atkins, Jonathan P; Burdon, Daryl; Elliott, Mike; Gregory, Amanda J

2011-02-01

Ever increasing and diverse use of the marine environment is leading to human-induced changes in marine life, habitats and landscapes, making necessary the development of marine policy that considers all members of the user community and addresses current, multiple, interacting uses. Taking a systems approach incorporating an understanding of The Ecosystem Approach, we integrate the DPSIR framework with ecosystem services and societal benefits, and the focus this gives allows us to create a specific framework for supporting decision making in the marine environment. Based on a linking of these three concepts, we present a set of basic postulates for the management of the marine environment and emphasise that these postulates should hold for marine management to be achieved. We illustrate these concepts using two case studies: the management of marine aggregates extraction in UK waters and the management of marine biodiversity at Flamborough Head, UK. Copyright © 2010 Elsevier Ltd. All rights reserved.

Exploring local adaptation and the ocean acidification seascape - studies in the California Current Large Marine Ecosystem

NASA Astrophysics Data System (ADS)

Hofmann, G. E.; Evans, T. G.; Kelly, M. W.; Padilla-Gamiño, J. L.; Blanchette, C. A.; Washburn, L.; Chan, F.; McManus, M. A.; Menge, B. A.; Gaylord, B.; Hill, T. M.; Sanford, E.; LaVigne, M.; Rose, J. M.; Kapsenberg, L.; Dutton, J. M.

2014-02-01

The California Current Large Marine Ecosystem (CCLME), a temperate marine region dominated by episodic upwelling, is predicted to experience rapid environmental change in the future due to ocean acidification. The aragonite saturation state within the California Current System is predicted to decrease in the future with near-permanent undersaturation conditions expected by the year 2050. Thus, the CCLME is a critical region to study due to the rapid rate of environmental change that resident organisms will experience and because of the economic and societal value of this coastal region. Recent efforts by a research consortium - the Ocean Margin Ecosystems Group for Acidification Studies (OMEGAS) - has begun to characterize a portion of the CCLME; both describing the spatial mosaic of pH in coastal waters and examining the responses of key calcification-dependent benthic marine organisms to natural variation in pH and to changes in carbonate chemistry that are expected in the coming decades. In this review, we present the OMEGAS strategy of co-locating sensors and oceanographic observations with biological studies on benthic marine invertebrates, specifically measurements of functional traits such as calcification-related processes and genetic variation in populations that are locally adapted to conditions in a particular region of the coast. Highlighted in this contribution are (1) the OMEGAS sensor network that spans the west coast of the US from central Oregon to southern California, (2) initial findings of the carbonate chemistry amongst the OMEGAS study sites, and (3) an overview of the biological data that describes the acclimatization and the adaptation capacity of key benthic marine invertebrates within the CCLME.

Seventy-one important questions for the conservation of marine biodiversity.

PubMed

Parsons, E C M; Favaro, Brett; Aguirre, A Alonso; Bauer, Amy L; Blight, Louise K; Cigliano, John A; Coleman, Melinda A; Côté, Isabelle M; Draheim, Megan; Fletcher, Stephen; Foley, Melissa M; Jefferson, Rebecca; Jones, Miranda C; Kelaher, Brendan P; Lundquist, Carolyn J; McCarthy, Julie-Beth; Nelson, Anne; Patterson, Katheryn; Walsh, Leslie; Wright, Andrew J; Sutherland, William J

2014-10-01

The ocean provides food, economic activity, and cultural value for a large proportion of humanity. Our knowledge of marine ecosystems lags behind that of terrestrial ecosystems, limiting effective protection of marine resources. We describe the outcome of 2 workshops in 2011 and 2012 to establish a list of important questions, which, if answered, would substantially improve our ability to conserve and manage the world's marine resources. Participants included individuals from academia, government, and nongovernment organizations with broad experience across disciplines, marine ecosystems, and countries that vary in levels of development. Contributors from the fields of science, conservation, industry, and government submitted questions to our workshops, which we distilled into a list of priority research questions. Through this process, we identified 71 key questions. We grouped these into 8 subject categories, each pertaining to a broad component of marine conservation: fisheries, climate change, other anthropogenic threats, ecosystems, marine citizenship, policy, societal and cultural considerations, and scientific enterprise. Our questions address many issues that are specific to marine conservation, and will serve as a road map to funders and researchers to develop programs that can greatly benefit marine conservation. © 2014 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of The Society for the Study of Evolution.

Relationships between meiofaunal biodiversity and prokaryotic heterotrophic production in different tropical habitats and oceanic regions.

PubMed

Pusceddu, Antonio; Gambi, Cristina; Corinaldesi, Cinzia; Scopa, Mariaspina; Danovaro, Roberto

2014-01-01

Tropical marine ecosystems are among the most diverse of the world oceans, so that assessing the linkages between biodiversity and ecosystem functions (BEF) is a crucial step to predict consequences of biodiversity loss. Most BEF studies in marine ecosystems have been carried out on macrobenthic diversity, whereas the influence of the meiofauna on ecosystem functioning has received much less attention. We compared meiofaunal and nematode biodiversity and prokaryotic heterotrophic production across seagrass, mangrove and reef sediments in the Caribbean, Celebes and Red Seas. For all variables we report the presence of differences among habitats within the same region, and among regions within the same habitat. In all regions, the richness of meiofaunal taxa in reef and seagrass sediments is higher than in mangrove sediments. The sediments of the Celebes Sea show the highest meiofaunal biodiversity. The composition of meiofaunal assemblages varies significantly among habitats in the same region. The nematode beta diversity among habitats within the same region is higher than the beta diversity among regions. Although one site per habitat was considered in each region, these results suggest that the composition of meiofaunal assemblages varies primarily among biogeographic regions, whereas the composition of nematode assemblages varies more considerably among habitats. Meiofauna and nematode biodiversity and prokaryotic heterotrophic production, even after the removal of covariate effects linked with longitude and the quantity and nutritional quality of organic matter, are positively and linearly linked both across regions and within each habitat type. Our results confirm that meiofauna and nematode biodiversity may influence benthic prokaryotic activity, which, in turn, implies that diversity loss could have negative impacts on ecosystem functioning in these systems.

Recommendations for developing and applying genetic tools to assess and manage biological invasions in marine ecosystems

EPA Science Inventory

The European Union’s Marine Strategy Framework Directive (MSFD) aims to adopt integrated ecosystem management approaches to achieve or maintain “Good Environmental Status” for marine waters, habitats and resources, including mitigation of the negative effects of non-indigenous sp...

Fishing down nutrients on coral reefs.

PubMed

Allgeier, Jacob E; Valdivia, Abel; Cox, Courtney; Layman, Craig A

2016-08-16

Fishing is widely considered a leading cause of biodiversity loss in marine environments, but the potential effect on ecosystem processes, such as nutrient fluxes, is less explored. Here, we test how fishing on Caribbean coral reefs influences biodiversity and ecosystem functions provided by the fish community, that is, fish-mediated nutrient capacity. Specifically, we modelled five processes of nutrient storage (in biomass) and supply (via excretion) of nutrients, as well as a measure of their multifunctionality, onto 143 species of coral reef fishes across 110 coral reef fish communities. These communities span a gradient from extreme fishing pressure to protected areas with little to no fishing. We find that in fished sites fish-mediated nutrient capacity is reduced almost 50%, despite no substantial changes in the number of species. Instead, changes in community size and trophic structure were the primary cause of shifts in ecosystem function. These findings suggest that a broader perspective that incorporates predictable impacts of fishing pressure on ecosystem function is imperative for effective coral reef conservation and management.

An Integrated Multivariable Visualization Tool for Marine Sanctuary Climate Assessments

NASA Astrophysics Data System (ADS)

Shein, K. A.; Johnston, S.; Stachniewicz, J.; Duncan, B.; Cecil, D.; Ansari, S.; Urzen, M.

2012-12-01

The comprehensive development and use of ecological climate impact assessments by ecosystem managers can be limited by data access and visualization methods that require a priori knowledge about the various large and complex climate data products necessary to those impact assessments. In addition, it can be difficult to geographically and temporally integrate climate and ecological data to fully characterize climate-driven ecological impacts. To address these considerations, we have enhanced and extended the functionality of the NOAA National Climatic Data Center's Weather and Climate Toolkit (WCT). The WCT is a freely available Java-based tool designed to access and display NCDC's georeferenced climate data products (e.g., satellite, radar, and reanalysis gridded data). However, the WCT requires users already know how to obtain the data products, which products are preferred for a given variable, and which products are most relevant to their needs. Developed in cooperation with research and management customers at the Gulf of the Farallones National Marine Sanctuary, the Integrated Marine Protected Area Climate Tools (IMPACT) modification to the WCT simplifies or eliminates these requirements, while simultaneously adding core analytical functionality to the tool. Designed for use by marine ecosystem managers, WCT-IMPACT accesses a suite of data products that have been identified as relevant to marine ecosystem climate impact assessments, such as NOAA's Climate Data Records. WCT-IMPACT regularly crops these products to the geographic boundaries of each included marine protected area (MPA), and those clipped regions are processed to produce MPA-specific analytics. The tool retrieves the most appropriate data files based on the user selection of MPA, environmental variable(s), and time frame. Once the data are loaded, they may be visualized, explored, analyzed, and exported to other formats (e.g., Google KML). Multiple variables may be simultaneously visualized using a 4-panel display and compared via a variety of statistics such as difference, probability, or correlation maps.; NCDC's Weather and Climate Toolkit image of NARR-A non-convective cloud cover (%) over the Pacific Coast on June 17, 2012 at 09:00 GMT.

Assimilation of Ocean-Color Plankton Functional Types to Improve Marine Ecosystem Simulations

NASA Astrophysics Data System (ADS)

Ciavatta, S.; Brewin, R. J. W.; Skákala, J.; Polimene, L.; de Mora, L.; Artioli, Y.; Allen, J. I.

2018-02-01

We assimilated phytoplankton functional types (PFTs) derived from ocean color into a marine ecosystem model, to improve the simulation of biogeochemical indicators and emerging properties in a shelf sea. Error-characterized chlorophyll concentrations of four PFTs (diatoms, dinoflagellates, nanoplankton, and picoplankton), as well as total chlorophyll for comparison, were assimilated into a physical-biogeochemical model of the North East Atlantic, applying a localized Ensemble Kalman filter. The reanalysis simulations spanned the years 1998-2003. The skill of the reference and reanalysis simulations in estimating ocean color and in situ biogeochemical data were compared by using robust statistics. The reanalysis outperformed both the reference and the assimilation of total chlorophyll in estimating the ocean-color PFTs (except nanoplankton), as well as the not-assimilated total chlorophyll, leading the model to simulate better the plankton community structure. Crucially, the reanalysis improved the estimates of not-assimilated in situ data of PFTs, as well as of phosphate and pCO2, impacting the simulation of the air-sea carbon flux. However, the reanalysis increased further the model overestimation of nitrate, in spite of increases in plankton nitrate uptake. The method proposed here is easily adaptable for use with other ecosystem models that simulate PFTs, for, e.g., reanalysis of carbon fluxes in the global ocean and for operational forecasts of biogeochemical indicators in shelf-sea ecosystems.

Anthropogenic impacts on marine ecosystems in Antarctica.

PubMed

Aronson, Richard B; Thatje, Sven; McClintock, James B; Hughes, Kevin A

2011-03-01

Antarctica is the most isolated continent on Earth, but it has not escaped the negative impacts of human activity. The unique marine ecosystems of Antarctica and their endemic faunas are affected on local and regional scales by overharvesting, pollution, and the introduction of alien species. Global climate change is also having deleterious impacts: rising sea temperatures and ocean acidification already threaten benthic and pelagic food webs. The Antarctic Treaty System can address local- to regional-scale impacts, but it does not have purview over the global problems that impinge on Antarctica, such as emissions of greenhouse gases. Failure to address human impacts simultaneously at all scales will lead to the degradation of Antarctic marine ecosystems and the homogenization of their composition, structure, and processes with marine ecosystems elsewhere. © 2011 New York Academy of Sciences.

Extraordinary aggressive behavior from the giant coral reef fish, Bolbometopon muricatum, in a remote marine reserve.

PubMed

Muñoz, Roldan C; Zgliczynski, Brian J; Laughlin, Joseph L; Teer, Bradford Z

2012-01-01

Human impacts to terrestrial and marine communities are widespread and typically begin with the local extirpation of large-bodied animals. In the marine environment, few pristine areas relatively free of human impact remain to provide baselines of ecosystem function and goals for restoration efforts. Recent comparisons of remote and/or protected coral reefs versus impacted sites suggest remote systems are dominated by apex predators, yet in these systems the ecological role of non-predatory, large-bodied, highly vulnerable species such as the giant bumphead parrotfish (Bolbometopon muricatum) has received less attention. Overfishing of Bolbometopon has lead to precipitous declines in population density and avoidance of humans throughout its range, contributing to its status as a candidate species under the U. S. Endangered Species Act and limiting opportunities to study unexploited populations. Here we show that extraordinary ecological processes, such as violent headbutting contests by the world's largest parrotfish, can be revealed by studying unexploited ecosystems, such as the coral reefs of Wake Atoll where we studied an abundant population of Bolbometopon. Bolbometopon is among the largest of coral reef fishes and is a well known, charismatic species, yet to our knowledge, no scientific documentation of ritualized headbutting exists for marine fishes. Our observations of aggressive headbutting by Bolbometopon underscore that remote locations and marine reserves, by inhibiting negative responses to human observers and by allowing the persistence of historical conditions, can provide valuable opportunities to study ecosystems in their natural state, thereby facilitating the discovery, conservation, and interpretation of a range of sometimes remarkable behavioral and ecological processes.

Extraordinary Aggressive Behavior from the Giant Coral Reef Fish, Bolbometopon muricatum, in a Remote Marine Reserve

PubMed Central

Muñoz, Roldan C.; Zgliczynski, Brian J.; Laughlin, Joseph L.; Teer, Bradford Z.

2012-01-01

Human impacts to terrestrial and marine communities are widespread and typically begin with the local extirpation of large-bodied animals. In the marine environment, few pristine areas relatively free of human impact remain to provide baselines of ecosystem function and goals for restoration efforts. Recent comparisons of remote and/or protected coral reefs versus impacted sites suggest remote systems are dominated by apex predators, yet in these systems the ecological role of non-predatory, large-bodied, highly vulnerable species such as the giant bumphead parrotfish (Bolbometopon muricatum) has received less attention. Overfishing of Bolbometopon has lead to precipitous declines in population density and avoidance of humans throughout its range, contributing to its status as a candidate species under the U. S. Endangered Species Act and limiting opportunities to study unexploited populations. Here we show that extraordinary ecological processes, such as violent headbutting contests by the world’s largest parrotfish, can be revealed by studying unexploited ecosystems, such as the coral reefs of Wake Atoll where we studied an abundant population of Bolbometopon. Bolbometopon is among the largest of coral reef fishes and is a well known, charismatic species, yet to our knowledge, no scientific documentation of ritualized headbutting exists for marine fishes. Our observations of aggressive headbutting by Bolbometopon underscore that remote locations and marine reserves, by inhibiting negative responses to human observers and by allowing the persistence of historical conditions, can provide valuable opportunities to study ecosystems in their natural state, thereby facilitating the discovery, conservation, and interpretation of a range of sometimes remarkable behavioral and ecological processes. PMID:22701606

Habitat structure mediates biodiversity effects on ecosystem properties

PubMed Central

Godbold, J. A.; Bulling, M. T.; Solan, M.

2011-01-01

Much of what we know about the role of biodiversity in mediating ecosystem processes and function stems from manipulative experiments, which have largely been performed in isolated, homogeneous environments that do not incorporate habitat structure or allow natural community dynamics to develop. Here, we use a range of habitat configurations in a model marine benthic system to investigate the effects of species composition, resource heterogeneity and patch connectivity on ecosystem properties at both the patch (bioturbation intensity) and multi-patch (nutrient concentration) scale. We show that allowing fauna to move and preferentially select patches alters local species composition and density distributions, which has negative effects on ecosystem processes (bioturbation intensity) at the patch scale, but overall positive effects on ecosystem functioning (nutrient concentration) at the multi-patch scale. Our findings provide important evidence that community dynamics alter in response to localized resource heterogeneity and that these small-scale variations in habitat structure influence species contributions to ecosystem properties at larger scales. We conclude that habitat complexity forms an important buffer against disturbance and that contemporary estimates of the level of biodiversity required for maintaining future multi-functional systems may need to be revised. PMID:21227969

Habitat structure mediates biodiversity effects on ecosystem properties.

PubMed

Godbold, J A; Bulling, M T; Solan, M

2011-08-22

Much of what we know about the role of biodiversity in mediating ecosystem processes and function stems from manipulative experiments, which have largely been performed in isolated, homogeneous environments that do not incorporate habitat structure or allow natural community dynamics to develop. Here, we use a range of habitat configurations in a model marine benthic system to investigate the effects of species composition, resource heterogeneity and patch connectivity on ecosystem properties at both the patch (bioturbation intensity) and multi-patch (nutrient concentration) scale. We show that allowing fauna to move and preferentially select patches alters local species composition and density distributions, which has negative effects on ecosystem processes (bioturbation intensity) at the patch scale, but overall positive effects on ecosystem functioning (nutrient concentration) at the multi-patch scale. Our findings provide important evidence that community dynamics alter in response to localized resource heterogeneity and that these small-scale variations in habitat structure influence species contributions to ecosystem properties at larger scales. We conclude that habitat complexity forms an important buffer against disturbance and that contemporary estimates of the level of biodiversity required for maintaining future multi-functional systems may need to be revised.

Hybrid modeling approach for the northern Adriatic watershed management.

PubMed

Volf, Goran; Atanasova, Nataša; Škerjanec, Mateja; Ožanić, Nevenka

2018-04-23

Northern Adriatic (NA) is one of the most productive parts of the Mediterranean Sea due to vast nutrient discharges from the contributing watershed. To understand better the excess of nutrients as stressors to the state of the marine ecosystem, a hybrid modeling approach following the DPSIR framework and terminology was developed, linking: 1) the AVGWLF model for modeling the pressures, i.e. nutrients originating from the watershed caused by two major drivers (urbanization and agriculture), 2) the ML tool MTSMOTI for inducing a model tree connecting the pressures with the marine ecosystem state, and 3) the water quality index, TRIX, equation to evaluate the trophic state of the marine ecosystem. Data used for the modeling purpose comprised GIS layers (i.e., digital terrain model, land use/cover data, soil map, locations of hydro-meteorological stations and WWTPs), time series data (i.e., hydro-meteorological data and nutrient concentrations), and statistical data (i.e., number of inhabitants, connections to wastewater treatment, livestock statistics, etc.) as well as physical, chemical and biological parameters, measured at six marine water monitoring stations, located between the Po River delta (Italy) and the city of Rovinj (west Istrian coast, Croatia). Using the model, seven watershed management scenarios related to wastewater treatment and agricultural activities were evaluated for their influence on the state of the NA marine ecosystem. According to the results, the gradual implementation of the UWWTD in the last 10years contributed significantly to the preservation and improvement of the NA marine ecosystem state. However, despite the full implementation of the UWWTD, the state of the NA marine ecosystem could deteriorate in case of increased nutrient loads from agriculture. Since the UWWTD is already close to its full implementation, NA watershed management should focus on controlling agricultural activities in order to maintain 'high' state of the NA marine ecosystem. Copyright © 2018 Elsevier B.V. All rights reserved.

Current status and future prospects for the assessment of marine and coastal ecosystem services: a systematic review.

PubMed

Liquete, Camino; Piroddi, Chiara; Drakou, Evangelia G; Gurney, Leigh; Katsanevakis, Stelios; Charef, Aymen; Egoh, Benis

2013-01-01

Research on ecosystem services has grown exponentially during the last decade. Most of the studies have focused on assessing and mapping terrestrial ecosystem services highlighting a knowledge gap on marine and coastal ecosystem services (MCES) and an urgent need to assess them. We reviewed and summarized existing scientific literature related to MCES with the aim of extracting and classifying indicators used to assess and map them. We found 145 papers that specifically assessed marine and coastal ecosystem services from which we extracted 476 indicators. Food provision, in particular fisheries, was the most extensively analyzed MCES while water purification and coastal protection were the most frequently studied regulating and maintenance services. Also recreation and tourism under the cultural services was relatively well assessed. We highlight knowledge gaps regarding the availability of indicators that measure the capacity, flow or benefit derived from each ecosystem service. The majority of the case studies was found in mangroves and coastal wetlands and was mainly concentrated in Europe and North America. Our systematic review highlighted the need of an improved ecosystem service classification for marine and coastal systems, which is herein proposed with definitions and links to previous classifications. This review summarizes the state of available information related to ecosystem services associated with marine and coastal ecosystems. The cataloging of MCES indicators and the integrated classification of MCES provided in this paper establish a background that can facilitate the planning and integration of future assessments. The final goal is to establish a consistent structure and populate it with information able to support the implementation of biodiversity conservation policies.

The role of a dominant predator in shaping biodiversity over space and time in a marine ecosystem.

PubMed

Ellingsen, Kari E; Anderson, Marti J; Shackell, Nancy L; Tveraa, Torkild; Yoccoz, Nigel G; Frank, Kenneth T

2015-09-01

1. Exploitation of living marine resources has resulted in major changes to populations of targeted species and functional groups of large-bodied species in the ocean. However, the effects of overfishing and collapse of large top predators on the broad-scale biodiversity of oceanic ecosystems remain largely unexplored. 2. Populations of the Atlantic cod (Gadus morhua) were overfished and several collapsed in the early 1990s across Atlantic Canada, providing a unique opportunity to study potential ecosystem-level effects of the reduction of a dominant predator on fish biodiversity, and to identify how such effects might interact with other environmental factors, such as changes in climate, over time. 3. We combined causal modelling with model selection and multimodel inference to analyse 41 years of fishery-independent survey data (1970-2010) and quantify ecosystem-level effects of overfishing and climate variation on the biodiversity of fishes across a broad area (172 000 km(2) ) of the Scotian Shelf. 4. We found that alpha and beta diversity increased with decreases in cod occurrence; fish communities were less homogeneous and more variable in systems where cod no longer dominated. These effects were most pronounced in the colder north-eastern parts of the Scotian Shelf. 5. Our results provide strong evidence that intensive harvesting (and collapse) of marine apex predators can have large impacts on biodiversity, with far-reaching consequences for ecological stability across an entire ecosystem. © 2015 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.

Ecohydrodynamics of cold-water coral reefs: a case study of the Mingulay Reef Complex (western Scotland).

PubMed

Moreno Navas, Juan; Miller, Peter I; Miller, Peter L; Henry, Lea-Anne; Hennige, Sebastian J; Roberts, J Murray

2014-01-01

Ecohydrodynamics investigates the hydrodynamic constraints on ecosystems across different temporal and spatial scales. Ecohydrodynamics play a pivotal role in the structure and functioning of marine ecosystems, however the lack of integrated complex flow models for deep-water ecosystems beyond the coastal zone prevents further synthesis in these settings. We present a hydrodynamic model for one of Earth's most biologically diverse deep-water ecosystems, cold-water coral reefs. The Mingulay Reef Complex (western Scotland) is an inshore seascape of cold-water coral reefs formed by the scleractinian coral Lophelia pertusa. We applied single-image edge detection and composite front maps using satellite remote sensing, to detect oceanographic fronts and peaks of chlorophyll a values that likely affect food supply to corals and other suspension-feeding fauna. We also present a high resolution 3D ocean model to incorporate salient aspects of the regional and local oceanography. Model validation using in situ current speed, direction and sea elevation data confirmed the model's realistic representation of spatial and temporal aspects of circulation at the reef complex including a tidally driven current regime, eddies, and downwelling phenomena. This novel combination of 3D hydrodynamic modelling and remote sensing in deep-water ecosystems improves our understanding of the temporal and spatial scales of ecological processes occurring in marine systems. The modelled information has been integrated into a 3D GIS, providing a user interface for visualization and interrogation of results that allows wider ecological application of the model and that can provide valuable input for marine biodiversity and conservation applications.

Ecohydrodynamics of Cold-Water Coral Reefs: A Case Study of the Mingulay Reef Complex (Western Scotland)

PubMed Central

Navas, Juan Moreno; Miller, Peter L.; Henry, Lea-Anne; Hennige, Sebastian J.; Roberts, J. Murray

2014-01-01

Ecohydrodynamics investigates the hydrodynamic constraints on ecosystems across different temporal and spatial scales. Ecohydrodynamics play a pivotal role in the structure and functioning of marine ecosystems, however the lack of integrated complex flow models for deep-water ecosystems beyond the coastal zone prevents further synthesis in these settings. We present a hydrodynamic model for one of Earth's most biologically diverse deep-water ecosystems, cold-water coral reefs. The Mingulay Reef Complex (western Scotland) is an inshore seascape of cold-water coral reefs formed by the scleractinian coral Lophelia pertusa. We applied single-image edge detection and composite front maps using satellite remote sensing, to detect oceanographic fronts and peaks of chlorophyll a values that likely affect food supply to corals and other suspension-feeding fauna. We also present a high resolution 3D ocean model to incorporate salient aspects of the regional and local oceanography. Model validation using in situ current speed, direction and sea elevation data confirmed the model's realistic representation of spatial and temporal aspects of circulation at the reef complex including a tidally driven current regime, eddies, and downwelling phenomena. This novel combination of 3D hydrodynamic modelling and remote sensing in deep-water ecosystems improves our understanding of the temporal and spatial scales of ecological processes occurring in marine systems. The modelled information has been integrated into a 3D GIS, providing a user interface for visualization and interrogation of results that allows wider ecological application of the model and that can provide valuable input for marine biodiversity and conservation applications. PMID:24873971

Comparative analysis of marine ecosystems: workshop on predator-prey interactions.

PubMed

Bailey, Kevin M; Ciannelli, Lorenzo; Hunsicker, Mary; Rindorf, Anna; Neuenfeldt, Stefan; Möllmann, Christian; Guichard, Frederic; Huse, Geir

2010-10-23

Climate and human influences on marine ecosystems are largely manifested by changes in predator-prey interactions. It follows that ecosystem-based management of the world's oceans requires a better understanding of food web relationships. An international workshop on predator-prey interactions in marine ecosystems was held at the Oregon State University, Corvallis, OR, USA on 16-18 March 2010. The meeting brought together scientists from diverse fields of expertise including theoretical ecology, animal behaviour, fish and seabird ecology, statistics, fisheries science and ecosystem modelling. The goals of the workshop were to critically examine the methods of scaling-up predator-prey interactions from local observations to systems, the role of shifting ecological processes with scale changes, and the complexity and organizational structure in trophic interactions.

The assessment of marine reserve networks: guidelines for ecological evaluation: Chapter 11

USGS Publications Warehouse

Grorud-Colvert, Kirsten; Claudet, Joachim; Carr, Mark; Caselle, Jennifer; Day, Jon; Friedlander, Alan M.; Lester, Sarah E.; Lison de Loma, Thierry; Tissot, Brian; Malone, Dan; Claudet, Joachim

2011-01-01

As marine ecosystems are plagued by an ever-increasing suite of threats including climate change, pollution, habitat degradation, and fisheries impacts (Roessig et al., 2004; Lotze et al., 2006; Jackson, 2008), there are now no ocean areas that are exempt from anthropogenic impacts (Halpern et al., 2008). In order to preserve marine biodiversity, ecosystem function, and the goods and services provided by resistant and/or resilient systems, marine reserves have been increasingly recommended as part of an ecosystem-based approach to management (Browman and Stergiou, 2004; Levin et al., 2009). Marine reserves are defined as “areas of the ocean completely protected from all extractive and destructive activities” (Lubchenco et al., 2003) and can be experimental controls for evaluating the impact of these activities on marine ecosystems. Growing scientific information has shown consistent increases in species density, biomass, size, and diversity in response to full protection inside reserves of varying sizes and ages located in diverse regions (Claudet et al., 2008; Lester et al., 2009; Molloy et al., 2009). However, most of these data are from individual marine reserves and therefore have inherently limited transferability to networks of marine reserves, which when properly designed can outperform single marine reserves for a variety of ecological, economic, and social management goals (Roberts et al., 2003; Almany et al., 2009; Gaines et al., 2010).The concept of marine reserve networks grew out of a desire to achieve both conservation and fishery management goals by minimizing the potential negative economic, social, and cultural impacts of a single large reserve while still producing similar or even greater ecological and economic returns (Murray et al., 1999; Gaines et al., 2010). In addition, reserves networks can provide insurance by protecting areas across a region and spreading the risk that these sites may be impacted by localized catastrophes such as hurricanes or oil spills (Allison et al., 2003). The World Conservation Union's Marine Programme defines a network as “a collection of individual marine protected areas (MPAs) or reserves operating co-operatively and synergistically, at various spatial scales and with a range of protection levels that are designed to meet objectives that a single reserve cannot achieve” (IUCN–WCPA, 2008). However, general terms such as “co-operatively” and “synergistically” can have myriad meanings. Without a clear definition of a network, it becomes difficult to identify attainable management goals and design a process for evaluating whether the network achieves those goals. Besides, different management goals may in turn result in the need for different types of networks. The use of MPAs with varying protection levels together with no-take zones in multiple-zoning schemes adds another layer of complexity to network design and evaluation; however, partially protected areas are generally used to manage coastal uses and avoid conflicts (rather than for strict ecological purposes) and are therefore a function of the local social, economic, and cultural context. As we are here interested in the ecological effects of networks, for the purposes of this chapter, we focus on marine reserves because these areas are no-take and therefore offer greater ecological benefits than other types of MPAs that allow some forms of extraction (Lester and Halpern, 2008).

Do reef fish habituate to diver presence? Evidence from two reef sites with contrasting historical levels of SCUBA intensity in the Bay Islands, Honduras.

PubMed

Titus, Benjamin M; Daly, Marymegan; Exton, Dan A

2015-01-01

Contact between humans and the marine environment is increasing, but the capacity of communities to adapt to human presence remains largely unknown. The popularization of SCUBA diving has added a new dimension to human impacts in aquatic systems and, although individual-level impacts have been identified, cumulative effects on ecosystem function and community-wide responses are unclear. In principle, habituation may mitigate the consequences of human presence on the biology of an individual and allow the quick resumption of its ecological roles, but this has not been documented in aquatic systems. Here, we investigate the short-term impact of human presence and the long-term habituation potential of reef-fish communities to recreational SCUBA divers by studying symbiotic cleaning interactions on coral reefs with differing levels of historical contact with divers. We show that incidences of human contact result in a smaller decline in ecosystem function and more rapid resumption of baseline services on a reef in Utila, Honduras that has heavy historical levels of SCUBA diver presence, compared to an un-dived reef site in the Cayos Cochinos Marine Protected Area (CCMPA). Nonetheless, despite the generally smaller change in ecosystem function and decades of regular contact with divers, cleaning behavior is suppressed by >50% at Utila when divers are present. We hypothesize that community-wide habituation of reef fish is not fully achievable and may be biologically restricted to only partial habituation. Differential responses to human presence impacts the interpretation and execution of behavioral research where SCUBA is the predominant means of data collection, and provides an important rationale for future research investigating the interplay between human presence, ecosystem function, and community structure on coral reefs.

TARGET ORGAN TOXICITY IN MARINE AND FRESHWATER TELEOSTS: VOLUME 1 - ORGANS

EPA Science Inventory

In any given aquatic ecosystem, fish serve a multitude of critical functions and so, are typically included in the risk assessment of various chemicals in waterways. However, uncertainties in toxicity evaluation can arise since these assessments are usually based solely on acute ...

TARGET ORGAN TOXICITY IN MARINE AND FRESHWATER TELEOSTS: VOLUME 2 - SYSTEMS

EPA Science Inventory

In any given aquatic ecosystem, fish serve a multitude of critical functions and so, are typically included in the risk assessment of various chemicals in waterways. However, uncertainties in toxicity evaluation can arise since these assessments are usually based solely on acute ...

Regional and inter-annual variability in Atlantic zooplankton en route to the Arctic Ocean: potential effects of multi-path Atlantic water advection through Fram Strait and the Barents Sea

NASA Astrophysics Data System (ADS)

Kwasniewski, Slawomir; Gluchowska, Marta; Trudnowska, Emilia; Ormanczyk, Mateusz; Walczowski, Waldemar; Beszczynska-Moeller, Agnieszka

2016-04-01

The Arctic is among the regions where the climate change effects on ecosystem will be the most rapid and consequential, with Arctic amplification recognized as an integral part of the process. Great part of the changes are forced by advection of warm waters from the North Atlantic and the expected modifications of Arctic marine ecosystem will be induced not only by changing environmental conditions but also as a result of introducing Atlantic biota. Thus, the knowledge of physical and biological heterogeneity of Atlantic inflow is requisite for understanding the effects of climate change on biological diversity and ecosystem functioning in the Arctic. The complex and variable two-branched structure of the Atlantic Water flow via Fram Strait and the Barents Sea most likely has a strong influence on the ocean biology in these regions, especially in the pelagic realm. Zooplankton are key components of marine ecosystems which form essential links between primary producers and grazer/predator consumers, thus they are important for functioning of the biological carbon pump. Changes in zooplankton distribution and abundance may have cascading effects on ecosystem functioning, with regulatory effects on climate. Based on data collected in summers of 2012-2014, within the scope of the Polish-Norwegian PAVE research project, we investigate zooplankton distribution, abundance and selected structural characteristics of communities, in relation to water mass properties in the Atlantic Water complex flow to the Arctic Ocean. The main questions addressed here are: what are the differences in zooplankton patterns between the Fram Strait and Barents Sea branches, and how does the inter-annual variability of Atlantic Water advection relate to changes in zooplankton? The results of the investigation are precondition for foreseeing changes in the pelagic realm in the Arctic Ocean and are necessary for constructing and tuning plankton components of ecosystem models.

Development of environmental impact monitoring protocol for offshore carbon capture and storage (CCS): A biological perspective

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Hyewon, E-mail: hyewon@ldeo.columbia.edu; Kim, Yong Hoon, E-mail: Yong.Kim@rpsgroup.com; Kang, Seong-Gil, E-mail: kangsg@kriso.re.kr

Offshore geologic storage of carbon dioxide (CO{sub 2}), known as offshore carbon capture and sequestration (CCS), has been under active investigation as a safe, effective mitigation option for reducing CO{sub 2} levels from anthropogenic fossil fuel burning and climate change. Along with increasing trends in implementation plans and related logistics on offshore CCS, thorough risk assessment (i.e. environmental impact monitoring) needs to be conducted to evaluate potential risks, such as CO{sub 2} gas leakage at injection sites. Gas leaks from offshore CCS may affect the physiology of marine organisms and disrupt certain ecosystem functions, thereby posing an environmental risk. Here,more » we synthesize current knowledge on environmental impact monitoring of offshore CCS with an emphasis on biological aspects and provide suggestions for better practice. Based on our critical review of preexisting literatures, this paper: 1) discusses key variables sensitive to or indicative of gas leakage by summarizing physico-chemical and ecological variables measured from previous monitoring cruises on offshore CCS; 2) lists ecosystem and organism responses to a similar environmental condition to CO{sub 2} leakage and associated impacts, such as ocean acidification and hypercapnia, to predict how they serve as responsive indicators of short- and long-term gas exposure, and 3) discusses the designs of the artificial gas release experiments in fields and the best model simulation to produce realistic leakage scenarios in marine ecosystems. Based on our analysis, we suggest that proper incorporation of biological aspects will provide successful and robust long-term monitoring strategies with earlier detection of gas leakage, thus reducing the risks associated with offshore CCS. - Highlights: • This paper synthesizes the current knowledge on environmental impact monitoring of offshore Carbon Capture and Sequestration (CCS). • Impacts of CO{sub 2} leakage (ocean acidification, hypercapnia) on marine organisms and ecosystems are discussed. • Insights and recommendations on EIA monitoring for CCS operations are proposed specifically in marine ecosystem perspective.« less

The elusive baseline of marine disease: Are diseases in ocean ecosystems increasing?

USGS Publications Warehouse

Ward, Jessica R.; Lafferty, Kevin D.

2004-01-01

Disease outbreaks alter the structure and function of marine ecosystems, directly affecting vertebrates (mammals, turtles, fish), invertebrates (corals, crustaceans, echinoderms), and plants (seagrasses). Previous studies suggest a recent increase in marine disease. However, lack of baseline data in most communities prevents a direct test of this hypothesis. We developed a proxy to evaluate a prediction of the increasing disease hypothesis: the proportion of scientific publications reporting disease increased in recent decades. This represents, to our knowledge, the first quantitative use of normalized trends in the literature to investigate an ecological hypothesis. We searched a literature database for reports of parasites and disease (hereafter “disease”) in nine marine taxonomic groups from 1970 to 2001. Reports, normalized for research effort, increased in turtles, corals, mammals, urchins, and molluscs. No significant trends were detected for seagrasses, decapods, or sharks/rays (though disease occurred in these groups). Counter to the prediction, disease reports decreased in fishes. Formulating effective resource management policy requires understanding the basis and timing of marine disease events. Why disease outbreaks increased in some groups but not in others should be a priority for future investigation. The increase in several groups lends urgency to understanding disease dynamics, particularly since few viable options currently exist to mitigate disease in the oceans.

A meta-analysis of zooplankton functional traits influencing ecosystem function.

PubMed

Hébert, Marie-Pier; Beisner, Beatrix E; Maranger, Roxane

2016-04-01

The use of functional traits to characterize community composition has been proposed as a more effective way to link community structure to ecosystem functioning. Organismal morphology, body stoichiometry, and physiology can be readily linked to large-scale ecosystem processes through functional traits that inform on interspecific and species-environment interactions; yet such effect traits are still poorly included in trait-based approaches. Given their key trophic position in aquatic ecosystems, individual zooplankton affect energy fluxes and elemental processing. We compiled a large database of zooplankton traits contributing to carbon, nitrogen, and phosphorus cycling and examined the effect of classification and habitat (marine vs. freshwater) on trait relationships. Respiration and nutrient excretion rates followed mass-dependent scaling in both habitats, with exponents ranging from 0.70 to 0.90. Our analyses revealed surprising differences in allometry and respiration between habitats, with freshwater species having lower length-specific mass and three times higher mass-specific respiration rates. These differences in traits point to implications for ecological strategies as well as overall carbon storage and fluxes based on habitat type. Our synthesis quantifies multiple trait relationships and links organisms to ecosystem processes they influence, enabling a more complete integration of aquatic community ecology and biogeochemistry through the promising use of effect traits.

Ecological consequences of invasion across the freshwater-marine transition in a warming world.

PubMed

Crespo, Daniel; Solan, Martin; Leston, Sara; Pardal, Miguel A; Dolbeth, Marina

2018-02-01

The freshwater-marine transition that characterizes an estuarine system can provide multiple entry options for invading species, yet the relative importance of this gradient in determining the functional contribution of invading species has received little attention. The ecological consequences of species invasion are routinely evaluated within a freshwater versus marine context, even though many invasive species can inhabit a wide range of salinities. We investigate the functional consequences of different sizes of Corbicula fluminea -an invasive species able to adapt to a wide range of temperatures and salinity-across the freshwater-marine transition in the presence versus absence of warming. Specifically, we characterize how C. fluminea affect fluid and particle transport, important processes in mediating nutrient cycling (NH 4 -N, NO 3 -N, PO 4 -P). Results showed that sediment particle reworking (bioturbation) tends to be influenced by size and to a lesser extent, temperature and salinity; nutrient concentrations are influenced by different interactions between all variables (salinity, temperature, and size class). Our findings demonstrate the highly context-dependent nature of the ecosystem consequences of invasion and highlight the potential for species to simultaneously occupy multiple components of an ecosystem. Recognizing of this aspect of invasibility is fundamental to management and conservation efforts, particularly as freshwater and marine systems tend to be compartmentalized rather than be treated as a contiguous unit. We conclude that more comprehensive appreciation of the distribution of invasive species across adjacent habitats and different seasons is urgently needed to allow the true extent of biological introductions, and their ecological consequences, to be fully realized.

Functionally diverse reef-fish communities ameliorate coral disease.

PubMed

Raymundo, Laurie J; Halford, Andrew R; Maypa, Aileen P; Kerr, Alexander M

2009-10-06

Coral reefs, the most diverse of marine ecosystems, currently experience unprecedented levels of degradation. Diseases are now recognized as a major cause of mortality in reef-forming corals and are complicit in phase shifts of reef ecosystems to algal-dominated states worldwide. Even so, factors contributing to disease occurrence, spread, and impact remain poorly understood. Ecosystem resilience has been linked to the conservation of functional diversity, whereas overfishing reduces functional diversity through cascading, top-down effects. Hence, we tested the hypothesis that reefs with trophically diverse reef fish communities have less coral disease than overfished reefs. We surveyed reefs across the central Philippines, including well-managed marine protected areas (MPAs), and found that disease prevalence was significantly negatively correlated with fish taxonomic diversity. Further, MPAs had significantly higher fish diversity and less disease than unprotected areas. We subsequently investigated potential links between coral disease and the trophic components of fish diversity, finding that only the density of coral-feeding chaetodontid butterflyfishes, seldom targeted by fishers, was positively associated with disease prevalence. These previously uncharacterized results are supported by a second large-scale dataset from the Great Barrier Reef. We hypothesize that members of the charismatic reef-fish family Chaetodontidae are major vectors of coral disease by virtue of their trophic specialization on hard corals and their ecological release in overfished areas, particularly outside MPAs.

Rapid emergence of climate change in environmental drivers of marine ecosystems.

PubMed

Henson, Stephanie A; Beaulieu, Claudie; Ilyina, Tatiana; John, Jasmin G; Long, Matthew; Séférian, Roland; Tjiputra, Jerry; Sarmiento, Jorge L

2017-03-07

Climate change is expected to modify ecological responses in the ocean, with the potential for important effects on the ecosystem services provided to humankind. Here we address the question of how rapidly multiple drivers of marine ecosystem change develop in the future ocean. By analysing an ensemble of models we find that, within the next 15 years, the climate change-driven trends in multiple ecosystem drivers emerge from the background of natural variability in 55% of the ocean and propagate rapidly to encompass 86% of the ocean by 2050 under a 'business-as-usual' scenario. However, we also demonstrate that the exposure of marine ecosystems to climate change-induced stress can be drastically reduced via climate mitigation measures; with mitigation, the proportion of ocean susceptible to multiple drivers within the next 15 years is reduced to 34%. Mitigation slows the pace at which multiple drivers emerge, allowing an additional 20 years for adaptation in marine ecological and socio-economic systems alike.

Identification, definition and quantification of goods and services provided by marine biodiversity: implications for the ecosystem approach.

PubMed

Beaumont, N J; Austen, M C; Atkins, J P; Burdon, D; Degraer, S; Dentinho, T P; Derous, S; Holm, P; Horton, T; van Ierland, E; Marboe, A H; Starkey, D J; Townsend, M; Zarzycki, T

2007-03-01

This paper identifies and defines ecosystem goods and services provided by marine biodiversity. Case studies have been used to provide an insight into the practical issues associated with the assessment of marine ecosystem goods and services at specific locations. The aim of this research was to validate the definitions of goods and services, and to identify knowledge gaps and likely difficulties of quantifying the goods and services. A validated theoretical framework for the assessment of goods and services is detailed, and examples of the goods and services at a variety of case study areas are documented. These results will enable future assessments of marine ecosystem goods and services. It is concluded that the utilisation of this goods and services approach has the capacity to play a fundamental role in the Ecosystem Approach, by enabling the pressures and demands of society, the economy and the environment to be integrated into environmental management.

Rapid emergence of climate change in environmental drivers of marine ecosystems

PubMed Central

Henson, Stephanie A.; Beaulieu, Claudie; Ilyina, Tatiana; John, Jasmin G.; Long, Matthew; Séférian, Roland; Tjiputra, Jerry; Sarmiento, Jorge L.

2017-01-01

Climate change is expected to modify ecological responses in the ocean, with the potential for important effects on the ecosystem services provided to humankind. Here we address the question of how rapidly multiple drivers of marine ecosystem change develop in the future ocean. By analysing an ensemble of models we find that, within the next 15 years, the climate change-driven trends in multiple ecosystem drivers emerge from the background of natural variability in 55% of the ocean and propagate rapidly to encompass 86% of the ocean by 2050 under a ‘business-as-usual' scenario. However, we also demonstrate that the exposure of marine ecosystems to climate change-induced stress can be drastically reduced via climate mitigation measures; with mitigation, the proportion of ocean susceptible to multiple drivers within the next 15 years is reduced to 34%. Mitigation slows the pace at which multiple drivers emerge, allowing an additional 20 years for adaptation in marine ecological and socio-economic systems alike. PMID:28267144

Characterising meso-marine ecosystems of the North Pacific

NASA Astrophysics Data System (ADS)

Batten, Sonia D.; David Hyrenbach, K.; Sydeman, William J.; Morgan, Ken H.; Henry, Michael F.; Yen, Peggy P. Y.; Welch, David W.

2006-02-01

To delineate mesoscale variability in marine ecosystems of the subarctic North Pacific and identify "hotspots" of biological activity, we conducted contemporaneous surveys of plankton and avifaunal communites in 2000-2003. Plankton samples were collected with a continuous plankton recorder (CPR) towed by a commercial vessel while a trained observer recorded marine bird distributions using strip-transect techniques. Near- and sub-surface physical oceanographic properties and productivity patterns were measured using a temperature data logger and satellite-derived chlorophyll a concentrations. We identified 10 distinct biological communities across the North Pacific, which we refer to as 'meso-marine ecosystems' (MME). We examined the characteristics of MME over multiple years to assess temporal persistence. MME were associated with different bathymetric domains and current systems. MME differed in the overall abundance and species composition of their fauna and, therefore, almost certainly in productivity. Regular monitoring of the spatial and temporal variability of MME will enhance our ability to detect and understand coupled climate-ecosystem responses, and, in turn, help guide ecosystem-based fisheries and wildlife management.

Rapid emergence of climate change in environmental drivers of marine ecosystems

NASA Astrophysics Data System (ADS)

Henson, Stephanie A.; Beaulieu, Claudie; Ilyina, Tatiana; John, Jasmin G.; Long, Matthew; Séférian, Roland; Tjiputra, Jerry; Sarmiento, Jorge L.

2017-03-01

Climate change is expected to modify ecological responses in the ocean, with the potential for important effects on the ecosystem services provided to humankind. Here we address the question of how rapidly multiple drivers of marine ecosystem change develop in the future ocean. By analysing an ensemble of models we find that, within the next 15 years, the climate change-driven trends in multiple ecosystem drivers emerge from the background of natural variability in 55% of the ocean and propagate rapidly to encompass 86% of the ocean by 2050 under a `business-as-usual' scenario. However, we also demonstrate that the exposure of marine ecosystems to climate change-induced stress can be drastically reduced via climate mitigation measures; with mitigation, the proportion of ocean susceptible to multiple drivers within the next 15 years is reduced to 34%. Mitigation slows the pace at which multiple drivers emerge, allowing an additional 20 years for adaptation in marine ecological and socio-economic systems alike.

Faunal communities and habitat characteristics of the Big Bend seagrass meadows, 2009-2010.

EPA Science Inventory

Seagrass meadows are important habitats that serve as nursery, feeding, and sheltering grounds for many marine species. In addition to the ecosystem functions and services they provide, seagrass habitats and associated fauna are commonly observed to have naturally high levels of...

Current Status and Future Prospects for the Assessment of Marine and Coastal Ecosystem Services: A Systematic Review

PubMed Central

Liquete, Camino; Piroddi, Chiara; Drakou, Evangelia G.; Gurney, Leigh; Katsanevakis, Stelios; Charef, Aymen; Egoh, Benis

2013-01-01

Background Research on ecosystem services has grown exponentially during the last decade. Most of the studies have focused on assessing and mapping terrestrial ecosystem services highlighting a knowledge gap on marine and coastal ecosystem services (MCES) and an urgent need to assess them. Methodology/Principal Findings We reviewed and summarized existing scientific literature related to MCES with the aim of extracting and classifying indicators used to assess and map them. We found 145 papers that specifically assessed marine and coastal ecosystem services from which we extracted 476 indicators. Food provision, in particular fisheries, was the most extensively analyzed MCES while water purification and coastal protection were the most frequently studied regulating and maintenance services. Also recreation and tourism under the cultural services was relatively well assessed. We highlight knowledge gaps regarding the availability of indicators that measure the capacity, flow or benefit derived from each ecosystem service. The majority of the case studies was found in mangroves and coastal wetlands and was mainly concentrated in Europe and North America. Our systematic review highlighted the need of an improved ecosystem service classification for marine and coastal systems, which is herein proposed with definitions and links to previous classifications. Conclusions/Significance This review summarizes the state of available information related to ecosystem services associated with marine and coastal ecosystems. The cataloging of MCES indicators and the integrated classification of MCES provided in this paper establish a background that can facilitate the planning and integration of future assessments. The final goal is to establish a consistent structure and populate it with information able to support the implementation of biodiversity conservation policies. PMID:23844080

Anthropogenic Litter in Urban Freshwater Ecosystems: Distribution and Microbial Interactions

PubMed Central

Hoellein, Timothy; Rojas, Miguel; Pink, Adam; Gasior, Joseph; Kelly, John

2014-01-01

Accumulation of anthropogenic litter (i.e. garbage; AL) and its ecosystem effects in marine environments are well documented. Rivers receive AL from terrestrial habitats and represent a major source of AL to marine environments, but AL is rarely studied within freshwater ecosystems. Our objectives were to 1) quantify AL density in urban freshwaters, 2) compare AL abundance among freshwater, terrestrial, and marine ecosystems, and 3) characterize the activity and composition of AL biofilms in freshwater habitats. We quantified AL from the Chicago River and Chicago's Lake Michigan shoreline, and found that AL abundance in Chicago freshwater ecosystems was comparable to previously reported data for marine and terrestrial ecosystems, although AL density and composition differed among habitats. To assess microbial interactions with AL, we incubated AL and natural substrates in 3 freshwater ecosystems, quantified biofilm metabolism as gross primary production (GPP) and community respiration (CR), and characterized biofilm bacterial community composition via high-throughput sequencing of 16S rRNA genes. The main driver of biofilm community composition was incubation location (e.g., river vs pond), but there were some significant differences in biofilm composition and metabolism among substrates. For example, biofilms on organic substrates (cardboard and leaves) had lower GPP than hard substrates (glass, plastic, aluminum and tiles). In addition, bacterial communities on organic substrates were distinct in composition from those on hard substrates, with higher relative abundances of bacteria associated with cellulose decomposition. Finally, we used our results to develop a conceptual diagram designed to unite the study of AL in terrestrial and freshwater environments with the well-established field of marine debris research. We suggest this broad perspective will be useful for future studies which synthesize AL sources, ecosystem effects, and fate across multiple ecosystem types, and will benefit management and reduction of global AL accumulations. PMID:24955768

Anthropogenic litter in urban freshwater ecosystems: distribution and microbial interactions.

PubMed

Hoellein, Timothy; Rojas, Miguel; Pink, Adam; Gasior, Joseph; Kelly, John

2014-01-01

Accumulation of anthropogenic litter (i.e. garbage; AL) and its ecosystem effects in marine environments are well documented. Rivers receive AL from terrestrial habitats and represent a major source of AL to marine environments, but AL is rarely studied within freshwater ecosystems. Our objectives were to 1) quantify AL density in urban freshwaters, 2) compare AL abundance among freshwater, terrestrial, and marine ecosystems, and 3) characterize the activity and composition of AL biofilms in freshwater habitats. We quantified AL from the Chicago River and Chicago's Lake Michigan shoreline, and found that AL abundance in Chicago freshwater ecosystems was comparable to previously reported data for marine and terrestrial ecosystems, although AL density and composition differed among habitats. To assess microbial interactions with AL, we incubated AL and natural substrates in 3 freshwater ecosystems, quantified biofilm metabolism as gross primary production (GPP) and community respiration (CR), and characterized biofilm bacterial community composition via high-throughput sequencing of 16S rRNA genes. The main driver of biofilm community composition was incubation location (e.g., river vs pond), but there were some significant differences in biofilm composition and metabolism among substrates. For example, biofilms on organic substrates (cardboard and leaves) had lower GPP than hard substrates (glass, plastic, aluminum and tiles). In addition, bacterial communities on organic substrates were distinct in composition from those on hard substrates, with higher relative abundances of bacteria associated with cellulose decomposition. Finally, we used our results to develop a conceptual diagram designed to unite the study of AL in terrestrial and freshwater environments with the well-established field of marine debris research. We suggest this broad perspective will be useful for future studies which synthesize AL sources, ecosystem effects, and fate across multiple ecosystem types, and will benefit management and reduction of global AL accumulations.

Ecosystem Pen Pals: Using Place-Based Marine Science and Culture to Connect Students

ERIC Educational Resources Information Center

Wiener, Carlie S.; Matsumoto, Karen

2014-01-01

The marine environment provides a unique context for students to explore both natural and cultural connections. This paper reports preliminary findings on Ecosystem Pen Pals, an ocean literacy program for 4th and 5th graders focused on using a pen pal model for integrating traditional ecological knowledge into marine science. Surveys with…

Predicting Trophic Interactions and Habitat Utilization in the California Current Ecosystem

DTIC Science & Technology

2013-09-30

in the California Current Ecosystem Jerome Fiechter UC Santa Cruz Institute of Marine Sciences 1156 High Street Santa Cruz, CA 95064 phone... Ecosystem (CCLME), the long-term goal of our modeling approach is to better understand and characterize biological “hotspots” (i.e., the aggregation of...multiple marine organisms over multiple trophic levels) off the U.S. west coast and in other regions where similar fully-coupled ecosystem models may

The ups and downs of trophic control in continental shelf ecosystems.

PubMed

Frank, Kenneth T; Petrie, Brian; Shackell, Nancy L

2007-05-01

Traditionally, marine ecosystem structure was thought to be determined by phytoplankton dynamics. However, an integrated view on the relative roles of top-down (consumer-driven) and bottom-up (resource-driven) forcing in large-scale, exploited marine ecosystems is emerging. Long time series of scientific survey data, underpinning the management of commercially exploited species such as cod, are being used to diagnose mechanisms that could affect the composition and relative abundance of species in marine food webs. By assembling published data from studies in exploited North Atlantic ecosystems, we found pronounced geographical variation in top-down and bottom-up trophic forcing. The data suggest that ecosystem susceptibility to top-down control and their resiliency to exploitation are related to species richness and oceanic temperature conditions. Such knowledge could be used to produce ecosystem guidelines to regulate and manage fisheries in a sustainable fashion.

Differential tolerances to ocean acidification by parasites that share the same host.

PubMed

MacLeod, C D; Poulin, R

2015-06-01

Ocean acidification is predicted to cause major changes in marine ecosystem structure and function over the next century, as species-specific tolerances to acidified seawater may alter previously stable relationships between coexisting organisms. Such differential tolerances could affect marine host-parasite associations, as either host or parasite may prove more susceptible to the stressors associated with ocean acidification. Despite their important role in many ecological processes, parasites have not been studied in the context of ocean acidification. We tested the effects of low pH seawater on the cercariae and, where possible, the metacercariae of four species of marine trematode parasite. Acidified seawater (pH 7.6 and 7.4, 12.5 °C) caused a 40-60% reduction in cercarial longevity and a 0-78% reduction in metacercarial survival. However, the reduction in longevity and survival varied distinctly between parasite taxa, indicating that the effects of reduced pH may be species-specific. These results suggest that ocean acidification has the potential to reduce the transmission success of many trematode species, decrease parasite abundance and alter the fundamental regulatory role of multi-host parasites in marine ecosystems. Copyright © 2015 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

Cryptic diversity and ecosystem functioning: a complex tale of differential effects on decomposition.

PubMed

De Meester, N; Gingold, R; Rigaux, A; Derycke, S; Moens, T

2016-10-01

Marine ecosystems are experiencing accelerating population and species loss. Some ecosystem functions are decreasing and there is growing interest in the link between biodiversity and ecosystem functioning. The role of cryptic (morphologically identical but genetically distinct) species in this biodiversity-ecosystem functioning link is unclear and has not yet been formally tested. We tested if there is a differential effect of four cryptic species of the bacterivorous nematode Litoditis marina on the decomposition process of macroalgae. Bacterivorous nematodes can stimulate or slow down bacterial activity and modify the bacterial assemblage composition. Moreover, we tested if interspecific interactions among the four cryptic species influence the decomposition process. A laboratory experiment with both mono- and multispecific nematode cultures was conducted, and loss of organic matter and the activity of two key extracellular enzymes for the degradation of phytodetritus were assessed. L. marina mainly influenced qualitative aspects of the decomposition process rather than its overall rate: an effect of the nematodes on the enzymatic activities became manifest, although no clear nematode effect on bulk organic matter weight loss was found. We also demonstrated that species-specific effects on the decomposition process existed. Combining the four cryptic species resulted in high competition, with one dominant species, but without complete exclusion of other species. These interspecific interactions translated into different effects on the decomposition process. The species-specific differences indicated that each cryptic species may play an important and distinct role in ecosystem functioning. Functional differences may result in coexistence among very similar species.

Marine metagenomics: strategies for the discovery of novel enzymes with biotechnological applications from marine environments

PubMed Central

Kennedy, Jonathan; Marchesi, Julian R; Dobson, Alan DW

2008-01-01

Metagenomic based strategies have previously been successfully employed as powerful tools to isolate and identify enzymes with novel biocatalytic activities from the unculturable component of microbial communities from various terrestrial environmental niches. Both sequence based and function based screening approaches have been employed to identify genes encoding novel biocatalytic activities and metabolic pathways from metagenomic libraries. While much of the focus to date has centred on terrestrial based microbial ecosystems, it is clear that the marine environment has enormous microbial biodiversity that remains largely unstudied. Marine microbes are both extremely abundant and diverse; the environments they occupy likewise consist of very diverse niches. As culture-dependent methods have thus far resulted in the isolation of only a tiny percentage of the marine microbiota the application of metagenomic strategies holds great potential to study and exploit the enormous microbial biodiversity which is present within these marine environments. PMID:18717988

Heterotrophic Archaea dominate sedimentary subsurface ecosystems off Peru

PubMed Central

Biddle, Jennifer F.; Lipp, Julius S.; Lever, Mark A.; Lloyd, Karen G.; Sørensen, Ketil B.; Anderson, Rika; Fredricks, Helen F.; Elvert, Marcus; Kelly, Timothy J.; Schrag, Daniel P.; Sogin, Mitchell L.; Brenchley, Jean E.; Teske, Andreas; House, Christopher H.; Hinrichs, Kai-Uwe

2006-01-01

Studies of deeply buried, sedimentary microbial communities and associated biogeochemical processes during Ocean Drilling Program Leg 201 showed elevated prokaryotic cell numbers in sediment layers where methane is consumed anaerobically at the expense of sulfate. Here, we show that extractable archaeal rRNA, selecting only for active community members in these ecosystems, is dominated by sequences of uncultivated Archaea affiliated with the Marine Benthic Group B and the Miscellaneous Crenarchaeotal Group, whereas known methanotrophic Archaea are not detectable. Carbon flow reconstructions based on stable isotopic compositions of whole archaeal cells, intact archaeal membrane lipids, and other sedimentary carbon pools indicate that these Archaea assimilate sedimentary organic compounds other than methane even though methanotrophy accounts for a major fraction of carbon cycled in these ecosystems. Oxidation of methane by members of Marine Benthic Group B and the Miscellaneous Crenarchaeotal Group without assimilation of methane–carbon provides a plausible explanation. Maintenance energies of these subsurface communities appear to be orders of magnitude lower than minimum values known from laboratory observations, and ecosystem-level carbon budgets suggest that community turnover times are on the order of 100–2,000 years. Our study provides clues about the metabolic functionality of two cosmopolitan groups of uncultured Archaea. PMID:16505362

Marine Biogeochemistry Under The Influence of Fish And Fisheries: An Ecosystem Modeling Study

NASA Astrophysics Data System (ADS)

Disa, Deniz; Akoglu, Ekin; Salihoglu, Baris

2017-04-01

The ocean and the marine ecosystems are important controllers of the global carbon cycle. They play a pivotal role in capturing atmospheric carbon into the ocean body, transforming it into organic carbon through photosynthesis and transporting it to the depths of the ocean. Fish, which has a significant role in the marine food webs, is thought to have a considerable impact on carbon export. More specifically, fish has a control on plankton dynamics as a predator, it provides nutrient to the ecosystem by its metabolic activities and it has the ability of moving actively and transporting materials. Fishing is also expected to impact carbon cycle because it directly changes the fish biomasses. However, how fish impacts the biogeochemistry of marine ecosystems is not studied extensively. The aim of this study is to analyze the impact of fish and fisheries on marine biogeochemical processes by setting up an end-to-end model, which simulates lower and higher tropic levels of marine ecosystems simultaneously. For this purpose, a one dimensional biogeochemical model simulating lower tropic level dynamics (e.g. carbon export, nutrient cycles) and an food web model simulating fisheries exploitation and higher tropic level dynamics were online and two-way coupled. Representing the marine ecosystem from one end to the other, the coupled model served as a tool for the analysis of fishing impacts on marine biogeochemical dynamics. Results obtained after incorporation of higher trophic level model changed the plankton compositions and enhanced detritus pools and increased carbon export. Additionally, our model showed that active movement of fish contributed to transport of carbon from surface to the deeper parts of the ocean. Moreover, results after applying different fishing intensities indicated that changes in fisheries exploitation levels directly influence the marine nutrient cycles and hence, the carbon export. Depending on the target and the intensity of fisheries, considerable changes in the biogeochemical responses observed. In conclusion, unlike the models that do not represent the fish explicitly, we demonstrate how marine biogeochemical processes are impacted by the activity of fish assemblages and fisheries exploitation.

An integrated approach to manage coastal ecosystems and prevent marine pollution effects

NASA Astrophysics Data System (ADS)

Marcelli, Marco; Bonamano, Simone; Carli, Filippo Maria; Giovacchini, Monica; Madonia, Alice; Mancini, Emanuele; Molino, Chiara; Piermattei, Viviana; Manfredi Frattarelli, Francesco

2016-04-01

This work focuses an integrated approach based on Sea-Use-Map (SUM), backed by a permanent monitoring system (C-CEMS-Civitavecchia Coastal Environmental Monitoring System). This tool supports the management of the marine coastal area, contributing substantially to ecosystem benefits evaluation and to minimize pollution impacts. Within the Blue Growth strategy, the protection of marine ecosystems is considered a priority for the sustainable growth of marine and maritime sectors. To face this issue, the European MSP and MSFD directives (2014/89/EU; 2008/56/EC) strongly promote the adoption of an ecosystem-based approach, paying particular attention to the support of monitoring networks that use L-TER (long-term ecological research) observations and integrate multi-disciplinary data sets. Although not largely used in Europe yet, the Environmental Sensitivity Index (ESI), developed in 1979 by NOAA (and promoted by IMO in 2010), can be considered an excellent example of ecosystem-based approach to reduce the environmental consequences of an oil spill event in a coastal area. SUM is an ecosystem oriented cartographic tool specifically designed to support the sustainable management of the coastal areas, such as the selection of the best sites for the introduction of new uses or the identification of the coastal areas subjected to potential impacts. It also enables a rapid evaluation of the benefits produced by marine areas as well as of their anthropogenic disturbance. SUM integrates C-CEMS dataset, geomorphological and ecological features and knowledge on the coastal and maritime space uses. The SUM appliance allowed to obtain relevant operational results in the Civitavecchia coastal area (Latium, Italy), characterized by high variability of marine and coastal environments, historical heritage and affected by the presence of a big harbour, relevant industrial infrastructures, and touristic features. In particular, the valuation of marine ecosystem services based on benthic biocenosis as relevant spatial unit, and the ESI calculation for Civitavecchia coastal areas, are reported.

Let's go beyond taxonomy in diet description: testing a trait-based approach to prey-predator relationships.

PubMed

Spitz, Jérôme; Ridoux, Vincent; Brind'Amour, Anik

2014-09-01

Understanding 'Why a prey is a prey for a given predator?' can be facilitated through trait-based approaches that identify linkages between prey and predator morphological and ecological characteristics and highlight key functions involved in prey selection. Enhanced understanding of the functional relationships between predators and their prey is now essential to go beyond the traditional taxonomic framework of dietary studies and to improve our knowledge of ecosystem functioning for wildlife conservation and management. We test the relevance of a three-matrix approach in foraging ecology among a marine mammal community in the northeast Atlantic to identify the key functional traits shaping prey selection processes regardless of the taxonomy of both the predators and prey. Our study reveals that prey found in the diet of marine mammals possess functional traits which are directly and significantly linked to predator characteristics, allowing the establishment of a functional typology of marine mammal-prey relationships. We found prey selection of marine mammals was primarily shaped by physiological and morphological traits of both predators and prey, confirming that energetic costs of foraging strategies and muscular performance are major drivers of prey selection in marine mammals. We demonstrate that trait-based approaches can provide a new definition of the resource needs of predators. This framework can be used to anticipate bottom-up effects on marine predator population dynamics and to identify predators which are sensitive to the loss of key prey functional traits when prey availability is reduced. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

Climate change and body size shift in Mediterranean bivalve assemblages: unexpected role of biological invasions.

PubMed

Nawrot, Rafał; Albano, Paolo G; Chattopadhyay, Devapriya; Zuschin, Martin

2017-08-16

Body size is a synthetic functional trait determining many key ecosystem properties. Reduction in average body size has been suggested as one of the universal responses to global warming in aquatic ecosystems. Climate change, however, coincides with human-enhanced dispersal of alien species and can facilitate their establishment. We address effects of species introductions on the size structure of recipient communities using data on Red Sea bivalves entering the Mediterranean Sea through the Suez Canal. We show that the invasion leads to increase in median body size of the Mediterranean assemblage. Alien species are significantly larger than native Mediterranean bivalves, even though they represent a random subset of the Red Sea species with respect to body size. The observed patterns result primarily from the differences in the taxonomic composition and body-size distributions of the source and recipient species pools. In contrast to the expectations based on the general temperature-size relationships in marine ectotherms, continued warming of the Mediterranean Sea indirectly leads to an increase in the proportion of large-bodied species in bivalve assemblages by accelerating the entry and spread of tropical aliens. These results underscore complex interactions between changing climate and species invasions in driving functional shifts in marine ecosystems. © 2017 The Author(s).

Investigation of XoxF methanol dehydrogenases reveals new methylotrophic bacteria in pelagic marine and freshwater ecosystems.

PubMed

Ramachandran, Arthi; Walsh, David A

2015-10-01

The diversity and distribution of methylotrophic bacteria have been investigated in the oceans and lakes using the methanol dehydrogenase mxaF gene as a functional marker. However, pelagic marine (OM43) and freshwater (LD28 and PRD01a001B) methylotrophs within the Betaproteobacteria lack mxaF, instead possessing a related xoxF4-encoded methanol dehydrogenase. Here, we developed and employed xoxF4 as a complementary functional gene marker to mxaF for studying methylotrophs in aquatic environment. Using xoxF4, we detected OM43-related and LD28-related methylotrophs in the ocean and freshwaters of North America, respectively, and showed the coexistence of these two lineages in a large estuarine system (St Lawrence Estuary). Gene expression patterns of xoxF4 supported a positive relationship between xoxF4-containing methylotroph activity and spring time productivity, suggesting phytoplankton blooms are a source of methylotrophic substrates. Further investigation of methanol dehydrogenase diversity in pelagic ecosystems using comparative metagenomics provided strong support for a widespread distribution of xoxF4 (as well as several distinct xoxF5) containing methylotrophs in marine and freshwater surface waters. In total, these results demonstrate a geographical distribution of OM43/LD28-related methylotrophs that includes marine and freshwaters and suggest that methylotrophy occurring in the water column is an important component of lake and estuary carbon cycling and biogeochemistry. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Ecosystem-Based Management and the Sustainable Delivery of Marine Ecosystem Services

NASA Astrophysics Data System (ADS)

Fogarty, M.; Schwing, F. B.

2016-12-01

Ecosystem-Based Management can provide an essential framework for the sustainable delivery of a broad spectrum of marine Ecosystem Services (ES) essential to human well being. Key elements of the approach involve the specification of clearly articulated goals for EBM; the development of an accompanying Marine Ecosystem Services Assessment (MESA) designed to evaluate the status of delivery of these services; and strategies for the implementation of management options designed to achieve the stated goals of the program. The specification of goals is the purview of managers. In the United States under the provisions of the National Ocean Policy, Regional Planning Bodies are charged with the responsibility of articulating goals and developing strategies to meet these goals. Government agencies, in concert with the broader scientific community, hold the responsibility for assessing the status of the delivery of ecosystem services in relation to designated objectives and advising on appropriate management strategies. In this presentation, I will illustrate the specification of a MESA for the Northwest U.S Continental Shelf Large Marine Ecosystem (NES LME). The approach focuses on the evaluation of ES indicators and additional metrics related to threats and impacts to the sustainable delivery of these services. Results are combined into an overall index of status of the NES LME.

Microfungi diversity isolation from sandy soil of Acapulco touristic beaches

USDA-ARS?s Scientific Manuscript database

Microscopic fungi diversity in marine sandy soil habitats is associated with key functions of beach ecosystems. There are few reports on their presence in Mexican beaches. Although standard methods to obtain the fungi from soil samples are established, the aim of this pilot study was to test the pla...

Valuing Blue Carbon: Carbon Sequestration Benefits Provided by the Marine Protected Areas in Colombia

PubMed Central

2015-01-01

Marine protected areas are aimed to protect and conserve key ecosystems for the provision of a number of ecosystem services that are the basis for numerous economic activities. Among the several services that these areas provide, the capacity of sequestering (capturing and storing) organic carbon is a regulating service, provided mainly by mangroves and seagrasses, that gains importance as alternatives for mitigating global warming become a priority in the international agenda. The objective of this study is to value the services associated with the capture and storage of oceanic carbon, known as Blue Carbon, provided by a new network of marine protected areas in Colombia. We approach the monetary value associated to these services through the simulation of a hypothetical market for oceanic carbon. To do that, we construct a benefit function that considers the capacity of mangroves and seagrasses for capturing and storing blue carbon, and simulate scenarios for the variation of key variables such as the market carbon price, the discount rate, the natural rate of loss of the ecosystems, and the expectations about the post-Kyoto negotiations. The results indicate that the expected benefits associated to carbon capture and storage provided by these ecosystems are substantial but highly dependent on the expectations in terms of the negotiations surrounding the extension of the Kyoto Protocol and the dynamics of the carbon credit’s demand and supply. We also find that the natural loss rate of these ecosystems does not seem to have a significant effect on the annual value of the benefits. This approach constitutes one of the first attempts to value blue carbon as one of the services provided by conservation. PMID:26018814

Climate change effects on the Baltic Sea borderland between land and sea.

PubMed

Strandmark, Alma; Bring, Arvid; Cousins, Sara A O; Destouni, Georgia; Kautsky, Hans; Kolb, Gundula; de la Torre-Castro, Maricela; Hambäck, Peter A

2015-01-01

Coastal habitats are situated on the border between land and sea, and ecosystem structure and functioning is influenced by both marine and terrestrial processes. Despite this, most scientific studies and monitoring are conducted either with a terrestrial or an aquatic focus. To address issues concerning climate change impacts in coastal areas, a cross-ecosystem approach is necessary. Since habitats along the Baltic coastlines vary in hydrology, natural geography, and ecology, climate change projections for Baltic shore ecosystems are bound to be highly speculative. Societal responses to climate change in the Baltic coastal ecosystems should have an ecosystem approach and match the biophysical realities of the Baltic Sea area. Knowledge about ecosystem processes and their responses to a changing climate should be integrated within the decision process, both locally and nationally, in order to increase the awareness of, and to prepare for climate change impacts in coastal areas of the Baltic Sea.

Climate change and adaptational impacts in coastal systems: the case of sea defences.

PubMed

Firth, Louise B; Mieszkowska, Nova; Thompson, Richard C; Hawkins, Stephen J

2013-09-01

We briefly review how coastal ecosystems are responding to and being impacted by climate change, one of the greatest challenges facing society today. In adapting to rising and stormier seas associated with climate change, coastal defence structures are proliferating and becoming dominant coastal features, particularly in urbanised areas. Whilst the primary function of these structures is to protect coastal property and infrastructure, they inevitably have a significant secondary impact on the local environment and ecosystems. In this review we outline some of the negative and positive effects of these structures on physical processes, impacts on marine species, and the novel engineering approaches that have been employed to improve the ecological value of these structures in recent years. Finally we outline guidelines for an environmentally sensitive approach to design of such structures in the marine environment.

Marine biodiversity–ecosystem functions under uncertain environmental futures

PubMed Central

Bulling, Mark T.; Hicks, Natalie; Murray, Leigh; Paterson, David M.; Raffaelli, Dave; White, Piran C. L.; Solan, Martin

2010-01-01

Anthropogenic activity is currently leading to dramatic transformations of ecosystems and losses of biodiversity. The recognition that these ecosystems provide services that are essential for human well-being has led to a major interest in the forms of the biodiversity–ecosystem functioning relationship. However, there is a lack of studies examining the impact of climate change on these relationships and it remains unclear how multiple climatic drivers may affect levels of ecosystem functioning. Here, we examine the roles of two important climate change variables, temperature and concentration of atmospheric carbon dioxide, on the relationship between invertebrate species richness and nutrient release in a model benthic estuarine system. We found a positive relationship between invertebrate species richness and the levels of release of NH4-N into the water column, but no effect of species richness on the release of PO4-P. Higher temperatures and greater concentrations of atmospheric carbon dioxide had a negative impact on nutrient release. Importantly, we found significant interactions between the climate variables, indicating that reliably predicting the effects of future climate change will not be straightforward as multiple drivers are unlikely to have purely additive effects, resulting in increased levels of uncertainty. PMID:20513718

Marine biodiversity-ecosystem functions under uncertain environmental futures.

PubMed

Bulling, Mark T; Hicks, Natalie; Murray, Leigh; Paterson, David M; Raffaelli, Dave; White, Piran C L; Solan, Martin

2010-07-12

Anthropogenic activity is currently leading to dramatic transformations of ecosystems and losses of biodiversity. The recognition that these ecosystems provide services that are essential for human well-being has led to a major interest in the forms of the biodiversity-ecosystem functioning relationship. However, there is a lack of studies examining the impact of climate change on these relationships and it remains unclear how multiple climatic drivers may affect levels of ecosystem functioning. Here, we examine the roles of two important climate change variables, temperature and concentration of atmospheric carbon dioxide, on the relationship between invertebrate species richness and nutrient release in a model benthic estuarine system. We found a positive relationship between invertebrate species richness and the levels of release of NH(4)-N into the water column, but no effect of species richness on the release of PO(4)-P. Higher temperatures and greater concentrations of atmospheric carbon dioxide had a negative impact on nutrient release. Importantly, we found significant interactions between the climate variables, indicating that reliably predicting the effects of future climate change will not be straightforward as multiple drivers are unlikely to have purely additive effects, resulting in increased levels of uncertainty.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ruvindy, Rendy; White III, Richard Allen; Neilan, Brett Anthony

Modern microbial mats are potential analogues of some of Earth’s earliest ecosystems. Excellent examples can be found in Shark Bay, Australia, with mats of various morphologies. To further our understanding of the functional genetic potential of these complex microbial ecosystems, we conducted for the first time shotgun metagenomic analyses. We assembled metagenomic nextgeneration sequencing data to classify the taxonomic and metabolic potential across diverse morphologies of marine mats in Shark Bay. The microbial community across taxonomic classifications using protein-coding and small subunit rRNA genes directly extracted from the metagenomes suggests that three phyla Proteobacteria, Cyanobacteria and Bacteriodetes dominate all marinemore » mats. However, the microbial community structure between Shark Bay and Highbourne Cay (Bahamas) marine systems appears to be distinct from each other. The metabolic potential (based on SEED subsystem classifications) of the Shark Bay and Highbourne Cay microbial communities were also distinct. Shark Bay metagenomes have a metabolic pathway profile consisting of both heterotrophic and photosynthetic pathways, whereas Highbourne Cay appears to be dominated almost exclusively by photosynthetic pathways. Alternative non-rubisco-based carbon metabolism including reductive TCA cycle and 3-hydroxypropionate/4-hydroxybutyrate pathways is highly represented in Shark Bay metagenomes while not represented in Highbourne Cay microbial mats or any other mat forming ecosystems investigated to date. Potentially novel aspects of nitrogen cycling were also observed, as well as putative heavy metal cycling (arsenic, mercury, copper and cadmium). Finally, archaea are highly represented in Shark Bay and may have critical roles in overall ecosystem function in these modern microbial mats.« less

Community dynamics and ecosystem simplification in a high-CO2 ocean.

PubMed

Kroeker, Kristy J; Gambi, Maria Cristina; Micheli, Fiorenza

2013-07-30

Disturbances are natural features of ecosystems that promote variability in the community and ultimately maintain diversity. Although it is recognized that global change will affect environmental disturbance regimes, our understanding of the community dynamics governing ecosystem recovery and the maintenance of functional diversity in future scenarios is very limited. Here, we use one of the few ecosystems naturally exposed to future scenarios of environmental change to examine disturbance and recovery dynamics. We examine the recovery patterns of marine species from a physical disturbance across different acidification regimes caused by volcanic CO2 vents. Plots of shallow rocky reef were cleared of all species in areas of ambient, low, and extreme low pH that correspond to near-future and extreme scenarios for ocean acidification. Our results illustrate how acidification decreases the variability of communities, resulting in homogenization and reduced functional diversity at a landscape scale. Whereas the recovery trajectories in ambient pH were highly variable and resulted in a diverse range of assemblages, recovery was more predictable with acidification and consistently resulted in very similar algal-dominated assemblages. Furthermore, low pH zones had fewer signs of biological disturbance (primarily sea urchin grazing) and increased recovery rates of the dominant taxa (primarily fleshy algae). Together, our results highlight how environmental change can cause ecosystem simplification via environmentally mediated changes in community dynamics in the near future, with cascading impacts on functional diversity and ecosystem function.

Integrating the provision of ecosystem services and trawl fisheries for the management of the marine environment.

PubMed

Muntadas, Alba; de Juan, Silvia; Demestre, Montserrat

2015-02-15

The species interaction and their biological traits (BT) determine the function of benthic communities and, hence, the delivery of ecosystem services. Therefore, disturbance of benthic communities by trawling may compromise ecosystem service delivery, including fisheries' catches. In this work, we explore 1) the impact of trawling activities on benthic functional components (after the BTA approach) and 2) how trawling impact may affect the ecosystem services delivered by benthic communities. To this aim, we assessed the provision of ecosystem services by adopting the concept of Ecosystem Service Providers (ESP), i.e. ecological units that perform ecosystem functions that will ultimately deliver ecosystem services. We studied thirteen sites subjected to different levels of fishing effort in the Mediterranean. From a range of environmental variables included in the study, we found ESPs to be mainly affected by fishing effort and grain size. Our results suggested that habitat type has significant effects on the distribution of ESPs and this natural variability influences ESP response to trawling at a specific site. In order to summarize the complex relationships between human uses, ecosystem components and the demand for ecosystem services in trawling grounds, we adapted a DPSIR (Drivers-Pressures-State Change-Impact-Response) framework to the study area, emphasizing the role of society as Drivers of change and actors demanding management Responses. This integrative framework aims to inform managers about the interactions between all the elements involved in the management of trawling grounds, highlighting the need for an integrated approach in order to ensure ecosystem service provision. Copyright © 2014 Elsevier B.V. All rights reserved.

Draft Genome Sequences of Gammaproteobacterial Methanotrophs Isolated from Marine Ecosystems: TABLE 1 

DOE PAGES

Flynn, James D.; Hirayama, Hisako; Sakai, Yasuyoshi; ...

2016-01-21

The genome sequences ofMethylobacter marinusA45,Methylobactersp. strain BBA5.1, andMethylomarinum vadiIT-4 were obtained. These aerobic methanotrophs are typical members of coastal and hydrothermal vent marine ecosystems.

Marine Research Infrastructure collaboration in the COOPLUS project framework - Promoting synergies for marine ecosystems studies

NASA Astrophysics Data System (ADS)

Beranzoli, L.; Best, M.; Embriaco, D.; Favali, P.; Juniper, K.; Lo Bue, N.; Lara-Lopez, A.; Materia, P.; Ó Conchubhair, D.; O'Rourke, E.; Proctor, R.; Weller, R. A.

2017-12-01

Understanding effects on marine ecosystems of multiple drivers at various scales; from regional such as climate and ocean circulation, to local, such as seafloor gas emissions and harmful underwater noise, requires long time-series of integrated and standardised datasets. Large-scale research infrastructures for ocean observation are able to provide such time-series for a variety of ocean process physical parameters (mass and energy exchanges among surface, water column and benthic boundary layer) that constitute important and necessary measures of environmental conditions and change/development over time. Information deduced from these data is essential for the study, modelling and prediction of marine ecosystems changes and can reveal and potentially confirm deterioration and threats. The COOPLUS European Commission project brings together research infrastructures with the aim of coordinating multilateral cooperation among RIs and identifying common priorities, actions, instruments, resources. COOPLUS will produce a Strategic Research and Innovation Agenda (SRIA) which will be a shared roadmap for mid to long-term collaboration. In particular, marine RIs collaborating in COOPLUS, namely the European Multidisciplinary Seafloor and water column Observatory: EMSO (Europe), the Ocean Observatories Initiative (OOI, USA), Ocean Networks Canada (ONC), and the Integrated Marine Observing System (IMOS, Australia), can represent a source of important data for researchers of marine ecosystems. The RIs can then, in turn, receive suggestions from researchers for implementing new measurements and stimulating cross-cutting collaborations and data integration and standardisation from their user community. This poster provides a description of EMSO, OOI, ONC and IMOS for the benefit of marine ecosystem studies and presents examples of where the analyses of time-series have revealed noteworthy environmental conditions, temporal trends and events.

Isotope and fatty acid trends along continental shelf depth gradients: Inshore versus offshore hydrological influences on benthic trophic functioning

NASA Astrophysics Data System (ADS)

Chouvelon, T.; Schaal, G.; Grall, J.; Pernet, F.; Perdriau, M.; A-Pernet, E. J.; Le Bris, H.

2015-11-01

Anthropogenic activities and land-based inputs into the sea may influence the trophic structure and functioning of coastal and continental shelf ecosystems, despite the numerous opportunities and services the latter offer to humans and wildlife. In addition, hydrological structures and physical dynamics potentially influence the sources of organic matter (e.g., terrestrial versus marine, or fresh material versus detrital material) entering marine food webs. Understanding the significance of the processes that influence marine food webs and ecosystems (e.g., terrestrial inputs, physical dynamics) is crucially important because trophic dynamics are a vital part of ecosystem integrity. This can be achieved by identifying organic matter sources that enter food webs along inshore-offshore transects. We hypothesised that regional hydrological structures over wide continental shelves directly control the benthic trophic functioning across the shelf. We investigated this issue along two transects in the northern ecosystem of the Bay of Biscay (north-eastern Atlantic). Carbon and nitrogen stable isotope analysis (SIA) and fatty acid analysis (FAA) were conducted on different complementary ecosystem compartments that include suspended particulate organic matter (POM), sedimentary organic matter (SOM), and benthic consumers such as bivalves, large crustaceans and demersal fish. Samples were collected from inshore shallow waters (at ∼1 m in depth) to more than 200 m in depth on the offshore shelf break. Results indicated strong discrepancies in stable isotope (SI) and fatty acid (FA) compositions in the sampled compartments between inshore and offshore areas, although nitrogen SI (δ15N) and FA trends were similar along both transects. Offshore the influence of a permanently stratified area (described previously as a ;cold pool;) was evident in both transects. The influence of this hydrological structure on benthic trophic functioning (i.e., on the food sources available for consumers) was especially apparent across the northern transect, due to unusual carbon isotope compositions (δ13C) in the compartments. At stations under the cold pool, SI and FA organism compositions indicated benthic trophic functioning based on a microbial food web, including a significant contribution of heterotrophic planktonic organisms and/or of SOM, notably in stations under the cold pool. On the contrary, inshore and shelf break areas were characterised by a microalgae-based food web (at least in part for the shelf break area, due to slope current and upwelling that can favour fresh primary production sinking on site). SIA and FAA were relevant and complementary tools, and consumers better medium- to long-term system integrators than POM samples, for depicting the trophic functioning and dynamics along inshore-offshore transects over continental shelves.

The Micronesia Challenge: Assessing the Relative Contribution of Stressors on Coral Reefs to Facilitate Science-to-Management Feedback

PubMed Central

Houk, Peter; Camacho, Rodney; Johnson, Steven; McLean, Matthew; Maxin, Selino; Anson, Jorg; Joseph, Eugene; Nedlic, Osamu; Luckymis, Marston; Adams, Katrina; Hess, Don; Kabua, Emma; Yalon, Anthony; Buthung, Eva; Graham, Curtis; Leberer, Trina; Taylor, Brett; van Woesik, Robert

2015-01-01

Fishing and pollution are chronic stressors that can prolong recovery of coral reefs and contribute to ecosystem decline. While this premise is generally accepted, management interventions are complicated because the contributions from individual stressors are difficult to distinguish. The present study examined the extent to which fishing pressure and pollution predicted progress towards the Micronesia Challenge, an international conservation strategy initiated by the political leaders of 6 nations to conserve at least 30% of marine resources by 2020. The analyses were rooted in a defined measure of coral-reef-ecosystem condition, comprised of biological metrics that described functional processes on coral reefs. We report that only 42% of the major reef habitats exceeded the ecosystem-condition threshold established by the Micronesia Challenge. Fishing pressure acting alone on outer reefs, or in combination with pollution in some lagoons, best predicted both the decline and variance in ecosystem condition. High variances among ecosystem-condition scores reflected the large gaps between the best and worst reefs, and suggested that the current scores were unlikely to remain stable through time because of low redundancy. Accounting for the presence of marine protected area (MPA) networks in statistical models did little to improve the models’ predictive capabilities, suggesting limited efficacy of MPAs when grouped together across the region. Yet, localized benefits of MPAs existed and are expected to increase over time. Sensitivity analyses suggested that (i) grazing by large herbivores, (ii) high functional diversity of herbivores, and (iii) high predator biomass were most sensitive to fishing pressure, and were required for high ecosystem-condition scores. Linking comprehensive fisheries management policies with these sensitive metrics, and targeting the management of pollution, will strengthen the Micronesia Challenge and preserve ecosystem services that coral reefs provide to societies in the face of climate change. PMID:26087252

The Micronesia Challenge: Assessing the Relative Contribution of Stressors on Coral Reefs to Facilitate Science-to-Management Feedback.

PubMed

Houk, Peter; Camacho, Rodney; Johnson, Steven; McLean, Matthew; Maxin, Selino; Anson, Jorg; Joseph, Eugene; Nedlic, Osamu; Luckymis, Marston; Adams, Katrina; Hess, Don; Kabua, Emma; Yalon, Anthony; Buthung, Eva; Graham, Curtis; Leberer, Trina; Taylor, Brett; van Woesik, Robert

2015-01-01

Fishing and pollution are chronic stressors that can prolong recovery of coral reefs and contribute to ecosystem decline. While this premise is generally accepted, management interventions are complicated because the contributions from individual stressors are difficult to distinguish. The present study examined the extent to which fishing pressure and pollution predicted progress towards the Micronesia Challenge, an international conservation strategy initiated by the political leaders of 6 nations to conserve at least 30% of marine resources by 2020. The analyses were rooted in a defined measure of coral-reef-ecosystem condition, comprised of biological metrics that described functional processes on coral reefs. We report that only 42% of the major reef habitats exceeded the ecosystem-condition threshold established by the Micronesia Challenge. Fishing pressure acting alone on outer reefs, or in combination with pollution in some lagoons, best predicted both the decline and variance in ecosystem condition. High variances among ecosystem-condition scores reflected the large gaps between the best and worst reefs, and suggested that the current scores were unlikely to remain stable through time because of low redundancy. Accounting for the presence of marine protected area (MPA) networks in statistical models did little to improve the models' predictive capabilities, suggesting limited efficacy of MPAs when grouped together across the region. Yet, localized benefits of MPAs existed and are expected to increase over time. Sensitivity analyses suggested that (i) grazing by large herbivores, (ii) high functional diversity of herbivores, and (iii) high predator biomass were most sensitive to fishing pressure, and were required for high ecosystem-condition scores. Linking comprehensive fisheries management policies with these sensitive metrics, and targeting the management of pollution, will strengthen the Micronesia Challenge and preserve ecosystem services that coral reefs provide to societies in the face of climate change.

Parameter Estimations of Dynamic Energy Budget (DEB) Model over the Life History of a Key Antarctic Species: The Antarctic Sea Star Odontaster validus Koehler, 1906.

PubMed

Agüera, Antonio; Collard, Marie; Jossart, Quentin; Moreau, Camille; Danis, Bruno

2015-01-01

Marine organisms in Antarctica are adapted to an extreme ecosystem including extremely stable temperatures and strong seasonality due to changes in day length. It is now largely accepted that Southern Ocean organisms are particularly vulnerable to global warming with some regions already being challenged by a rapid increase of temperature. Climate change affects both the physical and biotic components of marine ecosystems and will have an impact on the distribution and population dynamics of Antarctic marine organisms. To predict and assess the effect of climate change on marine ecosystems a more comprehensive knowledge of the life history and physiology of key species is urgently needed. In this study we estimate the Dynamic Energy Budget (DEB) model parameters for key benthic Antarctic species the sea star Odontaster validus using available information from literature and experiments. The DEB theory is unique in capturing the metabolic processes of an organism through its entire life cycle as a function of temperature and food availability. The DEB model allows for the inclusion of the different life history stages, and thus, becomes a tool that can be used to model lifetime feeding, growth, reproduction, and their responses to changes in biotic and abiotic conditions. The DEB model presented here includes the estimation of reproduction handling rules for the development of simultaneous oocyte cohorts within the gonad. Additionally it links the DEB model reserves to the pyloric caeca an organ whose function has long been ascribed to energy storage. Model parameters described a slowed down metabolism of long living animals that mature slowly. O. validus has a large reserve that-matching low maintenance costs- allow withstanding long periods of starvation. Gonad development is continuous and individual cohorts developed within the gonads grow in biomass following a power function of the age of the cohort. The DEB model developed here for O. validus allowed us to increase our knowledge on the ecophysiology of this species, providing new insights on the role of food availability and temperature on its life cycle and reproduction strategy.

Globalization, marine regime shifts and the Soviet Union

PubMed Central

Österblom, Henrik; Folke, Carl

2015-01-01

Regime shifts have been observed in marine ecosystems around the world, with climate and fishing suggested as major drivers of such shifts. The global and regional dynamics of the climate system have been studied in this context, and efforts to develop an analogous understanding of fishing activities are developing. Here, we investigate the timing of pelagic marine regime shifts in relation to the emergence of regional and global fishing activities of the Soviet Union. Our investigation of official catch statistics reflects that the Soviet Union was a major fishing actor in all large marine ecosystems where regime shifts have been documented, including in ecosystems where overfishing has been established as a key driver of these changes (in the Baltic and Black Seas and the Scotian Shelf). Globalization of Soviet Union fishing activities pushed exploitation to radically new levels and triggered regional and global governance responses for improved management. Since then, exploitation levels have remained and increased with new actors involved. Based on our exploratory work, we propose that a deeper understanding of the role of global fishing actors is central for improved management of marine ecosystems.

A compilation of quantitative functional traits for marine and freshwater crustacean zooplankton.

PubMed

Hébert, Marie-Pier; Beisner, Beatrix E; Maranger, Roxane

2016-04-01

This data compilation synthesizes 8609 individual observations and ranges of 13 traits from 201 freshwater and 191 marine crustacean taxa belonging to either Copepoda or Cladocera, two important zooplankton groups across all major aquatic habitats. Most data were gathered from the literature, with the balance being provided by zooplankton ecologists. With the aim of more fully assessing zooplankton effects on elemental processes such as nitrogen (N), phosphorus (P) and carbon (C) stocks and fluxes in aquatic ecosystems, this data set provides information on the following traits: body size (length and mass), trophic group, elemental and biochemical corporal composition (N, P, C, lipid and protein content), respiration rates, N- and P-excretion rates, as well as stoichiometric ratios. Although relationships for zooplankton metabolism as a function of body mass or requirements have been explored in the past three decades, data have not been systematically compiled nor examined from an integrative and large-scale perspective across crustacean taxa and habitat types. While this contribution likely represents the most comprehensive assembly of traits for both marine and freshwater species, this data set is not exhaustive either. As a result, this compilation also identifies knowledge gaps: a fact that should encourage researchers to disclose information they may have to help complete such databases. This trait matrix is made available for the first time in this data paper; prior to its release, the data set has been analyzed in a meta-analysis published as a companion paper. This data set should prove extremely valuable for aquatic ecologists for trait-based characterization of plankton community structure as well as biogeochemical modeling. These data are also well-suited for deriving shortcut relationships that predict more difficult to measure trait values, most of which can be directly related to ecosystem properties (i.e., effect traits), from simpler traits (e.g., body size), and for exploring patterns of trait variation within and amongst taxonomic units or ecosystem types. Overall, this data set is likely to provide new insights into the functional structure of zooplankton communities and increase our mechanistic understanding of the influence of these pivotal organisms on aquatic ecosystems. © 2016 by the Ecological Society of America.

Calcium Isotopic Evidence for Vulnerable Marine Ecosystem Structure Prior to the K/Pg Extinction.

PubMed

Martin, Jeremy E; Vincent, Peggy; Tacail, Théo; Khaldoune, Fatima; Jourani, Essaid; Bardet, Nathalie; Balter, Vincent

2017-06-05

The collapse of marine ecosystems during the end-Cretaceous mass extinction involved the base of the food chain [1] up to ubiquitous vertebrate apex predators [2-5]. Large marine reptiles became suddenly extinct at the Cretaceous-Paleogene (K/Pg) boundary, whereas other contemporaneous groups such as bothremydid turtles or dyrosaurid crocodylomorphs, although affected at the familial, genus, or species level, survived into post-crisis environments of the Paleocene [5-9] and could have found refuge in freshwater habitats [10-12]. A recent hypothesis proposes that the extinction of plesiosaurians and mosasaurids could have been caused by an important drop in sea level [13]. Mosasaurids are unusually diverse and locally abundant in the Maastrichtian phosphatic deposits of Morocco, and with large sharks and one species of elasmosaurid plesiosaurian recognized so far, contribute to an overabundance of apex predators [3, 7, 14, 15]. For this reason, high local diversity of marine reptiles exhibiting different body masses and a wealth of tooth morphologies hints at complex trophic interactions within this latest Cretaceous marine ecosystem. Using calcium isotopes, we investigated the trophic structure of this extinct assemblage. Our results are consistent with a calcium isotope pattern observed in modern marine ecosystems and show that plesiosaurians and mosasaurids indiscriminately fall in the tertiary piscivore group. This suggests that marine reptile apex predators relied onto a single dietary calcium source, compatible with the vulnerable wasp-waist food webs of the modern world [16]. This inferred peculiar ecosystem structure may help explain plesiosaurian and mosasaurid extinction following the end-Cretaceous biological crisis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ecomarkets for conservation and sustainable development in the coastal zone.

PubMed

Fujita, Rod; Lynham, John; Micheli, Fiorenza; Feinberg, Pasha G; Bourillón, Luis; Sáenz-Arroyo, Andrea; Markham, Alexander C

2013-05-01

Because conventional markets value only certain goods or services in the ocean (e.g. fish), other services provided by coastal and marine ecosystems that are not priced, paid for, or stewarded tend to become degraded. In fact, the very capacity of an ecosystem to produce a valued good or service is often reduced because conventional markets value only certain goods and services, rather than the productive capacity. Coastal socio-ecosystems are particularly susceptible to these market failures due to the lack of clear property rights, strong dependence on resource extraction, and other factors. Conservation strategies aimed at protecting unvalued coastal ecosystem services through regulation or spatial management (e.g. Marine Protected Areas) can be effective but often result in lost revenue and adverse social impacts, which, in turn, create conflict and opposition. Here, we describe 'ecomarkets' - markets and financial tools - that could, under the right conditions, generate value for broad portfolios of coastal ecosystem services while maintaining ecosystem structure and function by addressing the unique problems of the coastal zone, including the lack of clear management and exclusion rights. Just as coastal tenure and catch-share systems generate meaningful conservation and economic outcomes, it is possible to imagine other market mechanisms that do the same with respect to a variety of other coastal ecosystem goods and services. Rather than solely relying on extracting goods, these approaches could allow communities to diversify ecosystem uses and focus on long-term stewardship and conservation, while meeting development, food security, and human welfare goals. The creation of ecomarkets will be difficult in many cases, because rights and responsibilities must be devolved, new social contracts will be required, accountability systems must be created and enforced, and long-term patterns of behaviour must change. We argue that efforts to overcome these obstacles are justified, because these deep changes will strongly complement policies and tools such as Marine Protected Areas, coastal spatial management, and regulation, thereby helping to bring coastal conservation to scale. © 2012 The Authors. Biological Reviews © 2012 Cambridge Philosophical Society.

Marine Arctic Ecosystem Study (MARES): Pilot Project - Marine Mammal Tagging and Tracking

DTIC Science & Technology

2015-09-30

project . NOPP is an innovative collaboration of federal agencies that support ocean research partnerships among academia, government, industry, and...1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Marine Arctic Ecosystem Study (MARES): Pilot Project ...Francis.Wiese@stantec.com Award Number: N0001415IP00085 LONG-TERM GOALS The overarching goal of the MARES project is to understand the

Consequences of biodiversity loss diverge from expectation due to post-extinction compensatory responses

NASA Astrophysics Data System (ADS)

Thomsen, Matthias S.; Garcia, Clement; Bolam, Stefan G.; Parker, Ruth; Godbold, Jasmin A.; Solan, Martin

2017-03-01

Consensus has been reached that global biodiversity loss impairs ecosystem functioning and the sustainability of services beneficial to humanity. However, the ecosystem consequences of extinction in natural communities are moderated by compensatory species dynamics, yet these processes are rarely accounted for in impact assessments and seldom considered in conservation programmes. Here, we use marine invertebrate communities to parameterise numerical models of sediment bioturbation - a key mediator of biogeochemical cycling - to determine whether post-extinction compensatory mechanisms alter biodiversity-ecosystem function relations following non-random extinctions. We find that compensatory dynamics lead to trajectories of sediment mixing that diverge from those without compensation, and that the form, magnitude and variance of each probabilistic distribution is highly influenced by the type of compensation and the functional composition of surviving species. Our findings indicate that the generalized biodiversity-function relation curve, as derived from multiple empirical investigations of random species loss, is unlikely to yield representative predictions for ecosystem properties in natural systems because the influence of post-extinction community dynamics are under-represented. Recognition of this problem is fundamental to management and conservation efforts, and will be necessary to ensure future plans and adaptation strategies minimize the adverse impacts of the biodiversity crisis.

Specimen banking of marine organisms in the United States: Current status and long-term prospective

USGS Publications Warehouse

Becker, P.R.; Wise, S.A.; Thorsteinson, L.; Koster, B.J.; Rowles, T.

1997-01-01

A major part of the activities conducted over the last decade by the National Biomonitoring Specimen Bank (NBSB) has involved the archival of marine specimens collected by ongoing environmental monitoring programs. These archived specimens include bivalves, marine sediments, and fish tissues collected by the National Status and Trends and the Exxon Valdez Oil Spill Damage Assessment programs, and marine mammal tissues collected by the Marine Mammal Health and Stranding Response Program and the Alaska Marine Mammal Tissue Archival Project. In addition to supporting these programs, the specimens have been used to investigate circumpolar patterns of chlorinated hydrocarbon concentrations, genetic separation of marine animal stocks, baseline levels of essential and nonessential elements in marine mammals, and the potential risk to human consumers in the Arctic from anthropogenic contaminants found in local subsistence foods. The NBSB specimens represent a resource that has the potential for addressing future issues of marine environmental quality and ecosystem changes through retrospective analysis; however, an ecosystem-based food web approach would maximize this potential. The current status of the NBSB activities related to the banking of marine organisms is presented and discussed, the long-term prospective of these activities is presented, and the importance of an ecosystem-based food web monitoring approach to the value of specimen banking is discussed.

Otters, Marine

USGS Publications Warehouse

Estes, James A.; Bodkin, James L.; Ben-David, M.; Perrin, William F.; Würsing, Bernd; Thewissen, J.G.M.

2009-01-01

The otters (Mustelidae; Lutrinae) provide an exceptional perspective into the evolution of marine living by mammals. Most extant marine mammals (e.g. the cetaceans, pinnipeds, and sirenians) have been so highly modified by long periods of selection for life in the sea that they bear little resemblance to their terrestrial ancestors. Marine otters, in contrast, are more recent expatriates from freshwater habitats and some species still live in both environments. Contrasts among species within the otters, and among the otters, terrestrial mammals, and the more highly adapted pinnipeds and cetaceans provide powerful insights into mammalian adaptations to life in the sea (Estes, 1989). Among the marine mammals, sea otters (Enhydra lutris, Fig. 1) provide the clearest understanding of consumer-induced effects on ecosystem function. This is due in part to opportunities provided by history and in part to the relative ease with which shallow coastal systems where sea otters live can be observed and studied. Although more difficult to study than sea otters, other otter species reveal the connectivity among the marine, freshwater, and terrestrial systems. These three qualities of the otters – their comparative biology, their role as predators, and their role as agents of ecosystem connectivity – are what make them interesting to marine mammalogy.The following account provides a broad overview of the comparative biology and ecology of the otters, with particular emphasis on those species or populations that live in the sea. Sea otters are features prominently, in part because they live exclusively in the sea whereas other otters have obligate associations with freshwater and terrestrial environments (Kenyon, 1969; Riedman and Estes, 1990).

Marine anoxia and delayed Earth system recovery after the end-Permian extinction

PubMed Central

Lau, Kimberly V.; Maher, Kate; Altiner, Demir; Kelley, Brian M.; Kump, Lee R.; Lehrmann, Daniel J.; Silva-Tamayo, Juan Carlos; Weaver, Karrie L.; Yu, Meiyi; Payne, Jonathan L.

2016-01-01

Delayed Earth system recovery following the end-Permian mass extinction is often attributed to severe ocean anoxia. However, the extent and duration of Early Triassic anoxia remains poorly constrained. Here we use paired records of uranium concentrations ([U]) and 238U/235U isotopic compositions (δ238U) of Upper Permian−Upper Triassic marine limestones from China and Turkey to quantify variations in global seafloor redox conditions. We observe abrupt decreases in [U] and δ238U across the end-Permian extinction horizon, from ∼3 ppm and −0.15‰ to ∼0.3 ppm and −0.77‰, followed by a gradual return to preextinction values over the subsequent 5 million years. These trends imply a factor of 100 increase in the extent of seafloor anoxia and suggest the presence of a shallow oxygen minimum zone (OMZ) that inhibited the recovery of benthic animal diversity and marine ecosystem function. We hypothesize that in the Early Triassic oceans—characterized by prolonged shallow anoxia that may have impinged onto continental shelves—global biogeochemical cycles and marine ecosystem structure became more sensitive to variation in the position of the OMZ. Under this hypothesis, the Middle Triassic decline in bottom water anoxia, stabilization of biogeochemical cycles, and diversification of marine animals together reflect the development of a deeper and less extensive OMZ, which regulated Earth system recovery following the end-Permian catastrophe. PMID:26884155

Marine anoxia and delayed Earth system recovery after the end-Permian extinction.

PubMed

Lau, Kimberly V; Maher, Kate; Altiner, Demir; Kelley, Brian M; Kump, Lee R; Lehrmann, Daniel J; Silva-Tamayo, Juan Carlos; Weaver, Karrie L; Yu, Meiyi; Payne, Jonathan L

2016-03-01

Delayed Earth system recovery following the end-Permian mass extinction is often attributed to severe ocean anoxia. However, the extent and duration of Early Triassic anoxia remains poorly constrained. Here we use paired records of uranium concentrations ([U]) and (238)U/(235)U isotopic compositions (δ(238)U) of Upper Permian-Upper Triassic marine limestones from China and Turkey to quantify variations in global seafloor redox conditions. We observe abrupt decreases in [U] and δ(238)U across the end-Permian extinction horizon, from ∼3 ppm and -0.15‰ to ∼0.3 ppm and -0.77‰, followed by a gradual return to preextinction values over the subsequent 5 million years. These trends imply a factor of 100 increase in the extent of seafloor anoxia and suggest the presence of a shallow oxygen minimum zone (OMZ) that inhibited the recovery of benthic animal diversity and marine ecosystem function. We hypothesize that in the Early Triassic oceans-characterized by prolonged shallow anoxia that may have impinged onto continental shelves-global biogeochemical cycles and marine ecosystem structure became more sensitive to variation in the position of the OMZ. Under this hypothesis, the Middle Triassic decline in bottom water anoxia, stabilization of biogeochemical cycles, and diversification of marine animals together reflect the development of a deeper and less extensive OMZ, which regulated Earth system recovery following the end-Permian catastrophe.

Bioluminescence in the Sea

NASA Astrophysics Data System (ADS)

Haddock, Steven H. D.; Moline, Mark A.; Case, James F.

2010-01-01

Bioluminescence spans all oceanic dimensions and has evolved many times—from bacteria to fish—to powerfully influence behavioral and ecosystem dynamics. New methods and technology have brought great advances in understanding of the molecular basis of bioluminescence, its physiological control, and its significance in marine communities. Novel tools derived from understanding the chemistry of natural light-producing molecules have led to countless valuable applications, culminating recently in a related Nobel Prize. Marine organisms utilize bioluminescence for vital functions ranging from defense to reproduction. To understand these interactions and the distributions of luminous organisms, new instruments and platforms allow observations on individual to oceanographic scales. This review explores recent advances, including the chemical and molecular, phylogenetic and functional, community and oceanographic aspects of bioluminescence.

Ecosystem Based Management in Transition: From Ocean Policy to Application

NASA Astrophysics Data System (ADS)

Saumweber, W. J.; Goldman, E.

2016-02-01

Ecosystem-based management (EBM) has been proposed as a means to improve resource management and stewardship for more than two decades. Over this history, its exact goals and approaches have evolved in concert with advances in science and policy, including a greater understanding of ecosystem function, valuation, and thresholds for change, along with direct reference to EBM principles in statute, regulation, and other Executive Actions. Most recently, and explicitly, the Administration's National Ocean Policy (NOP) called for the development of a Federal EBM framework that would outline principles and guidelines for implementing EBM under existing authorities. This cross-agency framework has yet to be developed, but, the NOP, and related Administration initiatives, have resulted in the practical application of EBM principles in several issue-specific policy initiatives ranging from fisheries and marine protected area management to coastal adaptation and water resource infrastructure investment. In each case, the application of EBM principles uses apparently unique policy mechanisms (e.g. marine planning, ecosystem services assessment, adaptive management, dynamic ocean management, etc.). Despite differences in terminology and policy context, each of these policy initiatives is linked at its core to concepts of integrated and adaptive management that consider broad ecosystem function and services. This practical history of EBM implementation speaks to both the challenges and opportunities in broad incorporation of EBM across diverse policy initiatives and frameworks. We suggest that the continued growth of EBM as a practical policy concept will require a move away from broad frameworks, and towards the identification of specific resource management issues and accompanying policy levers with which to address those issues. In order to promote this progression, Federal policy should recognize and articulate the diverse set of policy mechanisms encompassed under the rubric of EBM and seek to require similar approaches across the spectra of resource management issues.

Ecosystem Based Management in Transition: From Ocean Policy to Application

NASA Astrophysics Data System (ADS)

Saumweber, W. J.; Goldman, E.

2016-12-01

Ecosystem-based management (EBM) has been proposed as a means to improve resource management and stewardship for more than two decades. Over this history, its exact goals and approaches have evolved in concert with advances in science and policy, including a greater understanding of ecosystem function, valuation, and thresholds for change, along with direct reference to EBM principles in statute, regulation, and other Executive Actions. Most recently, and explicitly, the Administration's National Ocean Policy (NOP) called for the development of a Federal EBM framework that would outline principles and guidelines for implementing EBM under existing authorities. This cross-agency framework has yet to be developed, but, the NOP, and related Administration initiatives, have resulted in the practical application of EBM principles in several issue-specific policy initiatives ranging from fisheries and marine protected area management to coastal adaptation and water resource infrastructure investment. In each case, the application of EBM principles uses apparently unique policy mechanisms (e.g. marine planning, ecosystem services assessment, adaptive management, dynamic ocean management, etc.). Despite differences in terminology and policy context, each of these policy initiatives is linked at its core to concepts of integrated and adaptive management that consider broad ecosystem function and services. This practical history of EBM implementation speaks to both the challenges and opportunities in broad incorporation of EBM across diverse policy initiatives and frameworks. We suggest that the continued growth of EBM as a practical policy concept will require a move away from broad frameworks, and towards the identification of specific resource management issues and accompanying policy levers with which to address those issues. In order to promote this progression, Federal policy should recognize and articulate the diverse set of policy mechanisms encompassed under the rubric of EBM and seek to require similar approaches across the spectra of resource management issues.

Eukaryotic Life Inhabits Rhodolith-forming Coralline Algae (Hapalidiales, Rhodophyta), Remarkable Marine Benthic Microhabitats

NASA Astrophysics Data System (ADS)

Krayesky-Self, Sherry; Schmidt, William E.; Phung, Delena; Henry, Caroline; Sauvage, Thomas; Camacho, Olga; Felgenhauer, Bruce E.; Fredericq, Suzanne

2017-04-01

Rhodoliths are benthic calcium carbonate nodules accreted by crustose coralline red algae which recently have been identified as useful indicators of biomineral changes resulting from global climate change and ocean acidification. This study highlights the discovery that the interior of rhodoliths are marine biodiversity hotspots that function as seedbanks and temporary reservoirs of previously unknown stages in the life history of ecologically important dinoflagellate and haptophyte microalgae. Whereas the studied rhodoliths originated from offshore deep bank pinnacles in the northwestern Gulf of Mexico, the present study opens the door to assess the universality of endolithic stages among bloom-forming microalgae spanning different phyla, some of public health concerns (Prorocentrum) in marine ecosystems worldwide.

Ecological impact of the end-Cretaceous extinction on lamniform sharks.

PubMed

Belben, Rachel A; Underwood, Charlie J; Johanson, Zerina; Twitchett, Richard J

2017-01-01

Lamniform sharks are apex marine predators undergoing dramatic local and regional decline worldwide, with consequences for marine ecosystems that are difficult to predict. Through their long history, lamniform sharks have faced widespread extinction, and understanding those 'natural experiments' may help constrain predictions, placing the current crisis in evolutionary context. Here we show, using novel morphometric analyses of fossil shark teeth, that the end-Cretaceous extinction of many sharks had major ecological consequences. Post-extinction ecosystems supported lower diversity and disparity of lamniforms, and were dominated by significantly smaller sharks with slimmer, smoother and less robust teeth. Tooth shape is intimately associated with ecology, feeding and prey type, and by integrating data from extant sharks we show that latest Cretaceous sharks occupied similar niches to modern lamniforms, implying similar ecosystem structure and function. By comparison, species in the depauperate post-extinction community occupied niches most similar to those of juvenile sand tigers (Carcharias taurus). Our data show that quantitative tooth morphometrics can distinguish lamniform sharks due to dietary differences, providing critical insights into ecological consequences of past extinction episodes.

Ecological impact of the end-Cretaceous extinction on lamniform sharks

PubMed Central

Belben, Rachel A.; Underwood, Charlie J.; Johanson, Zerina; Twitchett, Richard J.

2017-01-01

Lamniform sharks are apex marine predators undergoing dramatic local and regional decline worldwide, with consequences for marine ecosystems that are difficult to predict. Through their long history, lamniform sharks have faced widespread extinction, and understanding those ‘natural experiments’ may help constrain predictions, placing the current crisis in evolutionary context. Here we show, using novel morphometric analyses of fossil shark teeth, that the end-Cretaceous extinction of many sharks had major ecological consequences. Post-extinction ecosystems supported lower diversity and disparity of lamniforms, and were dominated by significantly smaller sharks with slimmer, smoother and less robust teeth. Tooth shape is intimately associated with ecology, feeding and prey type, and by integrating data from extant sharks we show that latest Cretaceous sharks occupied similar niches to modern lamniforms, implying similar ecosystem structure and function. By comparison, species in the depauperate post-extinction community occupied niches most similar to those of juvenile sand tigers (Carcharias taurus). Our data show that quantitative tooth morphometrics can distinguish lamniform sharks due to dietary differences, providing critical insights into ecological consequences of past extinction episodes. PMID:28591222

75 FR 5566 - NOAA Cooperative Institutes (CIs): (1) A CI To Support NOAA Research Facilities in the Pacific...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-02-03

... Northwest, (2) A CI for Southwestern U.S. Marine Ecosystems, Climate and Ocean Studies, and (3) A... Southwestern U.S. Marine Ecosystems, Climate and Ocean Studies, and (3) A Southeastern Regional CI for...

Nutrient loading and consumers: Agents of change in open-coast macrophyte assemblages

PubMed Central

Nielsen, Karina J.

2003-01-01

Human activities are significantly altering nutrient regimes and the abundance of consumers in coastal ecosystems. A field experiment in an open-coast, upwelling ecosystem showed that small increases in nutrients increased the biomass and evenness of tide pool macrophytes where consumer abundance and nutrient loading rates were low. Consumers, when abundant, had negative effects on the diversity and biomass of macrophytes. Nutrient loading increases and consumers are less abundant and efficient as wave exposure increases along open coastlines. Experimentally reversing the natural state of nutrient supply and consumer pressure at a wave-protected site to match wave-exposed sites caused the structure of the macrophyte assemblage to converge on that found naturally in wave-exposed pools. The increases in evenness and abundance were driven by increases in structurally complex functional groups. In contrast, increased nutrient loading in semienclosed marine or estuarine ecosystems is typically associated with declines in macrophyte diversity because of increases in structurally simple and opportunistic functional groups. If nutrient concentration of upwelled waters changes with climatic warming or increasing frequency of El Niños, as predicted by some climate models, these results suggest that macrophyte abundance and evenness along wave-swept open-coasts will also change. Macrophytes represent a significant fraction of continental shelf production and provide important habitat for many marine species. The combined effects of shifting nutrient regimes and overexploitation of consumers may have unexpected consequences for the structure and functioning of open-coast communities. PMID:12796509

Nutrient loading and consumers: agents of change in open-coast macrophyte assemblages.

PubMed

Nielsen, Karina J

2003-06-24

Human activities are significantly altering nutrient regimes and the abundance of consumers in coastal ecosystems. A field experiment in an open-coast, upwelling ecosystem showed that small increases in nutrients increased the biomass and evenness of tide pool macrophytes where consumer abundance and nutrient loading rates were low. Consumers, when abundant, had negative effects on the diversity and biomass of macrophytes. Nutrient loading increases and consumers are less abundant and efficient as wave exposure increases along open coastlines. Experimentally reversing the natural state of nutrient supply and consumer pressure at a wave-protected site to match wave-exposed sites caused the structure of the macrophyte assemblage to converge on that found naturally in wave-exposed pools. The increases in evenness and abundance were driven by increases in structurally complex functional groups. In contrast, increased nutrient loading in semienclosed marine or estuarine ecosystems is typically associated with declines in macrophyte diversity because of increases in structurally simple and opportunistic functional groups. If nutrient concentration of upwelled waters changes with climatic warming or increasing frequency of El Niños, as predicted by some climate models, these results suggest that macrophyte abundance and evenness along wave-swept open-coasts will also change. Macrophytes represent a significant fraction of continental shelf production and provide important habitat for many marine species. The combined effects of shifting nutrient regimes and overexploitation of consumers may have unexpected consequences for the structure and functioning of open-coast communities.

Ecological structure and function differs between habitats dominated by seagrasses and green seaweeds.

PubMed

Tuya, Fernando; Png-Gonzalez, Lydia; Riera, Rodrigo; Haroun, Ricardo; Espino, Fernando

2014-07-01

Marine vegetated habitats, e.g. seagrass meadows, deliver essential functions and services to coastal ecosystems and human welfare. Impacts induced by humans, however, have facilitated the replacement of seagrasses by alternative vegetation, e.g. green rhizophytic seaweeds. The implications of habitat shifts for ecosystem attributes and processes and the services they deliver remain poorly known. In this study, we compared ecosystem structure and function between Cymodocea nodosa seagrass meadows and bottoms dominated by Caulerpa prolifera, a green, native, rhizophytic seaweed, through 5 ecological proxies: (i) primary production (via community metabolism), (ii) composition and abundance of epifauna (a proxy for provision of habitat for epifauna), composition and abundance of (iii) small-sized (juvenile) and (iv) large-sized (adult) fishes (proxies for provision of habitat for fishes), and (v) sediment retention (a proxy for sediment stabilization). Four of these proxies were greater in C. nodosa seagrass meadows than in C. prolifera beds: gross primary productivity (∼1.4 times), the total abundance, species density and biomass of small-sized fishes (∼2.1, 1.3 and 1.3 times, respectively), the total abundance and species density of large-sized fishes (∼3.6 and 1.5 times, respectively), and sediment stabilization (∼1.4 times). In contrast, the total abundance and species density of epifauna was larger (∼3.1 and 1.7 times, respectively) in C. prolifera than in C. nodosa seagrass beds. These results suggest that ecosystem structure and function may differ if seagrasses are replaced by green rhizophytic seaweeds. Importantly, ecosystem functions may not be appropriate surrogates for one another. As a result, assessments of ecosystem services associated with ecosystem functions cannot be based on exclusively one service that is expected to benefit other services. Copyright © 2014 Elsevier Ltd. All rights reserved.

A Policy Alternative Analysis and Simplified Scoring Method to Assess Policy Options for Marine Conservation Areas

NASA Astrophysics Data System (ADS)

Sharuga, S. M.; Reams, M.

2016-02-01

Traditional approaches to marine conservation and management are increasingly being found as inadequate; and, consequently, more complex ecosystem-based approaches to protecting marine ecosystems are growing in popularity. Ecosystem-based approaches, however, can be particularly challenging at a local level where resources and knowledge of specific marine conservation components may be limited. Marine conservation areas are known by a variety of names globally, but can be divided into four general types: Marine Protected Areas (MPAs), Marine Reserves, Fishery Reserves, and Ecological Reserves (i.e. "no take zones"). Each type of conservation area involves specific objectives, program elements and likely socioeconomic consequences. As an aid to community stakeholders and decision makers considering establishment of a marine conservation area, a simple method to compare and score the objectives and attributes of these four approaches is presented. A range of evaluation criteria are considered, including conservation of biodiversity and habitat, effective fishery management, overall cost-effectiveness, fairness to current users, enhancement of recreational activities, fairness to taxpayers, and conservation of genetic diversity. Environmental and socioeconomic costs and benefits of each type of conservation area are also considered. When exploring options for managing the marine environment, particular resource conservation needs must be evaluated individually on a case-by-case basis and the type of conservation area established must be tailored accordingly. However, MPAs are often more successful than other conservation areas because they offer a compromise between the needs of society and the environment, and therefore represent a viable option for ecosystem-based management.

A Policy Alternative Analysis and Simplified Scoring Method to Assess Policy Options for Marine Conservation Areas

NASA Astrophysics Data System (ADS)

Sharuga, S. M.; Reams, M.

2016-12-01

Traditional approaches to marine conservation and management are increasingly being found as inadequate; and, consequently, more complex ecosystem-based approaches to protecting marine ecosystems are growing in popularity. Ecosystem-based approaches, however, can be particularly challenging at a local level where resources and knowledge of specific marine conservation components may be limited. Marine conservation areas are known by a variety of names globally, but can be divided into four general types: Marine Protected Areas (MPAs), Marine Reserves, Fishery Reserves, and Ecological Reserves (i.e. "no take zones"). Each type of conservation area involves specific objectives, program elements and likely socioeconomic consequences. As an aid to community stakeholders and decision makers considering establishment of a marine conservation area, a simple method to compare and score the objectives and attributes of these four approaches is presented. A range of evaluation criteria are considered, including conservation of biodiversity and habitat, effective fishery management, overall cost-effectiveness, fairness to current users, enhancement of recreational activities, fairness to taxpayers, and conservation of genetic diversity. Environmental and socioeconomic costs and benefits of each type of conservation area are also considered. When exploring options for managing the marine environment, particular resource conservation needs must be evaluated individually on a case-by-case basis and the type of conservation area established must be tailored accordingly. However, MPAs are often more successful than other conservation areas because they offer a compromise between the needs of society and the environment, and therefore represent a viable option for ecosystem-based management.

The structure of Mediterranean rocky reef ecosystems across environmental and human gradients, and conservation implications

USGS Publications Warehouse

Sala, Enric; Ballesteros, Enric; Dendrinos, Panagiotis; Di Franco, Antonio; Ferretti, Francesco; Foley, David; Fraschetti, Simonetta; Friedlander, Alan M.; Garrabou, Joaquim; Guclusoy, Harun; Guidetti, Paolo; Halpern, Benjamin S.; Hereu, Bernat; Karamanlidis, Alexandros A.; Kizilkaya, Zafer; Macpherson, Enrique; Mangialajo, Luisa; Mariani, Simone; Micheli, Fiorenza; Pais, Antonio; Riser, Kristin; Rosenberg, Andrew A.; Sales, Marta; Selkoe, Kimberly A.; Starr, Rick; Tomas, Fiona; Zabala, Mikel

2012-01-01

Historical exploitation of the Mediterranean Sea and the absence of rigorous baselines makes it difficult to evaluate the current health of the marine ecosystems and the efficacy of conservation actions at the ecosystem level. Here we establish the first current baseline and gradient of ecosystem structure of nearshore rocky reefs at the Mediterranean scale. We conducted underwater surveys in 14 marine protected areas and 18 open access sites across the Mediterranean, and across a 31-fold range of fish biomass (from 3.8 to 118 g m-2). Our data showed remarkable variation in the structure of rocky reef ecosystems. Multivariate analysis showed three alternative community states: (1) large fish biomass and reefs dominated by non-canopy algae, (2) lower fish biomass but abundant native algal canopies and suspension feeders, and (3) low fish biomass and extensive barrens, with areas covered by turf algae. Our results suggest that the healthiest shallow rocky reef ecosystems in the Mediterranean have both large fish and algal biomass. Protection level and primary production were the only variables significantly correlated to community biomass structure. Fish biomass was significantly larger in well-enforced no-take marine reserves, but there were no significant differences between multi-use marine protected areas (which allow some fishing) and open access areas at the regional scale. The gradients reported here represent a trajectory of degradation that can be used to assess the health of any similar habitat in the Mediterranean, and to evaluate the efficacy of marine protected areas.

The structure of Mediterranean rocky reef ecosystems across environmental and human gradients, and conservation implications.

PubMed

Sala, Enric; Ballesteros, Enric; Dendrinos, Panagiotis; Di Franco, Antonio; Ferretti, Francesco; Foley, David; Fraschetti, Simonetta; Friedlander, Alan; Garrabou, Joaquim; Güçlüsoy, Harun; Guidetti, Paolo; Halpern, Benjamin S; Hereu, Bernat; Karamanlidis, Alexandros A; Kizilkaya, Zafer; Macpherson, Enrique; Mangialajo, Luisa; Mariani, Simone; Micheli, Fiorenza; Pais, Antonio; Riser, Kristin; Rosenberg, Andrew A; Sales, Marta; Selkoe, Kimberly A; Starr, Rick; Tomas, Fiona; Zabala, Mikel

2012-01-01

Historical exploitation of the Mediterranean Sea and the absence of rigorous baselines makes it difficult to evaluate the current health of the marine ecosystems and the efficacy of conservation actions at the ecosystem level. Here we establish the first current baseline and gradient of ecosystem structure of nearshore rocky reefs at the Mediterranean scale. We conducted underwater surveys in 14 marine protected areas and 18 open access sites across the Mediterranean, and across a 31-fold range of fish biomass (from 3.8 to 118 g m(-2)). Our data showed remarkable variation in the structure of rocky reef ecosystems. Multivariate analysis showed three alternative community states: (1) large fish biomass and reefs dominated by non-canopy algae, (2) lower fish biomass but abundant native algal canopies and suspension feeders, and (3) low fish biomass and extensive barrens, with areas covered by turf algae. Our results suggest that the healthiest shallow rocky reef ecosystems in the Mediterranean have both large fish and algal biomass. Protection level and primary production were the only variables significantly correlated to community biomass structure. Fish biomass was significantly larger in well-enforced no-take marine reserves, but there were no significant differences between multi-use marine protected areas (which allow some fishing) and open access areas at the regional scale. The gradients reported here represent a trajectory of degradation that can be used to assess the health of any similar habitat in the Mediterranean, and to evaluate the efficacy of marine protected areas.

Emerging conservation challenges and prospects in an era of offshore hydrocarbon exploration and exploitation.

PubMed

Kark, Salit; Brokovich, Eran; Mazor, Tessa; Levin, Noam

2015-12-01

Globally, extensive marine areas important for biodiversity conservation and ecosystem functioning are undergoing exploration and extraction of oil and natural gas resources. Such operations are expanding to previously inaccessible deep waters and other frontier regions, while conservation-related legislation and planning is often lacking. Conservation challenges arising from offshore hydrocarbon development are wide-ranging. These challenges include threats to ecosystems and marine species from oil spills, negative impacts on native biodiversity from invasive species colonizing drilling infrastructure, and increased political conflicts that can delay conservation actions. With mounting offshore operations, conservationists need to urgently consider some possible opportunities that could be leveraged for conservation. Leveraging options, as part of multi-billion dollar marine hydrocarbon operations, include the use of facilities and costly equipment of the deep and ultra-deep hydrocarbon industry for deep-sea conservation research and monitoring and establishing new conservation research, practice, and monitoring funds and environmental offsetting schemes. The conservation community, including conservation scientists, should become more involved in the earliest planning and exploration phases and remain involved throughout the operations so as to influence decision making and promote continuous monitoring of biodiversity and ecosystems. A prompt response by conservation professionals to offshore oil and gas developments can mitigate impacts of future decisions and actions of the industry and governments. New environmental decision support tools can be used to explicitly incorporate the impacts of hydrocarbon operations on biodiversity into marine spatial and conservation plans and thus allow for optimum trade-offs among multiple objectives, costs, and risks. © 2015 Society for Conservation Biology.

Adaptation to Impacts of Greenhouse Gases on the Ocean (Invited)

NASA Astrophysics Data System (ADS)

Caldeira, K.

2010-12-01

Greenhouse gases are producing changes in ocean temperature and circulation, and these changes are already adversely affecting marine biota. Furthermore, carbon dioxide is absorbed by the oceans from the atmosphere, and this too is already adversely affecting some marine ecosystems. And, of course, sea-level rise affects both what is above and below the waterline. Clearly, the most effective approach to limit the negative impacts of climate change and acidification on the marine environment is to greatly diminish the rate of greenhouse gas emissions. However, there are other measures that can be taken to limit some of the negative effects of these stresses in the marine environment. Marine ecosystems are subject to multiple stresses, including overfishing, pollution, and loss of coastal wetlands that often serve as nurseries for the open ocean. The adaptive capacity of marine environments can be improved by limiting these other stresses. If current carbon dioxide emission trends continue, for some cases (e.g., coral reefs), it is possible that no amount of reduction in other stresses can offset the increase in stresses posed by warming and acidification. For other cases (e.g., blue-water top-predator fisheries), better fisheries management might yield improved population health despite continued warming and acidification. In addition to reducing stresses so as to improve the adaptive capacity of marine ecosystems, there is also the issue of adaptation in human communities that depend on this changing marine environment. For example, communities that depend on services provided by coral reefs may need to locate alternative foundations for their economies. The fishery industry will need to adapt to changes in fish abundance, timing and location. Most of the things we would like to do to increase the adaptive capacity of marine ecosystems (e.g., reduce fishing pressure, reduce coastal pollution, preserve coastal wetlands) are things that would make sense to do even in the absence of threats from climate change and ocean acidification. Therefore, these measures represent “no regrets” policy options for the marine environment. Nevertheless, even with adaptive policies in place, continued greenhouse gas emissions increasingly risk damaging marine ecosystems and the human communities that depend on them.

Biotechnological Applications of Marine Enzymes From Algae, Bacteria, Fungi, and Sponges.

PubMed

Parte, S; Sirisha, V L; D'Souza, J S

Diversity is the hallmark of all life forms that inhabit the soil, air, water, and land. All these habitats pose their unique inherent challenges so as to breed the "fittest" creatures. Similarly, the biodiversity from the marine ecosystem has evolved unique properties due to challenging environment. These challenges include permafrost regions to hydrothermal vents, oceanic trenches to abyssal plains, fluctuating saline conditions, pH, temperature, light, atmospheric pressure, and the availability of nutrients. Oceans occupy 75% of the earth's surface and harbor most ancient and diverse forms of organisms (algae, bacteria, fungi, sponges, etc.), serving as an excellent source of natural bioactive molecules, novel therapeutic compounds, and enzymes. In this chapter, we introduce enzyme technology, its current state of the art, unique enzyme properties, and the biocatalytic potential of marine algal, bacterial, fungal, and sponge enzymes that have indeed boosted the Marine Biotechnology Industry. Researchers began exploring marine enzymes, and today they are preferred over the chemical catalysts for biotechnological applications and functions, encompassing various sectors, namely, domestic, industrial, commercial, and healthcare. Next, we summarize the plausible pros and cons: the challenges encountered in the process of discovery of the potent compounds and bioactive metabolites such as biocatalysts/enzymes of biomedical, therapeutic, biotechnological, and industrial significance. The field of Marine Enzyme Technology has recently assumed importance, and if it receives further boost, it could successfully substitute other chemical sources of enzymes useful for industrial and commercial purposes and may prove as a beneficial and ecofriendly option. With appropriate directions and encouragement, marine enzyme technology can sustain the rising demand for enzyme production while maintaining the ecological balance, provided any undesired exploitation of the marine ecosystem is avoided. © 2017 Elsevier Inc. All rights reserved.

Marine protected areas increase resilience among coral reef communities.

PubMed

Mellin, Camille; Aaron MacNeil, M; Cheal, Alistair J; Emslie, Michael J; Julian Caley, M

2016-06-01

With marine biodiversity declining globally at accelerating rates, maximising the effectiveness of conservation has become a key goal for local, national and international regulators. Marine protected areas (MPAs) have been widely advocated for conserving and managing marine biodiversity yet, despite extensive research, their benefits for conserving non-target species and wider ecosystem functions remain unclear. Here, we demonstrate that MPAs can increase the resilience of coral reef communities to natural disturbances, including coral bleaching, coral diseases, Acanthaster planci outbreaks and storms. Using a 20-year time series from Australia's Great Barrier Reef, we show that within MPAs, (1) reef community composition was 21-38% more stable; (2) the magnitude of disturbance impacts was 30% lower and (3) subsequent recovery was 20% faster that in adjacent unprotected habitats. Our results demonstrate that MPAs can increase the resilience of marine communities to natural disturbance possibly through herbivory, trophic cascades and portfolio effects. © 2016 John Wiley & Sons Ltd/CNRS.

An introduced Asian parasite threatens northeastern Pacific estuarine ecosystems

USDA-ARS?s Scientific Manuscript database

We test a prevalent assumption in marine ecology that species are native to where they are found until contrary evidence appears. The native assumption significantly biases interpretations of marine community and ecosystem dynamics if it results in oversight of critically important introduced specie...

A probabilistic process model for pelagic marine ecosystems informed by Bayesian inverse analysis

EPA Science Inventory

Marine ecosystems are complex systems with multiple pathways that produce feedback cycles, which may lead to unanticipated effects. Models abstract this complexity and allow us to predict, understand, and hypothesize. In ecological models, however, the paucity of empirical data...

Kernel Density Surface Modelling as a Means to Identify Significant Concentrations of Vulnerable Marine Ecosystem Indicators

PubMed Central

Kenchington, Ellen; Murillo, Francisco Javier; Lirette, Camille; Sacau, Mar; Koen-Alonso, Mariano; Kenny, Andrew; Ollerhead, Neil; Wareham, Vonda; Beazley, Lindsay

2014-01-01

The United Nations General Assembly Resolution 61/105, concerning sustainable fisheries in the marine ecosystem, calls for the protection of vulnerable marine ecosystems (VME) from destructive fishing practices. Subsequently, the Food and Agriculture Organization (FAO) produced guidelines for identification of VME indicator species/taxa to assist in the implementation of the resolution, but recommended the development of case-specific operational definitions for their application. We applied kernel density estimation (KDE) to research vessel trawl survey data from inside the fishing footprint of the Northwest Atlantic Fisheries Organization (NAFO) Regulatory Area in the high seas of the northwest Atlantic to create biomass density surfaces for four VME indicator taxa: large-sized sponges, sea pens, small and large gorgonian corals. These VME indicator taxa were identified previously by NAFO using the fragility, life history characteristics and structural complexity criteria presented by FAO, along with an evaluation of their recovery trajectories. KDE, a non-parametric neighbour-based smoothing function, has been used previously in ecology to identify hotspots, that is, areas of relatively high biomass/abundance. We present a novel approach of examining relative changes in area under polygons created from encircling successive biomass categories on the KDE surface to identify “significant concentrations” of biomass, which we equate to VMEs. This allows identification of the VMEs from the broader distribution of the species in the study area. We provide independent assessments of the VMEs so identified using underwater images, benthic sampling with other gear types (dredges, cores), and/or published species distribution models of probability of occurrence, as available. For each VME indicator taxon we provide a brief review of their ecological function which will be important in future assessments of significant adverse impact on these habitats here and elsewhere. PMID:25289667

Kernel density surface modelling as a means to identify significant concentrations of vulnerable marine ecosystem indicators.

PubMed

Kenchington, Ellen; Murillo, Francisco Javier; Lirette, Camille; Sacau, Mar; Koen-Alonso, Mariano; Kenny, Andrew; Ollerhead, Neil; Wareham, Vonda; Beazley, Lindsay

2014-01-01

The United Nations General Assembly Resolution 61/105, concerning sustainable fisheries in the marine ecosystem, calls for the protection of vulnerable marine ecosystems (VME) from destructive fishing practices. Subsequently, the Food and Agriculture Organization (FAO) produced guidelines for identification of VME indicator species/taxa to assist in the implementation of the resolution, but recommended the development of case-specific operational definitions for their application. We applied kernel density estimation (KDE) to research vessel trawl survey data from inside the fishing footprint of the Northwest Atlantic Fisheries Organization (NAFO) Regulatory Area in the high seas of the northwest Atlantic to create biomass density surfaces for four VME indicator taxa: large-sized sponges, sea pens, small and large gorgonian corals. These VME indicator taxa were identified previously by NAFO using the fragility, life history characteristics and structural complexity criteria presented by FAO, along with an evaluation of their recovery trajectories. KDE, a non-parametric neighbour-based smoothing function, has been used previously in ecology to identify hotspots, that is, areas of relatively high biomass/abundance. We present a novel approach of examining relative changes in area under polygons created from encircling successive biomass categories on the KDE surface to identify "significant concentrations" of biomass, which we equate to VMEs. This allows identification of the VMEs from the broader distribution of the species in the study area. We provide independent assessments of the VMEs so identified using underwater images, benthic sampling with other gear types (dredges, cores), and/or published species distribution models of probability of occurrence, as available. For each VME indicator taxon we provide a brief review of their ecological function which will be important in future assessments of significant adverse impact on these habitats here and elsewhere.

An Insight into Phage Diversity at Environmental Habitats using Comparative Metagenomics Approach.

PubMed

Parmar, Krupa; Dafale, Nishant; Pal, Rajesh; Tikariha, Hitesh; Purohit, Hemant

2018-02-01

Bacteriophages play significant role in driving microbial diversity; however, little is known about the diversity of phages in different ecosystems. A dynamic predator-prey mechanism called "kill the winner" suggests the elimination of most active bacterial populations through phages. Thus, interaction between phage and host has an effect on the composition of microbial communities in ecosystems. In this study, secondary phage metagenome data from aquatic habitats: wastewater treatment plant (WWTP), fresh, marine, and hot water spring habitat were analyzed using MG-RAST and STAMP tools to explore the diversity of the viruses. Differential relative abundance of phage families-Siphoviridae (34%) and Myoviridae (26%) in WWTP, Myoviridae (30%) and Podoviridae (23%) in fresh water, and Myoviridae (41%) and Podoviridae (8%) in marine-was found to be a discriminating factor among four habitats while Rudiviridae (9%), Globuloviridae (8%), and Lipothrixviridae (1%) were exclusively observed in hot water spring. Subsequently, at genera level, Bpp-1-like virus, Chlorovirus, and T4-like virus were found abundant in WWTP, fresh, and marine habitat, respectively. PCA analysis revealed completely disparate composition of phage in hot water spring from other three ecosystems. Similar analysis of relative abundance of functional features corroborated observations from taxa analysis. Functional features corresponding to phage packaging machinery, replication, integration and excision, and gene transfer discriminated among four habitats. The comparative metagenomics approach exhibited genetically distinct phage communities among four habitats. Results revealed that selective distribution of phage communities would help in understanding the role of phages in food chains, nutrient cycling, and microbial ecology. Study of specific phages would also help in controlling environmental pathogens including MDR bacterial populations using phage therapy approach by selective mining and isolation of phages against specific pathogens persisting in a given environment.

Tipping elements in the Arctic marine ecosystem.

PubMed

Duarte, Carlos M; Agustí, Susana; Wassmann, Paul; Arrieta, Jesús M; Alcaraz, Miquel; Coello, Alexandra; Marbà, Núria; Hendriks, Iris E; Holding, Johnna; García-Zarandona, Iñigo; Kritzberg, Emma; Vaqué, Dolors

2012-02-01

The Arctic marine ecosystem contains multiple elements that present alternative states. The most obvious of which is an Arctic Ocean largely covered by an ice sheet in summer versus one largely devoid of such cover. Ecosystems under pressure typically shift between such alternative states in an abrupt, rather than smooth manner, with the level of forcing required for shifting this status termed threshold or tipping point. Loss of Arctic ice due to anthropogenic climate change is accelerating, with the extent of Arctic sea ice displaying increased variance at present, a leading indicator of the proximity of a possible tipping point. Reduced ice extent is expected, in turn, to trigger a number of additional tipping elements, physical, chemical, and biological, in motion, with potentially large impacts on the Arctic marine ecosystem.

Megacities and large urban agglomerations in the coastal zone: interactions between atmosphere, land, and marine ecosystems.

PubMed

von Glasow, Roland; Jickells, Tim D; Baklanov, Alexander; Carmichael, Gregory R; Church, Tom M; Gallardo, Laura; Hughes, Claire; Kanakidou, Maria; Liss, Peter S; Mee, Laurence; Raine, Robin; Ramachandran, Purvaja; Ramesh, R; Sundseth, Kyrre; Tsunogai, Urumu; Uematsu, Mitsuo; Zhu, Tong

2013-02-01

Megacities are not only important drivers for socio-economic development but also sources of environmental challenges. Many megacities and large urban agglomerations are located in the coastal zone where land, atmosphere, and ocean meet, posing multiple environmental challenges which we consider here. The atmospheric flow around megacities is complicated by urban heat island effects and topographic flows and sea breezes and influences air pollution and human health. The outflow of polluted air over the ocean perturbs biogeochemical processes. Contaminant inputs can damage downstream coastal zone ecosystem function and resources including fisheries, induce harmful algal blooms and feedback to the atmosphere via marine emissions. The scale of influence of megacities in the coastal zone is hundreds to thousands of kilometers in the atmosphere and tens to hundreds of kilometers in the ocean. We list research needs to further our understanding of coastal megacities with the ultimate aim to improve their environmental management.

Bacterial communities in sediment of a Mediterranean marine protected area.

PubMed

Catania, Valentina; Sarà, Gianluca; Settanni, Luca; Quatrini, Paola

2017-04-01

Biodiversity is crucial in preservation of ecosystems, and bacterial communities play an indispensable role for the functioning of marine ecosystems. The Mediterranean marine protected area (MPA) "Capo Gallo-Isola delle Femmine" was instituted to preserve marine biodiversity. The bacterial diversity associated with MPA sediment was compared with that from sediment of an adjacent harbour exposed to intense nautical traffic. The MPA sediment showed higher diversity with respect to the impacted site. A 16S rDNA clone library of the MPA sediment allowed the identification of 7 phyla: Proteobacteria (78%), Firmicutes (11%), Acidobacteria (3%), Actinobacteria (3%), Bacteroidetes (2%), Planctomycetes (2%), and Cyanobacteria (1%). Analysis of the hydrocarbon (HC)-degrading bacteria was performed using enrichment cultures. Most of the MPA sediment isolates were affiliated with Gram-positive G+C rich bacteria, whereas the majority of taxa in the harbour sediment clustered with Alpha- and Gammaproteobacteria; no Gram-positive HC degraders were isolated from the harbour sediment. Our results show that protection probably has an influence on bacterial diversity, and suggest the importance of monitoring the effects of protection at microbial level as well. This study creates a baseline of data that can be used to assess changes over time in bacterial communities associated with a Mediterranean MPA.

Ecosystem behavior at Bermuda Station [open quotes]S[close quotes] and ocean weather station [open quotes]India[close quotes]: A general circulation model and observational analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fasham, M.J.R.; Sarmiento, J.L.; Slater, R.D.

1993-06-01

One important theme of modern biological oceanography has been the attempt to develop models of how the marine ecosystem responds to variations in the physical forcing functions such as solar radiation and the wind field. The authors have addressed the problem by embedding simple ecosystem models into a seasonally forced three-dimensional general circulation model of the North Atlantic ocean. In this paper first, some of the underlying biological assumptions of the ecosystem model are presented, followed by an analysis of how well the model predicts the seasonal cycle of the biological variables at Bermuda Station s' and Ocean Weather Stationmore » India. The model gives a good overall fit to the observations but does not faithfully model the whole seasonal ecosystem model. 57 refs., 25 figs., 5 tabs.« less

Impacts of biodiversity loss on ocean ecosystem services.

PubMed

Worm, Boris; Barbier, Edward B; Beaumont, Nicola; Duffy, J Emmett; Folke, Carl; Halpern, Benjamin S; Jackson, Jeremy B C; Lotze, Heike K; Micheli, Fiorenza; Palumbi, Stephen R; Sala, Enric; Selkoe, Kimberley A; Stachowicz, John J; Watson, Reg

2006-11-03

Human-dominated marine ecosystems are experiencing accelerating loss of populations and species, with largely unknown consequences. We analyzed local experiments, long-term regional time series, and global fisheries data to test how biodiversity loss affects marine ecosystem services across temporal and spatial scales. Overall, rates of resource collapse increased and recovery potential, stability, and water quality decreased exponentially with declining diversity. Restoration of biodiversity, in contrast, increased productivity fourfold and decreased variability by 21%, on average. We conclude that marine biodiversity loss is increasingly impairing the ocean's capacity to provide food, maintain water quality, and recover from perturbations. Yet available data suggest that at this point, these trends are still reversible.

Confronting the coral reef crisis.

PubMed

Bellwood, D R; Hughes, T P; Folke, C; Nyström, M

2004-06-24

The worldwide decline of coral reefs calls for an urgent reassessment of current management practices. Confronting large-scale crises requires a major scaling-up of management efforts based on an improved understanding of the ecological processes that underlie reef resilience. Managing for improved resilience, incorporating the role of human activity in shaping ecosystems, provides a basis for coping with uncertainty, future changes and ecological surprises. Here we review the ecological roles of critical functional groups (for both corals and reef fishes) that are fundamental to understanding resilience and avoiding phase shifts from coral dominance to less desirable, degraded ecosystems. We identify striking biogeographic differences in the species richness and composition of functional groups, which highlight the vulnerability of Caribbean reef ecosystems. These findings have profound implications for restoration of degraded reefs, management of fisheries, and the focus on marine protected areas and biodiversity hotspots as priorities for conservation.

50 CFR 300.112 - Harvesting permits.

Code of Federal Regulations, 2011 CFR

2011-10-01

... sale, change in ownership, or other disposition of the vessel to the Assistant Administrator within 15... ensure stable recruitment. (3) Cause changes or increase the risk of changes in the marine ecosystem that..., the effects of associated activities on the marine ecosystem and of the effects of environmental...

50 CFR 300.112 - Harvesting permits.

Code of Federal Regulations, 2010 CFR

2010-10-01

... sale, change in ownership, or other disposition of the vessel to the Assistant Administrator within 15... ensure stable recruitment. (3) Cause changes or increase the risk of changes in the marine ecosystem that..., the effects of associated activities on the marine ecosystem and of the effects of environmental...

Cross-disciplinarity in the advance of Antarctic ecosystem research.

PubMed

Gutt, J; Isla, E; Bertler, A N; Bodeker, G E; Bracegirdle, T J; Cavanagh, R D; Comiso, J C; Convey, P; Cummings, V; De Conto, R; De Master, D; di Prisco, G; d'Ovidio, F; Griffiths, H J; Khan, A L; López-Martínez, J; Murray, A E; Nielsen, U N; Ott, S; Post, A; Ropert-Coudert, Y; Saucède, T; Scherer, R; Schiaparelli, S; Schloss, I R; Smith, C R; Stefels, J; Stevens, C; Strugnell, J M; Trimborn, S; Verde, C; Verleyen, E; Wall, D H; Wilson, N G; Xavier, J C

2018-02-01

The biodiversity, ecosystem services and climate variability of the Antarctic continent and the Southern Ocean are major components of the whole Earth system. Antarctic ecosystems are driven more strongly by the physical environment than many other marine and terrestrial ecosystems. As a consequence, to understand ecological functioning, cross-disciplinary studies are especially important in Antarctic research. The conceptual study presented here is based on a workshop initiated by the Research Programme Antarctic Thresholds - Ecosystem Resilience and Adaptation of the Scientific Committee on Antarctic Research, which focussed on challenges in identifying and applying cross-disciplinary approaches in the Antarctic. Novel ideas and first steps in their implementation were clustered into eight themes. These ranged from scale problems, through risk maps, and organism/ecosystem responses to multiple environmental changes and evolutionary processes. Scaling models and data across different spatial and temporal scales were identified as an overarching challenge. Approaches to bridge gaps in Antarctic research programmes included multi-disciplinary monitoring, linking biomolecular findings and simulated physical environments, as well as integrative ecological modelling. The results of advanced cross-disciplinary approaches can contribute significantly to our knowledge of Antarctic and global ecosystem functioning, the consequences of climate change, and to global assessments that ultimately benefit humankind. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

Changes in the northern Gulf of St. Lawrence ecosystem estimated by inverse modelling: Evidence of a fishery-induced regime shift?

NASA Astrophysics Data System (ADS)

Savenkoff, Claude; Castonguay, Martin; Chabot, Denis; Hammill, Mike O.; Bourdages, Hugo; Morissette, Lyne

2007-07-01

Mass-balance models have been constructed using inverse methodology for the northern Gulf of St. Lawrence for the mid-1980s, the mid-1990s, and the early 2000s to describe ecosystem structure, trophic group interactions, and the effects of fishing and predation on the ecosystem for each time period. Our analyses indicate that the ecosystem structure shifted dramatically from one previously dominated by demersal (cod, redfish) and small-bodied forage (e.g., capelin, mackerel, herring, shrimp) species to one now dominated by small-bodied forage species. Overfishing removed a functional group in the late 1980s, large piscivorous fish (primarily cod and redfish), which has not recovered 14 years after the cessation of heavy fishing. This has left only marine mammals as top predators during the mid-1990s, and marine mammals and small Greenland halibut during the early 2000s. Predation by marine mammals on fish increased from the mid-1980s to the early 2000s while predation by large fish on fish decreased. Capelin and shrimp, the main prey in each period, showed an increase in biomass over the three periods. A switch in the main predators of capelin from cod to marine mammals occurred, while Greenland halibut progressively replaced cod as shrimp predators. Overfishing influenced community structure directly through preferential removal of larger-bodied fishes and indirectly through predation release because larger-bodied fishes exerted top-down control upon other community species or competed with other species for the same prey. Our modelling estimates showed that a change in predation structure or flows at the top of the trophic system led to changes in predation at all lower trophic levels in the northern Gulf of St. Lawrence. These changes represent a case of fishery-induced regime shift.

Marine protected areas increase temporal stability of community structure, but not density or diversity, of tropical seagrass fish communities

PubMed Central

Jiddawi, Narriman S.; Eklöf, Johan S.

2017-01-01

Marine protected areas (MPAs) have been shown to increase long-term temporal stability of fish communities and enhance ecosystem resilience to anthropogenic disturbance. Yet, the potential ability of MPAs to buffer effects of environmental variability at shorter time scales remains widely unknown. In the tropics, the yearly monsoon cycle is a major natural force affecting marine organisms in tropical regions, and its timing and severity are predicted to change over the coming century, with potentially severe effects on marine organisms, ecosystems and ecosystem services. Here, we assessed the ability of MPAs to buffer effects of monsoon seasonality on seagrass-associated fish communities, using a field survey in two MPAs (no-take zones) and two unprotected (open-access) sites around Zanzibar (Tanzania). We assessed the temporal stability of fish density and community structure within and outside MPAs during three monsoon seasons in 2014–2015, and investigated several possible mechanisms that could regulate temporal stability. Our results show that MPAs did not affect fish density and diversity, but that juvenile fish densities were temporally more stable within MPAs. Second, fish community structure was more stable within MPAs for juvenile and adult fish, but not for subadult fish or the total fish community. Third, the observed effects may be due to a combination of direct and indirect (seagrass-mediated) effects of seasonality and, potentially, fluctuating fishing pressure outside MPAs. In summary, these MPAs may not have the ability to enhance fish density and diversity and to buffer effects of monsoon seasonality on the whole fish community. However, they may increase the temporal stability of certain groups, such as juvenile fish. Consequently, our results question whether MPAs play a general role in the maintenance of biodiversity and ecosystem functioning under changing environmental conditions in tropical seagrass fish communities. PMID:28854231

Comparison between Atlantic and Pacific Tropical Marine Coastal Ecosystems: Community Structure, Ecological Processes, and Productivity. Results and Scientific Papers of a Unesco/COMAR Workshop (Suva, Fiji, March 24-29, 1986). Unesco Reports in Marine Science 46.

ERIC Educational Resources Information Center

Birkeland, Charles, Ed.

This report presents the Unesco workshop conclusions concerning important differences among tropical seas in terms of ecological processes in coastal marine ecosystems, and the corresponding implications for resource management guidelines. The conclusions result from the presentation and discussion of eight review papers which are included in this…

Biodiversity's big wet secret: the global distribution of marine biological records reveals chronic under-exploration of the deep pelagic ocean.

PubMed

Webb, Thomas J; Vanden Berghe, Edward; O'Dor, Ron

2010-08-02

Understanding the distribution of marine biodiversity is a crucial first step towards the effective and sustainable management of marine ecosystems. Recent efforts to collate location records from marine surveys enable us to assemble a global picture of recorded marine biodiversity. They also effectively highlight gaps in our knowledge of particular marine regions. In particular, the deep pelagic ocean--the largest biome on Earth--is chronically under-represented in global databases of marine biodiversity. We use data from the Ocean Biogeographic Information System to plot the position in the water column of ca 7 million records of marine species occurrences. Records from relatively shallow waters dominate this global picture of recorded marine biodiversity. In addition, standardising the number of records from regions of the ocean differing in depth reveals that regardless of ocean depth, most records come either from surface waters or the sea bed. Midwater biodiversity is drastically under-represented. The deep pelagic ocean is the largest habitat by volume on Earth, yet it remains biodiversity's big wet secret, as it is hugely under-represented in global databases of marine biological records. Given both its value in the provision of a range of ecosystem services, and its vulnerability to threats including overfishing and climate change, there is a pressing need to increase our knowledge of Earth's largest ecosystem.

Multi-year assessment of coastal planktonic fungi reveals environmental drivers of diversity and abundance

PubMed Central

Taylor, Joe D; Cunliffe, Michael

2016-01-01

Mycoplankton have so far been a neglected component of pelagic marine ecosystems, having been poorly studied relative to other plankton groups. Currently, there is a lack of understanding of how mycoplankton diversity changes through time, and the identity of controlling environmental drivers. Using Fungi-specific high-throughput sequencing and quantitative PCR analysis of plankton DNA samples collected over 6 years from the coastal biodiversity time series site Station L4 situated off Plymouth (UK), we have assessed changes in the temporal variability of mycoplankton diversity and abundance in relation to co-occurring environmental variables. Mycoplankton diversity at Station L4 was dominated by Ascomycota, Basidiomycota and Chytridiomycota, with several orders within these phyla frequently abundant and dominant in multiple years. Repeating interannual mycoplankton blooms were linked to potential controlling environmental drivers, including nitrogen availability and temperature. Specific relationships between mycoplankton and other plankton groups were also identified, with seasonal chytrid blooms matching diatom blooms in consecutive years. Mycoplankton α-diversity was greatest during periods of reduced salinity at Station L4, indicative of riverine input to the ecosystem. Mycoplankton abundance also increased during periods of reduced salinity, and when potential substrate availability was increased, including particulate organic matter. This study has identified possible controlling environmental drivers of mycoplankton diversity and abundance in a coastal sea ecosystem, and therefore sheds new light on the biology and ecology of an enigmatic marine plankton group. Mycoplankton have several potential functional roles, including saprotrophs and parasites, that should now be considered within the consensus view of pelagic ecosystem functioning and services. PMID:26943623

The Structure of Mediterranean Rocky Reef Ecosystems across Environmental and Human Gradients, and Conservation Implications

PubMed Central

Sala, Enric; Ballesteros, Enric; Dendrinos, Panagiotis; Di Franco, Antonio; Ferretti, Francesco; Foley, David; Fraschetti, Simonetta; Friedlander, Alan; Garrabou, Joaquim; Güçlüsoy, Harun; Guidetti, Paolo; Halpern, Benjamin S.; Hereu, Bernat; Karamanlidis, Alexandros A.; Kizilkaya, Zafer; Macpherson, Enrique; Mangialajo, Luisa; Mariani, Simone; Micheli, Fiorenza; Pais, Antonio; Riser, Kristin; Rosenberg, Andrew A.; Sales, Marta; Selkoe, Kimberly A.; Starr, Rick; Tomas, Fiona; Zabala, Mikel

2012-01-01

Historical exploitation of the Mediterranean Sea and the absence of rigorous baselines makes it difficult to evaluate the current health of the marine ecosystems and the efficacy of conservation actions at the ecosystem level. Here we establish the first current baseline and gradient of ecosystem structure of nearshore rocky reefs at the Mediterranean scale. We conducted underwater surveys in 14 marine protected areas and 18 open access sites across the Mediterranean, and across a 31-fold range of fish biomass (from 3.8 to 118 g m−2). Our data showed remarkable variation in the structure of rocky reef ecosystems. Multivariate analysis showed three alternative community states: (1) large fish biomass and reefs dominated by non-canopy algae, (2) lower fish biomass but abundant native algal canopies and suspension feeders, and (3) low fish biomass and extensive barrens, with areas covered by turf algae. Our results suggest that the healthiest shallow rocky reef ecosystems in the Mediterranean have both large fish and algal biomass. Protection level and primary production were the only variables significantly correlated to community biomass structure. Fish biomass was significantly larger in well-enforced no-take marine reserves, but there were no significant differences between multi-use marine protected areas (which allow some fishing) and open access areas at the regional scale. The gradients reported here represent a trajectory of degradation that can be used to assess the health of any similar habitat in the Mediterranean, and to evaluate the efficacy of marine protected areas. PMID:22393445

An ecosystem model of an exploited southern Mediterranean shelf region (Gulf of Gabes, Tunisia) and a comparison with other Mediterranean ecosystem model properties

NASA Astrophysics Data System (ADS)

Hattab, Tarek; Ben Rais Lasram, Frida; Albouy, Camille; Romdhane, Mohamed Salah; Jarboui, Othman; Halouani, Ghassen; Cury, Philippe; Le Loc'h, François

2013-12-01

In this paper, we describe an exploited continental shelf ecosystem (Gulf of Gabes) in the southern Mediterranean Sea using an Ecopath mass-balance model. This allowed us to determine the structure and functioning of this ecosystem and assess the impacts of fishing upon it. The model represents the average state of the ecosystem between 2000 and 2005. It includes 41 functional groups, which encompass the entire trophic spectrum from phytoplankton to higher trophic levels (e.g., fishes, birds, and mammals), and also considers the fishing activities in the area (five fleets). Model results highlight an important bentho-pelagic coupling in the system due to the links between plankton and benthic invertebrates through detritus. A comparison of this model with those developed for other continental shelf regions in the Mediterranean (i.e., the southern Catalan, the northern-central Adriatic, and the northern Aegean Seas) emphasizes similar patterns in their trophic functioning. Low and medium trophic levels (i.e., zooplankton, benthic molluscs, and polychaetes) and sharks were identified as playing key ecosystem roles and were classified as keystone groups. An analysis of ecosystem attributes indicated that the Gulf of Gabes is the least mature (i.e., in the earliest stages of ecosystem development) of the four ecosystems that were compared and it is suggested that this is due, at least in part, to the impacts of fishing. Bottom trawling was identified as having the widest-ranging impacts across the different functional groups and the largest impacts on some commercially-targeted demersal fish species. Several exploitation indices highlighted that the Gulf of Gabes ecosystem is highly exploited, a finding which is supported by stock assessment outcomes. This suggests that it is unlikely that the gulf can be fished at sustainable levels, a situation which is similar to other marine ecosystems in the Mediterranean Sea.

Ecosystem service provision: an operational way for marine biodiversity conservation and management.

PubMed

Cognetti, Giuseppe; Maltagliati, Ferruccio

2010-11-01

Since no extensive conceptual framework has been developed on the issues of ecosystem service (ES) and service provider (SP) in the marine environment, we have made an attempt to apply these to the conservation and management of marine biodiversity. Within this context, an accurate individuation of SPs, namely the biological component of a given ecosystem that supports human activities is fundamental. SPs are the agents responsible for making the ES-based approach operational. The application of these concepts to the marine environment should be based on an model different to the terrestrial one. In the latter, the basic model envisages a matrix of a human-altered landscape with fragments of original biodiversity; conversely, in the marine environment the model provides fragments where human activities are carried out and the matrix is represented by the original biodiversity. We have identified three main classes of ES provision: in natural, disturbed and human-controlled environments. Economic valuation of marine ESs is an essential condition for making conservation strategies financially sustainable, as it may stimulate the perceived need for investing in protection and exploitation of marine resources. Copyright © 2010 Elsevier Ltd. All rights reserved.

The trophic fingerprint of marine fisheries.

PubMed

Branch, Trevor A; Watson, Reg; Fulton, Elizabeth A; Jennings, Simon; McGilliard, Carey R; Pablico, Grace T; Ricard, Daniel; Tracey, Sean R

2010-11-18

Biodiversity indicators provide a vital window on the state of the planet, guiding policy development and management. The most widely adopted marine indicator is mean trophic level (MTL) from catches, intended to detect shifts from high-trophic-level predators to low-trophic-level invertebrates and plankton-feeders. This indicator underpins reported trends in human impacts, declining when predators collapse ("fishing down marine food webs") and when low-trophic-level fisheries expand ("fishing through marine food webs"). The assumption is that catch MTL measures changes in ecosystem MTL and biodiversity. Here we combine model predictions with global assessments of MTL from catches, trawl surveys and fisheries stock assessments and find that catch MTL does not reliably predict changes in marine ecosystems. Instead, catch MTL trends often diverge from ecosystem MTL trends obtained from surveys and assessments. In contrast to previous findings of rapid declines in catch MTL, we observe recent increases in catch, survey and assessment MTL. However, catches from most trophic levels are rising, which can intensify fishery collapses even when MTL trends are stable or increasing. To detect fishing impacts on marine biodiversity, we recommend greater efforts to measure true abundance trends for marine species, especially those most vulnerable to fishing.

Assessing the impact of edaphic factors on coastal ecosystem functions in a tropical island using electromagnetic-induction

NASA Astrophysics Data System (ADS)

Lynch, N. E.; Wuddivira, M.; Oatham, M.

2013-12-01

The small islands in the low-lying states of the Caribbean Basin are among the most vulnerable to sea level rise caused by climate change. Bequia, a tropical Grenadine island, is particularly susceptible due to its small land mass, limited natural resources and an economy that is touristic and marine based. Consultation with stakeholders on sustainable livelihoods revealed that degradation of the coastal ecosystem is occurring with progressing time. Consequently, the island is losing its beneficial ecosystem services and its natural attractiveness leading to declining revenue base, increasing food security risk and job losses. We propose that with sea level rise, soil salinity increases further inland leading to degradation of coastal zones and ecosystem functions. Using geophysical techniques and standard sampling procedures we observationally investigated the spatial and temporal impacts of soil salinization due to sea level changes on the ecosystem functions of five coastal areas in the seven square mile island of Bequia. We analyzed soil, tidal, rainfall data and historical aerial imagery to assess the impact of soil salinity on the ecosystem of Bequia. Our results show extreme seasonal salinity variability with increased salinity inland during the dry season months of January to May. This was significantly influenced by the fluctuation of seasonal water content and temperature. A complete time-based analysis ensures the development of adaptation strategies to coastal change for sustainable provisioning of ecosystem services for Bequia and other Caribbean Islands with minimum ecological and economic losses.

Ecosystem Health Assessment in the Pearl River Estuary of China by Considering Ecosystem Coordination

PubMed Central

Chen, Xiaoyan; Gao, Huiwang; Yao, Xiaohong; Chen, Zhenhua; Fang, Hongda; Ye, Shufeng

2013-01-01

Marine ecosystem is a complex nonlinear system. However, ecosystem health assessment conventionally builds on a linear superposition of changes in ecosystem components and probably fails to evaluate nonlinear interactions among various components. To better reflect the intrinsic interactions and their impacts on ecosystem health, an ecosystem coordination index, defined as the matching level of ecosystem structure/services, is proposed and incorporated into the ecosystem health index for a systematic diagnosis in the Pearl River Estuary, China. The analysis results show that the ecosystem health index over the last three decades decreased from 0.91 to 0.50, indicating deteriorating from healthy to unhealthy status. The health index is 3–16% lower than that calculated using the common method without considering ecosystem coordination. Ecosystem health degradation in the Pearl River Estuary manifested as significant decreases in structure/services and somewhat mismatching among them. Overall, the introduction of coordination in ecosystem health assessment could improve the understanding of the mechanism of marine ecosystem change and facilitate effective restoration of ecosystem health. PMID:23894670

Incorporating ecosystem services into environmental management of deep-seabed mining

NASA Astrophysics Data System (ADS)

Le, Jennifer T.; Levin, Lisa A.; Carson, Richard T.

2017-03-01

Accelerated exploration of minerals in the deep sea over the past decade has raised the likelihood that commercial mining of the deep seabed will commence in the near future. Environmental concerns create a growing urgency for development of environmental regulations under commercial exploitation. Here, we consider an ecosystem services approach to the environmental policy and management of deep-sea mineral resources. Ecosystem services link the environment and human well-being, and can help improve sustainability and stewardship of the deep sea by providing a quantitative basis for decision-making. This paper briefly reviews ecosystem services provided by habitats targeted for deep-seabed mining (hydrothermal vents, seamounts, nodule provinces, and phosphate-rich margins), and presents practical steps to incorporate ecosystem services into deep-seabed mining regulation. The linkages and translation between ecosystem structure, ecological function (including supporting services), and ecosystem services are highlighted as generating human benefits. We consider criteria for identifying which ecosystem services are vulnerable to potential mining impacts, the role of ecological functions in providing ecosystem services, development of ecosystem service indicators, valuation of ecosystem services, and implementation of ecosystem services concepts. The first three steps put ecosystem services into a deep-seabed mining context; the last two steps help to incorporate ecosystem services into a management and decision-making framework. Phases of environmental planning discussed in the context of ecosystem services include conducting strategic environmental assessments, collecting baseline data, monitoring, establishing marine protected areas, assessing cumulative impacts, identifying thresholds and triggers, and creating an environmental damage compensation regime. We also identify knowledge gaps that need to be addressed in order to operationalize ecosystem services concepts in deep-seabed mining regulation and propose potential tools to fill them.

Assessing the effects of large mobile predators on ecosystem connectivity.

PubMed

McCauley, Douglas J; Young, Hillary S; Dunbar, Robert B; Estes, James A; Semmens, Brice X; Micheli, Fiorenza

2012-09-01

Large predators are often highly mobile and can traverse and use multiple habitats. We know surprisingly little about how predator mobility determines important processes of ecosystem connectivity. Here we used a variety of data sources drawn from Palmyra Atoll, a remote tropical marine ecosystem where large predators remain in high abundance, to investigate how these animals foster connectivity. Our results indicate that three of Palmyra's most abundant large predators (e.g., two reef sharks and one snapper) use resources from different habitats creating important linkages across ecosystems. Observations of cross-system foraging such as this have important implications for the understanding of ecosystem functioning, the management of large-predator populations, and the design of conservation measures intended to protect whole ecosystems. In the face of widespread declines of large, mobile predators, it is important that resource managers, policy makers, and ecologists work to understand how these predators create connectivity and to determine the impact that their depletions may be having on the integrity of these linkages.

Guide to the ecological systems of Puerto Rico

Treesearch

G. Miller; A.E. Lugo

2009-01-01

This guide is an introduction to the ecological systems of Puerto Rico. It covers the diversity of ecological systems in the island, their most common plant and animal species, and salient aspects of their structure and functioning. Terrestrial, wetland, coastal, and marine ecosystems are included, as well as agroforest and urban systems. The discussion of the...

Recreational impacts on the fauna of Australian coastal marine ecosystems.

PubMed

Hardiman, Nigel; Burgin, Shelley

2010-11-01

This paper reviews recent research into the ecological impacts of recreation and tourism on coastal marine fauna in Australia. Despite the high and growing importance of water-based recreation to the Australian economy, and the known fragility of many Australian ecosystems, there has been relatively limited research into the effects of marine tourism and recreation, infrastructure and activities, on aquatic resources. In this paper we have reviewed the ecological impacts on fauna that are caused by outdoor recreation (including tourism) in Australian coastal marine ecosystems. We predict that the single most potentially severe impact of recreation may be the introduction and/or dispersal of non-indigenous species of marine organisms by recreational vessels. Such introductions, together with other impacts due to human activities have the potential to increasingly degrade recreation destinations. In response, governments have introduced a wide range of legislative tools (e.g., impact assessment, protected area reservation) to manage the recreational industry. It would appear, however, that these instruments are not always appropriately applied. Copyright 2010 Elsevier Ltd. All rights reserved.

Effectiveness of marine protected areas in managing the drivers of ecosystem change: a case of Mnazi Bay Marine Park, Tanzania.

PubMed

Machumu, Milali Ernest; Yakupitiyage, Amararatne

2013-04-01

Marine protected areas (MPAs) are being promoted in Tanzania to mitigate the drivers of ecosystem change such as overfishing and other anthropogenic impacts on marine resources. The effectiveness of MPAs in managing those drivers was assessed in three ecological zones, seafront, mangrove, and riverine of Mnazi Bay Marine Park, using Participatory Community Analysis techniques, questionnaire survey, checklist and fishery resource assessment methods. Eleven major drivers of ecosystem change were identified. Resource dependence had a major effect in all ecological zones of the park. The results indicated that the park's legislations/regulations, management procedures, and conservation efforts are reasonably effective in managing its resources. The positive signs accrued from conservation efforts have been realized by the communities in terms of increased catch/income, awareness and compliance. However, some natural and anthropogenic drivers continued to threaten the park's sustainability. Furthermore, implementation of resource use and benefit sharing mechanisms still remained a considerable challenge to be addressed.

Marine mammals' influence on ecosystem processes affecting fisheries in the Barents Sea is trivial.

PubMed

Corkeron, Peter J

2009-04-23

Some interpretations of ecosystem-based fishery management include culling marine mammals as an integral component. The current Norwegian policy on marine mammal management is one example. Scientific support for this policy includes the Scenario Barents Sea (SBS) models. These modelled interactions between cod, Gadus morhua, herring, Clupea harengus, capelin, Mallotus villosus and northern minke whales, Balaenoptera acutorostrata. Adding harp seals Phoca groenlandica into this top-down modelling approach resulted in unrealistic model outputs. Another set of models of the Barents Sea fish-fisheries system focused on interactions within and between the three fish populations, fisheries and climate. These model key processes of the system successfully. Continuing calls to support the SBS models despite their failure suggest a belief that marine mammal predation must be a problem for fisheries. The best available scientific evidence provides no justification for marine mammal culls as a primary component of an ecosystem-based approach to managing the fisheries of the Barents Sea.

Marine ecosystem modeling beyond the box: using GIS to study carbon fluxes in a coastal ecosystem.

PubMed

Wijnbladh, Erik; Jönsson, Bror Fredrik; Kumblad, Linda

2006-12-01

Studies of carbon fluxes in marine ecosystems are often done by using box model approaches with basin size boxes, or highly resolved 3D models, and an emphasis on the pelagic component of the ecosystem. Those approaches work well in the ocean proper, but can give rise to considerable problems when applied to coastal systems, because of the scale of certain ecological niches and the fact that benthic organisms are the dominant functional group of the ecosystem. In addition, 3D models require an extensive modeling effort. In this project, an intermediate approach based on a high resolution (20x20 m) GIS data-grid has been developed for the coastal ecosystem in the Laxemar area (Baltic Sea, Sweden) based on a number of different site investigations. The model has been developed in the context of a safety assessment project for a proposed nuclear waste repository, in which the fate of hypothetically released radionuclides from the planned repository is estimated. The assessment project requires not only a good understanding of the ecosystem dynamics at the site, but also quantification of stocks and flows of matter in the system. The data-grid was then used to set up a carbon budget describing the spatial distribution of biomass, primary production, net ecosystem production and thus where carbon sinks and sources are located in the area. From these results, it was clear that there was a large variation in ecosystem characteristics within the basins and, on a larger scale, that the inner areas are net producing and the outer areas net respiring, even in shallow phytobenthic communities. Benthic processes had a similar or larger influence on carbon fluxes as advective processes in inner areas, whereas the opposite appears to be true in the outer basins. As many radionuclides are expected to follow the pathways of organic matter in the environment, these findings enhance our abilities to realistically describe and predict their fate in the ecosystem.

Arctic marine fishes and their fisheries in light of global change

PubMed Central

Christiansen, Jørgen S; Mecklenburg, Catherine W; Karamushko, Oleg V

2014-01-01

In light of ocean warming and loss of Arctic sea ice, harvested marine fishes of boreal origin (and their fisheries) move poleward into yet unexploited parts of the Arctic seas. Industrial fisheries, already in place on many Arctic shelves, will radically affect the local fish species as they turn up as unprecedented bycatch. Arctic marine fishes are indispensable to ecosystem structuring and functioning, but they are still beyond credible assessment due to lack of basic biological data. The time for conservation actions is now, and precautionary management practices by the Arctic coastal states are needed to mitigate the impact of industrial fisheries in Arctic waters. We outline four possible conservation actions: scientific credibility, ‘green technology’, legitimate management and overarching coordination. PMID:24105993

Eukaryotic Life Inhabits Rhodolith-forming Coralline Algae (Hapalidiales, Rhodophyta), Remarkable Marine Benthic Microhabitats

PubMed Central

Krayesky-Self, Sherry; Schmidt, William E.; Phung, Delena; Henry, Caroline; Sauvage, Thomas; Camacho, Olga; Felgenhauer, Bruce E.; Fredericq, Suzanne

2017-01-01

Rhodoliths are benthic calcium carbonate nodules accreted by crustose coralline red algae which recently have been identified as useful indicators of biomineral changes resulting from global climate change and ocean acidification. This study highlights the discovery that the interior of rhodoliths are marine biodiversity hotspots that function as seedbanks and temporary reservoirs of previously unknown stages in the life history of ecologically important dinoflagellate and haptophyte microalgae. Whereas the studied rhodoliths originated from offshore deep bank pinnacles in the northwestern Gulf of Mexico, the present study opens the door to assess the universality of endolithic stages among bloom-forming microalgae spanning different phyla, some of public health concerns (Prorocentrum) in marine ecosystems worldwide. PMID:28368049

Exploring Actinobacteria assemblages in coastal marine sediments under contrasted Human influences in the West Istria Sea, Croatia.

PubMed

Duran, Robert; Bielen, Ana; Paradžik, Tina; Gassie, Claire; Pustijanac, Emina; Cagnon, Christine; Hamer, Bojan; Vujaklija, Dušica

2015-10-01

The exploration of marine Actinobacteria has as major challenge to answer basic questions of microbial ecology that, in turn, will provide useful information to exploit Actinobacteria metabolisms in biotechnological processes. The ecological functions performed by Actinobacteria in marine sediments are still unclear and belongs to the most burning basic questions. The comparison of Actinobacteria communities inhabiting marine sediments that are under the influence of different contamination types will provide valuable information in the adaptation capacities of Actinobacteria to colonize specific ecological niche. In the present study, the characterization of different Actinobacteria assemblages according to contamination type revealed the ecological importance of Actinobacteria for maintaining both general biogeochemical functions through a "core" Actinobacteria community and specific roles associated with the presence of contaminants. Indeed, the results allowed to distinguish Actinobacteria genera and species operational taxonomic units (OTUs) able to cope with the presence of either (i) As, (ii) metals Ni, Fe, V, Cr, and Mn, or (iii) polycyclic aromatic hydrocarbons (PAHs) and toxic metals (Hg, Cd, Cu, Pb, and Zn). Such observations highlighted the metabolic capacities of Actinobacteria and their potential that should be taken into consideration and advantage during the implementation of bioremediation processes in marine ecosystems.

Metal-Macrofauna Interactions Determine Microbial Community Structure and Function in Copper Contaminated Sediments

PubMed Central

Mayor, Daniel J.; Gray, Nia B.; Elver-Evans, Joanna; Midwood, Andrew J.; Thornton, Barry

2013-01-01

Copper is essential for healthy cellular functioning, but this heavy metal quickly becomes toxic when supply exceeds demand. Marine sediments receive widespread and increasing levels of copper contamination from antifouling paints owing to the 2008 global ban of organotin-based products. The toxicity of copper will increase in the coming years as seawater pH decreases and temperature increases. We used a factorial mesocosm experiment to investigate how increasing sediment copper concentrations and the presence of a cosmopolitan bioturbating amphipod, Corophium volutator, affected a range of ecosystem functions in a soft sediment microbial community. The effects of copper on benthic nutrient release, bacterial biomass, microbial community structure and the isotopic composition of individual microbial membrane [phospholipid] fatty acids (PLFAs) all differed in the presence of C. volutator. Our data consistently demonstrate that copper contamination of global waterways will have pervasive effects on the metabolic functioning of benthic communities that cannot be predicted from copper concentrations alone; impacts will depend upon the resident macrofauna and their capacity for bioturbation. This finding poses a major challenge for those attempting to manage the impacts of copper contamination on ecosystem services, e.g. carbon and nutrient cycling, across different habitats. Our work also highlights the paucity of information on the processes that result in isotopic fractionation in natural marine microbial communities. We conclude that the assimilative capacity of benthic microbes will become progressively impaired as copper concentrations increase. These effects will, to an extent, be mitigated by the presence of bioturbating animals and possibly other processes that increase the influx of oxygenated seawater into the sediments. Our findings support the move towards an ecosystem approach for environmental management. PMID:23741430

Metal-macrofauna interactions determine microbial community structure and function in copper contaminated sediments.

PubMed

Mayor, Daniel J; Gray, Nia B; Elver-Evans, Joanna; Midwood, Andrew J; Thornton, Barry

2013-01-01

Copper is essential for healthy cellular functioning, but this heavy metal quickly becomes toxic when supply exceeds demand. Marine sediments receive widespread and increasing levels of copper contamination from antifouling paints owing to the 2008 global ban of organotin-based products. The toxicity of copper will increase in the coming years as seawater pH decreases and temperature increases. We used a factorial mesocosm experiment to investigate how increasing sediment copper concentrations and the presence of a cosmopolitan bioturbating amphipod, Corophium volutator, affected a range of ecosystem functions in a soft sediment microbial community. The effects of copper on benthic nutrient release, bacterial biomass, microbial community structure and the isotopic composition of individual microbial membrane [phospholipid] fatty acids (PLFAs) all differed in the presence of C. volutator. Our data consistently demonstrate that copper contamination of global waterways will have pervasive effects on the metabolic functioning of benthic communities that cannot be predicted from copper concentrations alone; impacts will depend upon the resident macrofauna and their capacity for bioturbation. This finding poses a major challenge for those attempting to manage the impacts of copper contamination on ecosystem services, e.g. carbon and nutrient cycling, across different habitats. Our work also highlights the paucity of information on the processes that result in isotopic fractionation in natural marine microbial communities. We conclude that the assimilative capacity of benthic microbes will become progressively impaired as copper concentrations increase. These effects will, to an extent, be mitigated by the presence of bioturbating animals and possibly other processes that increase the influx of oxygenated seawater into the sediments. Our findings support the move towards an ecosystem approach for environmental management.

An inventory and monitoring plan for a Sonoran Desert ecosystem; Barry M. Goldwater Range-West

USGS Publications Warehouse

Villarreal, Miguel L.; van Riper, Charles; Lovich, Robert E.; Palmer, Robert L.; Nauman, Travis; Studd, Sarah E.; Drake, Sam; Rosenberg, Abigail S.; Malusa, Jim; Pearce, Ronald L.

2011-01-01

Marine Corps Air Station Yuma manages the Barry M. Goldwater Range-West, which encompasses approximately 2,800 square kilometers of Sonoran Desert habitat in southwestern Arizona. The Barry M. Goldwater Range is a major U.S. military installation designed as an air combat training location for the U.S. Marine Corps and U.S. Air Force, but it also includes some of the most pristine desert habitat in the United States. In an effort to ensure the long-term viability of this unique natural resource, the U.S. Geological Survey (USGS) has developed an Integrated Natural Resources Management Plan and Inventory and Monitoring Plan to guide natural resource management of the Barry M. Goldwater Range-West. This Inventory and Monitoring Plan provides a framework for long-term ecosystem monitoring on Barry M. Goldwater Range-West lands by identifying existing and potential threats to ecosystem function, prioritizing resources for monitoring, and providing information and protocols necessary to initiate a long-term ecosystem monitoring program. The Inventory and Monitoring Plan and related protocols were developed through extensive review of existing Sonoran Desert monitoring programs and monitoring literature and through a 2-day workshop with resource managers, monitoring experts, and other stakeholders. The Barry M. Goldwater Range-West Inventory and Monitoring Plan stresses the importance of regional monitoring partnerships and protocol standardization for understanding landscape-scale ecosystem changes in the Sonoran Desert; information and protocols contained within the plan may also be of interest to land managers engaged in large-scale ecosystem monitoring and adaptive management of other arid regions.

Aerosols in atmospheric chemistry and biogeochemical cycles of nutrients

NASA Astrophysics Data System (ADS)

Kanakidou, Maria; Myriokefalitakis, Stelios; Tsigaridis, Kostas

2018-06-01

Atmospheric aerosols have complex and variable compositions and properties. While scientific interest is centered on the health and climatic effects of atmospheric aerosols, insufficient attention is given to their involvement in multiphase chemistry that alters their contribution as carriers of nutrients in ecosystems. However, there is experimental proof that the nutrient equilibria of both land and marine ecosystems have been disturbed during the Anthropocene period. This review study first summarizes our current understanding of aerosol chemical processing in the atmosphere as relevant to biogeochemical cycles. Then it binds together results of recent modeling studies based on laboratory and field experiments, focusing on the organic and dust components of aerosols that account for multiphase chemistry, aerosol ageing in the atmosphere, nutrient (N, P, Fe) emissions, atmospheric transport, transformation and deposition. The human-driven contribution to atmospheric deposition of these nutrients, derived by global simulations using past and future anthropogenic emissions of pollutants, is put into perspective with regard to potential changes in nutrient limitations and biodiversity. Atmospheric deposition of nutrients has been suggested to result in human-induced ecosystem limitations with regard to specific nutrients. Such modifications favor the development of certain species against others and affect the overall functioning of ecosystems. Organic forms of nutrients are found to contribute to the atmospheric deposition of the nutrients N, P and Fe by 20%–40%, 35%–45% and 7%–18%, respectively. These have the potential to be key components of the biogeochemical cycles since there is initial proof of their bioavailability to ecosystems. Bioaerosols have been found to make a significant contribution to atmospheric sources of N and P, indicating potentially significant interactions between terrestrial and marine ecosystems. These results deserve further experimental and modeling studies to reduce uncertainties and understand the feedbacks induced by atmospheric deposition of nutrients to ecosystems.

Trophic downgrading of planet Earth.

PubMed

Estes, James A; Terborgh, John; Brashares, Justin S; Power, Mary E; Berger, Joel; Bond, William J; Carpenter, Stephen R; Essington, Timothy E; Holt, Robert D; Jackson, Jeremy B C; Marquis, Robert J; Oksanen, Lauri; Oksanen, Tarja; Paine, Robert T; Pikitch, Ellen K; Ripple, William J; Sandin, Stuart A; Scheffer, Marten; Schoener, Thomas W; Shurin, Jonathan B; Sinclair, Anthony R E; Soulé, Michael E; Virtanen, Risto; Wardle, David A

2011-07-15

Until recently, large apex consumers were ubiquitous across the globe and had been for millions of years. The loss of these animals may be humankind's most pervasive influence on nature. Although such losses are widely viewed as an ethical and aesthetic problem, recent research reveals extensive cascading effects of their disappearance in marine, terrestrial, and freshwater ecosystems worldwide. This empirical work supports long-standing theory about the role of top-down forcing in ecosystems but also highlights the unanticipated impacts of trophic cascades on processes as diverse as the dynamics of disease, wildfire, carbon sequestration, invasive species, and biogeochemical cycles. These findings emphasize the urgent need for interdisciplinary research to forecast the effects of trophic downgrading on process, function, and resilience in global ecosystems.

Influence of dimethyl sulfide on the carbon cycle and biological production

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Shanlin; Maltrud, Mathew; Elliott, Scott

Dimethyl sulfide (DMS) is a significant source of marine sulfate aerosol and plays an important role in modifying cloud properties. Fully coupled climate simulations using dynamic marine ecosystem and DMS calculations are conducted to estimate DMS fluxes under various climate scenarios and to examine the sign and strength of phytoplankton-DMS-climate feedbacks for the first time. Simulation results show small differences in the DMS production and emissions between pre-industrial and present climate scenarios, except for some areas in the Southern Ocean. There are clear changes in surface ocean DMS concentrations moving into the future, and they are attributable to changes inmore » phytoplankton production and competition driven by complex spatially varying mechanisms. Comparisons between parallel simulations with and without DMS fluxes into the atmosphere show significant differences in marine ecosystems and physical fields. Without DMS, the missing subsequent aerosol indirect effects on clouds and radiative forcing lead to fewer clouds, more solar radiation, and a much warmer climate. Phaeocystis, a uniquely efficient organosulfur producer with a growth advantage under cooler climate states, can benefit from producing the compound through cooling effects of DMS in the climate system. Our results show a tight coupling between the sulfur and carbon cycles. The ocean carbon uptake declines without DMS emissions to the atmosphere. The analysis indicates a weak positive phytoplankton-DMS-climate feedback at the global scale, with large spatial variations driven by individual autotrophic functional groups and complex mechanisms. The sign and strength of the feedback vary with climate states and phytoplankton groups. This highlights the importance of a dynamic marine ecosystem module and the sulfur cycle mechanism in climate projections.« less

High-density polyethylene (HDPE)-degrading potential bacteria from marine ecosystem of Gulf of Mannar, India.

PubMed

Balasubramanian, V; Natarajan, K; Hemambika, B; Ramesh, N; Sumathi, C S; Kottaimuthu, R; Rajesh Kannan, V

2010-08-01

Assessment of high-density polyethylene (HDPE)-degrading bacteria isolated from plastic waste dumpsites of Gulf of Mannar. Rationally, 15 bacteria (GMB1-GMB15) were isolated by enrichment technique. GMB5 and GMB7 were selected for further studies based on their efficiency to degrade the HDPE and identified as Arthrobacter sp. and Pseudomonas sp., respectively. Assessed weight loss of HDPE after 30 days of incubation was nearly 12% for Arthrobacter sp. and 15% for Pseudomonas sp. The bacterial adhesion to hydrocarbon (BATH) assay showed that the cell surface hydrophobicity of Pseudomonas sp. was higher than Arthrobacter sp. Both fluorescein diacetate hydrolysis and protein content of the biofilm were used to test the viability and protein density of the biomass. Acute peak elevation was observed between 2 and 5 days of inoculation for both bacteria. Fourier transform infrared (FT-IR) spectrum showed that keto carbonyl bond index (KCBI), Ester carbonyl bond index (ECBI) and Vinyl bond index (VBI) were increased indicating changes in functional group(s) and/or side chain modification confirming the biodegradation. The results pose us to suggest that both Pseudomonas sp. and Arthrobacter sp. were proven efficient to degrade HDPE, albeit the former was more efficacious, yet the ability of latter cannot be neglected. Recent alarm on ecological threats to marine system is dumping plastic waste in the marine ecosystem and coastal arena by anthropogenic activity. In maintenance phase of the plastic-derived polyethylene waste, the microbial degradation plays a major role; the information accomplished in this work will be the initiating point for the degradation of polyethylene by indigenous bacterial population in the marine ecosystem and provides a novel eco-friendly solution in eco-management.

Influence of dimethyl sulfide on the carbon cycle and biological production

DOE PAGES

Wang, Shanlin; Maltrud, Mathew; Elliott, Scott; ...

2018-02-27

Dimethyl sulfide (DMS) is a significant source of marine sulfate aerosol and plays an important role in modifying cloud properties. Fully coupled climate simulations using dynamic marine ecosystem and DMS calculations are conducted to estimate DMS fluxes under various climate scenarios and to examine the sign and strength of phytoplankton-DMS-climate feedbacks for the first time. Simulation results show small differences in the DMS production and emissions between pre-industrial and present climate scenarios, except for some areas in the Southern Ocean. There are clear changes in surface ocean DMS concentrations moving into the future, and they are attributable to changes inmore » phytoplankton production and competition driven by complex spatially varying mechanisms. Comparisons between parallel simulations with and without DMS fluxes into the atmosphere show significant differences in marine ecosystems and physical fields. Without DMS, the missing subsequent aerosol indirect effects on clouds and radiative forcing lead to fewer clouds, more solar radiation, and a much warmer climate. Phaeocystis, a uniquely efficient organosulfur producer with a growth advantage under cooler climate states, can benefit from producing the compound through cooling effects of DMS in the climate system. Our results show a tight coupling between the sulfur and carbon cycles. The ocean carbon uptake declines without DMS emissions to the atmosphere. The analysis indicates a weak positive phytoplankton-DMS-climate feedback at the global scale, with large spatial variations driven by individual autotrophic functional groups and complex mechanisms. The sign and strength of the feedback vary with climate states and phytoplankton groups. This highlights the importance of a dynamic marine ecosystem module and the sulfur cycle mechanism in climate projections.« less

Formulation, General Features and Global Calibration of a Bioenergetically-Constrained Fishery Model

PubMed Central

Bianchi, Daniele; Galbraith, Eric D.

2017-01-01

Human exploitation of marine resources is profoundly altering marine ecosystems, while climate change is expected to further impact commercially-harvested fish and other species. Although the global fishery is a highly complex system with many unpredictable aspects, the bioenergetic limits on fish production and the response of fishing effort to profit are both relatively tractable, and are sure to play important roles. Here we describe a generalized, coupled biological-economic model of the global marine fishery that represents both of these aspects in a unified framework, the BiOeconomic mArine Trophic Size-spectrum (BOATS) model. BOATS predicts fish production according to size spectra as a function of net primary production and temperature, and dynamically determines harvest spectra from the biomass density and interactive, prognostic fishing effort. Within this framework, the equilibrium fish biomass is determined by the economic forcings of catchability, ex-vessel price and cost per unit effort, while the peak harvest depends on the ecosystem parameters. Comparison of a large ensemble of idealized simulations with observational databases, focusing on historical biomass and peak harvests, allows us to narrow the range of several uncertain ecosystem parameters, rule out most parameter combinations, and select an optimal ensemble of model variants. Compared to the prior distributions, model variants with lower values of the mortality rate, trophic efficiency, and allometric constant agree better with observations. For most acceptable parameter combinations, natural mortality rates are more strongly affected by temperature than growth rates, suggesting different sensitivities of these processes to climate change. These results highlight the utility of adopting large-scale, aggregated data constraints to reduce model parameter uncertainties and to better predict the response of fisheries to human behaviour and climate change. PMID:28103280

Formulation, General Features and Global Calibration of a Bioenergetically-Constrained Fishery Model.

PubMed

Carozza, David A; Bianchi, Daniele; Galbraith, Eric D

2017-01-01

Human exploitation of marine resources is profoundly altering marine ecosystems, while climate change is expected to further impact commercially-harvested fish and other species. Although the global fishery is a highly complex system with many unpredictable aspects, the bioenergetic limits on fish production and the response of fishing effort to profit are both relatively tractable, and are sure to play important roles. Here we describe a generalized, coupled biological-economic model of the global marine fishery that represents both of these aspects in a unified framework, the BiOeconomic mArine Trophic Size-spectrum (BOATS) model. BOATS predicts fish production according to size spectra as a function of net primary production and temperature, and dynamically determines harvest spectra from the biomass density and interactive, prognostic fishing effort. Within this framework, the equilibrium fish biomass is determined by the economic forcings of catchability, ex-vessel price and cost per unit effort, while the peak harvest depends on the ecosystem parameters. Comparison of a large ensemble of idealized simulations with observational databases, focusing on historical biomass and peak harvests, allows us to narrow the range of several uncertain ecosystem parameters, rule out most parameter combinations, and select an optimal ensemble of model variants. Compared to the prior distributions, model variants with lower values of the mortality rate, trophic efficiency, and allometric constant agree better with observations. For most acceptable parameter combinations, natural mortality rates are more strongly affected by temperature than growth rates, suggesting different sensitivities of these processes to climate change. These results highlight the utility of adopting large-scale, aggregated data constraints to reduce model parameter uncertainties and to better predict the response of fisheries to human behaviour and climate change.

Marine mollusc predator-escape behaviour altered by near-future carbon dioxide levels

PubMed Central

Watson, Sue-Ann; Lefevre, Sjannie; McCormick, Mark I.; Domenici, Paolo; Nilsson, Göran E.; Munday, Philip L.

2014-01-01

Ocean acidification poses a range of threats to marine invertebrates; however, the potential effects of rising carbon dioxide (CO2) on marine invertebrate behaviour are largely unknown. Marine gastropod conch snails have a modified foot and operculum allowing them to leap backwards rapidly when faced with a predator, such as a venomous cone shell. Here, we show that projected near-future seawater CO2 levels (961 µatm) impair this escape behaviour during a predator–prey interaction. Elevated-CO2 halved the number of snails that jumped from the predator, increased their latency to jump and altered their escape trajectory. Physical ability to jump was not affected by elevated-CO2 indicating instead that decision-making was impaired. Antipredator behaviour was fully restored by treatment with gabazine, a GABA antagonist of some invertebrate nervous systems, indicating potential interference of neurotransmitter receptor function by elevated-CO2, as previously observed in marine fishes. Altered behaviour of marine invertebrates at projected future CO2 levels could have potentially far-reaching implications for marine ecosystems. PMID:24225456

Carbon utilization profile of the filamentous fungal species Fusarium fujikuroi, Penicillium decumbens, and Sarocladium strictum isolated from marine coastal environments.

PubMed

Fuentes, Marcelo E; Quiñones, Renato A

Facultative marine filamentous fungi have recently emerged as a functional component in coastal marine systems. However, little is known about their ecological role and functions in biogeochemical cycles. Penicillium decumbens, S. strictum, and F. fujikuroi were isolated from the coastal upwelling zone off south-central Chile. Their carbon profiles were characterized using Biolog FF MicroPlates. These species used a wide range of carbon sources, mainly carbohydrates, but also amino acids, suggesting the use of metabolic routes that include glycolysis/gluconeogenesis. Substrate richness revealed a great capacity for the utilization of nutritional sources, reflected by the following Shannon Indices of utilization of specific substrates: 4.02 for S. strictum, 4.01 for P. decumbes, and 3.91 for F. fujikuroi, which reveals a high physiological capacity for oxidizing different substrates. Significant differences were found between 18 substrates utilized by all three species. Results suggest that filamentous fungi should be considered an integral part of the marine microbial community and included in biogeochemical cycling models of upwelling ecosystems.

Bivalve Omics: State of the Art and Potential Applications for the Biomonitoring of Harmful Marine Compounds

PubMed Central

Suárez-Ulloa, Victoria; Fernández-Tajes, Juan; Manfrin, Chiara; Gerdol, Marco; Venier, Paola; Eirín-López, José M.

2013-01-01

The extraordinary progress experienced by sequencing technologies and bioinformatics has made the development of omic studies virtually ubiquitous in all fields of life sciences nowadays. However, scientific attention has been quite unevenly distributed throughout the different branches of the tree of life, leaving molluscs, one of the most diverse animal groups, relatively unexplored and without representation within the narrow collection of well established model organisms. Within this Phylum, bivalve molluscs play a fundamental role in the functioning of the marine ecosystem, constitute very valuable commercial resources in aquaculture, and have been widely used as sentinel organisms in the biomonitoring of marine pollution. Yet, it has only been very recently that this complex group of organisms became a preferential subject for omic studies, posing new challenges for their integrative characterization. The present contribution aims to give a detailed insight into the state of the art of the omic studies and functional information analysis of bivalve molluscs, providing a timely perspective on the available data resources and on the current and prospective applications for the biomonitoring of harmful marine compounds. PMID:24189277

Ecological and evolutionary genomics of marine photosynthetic organisms.

PubMed

Coelho, Susana M; Simon, Nathalie; Ahmed, Sophia; Cock, J Mark; Partensky, Frédéric

2013-02-01

Environmental (ecological) genomics aims to understand the genetic basis of relationships between organisms and their abiotic and biotic environments. It is a rapidly progressing field of research largely due to recent advances in the speed and volume of genomic data being produced by next generation sequencing (NGS) technologies. Building on information generated by NGS-based approaches, functional genomic methodologies are being applied to identify and characterize genes and gene systems of both environmental and evolutionary relevance. Marine photosynthetic organisms (MPOs) were poorly represented amongst the early genomic models, but this situation is changing rapidly. Here we provide an overview of the recent advances in the application of ecological genomic approaches to both prokaryotic and eukaryotic MPOs. We describe how these approaches are being used to explore the biology and ecology of marine cyanobacteria and algae, particularly with regard to their functions in a broad range of marine ecosystems. Specifically, we review the ecological and evolutionary insights gained from whole genome and transcriptome sequencing projects applied to MPOs and illustrate how their genomes are yielding information on the specific features of these organisms. © 2012 Blackwell Publishing Ltd.

Methylmercury in Marine Ecosystems: From Sources to Seafood Consumers -- A Work Group Report

EPA Science Inventory

Consumption of marine fish and shellfish is a major route of human exposure to methyl mercury. This paper is the result of a workshop by the Dartmouth Toxic Metals Research Program in November 2006 on "Fate and Bioavailability of Mercury in Aquatic Ecosystems and Effects on Human...

St. Petersburg Coastal and Marine Science Center coral reef research

USGS Publications Warehouse

Poore, Richard Z.; Kuffner, Ilsa B.; Kellogg, Christina A.

2010-01-01

The U.S. Geological Survey (USGS) Coral Reef Ecosystem STudies (CREST) Project specifically addresses priorities identified in the 'Facing tomorrow's challenges' U.S. Geological Survey science in the decade 2007-2017' document (USGS, 2007). Research includes a blend of historical, monitoring, and process studies aimed at improving our understanding of the development, current status and function, as well as likely future changes in coral ecosystems. Topics such as habitat characterization and distribution, coral disease, and trends in biogenic calcification are major focus areas. We seek to increase the understanding of reef structure, ecological integrity, and responses to global change.

GLOBEC: Global Ocean Ecosystems Dynamics: A component of the US Global Change Research Program

NASA Technical Reports Server (NTRS)

1991-01-01

GLOBEC (GLOBal ocean ECosystems dynamics) is a research initiative proposed by the oceanographic and fisheries communities to address the question of how changes in global environment are expected to affect the abundance and production of animals in the sea. The approach to this problem is to develop a fundamental understanding of the mechanisms that determine both the abundance of key marine animal populations and their variances in space and time. The assumption is that the physical environment is a major contributor to patterns of abundance and production of marine animals, in large part because the planktonic life stages typical of most marine animals are intrinsically at the mercy of the fluid motions of the medium in which they live. Consequently, the authors reason that a logical approach to predicting the potential impact of a globally changing environment is to understand how the physical environment, both directly and indirectly, contributes to animal abundance and its variability in marine ecosystems. The plans for this coordinated study of of the potential impact of global change on ocean ecosystems dynamics are discussed.

Integrated network modelling for identifying microbial mechanisms of particulate organic carbon accumulation in coastal marine systems

NASA Astrophysics Data System (ADS)

McDonald, Karlie; Turk, Valentina; Mozetič, Patricija; Tinta, Tinkara; Malfatti, Francesca; Hannah, David; Krause, Stefan

2016-04-01

Accumulation of particulate organic carbon (POC) has the potential to change the structure and function of marine ecosystems. High abidance of POC can develop into aggregates, known as marine snow or mucus aggregates that can impair essential marine ecosystem functioning and services. Currently marine POC formation, accumulation and sedimentation processes are being explored as potential pathways to remove CO2 from the atmosphere by CO2 sequestration via fixation into biomass by phytoplankton. However, the current ability of scientists, environmental managers and regulators to analyse and predict high POC concentrations is restricted by the limited understanding of the dynamic nature of the microbial mechanisms regulating POC accumulation events in marine environments. We present a proof of concept study that applies a novel Bayesian Networks (BN) approach to integrate relevant biological and physical-chemical variables across spatial and temporal scales in order to identify the interactions of the main contributing microbial mechanisms regulating POC accumulation in the northern Adriatic Sea. Where previous models have characterised only the POC formed, the BN approach provides a probabilistic framework for predicting the occurrence of POC accumulation by linking biotic factors with prevailing environmental conditions. In this paper the BN was used to test three scenarios (diatom, nanoflagellate, and dinoflagellate blooms). The scenarios predicted diatom blooms to produce high chlorophyll a at the water surface while nanoflagellate blooms were predicted to occur at lower depths (> 6m) in the water column and produce lower chlorophyll a concentrations. A sensitivity analysis identified the variables with the greatest influence on POC accumulation being the enzymes protease and alkaline phosphatase, which highlights the importance of microbial community interactions. The developed proof of concept BN model allows for the first time to quantify the impacts of biological, chemical and physical parameters influencing microbial community interactions mechanisms that regulate POC accumulation in marine environments. The dynamic modular nature of the developed BN will allow successive updating and improvement of the model structure as new data are emerging, thus, providing a powerful interactive framework for the investigation, prediction and mitigation of future POC accumulation events.

Cumulative human impacts on marine predators.

PubMed

Maxwell, Sara M; Hazen, Elliott L; Bograd, Steven J; Halpern, Benjamin S; Breed, Greg A; Nickel, Barry; Teutschel, Nicole M; Crowder, Larry B; Benson, Scott; Dutton, Peter H; Bailey, Helen; Kappes, Michelle A; Kuhn, Carey E; Weise, Michael J; Mate, Bruce; Shaffer, Scott A; Hassrick, Jason L; Henry, Robert W; Irvine, Ladd; McDonald, Birgitte I; Robinson, Patrick W; Block, Barbara A; Costa, Daniel P

2013-01-01

Stressors associated with human activities interact in complex ways to affect marine ecosystems, yet we lack spatially explicit assessments of cumulative impacts on ecologically and economically key components such as marine predators. Here we develop a metric of cumulative utilization and impact (CUI) on marine predators by combining electronic tracking data of eight protected predator species (n=685 individuals) in the California Current Ecosystem with data on 24 anthropogenic stressors. We show significant variation in CUI with some of the highest impacts within US National Marine Sanctuaries. High variation in underlying species and cumulative impact distributions means that neither alone is sufficient for effective spatial management. Instead, comprehensive management approaches accounting for both cumulative human impacts and trade-offs among multiple stressors must be applied in planning the use of marine resources.

Biodiversity's Big Wet Secret: The Global Distribution of Marine Biological Records Reveals Chronic Under-Exploration of the Deep Pelagic Ocean

PubMed Central

Webb, Thomas J.; Vanden Berghe, Edward; O'Dor, Ron

2010-01-01

Background Understanding the distribution of marine biodiversity is a crucial first step towards the effective and sustainable management of marine ecosystems. Recent efforts to collate location records from marine surveys enable us to assemble a global picture of recorded marine biodiversity. They also effectively highlight gaps in our knowledge of particular marine regions. In particular, the deep pelagic ocean – the largest biome on Earth – is chronically under-represented in global databases of marine biodiversity. Methodology/Principal Findings We use data from the Ocean Biogeographic Information System to plot the position in the water column of ca 7 million records of marine species occurrences. Records from relatively shallow waters dominate this global picture of recorded marine biodiversity. In addition, standardising the number of records from regions of the ocean differing in depth reveals that regardless of ocean depth, most records come either from surface waters or the sea bed. Midwater biodiversity is drastically under-represented. Conclusions/Significance The deep pelagic ocean is the largest habitat by volume on Earth, yet it remains biodiversity's big wet secret, as it is hugely under-represented in global databases of marine biological records. Given both its value in the provision of a range of ecosystem services, and its vulnerability to threats including overfishing and climate change, there is a pressing need to increase our knowledge of Earth's largest ecosystem. PMID:20689845

A bottom-up perspective on ecosystem change in Mesozoic oceans

PubMed Central

Follows, Michael J.

2016-01-01

Mesozoic and Early Cenozoic marine animals across multiple phyla record secular trends in morphology, environmental distribution, and inferred behaviour that are parsimoniously explained in terms of increased selection pressure from durophagous predators. Another systemic change in Mesozoic marine ecosystems, less widely appreciated than the first, may help to explain the observed animal record. Fossils, biomarker molecules, and molecular clocks indicate a major shift in phytoplankton composition, as mixotrophic dinoflagellates, coccolithophorids and, later, diatoms radiated across shelves. Models originally developed to probe the ecology and biogeography of modern phytoplankton enable us to evaluate the ecosystem consequences of these phytoplankton radiations. In particular, our models suggest that the radiation of mixotrophic dinoflagellates and the subsequent diversification of marine diatoms would have accelerated the transfer of primary production upward into larger size classes and higher trophic levels. Thus, phytoplankton evolution provides a mechanism capable of facilitating the observed evolutionary shift in Mesozoic marine animals. PMID:27798303

A bottom-up perspective on ecosystem change in Mesozoic oceans.

PubMed

Knoll, Andrew H; Follows, Michael J

2016-10-26

Mesozoic and Early Cenozoic marine animals across multiple phyla record secular trends in morphology, environmental distribution, and inferred behaviour that are parsimoniously explained in terms of increased selection pressure from durophagous predators. Another systemic change in Mesozoic marine ecosystems, less widely appreciated than the first, may help to explain the observed animal record. Fossils, biomarker molecules, and molecular clocks indicate a major shift in phytoplankton composition, as mixotrophic dinoflagellates, coccolithophorids and, later, diatoms radiated across shelves. Models originally developed to probe the ecology and biogeography of modern phytoplankton enable us to evaluate the ecosystem consequences of these phytoplankton radiations. In particular, our models suggest that the radiation of mixotrophic dinoflagellates and the subsequent diversification of marine diatoms would have accelerated the transfer of primary production upward into larger size classes and higher trophic levels. Thus, phytoplankton evolution provides a mechanism capable of facilitating the observed evolutionary shift in Mesozoic marine animals. © 2016 The Authors.

Manatees as sentinels of marine ecosystem health: are they the 2000-pound canaries?

USGS Publications Warehouse

Bonde, R.K.; Aguirre, A.A.; Powell, J.

2004-01-01

The order Sirenia is represented by three species of manatees and one species of dugong distributed in tropical and subtropical regions of the world and considered vulnerable to extinction. The sentinel species concept is useful to identify indicators of the environment and may reflect the quality of health in marine ecosystems. The single species approach to evaluate ecological health may provide a series of “snap shots” of environmental changes to determine if animal, human, or ecosystem health may be affected. Under this concept, marine vertebrates may be good integrators of changes over space and time, and excellent sentinels of ecosystem health. Based on their life history, manatees may or may not be ideal sentinels, as they are robust, long-lived species and appear remarkably resilient to natural disease and the effects of human-related injury and trauma. These characteristics might be the result of an efficient and responsive immune system compared to other marine mammals. Although relatively immune to infectious agents, manatees face other potentially serious threats, including epizootic diseases and pollution while in large aggregations. Manatees can serve as excellent sentinels of harmful algal blooms due to their high sensitivity, specifically to brevetoxicosis, which has caused at least two major die-offs in recent times. Threats to manatees worldwide, such as illegal hunting and boat collisions, are increasing. Habitat is being lost at an alarming rate and the full effects of uncontrolled human population growth on the species are unknown. The manatee may serve as a sentinel species, prognosticating the deleterious effects of unhealthy marine and aquatic ecosystems on humans. We have identified a number of critical research needs and opportunities for transdisciplinary collaboration that could help advance the use of the sentinel species concept in marine ecosystem health and monitoring of disease emergence using our knowledge on these magnificent sirenians.

A fish is not a fish: patterns in fatty acid composition of aquatic food may have had implications for hominin evolution.

PubMed

Joordens, Josephine C A; Kuipers, Remko S; Wanink, Jan H; Muskiet, Frits A J

2014-12-01

From c. 2 Ma (millions of years ago) onwards, hominin brain size and cognition increased in an unprecedented fashion. The exploitation of high-quality food resources, notably from aquatic ecosystems, may have been a facilitator or driver of this phenomenon. The aim of this study is to contribute to the ongoing debate on the possible role of aquatic resources in hominin evolution by providing a more detailed nutritional context. So far, the debate has focused on the relative importance of terrestrial versus aquatic resources while no distinction has been made between different types of aquatic resources. Here we show that Indian Ocean reef fish and eastern African lake fish yield on average similarly high amounts of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid (AA). Hence a shift from exploiting tropical marine to freshwater ecosystems (or vice versa) would entail no material difference in dietary long-chain polyunsaturated fatty acid (LC-PUFA) availability. However, a shift to marine ecosystems would likely mean a major increase in access to brain-selective micronutrients such as iodine. Fatty fish from marine temperate/cold waters yield twice as much DHA and four times as much EPA as tropical fish, demonstrating that a latitudinal shift in exploitation of African coastal ecosystems could constitute a significant difference in LC-PUFA availability with possible implications for brain development and functioning. We conclude that exploitation of aquatic food resources could have facilitated the initial moderate hominin brain increase as observed in fossils dated to c. 2 Ma, but not the exceptional brain increase in later stages of hominin evolution. We propose that the significant expansion in hominin brain size and cognition later on may have been aided by strong directional selecting forces such as runaway sexual selection of intelligence, and nutritionally supported by exploitation of high-quality food resources in stable and productive aquatic ecosystems. Copyright © 2014 Elsevier Ltd. All rights reserved.

Climatic vulnerability of the world’s freshwater and marine fishes

NASA Astrophysics Data System (ADS)

Comte, Lise; Olden, Julian D.

2017-10-01

Climate change is a mounting threat to biological diversity, compromising ecosystem structure and function, and undermining the delivery of essential services worldwide. As the magnitude and speed of climate change accelerates, greater understanding of the taxonomy and geography of climatic vulnerability is critical to guide effective conservation action. However, many uncertainties remain regarding the degree and variability of climatic risk within entire clades and across vast ecosystem boundaries. Here we integrate physiological estimates of thermal sensitivity for 2,960 ray-finned fishes with future climatic exposure, and demonstrate that global patterns of vulnerability differ substantially between freshwater and marine realms. Our results suggest that climatic vulnerability for freshwater faunas will be predominantly determined by elevated levels of climatic exposure predicted for the Northern Hemisphere, whereas marine faunas in the tropics will be the most at risk, reflecting their higher intrinsic sensitivity. Spatial overlap between areas of high physiological risk and high human impacts, together with evidence of low past rates of evolution in upper thermal tolerance, highlights the urgency of global conservation actions and policy initiatives if harmful climate effects on the world’s fishes are to be mitigated in the future.

A Hierarchical and Dynamic Seascape Framework for Scaling and Comparing Ocean Biodiversity Observations

NASA Astrophysics Data System (ADS)

Kavanaugh, M.; Muller-Karger, F. E.; Montes, E.; Santora, J. A.; Chavez, F.; Messié, M.; Doney, S. C.

2016-02-01

The pelagic ocean is a complex system in which physical, chemical and biological processes interact to shape patterns on multiple spatial and temporal scales and levels of ecological organization. Monitoring and management of marine seascapes must consider a hierarchical and dynamic mosaic, where the boundaries, extent, and location of features change with time. As part of a Marine Biodiversity Observing Network demonstration project, we conducted a multiscale classification of dynamic coastal seascapes in the northeastern Pacific and Gulf of Mexico using multivariate satellite and modeled data. Synoptic patterns were validated using mooring and ship-based observations that spanned multiple trophic levels and were collected as part of several long-term monitoring programs, including the Monterey Bay and Florida Keys National Marine Sanctuaries. Seascape extent and habitat diversity varied as a function of both seasonal and interannual forcing. We discuss the patterns of in situ observations in the context of seascape dynamics and the effect on rarefaction, spatial patchiness, and tracking and comparing ecosystems through time. A seascape framework presents an effective means to translate local biodiversity measurements to broader spatiotemporal scales, scales relevant for modeling the effects of global change and enabling whole-ecosystem management in the dynamic ocean.

Squid as nutrient vectors linking Southwest Atlantic marine ecosystems

NASA Astrophysics Data System (ADS)

Arkhipkin, Alexander I.

2013-10-01

Long-term investigations of three abundant nektonic squid species from the Southwest Atlantic, Illex argentinus, Doryteuthis gahi and Onykia ingens, permitted to estimate important population parameters including individual growth rates, duration of ontogenetic phases and mortalities. Using production model, the productivity of squid populations at different phases of their life cycle was assessed and the amount of biomass they convey between marine ecosystems as a result of their ontogenetic migrations was quantified. It was found that squid are major nutrient vectors and play a key role as transient 'biological pumps' linking spatially distinct marine ecosystems. I. argentinus has the largest impact in all three ecosystems it encounters due to its high abundance and productivity. The variable nature of squid populations increases the vulnerability of these biological conveyers to overfishing and environmental change. Failure of these critical biological pathways may induce irreversible long-term consequences for biodiversity, resource abundance and spatial availability in the world ocean.

Net uptake of atmospheric CO2 by coastal submerged aquatic vegetation

PubMed Central

Tokoro, Tatsuki; Hosokawa, Shinya; Miyoshi, Eiichi; Tada, Kazufumi; Watanabe, Kenta; Montani, Shigeru; Kayanne, Hajime; Kuwae, Tomohiro

2014-01-01

‘Blue Carbon’, which is carbon captured by marine living organisms, has recently been highlighted as a new option for climate change mitigation initiatives. In particular, coastal ecosystems have been recognized as significant carbon stocks because of their high burial rates and long-term sequestration of carbon. However, the direct contribution of Blue Carbon to the uptake of atmospheric CO2 through air-sea gas exchange remains unclear. We performed in situ measurements of carbon flows, including air-sea CO2 fluxes, dissolved inorganic carbon changes, net ecosystem production, and carbon burial rates in the boreal (Furen), temperate (Kurihama), and subtropical (Fukido) seagrass meadows of Japan from 2010 to 2013. In particular, the air-sea CO2 flux was measured using three methods: the bulk formula method, the floating chamber method, and the eddy covariance method. Our empirical results show that submerged autotrophic vegetation in shallow coastal waters can be functionally a sink for atmospheric CO2. This finding is contrary to the conventional perception that most near-shore ecosystems are sources of atmospheric CO2. The key factor determining whether or not coastal ecosystems directly decrease the concentration of atmospheric CO2 may be net ecosystem production. This study thus identifies a new ecosystem function of coastal vegetated systems; they are direct sinks of atmospheric CO2. PMID:24623530

Enabling the Integrated Assessment of Large Marine Ecosystems: Informatics to the Forefront of Science-Based Decision Support

NASA Astrophysics Data System (ADS)

Di Stefano, M.; Fox, P. A.; Beaulieu, S. E.; Maffei, A. R.; West, P.; Hare, J. A.

2012-12-01

Integrated assessments of large marine ecosystems require the understanding of interactions between environmental, ecological, and socio-economic factors that affect production and utilization of marine natural resources. Assessing the functioning of complex coupled natural-human systems calls for collaboration between natural and social scientists across disciplinary and national boundaries. We are developing a platform to implement and sustain informatics solutions for these applications, providing interoperability among very diverse and heterogeneous data and information sources, as well as multi-disciplinary organizations and people. We have partnered with NOAA NMFS scientists to facilitate the deployment of an integrated ecosystem approach to management in the Northeast U.S. (NES) and California Current Large Marine Ecosystems (LMEs). Our platform will facilitate the collaboration and knowledge sharing among NMFS natural and social scientists, promoting community participation in integrating data, models, and knowledge. Here, we present collaborative software tools developed to aid the production of the Ecosystem Status Report (ESR) for the NES LME. The ESR addresses the D-P-S portion of the DPSIR (Driver-Pressure-State-Impact-Response) management framework: reporting data, indicators, and information products for climate drivers, physical and human (fisheries) pressures, and ecosystem state (primary and secondary production and higher trophic levels). We are developing our tools in open-source software, with the main tool based on a web application capable of providing the ability to work on multiple data types from a variety of sources, providing an effective way to share the source code used to generate data products and associated metadata as well as track workflow provenance to allow in the reproducibility of a data product. Our platform retrieves data, conducts standard analyses, reports data quality and other standardized metadata, provides iterative and interactive visualization, and enables the download of data plotted in the ESR. Data, indicators, and information products include time series, geographic maps, and uni-variate and multi-variate analyses. Also central to the success of this initiative is the commitment to accommodate and train scientists of multiple disciplines who will learn to interact effectively with this new integrated and interoperable ecosystem assessment capability. Traceability, repeatability, explanation, verification, and validation of data, indicators, and information products are important for cross-disciplinary understanding and sharing with managers, policymakers, and the public. We are also developing an ontology to support the implementation of the DPSIR framework. These new capabilities will serve as the essential foundation for the formal synthesis and quantitative analysis of information on relevant natural and socio-economic factors in relation to specified ecosystem management goals which can be applied in other LMEs.

The Western South Atlantic Ocean in a High-CO2 World: Current Measurement Capabilities and Perspectives.

PubMed

Kerr, Rodrigo; da Cunha, Letícia C; Kikuchi, Ruy K P; Horta, Paulo A; Ito, Rosane G; Müller, Marius N; Orselli, Iole B M; Lencina-Avila, Jannine M; de Orte, Manoela R; Sordo, Laura; Pinheiro, Bárbara R; Bonou, Frédéric K; Schubert, Nadine; Bergstrom, Ellie; Copertino, Margareth S

2016-03-01

An international multi-disciplinary group of 24 researchers met to discuss ocean acidification (OA) during the Brazilian OA Network/Surface Ocean-Lower Atmosphere Study (BrOA/SOLAS) Workshop. Fifteen members of the BrOA Network (www.broa.furg.br) authored this review. The group concluded that identifying and evaluating the regional effects of OA is impossible without understanding the natural variability of seawater carbonate systems in marine ecosystems through a series of long-term observations. Here, we show that the western South Atlantic Ocean (WSAO) lacks appropriate observations for determining regional OA effects, including the effects of OA on key sensitive Brazilian ecosystems in this area. The impacts of OA likely affect marine life in coastal and oceanic ecosystems, with further social and economic consequences for Brazil and neighboring countries. Thus, we present (i) the diversity of coastal and open ocean ecosystems in the WSAO and emphasize their roles in the marine carbon cycle and biodiversity and their vulnerabilities to OA effects; (ii) ongoing observational, experimental, and modeling efforts that investigate OA in the WSAO; and (iii) highlights of the knowledge gaps, infrastructure deficiencies, and OA-related issues in the WSAO. Finally, this review outlines long-term actions that should be taken to manage marine ecosystems in this vast and unexplored ocean region.

The developing framework of marine ecotoxicology: Pollutants as a variable in marine ecosystems?

USGS Publications Warehouse

Luoma, Samuel N.

1996-01-01

Marine ecosystems include a subset in which at least some interrelated geochemical, biochemical, physiological, population and community characteristics are changed by pollutants. Moderate contamination is relatively widespread in coastal and estuarine ecosystems, so the subset of ecosystems with at least some processes affected could be relatively large. Pollutant influences have changed and will probably continue to change on time scales of decades. Biological exposures and dose in such ecosystems are species-specific and determined by how the species is exposed to different environmental media and the geochemistry of individual pollutants within those media. Bioaccumulation models offer significant promise for interpreting such exposures. Biological responses to pollutants need to be more directly linked to exposure and dose. At the level of the individual this might be improved by better understanding relationships between tissue concentrations of pollutants and responses to pollutants. Multi-discipline field and laboratory studies combined with advanced understanding of some basic processes have reduced the ambiguities in interpreting a few physiological/organismic responses to pollutants in nature. Recognition of pollutant-induced patterns in population responses could lead to similar advances. A rational framework for ecotoxicology is developing, but its further advance is dependent upon better integration of ecotoxicology with basic marine ecology and biology.

Enhanced biodiversity beyond marine reserve boundaries: the cup spillith over.

PubMed

Russ, Garry R; Alcala, Angel C

2011-01-01

Overfishing can have detrimental effects on marine biodiversity and the structure of marine ecosystems. No-take marine reserves (NTMRs) are much advocated as a means of protecting biodiversity and ecosystem structure from overharvest. In contrast to terrestrial protected areas, NTMRs are not only expected to conserve or recover biodiversity and ecosystems within their boundaries, but also to enhance biodiversity beyond their boundaries by exporting species richness and more complex biological communities. Here we show that species richness of large predatory reef fish increased fourfold and 11-fold inside two Philippine no-take marine reserves over 14 and 25 years, respectively. Outside one reserve (Apo) the species richness also increased. This increase beyond the Apo reserve boundary was 78% higher closer to the boundary (200-250 m) than farther from it (250-500 m). The increase in richness beyond the boundary could not be explained by improvements over time in habitat or prey availability. Furthermore, community composition of predatory fish outside but close to (200-250 m) the Apo reserve became very similar to that inside the reserve over time, almost converging with it in multivariate space after 26 years of reserve protection. This is consistent with the suggestion that, as community composition inside Apo reserve increased in complexity, this complexity spilled over the boundary into nearby fished areas. Clearly, the spillover of species richness and community complexity is a direct consequence of the spillover of abundance of multiple species. However, this spillover of species richness and community complexity demonstrates an important benefit of biodiversity and ecosystem export from reserves, and it provides hope that reserves can help to reverse the decline of marine ecosystems and biodiversity.

Towards end-to-end models for investigating the effects of climate and fishing in marine ecosystems

NASA Astrophysics Data System (ADS)

Travers, M.; Shin, Y.-J.; Jennings, S.; Cury, P.

2007-12-01

End-to-end models that represent ecosystem components from primary producers to top predators, linked through trophic interactions and affected by the abiotic environment, are expected to provide valuable tools for assessing the effects of climate change and fishing on ecosystem dynamics. Here, we review the main process-based approaches used for marine ecosystem modelling, focusing on the extent of the food web modelled, the forcing factors considered, the trophic processes represented, as well as the potential use and further development of the models. We consider models of a subset of the food web, models which represent the first attempts to couple low and high trophic levels, integrated models of the whole ecosystem, and size spectrum models. Comparisons within and among these groups of models highlight the preferential use of functional groups at low trophic levels and species at higher trophic levels and the different ways in which the models account for abiotic processes. The model comparisons also highlight the importance of choosing an appropriate spatial dimension for representing organism dynamics. Many of the reviewed models could be extended by adding components and by ensuring that the full life cycles of species components are represented, but end-to-end models should provide full coverage of ecosystem components, the integration of physical and biological processes at different scales and two-way interactions between ecosystem components. We suggest that this is best achieved by coupling models, but there are very few existing cases where the coupling supports true two-way interaction. The advantages of coupling models are that the extent of discretization and representation can be targeted to the part of the food web being considered, making their development time- and cost-effective. Processes such as predation can be coupled to allow the propagation of forcing factors effects up and down the food web. However, there needs to be a stronger focus on enabling two-way interaction, carefully selecting the key functional groups and species, reconciling different time and space scales and the methods of converting between energy, nutrients and mass.

Seabirds as indicators of marine ecosystems: Introduction: A modern role for seabirds as indicators

USGS Publications Warehouse

Piatt, John F.; Sydeman, William J.; Wiese, Francis

2007-01-01

A key requirement for implementing ecosystem-based management is to obtain timely information on significant fluctuations in the ecosystem (Botsford et al. 1997). However, obtaining all necessary information about physical and biological changes at appropriate temporal and spatial scales is a daunting task. Intuitively, one might assume that physical data are more important for the interpretation of ecosystem changes than biological data, but analyses of time series data suggest otherwise: physical data are more erratic and often confusing over the short term compared to biological data, which tend to fluctuate less on annual time scales (Hare & Mantua 2000). Even so, biological time-series may also be confusing when coexisting marine species respond differently to ecosystem variability. For example, while warming temperatures in the Gulf of Alaska following the 1976 to 1977 regime shift favored an increase in gadoids and flatfish, a variety of forage fish and pandalid shrimp species virtually disappeared (Anderson & Piatt 1999). Zooplankton communities in the Gulf of Alaska also demonstrated similar patterns of response (Francis et al. 1998). At the basin scale, favorable conditions for salmon in Alaska following the regime shift were matched inversely by poor conditions in the California Current (Francis et al. 1998). In marine birds, subtropical species increased, while subarctic ones decreased during a warming phase in the southern California Bight. Clearly, no single index can tell the whole story accurately. Multi-species, multi-region, and multi-trophic level approaches are needed to quantify fluctuations in marine ecosystem processes and in the distribution and abundance of its inhabitants, to determine critical parameter thresholds and to use this information in management and marine conservation.

Effects of near-future ocean acidification, fishing, and marine protection on a temperate coastal ecosystem.

PubMed

Cornwall, Christopher E; Eddy, Tyler D

2015-02-01

Understanding ecosystem responses to global and local anthropogenic impacts is paramount to predicting future ecosystem states. We used an ecosystem modeling approach to investigate the independent and cumulative effects of fishing, marine protection, and ocean acidification on a coastal ecosystem. To quantify the effects of ocean acidification at the ecosystem level, we used information from the peer-reviewed literature on the effects of ocean acidification. Using an Ecopath with Ecosim ecosystem model for the Wellington south coast, including the Taputeranga Marine Reserve (MR), New Zealand, we predicted ecosystem responses under 4 scenarios: ocean acidification + fishing; ocean acidification + MR (no fishing); no ocean acidification + fishing; no ocean acidification + MR for the year 2050. Fishing had a larger effect on trophic group biomasses and trophic structure than ocean acidification, whereas the effects of ocean acidification were only large in the absence of fishing. Mortality by fishing had large, negative effects on trophic group biomasses. These effects were similar regardless of the presence of ocean acidification. Ocean acidification was predicted to indirectly benefit certain species in the MR scenario. This was because lobster (Jasus edwardsii) only recovered to 58% of the MR biomass in the ocean acidification + MR scenario, a situation that benefited the trophic groups lobsters prey on. Most trophic groups responded antagonistically to the interactive effects of ocean acidification and marine protection (46%; reduced response); however, many groups responded synergistically (33%; amplified response). Conservation and fisheries management strategies need to account for the reduced recovery potential of some exploited species under ocean acidification, nonadditive interactions of multiple factors, and indirect responses of species to ocean acidification caused by declines in calcareous predators. © 2014 Society for Conservation Biology.

Linking ecosystems, food webs, and fish production: subsidies in salmonid watersheds

USGS Publications Warehouse

Wipfli, Mark S.; Baxter, Colden V.

2010-01-01

Physical characteristics of riverine habitats, such as large wood abundance, pool geometry and abundance, riparian vegetation cover, and surface flow conditions, have traditionally been thought to constrain fish production in these ecosystems. Conversely, the role of food resources (quantity and quality) in controlling fish production has received far less attention and consideration, though they can also be key productivity drivers. Traditional freshwater food web illustrations have typically conveyed the notion that most fish food is produced within the local aquatic habitat itself, but the concepts and model we synthesize in this article show that most fish food comes from external or very distant sources—including subsidies from marine systems borne from adult returns of anadromous fishes, from fishless headwater tributaries that transport prey to downstream fish, and from adjacent streamside vegetation and associated habitats. The model we propose further illustrates how key trophic pathways and food sources vary through time and space throughout watersheds. Insights into how food supplies affect fishes can help guide how we view riverine ecosystems, their structure and function, their interactions with marine and terrestrial systems, and how we manage natural resources, including fish, riparian habitats, and forests.

Characterizing local biological hotspots in the Gulf of Maine using remote sensing data

NASA Astrophysics Data System (ADS)

Ribera, Marta M.

Researchers increasingly advocate the use of ecosystem-based management (EBM) for managing complex marine ecosystems. This approach requires managers to focus on processes and cross-scale interactions, rather than individual components. However, they often lack appropriate tools and data sources to pursue this change in management approach. One method that has been proposed to understand the ecological complexity inherent in marine ecosystems is the study of biological hotspots. Biological hotspots are locations where organisms from different trophic levels aggregate to feed on abundant supplies, and they are considered a first step toward understanding the processes driving spatial and temporal heterogeneity in marine systems. Biological hotspots are supported by phytoplankton aggregations, which are characterized by high spatial and temporal variability. As a result, methods developed to locate biological hotspots in relatively stable terrestrial systems are not well suited for more dynamic marine ecosystems. The main objective of this thesis is thus to identify and characterize local-scale biological hotspots in the western side of the Gulf of Maine. The first chapter describes a new methodological framework with the steps needed to locate these types of hotspots in marine ecosystems using remote sensing datasets. Then, in the second chapter these hotspots are characterized using a novel metric that uses time series information and spatial statistics to account for both the temporal variability and spatial structure of these marine aggregations. This metric redefines biological hotspots as areas with a high probability of exhibiting positive anomalies of productivity compared to the expected regional seasonal pattern. Finally, the third chapter compares the resulting biological hotspots to fishery-dependent abundance indices of surface and benthic predators to determine the effect of the location and magnitude of phytoplankton aggregations on the rest of the ecosystem. Analyses indicate that the spatial scale and magnitude of biological hotspots in the Gulf of Maine depend on the location and time of the year. Results also show that these hotspots change over time in response to both short-term oceanographic processes and long-term climatic cycles. Finally, the new metric presented here facilitates the spatial comparison between different trophic levels, thus allowing interdisciplinary ecosystem-wide studies.

Marine Mammals and Climate Change in the Pacific Arctic: Impacts & Resilience

NASA Astrophysics Data System (ADS)

Moore, S. E.

2014-12-01

Extreme reductions in Arctic sea ice extent and thickness have become a hallmark of climate change, but impacts to the marine ecosystem are poorly understood. As top predators, marine mammals must adapt to biological responses to physical forcing and thereby become sentinels to ecosystem variability and reorganization. Recent sea ice retreats have influenced the ecology of marine mammals in the Pacific Arctic sector. Walruses now often haul out by the thousands along the NW Alaska coast in late summer, and reports of harbor porpoise, humpback, fin and minke whales in the Chukchi Sea demonstrate that these temperate species routinely occur there. In 2010, satellite tagged bowhead whales from Atlantic and Pacific populations met in the Northwest Passage, an overlap thought precluded by sea ice since the Holocene. To forage effectively, baleen whales must target dense patches of zooplankton and small fishes. In the Pacific Arctic, bowhead and gray whales appear to be responding to enhanced prey availability delivered both by new production and advection pathways. Two programs, the Distributed Biological Observatory (DBO) and the Synthesis of Arctic Research (SOAR), include tracking of marine mammal and prey species' responses to ecosystem shifts associated with sea ice loss. Both programs provide an integrated-ecosystem baseline in support of the development of a web-based Marine Mammal Health Map, envisioned as a component of the U.S. Integrated Ocean Observing System (IOOS). An overarching goal is to identify ecological patterns for marine mammals in the 'new' Arctic, as a foundation for integrative research, local response and adaptive management.

Using ecosystem indicators to track effects of recent warm conditions in Alaska's Large Marine Ecosystems

NASA Astrophysics Data System (ADS)

Zador, S.; Ormseth, O.; Renner, H.

2016-02-01

A comprehensive suite of ecosystem indicators, defined simply here as time-series of data that measure some component of an ecosystem, can provide a holistic and long-term view of ecosystem status and response to change. In Alaska, marine ecosystem indicators are tracked in the Gulf of Alaska, Aleutian Islands and eastern Bering Sea to inform annual ecosystem assessments for managers and scientists, and in particular, to inform ecosystem-based fisheries management. We will present the most recent indicator-based assessments of these three large marine ecosystems (LMEs) that integrate data from climate and oceanographic indicators through lower and upper-trophic biological indicators and highlight regional and species-specific apparent responses to the recent warm anomalies in the North Pacific. We will use comparisons among the three LMEs to illustrate how the effects of the anomalies may propagate through ecosystems and food webs. In general, we expect to see more changes in indicators' status that may be attributed to the Warm Blob in the Gulf of Alaska relative to the other LMEs, as a result of the proximity of the Gulf of Alaska to the areas where the temperature anomalies originated. In the eastern Bering Sea, which is separated from the North Pacific by the Aleutian Island chain, we expect to see more modulated responses. We will discuss the types of biological indicators that are expected to show direct responses to temperatures, such as changes in species distribution, compared to those that may show lagged effects.

Immediate ecotoxicological effects of short-lived oil spills on marine biota

PubMed Central

Brussaard, Corina P. D.; Peperzak, Louis; Beggah, Siham; Wick, Lukas Y.; Wuerz, Birgit; Weber, Jan; Samuel Arey, J.; van der Burg, Bart; Jonas, Arjen; Huisman, Johannes; van der Meer, Jan Roelof

2016-01-01

Marine environments are frequently exposed to oil spills as a result of transportation, oil drilling or fuel usage. Whereas large oil spills and their effects have been widely documented, more common and recurrent small spills typically escape attention. To fill this important gap in the assessment of oil-spill effects, we performed two independent supervised full sea releases of 5 m3 of crude oil, complemented by on-board mesocosm studies and sampling of accidentally encountered slicks. Using rapid on-board biological assays, we detect high bioavailability and toxicity of dissolved and dispersed oil within 24 h after the spills, occurring fairly deep (8 m) below the slicks. Selective decline of marine plankton is observed, equally relevant for early stages of larger spills. Our results demonstrate that, contrary to common thinking, even small spills have immediate adverse biological effects and their recurrent nature is likely to affect marine ecosystem functioning. PMID:27041738

Immediate ecotoxicological effects of short-lived oil spills on marine biota.

PubMed

Brussaard, Corina P D; Peperzak, Louis; Beggah, Siham; Wick, Lukas Y; Wuerz, Birgit; Weber, Jan; Samuel Arey, J; van der Burg, Bart; Jonas, Arjen; Huisman, Johannes; van der Meer, Jan Roelof

2016-04-04

Marine environments are frequently exposed to oil spills as a result of transportation, oil drilling or fuel usage. Whereas large oil spills and their effects have been widely documented, more common and recurrent small spills typically escape attention. To fill this important gap in the assessment of oil-spill effects, we performed two independent supervised full sea releases of 5 m(3) of crude oil, complemented by on-board mesocosm studies and sampling of accidentally encountered slicks. Using rapid on-board biological assays, we detect high bioavailability and toxicity of dissolved and dispersed oil within 24 h after the spills, occurring fairly deep (8 m) below the slicks. Selective decline of marine plankton is observed, equally relevant for early stages of larger spills. Our results demonstrate that, contrary to common thinking, even small spills have immediate adverse biological effects and their recurrent nature is likely to affect marine ecosystem functioning.

Assessing the trophic position and ecological role of squids in marine ecosystems by means of food-web models

NASA Astrophysics Data System (ADS)

Coll, Marta; Navarro, Joan; Olson, Robert J.; Christensen, Villy

2013-10-01

We synthesized available information from ecological models at local and regional scales to obtain a global picture of the trophic position and ecological role of squids in marine ecosystems. First, static food-web models were used to analyze basic ecological parameters and indicators of squids: biomass, production, consumption, trophic level, omnivory index, predation mortality diet, and the ecological role. In addition, we developed various dynamic temporal simulations using two food-web models that included squids in their parameterization, and we investigated potential impacts of fishing pressure and environmental conditions for squid populations and, consequently, for marine food webs. Our results showed that squids occupy a large range of trophic levels in marine food webs and show a large trophic width, reflecting the versatility in their feeding behaviors and dietary habits. Models illustrated that squids are abundant organisms in marine ecosystems, and have high growth and consumption rates, but these parameters are highly variable because squids are adapted to a large variety of environmental conditions. Results also show that squids can have a large trophic impact on other elements of the food web, and top-down control from squids to their prey can be high. In addition, some squid species are important prey of apical predators and may be keystone species in marine food webs. In fact, we found strong interrelationships between neritic squids and the populations of their prey and predators in coastal and shelf areas, while the role of squids in open ocean and upwelling ecosystems appeared more constrained to a bottom-up impact on their predators. Therefore, large removals of squids will likely have large-scale effects on marine ecosystems. In addition, simulations confirm that squids are able to benefit from a general increase in fishing pressure, mainly due to predation release, and quickly respond to changes triggered by the environment. Squids may thus be very sensitive to the effects of fishing and climate change.

Modeling Complex Marine Ecosystems: An Investigation of Two Teaching Approaches with Fifth Graders

ERIC Educational Resources Information Center

Papaevripidou, M.; Constantinou, C. P.; Zacharia, Z. C.

2007-01-01

This study investigated acquisition and transfer of the modeling ability of fifth graders in various domains. Teaching interventions concentrated on the topic of marine ecosystems either through a modeling-based approach or a worksheet-based approach. A quasi-experimental (pre-post comparison study) design was used. The control group (n = 17)…

Phytoplankton Biomass Distribution and Identification of Productive Habitats Within the Galapagos Marine Reserve by MODIS, a Surface Acquisition System, and In-Situ Measurements

EPA Science Inventory

The Galapagos Marine Reserve (GMR) is one of the most diverse ecosystems in the world. Phytoplankton are the base of the ecosystem food chain for many higher trophic organisms, so identifying phytoplankton biomass distribution is the first step in understanding the dynamic envir...

Using Large Marine Ecosystems and Cultural Responsiveness as the Context for Professional Development of Teachers and Scientists in Ocean Sciences

ERIC Educational Resources Information Center

Sigman, Marilyn; Dublin, Robin; Anderson, Andrea; Deans, Nora; Warburton, Janet; Matsumoto, George I.; Dugan, Darcy; Harcharek, Jana

2014-01-01

During 2010-2012, three professional development workshops brought together K-12 educators and scientists conducting research in the geographic and ecological context of Alaska's three large marine ecosystems (Bering Sea/Aleutians, Gulf of Alaska, and Arctic Ocean). Educators successfully applied new scientific knowledge gained from their…

A Dynamic Energy Budget (DEB) model to describe Laternula elliptica (King, 1832) seasonal feeding and metabolism

PubMed Central

Ahn, In-Young; Guillaumot, Charlène; Danis, Bruno

2017-01-01

Antarctic marine organisms are adapted to an extreme environment, characterized by a very low but stable temperature and a strong seasonality in food availability arousing from variations in day length. Ocean organisms are particularly vulnerable to global climate change with some regions being impacted by temperature increase and changes in primary production. Climate change also affects the biotic components of marine ecosystems and has an impact on the distribution and seasonal physiology of Antarctic marine organisms. Knowledge on the impact of climate change in key species is highly important because their performance affects ecosystem functioning. To predict the effects of climate change on marine ecosystems, a holistic understanding of the life history and physiology of Antarctic key species is urgently needed. DEB (Dynamic Energy Budget) theory captures the metabolic processes of an organism through its entire life cycle as a function of temperature and food availability. The DEB model is a tool that can be used to model lifetime feeding, growth, reproduction, and their responses to changes in biotic and abiotic conditions. In this study, we estimate the DEB model parameters for the bivalve Laternula elliptica using literature-extracted and field data. The DEB model we present here aims at better understanding the biology of L. elliptica and its levels of adaptation to its habitat with a special focus on food seasonality. The model parameters describe a metabolism specifically adapted to low temperatures, with a low maintenance cost and a high capacity to uptake and mobilise energy, providing this organism with a level of energetic performance matching that of related species from temperate regions. It was also found that L. elliptica has a large energy reserve that allows enduring long periods of starvation. Additionally, we applied DEB parameters to time-series data on biological traits (organism condition, gonad growth) to describe the effect of a varying environment in food and temperature on the organism condition and energy use. The DEB model developed here for L. elliptica allowed us to improve benchmark knowledge on the ecophysiology of this key species, providing new insights in the role of food availability and temperature on its life cycle and reproduction strategy. PMID:28850607

A Dynamic Energy Budget (DEB) model to describe Laternula elliptica (King, 1832) seasonal feeding and metabolism.

PubMed

Agüera, Antonio; Ahn, In-Young; Guillaumot, Charlène; Danis, Bruno

2017-01-01

Antarctic marine organisms are adapted to an extreme environment, characterized by a very low but stable temperature and a strong seasonality in food availability arousing from variations in day length. Ocean organisms are particularly vulnerable to global climate change with some regions being impacted by temperature increase and changes in primary production. Climate change also affects the biotic components of marine ecosystems and has an impact on the distribution and seasonal physiology of Antarctic marine organisms. Knowledge on the impact of climate change in key species is highly important because their performance affects ecosystem functioning. To predict the effects of climate change on marine ecosystems, a holistic understanding of the life history and physiology of Antarctic key species is urgently needed. DEB (Dynamic Energy Budget) theory captures the metabolic processes of an organism through its entire life cycle as a function of temperature and food availability. The DEB model is a tool that can be used to model lifetime feeding, growth, reproduction, and their responses to changes in biotic and abiotic conditions. In this study, we estimate the DEB model parameters for the bivalve Laternula elliptica using literature-extracted and field data. The DEB model we present here aims at better understanding the biology of L. elliptica and its levels of adaptation to its habitat with a special focus on food seasonality. The model parameters describe a metabolism specifically adapted to low temperatures, with a low maintenance cost and a high capacity to uptake and mobilise energy, providing this organism with a level of energetic performance matching that of related species from temperate regions. It was also found that L. elliptica has a large energy reserve that allows enduring long periods of starvation. Additionally, we applied DEB parameters to time-series data on biological traits (organism condition, gonad growth) to describe the effect of a varying environment in food and temperature on the organism condition and energy use. The DEB model developed here for L. elliptica allowed us to improve benchmark knowledge on the ecophysiology of this key species, providing new insights in the role of food availability and temperature on its life cycle and reproduction strategy.

Shrinking of fishes exacerbates impacts of global ocean changes on marine ecosystems

NASA Astrophysics Data System (ADS)

Cheung, William W. L.; Sarmiento, Jorge L.; Dunne, John; Frölicher, Thomas L.; Lam, Vicky W. Y.; Deng Palomares, M. L.; Watson, Reg; Pauly, Daniel

2013-03-01

Changes in temperature, oxygen content and other ocean biogeochemical properties directly affect the ecophysiology of marine water-breathing organisms. Previous studies suggest that the most prominent biological responses are changes in distribution, phenology and productivity. Both theory and empirical observations also support the hypothesis that warming and reduced oxygen will reduce body size of marine fishes. However, the extent to which such changes would exacerbate the impacts of climate and ocean changes on global marine ecosystems remains unexplored. Here, we employ a model to examine the integrated biological responses of over 600 species of marine fishes due to changes in distribution, abundance and body size. The model has an explicit representation of ecophysiology, dispersal, distribution, and population dynamics. We show that assemblage-averaged maximum body weight is expected to shrink by 14-24% globally from 2000 to 2050 under a high-emission scenario. About half of this shrinkage is due to change in distribution and abundance, the remainder to changes in physiology. The tropical and intermediate latitudinal areas will be heavily impacted, with an average reduction of more than 20%. Our results provide a new dimension to understanding the integrated impacts of climate change on marine ecosystems.

Composition and predicted functional ecology of mussel-associated bacteria in Indonesian marine lakes.

PubMed

Cleary, Daniel F R; Becking, Leontine E; Polónia, Ana R M; Freitas, Rossana M; Gomes, Newton C M

2015-03-01

In the present study, we sampled bacterial communities associated with mussels inhabiting two distinct coastal marine ecosystems in Kalimantan, Indonesia, namely, marine lakes and coastal mangroves. We used 16S rRNA gene pyrosequencing and predicted metagenomic analysis to compare microbial composition and function. Marine lakes are small landlocked bodies of seawater isolated to varying degrees from the open sea environment. They contain numerous endemic taxa and represent natural laboratories of speciation. Our primary goals were to (1) use BLAST search to identify closely related organisms to dominant bacterial OTUs in our mussel dataset and (2) to compare bacterial communities and enrichment in the predicted bacterial metagenome among lakes. Our sequencing effort yielded 3553 OTUs belonging to 44 phyla, 99 classes and 121 orders. Mussels in the largest marine lake (Kakaban) and the coastal mangrove habitat were dominated by bacteria belonging to the phylum Proteobacteria whereas smaller lakes, located on the island of Maratua, were dominated by bacteria belonging to the phyla Firmicutes and Tenericutes. The single most abundant OTU overall was assigned to the genus Mycoplasma. There were several significant differences among locations with respect to metabolic pathways. These included enrichment of xenobiotic biodegradation pathways in the largest marine lake and coastal mangrove. These locations were also the most enriched with respect to nitrogen metabolism. The presence of genes related to isoquinoline alkaloids, polyketides, hydrolases, mono and dioxygenases in the predicted analysis of functional pathways is an indication that the bacterial communities of Brachidontes mussels may be potentially important sources of new marine medicines and enzymes of industrial interest. Future work should focus on measuring how mussel microbial communities influence nutrient dynamics within the marine lake environment and isolating microbes with potential biotechnological applications.

Ecosystem Model Skill Assessment. Yes We Can!

PubMed Central

Olsen, Erik; Fay, Gavin; Gaichas, Sarah; Gamble, Robert; Lucey, Sean; Link, Jason S.

2016-01-01

Need to Assess the Skill of Ecosystem Models Accelerated changes to global ecosystems call for holistic and integrated analyses of past, present and future states under various pressures to adequately understand current and projected future system states. Ecosystem models can inform management of human activities in a complex and changing environment, but are these models reliable? Ensuring that models are reliable for addressing management questions requires evaluating their skill in representing real-world processes and dynamics. Skill has been evaluated for just a limited set of some biophysical models. A range of skill assessment methods have been reviewed but skill assessment of full marine ecosystem models has not yet been attempted. Northeast US Atlantis Marine Ecosystem Model We assessed the skill of the Northeast U.S. (NEUS) Atlantis marine ecosystem model by comparing 10-year model forecasts with observed data. Model forecast performance was compared to that obtained from a 40-year hindcast. Multiple metrics (average absolute error, root mean squared error, modeling efficiency, and Spearman rank correlation), and a suite of time-series (species biomass, fisheries landings, and ecosystem indicators) were used to adequately measure model skill. Overall, the NEUS model performed above average and thus better than expected for the key species that had been the focus of the model tuning. Model forecast skill was comparable to the hindcast skill, showing that model performance does not degenerate in a 10-year forecast mode, an important characteristic for an end-to-end ecosystem model to be useful for strategic management purposes. Skill Assessment Is Both Possible and Advisable We identify best-practice approaches for end-to-end ecosystem model skill assessment that would improve both operational use of other ecosystem models and future model development. We show that it is possible to not only assess the skill of a complicated marine ecosystem model, but that it is necessary do so to instill confidence in model results and encourage their use for strategic management. Our methods are applicable to any type of predictive model, and should be considered for use in fields outside ecology (e.g. economics, climate change, and risk assessment). PMID:26731540

Recommendations for developing and applying genetic tools to assess and manage biological invasions in marine ecosystems

PubMed Central

Darling, John A.; Galil, Bella S.; Carvalho, Gary R.; Rius, Marc; Viard, Frédérique; Piraino, Stefano

2018-01-01

The European Union’s Marine Strategy Framework Directive (MSFD) aims to adopt integrated ecosystem management approaches to achieve or maintain “Good Environmental Status” for marine waters, habitats and resources, including mitigation of the negative effects of non-indigenous species (NIS). The Directive further seeks to promote broadly standardized monitoring efforts and assessment of temporal trends in marine ecosystem condition, incorporating metrics describing the distribution and impacts of NIS. Accomplishing these goals will require application of advanced tools for NIS surveillance and risk assessment, particularly given known challenges associated with surveying and monitoring with traditional methods. In the past decade, a host of methods based on nucleic acids (DNA and RNA) analysis have been developed or advanced that promise to dramatically enhance capacity in assessing and managing NIS. However, ensuring that these rapidly evolving approaches remain accessible and responsive to the needs of resource managers remains a challenge. This paper provides recommendations for future development of these genetic tools for assessment and management of NIS in marine systems, within the context of the explicit requirements of the MSFD. Issues considered include technological innovation, methodological standardization, data sharing and collaboration, and the critical importance of shared foundational resources, particularly integrated taxonomic expertise. Though the recommendations offered here are not exhaustive, they provide a basis for future intentional (and international) collaborative development of a genetic toolkit for NIS research, capable of fulfilling the immediate and long term goals of marine ecosystem and resource conservation. PMID:29681680

78 FR 66683 - Fisheries in the Western Pacific; Special Coral Reef Ecosystem Fishing Permit

Federal Register 2010, 2011, 2012, 2013, 2014

2013-11-06

... the Western Pacific; Special Coral Reef Ecosystem Fishing Permit AGENCY: National Marine Fisheries... special coral reef ecosystem fishing permit. SUMMARY: NMFS issued a Special Coral Reef Ecosystem Fishing Permit that authorizes Kampachi Farms, LLC, to culture and harvest a coral reef ecosystem management unit...

Overfishing reduces resilience of kelp beds to climate-driven catastrophic phase shift.

PubMed

Ling, S D; Johnson, C R; Frusher, S D; Ridgway, K R

2009-12-29

A key consideration in assessing impacts of climate change is the possibility of synergistic effects with other human-induced stressors. In the ocean realm, climate change and overfishing pose two of the greatest challenges to the structure and functioning of marine ecosystems. In eastern Tasmania, temperate coastal waters are warming at approximately four times the global ocean warming average, representing the fastest rate of warming in the Southern Hemisphere. This has driven range extension of the ecologically important long-spined sea urchin (Centrostephanus rodgersii), which has now commenced catastrophic overgrazing of productive Tasmanian kelp beds leading to loss of biodiversity and important rocky reef ecosystem services. Coincident with the overgrazing is heavy fishing of reef-based predators including the spiny lobster Jasus edwardsii. By conducting experiments inside and outside Marine Protected Areas we show that fishing, by removing large predatory lobsters, has reduced the resilience of kelp beds against the climate-driven threat of the sea urchin and thus increased risk of catastrophic shift to widespread sea urchin barrens. This shows that interactions between multiple human-induced stressors can exacerbate nonlinear responses of ecosystems to climate change and limit the adaptive capacity of these systems. Management actions focused on reducing the risk of catastrophic phase shift in ecosystems are particularly urgent in the face of ongoing warming and unprecedented levels of predator removal from the world's oceans.

Overfishing reduces resilience of kelp beds to climate-driven catastrophic phase shift

PubMed Central

Ling, S. D.; Johnson, C. R.; Frusher, S. D.; Ridgway, K. R.

2009-01-01

A key consideration in assessing impacts of climate change is the possibility of synergistic effects with other human-induced stressors. In the ocean realm, climate change and overfishing pose two of the greatest challenges to the structure and functioning of marine ecosystems. In eastern Tasmania, temperate coastal waters are warming at approximately four times the global ocean warming average, representing the fastest rate of warming in the Southern Hemisphere. This has driven range extension of the ecologically important long-spined sea urchin (Centrostephanus rodgersii), which has now commenced catastrophic overgrazing of productive Tasmanian kelp beds leading to loss of biodiversity and important rocky reef ecosystem services. Coincident with the overgrazing is heavy fishing of reef-based predators including the spiny lobster Jasus edwardsii. By conducting experiments inside and outside Marine Protected Areas we show that fishing, by removing large predatory lobsters, has reduced the resilience of kelp beds against the climate-driven threat of the sea urchin and thus increased risk of catastrophic shift to widespread sea urchin barrens. This shows that interactions between multiple human-induced stressors can exacerbate nonlinear responses of ecosystems to climate change and limit the adaptive capacity of these systems. Management actions focused on reducing the risk of catastrophic phase shift in ecosystems are particularly urgent in the face of ongoing warming and unprecedented levels of predator removal from the world's oceans. PMID:20018706

Global deglaciation and the re-appearance of microbial matground-dominated ecosystems in the late Paleozoic of Gondwana.

PubMed

Buatois, L A; Netto, R G; Gabriela Mángano, M; Carmona, N B

2013-07-01

The extensive matgrounds in Carboniferous-Permian open-marine deposits of western Argentina constitute an anachronistic facies, because with the onset of penetrative bioturbation during the early Paleozoic microbial mats essentially disappeared from these settings. Abundant microbially induced sedimentary structures in the Argentinean deposits are coincident with the disappearance of trace and body fossils in the succession and with a landward facies shift indicative of transgressive conditions. Deposits of the Late Carboniferous-Early Permian glacial event are well developed in adjacent basins in eastern Argentina, Brazil, South Africa and Antarctica, but do not occur in the western Andean basins of Argentina. However, the deglaciation phase is indirectly recorded in the studied region by a rapid rise in sea level referred to as the Stephanian-Asselian transgression. We suggest that an unusual release of meltwater during the final deglaciation episode of the Gondwana Ice Age may have dramatically freshened peri-Gondwanan seas, impacting negatively on coastal and shallow-marine benthic faunas. Suppression of bioturbation was therefore conducive to a brief re-appearance of matground-dominated ecosystems, reminiscent of those in the precambrian. Bioturbation is essential for ecosystem performance and plays a major role in ocean and sediment geochemistry. Accordingly, the decimation of the mixed layer during deglaciation in the Gondwana basins may have altered ecosystem functioning and geochemical cycling. © 2013 John Wiley & Sons Ltd.

Slowing down of North Pacific climate variability and its implications for abrupt ecosystem change.

PubMed

Boulton, Chris A; Lenton, Timothy M

2015-09-15

Marine ecosystems are sensitive to stochastic environmental variability, with higher-amplitude, lower-frequency--i.e., "redder"--variability posing a greater threat of triggering large ecosystem changes. Here we show that fluctuations in the Pacific Decadal Oscillation (PDO) index have slowed down markedly over the observational record (1900-present), as indicated by a robust increase in autocorrelation. This "reddening" of the spectrum of climate variability is also found in regionally averaged North Pacific sea surface temperatures (SSTs), and can be at least partly explained by observed deepening of the ocean mixed layer. The progressive reddening of North Pacific climate variability has important implications for marine ecosystems. Ecosystem variables that respond linearly to climate forcing will have become prone to much larger variations over the observational record, whereas ecosystem variables that respond nonlinearly to climate forcing will have become prone to more frequent "regime shifts." Thus, slowing down of North Pacific climate variability can help explain the large magnitude and potentially the quick succession of well-known abrupt changes in North Pacific ecosystems in 1977 and 1989. When looking ahead, despite model limitations in simulating mixed layer depth (MLD) in the North Pacific, global warming is robustly expected to decrease MLD. This could potentially reverse the observed trend of slowing down of North Pacific climate variability and its effects on marine ecosystems.

Marine ecosystem resilience during extreme deoxygenation: the Early Jurassic oceanic anoxic event.

PubMed

Caswell, Bryony A; Frid, Christopher L J

2017-01-01

Global warming during the Early Jurassic, and associated widespread ocean deoxygenation, was comparable in scale with the changes projected for the next century. This study quantifies the impact of severe global environmental change on the biological traits of marine communities that define the ecological roles and functions they deliver. We document centennial-millennial variability in the biological trait composition of Early Jurassic (Toarcian) seafloor communities and examine how this changed during the event using biological traits analysis. Environmental changes preceding the global oceanic anoxic event (OAE) produced an ecological shift leading to stressed benthic palaeocommunities with reduced resilience to the subsequent OAE. Changes in traits and ecological succession coincided with major environmental changes; and were of similar nature and magnitude to those in severely deoxygenated benthic communities today despite the very different timescales. Changes in community composition were linked to local redox conditions whereas changes in populations of opportunists were driven by primary productivity. Throughout most of the OAE substitutions by tolerant taxa conserved the trait composition and hence functioning, but periods of severe deoxygenation caused benthic defaunation that would have resulted in functional collapse. Following the OAE recovery was slow probably because the global nature of the event restricted opportunities for recruitment from outside the basin. Our findings suggest that future systems undergoing deoxygenation may initially show functional resilience, but severe global deoxygenation will impact traits and ecosystem functioning and, by limiting the species pool, will slow recovery rates.

Architecture of marine food webs: To be or not be a 'small-world'.

PubMed

Marina, Tomás Ignacio; Saravia, Leonardo A; Cordone, Georgina; Salinas, Vanesa; Doyle, Santiago R; Momo, Fernando R

2018-01-01

The search for general properties in network structure has been a central issue for food web studies in recent years. One such property is the small-world topology that combines a high clustering and a small distance between nodes of the network. This property may increase food web resilience but make them more sensitive to the extinction of connected species. Food web theory has been developed principally from freshwater and terrestrial ecosystems, largely omitting marine habitats. If theory needs to be modified to accommodate observations from marine ecosystems, based on major differences in several topological characteristics is still on debate. Here we investigated if the small-world topology is a common structural pattern in marine food webs. We developed a novel, simple and statistically rigorous method to examine the largest set of complex marine food webs to date. More than half of the analyzed marine networks exhibited a similar or lower characteristic path length than the random expectation, whereas 39% of the webs presented a significantly higher clustering than its random counterpart. Our method proved that 5 out of 28 networks fulfilled both features of the small-world topology: short path length and high clustering. This work represents the first rigorous analysis of the small-world topology and its associated features in high-quality marine networks. We conclude that such topology is a structural pattern that is not maximized in marine food webs; thus it is probably not an effective model to study robustness, stability and feasibility of marine ecosystems.

Does ecosystem variability explain phytoplankton diversity? Solving an ecological puzzle with long-term data sets

NASA Astrophysics Data System (ADS)

Sarker, Subrata; Lemke, Peter; Wiltshire, Karen H.

2018-05-01

Explaining species diversity as a function of ecosystem variability is a long-term discussion in community-ecology research. Here, we aimed to establish a causal relationship between ecosystem variability and phytoplankton diversity in a shallow-sea ecosystem. We used long-term data on biotic and abiotic factors from Helgoland Roads, along with climate data to assess the effect of ecosystem variability on phytoplankton diversity. A point cumulative semi-variogram method was used to estimate the long-term ecosystem variability. A Markov chain model was used to estimate dynamical processes of species i.e. occurrence, absence and outcompete probability. We identified that the 1980s was a period of high ecosystem variability while the last two decades were comparatively less variable. Ecosystem variability was found as an important predictor of phytoplankton diversity at Helgoland Roads. High diversity was related to low ecosystem variability due to non-significant relationship between probability of a species occurrence and absence, significant negative relationship between probability of a species occurrence and probability of a species to be outcompeted by others, and high species occurrence at low ecosystem variability. Using an exceptional marine long-term data set, this study established a causal relationship between ecosystem variability and phytoplankton diversity.

Towards an impact assessment of bauxite red mud waste on the knowledge of the structure and functions of bathyal ecosystems: The example of the Cassidaigne canyon (north-western Mediterranean Sea).

PubMed

Dauvin, Jean-Claude

2010-02-01

Since 1967, the alumina plants in the Marseilles area (Barasse and Gardanne) have been discharging the mineral residue (i.e., red mud) resulting from the alkaline processing of bauxite into the submarine Cassidaigne canyon (north-western Mediterranean Sea) through pipes situated at 320-330 m in depth. The Barasse pipe stopped being used in 1988. From 1987 to 1996, many decrees and regulations were promulgated by the French State to rule the conditions under which the Gardanne alumina refinery was authorized to dispose of the bauxite residue in the sea. The refinery was required: (i) to study the hydrodynamic circulation in the Cassidaigne canyon to evaluate the potential dispersion and transport of fine elements discharged into the water mass and their impact on the pelagic ecosystem; (ii) to survey the marine environment every five years to control the expansion and thickness of the red mud deposit and compare the evolution of the benthic macrofauna at representative sampling sites in the environment affected by the red mud discharge with that of reference sites outside of the red mud plume; (iii) to study the effect of the discharge on fishing activities; and (iv) to investigate the toxicity of the red mud, particularly its persistence, accumulation, interaction and effect on the marine ecosystem, paying special attention to the bio-accumulation of chromium and vanadium. A Scientific Committee was created to insure an independent evaluation of the studies promised by the manufacturer in response to the State's regulations. Since the beginning of the 1960s, data have been accumulating on the structure and long-term functioning of the Cassidaigne bathyal ecosystem. This paper presents the collaborative efforts of the State-Manufacturer-Committee triplet and summarizes the main results obtained during the last period's sea campaigns (1991-2007). This paper also illustrates how national regulations concerning manufacturers, such as Gardanne alumina refinery, have provided new knowledge about the structure and functioning of a bathyal ecosystem in the Cassidaigne canyon in the north-western Mediterranean Sea. Copyright 2009 Elsevier Ltd. All rights reserved.

Dissolved Oxygen Sensor in Animal-Borne Instruments: An Innovation for Monitoring the Health of Oceans and Investigating the Functioning of Marine Ecosystems.

PubMed

Bailleul, Frederic; Vacquie-Garcia, Jade; Guinet, Christophe

2015-01-01

The current decline in dissolved oxygen concentration within the oceans is a sensitive indicator of the effect of climate change on marine environment. However the impact of its declining on marine life and ecosystems' health is still quite unclear because of the difficulty in obtaining in situ data, especially in remote areas, like the Southern Ocean (SO). Southern elephant seals (Mirounga leonina) proved to be a relevant alternative to the traditional oceanographic platforms to measure physical and biogeochemical structure of oceanic regions rarely observed. In this study, we use a new stage of development in biologging technology to draw a picture of dissolved oxygen concentration in the SO. We present the first results obtained from a dissolved oxygen sensor added to Argos CTD-SRDL tags and deployed on 5 female elephant seals at Kerguelen. From October 2010 and October 2011, 742 oxygen profiles associated with temperature and salinity measurements were recorded. Whether a part of the data must be considered cautiously, especially because of offsets and temporal drifts of the sensors, the range of values recorded was consistent with a concomitant survey conducted from a research vessel (Keops-2 project). Once again, elephant seals reinforced the relationship between marine ecology and oceanography, delivering essential information about the water masses properties and the biological status of the Southern Ocean. But more than the presentation of a new stage of development in animal-borne instrumentation, this pilot study opens a new field of investigation in marine ecology and could be enlarged in a near future to other key marine predators, especially large fish species like swordfish, tuna or sharks, for which dissolved oxygen is expected to play a crucial role in distribution and behaviour.

Integrated ocean management as a strategy to meet rapid climate change: the Norwegian case.

PubMed

Hoel, Alf Håkon; Olsen, Erik

2012-02-01

The prospects of rapid climate change and the potential existence of tipping points in marine ecosystems where nonlinear change may result from them being overstepped, raises the question of strategies for coping with ecosystem change. There is broad agreement that the combined forces of climate change, pollution and increasing economic activities necessitates more comprehensive approaches to oceans management, centering on the concept of ecosystem-based oceans management. This article addresses the Norwegian experience in introducing integrated, ecosystem-based oceans management, emphasizing how climate change, seen as a major long-term driver of change in ecosystems, is addressed in management plans. Understanding the direct effects of climate variability and change on ecosystems and indirect effects on human activities is essential for adaptive planning to be useful in the long-term management of the marine environment.

Integrated (Meta) Genomic and Synthetic Biology Approaches to Develop New Biocatalysts

PubMed Central

Parages, María L.; Gutiérrez-Barranquero, José A.; Reen, F. Jerry; Dobson, Alan D.W.; O’Gara, Fergal

2016-01-01

In recent years, the marine environment has been the subject of increasing attention from biotechnological and pharmaceutical industries as a valuable and promising source of novel bioactive compounds. Marine biodiscovery programmes have begun to reveal the extent of novel compounds encoded within the enormous bacterial richness and diversity of the marine ecosystem. A combination of unique physicochemical properties and spatial niche-specific substrates, in wide-ranging and extreme habitats, underscores the potential of the marine environment to deliver on functionally novel biocatalytic activities. With the growing need for green alternatives to industrial processes, and the unique transformations which nature is capable of performing, marine biocatalysts have the potential to markedly improve current industrial pipelines. Furthermore, biocatalysts are known to possess chiral selectivity and specificity, a key focus of pharmaceutical drug design. In this review, we discuss how the explosion in genomics based sequence analysis, allied with parallel developments in synthetic and molecular biology, have the potential to fast-track the discovery and subsequent improvement of a new generation of marine biocatalysts. PMID:27007381

Evolutionary potential of marine phytoplankton under ocean acidification.

PubMed

Collins, Sinéad; Rost, Björn; Rynearson, Tatiana A

2014-01-01

Marine phytoplankton have many obvious characters, such as rapid cell division rates and large population sizes, that give them the capacity to evolve in response to global change on timescales of weeks, months or decades. However, few studies directly investigate if this adaptive potential is likely to be realized. Because of this, evidence of to whether and how marine phytoplankton may evolve in response to global change is sparse. Here, we review studies that help predict evolutionary responses to global change in marine phytoplankton. We find limited support from experimental evolution that some taxa of marine phytoplankton may adapt to ocean acidification, and strong indications from studies of variation and structure in natural populations that selection on standing genetic variation is likely. Furthermore, we highlight the large body of literature on plastic responses to ocean acidification available, and evolutionary theory that may be used to link plastic and evolutionary responses. Because of the taxonomic breadth spanned by marine phytoplankton, and the diversity of roles they fill in ocean ecosystems and biogeochemical cycles, we stress the necessity of treating taxa or functional groups individually.

Post-glacial redistribution and shifts in productivity of giant kelp forests

PubMed Central

Graham, Michael H.; Kinlan, Brian P.; Grosberg, Richard K.

2010-01-01

Quaternary glacial–interglacial cycles create lasting biogeographic, demographic and genetic effects on ecosystems, yet the ecological effects of ice ages on benthic marine communities are unknown. We analysed long-term datasets to develop a niche-based model of southern Californian giant kelp (Macrocystis pyrifera) forest distribution as a function of oceanography and geomorphology, and synthesized palaeo-oceanographic records to show that late Quaternary climate change probably drove high millennial variability in the distribution and productivity of this foundation species. Our predictions suggest that kelp forest biomass increased up to threefold from the glacial maximum to the mid-Holocene, then rapidly declined by 40–70 per cent to present levels. The peak in kelp forest productivity would have coincided with the earliest coastal archaeological sites in the New World. Similar late Quaternary changes in kelp forest distribution and productivity probably occurred in coastal upwelling systems along active continental margins worldwide, which would have resulted in complex shifts in the relative productivity of terrestrial and marine components of coastal ecosystems. PMID:19846450

A practical guide to the application of the IUCN Red List of Ecosystems criteria

PubMed Central

Rodríguez, Jon Paul; Keith, David A.; Rodríguez-Clark, Kathryn M.; Murray, Nicholas J.; Nicholson, Emily; Regan, Tracey J.; Miller, Rebecca M.; Barrow, Edmund G.; Bland, Lucie M.; Boe, Kaia; Brooks, Thomas M.; Oliveira-Miranda, María A.; Spalding, Mark; Wit, Piet

2015-01-01

The newly developed IUCN Red List of Ecosystems is part of a growing toolbox for assessing risks to biodiversity, which addresses ecosystems and their functioning. The Red List of Ecosystems standard allows systematic assessment of all freshwater, marine, terrestrial and subterranean ecosystem types in terms of their global risk of collapse. In addition, the Red List of Ecosystems categories and criteria provide a technical base for assessments of ecosystem status at the regional, national, or subnational level. While the Red List of Ecosystems criteria were designed to be widely applicable by scientists and practitioners, guidelines are needed to ensure they are implemented in a standardized manner to reduce epistemic uncertainties and allow robust comparisons among ecosystems and over time. We review the intended application of the Red List of Ecosystems assessment process, summarize ‘best-practice’ methods for ecosystem assessments and outline approaches to ensure operational rigour of assessments. The Red List of Ecosystems will inform priority setting for ecosystem types worldwide, and strengthen capacity to report on progress towards the Aichi Targets of the Convention on Biological Diversity. When integrated with other IUCN knowledge products, such as the World Database of Protected Areas/Protected Planet, Key Biodiversity Areas and the IUCN Red List of Threatened Species, the Red List of Ecosystems will contribute to providing the most complete global measure of the status of biodiversity yet achieved. PMID:25561664

Microbial gene functions enriched in the Deepwater Horizon deep-sea oil plume

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, Z.; Deng, Y.; Nostrand, J.D. Van

2011-06-15

The Deepwater Horizon oil spill in the Gulf of Mexico is the deepest and largest offshore spill in U.S. history and its impacts on marine ecosystems are largely unknown. Here, we showed that the microbial community functional composition and structure were dramatically altered in a deep-sea oil plume resulting from the spill. A variety of metabolic genes involved in both aerobic and anaerobic hydrocarbon degradation were highly enriched in the plume compared to outside the plume, indicating a great potential for intrinsic bioremediation or natural attenuation in the deep-sea. Various other microbial functional genes relevant to carbon, nitrogen, phosphorus, sulfurmore » and iron cycling, metal resistance, and bacteriophage replication were also enriched in the plume. Together, these results suggest that the indigenous marine microbial communities could play a significant role in biodegradation of oil spills in deep-sea environments.« less

The Environmental Context of Gastropods on Western Laurentia (Basin and Range Province) during the Great Ordovician Biodiversification Event

ERIC Educational Resources Information Center

Dahl, Robyn Mieko

2015-01-01

Gastropods are a major component of modern marine ecosystems and can be found in nearly every type of marine ecosystem. They experienced their first notable radiation during the Great Ordovician Biodiversification Event (~470 Ma), during which their diversity tripled. This study examines the gastropod assemblage preserved in the Basin and Range…

Ocean acidification and its potential effects on marine ecosystems.

PubMed

Guinotte, John M; Fabry, Victoria J

2008-01-01

Ocean acidification is rapidly changing the carbonate system of the world oceans. Past mass extinction events have been linked to ocean acidification, and the current rate of change in seawater chemistry is unprecedented. Evidence suggests that these changes will have significant consequences for marine taxa, particularly those that build skeletons, shells, and tests of biogenic calcium carbonate. Potential changes in species distributions and abundances could propagate through multiple trophic levels of marine food webs, though research into the long-term ecosystem impacts of ocean acidification is in its infancy. This review attempts to provide a general synthesis of known and/or hypothesized biological and ecosystem responses to increasing ocean acidification. Marine taxa covered in this review include tropical reef-building corals, cold-water corals, crustose coralline algae, Halimeda, benthic mollusks, echinoderms, coccolithophores, foraminifera, pteropods, seagrasses, jellyfishes, and fishes. The risk of irreversible ecosystem changes due to ocean acidification should enlighten the ongoing CO(2) emissions debate and make it clear that the human dependence on fossil fuels must end quickly. Political will and significant large-scale investment in clean-energy technologies are essential if we are to avoid the most damaging effects of human-induced climate change, including ocean acidification.

Edutourism Taka Bonerate National Park through Scientific Approach to Improve Student Learning Outcomes

NASA Astrophysics Data System (ADS)

Hayati, R. S.

2017-02-01

This research aim is develop the potential of Taka Bonerate National Park as learning resources through edutourism with scientific approach to improve student learning outcomes. Focus of student learning outcomes are students psychomotor abilities and comprehension on Biodiversity of Marine Biota, Corals Ecosystem, and Conservation topics. The edutourism development products are teacher manual, edutourism worksheet, material booklet, guide’s manual, and Taka Bonerate National Park governor manual. The method to develop edutourism products is ADDIE research and development model that consist of analysis, design, development and production, implementation, and evaluation step. The subjects in the implementation step were given a pretest and posttest and observation sheet to see the effect of edutourism Taka Bonerate National Park through scientific approach to student learning outcomes on Biodiversity of Marine Biota, Corals Ecosystem, and Conservation topics. The data were analyzed qualitative descriptively. The research result is edutourism Taka Bonerate National Park through scientific approach can improve students learning outcomes on Biodiversity of Marine Biota, Corals Ecosystem, and Conservation topics. Edutourism Taka Bonerate National Park can be an alternative of learning method on Biodiversity of Marine Biota, Corals Ecosystem, and Conservation topics.

Climate warming, marine protected areas and the ocean-scale integrity of coral reef ecosystems.

PubMed

Graham, Nicholas A J; McClanahan, Tim R; MacNeil, M Aaron; Wilson, Shaun K; Polunin, Nicholas V C; Jennings, Simon; Chabanet, Pascale; Clark, Susan; Spalding, Mark D; Letourneur, Yves; Bigot, Lionel; Galzin, René; Ohman, Marcus C; Garpe, Kajsa C; Edwards, Alasdair J; Sheppard, Charles R C

2008-08-27

Coral reefs have emerged as one of the ecosystems most vulnerable to climate variation and change. While the contribution of a warming climate to the loss of live coral cover has been well documented across large spatial and temporal scales, the associated effects on fish have not. Here, we respond to recent and repeated calls to assess the importance of local management in conserving coral reefs in the context of global climate change. Such information is important, as coral reef fish assemblages are the most species dense vertebrate communities on earth, contributing critical ecosystem functions and providing crucial ecosystem services to human societies in tropical countries. Our assessment of the impacts of the 1998 mass bleaching event on coral cover, reef structural complexity, and reef associated fishes spans 7 countries, 66 sites and 26 degrees of latitude in the Indian Ocean. Using Bayesian meta-analysis we show that changes in the size structure, diversity and trophic composition of the reef fish community have followed coral declines. Although the ocean scale integrity of these coral reef ecosystems has been lost, it is positive to see the effects are spatially variable at multiple scales, with impacts and vulnerability affected by geography but not management regime. Existing no-take marine protected areas still support high biomass of fish, however they had no positive affect on the ecosystem response to large-scale disturbance. This suggests a need for future conservation and management efforts to identify and protect regional refugia, which should be integrated into existing management frameworks and combined with policies to improve system-wide resilience to climate variation and change.

Predicting interactions among fishing, ocean warming, and ocean acidification in a marine system with whole-ecosystem models.

PubMed

Griffith, Gary P; Fulton, Elizabeth A; Gorton, Rebecca; Richardson, Anthony J

2012-12-01

An important challenge for conservation is a quantitative understanding of how multiple human stressors will interact to mitigate or exacerbate global environmental change at a community or ecosystem level. We explored the interaction effects of fishing, ocean warming, and ocean acidification over time on 60 functional groups of species in the southeastern Australian marine ecosystem. We tracked changes in relative biomass within a coupled dynamic whole-ecosystem modeling framework that included the biophysical system, human effects, socioeconomics, and management evaluation. We estimated the individual, additive, and interactive effects on the ecosystem and for five community groups (top predators, fishes, benthic invertebrates, plankton, and primary producers). We calculated the size and direction of interaction effects with an additive null model and interpreted results as synergistic (amplified stress), additive (no additional stress), or antagonistic (reduced stress). Individually, only ocean acidification had a negative effect on total biomass. Fishing and ocean warming and ocean warming with ocean acidification had an additive effect on biomass. Adding fishing to ocean warming and ocean acidification significantly changed the direction and magnitude of the interaction effect to a synergistic response on biomass. The interaction effect depended on the response level examined (ecosystem vs. community). For communities, the size, direction, and type of interaction effect varied depending on the combination of stressors. Top predator and fish biomass had a synergistic response to the interaction of all three stressors, whereas biomass of benthic invertebrates responded antagonistically. With our approach, we were able to identify the regional effects of fishing on the size and direction of the interacting effects of ocean warming and ocean acidification. ©2012 Society for Conservation Biology.

Bacterial taxa–area and distance–decay relationships in marine environments

PubMed Central

Zinger, L; Boetius, A; Ramette, A

2014-01-01

The taxa–area relationship (TAR) and the distance–decay relationship (DDR) both describe spatial turnover of taxa and are central patterns of biodiversity. Here, we compared TAR and DDR of bacterial communities across different marine realms and ecosystems at the global scale. To obtain reliable global estimates for both relationships, we quantified the poorly assessed effects of sequencing depth, rare taxa removal and number of sampling sites. Slope coefficients of bacterial TARs were within the range of those of plants and animals, whereas slope coefficients of bacterial DDR were much lower. Slope coefficients were mostly affected by removing rare taxa and by the number of sampling sites considered in the calculations. TAR and DDR slope coefficients were overestimated at sequencing depth <4000 sequences per sample. Noticeably, bacterial TAR and DDR patterns did not correlate with each other both within and across ecosystem types, suggesting that (i) TAR cannot be directly derived from DDR and (ii) TAR and DDR may be influenced by different ecological factors. Nevertheless, we found marine bacterial TAR and DDR to be steeper in ecosystems associated with high environmental heterogeneity or spatial isolation, namely marine sediments and coastal environments compared with pelagic ecosystems. Hence, our study provides information on macroecological patterns of marine bacteria, as well as methodological and conceptual insights, at a time when biodiversity surveys increasingly make use of high-throughput sequencing technologies. PMID:24460915

Image Fusion Applied to Satellite Imagery for the Improved Mapping and Monitoring of Coral Reefs: a Proposal

NASA Astrophysics Data System (ADS)

Gholoum, M.; Bruce, D.; Hazeam, S. Al

2012-07-01

A coral reef ecosystem, one of the most complex marine environmental systems on the planet, is defined as biologically diverse and immense. It plays an important role in maintaining a vast biological diversity for future generations and functions as an essential spawning, nursery, breeding and feeding ground for many kinds of marine species. In addition, coral reef ecosystems provide valuable benefits such as fisheries, ecological goods and services and recreational activities to many communities. However, this valuable resource is highly threatened by a number of environmental changes and anthropogenic impacts that can lead to reduced coral growth and production, mass coral mortality and loss of coral diversity. With the growth of these threats on coral reef ecosystems, there is a strong management need for mapping and monitoring of coral reef ecosystems. Remote sensing technology can be a valuable tool for mapping and monitoring of these ecosystems. However, the diversity and complexity of coral reef ecosystems, the resolution capabilities of satellite sensors and the low reflectivity of shallow water increases the difficulties to identify and classify its features. This paper reviews the methods used in mapping and monitoring coral reef ecosystems. In addition, this paper proposes improved methods for mapping and monitoring coral reef ecosystems based on image fusion techniques. This image fusion techniques will be applied to satellite images exhibiting high spatial and low to medium spectral resolution with images exhibiting low spatial and high spectral resolution. Furthermore, a new method will be developed to fuse hyperspectral imagery with multispectral imagery. The fused image will have a large number of spectral bands and it will have all pairs of corresponding spatial objects. This will potentially help to accurately classify the image data. Accuracy assessment use ground truth will be performed for the selected methods to determine the quality of the information derived from image classification. The research will be applied to the Kuwait's southern coral reefs: Kubbar and Um Al-Maradim.

Large-Scale Variation in Combined Impacts of Canopy Loss and Disturbance on Community Structure and Ecosystem Functioning

PubMed Central

Crowe, Tasman P.; Cusson, Mathieu; Bulleri, Fabio; Davoult, Dominique; Arenas, Francisco; Aspden, Rebecca; Benedetti-Cecchi, Lisandro; Bevilacqua, Stanislao; Davidson, Irvine; Defew, Emma; Fraschetti, Simonetta; Golléty, Claire; Griffin, John N.; Herkül, Kristjan; Kotta, Jonne; Migné, Aline; Molis, Markus; Nicol, Sophie K.; Noël, Laure M-L J.; Pinto, Isabel Sousa; Valdivia, Nelson; Vaselli, Stefano; Jenkins, Stuart R.

2013-01-01

Ecosystems are under pressure from multiple human disturbances whose impact may vary depending on environmental context. We experimentally evaluated variation in the separate and combined effects of the loss of a key functional group (canopy algae) and physical disturbance on rocky shore ecosystems at nine locations across Europe. Multivariate community structure was initially affected (during the first three to six months) at six locations but after 18 months, effects were apparent at only three. Loss of canopy caused increases in cover of non-canopy algae in the three locations in southern Europe and decreases in some northern locations. Measures of ecosystem functioning (community respiration, gross primary productivity, net primary productivity) were affected by loss of canopy at five of the six locations for which data were available. Short-term effects on community respiration were widespread, but effects were rare after 18 months. Functional changes corresponded with changes in community structure and/or species richness at most locations and times sampled, but no single aspect of biodiversity was an effective predictor of longer-term functional changes. Most ecosystems studied were able to compensate in functional terms for impacts caused by indiscriminate physical disturbance. The only consistent effect of disturbance was to increase cover of non-canopy species. Loss of canopy algae temporarily reduced community resistance to disturbance at only two locations and at two locations actually increased resistance. Resistance to disturbance-induced changes in gross primary productivity was reduced by loss of canopy algae at four locations. Location-specific variation in the effects of the same stressors argues for flexible frameworks for the management of marine environments. These results also highlight the need to analyse how species loss and other stressors combine and interact in different environmental contexts. PMID:23799082

Large-scale variation in combined impacts of canopy loss and disturbance on community structure and ecosystem functioning.

PubMed

Crowe, Tasman P; Cusson, Mathieu; Bulleri, Fabio; Davoult, Dominique; Arenas, Francisco; Aspden, Rebecca; Benedetti-Cecchi, Lisandro; Bevilacqua, Stanislao; Davidson, Irvine; Defew, Emma; Fraschetti, Simonetta; Golléty, Claire; Griffin, John N; Herkül, Kristjan; Kotta, Jonne; Migné, Aline; Molis, Markus; Nicol, Sophie K; Noël, Laure M-L J; Pinto, Isabel Sousa; Valdivia, Nelson; Vaselli, Stefano; Jenkins, Stuart R

2013-01-01

Ecosystems are under pressure from multiple human disturbances whose impact may vary depending on environmental context. We experimentally evaluated variation in the separate and combined effects of the loss of a key functional group (canopy algae) and physical disturbance on rocky shore ecosystems at nine locations across Europe. Multivariate community structure was initially affected (during the first three to six months) at six locations but after 18 months, effects were apparent at only three. Loss of canopy caused increases in cover of non-canopy algae in the three locations in southern Europe and decreases in some northern locations. Measures of ecosystem functioning (community respiration, gross primary productivity, net primary productivity) were affected by loss of canopy at five of the six locations for which data were available. Short-term effects on community respiration were widespread, but effects were rare after 18 months. Functional changes corresponded with changes in community structure and/or species richness at most locations and times sampled, but no single aspect of biodiversity was an effective predictor of longer-term functional changes. Most ecosystems studied were able to compensate in functional terms for impacts caused by indiscriminate physical disturbance. The only consistent effect of disturbance was to increase cover of non-canopy species. Loss of canopy algae temporarily reduced community resistance to disturbance at only two locations and at two locations actually increased resistance. Resistance to disturbance-induced changes in gross primary productivity was reduced by loss of canopy algae at four locations. Location-specific variation in the effects of the same stressors argues for flexible frameworks for the management of marine environments. These results also highlight the need to analyse how species loss and other stressors combine and interact in different environmental contexts.

European seaweeds under pressure: Consequences for communities and ecosystem functioning

NASA Astrophysics Data System (ADS)

Mineur, Frédéric; Arenas, Francisco; Assis, Jorge; Davies, Andrew J.; Engelen, Aschwin H.; Fernandes, Francisco; Malta, Erik-jan; Thibaut, Thierry; Van Nguyen, Tu; Vaz-Pinto, Fátima; Vranken, Sofie; Serrão, Ester A.; De Clerck, Olivier

2015-04-01

Seaweed assemblages represent the dominant autotrophic biomass in many coastal environments, playing a central structural and functional role in several ecosystems. In Europe, seaweed assemblages are highly diverse systems. The combined seaweed flora of different European regions hold around 1550 species (belonging to nearly 500 genera), with new species continuously uncovered, thanks to the emergence of molecular tools. In this manuscript we review the effects of global and local stressors on European seaweeds, their communities, and ecosystem functioning. Following a brief review on the present knowledge on European seaweed diversity and distribution, and the role of seaweed communities in biodiversity and ecosystem functioning, we discuss the effects of biotic homogenization (invasive species) and global climate change (shifts in bioclimatic zones and ocean acidification) on the distribution of individual species and their effect on the structure and functioning of seaweed communities. The arrival of new introduced species (that already account for 5-10% of the European seaweeds) and the regional extirpation of native species resulting from oceans' climate change are creating new diversity scenarios with undetermined functional consequences. Anthropogenic local stressors create additional disruption often altering dramatically assemblage's structure. Hence, we discuss ecosystem level effects of such stressors like harvesting, trampling, habitat modification, overgrazing and eutrophication that impact coastal communities at local scales. Last, we conclude by highlighting significant knowledge gaps that need to be addressed to anticipate the combined effects of global and local stressors on seaweed communities. With physical and biological changes occurring at unexpected pace, marine phycologists should now integrate and join their research efforts to be able to contribute efficiently for the conservation and management of coastal systems.

Experimenting with ecosystem interaction networks in search of threshold potentials in real-world marine ecosystems.

PubMed

Thrush, Simon F; Hewitt, Judi E; Parkes, Samantha; Lohrer, Andrew M; Pilditch, Conrad; Woodin, Sarah A; Wethey, David S; Chiantore, Mariachiara; Asnaghi, Valentina; De Juan, Silvia; Kraan, Casper; Rodil, Ivan; Savage, Candida; Van Colen, Carl

2014-06-01

Thresholds profoundly affect our understanding and management of ecosystem dynamics, but we have yet to develop practical techniques to assess the risk that thresholds will be crossed. Combining ecological knowledge of critical system interdependencies with a large-scale experiment, we tested for breaks in the ecosystem interaction network to identify threshold potential in real-world ecosystem dynamics. Our experiment with the bivalves Macomona liliana and Austrovenus stutchburyi on marine sandflats in New Zealand demonstrated that reductions in incident sunlight changed the interaction network between sediment biogeochemical fluxes, productivity, and macrofauna. By demonstrating loss of positive feedbacks and changes in the architecture of the network, we provide mechanistic evidence that stressors lead to break points in dynamics, which theory predicts predispose a system to a critical transition.

The Relevance of Marine Chemical Ecology to Plankton and Ecosystem Function: An Emerging Field

PubMed Central

Ianora, Adrianna; Bentley, Matthew G.; Caldwell, Gary S.; Casotti, Raffaella; Cembella, Allan D.; Engström-Öst, Jonna; Halsband, Claudia; Sonnenschein, Eva; Legrand, Catherine; Llewellyn, Carole A.; Paldavičienë, Aistë; Pilkaityte, Renata; Pohnert, Georg; Razinkovas, Arturas; Romano, Giovanna; Tillmann, Urban; Vaiciute, Diana

2011-01-01

Marine chemical ecology comprises the study of the production and interaction of bioactive molecules affecting organism behavior and function. Here we focus on bioactive compounds and interactions associated with phytoplankton, particularly bloom-forming diatoms, prymnesiophytes and dinoflagellates. Planktonic bioactive metabolites are structurally and functionally diverse and some may have multiple simultaneous functions including roles in chemical defense (antipredator, allelopathic and antibacterial compounds), and/or cell-to-cell signaling (e.g., polyunsaturated aldehydes (PUAs) of diatoms). Among inducible chemical defenses in response to grazing, there is high species-specific variability in the effects on grazers, ranging from severe physical incapacitation and/or death to no apparent physiological response, depending on predator susceptibility and detoxification capability. Most bioactive compounds are present in very low concentrations, in both the producing organism and the surrounding aqueous medium. Furthermore, bioactivity may be subject to synergistic interactions with other natural and anthropogenic environmental toxicants. Most, if not all phycotoxins are classic secondary metabolites, but many other bioactive metabolites are simple molecules derived from primary metabolism (e.g., PUAs in diatoms, dimethylsulfoniopropionate (DMSP) in prymnesiophytes). Producing cells do not seem to suffer physiological impact due to their synthesis. Functional genome sequence data and gene expression analysis will provide insights into regulatory and metabolic pathways in producer organisms, as well as identification of mechanisms of action in target organisms. Understanding chemical ecological responses to environmental triggers and chemically-mediated species interactions will help define crucial chemical and molecular processes that help maintain biodiversity and ecosystem functionality. PMID:22131962

Shark baselines and the conservation role of remote coral reef ecosystems

PubMed Central

Ferretti, Francesco; Curnick, David; Liu, Keli; Romanov, Evgeny V.; Block, Barbara A.

2018-01-01

Scientific monitoring has recorded only a recent fraction of the oceans’ alteration history. This biases our understanding of marine ecosystems. Remote coral reef ecosystems are often considered pristine because of high shark abundance. However, given the long history and global nature of fishing, sharks’ vulnerability, and the ecological consequences of shark declines, these states may not be natural. In the Chagos archipelago, one of the remotest coral reef systems on the planet, protected by a very large marine reserve, we integrated disparate fisheries and scientific survey data to reconstruct baselines and long-term population trajectories of two dominant sharks. In 2012, we estimated 571,310 gray reef and 31,693 silvertip sharks, about 79 and 7% of their baseline levels. These species were exploited longer and more intensively than previously thought and responded to fishing and protection with variable and compensatory population trajectories. Our approach highlights the value of integrative and historical analyses to evaluate large marine ecosystems currently considered pristine. PMID:29532033

Deep-water longline fishing has reduced impact on Vulnerable Marine Ecosystems

PubMed Central

Pham, Christopher K.; Diogo, Hugo; Menezes, Gui; Porteiro, Filipe; Braga-Henriques, Andreia; Vandeperre, Frederic; Morato, Telmo

2014-01-01

Bottom trawl fishing threatens deep-sea ecosystems, modifying the seafloor morphology and its physical properties, with dramatic consequences on benthic communities. Therefore, the future of deep-sea fishing relies on alternative techniques that maintain the health of deep-sea ecosystems and tolerate appropriate human uses of the marine environment. In this study, we demonstrate that deep-sea bottom longline fishing has little impact on vulnerable marine ecosystems, reducing bycatch of cold-water corals and limiting additional damage to benthic communities. We found that slow-growing vulnerable species are still common in areas subject to more than 20 years of longlining activity and estimate that one deep-sea bottom trawl will have a similar impact to 296–1,719 longlines, depending on the morphological complexity of the impacted species. Given the pronounced differences in the magnitude of disturbances coupled with its selectivity and low fuel consumption, we suggest that regulated deep-sea longlining can be an alternative to deep-sea bottom trawling. PMID:24776718

Trophic cascades triggered by overfishing reveal possible mechanisms of ecosystem regime shifts.

PubMed

Daskalov, Georgi M; Grishin, Alexander N; Rodionov, Sergei; Mihneva, Vesselina

2007-06-19

Large-scale transitions between alternative states in ecosystems are known as regime shifts. Once described as healthy and dominated by various marine predators, the Black Sea ecosystem by the late 20th century had experienced anthropogenic impacts such as heavy fishing, cultural eutrophication, and invasions by alien species. We studied changes related to these "natural experiments" to reveal the mechanisms of regime shifts. Two major shifts were detected, the first related to a depletion of marine predators and the second to an outburst of the alien comb jelly Mnemiopsis leidyi; both shifts were triggered by intense fishing resulting in system-wide trophic cascades. The complex nature of ecosystem responses to human activities calls for more elaborate approaches than currently provided by traditional environmental and fisheries management. This implies challenging existing practices and implementing explanatory models of ecosystem interactions that can better reconcile conservation and ecosystem management ideals.

Delayed recovery of non-marine tetrapods after the end-Permian mass extinction tracks global carbon cycle

PubMed Central

Irmis, Randall B.; Whiteside, Jessica H.

2012-01-01

During the end-Permian mass extinction, marine ecosystems suffered a major drop in diversity, which was maintained throughout the Early Triassic until delayed recovery during the Middle Triassic. This depressed diversity in the Early Triassic correlates with multiple major perturbations to the global carbon cycle, interpreted as either intrinsic ecosystem or external palaeoenvironmental effects. In contrast, the terrestrial record of extinction and recovery is less clear; the effects and magnitude of the end-Permian extinction on non-marine vertebrates are particularly controversial. We use specimen-level data from southern Africa and Russia to investigate the palaeodiversity dynamics of non-marine tetrapods across the Permo-Triassic boundary by analysing sample-standardized generic richness, evenness and relative abundance. In addition, we investigate the potential effects of sampling, geological and taxonomic biases on these data. Our analyses demonstrate that non-marine tetrapods were severely affected by the end-Permian mass extinction, and that these assemblages did not begin to recover until the Middle Triassic. These data are congruent with those from land plants and marine invertebrates. Furthermore, they are consistent with the idea that unstable low-diversity post-extinction ecosystems were subject to boom–bust cycles, reflected in multiple Early Triassic perturbations of the carbon cycle. PMID:22031757

Ecosystem Vulnerability Review: Proposal of an Interdisciplinary Ecosystem Assessment Approach

NASA Astrophysics Data System (ADS)

Weißhuhn, Peter; Müller, Felix; Wiggering, Hubert

2018-06-01

To safeguard the sustainable use of ecosystems and their services, early detection of potentially damaging changes in functional capabilities is needed. To support a proper ecosystem management, the analysis of an ecosystem's vulnerability provide information on its weaknesses as well as on its capacity to recover after suffering an impact. However, the application of the vulnerability concept to ecosystems is still an emerging topic. After providing background on the vulnerability concept, we summarize existing ecosystem vulnerability research on the basis of a systematic literature review with a special focus on ecosystem type, disciplinary background, and more detailed definition of the ecosystem vulnerability components. Using the Web of ScienceTM Core Collection, we overviewed the literature from 1991 onwards but used the 5 years from 2011 to 2015 for an in-depth analysis, including 129 articles. We found that ecosystem vulnerability analysis has been applied most notably in conservation biology, climate change research, and ecological risk assessments, pinpointing a limited spreading across the environmental sciences. It occurred primarily within marine and freshwater ecosystems. To avoid confusion, we recommend using the unambiguous term ecosystem vulnerability rather than ecological, environmental, population, or community vulnerability. Further, common ground has been identified, on which to define the ecosystem vulnerability components exposure, sensitivity, and adaptive capacity. We propose a framework for ecosystem assessments that coherently connects the concepts of vulnerability, resilience, and adaptability as different ecosystem responses. A short outlook on the possible operationalization of the concept by ecosystem vulnerabilty indices, and a conclusion section complete the review.

Ecosystem Vulnerability Review: Proposal of an Interdisciplinary Ecosystem Assessment Approach.

PubMed

Weißhuhn, Peter; Müller, Felix; Wiggering, Hubert

2018-06-01

To safeguard the sustainable use of ecosystems and their services, early detection of potentially damaging changes in functional capabilities is needed. To support a proper ecosystem management, the analysis of an ecosystem's vulnerability provide information on its weaknesses as well as on its capacity to recover after suffering an impact. However, the application of the vulnerability concept to ecosystems is still an emerging topic. After providing background on the vulnerability concept, we summarize existing ecosystem vulnerability research on the basis of a systematic literature review with a special focus on ecosystem type, disciplinary background, and more detailed definition of the ecosystem vulnerability components. Using the Web of Science TM Core Collection, we overviewed the literature from 1991 onwards but used the 5 years from 2011 to 2015 for an in-depth analysis, including 129 articles. We found that ecosystem vulnerability analysis has been applied most notably in conservation biology, climate change research, and ecological risk assessments, pinpointing a limited spreading across the environmental sciences. It occurred primarily within marine and freshwater ecosystems. To avoid confusion, we recommend using the unambiguous term ecosystem vulnerability rather than ecological, environmental, population, or community vulnerability. Further, common ground has been identified, on which to define the ecosystem vulnerability components exposure, sensitivity, and adaptive capacity. We propose a framework for ecosystem assessments that coherently connects the concepts of vulnerability, resilience, and adaptability as different ecosystem responses. A short outlook on the possible operationalization of the concept by ecosystem vulnerabilty indices, and a conclusion section complete the review.

Recent advances in plant-herbivore interactions

PubMed Central

Burkepile, Deron E.; Parker, John D.

2017-01-01

Plant-herbivore interactions shape community dynamics across marine, freshwater, and terrestrial habitats. From amphipods to elephants and from algae to trees, plant-herbivore relationships are the crucial link generating animal biomass (and human societies) from mere sunlight. These interactions are, thus, pivotal to understanding the ecology and evolution of virtually any ecosystem. Here, we briefly highlight recent advances in four areas of plant-herbivore interactions: (1) plant defense theory, (2) herbivore diversity and ecosystem function, (3) predation risk aversion and herbivory, and (4) how a changing climate impacts plant-herbivore interactions. Recent advances in plant defense theory, for example, highlight how plant life history and defense traits affect and are affected by multiple drivers, including enemy pressure, resource availability, and the local plant neighborhood, resulting in trait-mediated feedback loops linking trophic interactions with ecosystem nutrient dynamics. Similarly, although the positive effect of consumer diversity on ecosystem function has long been recognized, recent advances using DNA barcoding to elucidate diet, and Global Positioning System/remote sensing to determine habitat selection and impact, have shown that herbivore communities are probably even more functionally diverse than currently realized. Moreover, although most diversity-function studies continue to emphasize plant diversity, herbivore diversity may have even stronger impacts on ecosystem multifunctionality. Recent studies also highlight the role of risk in plant-herbivore interactions, and risk-driven trophic cascades have emerged as landscape-scale patterns in a variety of ecosystems. Perhaps not surprisingly, many plant-herbivore interactions are currently being altered by climate change, which affects plant growth rates and resource allocation, expression of chemical defenses, plant phenology, and herbivore metabolism and behavior. Finally, we conclude by noting that although the field is advancing rapidly, the world is changing even more rapidly, challenging our ability to manage these pivotal links in the food chain. PMID:28232868

The role of sustained observations in tracking impacts of environmental change on marine biodiversity and ecosystems

PubMed Central

Mieszkowska, N.; Sugden, H.; Firth, L. B.; Hawkins, S. J.

2014-01-01

Marine biodiversity currently faces unprecedented threats from multiple pressures arising from human activities. Global drivers such as climate change and ocean acidification interact with regional eutrophication, exploitation of commercial fish stocks and localized pressures including pollution, coastal development and the extraction of aggregates and fuel, causing alteration and degradation of habitats and communities. Segregating natural from anthropogenically induced change in marine ecosystems requires long-term, sustained observations of marine biota. In this review, we outline the history of biological recording in the coastal and shelf seas of the UK and Ireland and highlight where sustained observations have contributed new understanding of how anthropogenic activities have impacted on marine biodiversity. The contributions of sustained observations, from those collected at observatories, single station platforms and multiple-site programmes to the emergent field of multiple stressor impacts research, are discussed, along with implications for management and sustainable governance of marine resources in an era of unprecedented use of the marine environment. PMID:25157190

Vulnerability of intertropical littoral areas

NASA Astrophysics Data System (ADS)

Manighetti, Isabelle; De Wit, Rutger; Duvail, Stéphanie; Seyler, Patrick

2017-10-01

The coastal zone is of very high importance for human development and human wellbeing. Half of the global urban population lives in the coastal zone, where it has access to both continental and marine ecosystem services and to maritime transport. These urban populations coexist with rural and traditional coastal populations, some of which still possess good traditional ecological knowledge of the coastal ecosystems. Marine biodiversity and favourable environmental conditions sustain fisheries and aquaculture, represent a source of inspiration for humankind and provide numerous opportunities for recreation and tourism. In addition, coastal areas provide nursery functions for juvenile fish and invertebrates, which is important for the fish and crayfish stocks exploited offshore. Located at the interface between marine energy and continental processes, the coastal landscapes are dynamic environments. Nevertheless, the destruction of habitats and the increasing exploitation of the coastal zone represent serious threats to the ecosystems. Moreover, human land use and modifications in the watersheds have strong impacts on the coastal zone primarily by contributing to their pollution and nutrient over-enrichment. Damming and creation of reservoirs upstream also heavily modify the hydrology of the watersheds and often dramatically reduce the delivery of sediments to the coastal zone. In addition to these regional and local anthropogenic impacts, the coastal zone is vulnerable to global change among which sea level rise and climate change are particularly important drivers. Many coastal zones extend along giant faults and subduction zones, which makes them particularly exposed to earthquakes and tsunami hazards. Other forms of natural hazards are caused by hurricanes and cyclones that develop at sea and whose trajectories often hit the coastlines.

78 FR 49258 - Fisheries in the Western Pacific; Special Coral Reef Ecosystem Fishing Permit

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-13

... the Western Pacific; Special Coral Reef Ecosystem Fishing Permit AGENCY: National Marine Fisheries... Reef Ecosystem Fishing Permit that would authorize Kampachi Farms, LLC, to culture and harvest a coral...: NMFS proposes to issue a Special Coral Reef Ecosystem Fishing Permit to Kampachi Farms, LLC, consistent...

The potential role of habitat-forming seaweeds in modeling benthic ecosystem properties

NASA Astrophysics Data System (ADS)

Bustamante, María; Tajadura, Javier; Díez, Isabel; Saiz-Salinas, José Ignacio

2017-12-01

Canopy-forming seaweeds provide specific habitats with key ecological properties and are facing severe declines worldwide with unforeseeable consequences for ecosystem processes. Investigating the loss of such natural habitats in order to develop management strategies for conservation is a major challenge in marine ecological research. This study investigated the shallow rocky bottoms of the southern Bay of Biscay at two sampling times with a view to identifying the effect of canopy seaweed availability on the taxonomic and functional properties of invertebrate multivariate structure, abundance, density, diversity and evenness. The multivariate taxonomic and functional structure of assemblages changed significantly according to canopy availability in terms of taxa and functional groups abundance, but no substantial change was observed in composition. Biogenic habitat simplification resulted in a decrease in total invertebrate abundance and in taxonomic and functional density and diversity, whilst no effects were observed in taxonomic and functional evenness. Loss of canopy involved an impoverishment of the whole community particularly for epiphytic colonial sessile suspension-feeders, but it also extended to non-epiphytic forms. Our results emphasize the importance of canopy decline as a major driver of changes in benthic ecosystem properties and highlight that biogenic space provided by canopy is a limiting resource for the development of rocky subtidal invertebrates.

Effects of olive oil wastes on river basins and an oligotrophic coastal marine ecosystem: a case study in Greece.

PubMed

Pavlidou, A; Anastasopoulou, E; Dassenakis, Μ; Hatzianestis, I; Paraskevopoulou, V; Simboura, N; Rousselaki, E; Drakopoulou, P

2014-11-01

This work aims to contribute to the knowledge of the impacts of olive oil waste discharge to freshwater and oligotrophic marine environments, since the ecological impact of olive oil wastes in riverine and coastal marine ecosystems, which are the final repositories of the pollutants, is a great environmental problem on a global scale, mostly concerning all the Mediterranean countries with olive oil production. Messinia, in southwestern Greece, is one of the greatest olive oil production areas in Europe. During the last decade around 1.4×10(6)tons of olive oil mill wastewater has been disposed in the rivers of Messinia and finally entered the marine ecosystem of Messiniakos gulf. The pollution from olive oil mill wastewater in the main rivers of Messinia and the oligotrophic coastal zone of Messiniakos gulf and its effects on marine organisms were evaluated, before, during and after the olive oil production period. Elevated amounts of phenols (36.2-178 mg L(-1)) and high concentrations of ammonium (7.29-18.9 mmol L(-1)) and inorganic phosphorus (0.5-7.48 mmol L(-1)) were measured in small streams where the liquid disposals from several olive oil industries were gathered before their discharge in the major rivers of Messinia. The large number of olive oil units has downgraded the riverine and marine ecosystems during the productive period and a period more than five months is needed for the recovery of the ecosystem. Statistical analysis showed that the enrichment of freshwater and the coastal zone of Messiniakos gulf in ammonia, nitrite, phenols, total organic carbon, copper, manganese and nickel was directly correlated with the wastes from olive oil. Toxicity tests using 24h LC50 Palaemonidae shrimp confirm that olive mill wastewater possesses very high toxicity in the aquatic environment. Copyright © 2014 Elsevier B.V. All rights reserved.

Climate change impacts on wildlife in a High Arctic archipelago - Svalbard, Norway.

PubMed

Descamps, Sébastien; Aars, Jon; Fuglei, Eva; Kovacs, Kit M; Lydersen, Christian; Pavlova, Olga; Pedersen, Åshild Ø; Ravolainen, Virve; Strøm, Hallvard

2017-02-01

The Arctic is warming more rapidly than other region on the planet, and the northern Barents Sea, including the Svalbard Archipelago, is experiencing the fastest temperature increases within the circumpolar Arctic, along with the highest rate of sea ice loss. These physical changes are affecting a broad array of resident Arctic organisms as well as some migrants that occupy the region seasonally. Herein, evidence of climate change impacts on terrestrial and marine wildlife in Svalbard is reviewed, with a focus on bird and mammal species. In the terrestrial ecosystem, increased winter air temperatures and concomitant increases in the frequency of 'rain-on-snow' events are one of the most important facets of climate change with respect to impacts on flora and fauna. Winter rain creates ice that blocks access to food for herbivores and synchronizes the population dynamics of the herbivore-predator guild. In the marine ecosystem, increases in sea temperature and reductions in sea ice are influencing the entire food web. These changes are affecting the foraging and breeding ecology of most marine birds and mammals and are associated with an increase in abundance of several temperate fish, seabird and marine mammal species. Our review indicates that even though a few species are benefiting from a warming climate, most Arctic endemic species in Svalbard are experiencing negative consequences induced by the warming environment. Our review emphasizes the tight relationships between the marine and terrestrial ecosystems in this High Arctic archipelago. Detecting changes in trophic relationships within and between these ecosystems requires long-term (multidecadal) demographic, population- and ecosystem-based monitoring, the results of which are necessary to set appropriate conservation priorities in relation to climate warming. © 2016 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

Grazer-induced transcriptomic and metabolomic response of the chain-forming diatom Skeletonema marinoi.

PubMed

Amato, Alberto; Sabatino, Valeria; Nylund, Göran M; Bergkvist, Johanna; Basu, Swaraj; Andersson, Mats X; Sanges, Remo; Godhe, Anna; Kiørboe, Thomas; Selander, Erik; Ferrante, Maria I

2018-06-01

Diatoms and copepods are main actors in marine food webs. The prey-predator interactions between them affect bloom dynamics, shape marine ecosystems and impact the energy transfer to higher trophic levels. Recently it has been demonstrated that the presence of grazers may affect the diatom prey beyond the direct effect of grazing. Here, we investigated the response of the chain-forming centric diatom Skeletonema marinoi to grazer cues, including changes in morphology, gene expression and metabolic profile. S. marinoi cells were incubated with Calanus finmarchicus or with Centropages typicus and in both cases responded by reducing the chain length, whereas changes in gene expression indicated an activation of stress response, changes in the lipid and nitrogen metabolism, in cell cycle regulation and in frustule formation. Transcripts linked to G protein-coupled receptors and to nitric oxide synthesis were differentially expressed suggesting involvement of these signalling transduction pathways in the response. Downregulation of a lipoxygenase in the transcriptomic data and of its products in the metabolomic data also indicate an involvement of oxylipins. Our data contribute to a better understanding of the gene function in diatoms, providing information on the nature of genes implicated in the interaction with grazers, a crucial process in marine ecosystems.

Overview of integrative tools and methods in assessing ecological integrity in estuarine and coastal systems worldwide.

PubMed

Borja, Angel; Bricker, Suzanne B; Dauer, Daniel M; Demetriades, Nicolette T; Ferreira, João G; Forbes, Anthony T; Hutchings, Pat; Jia, Xiaoping; Kenchington, Richard; Carlos Marques, João; Zhu, Changbo

2008-09-01

In recent years, several sets of legislation worldwide (Oceans Act in USA, Australia or Canada; Water Framework Directive or Marine Strategy in Europe, National Water Act in South Africa, etc.) have been developed in order to address ecological quality or integrity, within estuarine and coastal systems. Most such legislation seeks to define quality in an integrative way, by using several biological elements, together with physico-chemical and pollution elements. Such an approach allows assessment of ecological status at the ecosystem level ('ecosystem approach' or 'holistic approach' methodologies), rather than at species level (e.g. mussel biomonitoring or Mussel Watch) or just at chemical level (i.e. quality objectives) alone. Increasing attention has been paid to the development of tools for different physico-chemical or biological (phytoplankton, zooplankton, benthos, algae, phanerogams, fishes) elements of the ecosystems. However, few methodologies integrate all the elements into a single evaluation of a water body. The need for such integrative tools to assess ecosystem quality is very important, both from a scientific and stakeholder point of view. Politicians and managers need information from simple and pragmatic, but scientifically sound methodologies, in order to show to society the evolution of a zone (estuary, coastal area, etc.), taking into account human pressures or recovery processes. These approaches include: (i) multidisciplinarity, inherent in the teams involved in their implementation; (ii) integration of biotic and abiotic factors; (iii) accurate and validated methods in determining ecological integrity; and (iv) adequate indicators to follow the evolution of the monitored ecosystems. While some countries increasingly use the establishment of marine parks to conserve marine biodiversity and ecological integrity, there is awareness (e.g. in Australia) that conservation and management of marine ecosystems cannot be restricted to Marine Protected Areas but must include areas outside such reserves. This contribution reviews the current situation of integrative ecological assessment worldwide, by presenting several examples from each of the continents: Africa, Asia, Australia, Europe and North America.

Climate variability and the Icelandic marine ecosystem

NASA Astrophysics Data System (ADS)

Astthorsson, Olafur S.; Gislason, Astthor; Jonsson, Steingrimur

2007-11-01

This paper describes the main features of the Icelandic marine ecosystem and its response to climate variations during the 20th century. The physical oceanographic character and faunal composition in the southern and western parts of the Icelandic marine ecosystem are different from those in the northern and the eastern areas. The former areas are more or less continuously bathed by warm and saline Atlantic water while the latter are more variable and influenced by Atlantic, Arctic and even Polar water masses to different degrees. Mean annual primary production is higher in the Atlantic water than in the more variable waters north and east of Iceland, and higher closer to land than farther offshore. Similarly, zooplankton production is generally higher in the Atlantic water than in the waters north and east of Iceland. The main spawning grounds of most of the exploited fish stocks are in the Atlantic water south of the country while nursery grounds are off the north coast. In the recent years the total catch of fish and invertebrates has been in the range of 1.6-2.4 million ton. Capelin ( Mallotus villosus) is the most important pelagic stock and cod ( Gadus morhua) is by far the most important demersal fish stock. Whales are an important component of the Icelandic marine ecosystem, and Icelandic waters are an important habitat for some of the largest seabird populations in the Northeast Atlantic. In the waters to the north and east of Iceland, available information suggests the existence of a simple bottom-up controlled food chain from phytoplankton through Calanus, capelin and to cod. Less is known about the structure of the more complex southern part of the ecosystem. The Icelandic marine ecosystem is highly sensitive to climate variations as demonstrated by abundance and distribution changes of many species during the warm period in the 1930s, the cold period in the late 1960s and warming observed during the recent years. Some of these are highlighted in the paper.

75 FR 39638 - Fisheries of the Caribbean, Gulf of Mexico, and South Atlantic; Comprehensive Ecosystem-Based...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-07-12

...; Comprehensive Ecosystem-Based Amendment 1 for the South Atlantic Region; Correction AGENCY: National Marine... Comprehensive Ecosystem-Based Amendment 1 for the South Atlantic region that published in the Federal Register...

Environmental science. Rethinking the marine carbon cycle: factoring in the multifarious lifestyles of microbes.

PubMed

Worden, Alexandra Z; Follows, Michael J; Giovannoni, Stephen J; Wilken, Susanne; Zimmerman, Amy E; Keeling, Patrick J

2015-02-13

The profound influence of marine plankton on the global carbon cycle has been recognized for decades, particularly for photosynthetic microbes that form the base of ocean food chains. However, a comprehensive model of the carbon cycle is challenged by unicellular eukaryotes (protists) having evolved complex behavioral strategies and organismal interactions that extend far beyond photosynthetic lifestyles. As is also true for multicellular eukaryotes, these strategies and their associated physiological changes are difficult to deduce from genome sequences or gene repertoires—a problem compounded by numerous unknown function proteins. Here, we explore protistan trophic modes in marine food webs and broader biogeochemical influences. We also evaluate approaches that could resolve their activities, link them to biotic and abiotic factors, and integrate them into an ecosystems biology framework. Copyright © 2015, American Association for the Advancement of Science.

Arctic marine fishes and their fisheries in light of global change.

PubMed

Christiansen, Jørgen S; Mecklenburg, Catherine W; Karamushko, Oleg V

2014-02-01

In light of ocean warming and loss of Arctic sea ice, harvested marine fishes of boreal origin (and their fisheries) move poleward into yet unexploited parts of the Arctic seas. Industrial fisheries, already in place on many Arctic shelves, will radically affect the local fish species as they turn up as unprecedented bycatch. Arctic marine fishes are indispensable to ecosystem structuring and functioning, but they are still beyond credible assessment due to lack of basic biological data. The time for conservation actions is now, and precautionary management practices by the Arctic coastal states are needed to mitigate the impact of industrial fisheries in Arctic waters. We outline four possible conservation actions: scientific credibility, 'green technology', legitimate management and overarching coordination. © 2013 The Authors Global Change Biology Published by John Wiley & Sons Ltd.

Trophic models: What do we learn about Celtic Sea and Bay of Biscay ecosystems?

NASA Astrophysics Data System (ADS)

Moullec, Fabien; Gascuel, Didier; Bentorcha, Karim; Guénette, Sylvie; Robert, Marianne

2017-08-01

Trophic models are key tools to go beyond the single-species approaches used in stock assessments to adopt a more holistic view and implement the Ecosystem Approach to Fisheries Management (EAFM). This study aims to: (i) analyse the trophic functioning of the Celtic Sea and the Bay of Biscay, (ii) investigate ecosystem changes over the 1980-2013 period and, (iii) explore the response to management measures at the food web scale. Ecopath models were built for each ecosystem for years 1980 and 2013, and Ecosim models were fitted to time series data of biomass and catches. EcoTroph diagnosis showed that in both ecosystems, fishing pressure focuses on high trophic levels (TLs) and, to a lesser extent, on intermediate TLs. However, the interplay between local environmental conditions, species composition and ecosystem functioning could explain the different responses to fisheries management observed between these two contiguous ecosystems. Indeed, over the study period, the ecosystem's exploitation status has improved in the Bay of Biscay but not in the Celtic Sea. This improvement does not seem to be sufficient to achieve the objectives of an EAFM, as high trophic levels were still overexploited in 2013 and simulations conducted with Ecosim in the Bay of Biscay indicate that at current fishing effort the biomass will not be rebuilt by 2030. The ecosystem's response to a reduction in fishing mortality depends on which trophic levels receive protection. Reducing fishing mortality on pelagic fish, instead of on demersal fish, appears more efficient at maximising catch and total biomass and at conserving both top-predator and intermediate TLs. Such advice-oriented trophic models should be used on a regular basis to monitor the health status of marine food webs and analyse the trade-offs between multiple objectives in an ecosystem-based fisheries management context.

The Future of Marine Biogeochemistry, Ecosystems, and Societies

NASA Astrophysics Data System (ADS)

Bundy, Alida; Liu, Kon-Kee; Thomas, Helmuth

2013-05-01

The international project Integrated Marine Biogeochemistry and Ecosystem Research (IMBER) convenes an IMBIZO (a Zulu word meaning "a gathering") biennially, with a format of three concurrent, interacting workshops designed to synthesize information on topical research areas in marine science. IMBIZO III, held at the National Institute of Oceanography in Goa, India, focused on multidimensional approaches to challenges of global change in continental margins (CM), open ocean systems, and dependent human societies. More than 120 participants from 29 nations attended the meeting; the smaller workshop groups allowed in-depth discussions, and daily plenary sessions facilitated discussion among interdisciplinary experts.

Combining Ballast Water Exchange and Treatment To Maximize Prevention of Species Introductions to Freshwater Ecosystems.

PubMed

Briski, Elizabeta; Gollasch, Stephan; David, Matej; Linley, R Dallas; Casas-Monroy, Oscar; Rajakaruna, Harshana; Bailey, Sarah A

2015-08-18

The most effective way to manage species transfers is to prevent their introduction via vector regulation. Soon, international ships will be required to meet numeric ballast discharge standards using ballast water treatment (BWT) systems, and ballast water exchange (BWE), currently required by several countries, will be phased out. However, there are concerns that BWT systems may not function reliably in fresh and/or turbid water. A land-based evaluation of simulated "BWE plus BWT" versus "BWT alone" demonstrated potential benefits of combining BWE with BWT for protection of freshwater ecosystems. We conducted ship-based testing to compare the efficacy of "BWE plus BWT" versus "BWT alone" on voyages starting with freshwater ballast. We tested the hypotheses that there is an additional effect of "BWE plus BWT" compared to "BWT alone" on the reduction of plankton, and that taxa remaining after "BWE plus BWT" will be marine (low risk for establishment at freshwater recipient ports). Our study found that BWE has significant additional effect on the reduction of plankton, and this effect increases with initial abundance. As per expectations, "BWT alone" tanks contained higher risk freshwater or euryhaline taxa at discharge, while "BWE plus BWT" tanks contained mostly lower risk marine taxa unlikely to survive in recipient freshwater ecosystems.

Effects of exotic fish farms on bird communities in lake and marine ecosystems

NASA Astrophysics Data System (ADS)

Jiménez, Jaime E.; Arriagada, Aldo M.; Fontúrbel, Francisco E.; Camus, Patricio A.; Ávila-Thieme, M. Isidora

2013-08-01

Salmon farming is a widespread activity around the world, also known to promote diverse environmental effects on aquatic ecosystems. However, information regarding the impact of salmon farming on bird assemblages is notably scarce. We hypothesize that salmon farming, by providing food subsidies and physical structures to birds, will change their local community structure. To test this hypothesis, we conducted a seasonal monitoring of bird richness, abundance, and composition at paired salmon pen and control plots in two marine and two lake sites in southern Chile, from fall 2002 to summer 2004. Overall, salmon farming had no significant effects on species richness, but bird abundance was significantly and noticeably higher in salmon pens than in controls. Such aggregation was mainly accounted for by the trophic guilds of omnivores, diving piscivores, carrion eaters, and perching piscivores, but not by invertebrate feeders, herbivores, and surface feeders. Species composition was also significantly and persistently different between salmon pens and controls within each lake or marine locality. The patterns described above remained consistent across environment types and seasons indicating that salmon farming is changing the community structure of birds in both lake and marine habitats by promoting functional and aggregation responses, particularly by favoring species with broader niches. Such local patterns may thus anticipate potential threats from the ongoing expansion of the salmon industry to neighboring areas in Chile, resulting in regional changes of bird communities, toward a less diverse one and dominated by opportunistic, common, and generalist species such as gulls, vultures, and cormorants.

Effects of exotic fish farms on bird communities in lake and marine ecosystems.

PubMed

Jiménez, Jaime E; Arriagada, Aldo M; Fontúrbel, Francisco E; Camus, Patricio A; Avila-Thieme, M Isidora

2013-08-01

Salmon farming is a widespread activity around the world, also known to promote diverse environmental effects on aquatic ecosystems. However, information regarding the impact of salmon farming on bird assemblages is notably scarce. We hypothesize that salmon farming, by providing food subsidies and physical structures to birds, will change their local community structure. To test this hypothesis, we conducted a seasonal monitoring of bird richness, abundance, and composition at paired salmon pen and control plots in two marine and two lake sites in southern Chile, from fall 2002 to summer 2004. Overall, salmon farming had no significant effects on species richness, but bird abundance was significantly and noticeably higher in salmon pens than in controls. Such aggregation was mainly accounted for by the trophic guilds of omnivores, diving piscivores, carrion eaters, and perching piscivores, but not by invertebrate feeders, herbivores, and surface feeders. Species composition was also significantly and persistently different between salmon pens and controls within each lake or marine locality. The patterns described above remained consistent across environment types and seasons indicating that salmon farming is changing the community structure of birds in both lake and marine habitats by promoting functional and aggregation responses, particularly by favoring species with broader niches. Such local patterns may thus anticipate potential threats from the ongoing expansion of the salmon industry to neighboring areas in Chile, resulting in regional changes of bird communities, toward a less diverse one and dominated by opportunistic, common, and generalist species such as gulls, vultures, and cormorants.

Synthesis of Knowledge on Marine Biodiversity in European Seas: From Census to Sustainable Management

PubMed Central

Narayanaswamy, Bhavani E.

2013-01-01

The recently completed European Census of Marine Life, conducted within the framework of the global Census of Marine Life programme (2000–2010), markedly enhanced our understanding of marine biodiversity in European Seas, its importance within ecological systems, and the implications for human use. Here we undertake a synthesis of present knowledge of biodiversity in European Seas and identify remaining challenges that prevent sustainable management of marine biodiversity in one of the most exploited continents of the globe. Our analysis demonstrates that changes in faunal standing stock with depth depends on the size of the fauna, with macrofaunal abundance only declining with increasing water depth below 1000 m, whilst there was no obvious decrease in meiofauna with increasing depth. Species richness was highly variable for both deep water macro- and meio- fauna along latitudinal and longitudinal gradients. Nematode biodiversity decreased from the Atlantic into the Mediterranean whilst latitudinal related biodiversity patterns were similar for both faunal groups investigated, suggesting that the same environmental drivers were influencing the fauna. While climate change and habitat degradation are the most frequently implicated stressors affecting biodiversity throughout European Seas, quantitative understanding, both at individual and cumulative/synergistic level, of their influences are often lacking. Full identification and quantification of species, in even a single marine habitat, remains a distant goal, as we lack integrated data-sets to quantify these. While the importance of safeguarding marine biodiversity is recognised by policy makers, the lack of advanced understanding of species diversity and of a full survey of any single habitat raises huge challenges in quantifying change, and facilitating/prioritising habitat/ecosystem protection. Our study highlights a pressing requirement for more complete biodiversity surveys to be undertaken within contrasting habitats, together with investigations in biodiversity-ecosystem functioning links and identification of separate and synergistic/cumulative human-induced impacts on biodiversity. PMID:23527045

Synthesis of knowledge on marine biodiversity in European Seas: from census to sustainable management.

PubMed

Narayanaswamy, Bhavani E; Coll, Marta; Danovaro, Roberto; Davidson, Keith; Ojaveer, Henn; Renaud, Paul E

2013-01-01

The recently completed European Census of Marine Life, conducted within the framework of the global Census of Marine Life programme (2000-2010), markedly enhanced our understanding of marine biodiversity in European Seas, its importance within ecological systems, and the implications for human use. Here we undertake a synthesis of present knowledge of biodiversity in European Seas and identify remaining challenges that prevent sustainable management of marine biodiversity in one of the most exploited continents of the globe. Our analysis demonstrates that changes in faunal standing stock with depth depends on the size of the fauna, with macrofaunal abundance only declining with increasing water depth below 1000 m, whilst there was no obvious decrease in meiofauna with increasing depth. Species richness was highly variable for both deep water macro- and meio- fauna along latitudinal and longitudinal gradients. Nematode biodiversity decreased from the Atlantic into the Mediterranean whilst latitudinal related biodiversity patterns were similar for both faunal groups investigated, suggesting that the same environmental drivers were influencing the fauna. While climate change and habitat degradation are the most frequently implicated stressors affecting biodiversity throughout European Seas, quantitative understanding, both at individual and cumulative/synergistic level, of their influences are often lacking. Full identification and quantification of species, in even a single marine habitat, remains a distant goal, as we lack integrated data-sets to quantify these. While the importance of safeguarding marine biodiversity is recognised by policy makers, the lack of advanced understanding of species diversity and of a full survey of any single habitat raises huge challenges in quantifying change, and facilitating/prioritising habitat/ecosystem protection. Our study highlights a pressing requirement for more complete biodiversity surveys to be undertaken within contrasting habitats, together with investigations in biodiversity-ecosystem functioning links and identification of separate and synergistic/cumulative human-induced impacts on biodiversity.

Mixotrophy in the Marine Plankton

NASA Astrophysics Data System (ADS)

Stoecker, Diane K.; Hansen, Per Juel; Caron, David A.; Mitra, Aditee

2017-01-01

Mixotrophs are important components of the bacterioplankton, phytoplankton, microzooplankton, and (sometimes) zooplankton in coastal and oceanic waters. Bacterivory among the phytoplankton may be important for alleviating inorganic nutrient stress and may increase primary production in oligotrophic waters. Mixotrophic phytoflagellates and dinoflagellates are often dominant components of the plankton during seasonal stratification. Many of the microzooplankton grazers, including ciliates and Rhizaria, are mixotrophic owing to their retention of functional algal organelles or maintenance of algal endosymbionts. Phototrophy among the microzooplankton may increase gross growth efficiency and carbon transfer through the microzooplankton to higher trophic levels. Characteristic assemblages of mixotrophs are associated with warm, temperate, and cold seas and with stratification, fronts, and upwelling zones. Modeling has indicated that mixotrophy has a profound impact on marine planktonic ecosystems and may enhance primary production, biomass transfer to higher trophic levels, and the functioning of the biological carbon pump.

An underwater light attenuation scheme for marine ecosystem models.

PubMed

Penta, Bradley; Lee, Zhongping; Kudela, Raphael M; Palacios, Sherry L; Gray, Deric J; Jolliff, Jason K; Shulman, Igor G

2008-10-13

Simulation of underwater light is essential for modeling marine ecosystems. A new model of underwater light attenuation is presented and compared with previous models. In situ data collected in Monterey Bay, CA. during September 2006 are used for validation. It is demonstrated that while the new light model is computationally simple and efficient it maintains accuracy and flexibility. When this light model is incorporated into an ecosystem model, the correlation between modeled and observed coastal chlorophyll is improved over an eight-year time period. While the simulation of a deep chlorophyll maximum demonstrates the effect of the new model at depth.

Taking the Pulse of a Large Marine Ecosystem: An Inventory and Gap Analysis of Long-Term Recovery Monitoring Efforts in the Gulf of Mexico

NASA Astrophysics Data System (ADS)

Robbins, C.; Baldera, A.; Spies, R.; Love, M. S.

2016-02-01

Discharges of hydrocarbons into a large marine ecosystem can cause acute and sub-lethal effects, resulting in a recovery of populations or habitats that could take years, even decades. Recovery from oil spill impacts is complicated by the vagaries of a dynamic marine ecosystem. A major challenge and need is establishing and sustaining an interdisciplinary monitoring and research program capable of tracking oil spill impacts and resource recovery within the context of an ever changing, chronically stressed ecosystem. Ocean Conservancy undertook an assessment to identify and prioritize data collection activities for tracking the recovery of species and habitats impacted by the BP oil disaster in the Gulf of Mexico. We inventoried more than 700 discrete monitoring efforts in the Gulf, identified gaps in coverage for priority species, habitats and ecosystem drivers in space and time and mapped the footprints of active monitoring activities for ease of communication. We will present an overview of our methods and findings from the inventory and gap analysis and discuss how scientists and resource managers can integrate these tools into study plans or adapt restoration decisions based on recovery trajectories or changes in ocean conditions.

Marine pelagic ecosystems: the West Antarctic Peninsula

PubMed Central

Ducklow, Hugh W; Baker, Karen; Martinson, Douglas G; Quetin, Langdon B; Ross, Robin M; Smith, Raymond C; Stammerjohn, Sharon E; Vernet, Maria; Fraser, William

2006-01-01

The marine ecosystem of the West Antarctic Peninsula (WAP) extends from the Bellingshausen Sea to the northern tip of the peninsula and from the mostly glaciated coast across the continental shelf to the shelf break in the west. The glacially sculpted coastline along the peninsula is highly convoluted and characterized by deep embayments that are often interconnected by channels that facilitate transport of heat and nutrients into the shelf domain. The ecosystem is divided into three subregions, the continental slope, shelf and coastal regions, each with unique ocean dynamics, water mass and biological distributions. The WAP shelf lies within the Antarctic Sea Ice Zone (SIZ) and like other SIZs, the WAP system is very productive, supporting large stocks of marine mammals, birds and the Antarctic krill, Euphausia superba. Ecosystem dynamics is dominated by the seasonal and interannual variation in sea ice extent and retreat. The Antarctic Peninsula is one among the most rapidly warming regions on Earth, having experienced a 2°C increase in the annual mean temperature and a 6°C rise in the mean winter temperature since 1950. Delivery of heat from the Antarctic Circumpolar Current has increased significantly in the past decade, sufficient to drive to a 0.6°C warming of the upper 300 m of shelf water. In the past 50 years and continuing in the twenty-first century, the warm, moist maritime climate of the northern WAP has been migrating south, displacing the once dominant cold, dry continental Antarctic climate and causing multi-level responses in the marine ecosystem. Ecosystem responses to the regional warming include increased heat transport, decreased sea ice extent and duration, local declines in ice-dependent Adélie penguins, increase in ice-tolerant gentoo and chinstrap penguins, alterations in phytoplankton and zooplankton community composition and changes in krill recruitment, abundance and availability to predators. The climate/ecological gradients extending along the WAP and the presence of monitoring systems, field stations and long-term research programmes make the region an invaluable observatory of climate change and marine ecosystem response. PMID:17405208

Establishing research strategies, methodologies and technologies to link genomics and proteomics to seagrass productivity, community metabolism, and ecosystem carbon fluxes.

PubMed

Mazzuca, Silvia; Björk, M; Beer, S; Felisberto, P; Gobert, S; Procaccini, G; Runcie, J; Silva, J; Borges, A V; Brunet, C; Buapet, P; Champenois, W; Costa, M M; D'Esposito, D; Gullström, M; Lejeune, P; Lepoint, G; Olivé, I; Rasmusson, L M; Richir, J; Ruocco, M; Serra, I A; Spadafora, A; Santos, Rui

2013-01-01

A complete understanding of the mechanistic basis of marine ecosystem functioning is only possible through integrative and interdisciplinary research. This enables the prediction of change and possibly the mitigation of the consequences of anthropogenic impacts. One major aim of the European Cooperation in Science and Technology (COST) Action ES0609 "Seagrasses productivity. From genes to ecosystem management," is the calibration and synthesis of various methods and the development of innovative techniques and protocols for studying seagrass ecosystems. During 10 days, 20 researchers representing a range of disciplines (molecular biology, physiology, botany, ecology, oceanography, and underwater acoustics) gathered at The Station de Recherches Sous-marines et Océanographiques (STARESO, Corsica) to study together the nearby Posidonia oceanica meadow. STARESO is located in an oligotrophic area classified as "pristine site" where environmental disturbances caused by anthropogenic pressure are exceptionally low. The healthy P. oceanica meadow, which grows in front of the research station, colonizes the sea bottom from the surface to 37 m depth. During the study, genomic and proteomic approaches were integrated with ecophysiological and physical approaches with the aim of understanding changes in seagrass productivity and metabolism at different depths and along daily cycles. In this paper we report details on the approaches utilized and we forecast the potential of the data that will come from this synergistic approach not only for P. oceanica but for seagrasses in general.

Establishing Research Strategies, Methodologies and Technologies to Link Genomics and Proteomics to Seagrass Productivity, Community Metabolism, and Ecosystem Carbon Fluxes

PubMed Central

Mazzuca, Silvia; Björk, M.; Beer, S.; Felisberto, P.; Gobert, S.; Procaccini, G.; Runcie, J.; Silva, J.; Borges, A. V.; Brunet, C.; Buapet, P.; Champenois, W.; Costa, M. M.; D’Esposito, D.; Gullström, M.; Lejeune, P.; Lepoint, G.; Olivé, I.; Rasmusson, L. M.; Richir, J.; Ruocco, M.; Serra, I. A.; Spadafora, A.; Santos, Rui

2013-01-01

A complete understanding of the mechanistic basis of marine ecosystem functioning is only possible through integrative and interdisciplinary research. This enables the prediction of change and possibly the mitigation of the consequences of anthropogenic impacts. One major aim of the European Cooperation in Science and Technology (COST) Action ES0609 “Seagrasses productivity. From genes to ecosystem management,” is the calibration and synthesis of various methods and the development of innovative techniques and protocols for studying seagrass ecosystems. During 10 days, 20 researchers representing a range of disciplines (molecular biology, physiology, botany, ecology, oceanography, and underwater acoustics) gathered at The Station de Recherches Sous-marines et Océanographiques (STARESO, Corsica) to study together the nearby Posidonia oceanica meadow. STARESO is located in an oligotrophic area classified as “pristine site” where environmental disturbances caused by anthropogenic pressure are exceptionally low. The healthy P. oceanica meadow, which grows in front of the research station, colonizes the sea bottom from the surface to 37 m depth. During the study, genomic and proteomic approaches were integrated with ecophysiological and physical approaches with the aim of understanding changes in seagrass productivity and metabolism at different depths and along daily cycles. In this paper we report details on the approaches utilized and we forecast the potential of the data that will come from this synergistic approach not only for P. oceanica but for seagrasses in general. PMID:23515425

The origins of tropical marine biodiversity.

PubMed

Bowen, Brian W; Rocha, Luiz A; Toonen, Robert J; Karl, Stephen A

2013-06-01

Recent phylogeographic studies have overturned three paradigms for the origins of marine biodiversity. (i) Physical (allopatric) isolation is not the sole avenue for marine speciation: many species diverge along ecological boundaries. (ii) Peripheral habitats such as oceanic archipelagos are not evolutionary graveyards: these regions can export biodiversity. (iii) Speciation in marine and terrestrial ecosystems follow similar processes but are not the same: opportunities for allopatric isolation are fewer in the oceans, leaving greater opportunity for speciation along ecological boundaries. Biodiversity hotspots such as the Caribbean Sea and the Indo-Pacific Coral Triangle produce and export species, but can also accumulate biodiversity produced in peripheral habitats. Both hotspots and peripheral ecosystems benefit from this exchange in a process dubbed biodiversity feedback. Copyright © 2013 Elsevier Ltd. All rights reserved.

A practical guide to the application of the IUCN Red List of Ecosystems criteria.

PubMed

Rodríguez, Jon Paul; Keith, David A; Rodríguez-Clark, Kathryn M; Murray, Nicholas J; Nicholson, Emily; Regan, Tracey J; Miller, Rebecca M; Barrow, Edmund G; Bland, Lucie M; Boe, Kaia; Brooks, Thomas M; Oliveira-Miranda, María A; Spalding, Mark; Wit, Piet

2015-02-19

The newly developed IUCN Red List of Ecosystems is part of a growing toolbox for assessing risks to biodiversity, which addresses ecosystems and their functioning. The Red List of Ecosystems standard allows systematic assessment of all freshwater, marine, terrestrial and subterranean ecosystem types in terms of their global risk of collapse. In addition, the Red List of Ecosystems categories and criteria provide a technical base for assessments of ecosystem status at the regional, national, or subnational level. While the Red List of Ecosystems criteria were designed to be widely applicable by scientists and practitioners, guidelines are needed to ensure they are implemented in a standardized manner to reduce epistemic uncertainties and allow robust comparisons among ecosystems and over time. We review the intended application of the Red List of Ecosystems assessment process, summarize 'best-practice' methods for ecosystem assessments and outline approaches to ensure operational rigour of assessments. The Red List of Ecosystems will inform priority setting for ecosystem types worldwide, and strengthen capacity to report on progress towards the Aichi Targets of the Convention on Biological Diversity. When integrated with other IUCN knowledge products, such as the World Database of Protected Areas/Protected Planet, Key Biodiversity Areas and the IUCN Red List of Threatened Species, the Red List of Ecosystems will contribute to providing the most complete global measure of the status of biodiversity yet achieved. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

Climate variability and marine ecosystem impacts: a North Atlantic perspective

NASA Astrophysics Data System (ADS)

Parsons, L. S.; Lear, W. H.

In recent decades it has been recognized that in the North Atlantic climatic variability has been largely driven by atmospheric forcing related to the North Atlantic Oscillation (NAO). The NAO index began a pronounced decline around 1950 to a low in the 1960s. From 1970 onward the NAO index increased to its most extreme and persistent positive phase during the late 1980s and early 1990s. Changes in the pattern of the NAO have differential impacts on the opposite sides of the North Atlantic and differential impacts in the north and south. The changes in climate resulting from changes in the NAO appear to have had substantial impacts on marine ecosystems, in particular, on fish productivity, with the effects varying from region to region. An examination of several species and stocks, e.g. gadoids, herring and plankton in the Northeast Atlantic and cod and shellfish in the Northwest Atlantic, indicates that there is a link between long-term trends in the NAO and the productivity of various components of the marine ecosystem. While broad trends are evident, the mechanisms are poorly understood. Further research is needed to improve our understanding of how this climate variability affects the productivity of various components of the North Atlantic marine ecosystem.

Microbial mediated retention/transformation of organic and inorganic materials in freshwater and marine ecosystems

EPA Science Inventory

Aquatic ecosystems are globally connected by hydrological and biogeochemical cycles. Microorganisms inhabiting aquatic ecosystems form the basis of food webs, mediate essential element cycles, decompose natural organic matter, transform inorganic nutrients and metals, and degrad...

Assessment of coastal management options by means of multilayered ecosystem models

NASA Astrophysics Data System (ADS)

Nobre, Ana M.; Ferreira, João G.; Nunes, João P.; Yan, Xiaojun; Bricker, Suzanne; Corner, Richard; Groom, Steve; Gu, Haifeng; Hawkins, Anthony J. S.; Hutson, Rory; Lan, Dongzhao; Silva, João D. Lencart e.; Pascoe, Philip; Telfer, Trevor; Zhang, Xuelei; Zhu, Mingyuan

2010-03-01

This paper presents a multilayered ecosystem modelling approach that combines the simulation of the biogeochemistry of a coastal ecosystem with the simulation of the main forcing functions, such as catchment loading and aquaculture activities. This approach was developed as a tool for sustainable management of coastal ecosystems. A key feature is to simulate management scenarios that account for changes in multiple uses and enable assessment of cumulative impacts of coastal activities. The model was applied to a coastal zone in China with large aquaculture production and multiple catchment uses, and where management efforts to improve water quality are under way. Development scenarios designed in conjunction with local managers and aquaculture producers include the reduction of fish cages and treatment of wastewater. Despite the reduction in nutrient loading simulated in three different scenarios, inorganic nutrient concentrations in the bay were predicted to exceed the thresholds for poor quality defined by Chinese seawater quality legislation. For all scenarios there is still a Moderate High to High nutrient loading from the catchment, so further reductions might be enacted, together with additional decreases in fish cage culture. The model predicts that overall, shellfish production decreases by 10%-28% using any of these development scenarios, principally because shellfish growth is being sustained by the substances to be reduced for improvement of water quality. The model outcomes indicate that this may be counteracted by zoning of shellfish aquaculture at the ecosystem level in order to optimize trade-offs between productivity and environmental effects. The present case study exemplifies the value of multilayered ecosystem modelling as a tool for Integrated Coastal Zone Management and for the adoption of ecosystem approaches for marine resource management. This modelling approach can be applied worldwide, and may be particularly useful for the application of coastal management regulation, for instance in the implementation of the European Marine Strategy Framework Directive.

Pteropods on the edge: Cumulative effects of ocean acidification, warming, and deoxygenation

NASA Astrophysics Data System (ADS)

Bednaršek, Nina; Harvey, Chris J.; Kaplan, Isaac C.; Feely, Richard A.; Možina, Jasna

2016-06-01

We review the state of knowledge of the individual and community responses of euthecosome (shelled) pteropods in the context of global environmental change. In particular, we focus on their responses to ocean acidification, in combination with ocean warming and ocean deoxygenation, as inferred from a growing body of empirical literature, and their relatively nascent place in ecosystem-scale models. Our objectives are: (1) to summarize the threats that these stressors pose to pteropod populations; (2) to demonstrate that pteropods are strong candidate indicators for cumulative effects of OA, warming, and deoxygenation in marine ecosystems; and (3) to provide insight on incorporating pteropods into population and ecosystem models, which will help inform ecosystem-based management of marine resources under future environmental regimes.

Mycosporine-like amino acids are multifunctional molecules in sea hares and their marine community

PubMed Central

Kicklighter, Cynthia E.; Kamio, Michiya; Nguyen, Linh; Germann, Markus W.; Derby, Charles D.

2011-01-01

Molecules of keystone significance are relatively rare, yet mediate a variety of interactions between organisms. They influence the distribution and abundance of species, the transfer of energy across multiple trophic levels, and thus they play significant roles in structuring ecosystems. Despite their potential importance in facilitating our understanding of ecological systems, only three molecules thus far have been proposed as molecules of keystone significance: saxitoxin and dimethyl sulfide in marine communities and tetrodotoxin in riparian communities. In the course of studying the neuroecology of chemical defenses, we identified three mycosporine-like amino acids (MAAs)—N-ethanol palythine (= asterina-330), N-isopropanol palythine (= aplysiapalythine A), and N-ethyl palythine (= aplysiapalythine B)—as intraspecific alarm cues for sea hares (Aplysia californica). These alarm cues are released in the ink secretion of sea hares and cause avoidance behaviors in neighboring conspecifics. Further, we show that these three bioactive MAAs, two [aplysiapalythine A (APA) and -B (APB)] being previously unknown molecules, are present in the algal diet of sea hares and are concentrated in their defensive secretion as well as in their skin. MAAs are known to be produced by algae, fungi, and cyanobacteria and are acquired by many aquatic animals through trophic interactions. MAAs are widely used as sunscreens, among other uses, but sea hares modify their function to serve a previously undocumented role, as intraspecific chemical cues. Our findings highlight the multifunctionality of MAAs and their role in ecological connectivity, suggesting that they may function as molecules of keystone significance in marine ecosystems. PMID:21709250

Marine Planning for Potential Wave Energy Facility Placement Amongst a Crowded Sea of Existing Resource Uses

NASA Astrophysics Data System (ADS)

Feist, B. E.; Fuller, E.; Plummer, M. L.

2016-12-01

Conversion to renewable energy sources is a logical response to increasing pressure to reduce greenhouse gas emissions. Ocean wave energy is the least developed renewable energy source, despite having the highest energy per unit area. While many hurdles remain in developing wave energy, assessing potential conflicts and evaluating tradeoffs with existing uses is essential. Marine planning encompasses a broad array of activities that take place in and affect large marine ecosystems, making it an ideal tool for evaluating wave energy resource use conflicts. In this study, we focus on the potential conflicts between wave energy conversion (WEC) facilities and existing marine uses in the context of marine planning, within the California Current Large Marine Ecosystem. First, we evaluated wave energy facility development using the Wave Energy Model (WEM) of the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) toolkit. Second, we ran spatial analyses on model output to identify conflicts with existing marine uses including AIS based vessel traffic, VMS and observer based measures of commercial fishing effort, and marine conservation areas. We found that regions with the highest wave energy potential were distant from major cities and that infrastructure limitations (cable landing sites) restrict integration with existing power grids. We identified multiple spatial conflicts with existing marine uses; especially shipping vessels and various commercial fishing fleets, and overlap with marine conservation areas varied by conservation designation. While wave energy generation facilities may be economically viable in the California Current, this viability must be considered within the context of the costs associated with conflicts that arise with existing marine uses. Our analyses can be used to better inform placement of WEC devices (as well as other types of renewable energy facilities) in the context of marine planning by accounting for economic tradeoffs and providing spatially explicit site prioritization.

Distribution and abundance of phytobenthic communities: Implications for connectivity and ecosystem functioning in a Black Sea Marine Protected Area

NASA Astrophysics Data System (ADS)

Berov, Dimitar; Todorova, Valentina; Dimitrov, Lubomir; Rinde, Eli; Karamfilov, Ventzislav

2018-01-01

The distribution and abundance of macroalgal communities in a Marine Protected Area (MPA) along the Bulgarian Black Sea coast were mapped and quantified, with particular focus on the previously unstudied P. crispa lower-infralittoral communities on Ostrea edulis biogenic reefs. Data from high resolution geophysical substrate mapping were combined with benthic community observations from georeferenced benthic photographic surveys and sampling. Multivariate analysis identified four distinct assemblages of lower-infralittoral macroalgal communities at depths between 10 and 17 m, dominated by Phyllophora crispa, Apoglossum ruscifoluim, Zanardinia typus and Gelidium spp. Maxent software analysis showed distinct preferences of the identified communities to areas with specific ranges of depth, inclination and curvature, with P. crispa more frequently occurring on vertical oyster biogenic reef structures. By combining production rates from literature, biomass measurements and the produced habitat maps, the highest proportion of primary production and DOC release was shown for the upper infralittoral Cystoseira barbata and Cystoseira bosphorica, followed by the production of the lower-infralittoral macroalgae. The observed distribution of P. crispa within the studied MPA was related to the network of Natura 2000 maritime MPAs along the Bulgarian Black Sea coast, which indicated that the connectivity of the populations of the species within the established network is insufficient within this cell of ecosystem functioning.

Do postlarval amphidromous fishes transport marine‐derived nutrients and pollutants to Caribbean streams?

USGS Publications Warehouse

Engman, Augustin C.; Kwak, Thomas J.; Cope, W. Gregory

2018-01-01

Diadromous fishes are known biotransport vectors that can move nutrients, energy and contaminants in an upstream direction in lotic ecosystems. This function has been demonstrated repeatedly in anadromous salmonids, but the role of other diadromous species, especially tropical taxa, as biotransport vectors is less studied. Amphidromous fish species exhibit potential to act as upstream vectors of nutrients and contaminants in their postlarval and juvenile stages, but this role is largely unknown because of limited understanding of larval growth habitats. Moreover, because some species are harvested in artisanal fisheries as postlarvae, and postlarvae are consumed by riverine and estuarine predators, heavy contaminant loads may present a human or wildlife health concern. This research incorporates stable isotope and contaminant analyses to infer larval habitats and contaminant accumulation of amphidromous fishes on the Caribbean island of Puerto Rico. The isotopic signatures of postlarval amphidromous fishes indicated marine basal sources and food web components, rather than those from riverine habitats. Additionally, postlarvae did not contain concentrations of anthropogenic pollutants that would be of ecological or human health concern. These findings are the first and strongest evidence that amphidromous fish postlarvae function as biotransport vectors of marine nutrients into and up river ecosystems without posing a health threat to the receiving food web or human consumers.

Global patterns and predictors of fish species richness in estuaries.

PubMed

Vasconcelos, Rita P; Henriques, Sofia; França, Susana; Pasquaud, Stéphanie; Cardoso, Inês; Laborde, Marina; Cabral, Henrique N

2015-09-01

1. Knowledge of global patterns of biodiversity and regulating variables is indispensable to develop predictive models. 2. The present study used predictive modelling approaches to investigate hypotheses that explain the variation in fish species richness between estuaries over a worldwide spatial extent. Ultimately, such models will allow assessment of future changes in ecosystem structure and function as a result of environmental changes. 3. A comprehensive worldwide data base was compiled of the fish assemblage composition and environmental characteristics of estuaries. Generalized Linear Models were used to quantify how variation in species richness among estuaries is related to historical events, energy dynamics and ecosystem characteristics, while controlling for sampling effects. 4. At the global extent, species richness differed among marine biogeographic realms and continents and increased with mean sea surface temperature, terrestrial net primary productivity and the stability of connectivity with a marine ecosystem (open vs. temporarily open estuaries). At a smaller extent (within a marine biogeographic realm or continent), other characteristics were also important in predicting variation in species richness, with species richness increasing with estuary area and continental shelf width. 5. The results suggest that species richness in an estuary is defined by predictors that are spatially hierarchical. Over the largest spatial extents, species richness is influenced by the broader distributions and habitat use patterns of marine and freshwater species that can colonize estuaries, which are in turn governed by history contingency, energy dynamics and productivity variables. Species richness is also influenced by more regional and local parameters that can further affect the process of community colonization in an estuary including the connectivity of the estuary with the adjacent marine habitat, and, over smaller spatial extents, the size of these habitats. In summary, patterns of species richness in estuaries across large spatial extents seem to reflect from global to local processes acting on community colonization. The importance of considering spatial extent, sampling effects and of combining history and contemporary environmental characteristics when exploring biodiversity is highlighted. © 2015 The Authors. Journal of Animal Ecology published by John Wiley & Sons on behalf of the British Ecological Society.

Displacement effects of heavy human use on coral reef predators within the Molokini Marine Life Conservation District.

PubMed

Filous, Alexander; Friedlander, Alan M; Koike, Haruko; Lammers, Marc; Wong, Adam; Stone, Kristy; Sparks, Russell T

2017-08-15

The impact of marine ecotourism on reef predators is poorly understood and there is growing concern that overcrowding in Marine Protected Areas (MPAs) may disturb the species that these areas were established to protect. To improve our understanding of this issue, we used acoustic telemetry to examine the relationship between human activity at the Molokini Marine Life Conservation District (MLCD) and the habitat use of five reef-associated predators (Caranx melampygus, Caranx ignobilis, Triaenodon obesus, Carcharhinus amblyrhynchos, and Aprion virscens). During peak hours of human use, there was a negative relationship (R 2 =0.77, P<0.001) between the presence of bluefin trevally (Caranx melampygus) and vessels in subzone A. No other species showed strong evidence of this relationship. However, our results suggest that during this time, the natural ecosystem function that the reserve was established to protect may be compromised and overcrowding should be considered when managing MPAs. Copyright © 2017 Elsevier Ltd. All rights reserved.

The effect of bio-irrigation by the polychaete Lanice conchilega on active denitrifiers: Distribution, diversity and composition of nosZ gene

PubMed Central

Yazdani Foshtomi, Maryam; Leliaert, Frederik; Derycke, Sofie; Willems, Anne; Vincx, Magda

2018-01-01

The presence of large densities of the piston-pumping polychaete Lanice conchilega can have important consequences for the functioning of marine sediments. It is considered both an allogenic and an autogenic ecosystem engineer, affecting spatial and temporal biogeochemical gradients (oxygen concentrations, oxygen penetration depth and nutrient concentrations) and physical properties (grain size) of marine sediments, which could affect functional properties of sediment-inhabiting microbial communities. Here we investigated whether density-dependent effects of L. conchilega affected horizontal (m-scale) and vertical (cm-scale) patterns in the distribution, diversity and composition of the typical nosZ gene in the active denitrifying organisms. This gene plays a major role in N2O reduction in coastal ecosystems as the last step completing the denitrification pathway. We showed that both vertical and horizontal composition and richness of nosZ gene were indeed significantly affected when large densities of the bio-irrigator were present. This could be directly related to allogenic ecosystem engineering effects on the environment, reflected in increased oxygen penetration depth and oxygen concentrations in the upper cm of the sediment in high densities of L. conchilega. A higher diversity (Shannon diversity and inverse Simpson) of nosZ observed in patches with high L. conchilega densities (3,185–3,440 ind. m-2) at deeper sediment layers could suggest a downward transport of NO3− to deeper layers resulting from bio-irrigation as well. Hence, our results show the effect of L. conchilega bio-irrigation activity on denitrifying organisms in L. conchilega reefs. PMID:29408934

Distribution, structure and function of Nordic eelgrass (Zostera marina) ecosystems: implications for coastal management and conservation.

PubMed

Boström, Christoffer; Baden, Susanne; Bockelmann, Anna-Christina; Dromph, Karsten; Fredriksen, Stein; Gustafsson, Camilla; Krause-Jensen, Dorte; Möller, Tiia; Nielsen, Søren Laurentius; Olesen, Birgit; Olsen, Jeanine; Pihl, Leif; Rinde, Eli

2014-06-01

This paper focuses on the marine foundation eelgrass species, Zostera marina , along a gradient from the northern Baltic Sea to the north-east Atlantic. This vast region supports a minimum of 1480 km 2 eelgrass (maximum >2100 km 2 ), which corresponds to more than four times the previously quantified area of eelgrass in Western Europe.Eelgrass meadows in the low salinity Baltic Sea support the highest diversity (4-6 spp.) of angiosperms overall, but eelgrass productivity is low (<2 g dw m -2 d -1 ) and meadows are isolated and genetically impoverished. Higher salinity areas support monospecific meadows, with higher productivity (3-10 g dw m -2 d -1 ) and greater genetic connectivity. The salinity gradient further imposes functional differences in biodiversity and food webs, in particular a decline in number, but increase in biomass of mesograzers in the Baltic.Significant declines in eelgrass depth limits and areal cover are documented, particularly in regions experiencing high human pressure. The failure of eelgrass to re-establish itself in affected areas, despite nutrient reductions and improved water quality, signals complex recovery trajectories and calls for much greater conservation effort to protect existing meadows.The knowledge base for Nordic eelgrass meadows is broad and sufficient to establish monitoring objectives across nine national borders. Nevertheless, ensuring awareness of their vulnerability remains challenging. Given the areal extent of Nordic eelgrass systems and the ecosystem services they provide, it is crucial to further develop incentives for protecting them. © 2014 The Authors. Aquatic Conservation: Marine and Freshwater Ecosystems published by John Wiley & Sons, Ltd.

Toxicity of TiO2, in nanoparticle or bulk form to freshwater and marine microalgae under visible light and UV-A radiation.

PubMed

Sendra, M; Moreno-Garrido, I; Yeste, M P; Gatica, J M; Blasco, J

2017-08-01

Use of titanium dioxide nanoparticles (TiO 2 NPs) has become a part of our daily life and the high environmental concentrations predicted to accumulate in aquatic ecosystems are cause for concern. Although TiO 2 has only limited reactivity, at the nanoscale level its physico-chemical properties and toxicity are different compared with bulk material. Phytoplankton is a key trophic level in fresh and marine ecosystems, and the toxicity provoked by these nanoparticles can affect the structure and functioning of ecosystems. Two microalgae species, one freshwater (Chlamydomonas reinhardtii) and the other marine (Phaeodactylum tricornutum), have been selected for testing the toxicity of TiO 2 in NP and conventional bulk form and, given its photo-catalytic properties, the effect of UV-A was also checked. Growth inhibition, quantum yield reduction, increase of intracellular ROS production, membrane cell damage and production of exo-polymeric substances (EPS) were selected as variables to measure. TiO 2 NPs and bulk TiO 2 show a relationship between the size of agglomerates and time in freshwater and saltwater, but not in ultrapure water. Under two treatments, UV-A (6 h per day) and no UV-A exposure, NPs triggered stronger cytotoxic responses than bulk material. TiO 2 NPs were also associated with greater production of reactive oxygen species and damage to membrane. However, microalgae exposed to TiO 2 NPs and bulk TiO 2 under UV-A were found to be more sensitive than in the visible light condition. The marine species (P. tricornutum) was more sensitive than the freshwater species, and higher Ti internalization was measured. Exopolymeric substances (EPS) were released from microalgae in the culture media, in the presence of TiO 2 in both forms. This may be a possible defense mechanism by these cells, which would enhance processes of homoagglomeration and settling, and thus reduce bioavailability. Copyright © 2017 Elsevier Ltd. All rights reserved.

Delineating ecological regions in marine systems: Integrating physical structure and community composition to inform spatial management in the eastern Bering Sea

NASA Astrophysics Data System (ADS)

Baker, Matthew R.; Hollowed, Anne B.

2014-11-01

Characterizing spatial structure and delineating meaningful spatial boundaries have useful applications to understanding regional dynamics in marine systems, and are integral to ecosystem approaches to fisheries management. Physical structure and drivers combine with biological responses and interactions to organize marine systems in unique ways at multiple scales. We apply multivariate statistical methods to define spatially coherent ecological units or ecoregions in the eastern Bering Sea. We also illustrate a practical approach to integrate data on species distribution, habitat structure and physical forcing mechanisms to distinguish areas with distinct biogeography as one means to define management units in large marine ecosystems. We use random forests to quantify the relative importance of habitat and environmental variables to the distribution of individual species, and to quantify shifts in multispecies assemblages or community composition along environmental gradients. Threshold shifts in community composition are used to identify regions with distinct physical and biological attributes, and to evaluate the relative importance of predictor variables to determining regional boundaries. Depth, bottom temperature and frontal boundaries were dominant factors delineating distinct biological communities in this system, with a latitudinal divide at approximately 60°N. Our results indicate that distinct climatic periods will shift habitat gradients and that dynamic physical variables such as temperature and stratification are important to understanding temporal stability of ecoregion boundaries. We note distinct distribution patterns among functional guilds and also evidence for resource partitioning among individual species within each guild. By integrating physical and biological data to determine spatial patterns in community composition, we partition ecosystems along ecologically significant gradients. This may provide a basis for defining spatial management units or serve as a baseline index for analyses of structural shifts in the physical environment, species abundance and distribution, and community dynamics over time.

Oceanographic gradients and seabird prey community dynamics in glacial fjords

USGS Publications Warehouse

Arimitsu, Mayumi L.; Piatt, John F.; Madison, Erica N.; Conaway, Jeffrey S.; Hillgruber, N.

2012-01-01

Glacial fjord habitats are undergoing rapid change as a result of contemporary global warming, yet little is known about how glaciers influence marine ecosystems. These ecosystems provide important feeding, breeding and rearing grounds for a wide variety of marine organisms, including seabirds of management concern. To characterize ocean conditions and marine food webs near tidewater glaciers, we conducted monthly surveys of oceanographic variables, plankton, fish and seabirds in Kenai Fjords, Alaska, from June to August of 2007 and 2008. We also measured tidal current velocities near glacial features. We found high sediment load from glacial river runoff played a major role in structuring the fjord marine ecosystem. Submerged moraines (sills) isolated cool, fresh, stratified and silt-laden inner fjord habitats from oceanic influence. Near tidewater glaciers, surface layers of turbid glacial runoff limited availability of light to phytoplankton, but macrozooplankton were abundant in surface waters, perhaps due to the absence of a photic cue for diel migration. Fish and zooplankton community structure varied along an increasing temperature gradient throughout the summer. Acoustic measurements indicated that low density patches of fish and zooplankton were available in the surface waters near glacial river outflows. This is the foraging habitat occupied most by Kittlitz's murrelet (Brachyramphus brevirostris), a rare seabird that appears to be specialized for life in glacially influenced environments. Kittlitz's murrelets were associated with floating glacial ice, and they were more likely to occur near glaciers, in deeper water, and in areas with high acoustic backscatter. Kittlitz's murrelet at-sea distribution was limited to areas influenced by turbid glacial outflows, and where prey was concentrated near the surface in waters with low light penetration. Tidewater glaciers impart unique hydrographic characteristics that influence marine plankton and fish communities, and this has cascading effects on marine food webs in these ecosystems.

A birds-eye view of biological connectivity in mangrove systems

NASA Astrophysics Data System (ADS)

Buelow, Christina; Sheaves, Marcus

2015-01-01

Considerable advances in understanding of biological connectivity have flowed from studies of fish-facilitated connectivity within the coastal ecosystem mosaic. However, there are limits to the information that fish can provide on connectivity. Mangrove-bird communities have the potential to connect coastal habitats in different ways and at different scales than fish, so incorporation of these links into our models of coastal ecosystem mosaics affords the opportunity to greatly increase the breadth of our understanding. We review the habitat and foraging requirements of mangrove-bird functional groups to understand how bird use of mangroves facilitates biological connectivity in coastal ecosystem mosaics, and how that connectivity adds to the diversity and complexity of ecological processes in mangrove ecosystems. Avian biological connectivity is primarily characterized by foraging behavior and habitat/resource requirements. Therefore, the consequence of bird links for coastal ecosystem functioning largely depends on patterns of habitat use and foraging, and potentially influences nutrient cycling, top-down control and genetic information linkage. Habitats that experience concentrated bird guano deposition have high levels of nitrogen and phosphorus, placing particular importance on the consequences of avian nutrient translocation and subsidization for coastal ecosystem functioning. High mobility allows mangrove-bird communities to link mangrove forests to other mangrove, terrestrial and marine-pelagic systems. Therefore, the spatial scale of coastal connectivity facilitated by birds is substantially more extensive than fish-facilitated connectivity. In particular, migratory birds link habitats at regional, continental and inter-continental scales as they travel among seasonally available feeding areas from breeding grounds to non-breeding grounds; scales at which there are few fish equivalents. Knowledge of the nature and patterns of fish connectivity have contributed to shifting the initial, historical perception of mangrove-ecosystem functioning from that of a simple system based on nutrient and energy retention, to a view that includes fish-facilitated energy export. In a similar way, understanding the nature and implications of mangrove connectivity through bird movements and migrations affords new possibilities for revising our view of the extent of functional links between mangroves and other ecosystems.

Implementation of marine spatial planning in shellfish aquaculture management: modeling studies in a Norwegian fjord.

PubMed

Filgueira, Ramon; Grant, Jon; Strand, Øivind

2014-06-01

Shellfish carrying capacity is determined by the interaction of a cultured species with its ecosystem, which is strongly influenced by hydrodynamics. Water circulation controls the exchange of matter between farms and the adjacent areas, which in turn establishes the nutrient supply that supports phytoplankton populations. The complexity of water circulation makes necessary the use of hydrodynamic models with detailed spatial resolution in carrying capacity estimations. This detailed spatial resolution also allows for the study of processes that depend on specific spatial arrangements, e.g., the most suitable location to place farms, which is crucial for marine spatial planning, and consequently for decision support systems. In the present study, a fully spatial physical-biogeochemical model has been combined with scenario building and optimization techniques as a proof of concept of the use of ecosystem modeling as an objective tool to inform marine spatial planning. The object of this exercise was to generate objective knowledge based on an ecosystem approach to establish new mussel aquaculture areas in a Norwegian fjord. Scenario building was used to determine the best location of a pump that can be used to bring nutrient-rich deep waters to the euphotic layer, increasing primary production, and consequently, carrying capacity for mussel cultivation. In addition, an optimization tool, parameter estimation (PEST), was applied to the optimal location and mussel standing stock biomass that maximize production, according to a preestablished carrying capacity criterion. Optimization tools allow us to make rational and transparent decisions to solve a well-defined question, decisions that are essential for policy makers. The outcomes of combining ecosystem models with scenario building and optimization facilitate planning based on an ecosystem approach, highlighting the capabilities of ecosystem modeling as a tool for marine spatial planning.

Climate change alters stability and species potential interactions in a large marine ecosystem.

PubMed

Griffith, Gary P; Strutton, Peter G; Semmens, Jayson M

2018-01-01

We have little empirical evidence of how large-scale overlaps between large numbers of marine species may have altered in response to human impacts. Here, we synthesized all available distribution data (>1 million records) since 1992 for 61 species of the East Australian marine ecosystem, a global hot spot of ocean warming and continuing fisheries exploitation. Using a novel approach, we constructed networks of the annual changes in geographical overlaps between species. Using indices of changes in species overlap, we quantified changes in the ecosystem stability, species robustness, species sensitivity and structural keystone species. We then compared the species overlap indices with environmental and fisheries data to identify potential factors leading to the changes in distributional overlaps between species. We found that the structure of the ecosystem has changed with a decrease in asymmetrical geographical overlaps between species. This suggests that the ecosystem has become less stable and potentially more susceptible to environmental perturbations. Most species have shown a decrease in overlaps with other species. The greatest decrease in species overlap robustness and sensitivity to the loss of other species has occurred in the pelagic community. Some demersal species have become more robust and less sensitive. Pelagic structural keystone species, predominately the tunas and billfish, have been replaced by demersal fish species. The changes in species overlap were strongly correlated with regional oceanographic changes, in particular increasing ocean warming and the southward transport of warmer and saltier water with the East Australian Current, but less correlated with fisheries catch. Our study illustrates how large-scale multispecies distribution changes can help identify structural changes in marine ecosystems associated with climate change. © 2017 John Wiley & Sons Ltd.

Noise in the Sea and Its Impacts on Marine Organisms

PubMed Central

Peng, Chao; Zhao, Xinguo; Liu, Guangxu

2015-01-01

With the growing utilization and exploration of the ocean, anthropogenic noise increases significantly and gives rise to a new kind of pollution: noise pollution. In this review, the source and the characteristics of noise in the sea, the significance of sound to marine organisms, and the impacts of noise on marine organisms are summarized. In general, the studies about the impact of noise on marine organisms are mainly on adult fish and mammals, which account for more than 50% and 20% of all the cases reported. Studies showed that anthropogenic noise can cause auditory masking, leading to cochlear damage, changes in individual and social behavior, altered metabolisms, hampered population recruitment, and can subsequently affect the health and service functions of marine ecosystems. However, since different sampling methodologies and unstandarized measurements were used and the effects of noise on marine organisms are dependent on the characteristics of the species and noise investigated, it is difficult to compare the reported results. Moreover, the scarcity of studies carried out with other species and with larval or juvenile individuals severely constrains the present understanding of noise pollution. In addition, further studies are needed to reveal in detail the causes for the detected impacts. PMID:26437424

How to boost marine fungal research: A first step towards a multidisciplinary approach by combining molecular fungal ecology and natural products chemistry.

PubMed

Reich, Marlis; Labes, Antje

2017-12-01

Marine fungi have attracted attention in recent years due to increased appreciation of their functional role in ecosystems and as important sources of new natural products. The concomitant development of various "omic" technologies has boosted fungal research in the fields of biodiversity, physiological ecology and natural product biosynthesis. Each of these research areas has its own research agenda, scientific language and quality standards, which have so far hindered an interdisciplinary exchange. Inter- and transdisciplinary interactions are, however, vital for: (i) a detailed understanding of the ecological role of marine fungi, (ii) unlocking their hidden potential for natural product discovery, and (iii) designing access routes for biotechnological production. In this review and opinion paper, we describe the two different "worlds" of marine fungal natural product chemists and marine fungal molecular ecologists. The individual scientific approaches and tools employed are summarised and explained, and enriched with a first common glossary. We propose a strategy to find a multidisciplinary approach towards a comprehensive view on marine fungi and their chemical potential. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Noise in the Sea and Its Impacts on Marine Organisms.

PubMed

Peng, Chao; Zhao, Xinguo; Liu, Guangxu

2015-09-30

With the growing utilization and exploration of the ocean, anthropogenic noise increases significantly and gives rise to a new kind of pollution: noise pollution. In this review, the source and the characteristics of noise in the sea, the significance of sound to marine organisms, and the impacts of noise on marine organisms are summarized. In general, the studies about the impact of noise on marine organisms are mainly on adult fish and mammals, which account for more than 50% and 20% of all the cases reported. Studies showed that anthropogenic noise can cause auditory masking, leading to cochlear damage, changes in individual and social behavior, altered metabolisms, hampered population recruitment, and can subsequently affect the health and service functions of marine ecosystems. However, since different sampling methodologies and unstandarized measurements were used and the effects of noise on marine organisms are dependent on the characteristics of the species and noise investigated, it is difficult to compare the reported results. Moreover, the scarcity of studies carried out with other species and with larval or juvenile individuals severely constrains the present understanding of noise pollution. In addition, further studies are needed to reveal in detail the causes for the detected impacts.

Monitoring strategies for drill cutting discharge in the vicinity of cold-water coral ecosystems.

PubMed

Purser, Autun; Thomsen, Laurenz

2012-11-01

Cold-water coral reefs represent some of the most biodiverse and biomass rich ecosystems in the marine environment. Despite this, ecosystem functioning is still poorly understood and the susceptibility of key species to anthropogenic activities and pollutants is unknown. In European waters, cold-water corals are often found in greatest abundance on the continental margin, often in regions rich in hydrocarbon reserves. In this viewpoint paper we discuss some of the current strategies employed in predicting and minimizing exposure of cold-water coral reef ecosystems on the Norwegian margin to waste materials produced during offshore drilling operations by the oil and gas industry. In the light of recent in situ and experimental research conducted with the key reef species Lophelia pertusa, we present some possible improvements to these strategies which may be utilized by industry and managers to further reduce the likelihood of exposure. We further highlight important outstanding research questions in this field. Copyright © 2012 Elsevier Ltd. All rights reserved.

Ecology of the seagrasses of south Florida: a community profile

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zieman, J.C.

1982-09-01

A detailed description is given of the community structure and ecosystem processes of the seagrass ecosystems of south Florida. This description is based upon a compilation of information from numerous published and unpublished sources. The material covered includes distribution, systematics, physiology, and growth of the plants, as well as succession and community development. The role of seagrass ecosystems in providing both food and shelter for juveniles as well as foraging grounds for larger organisms is treated in detail. Emphasis is given to the functional role of seagrass communities in the overall coastal marine system. The final section considers the impactsmore » of human development on seagrass ecosystems and their value to both man and the natural system. Because seagrass systems are fully submerged and less visually obvious, recognition of their value as a natural resource has been slower than that of the emergent coastal communities. They must, however, be treated as a valuable natural resource and preserved from further degradation.« less

One hundred questions of importance to the conservation of global biological diversity.

PubMed

Sutherland, W J; Adams, W M; Aronson, R B; Aveling, R; Blackburn, T M; Broad, S; Ceballos, G; Côté, I M; Cowling, R M; Da Fonseca, G A B; Dinerstein, E; Ferraro, P J; Fleishman, E; Gascon, C; Hunter, M; Hutton, J; Kareiva, P; Kuria, A; Macdonald, D W; Mackinnon, K; Madgwick, F J; Mascia, M B; McNeely, J; Milner-Gulland, E J; Moon, S; Morley, C G; Nelson, S; Osborn, D; Pai, M; Parsons, E C M; Peck, L S; Possingham, H; Prior, S V; Pullin, A S; Rands, M R W; Ranganathan, J; Redford, K H; Rodriguez, J P; Seymour, F; Sobel, J; Sodhi, N S; Stott, A; Vance-Borland, K; Watkinson, A R

2009-06-01

We identified 100 scientific questions that, if answered, would have the greatest impact on conservation practice and policy. Representatives from 21 international organizations, regional sections and working groups of the Society for Conservation Biology, and 12 academics, from all continents except Antarctica, compiled 2291 questions of relevance to conservation of biological diversity worldwide. The questions were gathered from 761 individuals through workshops, email requests, and discussions. Voting by email to short-list questions, followed by a 2-day workshop, was used to derive the final list of 100 questions. Most of the final questions were derived through a process of modification and combination as the workshop progressed. The questions are divided into 12 sections: ecosystem functions and services, climate change, technological change, protected areas, ecosystem management and restoration, terrestrial ecosystems, marine ecosystems, freshwater ecosystems, species management, organizational systems and processes, societal context and change, and impacts of conservation interventions. We anticipate that these questions will help identify new directions for researchers and assist funders in directing funds. ©2009 Society for Conservation Biology.

Climate change, coral reef ecosystems, and management options for marine protected areas.

PubMed

Keller, Brian D; Gleason, Daniel F; McLeod, Elizabeth; Woodley, Christa M; Airamé, Satie; Causey, Billy D; Friedlander, Alan M; Grober-Dunsmore, Rikki; Johnson, Johanna E; Miller, Steven L; Steneck, Robert S

2009-12-01

Marine protected areas (MPAs) provide place-based management of marine ecosystems through various degrees and types of protective actions. Habitats such as coral reefs are especially susceptible to degradation resulting from climate change, as evidenced by mass bleaching events over the past two decades. Marine ecosystems are being altered by direct effects of climate change including ocean warming, ocean acidification, rising sea level, changing circulation patterns, increasing severity of storms, and changing freshwater influxes. As impacts of climate change strengthen they may exacerbate effects of existing stressors and require new or modified management approaches; MPA networks are generally accepted as an improvement over individual MPAs to address multiple threats to the marine environment. While MPA networks are considered a potentially effective management approach for conserving marine biodiversity, they should be established in conjunction with other management strategies, such as fisheries regulations and reductions of nutrients and other forms of land-based pollution. Information about interactions between climate change and more "traditional" stressors is limited. MPA managers are faced with high levels of uncertainty about likely outcomes of management actions because climate change impacts have strong interactions with existing stressors, such as land-based sources of pollution, overfishing and destructive fishing practices, invasive species, and diseases. Management options include ameliorating existing stressors, protecting potentially resilient areas, developing networks of MPAs, and integrating climate change into MPA planning, management, and evaluation.

Polybrominated diphenyl ethers in marine ecosystems of the American continents: foresight from current knowledge.

PubMed

Shaw, Susan D; Kannan, Kurunthachalam

2009-01-01

Polybrominated diphenyl ethers (PBDEs) are a class of synthetic halogenated organic compounds used in commercial and household products, such as textiles, furniture, and electronics, to increase their flame ignition resistance and to meet fire safety standards. The demonstrated persistence, bioaccumulation, and toxic potential of these compounds in animals and in humans are of increasing concern. The oceans are considered global sinks for PBDEs, as higher levels are found in marine organisms than in terrestrial biota. For the past three decades, North America has dominated the world market demand for PBDEs, consuming 95% of the penta-BDE formulation. Accordingly, the PBDE concentrations in marine biota and people from North America are the highest in the world and are increasing. Despite recent restrictions on penta- and octa-BDE commercial formulations, penta-BDE containing products will remain a reservoir for PBDE release for years to come, and the deca-BDE formulation is still in high-volume use. In this paper, we review all available data on the occurrence and trends of PBDEs in the marine ecosystems (air, water, sediments, invertebrates, fish, seabirds, and marine mammals) of North and South America. We outline here our concerns about the potential future impacts of large existing stores of banned PBDEs in consumer products, and the vast and growing reservoirs of deca-BDE as well as new and naturally occurring brominated compounds on marine ecosystems.

Sources, factors, mechanisms and possible solutions to pollutants in marine ecosystems.

PubMed

Mostofa, Khan M G; Liu, Cong-Qiang; Vione, Davide; Gao, Kunshan; Ogawa, Hiroshi

2013-11-01

Algal toxins or red-tide toxins produced during algal blooms are naturally-derived toxic emerging contaminants (ECs) that may kill organisms, including humans, through contaminated fish or seafood. Other ECs produced either naturally or anthropogenically ultimately flow into marine waters. Pharmaceuticals are also an important pollution source, mostly due to overproduction and incorrect disposal. Ship breaking and recycle industries (SBRIs) can also release various pollutants and substantially deteriorate habitats and marine biodiversity. Overfishing is significantly increasing due to the global food crisis, caused by an increasing world population. Organic matter (OM) pollution and global warming (GW) are key factors that exacerbate these challenges (e.g. algal blooms), to which acidification in marine waters should be added as well. Sources, factors, mechanisms and possible remedial measures of these challenges to marine ecosystems are discussed, including their eventual impact on all forms of life including humans. Copyright © 2013 Elsevier Ltd. All rights reserved.

Seabirds supply nitrogen to reef-building corals on remote Pacific islets.

PubMed

Lorrain, Anne; Houlbrèque, Fanny; Benzoni, Francesca; Barjon, Lucie; Tremblay-Boyer, Laura; Menkes, Christophe; Gillikin, David P; Payri, Claude; Jourdan, Hervé; Boussarie, Germain; Verheyden, Anouk; Vidal, Eric

2017-06-16

Seabirds concentrate nutrients from large marine areas on their nesting islands playing an important ecological role in nutrient transfer between marine and terrestrial ecosystems. Here we investigate the role of guano on corals reefs across scales by analyzing the stable nitrogen isotopic (δ 15 N) values of the scleractinian coral Pocillopora damicornis on fringing reefs around two Pacific remote islets with large seabird colonies. Marine stations closest to the seabird colonies had higher nitrate + nitrite concentrations compared to more distant stations. Coral and zooxanthellae δ 15 N values were also higher at these sites, suggesting that guano-derived nitrogen is assimilated into corals and contributes to their nitrogen requirements. The spatial extent of guano influence was however restricted to a local scale. Our results demonstrate that seabird-derived nutrients not only spread across the terrestrial ecosystem, but also affect components of the adjacent marine ecosystem. Further studies are now needed to assess if this nutrient input has a positive or negative effect for corals. Such studies on remote islets also open fresh perspectives to understand how nutrients affect coral reefs isolated from other anthropogenic stressors.

Marine reserves can mitigate and promote adaptation to climate change

PubMed Central

Roberts, Callum M.; O’Leary, Bethan C.; McCauley, Douglas J.; Cury, Philippe Maurice; Duarte, Carlos M.; Lubchenco, Jane; Pauly, Daniel; Sáenz-Arroyo, Andrea; Sumaila, Ussif Rashid; Wilson, Rod W.; Worm, Boris; Castilla, Juan Carlos

2017-01-01

Strong decreases in greenhouse gas emissions are required to meet the reduction trajectory resolved within the 2015 Paris Agreement. However, even these decreases will not avert serious stress and damage to life on Earth, and additional steps are needed to boost the resilience of ecosystems, safeguard their wildlife, and protect their capacity to supply vital goods and services. We discuss how well-managed marine reserves may help marine ecosystems and people adapt to five prominent impacts of climate change: acidification, sea-level rise, intensification of storms, shifts in species distribution, and decreased productivity and oxygen availability, as well as their cumulative effects. We explore the role of managed ecosystems in mitigating climate change by promoting carbon sequestration and storage and by buffering against uncertainty in management, environmental fluctuations, directional change, and extreme events. We highlight both strengths and limitations and conclude that marine reserves are a viable low-tech, cost-effective adaptation strategy that would yield multiple cobenefits from local to global scales, improving the outlook for the environment and people into the future. PMID:28584096

Marine reserves can mitigate and promote adaptation to climate change.

PubMed

Roberts, Callum M; O'Leary, Bethan C; McCauley, Douglas J; Cury, Philippe Maurice; Duarte, Carlos M; Lubchenco, Jane; Pauly, Daniel; Sáenz-Arroyo, Andrea; Sumaila, Ussif Rashid; Wilson, Rod W; Worm, Boris; Castilla, Juan Carlos

2017-06-13

Strong decreases in greenhouse gas emissions are required to meet the reduction trajectory resolved within the 2015 Paris Agreement. However, even these decreases will not avert serious stress and damage to life on Earth, and additional steps are needed to boost the resilience of ecosystems, safeguard their wildlife, and protect their capacity to supply vital goods and services. We discuss how well-managed marine reserves may help marine ecosystems and people adapt to five prominent impacts of climate change: acidification, sea-level rise, intensification of storms, shifts in species distribution, and decreased productivity and oxygen availability, as well as their cumulative effects. We explore the role of managed ecosystems in mitigating climate change by promoting carbon sequestration and storage and by buffering against uncertainty in management, environmental fluctuations, directional change, and extreme events. We highlight both strengths and limitations and conclude that marine reserves are a viable low-tech, cost-effective adaptation strategy that would yield multiple cobenefits from local to global scales, improving the outlook for the environment and people into the future.

Model Analysis of Tropospheric Aerosol Variability and Sources over the North Atlantic During NAAMES 2015-2016

NASA Technical Reports Server (NTRS)

Liu, Hongyu; Moore, Richard; Hostetler, Christopher; Ferrare, Richard; Fairlie, T. Duncan; Hu, Youngxiang; Chen, Gao; Hair, Johnathan W.; Johnson, Matthew; Gantt, Brett;

Special issue on the advances in understanding of the North Pacific subtropical front ecosystem

NASA Astrophysics Data System (ADS)

McKinnell, Skip; Seki, Michael P.; Ichii, Taro

2017-01-01

Subtropical, oligotrophic oceanic gyres are the largest marine ecosystems in the world. They provide important habitat for many higher trophic level species of fish, squid, seabirds, and marine mammals, with some taxa undergoing extensive seasonal migrations between the subtropical frontal region and summer feeding grounds in the subarctic. Knowledge of the structure, variability, and trends of these regions has developed slowly because of their immense size, remote location, and cost of sampling. The first consolidation of the general understanding of the physical nature of the subtropical North Pacific Ocean (and subarctic transition) was published 25 years ago (Roden, 1991) with important information on its relationship to biota added by the now defunct International North Pacific Fisheries Commission (INPFC, 1992; Ito et al., 1993). At that time, a research imperative had arisen from a need by governments to understand the effects of large-scale pelagic driftnet fishing on marine ecosystems (Wetherall, 1991).

Assessing the Impact of Human Activities on British Columbia’s Estuaries

PubMed Central

Robb, Carolyn K.

2014-01-01

The world’s marine and coastal ecosystems are under threat and single-sector management efforts have failed to address those threats. Scientific consensus suggests that management should evolve to focus on ecosystems and their human, ecological, and physical components. Estuaries are recognized globally as one of the world’s most productive and most threatened ecosystems and many estuarine areas in British Columbia (BC) have been lost or degraded. To help prioritize activities and areas for regional management efforts, spatial information on human activities that adversely affect BC’s estuaries was compiled. Using statistical analyses, estuaries were assigned to groups facing related threats that could benefit from similar management. The results show that estuaries in the most populated marine ecosections have the highest biological importance but also the highest impacts and the lowest levels of protection. This research is timely, as it will inform ongoing marine planning, land acquisition, and stewardship efforts in BC. PMID:24937486

GLOBEC (Global Ocean Ecosystems Dynamics: Northwest Atlantic program

NASA Technical Reports Server (NTRS)

1991-01-01

The specific objective of the meeting was to plan an experiment in the Northwestern Atlantic to study the marine ecosystem and its role, together with that of climate and physical dynamics, in determining fisheries recruitment. The underlying focus of the GLOBEC initiative is to understand the marine ecosystem as it related to marine living resources and to understand how fluctuation in these resources are driven by climate change and exploitation. In this sense the goal is a solid scientific program to provide basic information concerning major fisheries stocks and the environment that sustains them. The plan is to attempt to reach this understanding through a multidisciplinary program that brings to bear new techniques as disparate as numerical fluid dynamic models of ocean circulation, molecular biology and modern acoustic imaging. The effort will also make use of the massive historical data sets on fisheries and the state of the climate in a coordinated manner.

Parasites in marine food webs

USGS Publications Warehouse

Lafferty, Kevin D.

2013-01-01

Most species interactions probably involve parasites. This review considers the extent to which marine ecologists should consider parasites to fully understand marine communities. Parasites are influential parts of food webs in estuaries, temperate reefs, and coral reefs, but their ecological importance is seldom recognized. Though difficult to observe, parasites can have substantial biomass, and they can be just as common as free-living consumers after controlling for body mass and trophic level. Parasites have direct impacts on the energetics of their hosts and some affect host behaviors, with ecosystem-level consequences. Although they cause disease, parasites are sensitive components of ecosystems. In particular, they suffer secondary extinctions due to biodiversity loss. Some parasites can also return to a system after habitat restoration. For these reasons, parasites can make good indicators of ecosystem integrity. Fishing can indirectly increase or decrease parasite populations and the effects of climate change on parasites are likely to be equally as complex.

Interactions between marine biota and ENSO: a conceptual model analysis

NASA Astrophysics Data System (ADS)

Heinemann, M.; Timmermann, A.; Feudel, U.

2011-01-01

We develop a conceptual coupled atmosphere-ocean-ecosystem model for the tropical Pacific to investigate the interaction between marine biota and the El Niño-Southern Oscillation (ENSO). Ocean and atmosphere are represented by a two-box model for the equatorial Pacific cold tongue and the warm pool, including a simplified mixed layer scheme. Marine biota are represented by a three-component (nutrient, phytoplankton, and zooplankton) ecosystem model. The atmosphere-ocean model exhibits an oscillatory state which qualitatively captures the main physics of ENSO. During an ENSO cycle, the variation of nutrient upwelling, and, to a small extent, the variation of photosynthetically available radiation force an ecosystem oscillation. The simplified ecosystem in turn, due to the effect of phytoplankton on the absorption of shortwave radiation in the water column, leads to (1) a warming of the tropical Pacific, (2) a reduction of the ENSO amplitude, and (3) a prolongation of the ENSO period. We qualitatively investigate these bio-physical coupling mechanisms using continuation methods. It is demonstrated that bio-physical coupling may play a considerable role in modulating ENSO variability.

Overfishing and the replacement of demersal finfish by shellfish: an example from the English Channel.

PubMed

Molfese, Carlotta; Beare, Doug; Hall-Spencer, Jason M

2014-01-01

The worldwide depletion of major fish stocks through intensive industrial fishing is thought to have profoundly altered the trophic structure of marine ecosystems. Here we assess changes in the trophic structure of the English Channel marine ecosystem using a 90-year time-series (1920-2010) of commercial fishery landings. Our analysis was based on estimates of the mean trophic level (mTL) of annual landings and the Fishing-in-Balance index (FiB). Food webs of the Channel ecosystem have been altered, as shown by a significant decline in the mTL of fishery landings whilst increases in the FiB index suggest increased fishing effort and fishery expansion. Large, high trophic level species (e.g. spurdog, cod, ling) have been increasingly replaced by smaller, low trophic level fish (e.g. small spotted catsharks) and invertebrates (e.g. scallops, crabs and lobster). Declining trophic levels in fisheries catches have occurred worldwide, with fish catches progressively being replaced by invertebrates. We argue that a network of fisheries closures would help rebalance the trophic status of the Channel and allow regeneration of marine ecosystems.

Occurrence and distribution of antifouling biocide Irgarol-1051 in coral reef ecosystems, Zanzibar.

PubMed

Sheikh, Mohammed A; Juma, Fatma S; Staehr, Peter; Dahl, Karsten; Rashid, Rashid J; Mohammed, Mohammed S; Ussi, Ali M; Ali, Hassan R

2016-08-15

2-methythiol-4-tert-butylamino-6-cyclopropylamino-s-triazine (Irgarol-1051) has been widely used as effective alternative antifouling paint in marine structures including ships. However, it has been causing deleterious effects to marine organisms including reef building corals. The main objective of this study was to establish baseline levels of Irgarol-1051 around coral reefs and nearby ecosystems along coastline of Zanzibar Island. The levels of Irgarol-1051 ranged from 1.35ng/L around coral reefs to 15.44ng/L around harbor with average concentration of 4.11 (mean)±0.57 (SD) ng/L. This is below Environmental Risk Limit of 24ng/L as proposed by Dutch Authorities which suggests that the contamination is not alarming especially for coral reef ecosystem health. The main possible sources of the contamination are from shipping activities. This paper provides important baseline information of Irgarol-1051 around the coral reef ecosystems within the Western Indian Ocean (WIO) region and may be useful for formulation of marine conservation strategies and policies. Copyright © 2016 Elsevier Ltd. All rights reserved.

An extreme climatic event alters marine ecosystem structure in a global biodiversity hotspot

NASA Astrophysics Data System (ADS)

Wernberg, Thomas; Smale, Dan A.; Tuya, Fernando; Thomsen, Mads S.; Langlois, Timothy J.; de Bettignies, Thibaut; Bennett, Scott; Rousseaux, Cecile S.

2013-01-01

Extreme climatic events, such as heat waves, are predicted to increase in frequency and magnitude as a consequence of global warming but their ecological effects are poorly understood, particularly in marine ecosystems. In early 2011, the marine ecosystems along the west coast of Australia--a global hotspot of biodiversity and endemism--experienced the highest-magnitude warming event on record. Sea temperatures soared to unprecedented levels and warming anomalies of 2-4°C persisted for more than ten weeks along >2,000km of coastline. We show that biodiversity patterns of temperate seaweeds, sessile invertebrates and demersal fish were significantly different after the warming event, which led to a reduction in the abundance of habitat-forming seaweeds and a subsequent shift in community structure towards a depauperate state and a tropicalization of fish communities. We conclude that extreme climatic events are key drivers of biodiversity patterns and that the frequency and intensity of such episodes have major implications for predictive models of species distribution and ecosystem structure, which are largely based on gradual warming trends.

Ecotoxicology of tropical marine ecosystems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peters, E.C.; Gassman, N.J.; Firman, J.C.

1997-01-01

The negative effects of chemical contaminants on tropical marine ecosystems are of increasing concern as human populations expand adjacent to these communities. Watershed streams and ground water carry a variety of chemicals from agricultural, industrial, and domestic activities, while winds and currents transport pollutants from atmospheric and oceanic sources to these coastal ecosystems. The implications of the limited information available on impacts of chemical stressors on mangrove forests, seagrass meadows, and coral reefs are discussed in the context of ecosystem management and ecological risk assessment. Three classes of pollutants have received attention: heavy metals, petroleum, and synthetic organics. Heavy metalsmore » have been detected in all three ecosystems, causing physiological stress, reduced reproductive success, and outright mortality in associated invertebrates and fishes. Oil spills have been responsible for the destruction of entire coastal shallow-water communities, with recovery requiring years. Herbicides are particularly detrimental to mangroves and seagrasses and adversely affect the animal-algal symbioses in corals. Pesticides interfere with chemical cues responsible for key biological processes, including reproduction and recruitment of a variety of organisms. Information is lacking with regard to long-term recovery, indicator species, and biomarkers for tropical communities. Critical areas that are beginning to be addressed include the development of appropriate benchmarks for risk assessment, baseline monitoring criteria, and effective management strategies to protect tropical marine ecosystems in the face of mounting anthropogenic disturbance.« less

Is economic valuation of ecosystem services useful to decision-makers? Lessons learned from Australian coastal and marine management.

PubMed

Marre, Jean-Baptiste; Thébaud, Olivier; Pascoe, Sean; Jennings, Sarah; Boncoeur, Jean; Coglan, Louisa

2016-08-01

Economic valuation of ecosystem services is widely advocated as being useful to support ecosystem management decision-making. However, the extent to which it is actually used or considered useful in decision-making is poorly documented. This literature blindspot is explored with an application to coastal and marine ecosystems management in Australia. Based on a nation-wide survey of eighty-eight decision-makers representing a diversity of management organizations, the perceived usefulness and level of use of economic valuation of ecosystem services, in support of coastal and marine management, are examined. A large majority of decision-makers are found to be familiar with economic valuation and consider it useful - even necessary - in decision-making, although this varies across groups of decision-makers. However, most decision-makers never or rarely use economic valuation. The perceived level of importance and trust in estimated dollar values differ across ecosystem services, and are especially high for values that relate to commercial activities. A number of factors are also found to influence respondent's use of economic valuation. Such findings concur with conclusions from other studies on the usefulness and use of ESV in environmental management decision-making. They also demonstrate the strength of the survey-based approach developed in this application to examine this issue in a variety of contexts. Copyright © 2016 Elsevier Ltd. All rights reserved.

Early anaerobic metabolisms

PubMed Central

Canfield, Don E; Rosing, Minik T; Bjerrum, Christian

2006-01-01

Before the advent of oxygenic photosynthesis, the biosphere was driven by anaerobic metabolisms. We catalogue and quantify the source strengths of the most probable electron donors and electron acceptors that would have been available to fuel early-Earth ecosystems. The most active ecosystems were probably driven by the cycling of H2 and Fe2+ through primary production conducted by anoxygenic phototrophs. Interesting and dynamic ecosystems would have also been driven by the microbial cycling of sulphur and nitrogen species, but their activity levels were probably not so great. Despite the diversity of potential early ecosystems, rates of primary production in the early-Earth anaerobic biosphere were probably well below those rates observed in the marine environment. We shift our attention to the Earth environment at 3.8 Gyr ago, where the earliest marine sediments are preserved. We calculate, consistent with the carbon isotope record and other considerations of the carbon cycle, that marine rates of primary production at this time were probably an order of magnitude (or more) less than today. We conclude that the flux of reduced species to the Earth surface at this time may have been sufficient to drive anaerobic ecosystems of sufficient activity to be consistent with the carbon isotope record. Conversely, an ecosystem based on oxygenic photosynthesis was also possible with complete removal of the oxygen by reaction with reduced species from the mantle. PMID:17008221

Top 10 principles for designing healthy coastal ecosystems

USGS Publications Warehouse

Gaydos, Joseph K.; Dierauf, Leslie; Kirby, Grant; Brosnan, Deborah; Gilardi, Kirsten; Davis, Gary E.

2008-01-01

Like other coastal zones around the world, the inland sea ecosystem of Washington (USA) and British Columbia (Canada), an area known as the Salish Sea, is changing under pressure from a growing human population, conversion of native forest and shoreline habitat to urban development, toxic contamination of sediments and species, and overharvest of resources. While billions of dollars have been spent trying to restore other coastal ecosystems around the world, there still is no successful model for restoring estuarine or marine ecosystems like the Salish Sea. Despite the lack of a guiding model, major ecological principles do exist that should be applied as people work to design the Salish Sea and other large marine ecosystems for the future. We suggest that the following 10 ecological principles serve as a foundation for educating the public and for designing a healthy Salish Sea and other coastal ecosystems for future generations: (1) Think ecosystem: political boundaries are arbitrary; (2) Account for ecosystem connectivity; (3) Understand the food web; (4) Avoid fragmentation; (5) Respect ecosystem integrity; (6) Support nature's resilience; (7) Value nature: it's money in your pocket; (8) Watch wildlife health; (9) Plan for extremes; and (10) Share the knowledge.

When everything is not everywhere but species evolve: an alternative method to model adaptive properties of marine ecosystems

PubMed Central

Sauterey, Boris; Ward, Ben A.; Follows, Michael J.; Bowler, Chris; Claessen, David

2015-01-01

The functional and taxonomic biogeography of marine microbial systems reflects the current state of an evolving system. Current models of marine microbial systems and biogeochemical cycles do not reflect this fundamental organizing principle. Here, we investigate the evolutionary adaptive potential of marine microbial systems under environmental change and introduce explicit Darwinian adaptation into an ocean modelling framework, simulating evolving phytoplankton communities in space and time. To this end, we adopt tools from adaptive dynamics theory, evaluating the fitness of invading mutants over annual timescales, replacing the resident if a fitter mutant arises. Using the evolutionary framework, we examine how community assembly, specifically the emergence of phytoplankton cell size diversity, reflects the combined effects of bottom-up and top-down controls. When compared with a species-selection approach, based on the paradigm that “Everything is everywhere, but the environment selects”, we show that (i) the selected optimal trait values are similar; (ii) the patterns emerging from the adaptive model are more robust, but (iii) the two methods lead to different predictions in terms of emergent diversity. We demonstrate that explicitly evolutionary approaches to modelling marine microbial populations and functionality are feasible and practical in time-varying, space-resolving settings and provide a new tool for exploring evolutionary interactions on a range of timescales in the ocean. PMID:25852217

When everything is not everywhere but species evolve: an alternative method to model adaptive properties of marine ecosystems.

PubMed

Sauterey, Boris; Ward, Ben A; Follows, Michael J; Bowler, Chris; Claessen, David

2015-01-01

The functional and taxonomic biogeography of marine microbial systems reflects the current state of an evolving system. Current models of marine microbial systems and biogeochemical cycles do not reflect this fundamental organizing principle. Here, we investigate the evolutionary adaptive potential of marine microbial systems under environmental change and introduce explicit Darwinian adaptation into an ocean modelling framework, simulating evolving phytoplankton communities in space and time. To this end, we adopt tools from adaptive dynamics theory, evaluating the fitness of invading mutants over annual timescales, replacing the resident if a fitter mutant arises. Using the evolutionary framework, we examine how community assembly, specifically the emergence of phytoplankton cell size diversity, reflects the combined effects of bottom-up and top-down controls. When compared with a species-selection approach, based on the paradigm that "Everything is everywhere, but the environment selects", we show that (i) the selected optimal trait values are similar; (ii) the patterns emerging from the adaptive model are more robust, but (iii) the two methods lead to different predictions in terms of emergent diversity. We demonstrate that explicitly evolutionary approaches to modelling marine microbial populations and functionality are feasible and practical in time-varying, space-resolving settings and provide a new tool for exploring evolutionary interactions on a range of timescales in the ocean.

A Novel Enzyme Portfolio for Red Algal Polysaccharide Degradation in the Marine Bacterium Paraglaciecola hydrolytica S66T Encoded in a Sizeable Polysaccharide Utilization Locus.

PubMed

Schultz-Johansen, Mikkel; Bech, Pernille K; Hennessy, Rosanna C; Glaring, Mikkel A; Barbeyron, Tristan; Czjzek, Mirjam; Stougaard, Peter

2018-01-01

Marine microbes are a rich source of enzymes for the degradation of diverse polysaccharides. Paraglaciecola hydrolytica S66 T is a marine bacterium capable of hydrolyzing polysaccharides found in the cell wall of red macroalgae. In this study, we applied an approach combining genomic mining with functional analysis to uncover the potential of this bacterium to produce enzymes for the hydrolysis of complex marine polysaccharides. A special feature of P. hydrolytica S66 T is the presence of a large genomic region harboring an array of carbohydrate-active enzymes (CAZymes) notably agarases and carrageenases. Based on a first functional characterization combined with a comparative sequence analysis, we confirmed the enzymatic activities of several enzymes required for red algal polysaccharide degradation by the bacterium. In particular, we report for the first time, the discovery of novel enzyme activities targeting furcellaran, a hybrid carrageenan containing both β-carrageenan and κ/β-carrageenan motifs. Some of these enzymes represent a new subfamily within the CAZy classification. From the combined analyses, we propose models for the complete degradation of agar and κ/β-type carrageenan by P. hydrolytica S66 T . The novel enzymes described here may find value in new bio-based industries and advance our understanding of the mechanisms responsible for recycling of red algal polysaccharides in marine ecosystems.

Remote sensing of Essential Biodiversity Variables: new measurements linking ecosystem structure, function and composition

NASA Astrophysics Data System (ADS)

Schimel, D.; Pavlick, R.; Stavros, E. N.; Townsend, P. A.; Ustin, S.; Thompson, D. R.

2017-12-01

Remote sensing can inform a wide variety of essential biodiversity variables, including measurements that define primary productivity, forest structure, biome distribution, plant communities, land use-land cover change and climate drivers of change. Emerging remote sensing technologies can add significantly to remote sensing of EBVs, providing new, large scale insights on plant and habitat diversity itself, as well as causes and consequences of biodiversity change. All current biodiversity assessments identify major data gaps, with insufficient coverage in critical regions, limited observations to monitor change over time, with very limited revisit of sample locations, as well as taxon-specific biased biases. Remote sensing cannot fill many of the gaps in global biodiversity observations, but spectroscopic measurements in terrestrial and marine environments can aid in assessing plant/phytoplankton functional diversity and efficiently reveal patterns in space, as well as changes over time, and, by making use of chlorophyll fluorescence, reveal associated patterns in photosynthesis. LIDAR and RADAR measurements quantify ecosystem structure, and can precisely define changes due to growth, disturbance and land use. Current satellite-based EBVs have taken advantage of the extraordinary time series from LANDSAT and MODIS, but new measurements more directly reveal ecosystem structure, function and composition. We will present results from pre-space airborne studies showing the synergistic ability of a suite of new remote observation techniques to quantify biodiversity and ecosystem function and show how it changes during major disturbance events.

Tracing biogeochemical subsidies from glacier runoff into Alaska's coastal marine food webs

USGS Publications Warehouse

Arimitsu, Mayumi L.; Hobson, Keith A.; Webber, D'Arcy N.; Piatt, John F.; Hood, Eran W.; Fellman, Jason B.

2018-01-01

Nearly half of the freshwater discharge into the Gulf of Alaska originates from landscapes draining glacier runoff, but the influence of the influx of riverine organic matter on the trophodynamics of coastal marine food webs is not well understood. We quantified the ecological impact of riverine organic matter subsidies to glacier-marine habitats by developing a multi-trophic level Bayesian three-isotope mixing model. We utilized large gradients in stable (δ13C, δ15N, δ2H) and radiogenic (Δ14C) isotopes that trace riverine and marine organic matter sources as they are passed from lower to higher trophic levels in glacial-marine habitats. We also compared isotope ratios between glacial-marine and more oceanic habitats. Based on isotopic measurements of potential baseline sources, ambient water and tissues of marine consumers, estimates of the riverine organic matter source contribution to upper trophic-level species including fish and seabirds ranged from 12% to 44%. Variability in resource use among similar taxa corresponded to variation in species distribution and life histories. For example, riverine organic matter assimilation by the glacier-nesting seabirds Kittlitz's murrelet (Brachyramphus brevirostris) was greater than that of the forest-nesting marbled murrelet (B. marmoratus). The particulate and dissolved organic carbon in glacial runoff and near surface coastal waters was aged (12100–1500 years BP 14C-age) but dissolved inorganic carbon and biota in coastal waters were young (530 years BP 14C-age to modern). Thus terrestrial-derived subsidies in marine food webs were primarily composed of young organic matter sources released from glacier ecosystems and their surrounding watersheds. Stable isotope compositions also revealed a divergence in food web structure between glacial-marine and oceanic sites. This work demonstrates linkages between terrestrial and marine ecosystems, and facilitates a greater understanding of how climate-driven changes in freshwater runoff have the potential to alter food web dynamics within coastal marine ecosystems in Alaska.

The Food Web of Potter Cove (Antarctica): complexity, structure and function

NASA Astrophysics Data System (ADS)

Marina, Tomás I.; Salinas, Vanesa; Cordone, Georgina; Campana, Gabriela; Moreira, Eugenia; Deregibus, Dolores; Torre, Luciana; Sahade, Ricardo; Tatián, Marcos; Barrera Oro, Esteban; De Troch, Marleen; Doyle, Santiago; Quartino, María Liliana; Saravia, Leonardo A.; Momo, Fernando R.

2018-01-01

Knowledge of the food web structure and complexity are central to better understand ecosystem functioning. A food-web approach includes both species and energy flows among them, providing a natural framework for characterizing species' ecological roles and the mechanisms through which biodiversity influences ecosystem dynamics. Here we present for the first time a high-resolution food web for a marine ecosystem at Potter Cove (northern Antarctic Peninsula). Eleven food web properties were analyzed in order to document network complexity, structure and topology. We found a low linkage density (3.4), connectance (0.04) and omnivory percentage (45), as well as a short path length (1.8) and a low clustering coefficient (0.08). Furthermore, relating the structure of the food web to its dynamics, an exponential degree distribution (in- and out-links) was found. This suggests that the Potter Cove food web may be vulnerable if the most connected species became locally extinct. For two of the three more connected functional groups, competition overlap graphs imply high trophic interaction between demersal fish and niche specialization according to feeding strategies in amphipods. On the other hand, the prey overlap graph shows also that multiple energy pathways of carbon flux exist across benthic and pelagic habitats in the Potter Cove ecosystem. Although alternative food sources might add robustness to the web, network properties (low linkage density, connectance and omnivory) suggest fragility and potential trophic cascade effects.

Ecosystem Encounters: Lessons in Synthetic Ecology.

ERIC Educational Resources Information Center

Adey, Walter H.

1992-01-01

The director of the Marine Systems Laboratory of the Smithsonian Institution discusses steps in developing ecological models. The following topics in using an aquarium for the ecosystem are described: lighting, water motion, water quality and filtration. Presents information on choosing living organisms for the ecosystem. Describes potential…

40 CFR 300.600 - Designation of federal trustees.

Code of Federal Regulations, 2014 CFR

2014-07-01

... resources, including their supporting ecosystems. They are authorized to act pursuant to section 107(f) of..., loss of, or threat to natural resources, including their supporting ecosystems, as a result of a... following natural resources and their supporting ecosystems: marine fishery resources; anadromous fish...

40 CFR 300.600 - Designation of federal trustees.

Code of Federal Regulations, 2013 CFR

2013-07-01

... resources, including their supporting ecosystems. They are authorized to act pursuant to section 107(f) of..., loss of, or threat to natural resources, including their supporting ecosystems, as a result of a... following natural resources and their supporting ecosystems: marine fishery resources; anadromous fish...

40 CFR 300.600 - Designation of federal trustees.

Code of Federal Regulations, 2012 CFR

2012-07-01

... resources, including their supporting ecosystems. They are authorized to act pursuant to section 107(f) of..., loss of, or threat to natural resources, including their supporting ecosystems, as a result of a... following natural resources and their supporting ecosystems: marine fishery resources; anadromous fish...

40 CFR 300.600 - Designation of federal trustees.

Code of Federal Regulations, 2011 CFR

2011-07-01

... resources, including their supporting ecosystems. They are authorized to act pursuant to section 107(f) of..., loss of, or threat to natural resources, including their supporting ecosystems, as a result of a... following natural resources and their supporting ecosystems: marine fishery resources; anadromous fish...

Modeling of the nearshore marine ecosystem with the AQUATOX model

EPA Science Inventory

Process-based models can be used to forecast the responses of coastal ecosystems to changes under future scenarios. However, most models applied to coastal systems do not include higher trophic levels, which are important providers of ecosystem services. AQUATOX is a mechanistic...

The role of sustained observations in tracking impacts of environmental change on marine biodiversity and ecosystems.

PubMed

Mieszkowska, N; Sugden, H; Firth, L B; Hawkins, S J

2014-09-28

Marine biodiversity currently faces unprecedented threats from multiple pressures arising from human activities. Global drivers such as climate change and ocean acidification interact with regional eutrophication, exploitation of commercial fish stocks and localized pressures including pollution, coastal development and the extraction of aggregates and fuel, causing alteration and degradation of habitats and communities. Segregating natural from anthropogenically induced change in marine ecosystems requires long-term, sustained observations of marine biota. In this review, we outline the history of biological recording in the coastal and shelf seas of the UK and Ireland and highlight where sustained observations have contributed new understanding of how anthropogenic activities have impacted on marine biodiversity. The contributions of sustained observations, from those collected at observatories, single station platforms and multiple-site programmes to the emergent field of multiple stressor impacts research, are discussed, along with implications for management and sustainable governance of marine resources in an era of unprecedented use of the marine environment. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Climate change can cause complex responses in Baltic Sea macroalgae: A systematic review

NASA Astrophysics Data System (ADS)

Takolander, Antti; Cabeza, Mar; Leskinen, Elina

2017-05-01

Estuarine macroalgae are important primary producers in aquatic ecosystems, and often foundation species providing structurally complex habitat. Climate change alters many abiotic factors that affect their long-term persistence and distribution. Here, we review the existing scientific literature on the tolerance of key macroalgal species in the Baltic Sea, the world's largest brackish water body. Elevated temperature is expected to intensify coastal eutrophication, further promoting growth of opportunistic, filamentous species, especially green algae, which are often species associated with intensive filamentous algal blooms. Declining salinities will push the distributions of marine species towards south, which may alter the Baltic Sea community compositions towards a more limnic state. Together with increasing eutrophication trends this may cause losses in marine-originating foundation species such as Fucus, causing severe biodiversity impacts. Experimental results on ocean acidification effects on macroalgae are mixed, with only few studies conducted in the Baltic Sea. We conclude that climate change can alter the structure and functioning of macroalgal ecosystems especially in the northern Baltic coastal areas, and can potentially act synergistically with eutrophication. We briefly discuss potential adaptation measures.

BaP-metals co-exposure induced tissue-specific antioxidant defense in marine mussels Mytilus coruscus.

PubMed

Chen, Siyu; Qu, Mengjie; Ding, Jiawei; Zhang, Yifei; Wang, Yi; Di, Yanan

2018-04-18

Both benzo(α)pyrene (BaP) and metals are frequently found in marine ecosystem and can cause detrimental effects in marine organism, especially the filter feeder-marine mussels. Although the biological responses in mussels have been well-studied upon the single metal or BaP exposure, the information about antioxidant defense, especially in different tissues of mussels, are still limited. Considering the variety of contaminants existing in the actual marine environment, single BaP (56 μg/L) and the co-exposure with Cu, Cd and Pb (50 μg/L, 50 μg/L and 3 mg/L respectively) were applied in a 6 days exposure followed by 6 days depuration experiment. The alterations of superoxide dismutase (SOD), catalase (CAT) activities and total antioxidant capacity (TAC) level were assessed in haemolymph, gills and digestive glands of marine mussels, Mytilus coruscus. An unparalleled change in antioxidant biomarkers was observed in all cells/tissues, with the SOD activity showing higher sensitivity to exposure. A tissue-specific response showing unique alteration in gill was investigated, indicating the different function of tissues during stress responses. Depressed antioxidant effects were induced by BaP-metals co-exposure, indicating the interaction may alter the intact properties of BaP. To our knowledge, this is the first research to explore the antioxidant defense induced by combined exposure of BaP-metals regarding to tissue-specific responses in marine mussels. The results and experimental model will provide valuable information and can be utilized in the investigation of stress response mechanisms, especially in relation to tissue functions in marine organism in the future. Copyright © 2018 Elsevier Ltd. All rights reserved.

Examining predator–prey body size, trophic level and body mass across marine and terrestrial mammals

PubMed Central

Tucker, Marlee A.; Rogers, Tracey L.

2014-01-01

Predator–prey relationships and trophic levels are indicators of community structure, and are important for monitoring ecosystem changes. Mammals colonized the marine environment on seven separate occasions, which resulted in differences in species' physiology, morphology and behaviour. It is likely that these changes have had a major effect upon predator–prey relationships and trophic position; however, the effect of environment is yet to be clarified. We compiled a dataset, based on the literature, to explore the relationship between body mass, trophic level and predator–prey ratio across terrestrial (n = 51) and marine (n = 56) mammals. We did not find the expected positive relationship between trophic level and body mass, but we did find that marine carnivores sit 1.3 trophic levels higher than terrestrial carnivores. Also, marine mammals are largely carnivorous and have significantly larger predator–prey ratios compared with their terrestrial counterparts. We propose that primary productivity, and its availability, is important for mammalian trophic structure and body size. Also, energy flow and community structure in the marine environment are influenced by differences in energy efficiency and increased food web stability. Enhancing our knowledge of feeding ecology in mammals has the potential to provide insights into the structure and functioning of marine and terrestrial communities. PMID:25377460

Unraveling the intricate dynamics of planktonic Arctic marine food webs. A sensitivity analysis of a well-documented food web model

NASA Astrophysics Data System (ADS)

Saint-Béat, Blanche; Maps, Frédéric; Babin, Marcel

2018-01-01

The extreme and variable environment shapes the functioning of Arctic ecosystems and the life cycles of its species. This delicate balance is now threatened by the unprecedented pace and magnitude of global climate change and anthropogenic pressure. Understanding the long-term consequences of these changes remains an elusive, yet pressing, goal. Our work was specifically aimed at identifying which biological processes impact Arctic planktonic ecosystem functioning, and how. Ecological Network Analysis (ENA) indices reveal emergent ecosystem properties that are not accessible through simple in situ observation. These indices are based on the architecture of carbon flows within food webs. But, despite the recent increase in in situ measurements from Arctic seas, many flow values remain unknown. Linear inverse modeling (LIM) allows missing flow values to be estimated from existing flow observations and, subsequent reconstruction of ecosystem food webs. Through a sensitivity analysis on a LIM model of the Amundsen Gulf in the Canadian Arctic, we were able to determine which processes affected the emergent properties of the planktonic ecosystem. The analysis highlighted the importance of an accurate knowledge of the various processes controlling bacterial production (e.g. bacterial growth efficiency and viral lysis). More importantly, a change in the fate of the microzooplankton within the food web can be monitored through the trophic level of mesozooplankton. It can be used as a "canary in the coal mine" signal, a forewarner of larger ecosystem change.

Transfer of marine mercury to mountain lakes.

PubMed

Hansson, Sophia V; Sonke, Jeroen; Galop, Didier; Bareille, Gilles; Jean, Séverine; Le Roux, Gaël

2017-10-05

Stocking is a worldwide activity on geographical and historical scales. The rate of non-native fish introductions have more than doubled over the last decades yet the effect on natural ecosystems, in the scope of biologically mediated transport and biomagnification of Hg and Hg-isotopes, is unknown. Using geochemistry (THg) and stable isotopes (N, Sr and Hg), we evaluate natal origin and trophic position of brown trout (Salmo trutta fario), as well as mercury biomagnification trends and potential pollution sources to three high-altitude lakes. Farmed trout show Hg-isotope signatures similar to marine biota whereas wild trout shows Hg-isotope signatures typical of fresh water lakes. Stocked trout initially show Hg-isotope signatures similar to marine biota. As the stocked trout age and shifts diet to a higher trophic level, THg concentrations increase and the marine Hg isotope signatures, induced via farm fish feed, shift to locally produced MeHg with lower δ 202 Hg and higher Δ 199 Hg. We conclude that stocking acts a humanly induced biovector that transfers marine Hg to freshwater ecosystems, which is seen in the Hg-isotopic signature up to five years after stocking events occurred. This points to the need of further investigations of the role of stocking in MeHg exposure to freshwater ecosystems.

A new classification scheme of European cold-water coral habitats: Implications for ecosystem-based management of the deep sea

NASA Astrophysics Data System (ADS)

Davies, J. S.; Guillaumont, B.; Tempera, F.; Vertino, A.; Beuck, L.; Ólafsdóttir, S. H.; Smith, C. J.; Fosså, J. H.; van den Beld, I. M. J.; Savini, A.; Rengstorf, A.; Bayle, C.; Bourillet, J.-F.; Arnaud-Haond, S.; Grehan, A.

2017-11-01

Cold-water corals (CWC) can form complex structures which provide refuge, nursery grounds and physical support for a diversity of other living organisms. However, irrespectively from such ecological significance, CWCs are still vulnerable to human pressures such as fishing, pollution, ocean acidification and global warming Providing coherent and representative conservation of vulnerable marine ecosystems including CWCs is one of the aims of the Marine Protected Areas networks being implemented across European seas and oceans under the EC Habitats Directive, the Marine Strategy Framework Directive and the OSPAR Convention. In order to adequately represent ecosystem diversity, these initiatives require a standardised habitat classification that organises the variety of biological assemblages and provides consistent and functional criteria to map them across European Seas. One such classification system, EUNIS, enables a broad level classification of the deep sea based on abiotic and geomorphological features. More detailed lower biotope-related levels are currently under-developed, particularly with regards to deep-water habitats (>200 m depth). This paper proposes a hierarchical CWC biotope classification scheme that could be incorporated by existing classification schemes such as EUNIS. The scheme was developed within the EU FP7 project CoralFISH to capture the variability of CWC habitats identified using a wealth of seafloor imagery datasets from across the Northeast Atlantic and Mediterranean. Depending on the resolution of the imagery being interpreted, this hierarchical scheme allows data to be recorded from broad CWC biotope categories down to detailed taxonomy-based levels, thereby providing a flexible yet valuable information level for management. The CWC biotope classification scheme identifies 81 biotopes and highlights the limitations of the classification framework and guidance provided by EUNIS, the EC Habitats Directive, OSPAR and FAO; which largely underrepresent CWC habitats.

Using Knowledge of Chemical and Structural Defenses of Seaweeds to Develop a Standardized Measure of Herbivory in Tropical and Subtropical Habitats

NASA Astrophysics Data System (ADS)

Paul, V. J.

2016-02-01

Herbivory is an important process determining the structure and function of marine ecosystems, and this is especially true on coral reefs and in associated tropical and subtropical habitats where grazing by fishes can be intense. As reef degradation is occurring on a global scale, and overfishing can contribute to this problem, rates of herbivory can be an important indicator of reef function and resilience. Our goal was to develop a standardized herbivory assay that can be deployed globally to measure the impact of herbivorous fishes across multiple habitat types. Many tropical and subtropical seaweeds contain chemical and structural defenses that can protect them from herbivores, and this information was key to selecting a range of marine plants that are differentially palatable to herbivorous fishes for these assays. We present method development and experimental results from extensive deployment of these herbivory assays at Carrie Bow Cay, Belize.

Indonesia's globally significant seagrass meadows are under widespread threat.

PubMed

Unsworth, Richard K F; Ambo-Rappe, Rohani; Jones, Benjamin L; La Nafie, Yayu A; Irawan, A; Hernawan, Udhi E; Moore, Abigail M; Cullen-Unsworth, Leanne C

2018-09-01

Indonesia's marine ecosystems form a fundamental part of the world's natural heritage, representing a global maxima of marine biodiversity and supporting the world's second largest production of seafood. Seagrasses are a key part of that support. In the absence of empirical data we present evidence from expert opinions as to the state of Indonesia's seagrass ecosystems, their support for ecosystem services, with a focus on fisheries, and the damaging activities that threaten their existence. We further draw on expert opinion to elicit potential solutions to prevent further loss. Seagrasses and the ecosystem services they support across the Indonesian archipelago are in a critical state of decline. Declining seagrass health is the result of shifting environmental conditions due largely to coastal development, land reclamation, and deforestation, as well as seaweed farming, overfishing and garbage dumping. In particular, we also describe the declining state of the fisheries resources that seagrass meadows support. The perilous state of Indonesia's seagrasses will compromise their resilience to climate change and result in a loss of their high ecosystem service value. Community supported management initiatives provide one mechanism for seagrass protection. Exemplars highlight the need for increased local level autonomy for the management of marine resources, opening up opportunities for incentive type conservation schemes. Copyright © 2018 Elsevier B.V. All rights reserved.

Human activities change marine ecosystems by altering predation risk.

PubMed

Madin, Elizabeth M P; Dill, Lawrence M; Ridlon, April D; Heithaus, Michael R; Warner, Robert R

2016-01-01

In ocean ecosystems, many of the changes in predation risk - both increases and decreases - are human-induced. These changes are occurring at scales ranging from global to local and across variable temporal scales. Indirect, risk-based effects of human activity are known to be important in structuring some terrestrial ecosystems, but these impacts have largely been neglected in oceans. Here, we synthesize existing literature and data to explore multiple lines of evidence that collectively suggest diverse human activities are changing marine ecosystems, including carbon storage capacity, in myriad ways by altering predation risk. We provide novel, compelling evidence that at least one key human activity, overfishing, can lead to distinct, cascading risk effects in natural ecosystems whose magnitude exceeds that of presumed lethal effects and may account for previously unexplained findings. We further discuss the conservation implications of human-caused indirect risk effects. Finally, we provide a predictive framework for when human alterations of risk in oceans should lead to cascading effects and outline a prospectus for future research. Given the speed and extent with which human activities are altering marine risk landscapes, it is crucial that conservation and management policy considers the indirect effects of these activities in order to increase the likelihood of success and avoid unfortunate surprises. © 2015 John Wiley & Sons Ltd.

Natural variability of marine ecosystems inferred from a coupled climate to ecosystem simulation

NASA Astrophysics Data System (ADS)

Le Mézo, Priscilla; Lefort, Stelly; Séférian, Roland; Aumont, Olivier; Maury, Olivier; Murtugudde, Raghu; Bopp, Laurent

2016-01-01

This modeling study analyzes the simulated natural variability of pelagic ecosystems in the North Atlantic and North Pacific. Our model system includes a global Earth System Model (IPSL-CM5A-LR), the biogeochemical model PISCES and the ecosystem model APECOSM that simulates upper trophic level organisms using a size-based approach and three interactive pelagic communities (epipelagic, migratory and mesopelagic). Analyzing an idealized (e.g., no anthropogenic forcing) 300-yr long pre-industrial simulation, we find that low and high frequency variability is dominant for the large and small organisms, respectively. Our model shows that the size-range exhibiting the largest variability at a given frequency, defined as the resonant range, also depends on the community. At a given frequency, the resonant range of the epipelagic community includes larger organisms than that of the migratory community and similarly, the latter includes larger organisms than the resonant range of the mesopelagic community. This study shows that the simulated temporal variability of marine pelagic organisms' abundance is not only influenced by natural climate fluctuations but also by the structure of the pelagic community. As a consequence, the size- and community-dependent response of marine ecosystems to climate variability could impact the sustainability of fisheries in a warming world.