Science.gov

Sample records for change marine rocky

  1. Introduced rats indirectly change marine rocky intertidal communities from algae- to invertebrate-dominated.

    PubMed

    Kurle, Carolyn M; Croll, Donald A; Tershy, Bernie R

    2008-03-11

    It is widely recognized that trophic interactions structure ecological communities, but their effects are usually only demonstrated on a small scale. As a result, landscape-level documentations of trophic cascades that alter entire communities are scarce. Islands invaded by animals provide natural experiment opportunities both to measure general trophic effects across large spatial scales and to determine the trophic roles of invasive species within native ecosystems. Studies addressing the trophic interactions of invasive species most often focus on their direct effects. To investigate both the presence of a landscape-level trophic cascade and the direct and indirect effects of an invasive species, we examined the impacts of Norway rats (Rattus norvegicus) introduced to the Aleutian Islands on marine bird densities and marine rocky intertidal community structures through surveys conducted on invaded and rat-free islands throughout the entire 1,900-km archipelago. Densities of birds that forage in the intertidal were higher on islands without rats. Marine intertidal invertebrates were more abundant on islands with rats, whereas fleshy algal cover was reduced. Our results demonstrate that invasive rats directly reduce bird densities through predation and significantly affect invertebrate and marine algal abundance in the rocky intertidal indirectly via a cross-community trophic cascade, unexpectedly changing the intertidal community structure from an algae- to an invertebrate-dominated system.

  2. Marine reserves reestablish lost predatory interactions and cause community changes in rocky reefs.

    PubMed

    Guidetti, Paolo

    2006-06-01

    In the last decades, marine reserves have dramatically increased in number worldwide. Here I examined the potential of no-take marine reserves to reestablish lost predatory interactions and, in turn, cause community-wide changes in Mediterranean rocky reefs. Protected locations supported higher density and size of the most effective fish preying on sea urchins (the sea breams Diplodus sargus and D. vulgaris) than unprotected locations. Density of sea urchins (Paracentrotus lividus and Arbacia lixula) was lower at protected than at unprotected locations. Size structure of P. lividus was bimodal (a symptom of predation on medium-sized urchins) only at the protected locations. Coralline barrens were less extended at protected than at unprotected locations, whereas turf-forming and erect-branched algae showed an opposite pattern. Erect-unbranched and erect-calcified algae and conspicuous zoobenthic organisms did not show any pattern related to protection. Tethering experiments showed that predation impact on urchins was (1) higher at protected than at unprotected locations, (2) higher on P. lividus than on A. lixula, and (3) higher on medium-sized (2-3.5 cm test diameter) than large-sized (>3.5 cm) urchins. Sea urchins preyed on by fish in natural conditions were smaller at unprotected than at protected locations. The analysis of sea urchin remains found in Diplodus fish stomachs revealed that medium-sized P. lividus were the most frequently preyed upon urchins and that size range of consumed sea urchins expanded with increasing size of Diplodus fish. These results suggest that (1) depletion and size reduction of predatory fish caused by fishing alter patterns of predation on sea urchins, and that (2) fishing bans (e.g., within no-take marine reserves) may reestablish lost interactions among strongly interactive species in temperate rocky reefs with potential community-wide effects.

  3. Sampling design for long-term regional trends in marine rocky intertidal communities

    USGS Publications Warehouse

    Irvine, Gail V.; Shelley, Alice

    2013-01-01

    Probability-based designs reduce bias and allow inference of results to the pool of sites from which they were chosen. We developed and tested probability-based designs for monitoring marine rocky intertidal assemblages at Glacier Bay National Park and Preserve (GLBA), Alaska. A multilevel design was used that varied in scale and inference. The levels included aerial surveys, extensive sampling of 25 sites, and more intensive sampling of 6 sites. Aerial surveys of a subset of intertidal habitat indicated that the original target habitat of bedrock-dominated sites with slope ≤30° was rare. This unexpected finding illustrated one value of probability-based surveys and led to a shift in the target habitat type to include steeper, more mixed rocky habitat. Subsequently, we evaluated the statistical power of different sampling methods and sampling strategies to detect changes in the abundances of the predominant sessile intertidal taxa: barnacles Balanomorpha, the mussel Mytilus trossulus, and the rockweed Fucus distichus subsp. evanescens. There was greatest power to detect trends in Mytilus and lesser power for barnacles and Fucus. Because of its greater power, the extensive, coarse-grained sampling scheme was adopted in subsequent years over the intensive, fine-grained scheme. The sampling attributes that had the largest effects on power included sampling of “vertical” line transects (vs. horizontal line transects or quadrats) and increasing the number of sites. We also evaluated the power of several management-set parameters. Given equal sampling effort, sampling more sites fewer times had greater power. The information gained through intertidal monitoring is likely to be useful in assessing changes due to climate, including ocean acidification; invasive species; trampling effects; and oil spills.

  4. Sampling design for long-term regional trends in marine rocky intertidal communities.

    PubMed

    Irvine, Gail V; Shelly, Alice

    2013-08-01

    Probability-based designs reduce bias and allow inference of results to the pool of sites from which they were chosen. We developed and tested probability-based designs for monitoring marine rocky intertidal assemblages at Glacier Bay National Park and Preserve (GLBA), Alaska. A multilevel design was used that varied in scale and inference. The levels included aerial surveys, extensive sampling of 25 sites, and more intensive sampling of 6 sites. Aerial surveys of a subset of intertidal habitat indicated that the original target habitat of bedrock-dominated sites with slope ≤30° was rare. This unexpected finding illustrated one value of probability-based surveys and led to a shift in the target habitat type to include steeper, more mixed rocky habitat. Subsequently, we evaluated the statistical power of different sampling methods and sampling strategies to detect changes in the abundances of the predominant sessile intertidal taxa: barnacles Balanomorpha, the mussel Mytilus trossulus, and the rockweed Fucus distichus subsp. evanescens. There was greatest power to detect trends in Mytilus and lesser power for barnacles and Fucus. Because of its greater power, the extensive, coarse-grained sampling scheme was adopted in subsequent years over the intensive, fine-grained scheme. The sampling attributes that had the largest effects on power included sampling of "vertical" line transects (vs. horizontal line transects or quadrats) and increasing the number of sites. We also evaluated the power of several management-set parameters. Given equal sampling effort, sampling more sites fewer times had greater power. The information gained through intertidal monitoring is likely to be useful in assessing changes due to climate, including ocean acidification; invasive species; trampling effects; and oil spills.

  5. Habitat Discontinuities Separate Genetically Divergent Populations of a Rocky Shore Marine Fish

    PubMed Central

    Knutsen, Halvor; Jorde, Per Erik

    2016-01-01

    Habitat fragmentation has been suggested to be responsible for major genetic differentiations in a range of marine organisms. In this study, we combined genetic data and environmental information to unravel the relative role of geography and habitat heterogeneity on patterns of genetic population structure of corkwing wrasse (Symphodus melops), a rocky shore species at the northern limit of its distribution range in Scandinavia. Our results revealed a major genetic break separating populations inhabiting the western and southern coasts of Norway. This genetic break coincides with the longest stretch of sand in the whole study area, suggesting habitat fragmentation as a major driver of genetic differentiation of this obligate rocky shore benthic fish in Scandinavia. The complex fjords systems extending along the western coast of Norway appeared responsible for further regional genetic structuring. Our findings indicate that habitat discontinuities may lead to significant genetic fragmentation over short geographical distances, even for marine species with a pelagic larval phase, as for this rocky shore fish. PMID:27706178

  6. Genetic Structuring across Marine Biogeographic Boundaries in Rocky Shore Invertebrates

    PubMed Central

    Villamor, Adriana; Costantini, Federica; Abbiati, Marco

    2014-01-01

    Biogeography investigates spatial patterns of species distribution. Discontinuities in species distribution are identified as boundaries between biogeographic areas. Do these boundaries affect genetic connectivity? To address this question, a multifactorial hierarchical sampling design, across three of the major marine biogeographic boundaries in the central Mediterranean Sea (Ligurian-Tyrrhenian, Tyrrhenian-Ionian and Ionian-Adriatic) was carried out. Mitochondrial COI sequence polymorphism of seven species of Mediterranean benthic invertebrates was analysed. Two species showed significant genetic structure across the Tyrrhenian-Ionian boundary, as well as two other species across the Ionian Sea, a previously unknown phylogeographic barrier. The hypothesized barrier in the Ligurian-Tyrrhenian cannot be detected in the genetic structure of the investigated species. Connectivity patterns across species at distances up to 800 km apart confirmed that estimates of pelagic larval dispersal were poor predictors of the genetic structure. The detected genetic discontinuities seem more related to the effect of past historical events, though maintained by present day oceanographic processes. Multivariate statistical tools were used to test the consistency of the patterns across species, providing a conceptual framework for across-species barrier locations and strengths. Additional sequences retrieved from public databases supported our findings. Heterogeneity of phylogeographic patterns shown by the 7 investigated species is relevant to the understanding of the genetic diversity, and carry implications for conservation biology. PMID:24983738

  7. Genetic structuring across marine biogeographic boundaries in rocky shore invertebrates.

    PubMed

    Villamor, Adriana; Costantini, Federica; Abbiati, Marco

    2014-01-01

    Biogeography investigates spatial patterns of species distribution. Discontinuities in species distribution are identified as boundaries between biogeographic areas. Do these boundaries affect genetic connectivity? To address this question, a multifactorial hierarchical sampling design, across three of the major marine biogeographic boundaries in the central Mediterranean Sea (Ligurian-Tyrrhenian, Tyrrhenian-Ionian and Ionian-Adriatic) was carried out. Mitochondrial COI sequence polymorphism of seven species of Mediterranean benthic invertebrates was analysed. Two species showed significant genetic structure across the Tyrrhenian-Ionian boundary, as well as two other species across the Ionian Sea, a previously unknown phylogeographic barrier. The hypothesized barrier in the Ligurian-Tyrrhenian cannot be detected in the genetic structure of the investigated species. Connectivity patterns across species at distances up to 800 km apart confirmed that estimates of pelagic larval dispersal were poor predictors of the genetic structure. The detected genetic discontinuities seem more related to the effect of past historical events, though maintained by present day oceanographic processes. Multivariate statistical tools were used to test the consistency of the patterns across species, providing a conceptual framework for across-species barrier locations and strengths. Additional sequences retrieved from public databases supported our findings. Heterogeneity of phylogeographic patterns shown by the 7 investigated species is relevant to the understanding of the genetic diversity, and carry implications for conservation biology.

  8. Monitoring forest change at ecotones in the Colorado Rockies

    SciTech Connect

    Stohlgren, T.J.; Bachand, R.R. )

    1994-06-01

    We are assessing the potential effect of global climate change on the Front Range of the Colorado Rockies, including Rocky Mountain National Park. Our objective is quantify the abiotic and biotic controls on forest distribution and productivity as a basis for assessing potential vegetation change for a range of projected climate scenarios. A series of long-term vegetation transects are being established to relate soil characteristics (e.g., soil type, texture, moisture, nitrogen content) and microclimate (air and soil temperature) to vegetation characteristics (e.g., basal area, leaf area index, tree age structure, resource use efficiency, primary production) across lodgepole pine (Pinus contorta var. latifolia) ecotones. Results from five 200+ ectonal transects (68 20 m x 20 m plots; over 3,753 trees) show that basal area gradients from lodgepole pine to spruce-fir (Picea engelmannii, Abies lasiocarpa), ponderosa pine (Pinus ponderosa), and limber pine (Pinus flexilis) forests are correlated strongly (but not linearly), to soil texture and summer soil moisture. Factors controlling species-specific radial growth patterns along ecotones are more complex.

  9. Effects of marine reserves and urchin disease on southern Californian rocky reef communities

    USGS Publications Warehouse

    Behrens, Michael D.; Lafferty, Kevin D.

    2004-01-01

    While the species level effects of marine reserves are widely recognized, community level shifts due to marine reserves have only recently been documented. Protection from fishing of top predators may lead to trophic cascades, which have community-wide implications. Disease may act in a similar manner, regulating population levels of dominant species within a community. Two decades of data from the Channel Islands National Park Service's Kelp Forest Monitoring database allowed us to compare the effects of fishing and urchin disease on rocky reef community patterns and dynamics. Different size-frequency distributions of urchins inside and outside of reserves indicated reduced predation on urchins at sites where fishing removes urchin predators. Rocky reefs inside reserves were more likely to support kelp forests than were fished areas. We suggest that this results from cascading effects of the fishery on urchin predators outside the reserves, which releases herbivores (urchins) from predation. After periods of prevalent urchin disease, the reef community shifted more towards kelp forest assemblages. Specific groups of algae and invertebrates were associated with kelp forest and barrens communities. The community dynamics leading to transitions between kelp forests and barrens are driven by both fishing and disease; however the fishery effect was of greater magnitude. This study further confirms the importance of marine reserves not only for fisheries conservation, but also for the conservation of historically dominant community types.

  10. Change analysis of karst rocky desertification for almost 40 years: a case study of Guangxi, China

    NASA Astrophysics Data System (ADS)

    Wang, Wei; Zhou, Guoqing; Mao, Guodong; Shi, Yujun; Zhang, Rongting; Su, Chengjie

    2015-12-01

    The paper first studied the geometric correction of historical CORONA satellite imagery in the 1960s and used the historical imagery to extract KRD (karst rocky desertification). The study area is located in the karst region of Guangxi Province, China. Finally, we used the Landsat-5 imagery to extract rocky desertification in 2005, then we could find the changes of the karst rocky desertification in Guangxi from 1960s to 2005 about nearly 40 years. And comparison analysis was conducted and the results showed that, over the 40 years, Guangxi karst rocky desertification area has significantly changed. Guangxi has typical karst environment and is one of the most serious areas of rocky desertification in southwest China provinces, thus our research on this has great practical significance.

  11. Seasonal variability of rocky reef fish assemblages: Detecting functional and structural changes due to fishing effects

    NASA Astrophysics Data System (ADS)

    Henriques, Sofia; Pais, Miguel Pessanha; Costa, Maria José; Cabral, Henrique Nogueira

    2013-05-01

    The present study analyzed the effects of seasonal variation on the stability of fish-based metrics and their capability to detect changes in fish assemblages, which is yet poorly understood despite the general idea that guilds are more resilient to natural variability than species abundances. Three zones subject to different levels of fishing pressure inside the Arrábida Marine Protected Area (MPA) were sampled seasonally. The results showed differences between warm (summer and autumn) and cold (winter and spring) seasons, with the autumn clearly standing out. In general, the values of the metrics density of juveniles, density of invertebrate feeders and density of omnivores increased in warm seasons, which can be attributed to differences in recruitment patterns, spawning migrations and feeding activity among seasons. The density of generalist/opportunistic individuals was sensitive to the effect of fishing, with higher values at zones with the lowest level of protection, while the density of individuals with high commercial value only responded to fishing in the autumn, due to a cumulative result of both juveniles and adults abundances during this season. Overall, this study showed that seasonal variability affects structural and functional features of the fish assemblage and that might influence the detection of changes as a result of anthropogenic pressures. The choice of a specific season, during warm sea conditions after the spawning period (July-October), seems to be more adequate to assess changes on rocky-reef fish assemblages.

  12. Understanding coupled climatic, hydrological, and ecosystem responses to global climate change in the Colorado Rockies

    SciTech Connect

    Stohlgren, T.J.; Baron, J. )

    1993-06-01

    A long-term research program to assess the potential effect of global climate change on the Front Range of the Colorado Rockies, including Rocky Mountain National Park is underway. Specifically, three integrated studies are designed to: (1) project future climate change for the Colorado Rockies using a mesoscale atmospheric model to downscale general circulation model results; (2) develop an understanding of the abiotic and biotic controls on forest distribution and productivity as a basis for assessing potential vegetation change for a range of projected climate scenarios; and (3) evaluate potential responses of hydrologic and aquatic ecosystem processes to climate change at watershed, drainage basin and regional scales. The synthesis of these studies will, in addition, assess the interaction between regional vegetation distribution, mesoscale climate, and hydrology. Our goal is to develop a better understanding of regional climate and hydrologic patterns and of species-environment relationships to determine which species and ecosystem processes are most sensitive to rapid environmental change.

  13. How climate changes in the Rocky Mountains contribute to changes in an alpine lake's phytoplankton community

    NASA Astrophysics Data System (ADS)

    Guido, A. S.; Garland, D.; McKnight, D. M.

    2011-12-01

    It is important to track algae in potable water supplies as they are a factor in the production of dissolved organic matter (DOM) that can result in the formation of disinfection byproducts. Disinfection byproducts have been identified by the Environmental Protection Agency (EPA) as a potential carcinogen and have been linked to reproductive and developmental effects in lab animals. Green Lake 4 is located in the Rocky Mountains and is part of the Silver Lake Watershed which provides 40% of Boulder, CO's potable water supply. In 2002, the Rocky Mountain region had below average precipitation and consequently Green Lake experienced a change in its physical and chemical conditions. As a result of the changes experienced in Green Lake 4, a change in the composition of the phytoplankton community was seen. Along with reduced precipitation levels, this area has also experienced an earlier ice-out date. As part of this research, chemical changes, physical changes, and algae changes in Green Lake 4 will be analyzed. Data from 2007 to 2010 will be analyzed; this study will be looking at both the chemical and physical changes of Green Lake 4 as they relate to the change in ice out of the lake and precipitation in the region.

  14. Ligia italica (Isopoda, Oniscidea) as bioindicator of mercury pollution of marine rocky coasts.

    PubMed

    Longo, Guglielmo; Trovato, Michelanna; Mazzei, Veronica; Ferrante, Margherita; Conti, Gea Oliveri

    2013-01-01

    In this study, we evaluated the possible role of Ligia italica as a bioindicator for the monitoring of heavy metals pollution in the suppralittoral zone of marine rocky coasts. Between 2004 and 2011 specimens of L. italica were collected along the Eastern Sicilian coasts from sites known for their high pollution levels as they are near to an area where in September 2001 a refinery plant discharged into the sea some waste containing Hg. Other specimens were collected from the Vendicari Natural Reserve located about 30 miles from the polluted sites and used as control area. On a consistent number of animals, the concentration in toto of As, Cd, Cr, Hg, Ni, Pb, V, was determined by Atomic Absorption Spectrometry. On other animals, investigations were carried out in order to check for ultrastructural alterations of the hepatopancreas, that is the main metals storage organ in isopods. Results revealed the presence, in the animals collected in 2004 from the polluted sites, of considerable concentrations of Hg and of lower concentrations of other metals such as As, Pb and V. The Hg bioaccumulation resulted in remarkable ultrastructural alterations of the two cellular types (B and S cells) in the epithelium of the hepatopancreas. Surprisingly, a moderate amount of Hg was also found in specimens collected in 2004 from the Vendicari Natural Reserve, proving that the Hg pollution can also spread many miles away. Animals collected from the polluted sites in the following years showed a progressively decreasing Hg content, reaching very low levels in those from the last sampling. Also, the ultrastructural alterations found in the hepatopancreas of the animals from the last sample were quite irrelevant. In conclusion, Ligia italica can represent a good bioindicator and the ultrastructure of the hepatopancreas could be used as ultrastructural biomarker of heavy metals pollution in the supralittoral zones.

  15. Ligia italica (Isopoda, Oniscidea) as Bioindicator of Mercury Pollution of Marine Rocky Coasts

    PubMed Central

    Longo, Guglielmo; Trovato, Michelanna; Mazzei, Veronica; Ferrante, Margherita; Conti, Gea Oliveri

    2013-01-01

    In this study, we evaluated the possible role of Ligia italica as a bioindicator for the monitoring of heavy metals pollution in the suppralittoral zone of marine rocky coasts. Between 2004 and 2011 specimens of L. italica were collected along the Eastern Sicilian coasts from sites known for their high pollution levels as they are near to an area where in September 2001 a refinery plant discharged into the sea some waste containing Hg. Other specimens were collected from the Vendicari Natural Reserve located about 30 miles from the polluted sites and used as control area. On a consistent number of animals, the concentration in toto of As, Cd, Cr, Hg, Ni, Pb, V, was determined by Atomic Absorption Spectrometry. On other animals, investigations were carried out in order to check for ultrastructural alterations of the hepatopancreas, that is the main metals storage organ in isopods. Results revealed the presence, in the animals collected in 2004 from the polluted sites, of considerable concentrations of Hg and of lower concentrations of other metals such as As, Pb and V. The Hg bioaccumulation resulted in remarkable ultrastructural alterations of the two cellular types (B and S cells) in the epithelium of the hepatopancreas. Surprisingly, a moderate amount of Hg was also found in specimens collected in 2004 from the Vendicari Natural Reserve, proving that the Hg pollution can also spread many miles away. Animals collected from the polluted sites in the following years showed a progressively decreasing Hg content, reaching very low levels in those from the last sampling. Also, the ultrastructural alterations found in the hepatopancreas of the animals from the last sample were quite irrelevant. In conclusion, Ligia italica can represent a good bioindicator and the ultrastructure of the hepatopancreas could be used as ultrastructural biomarker of heavy metals pollution in the supralittoral zones. PMID:23472204

  16. Impacts of Climate-Change-Driven Sea Level Rise on Intertidal Rocky Reef Habitats Will Be Variable and Site Specific

    PubMed Central

    Thorner, Jaqueline; Kumar, Lalit; Smith, Stephen D. A.

    2014-01-01

    Intertidal rocky reefs are complex and rich ecosystems that are vulnerable to even the smallest fluctuations in sea level. We modelled habitat loss associated with sea level rise for intertidal rocky reefs using GIS, high-resolution digital imagery, and LIDAR technology at fine-scale resolution (0.1 m per pixel). We used projected sea levels of +0.3 m, +0.5 m and +1.0 m above current Mean Low Tide Level (0.4 m). Habitat loss and changes were analysed for each scenario for five headlands in the Solitary Islands Marine Park (SIMP), Australia. The results indicate that changes to habitat extent will be variable across different shores and will not necessarily result in net loss of area for some habitats. In addition, habitat modification will not follow a regular pattern over the projected sea levels. Two of the headlands included in the study currently have the maximum level of protection within the SIMP. However, these headlands are likely to lose much of the habitat known to support biodiverse assemblages and may not continue to be suitable sanctuaries into the future. The fine-scale approach taken in this study thus provides a protocol not only for modelling habitat modification but also for future proofing conservation measures under a scenario of changing sea levels. PMID:24465915

  17. Impacts of climate-change-driven sea level rise on intertidal rocky reef habitats will be variable and site specific.

    PubMed

    Thorner, Jaqueline; Kumar, Lalit; Smith, Stephen D A

    2014-01-01

    Intertidal rocky reefs are complex and rich ecosystems that are vulnerable to even the smallest fluctuations in sea level. We modelled habitat loss associated with sea level rise for intertidal rocky reefs using GIS, high-resolution digital imagery, and LIDAR technology at fine-scale resolution (0.1 m per pixel). We used projected sea levels of +0.3 m, +0.5 m and +1.0 m above current Mean Low Tide Level (0.4 m). Habitat loss and changes were analysed for each scenario for five headlands in the Solitary Islands Marine Park (SIMP), Australia. The results indicate that changes to habitat extent will be variable across different shores and will not necessarily result in net loss of area for some habitats. In addition, habitat modification will not follow a regular pattern over the projected sea levels. Two of the headlands included in the study currently have the maximum level of protection within the SIMP. However, these headlands are likely to lose much of the habitat known to support biodiverse assemblages and may not continue to be suitable sanctuaries into the future. The fine-scale approach taken in this study thus provides a protocol not only for modelling habitat modification but also for future proofing conservation measures under a scenario of changing sea levels.

  18. Forest Fire Vulnerability in the Northern Rocky Mountains under Climate Change

    NASA Astrophysics Data System (ADS)

    Dalla Vicenza, S. A.; Byrne, J. M.; Letts, M. G.; MacDonald, R. J.

    2011-12-01

    Forest fires are becoming an increasing concern as a result of ongoing and projected climate changes. Rising temperatures, coupled with changes in precipitation patterns and intensities may lead to substantial increases in forest fire vulnerability for many areas, including the Rocky Mountains. Increased soil moisture deficits and longer periods of summer dryness are key controls on forest fires. The main objectives of this research are to assess and quantify the impacts of climate change on forest fire hazard in the northern Rocky Mountains. Ensemble climate scenarios were selected from General Circulation Model (GCM) outputs to represent the possible range of future climates. The Canadian Forest Fire Weather Index System has been integrated with the GENESYS (Generate Earth Systems Science input) hydrometeorological model to assess potential changes in forest fire hazard in the Rocky Mountains. A wind model was developed to estimate daily wind speed variation with elevation. Modelled changes in forest fire hazard are presented for a range of future climate scenarios through 2099 for study regions in the northern Rocky Mountains.

  19. Evolutionary Dynamics in the Southwest Indian Ocean Marine Biodiversity Hotspot: A Perspective from the Rocky Shore Gastropod Genus Nerita

    PubMed Central

    Postaire, Bautisse; Bruggemann, J. Henrich; Magalon, Hélène; Faure, Baptiste

    2014-01-01

    The Southwest Indian Ocean (SWIO) is a striking marine biodiversity hotspot. Coral reefs in this region host a high proportion of endemics compared to total species richness and they are particularly threatened by human activities. The island archipelagos with their diverse marine habitats constitute a natural laboratory for studying diversification processes. Rocky shores in the SWIO region have remained understudied. This habitat presents a high diversity of molluscs, in particular gastropods. To explore the role of climatic and geological factors in lineage diversification within the genus Nerita, we constructed a new phylogeny with an associated chronogram from two mitochondrial genes [cytochrome oxidase sub-unit 1 and 16S rRNA], combining previously published and new data from eight species sampled throughout the region. All species from the SWIO originated less than 20 Ma ago, their closest extant relatives living in the Indo-Australian Archipelago (IAA). Furthermore, the SWIO clades within species with Indo-Pacific distribution ranges are quite recent, less than 5 Ma. These results suggest that the regional diversification of Nerita is closely linked to tectonic events in the SWIO region. The Reunion mantle plume head reached Earth’s surface 67 Ma and has been stable and active since then, generating island archipelagos, some of which are partly below sea level today. Since the Miocene, sea-level fluctuations have intermittently created new rocky shore habitats. These represent ephemeral stepping-stones, which have likely facilitated repeated colonization by intertidal gastropods, like Nerita populations from the IAA, leading to allopatric speciation. This highlights the importance of taking into account past climatic and geological factors when studying diversification of highly dispersive tropical marine species. It also underlines the unique history of the marine biodiversity of the SWIO region. PMID:24736639

  20. The Response of Vegetation Zonation in Rocky Mountain Ecotones to Climate Change

    NASA Astrophysics Data System (ADS)

    Foster, A.; Shuman, J. K.; Shugart, H. H., Jr.

    2014-12-01

    Mean annual temperatures in the western United States have increased in the last few decades, and during the 21st century, it is predicted that this warming trend will continue. This change in climate may create shifts in the optimal ranges of vegetation within the Rocky Mountains, requiring species migration. For a species at the top of a mountain there may be little room for upward migration. These forests are a crucial part of the US's carbon budget, thus it is important to analyze how climate change will affect the zonation and species composition of vegetation in Rocky Mountain landscapes. UVAFME is an individual-based gap model that simulates biomass and species composition of a forest. Originally developed for northeast China and applied across all of Russia, this model has accurately simulated diverse forests in a range of climates, as well as the response of these forests to climate change. UVAFME is first calibrated to several sites along the Colorado and Wyoming Rocky Mountains using species, soil, and climate data from the US Forest Service. The initial model output of biomass and species composition is tested against forest inventory data and expected forest type ecotone along an elevational gradient. The model is then run with a linear increase in temperature of 3°C over 200 years, corresponding to the A1B IPPC climate scenario. These results are compared to current forest inventory data and to model runs without climate change. We project that with climate change species ranges will shift up the mountain, leading to an increase in the deciduous species Populus tremuloides, and a decrease in coniferous species at high elevations. These results are an important step in evaluating the response of Rocky Mountain vegetation to climate change and will help predict the future of these crucial ecosystems.

  1. Rocky Chairland: Educating a Changing Health Care Workforce.

    ERIC Educational Resources Information Center

    Connolly, Charlene

    Recognizing the need to be proactive in redefining the role of nursing and allied health practitioners at the associate degree level and transforming curricula to meet the changing demands of health care, the Division of Health Technologies at Northern Virginia Community College, in partnership with local community agencies, implemented the Mobile…

  2. Improving climate change knowledge in the Northern Rocky Mountains, USA.

    NASA Astrophysics Data System (ADS)

    Fagre, D. B.

    2007-12-01

    There are many challenges to involving authentic scientists in classroom and media communications and one is the willingness of scientists to participate. The reticence of scientists to be involved has various roots but one solution is to partner with individuals and institutions experienced in outreach. At Glacier National Park, USGS scientists have worked closely with the Crown of the Continent Research and Learning Center, part of a U.S. National Park Service initiative to improve science-based decisionmaking. The controversial topic of global warming has been embraced as a science theme and research results have been crafted into compact messages for various audiences. The interpretive staff developed a core curriculum on climate change and receive annual training directly from scientists on the most recent research. The interpretive staff interact directly while leading hikes, giving campfire talks, and at visitor centers with many of the 2.2 million visitors each year who are generally more receptive while on vacation than during busy daily lives. Wayside exhibits along the Going-to- the-Sun Road explain climate change and melting glaciers, free brochures describe other aspects of climate change, electronic kiosks have short movies, and a newsletter handout at the entrance station has a science feature in it. To aid this effort, scientists have worked harder at developing compelling graphics, creating animations, serving more media-savvy materials on websites, and providing CDs with scientific data and backup materials. A website developed for serving historic and current photographs of glaciers has been so popular with the media that it has received as many as 8,000 hits in a day. Active participation by scientists in network newscasts and documentaries may involve up to 2 days of hiking TV crews into the backcountry and much effort in reviewing scripts and confirming information. This is essential to keeping credible information going to the public despite

  3. Area change of glaciers in the Canadian Rocky Mountains, 1919 to 2006

    NASA Astrophysics Data System (ADS)

    Tennant, C.; Menounos, B.; Wheate, R.; Clague, J. J.

    2012-12-01

    Glaciers in the Canadian Rocky Mountains constitute an important freshwater resource. To enhance our understanding of the influence climate and local topography have on glacier area, large numbers of glaciers of different sizes and attributes need to be monitored over periods of many decades. We used Interprovincial Boundary Commission Survey (IBCS) maps of the Alberta-British Columbia (BC) border (1903-1924), BC Terrain Resource Information Management (TRIM) data (1982-1987), and Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM+) imagery (2000-2002 and 2006) to document planimetric changes in glacier cover in the central and southern Canadian Rocky Mountains between 1919 and 2006. Over this period, glacier cover in the study area decreased by 590 ± 70 km2 (40 ± 5%), 17 of 523 glaciers disappeared and 124 glaciers fragmented into multiple ice masses. Glaciers smaller than 1.0 km2 experienced the greatest relative area loss (64 ± 8%), and relative area loss is more variable with small glaciers, suggesting that the local topographic setting controls the response of these glaciers to climate change. Small glaciers with low slopes, low mean/median elevations, south to west aspects, and high insolation experienced the largest reduction in area. Similar rates of area change characterize the periods 1919-1985 and 1985-2001; -6.3 ± 0.6 km2 yr-1 (-0.4 ± 0.1% yr-1) and -5.0 ± 0.5 km2 yr-1 (-0.5 ± 0.1% yr-1), respectively. The rate of area loss, however, increased over the period 2001-2006; -19.3 ± 2.4 km2 yr-1 (-2.0 ± 0.2% yr-1). Applying size class-specific scaling factors, we estimate a total reduction in glacier cover in the central and southern Canadian Rocky Mountains for the period 1919-2006 of 750 km2 (30%).

  4. Development of monitoring protocols to detect change in rocky intertidal communities of Glacier Bay National Park and Preserve

    USGS Publications Warehouse

    Irvine, Gail V.

    2010-01-01

    Glacier Bay National Park and Preserve in southeastern Alaska includes extensive coastlines representing a major proportion of all coastlines held by the National Park Service. The marine plants and invertebrates that occupy intertidal shores form highly productive communities that are ecologically important to a number of vertebrate and invertebrate consumers and that are vulnerable to human disturbances. To better understand these communities and their sensitivity, it is important to obtain information on species abundances over space and time. During field studies from 1997 to 2001, I investigated probability-based rocky intertidal monitoring designs that allow inference of results to similar habitat within the bay and that reduce bias. Aerial surveys of a subset of intertidal habitat indicated that the original target habitat of bedrock-dominated sites with slope less than or equal to 30 degrees was rare. This finding illustrated the value of probability-based surveys and led to a shift in the target habitat type to more mixed rocky habitat with steeper slopes. Subsequently, I investigated different sampling methods and strategies for their relative power to detect changes in the abundances of the predominant sessile intertidal taxa: barnacles -Balanomorpha, the mussel Mytilus trossulus and the rockweed Fucus distichus subsp. evanescens. I found that lower-intensity sampling of 25 randomly selected sites (= coarse-grained sampling) provided a greater ability to detect changes in the abundances of these taxa than did more intensive sampling of 6 sites (= fine-grained sampling). Because of its greater power, the coarse-grained sampling scheme was adopted in subsequent years. This report provides detailed analyses of the 4 years of data and evaluates the relative effect of different sampling attributes and management-set parameters on the ability of the sampling to detect changes in the abundances of these taxa. The intent was to provide managers with information

  5. Recruitment dynamics in complex life cycles. [of organisms living in marine rocky zone

    NASA Technical Reports Server (NTRS)

    Roughgarden, Jonathan; Possingham, Hugh; Gaines, Steven

    1988-01-01

    Factors affecting marine population fluctuations are discussed with particular attention given to a common barnacle species of the Pacific coast of North America. It is shown how models combining larval circulation with adult interactions can potentially forecast population fluctuations. These findings demonstrate how processes in different ecological habitats are coupled.

  6. Long-term changes in rocky intertidal macrobenthos during the five years after the Hebei Spirit oil spill, Taean, Korea

    NASA Astrophysics Data System (ADS)

    Jung, Yun-Hwan; Park, Henug-Sik; Yoon, Kon-Tak; Kim, Hyung-June; Shim, Won-Joon

    2017-03-01

    The Hebei Spirit oil spill reached the west coast of Taean County, Korea, on December 7, 2007. At that time, this was the largest oil spill that had occurred in the country. The incident devastated local marine ecosystems. In this study, we examined changes in these ecosystems and the recovery pattern on impacted rocky shores. Macrobenthos monitoring of polluted and control sites was performed seasonally from January 2008 through October 2013. At polluted sites, ecological indices increased gradually from 2009, thereby providing evidence of recovery. However, the mean density of macrobenthos was still less than 50% of the level at the control site, indicating that the ecological status of the polluted sites has still not recovered to that which prevailed before the oil spill. Although densities of the most dominant species were higher in the control site than in polluted sites, the densities of Lottia spp. and Odostomia aomori were higher in polluted sites. These two taxa were found in lower numbers at the control site, where they were out-competed by Chthamalus challengeri. Nonmetric multidimensional scaling ordination divided the macrobenthic community structure into three clusters according to differences in the abundance of dominant species over the 6 years after the oil spill. An ANOSIM test detected significant differences between the polluted and control sites. Consistent long-term differences indicate that complete recovery had not occurred during the duration of our study.

  7. Long-term changes in rocky intertidal macrobenthos during the five years after the Hebei Spirit oil spill, Taean, Korea

    NASA Astrophysics Data System (ADS)

    Jung, Yun-Hwan; Park, Henug-Sik; Yoon, Kon-Tak; Kim, Hyung-June; Shim, Won-Joon

    2017-02-01

    The Hebei Spirit oil spill reached the west coast of Taean County, Korea, on December 7, 2007. At that time, this was the largest oil spill that had occurred in the country. The incident devastated local marine ecosystems. In this study, we examined changes in these ecosystems and the recovery pattern on impacted rocky shores. Macrobenthos monitoring of polluted and control sites was performed seasonally from January 2008 through October 2013. At polluted sites, ecological indices increased gradually from 2009, thereby providing evidence of recovery. However, the mean density of macrobenthos was still less than 50% of the level at the control site, indicating that the ecological status of the polluted sites has still not recovered to that which prevailed before the oil spill. Although densities of the most dominant species were higher in the control site than in polluted sites, the densities of Lottia spp. and Odostomia aomori were higher in polluted sites. These two taxa were found in lower numbers at the control site, where they were out-competed by Chthamalus challengeri. Nonmetric multidimensional scaling ordination divided the macrobenthic community structure into three clusters according to differences in the abundance of dominant species over the 6 years after the oil spill. An ANOSIM test detected significant differences between the polluted and control sites. Consistent long-term differences indicate that complete recovery had not occurred during the duration of our study.

  8. Marine debris: Implications for conservation of rocky reefs in Manabi, Ecuador (Se Pacific Coast).

    PubMed

    Figueroa-Pico, Juan; Valle, David Mero-Del; Castillo-Ruperti, Ricardo; Macías-Mayorga, Dayanara

    2016-08-15

    Marine debris (MD) pollution is a problem of global concern because of its impact on marine ecosystems. The current extent of this problem and its implications concerning reef conservation are unknown in Ecuador. The composition and distribution of submerged MD was assessed on two reefs using underwater surveys of geomorphological areas: crest, slope and bottom. MD items were classified according to source and use. Plastic-derived debris represents >90% of total MD found on the reefs, principally composed by plastic containers and nets. 63% of the MD was associated to fishing activities. The composition showed differences between sites and geomorphological areas, monofilament nets were found on the crests, multifilament lines on the slopes and plastic containers on the bottom. MD disposal might be a result of the influx of visitors and fishing activities. Distribution is related to bottom type, level of boating/fishing activity and benthic features.

  9. Declining summer flows of Rocky Mountain rivers: Changing seasonal hydrology and probable impacts on floodplain forests

    NASA Astrophysics Data System (ADS)

    Rood, Stewart B.; Pan, Jason; Gill, Karen M.; Franks, Carmen G.; Samuelson, Glenda M.; Shepherd, Anita

    2008-02-01

    SummaryIn analyzing hydrologic consequences of climate change, we previously found declining annual discharges of rivers that drain the hydrographic apex of North America, the Rocky Mountain headwaters region for adjacent streams flowing to the Arctic, Atlantic and Pacific oceans. In this study we investigated historic changes in seasonal patterns of streamflows, by comparing mean monthly flows and analyzing cumulative hydrographs over the periods of record of about a century. We tested predictions of change due to winter and spring warming that would increase the proportion of rain versus snow, and alter snow accumulation and melt. We analyzed records from 14 free-flowing, snow-melt dominated rivers that drained relatively pristine parks and protected areas, thus avoiding the effects of river damming, flow regulation, or watershed development. The collective results indicated that: (1) winter flows (especially March) were often slightly increased, (2) spring run-off and (3) peak flows occurred earlier, and most substantially, (4) summer and early autumn flows (July-October) were considerably reduced. The greatest changes were observed for the rivers draining the east-slope of the Rocky Mountains toward the northern prairies and Hudson Bay, with late summer flow decline rates of about 0.2%/year. This would have considerable ecological impact since this is the warm and dry period when evaporative demand is maximal and reduced instream flows would reduce riparian groundwater recharge, imposing drought stress on floodplain forests. In combination with the decline in annual discharge, earlier peaks and reduced summer flows would provide chronic stress on riparian cottonwoods and willows and especially restrict seedling recruitment. We predict a loss of floodplain forests along some river reaches, the narrowing of forest bands along other reaches, and increased vulnerability of these ecosystems to other impacts including livestock grazing, encroachment of upland

  10. Adapting natural resource management to climate change: The South Central Oregon and Northern Rockies Adaptation Partnerships

    NASA Astrophysics Data System (ADS)

    Halofsky, J.; Peterson, D. L.

    2015-12-01

    Concrete ways to adapt to climate change are needed to help natural resource managers take the first steps to incorporate climate change into management and take advantage of opportunities to balance the negative effects of climate change. We recently initiated two science-management climate change adaptation partnerships, one with three national forests and one national park in south central Oregon, and the other with 16 national forests, three national parks and other stakeholders in the northern Rockies region. Goals of both partnerships were to: (1) synthesize published information and data to assess the exposure, sensitivity, and adaptive capacity of key resource areas, including water use, infrastructure, fisheries, and vegetation and disturbance; (2) develop science-based adaptation strategies and tactics that will help to mitigate the negative effects of climate change and assist the transition of biological systems and management to a warmer climate; (3) ensure adaptation strategies and tactics are incorporated into relevant planning documents; and (4) foster an enduring partnership to facilitate ongoing dialogue and activities related to climate change in the partnerships regions. After an initial vulnerability assessment by agency and university scientists and local resource specialists, adaptation strategies and tactics were developed in a series of scientist-manager workshops. The final vulnerability assessments and adaptation actions are incorporated in technical reports. The partnerships produced concrete adaptation options for national forest and other natural resource managers and illustrated the utility of place-based vulnerability assessments and scientist-manager workshops in adapting to climate change.

  11. Adapting Natural Resource Management to Climate Change: The Blue Mountains and Northern Rockies Adaptation Partnerships

    NASA Astrophysics Data System (ADS)

    Halofsky, J.; Peterson, D. L.

    2014-12-01

    Concrete ways to adapt to climate change are needed to help natural resource managers take the first steps to incorporate climate change into management and take advantage of opportunities to balance the negative effects of climate change. We recently initiated two science-management climate change adaptation partnerships, one with three national forests and other key stakeholders in the Blue Mountains region of northeastern Oregon, and the other with 16 national forests, three national parks and other stakeholders in the northern Rockies region. Goals of both partnerships were to: (1) synthesize published information and data to assess the exposure, sensitivity, and adaptive capacity of key resource areas, including water use, infrastructure, fisheries, and vegetation and disturbance; (2) develop science-based adaptation strategies and tactics that will help to mitigate the negative effects of climate change and assist the transition of biological systems and management to a warmer climate; (3) ensure adaptation strategies and tactics are incorporated into relevant planning documents; and (4) foster an enduring partnership to facilitate ongoing dialogue and activities related to climate change in the partnerships regions. After an initial vulnerability assessment by agency and university scientists and local resource specialists, adaptation strategies and tactics were developed in a series of scientist-manager workshops. The final vulnerability assessments and adaptation actions are incorporated in technical reports. The partnerships produced concrete adaptation options for national forest and other natural resource managers and illustrated the utility of place-based vulnerability assessments and scientist-manager workshops in adapting to climate change.

  12. Longshore-drift dispersed, storm-generated cross-stratified sandstone from some Cretaceous shallow marine strata, Rocky Mountain region

    SciTech Connect

    Gustason, E.R. )

    1990-05-01

    Most Cretaceous shallow marine strata of the Rocky Mountain region are characterized by asymmetrical upward-coarsening and upward-thickening sequences. The strata typically contain similar lithofacies (i.e., normally graded planar parallel laminated claystone, siltstone, and sandstone; hummocky cross-stratified sandstone; symmetrical and asymmetrical ripple cross-lamination; and trough and planar tublar cross-stratified sandstone) and display an upward increase in the thickness and frequency of sharp-based sandstone beds that grade into amalgamated cross-stratified sandstone. Most workers agree that sharp-based sandstone beds and hummocky cross-stratified sandstone are storm generated. However, the origin of trough and planar tabular cross-stratified sandstone is controversial. Most workers interpret these sedimentary structures as deposited from either storm-generated traction currents or combined flow currents on the shelf, tide-generated traction currents, or tidally dispersed, storm-generated suspension clouds. Detailed analysis of three-dimensional outcrops has revealed several significant features of these sedimentary structures that indicate they may have been deposited by longshore drift dispersed, storm-generated suspension clouds. Sets of trough and planar cross-stratified sandstone form medium-scale discontinuous, irregularly shaped sand bodies, bound by erosional surfaces and composed of unidirectional dip-oriented cross strata. Individual cross stratum commonly have a sigmoidal shape, are bound by either reactivation surfaces or mudstone drapes, and contain normally graded concordant laminae. Top-set laminae, are truncated by the upper set boundary, whereas bottom-set laminae, become asymptotic to the lower set boundary and commonly are reworked and overlain by wave generated, ripple cross-lamination or mudstone drapes.

  13. Marine viruses and global climate change.

    PubMed

    Danovaro, Roberto; Corinaldesi, Cinzia; Dell'anno, Antonio; Fuhrman, Jed A; Middelburg, Jack J; Noble, Rachel T; Suttle, Curtis A

    2011-11-01

    Sea-surface warming, sea-ice melting and related freshening, changes in circulation and mixing regimes, and ocean acidification induced by the present climate changes are modifying marine ecosystem structure and function and have the potential to alter the cycling of carbon and nutrients in surface oceans. Changing climate has direct and indirect consequences on marine viruses, including cascading effects on biogeochemical cycles, food webs, and the metabolic balance of the ocean. We discuss here a range of case studies of climate change and the potential consequences on virus function, viral assemblages and virus-host interactions. In turn, marine viruses influence directly and indirectly biogeochemical cycles, carbon sequestration capacity of the oceans and the gas exchange between the ocean surface and the atmosphere. We cannot yet predict whether the viruses will exacerbate or attenuate the magnitude of climate changes on marine ecosystems, but we provide evidence that marine viruses interact actively with the present climate change and are a key biotic component that is able to influence the oceans' feedback on climate change. Long-term and wide spatial-scale studies, and improved knowledge of host-virus dynamics in the world's oceans will permit the incorporation of the viral component into future ocean climate models and increase the accuracy of the predictions of the climate change impacts on the function of the oceans.

  14. Distributional changes and range predictions of downy brome (Bromus tectorum) in Rocky Mountain National Park

    USGS Publications Warehouse

    Bromberg, J.E.; Kumar, S.; Brown, C.S.; Stohlgren, T.J.

    2011-01-01

    Downy brome (Bromus tectorum L.), an invasive winter annual grass, may be increasing in extent and abundance at high elevations in the western United States. This would pose a great threat to high-elevation plant communities and resources. However, data to track this species in high-elevation environments are limited. To address changes in the distribution and abundance of downy brome and the factors most associated with its occurrence, we used field sampling and statistical methods, and niche modeling. In 2007, we resampled plots from two vegetation surveys in Rocky Mountain National Park for presence and cover of downy brome. One survey was established in 1993 and had been resampled in 1999. The other survey was established in 1996 and had not been resampled until our study. Although not all comparisons between years demonstrated significant changes in downy brome abundance, its mean cover increased nearly fivefold from 1993 (0.7%) to 2007 (3.6%) in one of the two vegetation surveys (P = 0.06). Although the average cover of downy brome within the second survey appeared to be increasing from 1996 to 2007, this slight change from 0.5% to 1.2% was not statistically significant (P = 0.24). Downy brome was present in 50% more plots in 1999 than in 1993 (P = 0.02) in the first survey. In the second survey, downy brome was present in 30% more plots in 2007 than in 1996 (P = 0.08). Maxent, a species-environmental matching model, was generally able to predict occurrences of downy brome, as new locations were in the ranges predicted by earlier generated models. The model found that distance to roads, elevation, and vegetation community influenced the predictions most. The strong response of downy brome to interannual environmental variability makes detecting change challenging, especially with small sample sizes. However, our results suggest that the area in which downy brome occurs is likely increasing in Rocky Mountain National Park through increased frequency and cover

  15. Diagnosis of Hydrological Resiliency and Functional Change in a Canadian Rockies Mountain Basin

    NASA Astrophysics Data System (ADS)

    Harder, P.; Pomeroy, J. W.; Siemens, E.; Fang, X.

    2015-12-01

    A well-instrumented headwater basin in the Canadian Rockies, Marmot Creek Research Basin, has experienced substantial warming at a range of elevations with evidence of hydrological functional change, but there has been no change observed in the streamflow regime over the last 50 years. Despite observations of increased air temperature of up to 4 oC in winter, concentration of precipitation into multiple day events in the spring, decreased peak snow accumulation at lower elevations by 50%, and decreased (increased) low (high) elevation groundwater storage; there are no trends in streamflow timing, peak or seasonal volumes since records began in 1962. This suggests a remarkable resilience in runoff generation to changing temperature and precipitation regime in a cold regions basin. To diagnose possible reasons for this resilience the Cold Regions Hydrological Model (CRHM) simulated the basin hydrological processes and response over two periods that had excellent driving meteorology; 1969-1987 and 2006-2013. CRHM calculates all of the relevant hydrological processes including blowing snow redistribution, intercepted snow and rain loss, sublimation, snowmelt, evapotranspiration, infiltration into frozen and unfrozen soils, overland flow, interflow in organic soils, sub-surface runoff in mineral soils, soil water redistribution and groundwater flow. Model results show that compared to the first period, increases in annual, basin-averaged fluxes occurred in the latter period for rainfall (37%), snowfall (20%), snowmelt (30%), evapotranspiration (23%), and sublimation (42%), but no significant trend in runoff developed between the two periods. Snowmelt, sublimation and runoff increases were primarily at high elevations and sometimes reversed at lower elevations, whilst evapotranspiration and rainfall increases were at all elevations. This suggests that there are compensatory, altitude dependent increases in evaporative losses from sublimation and evapotranspiration that

  16. Phenological and ecological consequences of changes in winter snowpack in the Colorado Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Inouye, D. W.; McKinney, A. M.

    2012-12-01

    The date the snowpack disappears in spring is an important seasonal event at high altitudes because it determines the beginning of the growing season, which in turn influences the phenology of plant growth and flowering, and thus the availability of these resources for animal consumers. At our study site at 2,900m in the Colorado Rocky Mountains, the Rocky Mountain Biological Laboratory, snowmelt now averages two weeks earlier than in 1975. Earlier snowmelt results from a combination of lower snowfall (38 cm less since 1975), dust storms (increasing in frequency, which reduces the snowpack albedo), and warmer spring temperatures (April minimum temperature has increased 3.1°C since 1973; 2012 April mean temperature was 3.4°C above the 38-year mean). There is also a trend of increasing annual precipitation falling as rain instead of snow. We have monitored flowering phenology and abundance for about 100 species of plants in permanent plots since 1973, and use this record to look at how the change in timing of snowmelt has affected flowering. There is significant variation among years in flowering phenology (e.g., about six weeks difference between 2011 and 2012), with a mid-season decline in flowering abundance becoming apparent as the growing season starts earlier. The date of the last hard frost has not been changing in concert with the earlier growing season, with the consequence that many species now have flower buds developed that are then damaged or killed by frost. In 2012, snowmelt date was 23 April, and frost events on 27 May (-11.7°C) and 11 June (-5.6°C) did significant damage to vegetation of some species and to flower buds of many species. For example, flower abundance of the aspen sunflower Helianthella quinquenervis was 0.002% of 2011's flowering. In the absence of seed production, the demography of some plant species is likely being affected. Some animal species are also being affected by the changes in length and temperature of winter. New

  17. Water quality changes as a result of coalbed methane development in a Rocky mountain watershed

    SciTech Connect

    Wang, X.; Melesse, A.M.; McClain, M.E.; Yang, W.

    2007-12-15

    Coalbed methane (CBM) development raises serious environmental concerns. In response, concerted efforts have been made to collect chemistry, salinity, and sodicity data on CBM produced water. However, little information on changes of stream water quality resulting from directly and/or indirectly received CBM produced water is available in the literature. The objective of this study was to examine changes in stream water quality, particularly sodicity and salinity, due to CBM development in the Powder River watershed, which is located in the Rocky Mountain Region and traverses the states of Wyoming and Montana. To this end, a retrospective analysis of water quality trends and patterns was conducted using data collected from as early as 1946 up to and including 2002 at four U.S. Geological Survey gauging stations along the Powder River. Trend analysis was conducted using linear regression and Seasonal Kendall tests, whereas, Tukey's test for multiple comparisons was used to detect changes in the spatial pattern. The results indicated that the CBM development adversely affected the water quality in the Powder River. First, the development elevated the stream sodicity, as indicated by a significant increase trend of the sodium adsorption ratio. Second, the development tended to shrink the water quality differences among the three downstream stations but to widen the differences between these stations and the farthest upstream station. In contrast, the development had only a minor influence on stream salinity. Hence, the CBM development is likely an important factor that can be managed to lower the stream sodicity. The management may need to take into account that the effects of the CBMdevelopment were different from one location to another along the Powder River.

  18. Simulating long-term landcover change and forest hydrology dynamics in a Rocky Mountain watershed

    NASA Astrophysics Data System (ADS)

    Ahl, R. S.; Zuuring, H. R.

    2008-05-01

    Snow is the dominant source of water in the Rocky Mountains. In forested watersheds, patterns of snow accumulation, melt and evapotranspiration are strongly influenced by canopy and other vegetation characteristics. Changes in the extent, composition, and configuration of the forest canopy over time due to succession or disturbance processes can lead to measurable changes in streamflow and water yield. Removal of forest cover generally increases streamflow due to reduced canopy interception and evapotranspiration. Water, yield increases and advanced peak discharge are attributed to increased snow accumulation, and enhanced melt rates in forest openings. Because knowledge of long-term watershed-level streamflow responses to landcover dynamics is limited by relatively short-term gauge data, a modeling approach that takes advantage of existing data and combines vegetation and hydrologic simulation systems to evaluate these interactions is presented. Time-series vegetation changes were simulated with the SIMPPLLE (Simulating Patterns and Processes at Landscape ScaLEs), and integrated into hydrologic simulations performed with SWAT (Soil and Water Assessment Tool). Results suggest that both vegetation and hydrologic characteristics of the research watershed are at the limits of their estimated natural ranges. Although simulated species composition remained fairly stable over time, the size and connectivity of current landcover patches are at the upper end of their estimated temporal distribution. The large proportion and continuous extent of forest cover associated with current conditions coincide with water yield, peak discharge rates, and flow variability that are at the low end of their modeled distributions. The integrated modeling approach described herein should be applicable in other ecosystems given knowledge of biophysical interactions and availability of appropriate data. By gaining an understanding of the possible range of variability due to natural

  19. Hypoxia in the changing marine environment

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Cowie, G.; Naqvi, S. W. A.

    2013-03-01

    The predicted future of the global marine environment, as a combined result of forcing due to climate change (e.g. warming and acidification) and other anthropogenic perturbation (e.g. eutrophication), presents a challenge to the sustainability of ecosystems from tropics to high latitudes. Among the various associated phenomena of ecosystem deterioration, hypoxia can cause serious problems in coastal areas as well as oxygen minimum zones in the open ocean (Diaz and Rosenberg 2008 Science 321 926-9, Stramma et al 2008 Science 320 655-8). The negative impacts of hypoxia include changes in populations of marine organisms, such as large-scale mortality and behavioral responses, as well as variations of species distributions, biodiversity, physiological stress, and other sub-lethal effects (e.g. growth and reproduction). Social and economic activities that are related to services provided by the marine ecosystems, such as tourism and fisheries, can be negatively affected by the aesthetic outcomes as well as perceived or real impacts on seafood quality (STAP 2011 (Washington, DC: Global Environment Facility) p 88). Moreover, low oxygen concentration in marine waters can have considerable feedbacks to other compartments of the Earth system, like the emission of greenhouse gases to the atmosphere, and can affect the global biogeochemical cycles of nutrients and trace elements. It is of critical importance to prediction and adaptation strategies that the key processes of hypoxia in marine environments be precisely determined and understood (cf Zhang et al 2010 Biogeosciences 7 1-24).

  20. Variation of Vegetation Ecological Water Consumption and Its Response to Vegetation Coverage Changes in the Rocky Desertification Areas in South China

    PubMed Central

    Zhou, Jinxing; Guo, Hongyan; Cui, Ming; Liu, Yuguo; Ning, Like; Tang, Fukai

    2016-01-01

    Over the past several decades, rocky desertification has led to severe ecological problems in karst areas in South China. After a rocky desertification treatment project was completed, the vegetation coverage changed greatly and, consequently, increased the ecology water consumption (approximately equal to the actual evapotranspiration) of the regional vegetation. Thus, it intensified the regional water stresses. This study explored the changes in the actual evapotranspiration (ETa) response to the vegetation coverage changes in the rocky desertification areas in South China based on the precipitation (P), potential evapotranspiration (ETp) and NDVI (the normalized difference vegetation index) datasets. The revised Bagrov model was used to simulate the actual evapotranspiration changes with the supposed increasing NDVI. The results indicated that the average NDVI value was lower when the rocky desertification was more severe. The ETa, evapotranspiration efficiency (ETa/ETp) and potential humidity (P/ETp) generally increased with the increasing NDVI. The sensitivity of the ETa response to vegetation coverage changes varied due to different precipitation conditions and different rocky desertification severities. The ETa was more sensitive under drought conditions. When a drought occurred, the ETa exhibited an average increase of 40~60 mm with the NDVI increasing of 0.1 in the rocky desertification areas. Among the 5 different severity categories of rocky desertification, the ETa values’ responses to NDVI changes were less sensitive in the severe rocky desertification areas but more sensitive in the extremely and potential rocky desertification areas. For example, with the NDVI increasing of 0.025, 0.05, 0.075, and 0.1, the corresponding ETa changes increased by an average of 2.64 mm, 10.62 mm, 19.19 mm, and 27.58 mm, respectively, in severe rocky desertification areas but by 4.94 mm, 14.99 mm, 26.80, and 37.13 mm, respectively, in extremely severe rocky

  1. Variation of Vegetation Ecological Water Consumption and Its Response to Vegetation Coverage Changes in the Rocky Desertification Areas in South China.

    PubMed

    Wan, Long; Tong, Jing; Zhou, Jinxing; Guo, Hongyan; Cui, Ming; Liu, Yuguo; Ning, Like; Tang, Fukai

    2016-01-01

    Over the past several decades, rocky desertification has led to severe ecological problems in karst areas in South China. After a rocky desertification treatment project was completed, the vegetation coverage changed greatly and, consequently, increased the ecology water consumption (approximately equal to the actual evapotranspiration) of the regional vegetation. Thus, it intensified the regional water stresses. This study explored the changes in the actual evapotranspiration (ETa) response to the vegetation coverage changes in the rocky desertification areas in South China based on the precipitation (P), potential evapotranspiration (ETp) and NDVI (the normalized difference vegetation index) datasets. The revised Bagrov model was used to simulate the actual evapotranspiration changes with the supposed increasing NDVI. The results indicated that the average NDVI value was lower when the rocky desertification was more severe. The ETa, evapotranspiration efficiency (ETa/ETp) and potential humidity (P/ETp) generally increased with the increasing NDVI. The sensitivity of the ETa response to vegetation coverage changes varied due to different precipitation conditions and different rocky desertification severities. The ETa was more sensitive under drought conditions. When a drought occurred, the ETa exhibited an average increase of 40~60 mm with the NDVI increasing of 0.1 in the rocky desertification areas. Among the 5 different severity categories of rocky desertification, the ETa values' responses to NDVI changes were less sensitive in the severe rocky desertification areas but more sensitive in the extremely and potential rocky desertification areas. For example, with the NDVI increasing of 0.025, 0.05, 0.075, and 0.1, the corresponding ETa changes increased by an average of 2.64 mm, 10.62 mm, 19.19 mm, and 27.58 mm, respectively, in severe rocky desertification areas but by 4.94 mm, 14.99 mm, 26.80, and 37.13 mm, respectively, in extremely severe rocky

  2. Assessment of climate change and freshwater ecosystems of the Rocky Mountains, USA and Canada

    USGS Publications Warehouse

    Hauer, F. Richard; Baron, J.S.; Campbell, D.H.; Fausch, K.D.; Hostetler, S.W.; Leavesley, G.H.; Leavitt, P.R.; McKnight, Diane M.; Stanford, J.A.

    1997-01-01

    The Rocky Mountains in the USA and Canada encompass the interior cordillera of western North America, from the southern Yukon to northern New Mexico. Annual weather patterns are cold in winter and mild in summer. Precipitation has high seasonal and interannual variation and may differ by an order of magnitude between geographically close locales, depending on slope, aspect and local climatic and orographic conditions. The region's hydrology is characterized by the accumulation of winter snow, spring snowmelt and autumnal baseflows. During the 2-3-month 'spring runoff' period, rivers frequently discharge >70% of their annual water budget and have instantaneous discharges 10-100 times mean low flow. Complex weather patterns characterized by high spatial and temporal variability make predictions of future conditions tenuous. However, general patterns are identifiable; northern and western portions of the region are dominated by maritime weather patterns from the North Pacific, central areas and eastern slopes are dominated by continental air masses and southern portions receive seasonally variable atmospheric circulation from the Pacific and the Gulf of Mexico. Significant interannual variations occur in these general patterns, possibly related to ENSO (El Nin??o-Southern Oscillation) forcing. Changes in precipitation and temperature regimes or patterns have significant potential effects on the distribution and abundance of plants and animals. For example, elevation of the timber-line is principally a function of temperature. Palaeolimnological investigations have shown significant shifts in phyto- and zoo-plankton populations as alpine lakes shift between being above or below the timber-line. Likewise, streamside vegetation has a significant effect on stream ecosystem structure and function. Changes in stream temperature regimes result in significant changes in community composition as a consequence of bioenergetic factors. Stenothermic species could be extirpated as

  3. Assessment of Climate Change and Freshwater Ecosystems of the Rocky Mountains, USA and Canada

    NASA Astrophysics Data System (ADS)

    Hauer, F. Richard; Baron, Jill S.; Campbell, Donald H.; Fausch, Kurt D.; Hostetler, Steve W.; Leavesley, George H.; Leavitt, Peter R.; McKnight, Diane M.; Stanford, Jack A.

    1997-06-01

    The Rocky Mountains in the USA and Canada encompass the interior cordillera of western North America, from the southern Yukon to northern New Mexico. Annual weather patterns are cold in winter and mild in summer. Precipitation has high seasonal and interannual variation and may differ by an order of magnitude between geographically close locales, depending on slope, aspect and local climatic and orographic conditions. The region's hydrology is characterized by the accumulation of winter snow, spring snowmelt and autumnal baseflows. During the 2-3-month spring runoff period, rivers frequently discharge > 70% of their annual water budget and have instantaneous discharges 10-100 times mean low flow.Complex weather patterns characterized by high spatial and temporal variability make predictions of future conditions tenuous. However, general patterns are identifiable; northern and western portions of the region are dominated by maritime weather patterns from the North Pacific, central areas and eastern slopes are dominated by continental air masses and southern portions receive seasonally variable atmospheric circulation from the Pacific and the Gulf of Mexico. Significant interannual variations occur in these general patterns, possibly related to ENSO (El Niño-Southern Oscillation) forcing.Changes in precipitation and temperature regimes or patterns have significant potential effects on the distribution and abundance of plants and animals. For example, elevation of the timber-line is principally a function of temperature. Palaeolimnological investigations have shown significant shifts in phyto- and zoo-plankton populations as alpine lakes shift between being above or below the timber-line. Likewise, streamside vegetation has a significant effect on stream ecosystem structure and function. Changes in stream temperature regimes result in significant changes in community composition as a consequence of bioenergetic factors. Stenothermic species could be extirpated as

  4. Does life history predict past and current connectivity for rocky intertidal invertebrates across a marine biogeographic barrier?

    PubMed

    Ayre, D J; Minchinton, T E; Perrin, C

    2009-05-01

    The southeast Australian coast potentially includes a complex biogeographic barrier, largely lacking exposed rocky shore that may limit the dispersal of rocky intertidal taxa and contribute to the maintenance of two biogeographic regions. Surprisingly, within the 300-km barrier region, several species considered exposed rocky shore specialists occurred within sheltered sites. We analysed COI sequence variation for 10 rocky intertidal invertebrate species, with a range of life histories, to test the hypotheses that larval type and habitat specificity are strong predictors of gene flow between biogeographic regions. Our data revealed that the southeast corner of Australia includes a strong barrier to gene flow for six of eight species with planktonic larvae, and a coalescence analysis of sequence differentiation (IM model) suggests that a barrier has existed since the Pleistocene. In contrast, two direct developers were not affected by the barrier. Our comparative approach and data from earlier studies (reviewed here) do not support the hypothesis that larval type predicts gene flow across this barrier, instead we found that the ability to utilize sheltered habitat provides a clearer explanation of the phylogeographic break. Indeed, the species that displayed little or no evidence of a phylogeographic break across the barrier each displayed unexpectedly relaxed habitat specificity.

  5. Realistic changes in seaweed biodiversity affect multiple ecosystem functions on a rocky shore.

    PubMed

    Bracken, Matthew E S; Williams, Susan L

    2013-09-01

    Given current threats to biodiversity, understanding the effects of diversity changes on the functions and services associated with intact ecosystems is of paramount importance. However, limited realism in most biodiversity studies makes it difficult to link the large and growing body of evidence for important functional consequences of biodiversity change to real-world losses of biodiversity. Here, we explored two methods of incorporating realism into biodiversity research: (1) the use of two-, five-, and eight-species assemblages that mimicked those that we observed in surveys of seaweed biodiversity patterns on a northern California (USA) rocky shore and the explicit comparison of those assemblages to random assemblages compiled from the same local species pool; and (2) the measurement of two fundamental ecosystem functions, nitrate uptake and photosynthesis, both of which contribute to growth of primary producers. Specifically, we measured nitrate uptake rates of seaweed assemblages as a function of initial nitrate concentrations and photosynthetic rates as a function of irradiance levels for both realistic and random assemblages of seaweeds. We only observed changes in ecosystem functioning along a richness gradient for realistic assemblages, and both maximum nitrate uptake rates (V(max)) and photosynthetic light use efficiency values (alpha(p) = P(max)/I(K)) were higher in realistic assemblages than in random assemblages. Furthermore, the parameter affected by changes in richness depended on the function being measured. Both V(max) and alpha(p) declined with increasing richness in nonrandom assemblages due to a combination of species identity effects (for V(max) and overyielding effects (for both V(max) and alpha(p)). In contrast, neither nitrate uptake efficiency values (alpha(N) = V(max)/K(s)), nor maximum photosynthetic rates (Pmax) changed along the gradient in seaweed species richness. Furthermore, overyielding was only evident in realistic assemblages

  6. Land-Cover Change Within the Peatlands Along the Rocky Mountain Front, Montana: 1937-2009

    NASA Astrophysics Data System (ADS)

    Klene, A. E.; Milbrath, J. T.; Shelly, J. S.

    2013-12-01

    While peatlands are globally abundant, the fens of the Rocky Mountain Front (RMF), are the eastern-most, rich, peatlands in Montana, and are unique wetland habitats in this region of semi-arid continental climate. The peatlands provide critical riparian connectivity between the mountains and the plains and are habitat for grizzly bears, wolves, and within just the 450 ha Pine Butte Fen at least 93 species of vascular plants, including seven of Montana's Plant Species of Concern. Aerial photographs of the nine peatlands along the RMF in Montana were analyzed in a GIS. The boundary of each wetland was hand-digitized and the area within was classified into land-cover types: total area, open fen, open water, woody vegetation, and non-wetland/agriculture. Changes in wetland extent and land-cover categories were evaluated from the earliest available imagery in 1937 to the last available imagery in 2009. Images prior to 1995 were orthorectified, and all georectified. Climate change, wildlife, and agriculture were examined as potential drivers of land-cover change at these sites. Results indicate little change in overall peatland area between 1937 and 2009 despite increasing air temperatures in the region. Approximately 16% of these peatlands is 'open fen' and that proportion remained stable over the last seventy years. Area of open water quadrupled and the number of ponds which could be delineated tripled over the study period, reflecting a recovering beaver population. The non-wetland/agricultural area halved over the course of the study, primarily due to declines in agriculture within the three largest remaining peatlands: Pine Butte Fen, McDonald Swamp, and the Blackleaf Creek wetland complex. Most of the first two fens were purchased outright by the Nature Conservancy (TNC) and they hold a conservation easement on the third (as well as two other fens), all of which have been been put in place since the late 1970s. One fen is owned by the State of Montana and another

  7. Marine ecosystem responses to Cenozoic global change.

    PubMed

    Norris, R D; Turner, S Kirtland; Hull, P M; Ridgwell, A

    2013-08-02

    The future impacts of anthropogenic global change on marine ecosystems are highly uncertain, but insights can be gained from past intervals of high atmospheric carbon dioxide partial pressure. The long-term geological record reveals an early Cenozoic warm climate that supported smaller polar ecosystems, few coral-algal reefs, expanded shallow-water platforms, longer food chains with less energy for top predators, and a less oxygenated ocean than today. The closest analogs for our likely future are climate transients, 10,000 to 200,000 years in duration, that occurred during the long early Cenozoic interval of elevated warmth. Although the future ocean will begin to resemble the past greenhouse world, it will retain elements of the present "icehouse" world long into the future. Changing temperatures and ocean acidification, together with rising sea level and shifts in ocean productivity, will keep marine ecosystems in a state of continuous change for 100,000 years.

  8. Effect of climate change on marine ecosystems

    NASA Astrophysics Data System (ADS)

    Vikebo, F. B.; Sundby, S.; Aadlandsvik, B.; Fiksen, O.

    2003-04-01

    As a part of the INTEGRATION project, headed by Potsdam Institute for Climate Impact Research, funded by the German Research Council, the impact of climate change scenarios on marine fish populations will be addressed on a spesific population basis and will focus on fish populations in the northern North Atlantic with special emphasis on cod. The approach taken will mainly be a modelling study supported by analysis of existing data on fish stocks and climate. Through down-scaling and nesting techniques, various climate change scenarios with reduced THC in the North Atlantic will be investigated with higher spatial resolution for selected shelf areas. The hydrodynamical model used for the regional ocean modeling is ROMS (http://marine.rutgers.edu/po/models/roms/). An individual based model will be implemented into the larval drift module to simulate growth of the larvae along the drift paths.

  9. Land use change and nitrogen enrichment of a Rocky Mountain watershed.

    PubMed

    Kaushal, Sujay S; Lewis, William M; McCutchan, James H

    2006-02-01

    Headwater ecosystems may have a limited threshold for retaining and removing nutrients delivered by certain types of land use. Nitrogen enrichment was studied in a Rocky Mountain watershed undergoing rapid expansion of population and residential development. Study sites were located along a 30-km transect from the headwaters of the Blue River to Lake Dillon, a major source of drinking water for Denver, Colorado. Ground water in residential areas with septic systems showed high concentrations of nitrate-N (4.96 +/- 1.22 mg/L, mean +/- SE), and approximately 40% of wells contained nitrate with delta15N values in the range of wastewater. Concentrations of dissolved inorganic nitrogen (DIN) in tributaries with residential development peaked during spring snowmelt as concentrations of DIN declined to below detection limits in undeveloped tributaries. Annual export of dissolved organic nitrogen (DON) was considerably lower in residential streams, suggesting a change in forms of N with development. The seasonal delta15N of algae in residential streams was intermediate between baseline values from undeveloped streams and stream algae grown on wastewater. Between 19% and 23% of the annual N export from developed tributaries was derived from septic systems, as estimated from the delta15N of algae. This range was similar to the amount of N export above background determined independently from mass-balance estimates. From a watershed perspective, total loading of N to the Blue River catchment from septic and municipal wastewater (2 kg x ha(-1) x yr(-1)) is currently less than the amount from background atmospheric sources (3 kg x ha(-1) x yr(-1)). Nonetheless, nitrate-N concentrations exceeded limits for safe drinking water in some groundwater wells (10 mg/L), residential streams showed elevated seasonal patterns of nitrate-N concentration and ratios of DIN to total dissolved phosphorus, and seasonal minimum concentrations of nitrate-N in Lake Dillon have increased

  10. Potential of marine reserves to cause community-wide changes beyond their boundaries.

    PubMed

    Guidetti, Paolo

    2007-04-01

    Fishing and other human activities can alter the abundances, size structure, and behavior of species playing key roles in shaping marine communities (e.g., keystone predators), which may in turn cause ecosystem shifts. Despite extensive evidence that cascading trophic interactions can underlie community-wide recovery inside no-take marine reserves by protecting high-level predators, the spatial extent of these effects into adjacent fished areas is unknown. I examined the potential for community-wide changes (i.e., the transition from overgrazed coralline barrens to macroalgal beds) in temperate rocky reefs within and around a no-take marine reserve. For this purpose I assessed distribution patterns of predatory fishes, sea urchins, and barrens across the reserve boundaries. Predatory fishes were significantly more abundant within the reserve than in adjacent locations, with moderate spillover across the reserve edges. In contrast, community-wide changes of benthic assemblages were apparent well beyond the reserve boundaries, which is consistent with temporary movements of predatory fishes (e.g., foraging migration) from the reserve to surrounding areas. My results suggest that no-take marine reserves can promote community-wide changes beyond their boundaries.

  11. 77 FR 43511 - Special Local Regulations for Marine Events, Temporary Change of Dates for Recurring Marine...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-25

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulations for Marine Events, Temporary Change of Dates for Recurring Marine Events in the Fifth Coast Guard District, Wrightsville Channel... temporarily changing the enforcement period of one special local regulation for a recurring marine event...

  12. 76 FR 55561 - Special Local Regulations for Marine Events; Temporary Change of Dates for Recurring Marine...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-08

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulations for Marine Events; Temporary Change of Dates for Recurring Marine Events in the Fifth Coast Guard District, Wrightsville Channel... temporarily change the enforcement period of one special local regulation for a recurring marine event in...

  13. Marine ecology: gelatinous bells may ring change in marine ecosystems.

    PubMed

    Hay, Steve

    2006-09-05

    Gelatinous plankton are critical components of marine ecosystems. Recent studies are providing evidence of increased population outbursts of such species. Jellyfish seem to respond when an ecosystem is over-fished, and their ecology is under-researched.

  14. 77 FR 39453 - Special Local Regulations for Marine Events; Temporary Change of Dates for Recurring Marine...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-03

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625--AA08 Special Local Regulations for Marine Events; Temporary Change of Dates for Recurring Marine Events in the Fifth Coast Guard District, Bogue Sound; Morehead City... regulation of a recurring marine event in the Fifth Coast Guard District. The proposed rule was initiated...

  15. 76 FR 44877 - Special Local Regulations for Marine Events; Temporary Change of Dates for Recurring Marine...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-27

    .... USCG-2011-0629] RIN 1625-AA08 Special Local Regulations for Marine Events; Temporary Change of Dates for Recurring Marine Events in the Fifth Coast Guard District, Wrightsville Channel; Wrightsville... marine event in the Fifth Coast Guard District. The ``Wilmington YMCA Triathlon,'' conducted on...

  16. 77 FR 30929 - Special Local Regulations for Marine Events, Temporary Change of Dates for Recurring Marine...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-24

    ... Number USCG-2012-0341] RIN 1625-AA08 Special Local Regulations for Marine Events, Temporary Change of Dates for Recurring Marine Events in the Fifth Coast Guard District, Wrightsville Channel; Wrightsville... marine event in the Fifth Coast Guard District, specifically the ``Wilmington YMCA Triathlon'',...

  17. 76 FR 57645 - Special Local Regulations for Marine Events; Temporary Change of Dates for Recurring Marine...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-16

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulations for Marine Events; Temporary Change of Dates for Recurring Marine Events in the Fifth Coast Guard District, Wrightsville Channel... following correction is made: Sec. 100.501 Special Local Regulations; Marine Events in the Fifth Coast...

  18. Human exclusion from rocky shores in a mediterranean marine protected area (MPA): an opportunity to investigate the effects of trampling.

    PubMed

    Casu, Daniela; Ceccherelli, Giulia; Curini-Galletti, Marco; Castelli, Alberto

    2006-07-01

    The effect of human trampling on the abundance of small invertebrates inhabiting rocky shallow bottoms was studied at Asinara Island MPA. To this aim we have conducted two experiments. The first was a quantitative study and tested the hypothesis that small invertebrates are more abundant at no-entry locations than at the location visited by tourists through time (before, during and after tourist season). The second was a manipulative experiment and tested the hypothesis that the abundance of small invertebrates is indirectly related to experimental trampling intensities. The effect due to tourist visitation was not highlighted on overall assemblages, suggesting that present seasonal tourist load at the MPA does not cause a significantly negative effect on the zoobenthic community studied. Although tourists exhibited trampling activity at the visited location, none of taxa examined showed a significant lower abundance during and strictly after the end of seasonal tourism peak in the visited location, rather than at control locations. However, results obtained with the second experiment suggested that the effects of different experimental trampling intensities on small invertebrates were variable among taxa. The experimental trampling caused immediate declines in the density of tanaids, nematodes, acari, bivalves, gammarids, echinoderms, isopods, and harpacticoids. For some of these taxa a recovery in abundance was observed within one month. This kind of data may offer important information to estimate the number of visitors compatible with the sensitivity of zoobenthic assemblages, and may substantially contribute to appropriate MPA management.

  19. Global change and marine communities: alien species and climate change.

    PubMed

    Occhipinti-Ambrogi, Anna

    2007-01-01

    Anthropogenic influences on the biosphere since the advent of the industrial age are increasingly causing global changes. Climatic change and the rising concentration of greenhouse gases in the atmosphere are ranking high in scientific and public agendas, and other components of global change are also frequently addressed, among which are the introductions of non indigenous species (NIS) in biogeographic regions well separated from the donor region, often followed by spectacular invasions. In the marine environment, both climatic change and spread of alien species have been studied extensively; this review is aimed at examining the main responses of ecosystems to climatic change, taking into account the increasing importance of biological invasions. Some general principles on NIS introductions in the marine environment are recalled, such as the importance of propagule pressure and of development stages during the time course of an invasion. Climatic change is known to affect many ecological properties; it interacts also with NIS in many possible ways. Direct (proximate) effects on individuals and populations of altered physical-chemical conditions are distinguished from indirect effects on emergent properties (species distribution, diversity, and production). Climatically driven changes may affect both local dispersal mechanisms, due to the alteration of current patterns, and competitive interactions between NIS and native species, due to the onset of new thermal optima and/or different carbonate chemistry. As well as latitudinal range expansions of species correlated with changing temperature conditions, and effects on species richness and the correlated extinction of native species, some invasions may provoke multiple effects which involve overall ecosystem functioning (material flow between trophic groups, primary production, relative extent of organic material decomposition, extent of benthic-pelagic coupling). Some examples are given, including a special

  20. Modeled subalpine plant community response to climate change and atmospheric nitrogen deposition in Rocky Mountain National Park, USA.

    PubMed

    McDonnell, T C; Belyazid, S; Sullivan, T J; Sverdrup, H; Bowman, W D; Porter, E M

    2014-04-01

    To evaluate potential long-term effects of climate change and atmospheric nitrogen (N) deposition on subalpine ecosystems, the coupled biogeochemical and vegetation community competition model ForSAFE-Veg was applied to a site at the Loch Vale watershed of Rocky Mountain National Park, Colorado. Changes in climate and N deposition since 1900 resulted in pronounced changes in simulated plant species cover as compared with ambient and estimated future community composition. The estimated critical load (CL) of N deposition to protect against an average future (2010-2100) change in biodiversity of 10% was between 1.9 and 3.5 kg N ha(-1) yr(-1). Results suggest that the CL has been exceeded and vegetation at the study site has already undergone a change of more than 10% as a result of N deposition. Future increases in air temperature are forecast to cause further changes in plant community composition, exacerbating changes in response to N deposition alone.

  1. Climate Change and Water Quality in the Rocky Mountains: challenges of too much summer for addressing acid rock drainage (Invited)

    NASA Astrophysics Data System (ADS)

    McKnight, D. M.; Crouch, C. M.; Rue, G. P.

    2013-12-01

    A major water quality concern in the Rocky Mountains is acid rock drainage, which causes acidic conditions and high metal concentrations. The 30-year water quality record for the Snake River watershed in Colorado, USA, shows that for the summer low-flow period zinc concentrations have increased four- to six-fold concurrently with a two- to three week advancement in spring snowmelt. We found that the main source of acidity, zinc and other metals, including rare earth elements to the upper Snake River was a tributary draining an alpine area rich in disseminated pyrite. By conducting a tracer experiment in this tributary, we demonstrated that more than half of the trace metal and acidity loading entered in an upper steep, rocky reach where the tributary is fed by an alpine spring. Another increase in flow and metal loading occurred where the tributary flows through a gently-sloped wetland area containing a bog iron deposit. Analysis of the tracer experiment indicated a significant increase in hyporheic exchange along this wetland reach, where decreases in pH of the water exchanging in the hyporheic zone may be mobilizing metals that had been sequestered in the wetland through sorption to iron oxides. One possible scenario is that decreasing pH in the upper reach has reached a threshold, resulting in mobilization of metals from the hyporheic zone of the wetland. This study illustrates how changes in hydrologic regime may cause changes in biogeochemical processes that exacerbate the danger to aquatic ecosystems associated with acid rock drainage.

  2. 77 FR 15320 - Special Local Regulations for Marine Events; Temporary Change of Dates for Recurring Marine...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-15

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulations for Marine Events; Temporary Change of Dates for Recurring Marine Events in the Fifth Coast Guard District, Bogue Sound; Morehead City... event in the Fifth Coast Guard District. This change applies only to the ``Crystal Coast Super...

  3. Climate Change Impacts on Marine Ecosystems

    NASA Astrophysics Data System (ADS)

    Doney, Scott C.; Ruckelshaus, Mary; Emmett Duffy, J.; 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.

  4. Response of rocky reef top predators (Serranidae: Epinephelinae) in and around marine protected areas in the Western Mediterranean Sea.

    PubMed

    Hackradt, Carlos Werner; García-Charton, José Antonio; Harmelin-Vivien, Mireille; Pérez-Ruzafa, Ángel; Le Diréach, Laurence; Bayle-Sempere, Just; Charbonnel, Eric; Ody, Denis; Reñones, Olga; Sanchez-Jerez, Pablo; Valle, Carlos

    2014-01-01

    Groupers species are extremely vulnerable to overfishing and many species are threatened worldwide. In recent decades, Mediterranean groupers experienced dramatic population declines. Marine protected areas (MPAs) can protect populations inside their boundaries and provide individuals to adjacent fishing areas through the process of spillover and larval export. This study aims to evaluate the effectiveness of six marine reserves in the Western Mediterranean Sea to protect the populations of three species of grouper, Epinephelus marginatus, Epinephelus costae and Mycteroperca rubra, and to understand in which circumstances MPAs are able to export biomass to neighbouring areas. All the studied MPAs, except one where no grouper was observed, were able to maintain high abundance, biomass and mean weight of groupers. Size classes were more evenly distributed inside than outside MPAs. In two reserves, biomass gradients could be detected through the boundaries of the reserve as an indication of spillover. In some cases, habitat structure appeared to exert a great influence on grouper abundance, biomass and mean individual weight, influencing the gradient shape. Because groupers are generally sedentary animals with a small home range, we suggest that biomass gradients could only occur where groupers attain sufficient abundance inside MPA limits, indicating a strongly density-dependent process.

  5. Response of Rocky Reef Top Predators (Serranidae: Epinephelinae) in and Around Marine Protected Areas in the Western Mediterranean Sea

    PubMed Central

    Hackradt, Carlos Werner; García-Charton, José Antonio; Harmelin-Vivien, Mireille; Pérez-Ruzafa, Ángel; Le Diréach, Laurence; Bayle-Sempere, Just; Charbonnel, Eric; Ody, Denis; Reñones, Olga; Sanchez-Jerez, Pablo; Valle, Carlos

    2014-01-01

    Groupers species are extremely vulnerable to overfishing and many species are threatened worldwide. In recent decades, Mediterranean groupers experienced dramatic population declines. Marine protected areas (MPAs) can protect populations inside their boundaries and provide individuals to adjacent fishing areas through the process of spillover and larval export. This study aims to evaluate the effectiveness of six marine reserves in the Western Mediterranean Sea to protect the populations of three species of grouper, Epinephelus marginatus, Epinephelus costae and Mycteroperca rubra, and to understand in which circumstances MPAs are able to export biomass to neighbouring areas. All the studied MPAs, except one where no grouper was observed, were able to maintain high abundance, biomass and mean weight of groupers. Size classes were more evenly distributed inside than outside MPAs. In two reserves, biomass gradients could be detected through the boundaries of the reserve as an indication of spillover. In some cases, habitat structure appeared to exert a great influence on grouper abundance, biomass and mean individual weight, influencing the gradient shape. Because groupers are generally sedentary animals with a small home range, we suggest that biomass gradients could only occur where groupers attain sufficient abundance inside MPA limits, indicating a strongly density-dependent process. PMID:24905331

  6. Polar Marine Microorganisms and Climate Change.

    PubMed

    Verde, C; Giordano, D; Bellas, C M; di Prisco, G; Anesio, A M

    2016-01-01

    The large diversity of marine microorganisms harboured by oceans plays an important role in planet sustainability by driving globally important biogeochemical cycles; all primary and most secondary production in the oceans is performed by microorganisms. The largest part of the planet is covered by cold environments; consequently, cold-adapted microorganisms have crucial functional roles in globally important environmental processes and biogeochemical cycles cold-adapted extremophiles are a remarkable model to shed light on the molecular basis of survival at low temperature. The indigenous populations of Antarctic and Arctic microorganisms are endowed with genetic and physiological traits that allow them to live and effectively compete at the temperatures prevailing in polar regions. Some genes, e.g. glycosyltransferases and glycosylsynthetases involved in the architecture of the cell wall, may have been acquired/retained during evolution of polar strains or lost in tropical strains. This present work focusses on temperature and its role in shaping microbial adaptations; however, in assessing the impacts of climate changes on microbial diversity and biogeochemical cycles in polar oceans, it should not be forgotten that physiological studies need to include the interaction of temperature with other abiotic and biotic factors.

  7. Changes in marine dinoflagellate and diatom abundance under climate change

    NASA Astrophysics Data System (ADS)

    Hinder, Stephanie L.; Hays, Graeme C.; Edwards, Martin; Roberts, Emily C.; Walne, Anthony W.; Gravenor, Mike B.

    2012-04-01

    Marine diatoms and dinoflagellates play a variety of key ecosystem roles as important primary producers (diatoms and some dinoflagellates) and grazers (some dinoflagellates). Additionally some are harmful algal bloom (HAB) species and there is widespread concern that HAB species may be increasing accompanied by major negative socio-economic impacts, including threats to human health and marine harvesting. Using 92,263 samples from the Continuous Plankton Recorder survey, we generated a 50-year (1960-2009) time series of diatom and dinoflagellate occurrence in the northeast Atlantic and North Sea. Dinoflagellates, including both HAB taxa (for example, Prorocentrum spp.) and non-HAB taxa (for example, Ceratium furca), have declined in abundance, particularly since 2006. In contrast, diatom abundance has not shown this decline with some common diatoms, including both HAB (for example, Pseudo-nitzschia spp.) and non-HAB (for example, Thalassiosira spp.) taxa, increasing in abundance. Overall these changes have led to a marked increase in the relative abundance of diatoms versus dinoflagellates. Our analyses, including Granger tests to identify criteria of causality, indicate that this switch is driven by an interaction effect of both increasing sea surface temperatures combined with increasingly windy conditions in summer.

  8. 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.

  9. 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.

  10. Forecasting distributional responses of limber pine to climate change at management-relevant scales in Rocky Mountain National Park.

    PubMed

    Monahan, William B; Cook, Tammy; Melton, Forrest; Connor, Jeff; Bobowski, Ben

    2013-01-01

    Resource managers at parks and other protected areas are increasingly expected to factor climate change explicitly into their decision making frameworks. However, most protected areas are small relative to the geographic ranges of species being managed, so forecasts need to consider local adaptation and community dynamics that are correlated with climate and affect distributions inside protected area boundaries. Additionally, niche theory suggests that species' physiological capacities to respond to climate change may be underestimated when forecasts fail to consider the full breadth of climates occupied by the species rangewide. Here, using correlative species distribution models that contrast estimates of climatic sensitivity inferred from the two spatial extents, we quantify the response of limber pine (Pinus flexilis) to climate change in Rocky Mountain National Park (Colorado, USA). Models are trained locally within the park where limber pine is the community dominant tree species, a distinct structural-compositional vegetation class of interest to managers, and also rangewide, as suggested by niche theory. Model forecasts through 2100 under two representative concentration pathways (RCP 4.5 and 8.5 W/m(2)) show that the distribution of limber pine in the park is expected to move upslope in elevation, but changes in total and core patch area remain highly uncertain. Most of this uncertainty is biological, as magnitudes of projected change are considerably more variable between the two spatial extents used in model training than they are between RCPs, and novel future climates only affect local model predictions associated with RCP 8.5 after 2091. Combined, these results illustrate the importance of accounting for unknowns in species' climatic sensitivities when forecasting distributional scenarios that are used to inform management decisions. We discuss how our results for limber pine may be interpreted in the context of climate change vulnerability and used

  11. Canadian Rockies Ecoregion: Chapter 4 in Status and trends of land change in the Western United States--1973 to 2000

    USGS Publications Warehouse

    Taylor, Janis L.

    2012-01-01

    The Canadian Rockies Ecoregion covers approximately 18,494 km2 (7,141 mi2) in northwestern Montana (Omernik, 1987; U.S. Environmental Protection Agency, 1997). The east side of the ecoregion is bordered by the Montana Valley and Foothill Prairies Ecoregion, which also forms a large part of the western border of the ecoregion. In addition, the Northern Rockies Ecoregion wraps around the ecoregion to the northwest and south (fig. 1). As the name implies, the Canadian Rocky Mountains are located mostly in Canada, straddling the border between Alberta and British Columbia. However, this ecoregion only includes the part of the northern Rocky Mountains that is in the United States. This ecoregion is characterized by steep, high-elevation mountain ranges similar to most of the rest of the Rocky Mountains. Compared to the Northern Rockies Ecoregion, however, the Canadian Rockies Ecoregion reaches higher elevations and contains a greater proportion of perennial snow and ice (Omernik, 1987) (fig. 2). Over the years, this section of the Rocky Mountains has garnered many different names, including “Crown of the Continent” by George Bird Grinnell (Waldt, 2008) and “Backbone of the World” by the Blackfeet (Pikuni) Nation. Throughout the ecoregion, montane, subalpine, and alpine ecosystems have distinct flora and fauna elevation zones. Glaciers, permanent snowfields, and seasonal snowpack are found at the highest elevations. Spring and summer runoff fills lakes and tarns that form the headwaters of numerous streams and rivers, including the Columbia and Missouri Rivers that flow west and east, respectively, from the Continental Divide.

  12. Differential insect and mammalian response to Late Quaternary climate change in the Rocky Mountain region of North America

    NASA Astrophysics Data System (ADS)

    Elias, Scott A.

    2015-07-01

    Of the 200 beetle species identified from Rocky Mountain Late Pleistocene insect faunal assemblages, 23% are no longer resident in this region. None of the 200 species is extinct. In contrast to this, only 8% of 73 identified mammal species from Rocky Mountain Late Pleistocene assemblages are no longer resident in the Rockies, and 12 species are now extinct. Since both groups of organisms are highly mobile, it would appear that their responses to the large-scale fluctuations of climate associated with the last 125,000 years have been considerably different. Most strikingly contrasting with the insects, there are no mammals in the Rocky Mountain Late Pleistocene fossil record that are found exclusively today in the Pacific Northwest (PNW) region. The PNW does have a distinctive modern mammalian fauna, but only one of these, Keen's Myotis, has a fossil record outside the PNW region, in the eastern and central United States. No modern PNW vertebrate species have been found in any Rocky Mountain fossil assemblages. Based on these data, it appears that there has been little or no mammalian faunal exchange between the PNW region and the Rocky Mountains during the Late Pleistocene or Holocene. This is in stark contrast to the fossil beetle record, where PNW species are a substantial component in many faunas, right through to the Late Holocene.

  13. High-elevation paleoenvironmental change during MIS 6-4 in the central Rockies of Colorado as determined from pollen analysis

    NASA Astrophysics Data System (ADS)

    Anderson, R. Scott; Jiménez-Moreno, Gonzalo; Ager, Thomas; Porinchu, David F.

    2014-11-01

    Paleoecological studies from Rocky Mountain (USA) high elevations encompassing the previous interglacial (MIS 5e) are rare. The ~ 10-m composite profile from the Ziegler Reservoir fossil site (2705 m asl) of central Colorado allows us to determine paleoenvironments from Marine Oxygen Isotope Stages (MIS) 6- 4 using pollen zones that are approximately equivalent to marine oxygen isotope stages. During Pollen Zone (PZ) 6 time, pollen assemblages dominated by Artemisia (sagebrush) suggest that alpine tundra or steppe occurred nearby. The transition to PZ 5e was characterized by a rapid increase in tree pollen, initially Picea (spruce) and Pinus (pine) but also Quercus (oak) and Pseudotsuga menziesii (Douglas-fir). Non-arboreal pollen (NAP) types increased during PZ 5d, while Abies (fir) and Juniperus (juniper) increased during PZ 5c. Pollen evidence suggests that temperatures during PZ 5b were as cold as during PZ 6, with the site again surrounded by alpine tundra. Picea dominated during PZ 5a before the onset of cooler conditions during PZ 4. The MIS 6-MIS 5e transition here was similar to the MIS 2-MIS 1 transition at other Rocky Mountain sites. However, the Ziegler Reservoir pollen record contains evidence suggesting unexpected climatic trends at this site, including a warmer-than-expected MIS 5d and cooler-than-expected MIS 5b.

  14. Regional Climate Change Influences Frequency of Frost Damage via Changes in Phenology: Effects of the North Pacific Oscillation (Pacific Decadal Oscillation) on Rocky Mountain Wildflowers

    NASA Astrophysics Data System (ADS)

    Inouye, D. W.

    2004-12-01

    There is a significant correlation (P = .049) between the state of the North Pacific Oscillation (Pacific Decadal Oscillation) and the amount of winter snowfall at the Rocky Mountain Biological Laboratory (2,800m in the Colorado Rocky Mountains). The 1998 change of this inter-decadal mode of variability of the north Pacific atmosphere system to a dry phase has resulted in decreased snowpack, reversing a trend for increasing snowfall since the previous phase change in 1976. The seasonal timing (phenology) of plant growth and flowering at high altitudes is determined almost entirely by the timing of spring snowmelt, even for species that flower at the end of the season, and the decreased snowpack since 1998 combined with warming air temperatures has resulted in significantly earlier initiation of the growing season and subsequent flowering. Flowering in 2002, for example, was the earliest recorded during my 31-year study, and probably the earliest since at least 1935. Frost (with temperatures as low as -6 or -7ºC) is still likely to occur as late as mid-June, however, and a consequence of the earlier beginning of the growing season is that many species have developed sensitive flower buds or other tissues by mid-June that are likely to be killed by frost. From 1994-1998 the average percentage of flower buds of Helianthella quinquenervis (Asteraceae; aspen sunflower) killed by frost was 26 percent(range 0-81), but since the 1998 NPO phase change a mean of 75 percent of flower buds have been killed (range 0-100; over 90 percent for each of the past four years). The loss of flowers from these frosts has consequences for plant demography (fewer seeds results in fewer seedlings), pollinators (which have fewer floral resources), seed predators (e.g., tephritid flies), and parasitoids (e.g., wasps, which have fewer seed predators to parasitize). A suite of wildflower species whose flowering abundance is positively correlated with the amount of winter snowfall has also

  15. High-resolution regional climate simulations of precipitation and snowpack over the US northern Rockies in a changing climate

    NASA Astrophysics Data System (ADS)

    Wang, Y.; Geerts, B.; Liu, C.

    2015-12-01

    This work first examines the performance of a regional climate model in capturing orographic precipitation and snowpack dynamics in the northern US Rockies. The Weather Research and Forecasting (WRF) model is run at a sufficiently fine resolution (4-km horizontal grid spacing), over a sub-continental domain driven by the Climate Forecast System Reanalysis (CFSR), to examine WRF's ability to simulate the observed seasonal precipitation and snowpack dynamics. WRF retrospective simulations are being run over a 30-year period from 1980 to 2010. Observations from Snow Telemetry (SNOTEL, providing precipitation rate and snowpack snow water equivalent (SWE)) and the Parameter-elevation Regressions on Independent Slopes Model (PRISM, providing fine-scale monthly mean values of precipitation and temperature) are used for validation. The results show that WRF captures observed seasonal precipitation and snowpack build-up reasonably well. The second part of this work is in progress. A pseudo-global warming (PGW) technique is used to perturb the retrospective reanalysis with the anticipated change according to the consensus global model guidance under the CMIP5 "high emissions" (RCP8.5) scenario produced by the CCSM4. This technique preserves low-frequency general circulation patterns and the characteristics of storms entering the domain. The WRF model is rerun over 30 years centered on 2050 with perturbed initial and boundary conditions. The results will be used to examine the effect of climate variability and projected global warming on the statistical distributions of precipitation amounts and SWE in the studied domain.

  16. Computing Risk to West Coast Intertidal Rocky Habitat due to ...

    EPA Pesticide Factsheets

    Compared to marshes, little information is available on the potential for rocky intertidal habitats to migrate upward in response to sea level rise (SLR). To address this gap, we utilized topobathy LiDAR digital elevation models (DEMs) downloaded from NOAA’s Digital Coast GIS data repository to estimate percent change in the area of rocky intertidal habitat in 10 cm increments with eustatic sea level rise. The analysis was conducted at the scale of the four Marine Ecoregions of the World (MEOW) ecoregions located along the continental west coast of the United States (CONUS). Environmental Sensitivity Index (ESI) map data were used to identify rocky shoreline. Such stretches of shoreline were extracted for each of the four ecoregions and buffered by 100 m to include the intertidal and evaluate the potential area for upland habitat migration. All available LiDAR topobathy DEMs from Digital Coast were extracted using the resulting polygons and two rasters were synthesized from the results, a 10 cm increment zone raster and a non-planimetric surface area raster for zonal summation. Current rocky intertidal non-planimetric surface areas for each ecoregion were computed between Mean Higher High Water (MHHW) and Mean Lower Low Water (MLLW) levels established from published datum sheets for tidal stations central to each MEOW ecoregion. Percent change in non-planimetric surface area for the same relative ranges were calculated in 10 cm incremental steps of eustatic S

  17. An Assessment of Fire Regime Changes in the Northern Rocky Mountain Region Using Simulated Historical Fire Maps and Remotely Sensed Current Fires

    NASA Astrophysics Data System (ADS)

    Zhao, F.; Zhu, Z.; Huang, C.

    2011-12-01

    Wildland fire is a primary ecosystem process that shapes the landscape of Western United States. Changes in fire regime can therefore have profound impact on ecosystem functions and services, including carbon cycling, habitat conditions, and biodiversity. This poster presents a study on current fire regime and changes in the Northern Rocky Mountain region assessed using contemporary and historical fire regimes. Contemporary fire records from 1984 to 2008 were obtained from the Monitoring Trends in Burn Severity (MTBS) project. Historical (pre-EuroAmerican settlement) fire regimes and fire regime condition class (FRCC), produced by the LANDFIRE project, were simulated using a Landscape Succession Model (LANDSUM). We extracted historical fire frequency (Mean Fire Interval) and fire severity (percentage of severe fire) data from LANDFIRE, and calculated current fire frequency and severity using MTBS data by following the FRCC definition, to evaluate changes in fire regimes in Northern Rocky Mountain area. Preliminary results reveal that the current fire regime in Northern Rocky Mountains may exhibit a general pattern of longer return intervals and more severe fires. Biophysical Setting (BpS) map units from LANDFIRE are used as study units to describe environmental gradients and will be used to further examine whether the observed fire regime changes are controlled by land cover or biophysical settings. The findings of this study will help reveal contemporary fire dynamics in this region and serve for future fire studies and other forest management applications.

  18. Climate change impact on seaweed meadow distribution in the North Atlantic rocky intertidal

    PubMed Central

    Jueterbock, Alexander; Tyberghein, Lennert; Verbruggen, Heroen; Coyer, James A; Olsen, Jeanine L; Hoarau, Galice

    2013-01-01

    The North-Atlantic has warmed faster than all other ocean basins and climate change scenarios predict sea surface temperature isotherms to shift up to 600 km northwards by the end of the 21st century. The pole-ward shift has already begun for many temperate seaweed species that are important intertidal foundation species. We asked the question: Where will climate change have the greatest impact on three foundational, macroalgal species that occur along North-Atlantic shores: Fucus serratus, Fucus vesiculosus, and Ascophyllum nodosum? To predict distributional changes of these key species under three IPCC (Intergovernmental Panel on Climate Change) climate change scenarios (A2, A1B, and B1) over the coming two centuries, we generated Ecological Niche Models with the program MAXENT. Model predictions suggest that these three species will shift northwards as an assemblage or “unit” and that phytogeographic changes will be most pronounced in the southern Arctic and the southern temperate provinces. Our models predict that Arctic shores in Canada, Greenland, and Spitsbergen will become suitable for all three species by 2100. Shores south of 45° North will become unsuitable for at least two of the three focal species on both the Northwest- and Northeast-Atlantic coasts by 2200. If these foundational species are unable to adapt to the rising temperatures, they will lose their centers of genetic diversity and their loss will trigger an unpredictable shift in the North-Atlantic intertidal ecosystem. PMID:23762521

  19. Climate change impact on seaweed meadow distribution in the North Atlantic rocky intertidal.

    PubMed

    Jueterbock, Alexander; Tyberghein, Lennert; Verbruggen, Heroen; Coyer, James A; Olsen, Jeanine L; Hoarau, Galice

    2013-05-01

    The North-Atlantic has warmed faster than all other ocean basins and climate change scenarios predict sea surface temperature isotherms to shift up to 600 km northwards by the end of the 21st century. The pole-ward shift has already begun for many temperate seaweed species that are important intertidal foundation species. We asked the question: Where will climate change have the greatest impact on three foundational, macroalgal species that occur along North-Atlantic shores: Fucus serratus, Fucus vesiculosus, and Ascophyllum nodosum? To predict distributional changes of these key species under three IPCC (Intergovernmental Panel on Climate Change) climate change scenarios (A2, A1B, and B1) over the coming two centuries, we generated Ecological Niche Models with the program MAXENT. Model predictions suggest that these three species will shift northwards as an assemblage or "unit" and that phytogeographic changes will be most pronounced in the southern Arctic and the southern temperate provinces. Our models predict that Arctic shores in Canada, Greenland, and Spitsbergen will become suitable for all three species by 2100. Shores south of 45° North will become unsuitable for at least two of the three focal species on both the Northwest- and Northeast-Atlantic coasts by 2200. If these foundational species are unable to adapt to the rising temperatures, they will lose their centers of genetic diversity and their loss will trigger an unpredictable shift in the North-Atlantic intertidal ecosystem.

  20. Managing marine disease emergencies in an era of rapid change

    PubMed Central

    Maynard, Jeffrey; Breyta, Rachel; Carnegie, Ryan B.; Dobson, Andy; Friedman, Carolyn S.; Froelich, Brett; Garren, Melissa; Gulland, Frances M. D.; Heron, Scott F.; Noble, Rachel T.; Revie, Crawford W.; Shields, Jeffrey D.; Vanderstichel, Raphaël; Weil, Ernesto; Wyllie-Echeverria, Sandy; Harvell, C. Drew

    2016-01-01

    Infectious marine diseases can decimate populations and are increasing among some taxa due to global change and our increasing reliance on marine environments. Marine diseases become emergencies when significant ecological, economic or social impacts occur. We can prepare for and manage these emergencies through improved surveillance, and the development and iterative refinement of approaches to mitigate disease and its impacts. Improving surveillance requires fast, accurate diagnoses, forecasting disease risk and real-time monitoring of disease-promoting environmental conditions. Diversifying impact mitigation involves increasing host resilience to disease, reducing pathogen abundance and managing environmental factors that facilitate disease. Disease surveillance and mitigation can be adaptive if informed by research advances and catalysed by communication among observers, researchers and decision-makers using information-sharing platforms. Recent increases in the awareness of the threats posed by marine diseases may lead to policy frameworks that facilitate the responses and management that marine disease emergencies require. PMID:26880835

  1. Managing marine disease emergencies in an era of rapid change.

    PubMed

    Groner, Maya L; Maynard, Jeffrey; Breyta, Rachel; Carnegie, Ryan B; Dobson, Andy; Friedman, Carolyn S; Froelich, Brett; Garren, Melissa; Gulland, Frances M D; Heron, Scott F; Noble, Rachel T; Revie, Crawford W; Shields, Jeffrey D; Vanderstichel, Raphaël; Weil, Ernesto; Wyllie-Echeverria, Sandy; Harvell, C Drew

    2016-03-05

    Infectious marine diseases can decimate populations and are increasing among some taxa due to global change and our increasing reliance on marine environments. Marine diseases become emergencies when significant ecological, economic or social impacts occur. We can prepare for and manage these emergencies through improved surveillance, and the development and iterative refinement of approaches to mitigate disease and its impacts. Improving surveillance requires fast, accurate diagnoses, forecasting disease risk and real-time monitoring of disease-promoting environmental conditions. Diversifying impact mitigation involves increasing host resilience to disease, reducing pathogen abundance and managing environmental factors that facilitate disease. Disease surveillance and mitigation can be adaptive if informed by research advances and catalysed by communication among observers, researchers and decision-makers using information-sharing platforms. Recent increases in the awareness of the threats posed by marine diseases may lead to policy frameworks that facilitate the responses and management that marine disease emergencies require.

  2. Northern Rockies Ecoregion: Chapter 7 in Status and trends of land change in the Western United States--1973 to 2000

    USGS Publications Warehouse

    Taylor, Janis L.

    2012-01-01

    The Northern Rockies Ecoregion (Omernik, 1987; U.S. Environmental Protection Agency, 1997) covers approximately 162,746 km2 (63,200 mi2), primarily in Idaho but also including areas in western Montana and northeastern Washington (fig. 1). Canada forms the northern border of the ecoregion. To the west it is bordered by the Columbia Plateau and Blue Mountains Ecoregions, to the south by the Snake River Basin Ecoregion, and to the east by the Canadian Rockies, Middle Rockies, Northwestern Great Plains, and Northwestern Glaciated Plains Ecoregions; also to the east, the Northern Rockies Ecoregion interfingers with the Montana Valley and Foothill Prairies Ecoregion, each enclosing some isolated areas of the other (fig. 1). The ecoregion is composed of a series of high, rugged mountain ranges, mostly oriented northwest-southeast, with intermontane valleys between them (fig. 2). The entire ecoregion was glaciated during the Pleistocene (1,800,000 to 11,400 years ago), and today numerous large lakes occupy basins formed by glacial action (Omernik, 1987; Habeck and Mutch, 1973). Streams draining these mountain ranges provide a water source for many western cities and towns (fig. 3). The Continental Divide, located at the highest elevations along the northern Rocky Mountains, separates rivers that flow westward into the Columbia River watershed from those that flow eastward into the Missouri River watershed.

  3. Resilience of marine turtle regional management units to climate change.

    PubMed

    Fuentes, Mariana M P B; Pike, David A; Dimatteo, Andrew; Wallace, Bryan P

    2013-05-01

    Enhancing species resilience to changing environmental conditions is often suggested as a climate change adaptation strategy. To effectively achieve this, it is necessary first to understand the factors that determine species resilience, and their relative importance in shaping the ability of species to adjust to the complexities of environmental change. This is an extremely challenging task because it requires comprehensive information on species traits. We explored the resilience of 58 marine turtle regional management units (RMUs) to climate change, encompassing all seven species of marine turtles worldwide. We used expert opinion from the IUCN-SSC Marine Turtle Specialist Group (n = 33 respondents) to develop a Resilience Index, which considered qualitative characteristics of each RMU (relative population size, rookery vulnerability, and genetic diversity) and non climate-related threats (fisheries, take, coastal development, and pollution/pathogens). Our expert panel perceived rookery vulnerability (the likelihood of functional rookeries becoming extirpated) and non climate-related threats as having the greatest influence on resilience of RMUs to climate change. We identified the world's 13 least resilient marine turtle RMUs to climate change, which are distributed within all three major ocean basins and include six of the world's seven species of marine turtle. Our study provides the first look at inter- and intra-species variation in resilience to climate change and highlights the need to devise metrics that measure resilience directly. We suggest that this approach can be widely used to help prioritize future actions that increase species resilience to climate change.

  4. Response of a rocky intertidal ecosystem engineer and community dominant to climate change.

    PubMed

    Menge, Bruce A; Chan, Francis; Lubchenco, Jane

    2008-02-01

    To evaluate how climate change might impact a competitively dominant ecological engineer, we analysed the growth response of the mussel Mytilus californianus to climate patterns [El Niño-Southern Oscillation, Pacific Decadal Oscillation (PDO)]. Mussels grew faster during warmer climatic events. Growth was initially faster on a more productive cape compared to a less productive cape. Growth rates at the two capes merged in 2002, coincidentally with a several year-long shift from warm to cool PDO conditions. To determine the mechanism underlying this response, we examined growth responses to intertidal sea and air temperatures, phytoplankton, sea level and tide height. Together, water temperature (32%) and food (12.5%) explained 44.5% of the variance in mussel growth; contributions of other factors were not significant. In turn, water temperature and food respond to climate-driven variation in upwelling and other, unknown factors. Understanding responses of ecosystem engineers to climate change will require knowing direct thermal effects and indirect effects of factors altered by temperature change.

  5. 77 FR 14959 - Special Local Regulation for Marine Event; Temporary Change of Dates for Recurring Marine Events...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-14

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation for Marine Event; Temporary Change of Dates for Recurring Marine Events in the Fifth Coast Guard District AGENCY: Coast Guard, DHS... changing the enforcement periods of special local regulations for recurring marine events in the...

  6. 76 FR 55558 - Special Local Regulation for Marine Events; Temporary Change of Dates for Recurring Marine Events...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-08

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation for Marine Events; Temporary Change of Dates for Recurring Marine Events in the Fifth Coast Guard District, John H. Kerr Reservoir... temporarily change the enforcement period of special local regulations for one recurring marine event in...

  7. Linking disturbance and resistance to invasion via changes in biodiversity: a conceptual model and an experimental test on rocky reefs.

    PubMed

    Bulleri, Fabio; Benedetti-Cecchi, Lisandro; Jaklin, Andrej; Iveša, Ljiljana

    2016-04-01

    Biological invasions threaten biodiversity worldwide. Nonetheless, a unified theory linking disturbance and resistance to invasion through a mechanistic understanding of the changes caused to biodiversity is elusive. Building on different forms of the disturbance-biodiversity relationship and on the Biotic Resistance Hypothesis (BRH), we constructed conceptual models showing that, according to the main biodiversity mechanism generating invasion resistance (complementary vs. identity effects), disturbance can either promote or hinder invasion. Following the Intermediate Disturbance Hypothesis (IDH), moderate levels of disturbance (either frequency or intensity) are expected to enhance species richness. This will promote invasion resistance when complementarity is more important than species identity. Negative effects of severe disturbance on invasion resistance, due to reductions in species richness, can be either overcompensated or exacerbated by species identity effects, depending on the life-traits becoming dominant within the native species pool. Different invasion resistance scenarios are generated when the diversity-disturbance relationship is negative or positive monotonic. Predictions from these models were experimentally tested on rocky reefs. Macroalgal canopies differing in species richness (1 vs. 2 vs. 3) and identity, were exposed to either a moderate or a severe pulse disturbance. The effects of different canopy-forming species on the seaweed, Caulerpa cylindracea, varied from positive (Cystoseira crinita) to neutral (Cystoseira barbata) to negative (Cystoseira compressa). After 2 years, severely disturbed plots were monopolized by C. compressa and supported less C. cylindracea. Our study shows that the effects of disturbance on invasion depend upon its intensity, the main mechanism through which biodiversity generates invasion resistance and the life-traits selected within the native species pool. Disturbance can sustain invasion resistance when

  8. Extrinsic regime shifts drive abrupt changes in regeneration dynamics at upper treeline in the Rocky Mountains, U.S.A.

    PubMed

    Elliott, Grant P

    2012-07-01

    Given the widespread and often dramatic influence of climate change on terrestrial ecosystems, it is increasingly common for abrupt threshold changes to occur, yet explicitly testing for climate and ecological regime shifts is lacking in climatically sensitive upper treeline ecotones. In this study, quantitative evidence based on empirical data is provided to support the key role of extrinsic, climate-induced thresholds in governing the spatial and temporal patterns of tree establishment in these high-elevation environments. Dendroecological techniques were used to reconstruct a 420-year history of regeneration dynamics within upper treeline ecotones along a latitudinal gradient (approximately 44-35 degrees N) in the Rocky Mountains. Correlation analysis was used to assess the possible influence of minimum and maximum temperature indices and cool-season (November-April) precipitation on regional age-structure data. Regime-shift analysis was used to detect thresholds in tree establishment during the entire period of record (1580-2000), temperature variables significantly Correlated with establishment during the 20th century, and cool-season precipitation. Tree establishment was significantly correlated with minimum temperature during the spring (March-May) and cool season. Regime-shift analysis identified an abrupt increase in regional tree establishment in 1950 (1950-1954 age class). Coincident with this period was a shift toward reduced cool-season precipitation. The alignment of these climate conditions apparently triggered an abrupt increase in establishment that was unprecedented during the period of record. Two main findings emerge from this research that underscore the critical role of climate in governing regeneration dynamics within upper treeline ecotones. (1) Regional climate variability is capable of exceeding bioclimatic thresholds, thereby initiating synchronous and abrupt changes in the spatial and temporal patterns of tree establishment at broad

  9. Southern Rockies Ecoregion: Chapter 8 in Status and trends of land change in the Western United States--1973 to 2000

    USGS Publications Warehouse

    Drummond, Mark A.

    2012-01-01

    The Southern Rockies Ecoregion is a high-elevation mountainous ecoregion that covers approximately 138,854 km2 (53,612 mi2), including much of central Colorado and parts of southern Wyoming and northern New Mexico (fig. 1) (Omernik, 1987; U.S. Environmental Protection Agency, 1997). It abuts six other ecoregions: the Wyoming Basin and Colorado Plateaus Ecoregions on the north and west, the Arizona/New Mexico Plateau Ecoregion on the south, and the Northwestern Great Plains, Western High Plains, and Southwestern Tablelands Ecoregions on the east (fig. 1). The ecoregion receives most of its annual precipitation (25–100 cm) as snowfall, which provides a significant amount of high-elevation snowpack that is an important water source for surrounding ecoregions. The Southern Rockies Ecoregion has a steep elevation gradient from low foothills to high peaks, with several hundred summits higher than 3,660 m (12,000 ft). As a southern extension of the larger RockyMountain system, it is composed primarily of seven main north-south trending mountain ranges that are separated by four large intermontane basins. A fifth basin, the San Luis Valley, is outside the ecoregion, forming a northern finger of the Arizona/New Mexico Plateau Ecoregion that lies mostly to the south. To the east, late Tertiary sand and gravel deposits that were eroded from the relatively young Rocky Mountains were carried eastward by streams, forming the nearby Western High Plains Ecoregion and its underlying Ogallala aquifer.

  10. Effects of climate change on Arctic marine mammal health.

    PubMed

    Burek, Kathy A; Gulland, Frances M D; O'Hara, Todd M

    2008-03-01

    The lack of integrated long-term data on health, diseases, and toxicant effects in Arctic marine mammals severely limits our ability to predict the effects of climate change on marine mammal health. The overall health of an individual animal is the result of complex interactions among immune status, body condition, pathogens and their pathogenicity, toxicant exposure, and the various environmental conditions that interact with these factors. Climate change could affect these interactions in several ways. There may be direct effects of loss of the sea ice habitat, elevations of water and air temperature, and increased occurrence of severe weather. Some of the indirect effects of climate change on animal health will likely include alterations in pathogen transmission due to a variety of factors, effects on body condition due to shifts in the prey base/food web, changes in toxicant exposures, and factors associated with increased human habitation in the Arctic (e.g., chemical and pathogen pollution in the runoff due to human and domestic-animal wastes and chemicals and increased ship traffic with the attendant increased risks of ship strike, oil spills, ballast pollution, and possibly acoustic injury). The extent to which climate change will impact marine mammal health will also vary among species, with some species more sensitive to these factors than others. Baseline data on marine mammal health parameters along with matched data on the population and climate change trends are needed to document these changes.

  11. Rocky Mountain spotted fever

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/000654.htm Rocky Mountain spotted fever To use the sharing features on this page, please enable JavaScript. Rocky Mountain spotted fever is a disease caused by a type of ...

  12. 75 FR 33502 - Special Local Regulation for Marine Events; Temporary Change of Dates for Recurring Marine Events...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-14

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation for Marine Events; Temporary Change of Dates for Recurring Marine Events in the Fifth Coast Guard District AGENCY: Coast Guard, DHS... special local regulations for a recurring marine event in the Fifth Coast Guard District....

  13. 75 FR 17103 - Special Local Regulation for Marine Event; Temporary Change of Dates for Recurring Marine Event...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-05

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation for Marine Event; Temporary Change of Dates for Recurring Marine Event in the Fifth Coast Guard District AGENCY: Coast Guard, DHS... enforcement period of special local regulations for recurring marine event in the Fifth Coast Guard...

  14. 76 FR 1564 - Special Local Regulation for Marine Event; Temporary Change of Dates for Recurring Marine Event...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-11

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation for Marine Event; Temporary Change of Dates for Recurring Marine Event in the Fifth Coast Guard District AGENCY: Coast Guard, DHS... enforcement periods of special local regulations for recurring marine events in the Fifth Coast Guard...

  15. 75 FR 29886 - Special Local Regulation for Marine Events; Temporary Change of Dates for Recurring Marine Events...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-28

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation for Marine Events; Temporary Change of Dates for Recurring Marine Events in the Fifth Coast Guard District AGENCY: Coast Guard, DHS... special local regulations for recurring marine events in the Fifth Coast Guard District. These...

  16. 76 FR 13884 - Special Local Regulation for Marine Event; Temporary Change of Dates for Recurring Marine Event...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-15

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation for Marine Event; Temporary Change of Dates for Recurring Marine Event in the Fifth Coast Guard District AGENCY: Coast Guard, DHS... special local regulations for a recurring marine event in the Fifth Coast Guard District....

  17. 75 FR 17099 - Special Local Regulation for Marine Event; Temporary Change of Dates for Recurring Marine Event...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-05

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation for Marine Event; Temporary Change of Dates for Recurring Marine Event in Fifth Coast Guard District AGENCY: Coast Guard, DHS. ACTION... period of special local regulations for recurring marine events in Fifth Coast Guard District....

  18. 76 FR 36308 - Special Local Regulation for Marine Events; Temporary Change of dates for Recurring Marine Events...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-22

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation for Marine Events; Temporary Change of dates for Recurring Marine Events in the Fifth Coast Guard District; Mill Creek, Hampton, VA... the enforcement period of one special local regulation for recurring marine events in the Fifth...

  19. 75 FR 20294 - Special Local Regulation for Marine Events; Temporary Change of Dates for Recurring Marine Events...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-19

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation for Marine Events; Temporary Change of Dates for Recurring Marine Events in the Fifth Coast Guard District AGENCY: Coast Guard, DHS... period of special local regulations for recurring marine events in the Fifth Coast Guard District....

  20. 77 FR 25070 - Special Local Regulation for Marine Events; Temporary Change of Dates for Recurring Marine Events...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-27

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation for Marine Events; Temporary Change of Dates for Recurring Marine Events in the Fifth Coast Guard District, Ocean City Maryland... recurring marine event in the Fifth Coast Guard District, specifically, the ``Ocean City Maryland...

  1. Rocky road in the Rockies: Challenges to biodiversity

    USGS Publications Warehouse

    Tomback, Diana F.; Kendall, Katherine C.

    2002-01-01

    To people worldwide, the Rocky Mountains of the United States and Canada represent a last bastion of nature in its purest and rawest form-unspoiled forests teeming with elk and deer stalked by mountain lions and grizzly bears; bald eagles nesting near lakes and rivers; fat, feisty native trout in rushing mountain streams; and dazzling arrays of wildflowers in lush meadows. In fact, the total biodiversity of the Rocky Mountains is considerable, with relatively high diversity in birds, mammals, butterflies, reptiles, and conifers (Ricketts et al. 1999) and with geographic variation in the flora and fauna of alpine, forest, foothill, and adjacent shortgrass prairie and shrub communities over more than 20 degrees of latitude and more than 10' of longitude. Although the biodiversity of most North American regions has declined because of anthropogenic influences, the perception remains that the biodiversity of the Rocky Mountains is intact. This view exists in part because the Rocky Mountains are remote from urban centers, in part because so much of the land comprises protected areas such as national parks and wilderness areas, and in part because of wishful thinking-that nothing bad could happen to the biodiversity that is so much a part of the history, national self-image, legends, nature films, and movies of the United States and Canada. Despite modern technology and the homogenization and globalization of their cities and towns, at heart North Americans still regard their land as the New World, with pristine nature and untamed landscapes epitomized by the Rockies. The reality is that the biodiversity of the Rocky Mountains has not been free of anthropogenic influences since the West was settled in the 1800s, and in fact it was altered by Native Americans for centuries prior to settlement. A number of escalating problems and consequences of management choices are currently changing Rocky Mountain ecological communities at a dizzying pace. In Order to maintain some

  2. Sea Changes. Topics in Marine Earth Science.

    ERIC Educational Resources Information Center

    Awkerman, Gary L.

    This publication is designed for use in standard science curricula to develop oceanologic manifestations of certain science topics. Included are teacher guides, student activities, and demonstrations designed to impart ocean science understanding to high school students. The principal theme of Changes in the Sea is presented in this particular…

  3. Compound-specific stable isotopes of organic compounds from lake sediments track recent environmental changes in an alpine ecosystem, Rocky Mountain National Park, Colorado

    USGS Publications Warehouse

    Enders, S.K.; Pagani, M.; Pantoja, S.; Baron, J.S.; Wolfe, A.P.; Pedentchouk, N.; Nunez, L.

    2008-01-01

    Compound-specific nitrogen, carbon, and hydrogen isotope records from sediments of Sky Pond, an alpine lake in Rocky Mountain National Park (Colorado, United States of America), were used to evaluate factors contributing to changes in diatom assemblages and bulk organic nitrogen isotope records identified in lake sediments across Colorado, Wyoming, and southern Montana. Nitrogen isotopic records of purified algal chlorins indicate a substantial shift in nitrogen cycling in the region over the past ???60 yr. Temporal changes in the growth characteristics of algae, captured in carbon isotope records in and around Sky Pond, as well as a -60??? excursion in the hydrogen isotope composition of algal-derived palmitic acid, are coincident with changes in nitrogen cycling. The confluence of these trends is attributed to an increase in biologically available nitrogenous compounds caused by an expansion of anthropogenic influences and temporal changes in catchment hydrology and nutrient delivery associated with meltwater dynamics. ?? 2008, by the American Society of Limnology and Oceanography, Inc.

  4. Changes in Fish Assemblages following the Establishment of a Network of No-Take Marine Reserves and Partially-Protected Areas

    PubMed Central

    Kelaher, Brendan P.; Coleman, Melinda A.; Broad, Allison; Rees, Matthew J.; Jordan, Alan; Davis, Andrew R.

    2014-01-01

    Networks of no-take marine reserves and partially-protected areas (with limited fishing) are being increasingly promoted as a means of conserving biodiversity. We examined changes in fish assemblages across a network of marine reserves and two different types of partially-protected areas within a marine park over the first 5 years of its establishment. We used Baited Remote Underwater Video (BRUV) to quantify fish communities on rocky reefs at 20–40 m depth between 2008–2011. Each year, we sampled 12 sites in 6 no-take marine reserves and 12 sites in two types of partially-protected areas with contrasting levels of protection (n = 4 BRUV stations per site). Fish abundances were 38% greater across the network of marine reserves compared to the partially-protected areas, although not all individual reserves performed equally. Compliance actions were positively associated with marine reserve responses, while reserve size had no apparent relationship with reserve performance after 5 years. The richness and abundance of fishes did not consistently differ between the two types of partially-protected areas. There was, therefore, no evidence that the more regulated partially-protected areas had additional conservation benefits for reef fish assemblages. Overall, our results demonstrate conservation benefits to fish assemblages from a newly established network of temperate marine reserves. They also show that ecological monitoring can contribute to adaptive management of newly established marine reserve networks, but the extent of this contribution is limited by the rate of change in marine communities in response to protection. PMID:24454934

  5. Marine water quality under climate change conditions/scenarios

    NASA Astrophysics Data System (ADS)

    Rizzi, Jonathan; Torresan, Silvia; Critto, Andrea; Zabeo, Alex; Brigolin, Daniele; Carniel, Sandro; Pastres, Roberto; Marcomini, Antonio

    2016-04-01

    The increase of sea temperature and the changes in marine currents are generating impacts on coastal waters such as changes in water biogeochemical and physical parameters (e.g. primary production, pH, salinity) leading to progressive degradation of the marine environment. With the main aim of analysing the potential impacts of climate change on coastal water quality, a Regional Risk Assessment (RRA) methodology was developed and applied to coastal marine waters of the North Adriatic (i.e. coastal water bodies of the Veneto and Friuli Venezia Giulia regions, Italy). RRA integrates the outputs of regional models providing information on macronutrients (i.e. dissolved inorganic nitrogen e reactive phosphorus), dissolved oxygen, pH, salinity and temperature, etc., under future climate change scenarios with site-specific environmental and socio-economic indicators (e.g. biotic index, presence and extension of seagrasses, presence of aquaculture). The presented approach uses Geographic Information Systems to manage, analyse, and visualize data and employs Multi-Criteria Decision Analysis for the integration of stakeholders preferences and experts judgments into the evaluation process. RRA outputs are hazard, exposure, vulnerability, risk and damage maps useful for the identification and prioritization of hot-spot areas and vulnerable targets in the considered region. Therefore, the main aim of this contribution is to apply the RRA methodology to integrate, visualize, and rank according to spatial distribution, physical and chemical data concerning the coastal waters of the North Adriatic Sea in order to predict possible changes of the actual water quality.

  6. Climate change and tropical marine agriculture.

    PubMed

    Crabbe, M James C

    2009-01-01

    The coral reef ecosystem forms part of a 'seascape' that includes land-based ecosystems such as mangroves and forests, and ideally should form a complete system for conservation and management. Aquaculture, including artisanal fishing for fish and invertebrates, shrimp farming, and seaweed farming, is a major part of the farming and gleaning practices of many tropical communities, particularly on small islands, and depends upon the integrity of the reefs. Climate change is making major impacts on these communities, not least through global warming and high CO(2) concentrations. Corals grow within very narrow limits of temperature, provide livelihoods for millions of people in tropical areas, and are under serious threat from a variety of environmental and climate extremes. Corals survive and grow through a symbiotic relationship with photosynthetic algae: zooxanthellae. Such systems apply highly co-operative regulation to minimize the fluctuation of metabolite concentration profiles in the face of transient perturbations. This review will discuss research on how climate influences reef ecosystems, and how science can lead to conservation actions, with benefits for the human populations reliant on the reefs for their survival.

  7. The impacts of climate change in coastal marine systems.

    PubMed

    Harley, Christopher D G; Randall Hughes, A; Hultgren, Kristin M; Miner, Benjamin G; Sorte, Cascade J B; Thornber, Carol S; Rodriguez, Laura F; Tomanek, Lars; Williams, Susan L

    2006-02-01

    Anthropogenically induced global climate change has profound implications for marine ecosystems and the economic and social systems that depend upon them. The relationship between temperature and individual performance is reasonably well understood, and much climate-related research has focused on potential shifts in distribution and abundance driven directly by temperature. However, recent work has revealed that both abiotic changes and biological responses in the ocean will be substantially more complex. For example, changes in ocean chemistry may be more important than changes in temperature for the performance and survival of many organisms. Ocean circulation, which drives larval transport, will also change, with important consequences for population dynamics. Furthermore, climatic impacts on one or a few 'leverage species' may result in sweeping community-level changes. Finally, synergistic effects between climate and other anthropogenic variables, particularly fishing pressure, will likely exacerbate climate-induced changes. Efforts to manage and conserve living marine systems in the face of climate change will require improvements to the existing predictive framework. Key directions for future research include identifying key demographic transitions that influence population dynamics, predicting changes in the community-level impacts of ecologically dominant species, incorporating populations' ability to evolve (adapt), and understanding the scales over which climate will change and living systems will respond.

  8. Potential impact of climate change on marine dimethyl sulfide emissions

    NASA Astrophysics Data System (ADS)

    Bopp, Laurent; Aumont, Olivier; Belviso, Sauveur; Monfray, Patrick

    2003-02-01

    Dimethyl sulfide (DMS) is a biogenic compound produced in sea-surface water and outgased to the atmosphere. Once in the atmosphere, DMS is a significant source of cloud condensation nuclei in the unpolluted marine atmosphere. It has been postulated that climate may be partly modulated by variations in DMS production through a DMS-cloud condensation nuclei-albedo feedback. We present here a modelled estimation of the response of DMS sea-water concentrations and DMS fluxes to climate change, following previous work on marine DMS modeling (Aumont et al., 2002) and on the global warming impact on marine biology (Bopp et al., 2001). An atmosphere ocean general circulation model (GCM) was coupled to a marine biogeochemical scheme and used without flux correction to simulate climate response to increased greenhouse gases (a 1% increase per year in atmospheric CO2 until it has doubled). The predicted global distribution of DMS at 1 × CO2 compares reasonably well with observations; however, in the high latitudes, very elevated concentrations of DMS due to spring and summer blooms of Phaeocystis can not be reproduced. At 2 × CO2, the model estimates a small increase of global DMS flux to the atmosphere (+2%) but with large spatial heterogeneities (from -15% to +30% for the zonal mean). Mechanisms affecting DMS fluxes are changes in (1) marine biological productivity, (2) relative abundance of phytoplankton species and (3) wind intensity. The mean DMS flux perturbation we simulate represents a small negative feedback on global warming; however, the large regional changes may significantly impact regional temperature and precipitation patterns.

  9. Chapter 2. Vulnerability of marine turtles to climate change.

    PubMed

    Poloczanska, Elvira S; Limpus, Colin J; Hays, Graeme C

    2009-01-01

    Marine turtles are generally viewed as vulnerable to climate change because of the role that temperature plays in the sex determination of embryos, their long life history, long age-to-maturity and their highly migratory nature. Extant species of marine turtles probably arose during the mid-late Jurassic period (180-150 Mya) so have survived past shifts in climate, including glacial periods and warm events and therefore have some capacity for adaptation. The present-day rates of increase of atmospheric greenhouse gas concentrations, and associated temperature changes, are very rapid; the capacity of marine turtles to adapt to this rapid change may be compromised by their relatively long generation times. We consider the evidence and likely consequences of present-day trends of climate change on marine turtles. Impacts are likely to be complex and may be positive as well as negative. For example, rising sea levels and increased storm intensity will negatively impact turtle nesting beaches; however, extreme storms can also lead to coastal accretion. Alteration of wind patterns and ocean currents will have implications for juveniles and adults in the open ocean. Warming temperatures are likely to impact directly all turtle life stages, such as the sex determination of embryos in the nest and growth rates. Warming of 2 degrees C could potentially result in a large shift in sex ratios towards females at many rookeries, although some populations may be resilient to warming if female biases remain within levels where population success is not impaired. Indirectly, climate change is likely to impact turtles through changes in food availability. The highly migratory nature of turtles and their ability to move considerable distances in short periods of time should increase their resilience to climate change. However, any such resilience of marine turtles to climate change is likely to be severely compromised by other anthropogenic influences. Development of coastlines may

  10. Transitional states in marine fisheries: adapting to predicted global change.

    PubMed

    MacNeil, M Aaron; Graham, Nicholas A J; Cinner, Joshua E; Dulvy, Nicholas K; Loring, Philip A; Jennings, Simon; Polunin, Nicholas V C; Fisk, Aaron T; McClanahan, Tim R

    2010-11-27

    Global climate change has the potential to substantially alter the production and community structure of marine fisheries and modify the ongoing impacts of fishing. Fish community composition is already changing in some tropical, temperate and polar ecosystems, where local combinations of warming trends and higher environmental variation anticipate the changes likely to occur more widely over coming decades. Using case studies from the Western Indian Ocean, the North Sea and the Bering Sea, we contextualize the direct and indirect effects of climate change on production and biodiversity and, in turn, on the social and economic aspects of marine fisheries. Climate warming is expected to lead to (i) yield and species losses in tropical reef fisheries, driven primarily by habitat loss; (ii) community turnover in temperate fisheries, owing to the arrival and increasing dominance of warm-water species as well as the reduced dominance and departure of cold-water species; and (iii) increased diversity and yield in Arctic fisheries, arising from invasions of southern species and increased primary production resulting from ice-free summer conditions. How societies deal with such changes will depend largely on their capacity to adapt--to plan and implement effective responses to change--a process heavily influenced by social, economic, political and cultural conditions.

  11. Middle Rockies Ecoregion: Chapter 5 in Status and trends of land change in the Western United States--1973 to 2000

    USGS Publications Warehouse

    Taylor, Janis L.

    2012-01-01

    The Middle Rockies Ecoregion—characterized by steep, high-elevation mountain ranges and intermountain valleys—is a disjunct ecoregion composed of three distinct geographic areas: the Greater Yellowstone area in northwest Wyoming, southwest Montana, and eastern Idaho; the Bighorn Mountains in north-central Wyoming and south-central Montana; and the Black Hills in western South Dakota and eastern Wyoming (Omernik, 1987; U.S. Environmental Protection Agency, 1997). The ecoregion covers approximately 90,160 km2 (34,881 mi2), and its three distinct geographic sections are bordered by several other ecoregions (fig. 1). The Yellowstone section abuts the Montana Valley and Foothill Prairies and the Northern Rockies Ecoregions to the north, the Snake River Basin and the Central Basin and Range Ecoregions to the west, and the Wyoming Basin Ecoregion to the south and east. The Bighorn Mountains section lies between the Wyoming Basin Ecoregion to the west and the Northwestern Great Plains Ecoregion to the east, and it abuts the Montana Valleys and Foothill Prairies Ecoregion to the north. The Black Hills section is entirely surrounded by the Northwestern Great Plains Ecoregion. The Continental Divide crosses the ecoregion from the southeast along the Wind River Range, through Yellowstone National Park, and west along the Montana-Idaho border. On both sides of the divide, topographic relief causes local climate variability, particularly the effects of aspect, exposure to prevailing wind, thermal inversions, and rain-shadow effects, that are reflected in the wide variety of flora and fauna within the ecoregion (Ricketts and others, 1999).

  12. Transitional states in marine fisheries: adapting to predicted global change

    PubMed Central

    MacNeil, M. Aaron; Graham, Nicholas A. J.; Cinner, Joshua E.; Dulvy, Nicholas K.; Loring, Philip A.; Jennings, Simon; Polunin, Nicholas V. C.; Fisk, Aaron T.; McClanahan, Tim R.

    2010-01-01

    Global climate change has the potential to substantially alter the production and community structure of marine fisheries and modify the ongoing impacts of fishing. Fish community composition is already changing in some tropical, temperate and polar ecosystems, where local combinations of warming trends and higher environmental variation anticipate the changes likely to occur more widely over coming decades. Using case studies from the Western Indian Ocean, the North Sea and the Bering Sea, we contextualize the direct and indirect effects of climate change on production and biodiversity and, in turn, on the social and economic aspects of marine fisheries. Climate warming is expected to lead to (i) yield and species losses in tropical reef fisheries, driven primarily by habitat loss; (ii) community turnover in temperate fisheries, owing to the arrival and increasing dominance of warm-water species as well as the reduced dominance and departure of cold-water species; and (iii) increased diversity and yield in Arctic fisheries, arising from invasions of southern species and increased primary production resulting from ice-free summer conditions. How societies deal with such changes will depend largely on their capacity to adapt—to plan and implement effective responses to change—a process heavily influenced by social, economic, political and cultural conditions. PMID:20980322

  13. Simulating environmental changes due to marine hydrokinetic energy installations.

    SciTech Connect

    Jones, Craig A.; James, Scott Carlton; Roberts, Jesse Daniel; Seetho, Eddy

    2010-08-01

    Marine hydrokinetic (MHK) projects will extract energy from ocean currents and tides, thereby altering water velocities and currents in the site's waterway. These hydrodynamics changes can potentially affect the ecosystem, both near the MHK installation and in surrounding (i.e., far field) regions. In both marine and freshwater environments, devices will remove energy (momentum) from the system, potentially altering water quality and sediment dynamics. In estuaries, tidal ranges and residence times could change (either increasing or decreasing depending on system flow properties and where the effects are being measured). Effects will be proportional to the number and size of structures installed, with large MHK projects having the greatest potential effects and requiring the most in-depth analyses. This work implements modification to an existing flow, sediment dynamics, and water-quality code (SNL-EFDC) to qualify, quantify, and visualize the influence of MHK-device momentum/energy extraction at a representative site. New algorithms simulate changes to system fluid dynamics due to removal of momentum and reflect commensurate changes in turbulent kinetic energy and its dissipation rate. A generic model is developed to demonstrate corresponding changes to erosion, sediment dynamics, and water quality. Also, bed-slope effects on sediment erosion and bedload velocity are incorporated to better understand scour potential.

  14. Loss of native rocky reef biodiversity in Australian metropolitan embayments.

    PubMed

    Stuart-Smith, Rick D; Edgar, Graham J; Stuart-Smith, Jemina F; Barrett, Neville S; Fowles, Amelia E; Hill, Nicole A; Cooper, Antonia T; Myers, Andrew P; Oh, Elizabeth S; Pocklington, Jacqui B; Thomson, Russell J

    2015-06-15

    Urbanisation of the coastal zone represents a key threat to marine biodiversity, including rocky reef communities which often possess disproportionate ecological, recreational and commercial importance. The nature and magnitude of local urban impacts on reef biodiversity near three Australian capital cities were quantified using visual census methods. The most impacted reefs in urbanised embayments were consistently characterised by smaller, faster growing species, reduced fish biomass and richness, and reduced mobile invertebrate abundance and richness. Reef faunal distribution varied significantly with heavy metals, local population density, and proximity to city ports, while native fish and invertebrate communities were most depauperate in locations where invasive species were abundant. Our study adds impetus for improved urban planning and pollution management practises, while also highlighting the potential for skilled volunteers to improve the tracking of changes in marine biodiversity values and the effectiveness of management intervention.

  15. 75 FR 24799 - Special Local Regulation for Marine Events; Temporary Change of Dates for Recurring Marine Events...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-06

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation for Marine Events; Temporary Change of Dates for Recurring Marine Events in the Fifth Coast Guard District; Correction ACTION... events in the Fifth Coast Guard District, one on April 17-18, 2010, and one on May 29-30, 2010....

  16. 76 FR 37293 - Special Local Regulation for Marine Events; Temporary Change of Dates for Recurring Marine Events...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-27

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation for Marine Events; Temporary Change of Dates for Recurring Marine Events in the Fifth Coast Guard District, John H. Kerr Reservoir... event in the Fifth Coast Guard District, specifically, the ``Clarksville Hydroplane...

  17. Climate change, marine environments, and the US Endangered species act.

    PubMed

    Seney, Erin E; Rowland, Melanie J; Lowery, Ruth Ann; Griffis, Roger B; McClure, Michelle M

    2013-12-01

    Climate change is expected to be a top driver of global biodiversity loss in the 21st century. It poses new challenges to conserving and managing imperiled species, particularly in marine and estuarine ecosystems. The use of climate-related science in statutorily driven species management, such as under the U.S. Endangered Species Act (ESA), is in its early stages. This article provides an overview of ESA processes, with emphasis on the mandate to the National Marine Fisheries Service (NMFS) to manage listed marine, estuarine, and anadromous species. Although the ESA is specific to the United States, its requirements are broadly relevant to conservation planning. Under the ESA, species, subspecies, and "distinct population segments" may be listed as either endangered or threatened, and taking of most listed species (harassing, harming, pursuing, wounding, killing, or capturing) is prohibited unless specifically authorized via a case-by-case permit process. Government agencies, in addition to avoiding take, must ensure that actions they fund, authorize, or conduct are not likely to jeopardize a listed species' continued existence or adversely affect designated critical habitat. Decisions for which climate change is likely to be a key factor include: determining whether a species should be listed under the ESA, designating critical habitat areas, developing species recovery plans, and predicting whether effects of proposed human activities will be compatible with ESA-listed species' survival and recovery. Scientific analyses that underlie these critical conservation decisions include risk assessment, long-term recovery planning, defining environmental baselines, predicting distribution, and defining appropriate temporal and spatial scales. Although specific guidance is still evolving, it is clear that the unprecedented changes in global ecosystems brought about by climate change necessitate new information and approaches to conservation of imperiled species. El

  18. The impact of climate change on the world's marine ecosystems.

    PubMed

    Hoegh-Guldberg, Ove; Bruno, John F

    2010-06-18

    Marine ecosystems are centrally important to the biology of the planet, yet a comprehensive understanding of how anthropogenic climate change is affecting them has been poorly developed. Recent studies indicate that rapidly rising greenhouse gas concentrations are driving ocean systems toward conditions not seen for millions of years, with an associated risk of fundamental and irreversible ecological transformation. The impacts of anthropogenic climate change so far include decreased ocean productivity, altered food web dynamics, reduced abundance of habitat-forming species, shifting species distributions, and a greater incidence of disease. Although there is considerable uncertainty about the spatial and temporal details, climate change is clearly and fundamentally altering ocean ecosystems. Further change will continue to create enormous challenges and costs for societies worldwide, particularly those in developing countries.

  19. Assessing and managing stressors in a changing marine environment.

    PubMed

    Chapman, Peter M

    2016-10-16

    We are facing a dynamic future in the face of multiple stressors acting individually and in combination: climate change; habitat change/loss; overfishing; invasive species; harmful algal blooms/eutrophication; and, chemical contaminants. Historic assessment and management approaches will be inadequate for addressing risks from climate change and other stressors. Wicked problems (non-linear, complex, competing risks and benefits, not easily solvable), will become increasingly common. We are facing irreversible changes to our planetary living conditions. Agreed protection goals and considering both the negatives (risks) and the positives (benefits) of all any and all actions are required, as is judicious and appropriate use of the Precautionary Principle. Researchers and managers need to focus on: determining tipping points (alternative stable points); maintaining ecosystem services; and, managing competing ecosystem services. Marine (and other) scientists are urged to focus their research on wicked problems to allow for informed decision-making on a planetary basis.

  20. Climate change and Southern Ocean ecosystems I: how changes in physical habitats directly affect marine biota.

    PubMed

    Constable, Andrew J; Melbourne-Thomas, Jessica; Corney, Stuart P; Arrigo, Kevin R; Barbraud, Christophe; Barnes, David K A; Bindoff, Nathaniel L; Boyd, Philip W; Brandt, Angelika; Costa, Daniel P; Davidson, Andrew T; Ducklow, Hugh W; Emmerson, Louise; Fukuchi, Mitsuo; Gutt, Julian; Hindell, Mark A; Hofmann, Eileen E; Hosie, Graham W; Iida, Takahiro; Jacob, Sarah; Johnston, Nadine M; Kawaguchi, So; Kokubun, Nobuo; Koubbi, Philippe; Lea, Mary-Anne; Makhado, Azwianewi; Massom, Rob A; Meiners, Klaus; Meredith, Michael P; Murphy, Eugene J; Nicol, Stephen; Reid, Keith; Richerson, Kate; Riddle, Martin J; Rintoul, Stephen R; Smith, Walker O; Southwell, Colin; Stark, Jonathon S; Sumner, Michael; Swadling, Kerrie M; Takahashi, Kunio T; Trathan, Phil N; Welsford, Dirk C; Weimerskirch, Henri; Westwood, Karen J; Wienecke, Barbara C; Wolf-Gladrow, Dieter; Wright, Simon W; Xavier, Jose C; Ziegler, Philippe

    2014-10-01

    Antarctic and Southern Ocean (ASO) marine ecosystems have been changing for at least the last 30 years, including in response to increasing ocean temperatures and changes in the extent and seasonality of sea ice; the magnitude and direction of these changes differ between regions around Antarctica that could see populations of the same species changing differently in different regions. This article reviews current and expected changes in ASO physical habitats in response to climate change. It then reviews how these changes may impact the autecology of marine biota of this polar region: microbes, zooplankton, salps, Antarctic krill, fish, cephalopods, marine mammals, seabirds, and benthos. The general prognosis for ASO marine habitats is for an overall warming and freshening, strengthening of westerly winds, with a potential pole-ward movement of those winds and the frontal systems, and an increase in ocean eddy activity. Many habitat parameters will have regionally specific changes, particularly relating to sea ice characteristics and seasonal dynamics. Lower trophic levels are expected to move south as the ocean conditions in which they are currently found move pole-ward. For Antarctic krill and finfish, the latitudinal breadth of their range will depend on their tolerance of warming oceans and changes to productivity. Ocean acidification is a concern not only for calcifying organisms but also for crustaceans such as Antarctic krill; it is also likely to be the most important change in benthic habitats over the coming century. For marine mammals and birds, the expected changes primarily relate to their flexibility in moving to alternative locations for food and the energetic cost of longer or more complex foraging trips for those that are bound to breeding colonies. Few species are sufficiently well studied to make comprehensive species-specific vulnerability assessments possible. Priorities for future work are discussed.

  1. Conservation of Arctic marine mammals faced with climate change.

    PubMed

    Ragen, Timothy J; Huntington, Henry P; Hovelsrud, Grete K

    2008-03-01

    On a daily basis, societies are making decisions that will influence the effects of climate change for decades or even centuries to come. To promote informed management of the associated risks, we review available conservation measures for Arctic marine mammals, a group that includes some of the most charismatic species on earth. The majority of available conservation measures (e.g., restrictions on hunting, protection of essential habitat areas from development, reduction of incidental take) are intended to address the effects of increasing human activity in the Arctic that are likely to follow decreasing sea ice and rising temperatures. As important as those measures will be in the effort to conserve Arctic marine mammals and ecosystems, they will not address the primary physical manifestations of climate change, such as loss of sea ice. Short of actions to prevent climate change, there are no known conservation measures that can be used to ensure the long-term persistence of these species and ecosystems as we know them today.

  2. 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.

  3. Changes In Snowmelt Timing In Response To Pine Beetle Infestation In Lodgepole Pines In The Colorado Rockies

    NASA Astrophysics Data System (ADS)

    Pugh, E.; Tilton, E. S.

    2008-12-01

    Since 1996, roughly 1.5 million acres of lodgepole pine forest in Colorado have been infested by mountain pine beetles (Dendroctonus ponderosae). We measured physical snowpack properties (depth, density, and temperature) under stands of both living and dead lodgepole pines in the Colorado Rockies. This data allowed us to investigate the effect of increased forest canopy transmittance due to tree death on potential advances in the annual hydrograph. We compared snow accumulation and melt on north-facing and south- facing slopes at an elevation of approximately 3000m. As expected, topography-dominated solar forcing is the chief factor in snowmelt: snow on south-facing slopes melted earlier in the season than north-facing slopes. Comparing stands of dead and live trees within topographic zones revealed a few dramatic differences: snow water equivalent was lower and mean snowpack temperature was warmer in dead lodgepole pine stands. Temperature timeseries from within the snowpack suggest that snow in dead tree stands became isothermal sooner than snow in living tree stands. Together these show that there was indeed earlier snowmelt in lodgepole pine forest regions infested with mountain pine beetle. Earlier snowmelt will likely cause peak snowmelt discharge to occur sooner.

  4. Evidence for abrupt climate changes in annually laminated marine sediments.

    PubMed

    Kemp, Alan E S

    2003-09-15

    Annually laminated sediments from marine or lacustrine settings represent valuable high-resolution archives of climate change that record variation due to changing precipitation and run-off from land or variation in biological productivity and flux in the water column. Because of their annual resolution such sediments may capture abrupt changes of interannual to decadal scales rivaling corals and ice cores in resolution. Laminated sediments often occur intermittently in the sediment column, and the onset and cessation of laminae commonly record the abrupt crossing of thresholds related to climate change, for example, in the degree of oxygenation of bottom waters. Such records from marginal basins and continental margins have been pivotal in demonstrating that abrupt changes hitherto documented only in high-latitude ice cores are synchronous with climatic change at low latitudes. These insights into global teleconnections have improved our understanding of the mechanisms of rapid climate change. In deep-sea settings, the discovery of the episodic occurrence of laminated diatom-rich sediments in the Equatorial Pacific and Southern Ocean provides evidence for massive climate-related biogeochemical excursions tied to abrupt changes in the input, distribution and availability of nutrients in the oceans.

  5. Arctic marine mammals and climate change: impacts and resilience.

    PubMed

    Moore, Sue E; Huntington, Henry P

    2008-03-01

    Evolutionary selection has refined the life histories of seven species (three cetacean [narwhal, beluga, and bowhead whales], three pinniped [walrus, ringed, and bearded seals], and the polar bear) to spatial and temporal domains influenced by the seasonal extremes and variability of sea ice, temperature, and day length that define the Arctic. Recent changes in Arctic climate may challenge the adaptive capability of these species. Nine other species (five cetacean [fin, humpback, minke, gray, and killer whales] and four pinniped [harp, hooded, ribbon, and spotted seals]) seasonally occupy Arctic and subarctic habitats and may be poised to encroach into more northern latitudes and to remain there longer, thereby competing with extant Arctic species. A synthesis of the impacts of climate change on all these species hinges on sea ice, in its role as: (1) platform, (2) marine ecosystem foundation, and (3) barrier to non-ice-adapted marine mammals and human commercial activities. Therefore, impacts are categorized for: (1) ice-obligate species that rely on sea ice platforms, (2) ice-associated species that are adapted to sea ice-dominated ecosystems, and (3) seasonally migrant species for which sea ice can act as a barrier. An assessment of resilience is far more speculative, as any number of scenarios can be envisioned, most of them involving potential trophic cascades and anticipated human perturbations. Here we provide resilience scenarios for the three ice-related species categories relative to four regions defined by projections of sea ice reductions by 2050 and extant shelf oceanography. These resilience scenarios suggest that: (1) some populations of ice-obligate marine mammals will survive in two regions with sea ice refugia, while other stocks may adapt to ice-free coastal habitats, (2) ice-associated species may find suitable feeding opportunities within the two regions with sea ice refugia and, if capable of shifting among available prey, may benefit from

  6. Land-to-sea connectivity: linking human-derived terrestrial subsidies to subtidal habitat change on open rocky coasts.

    PubMed

    Gorman, Daniel; Russell, Bayden D; Connell, Sean D

    2009-07-01

    Spatial subsidies are considered strong where differences in resource availability between donor and recipient systems are greatest. We tested whether human activities on land can increase subsidies of terrigenous nitrogen to open rocky coasts and whether these differences can predict apparent deforestation of kelp forests. We first identified landscape-scale variation in the human-mediated transfer of dissolved inorganic nitrogen (DIN) from natural, agricultural, and urban catchments to temperate coasts after episodes of rainfall. Compared to natural catchments, subsidies of DIN were on average 8-407 times greater in urban catchments, and 1-63 times greater in agricultural catchments. Urban derived nitrogen was attributed to the release of sewage effluent, as delineated by delta15N isotopic values of transplanted algae. Having made this link, we then assessed whether this catchment-scale variation may account for variation in structure of subtidal habitats, particularly as related to theory of nutrient-driven shifts of habitat from perennial (i.e., canopy-forming algae) to opportunistic species (i.e., turf-forming algae). We not only detected patterns consistent with this theory, but also established that the size and total proportion of patches of turf-forming algae were greater where the ratio of donor: recipient nitrogen loads was greater (i.e., size of subsidy). An important realization was that deforestation may be more strongly related to variation in the size of subsidy rather than size of human populations, particularly among urban catchments. These data directly link the type of human activity within catchments to the modification of land-to-sea subsidies and indirectly support theory that predicts terrestrial inputs to have greater ecological effects where the disparity in resource availability between donor and recipient is exacerbated. Our evidence has been used by coastal managers to reconsider their management of coastal systems and has subsequently

  7. Simulating ecological changes caused by marine energy devices

    NASA Astrophysics Data System (ADS)

    Schuchert, Pia; Elsaesser, Bjoern; Pritchard, Daniel; Kregting, Louise

    2015-04-01

    Marine renewable energy from wave and tidal technology has the potential to contribute significantly globally to energy security for future generations. However common to both tidal and wave energy extraction systems is concern regarding the potential environmental consequences of the deployment of the technology as environmental and ecological effects are so far poorly understood. Ecological surveys and studies to investigate the environmental impacts are time consuming and costly and are generally reactive; a more efficient approach is to develop 2 and 3D linked hydrodynamic-ecological modelling which has the potential to be proactive and to allow forecasting of the effects of array installation. The objective of the study was to explore tools which can help model and evaluate possible far- and near field changes in the environment and ecosystem caused by the introduction of arrays of marine energy devices. Using the commercial software, MIKE by DHI, we can predict and model possible changes in the ecosystem. MIKE21 and ECOLab modelling software provide the opportunity to couple high level hydrodynamic models with process based ecological models and/or agent based models (ABM). The flow solutions of the model were determined in an idealised tidal basin with the dimensions similar to that of Strangford Lough, Northern Ireland, a body of water renowned for the location of the first grid-connected tidal turbine, SeaGen. In the first instance a simple process oriented ecological NPZD model was developed which are used to model marine and freshwater systems describing four state variables, Nutrient, Phytoplankton, Zooplankton and Detritus. The ecological model was run and evaluated under two hydrodynamic scenarios of the idealised basin. This included no tidal turbines (control) and an array of 55 turbines, an extreme scenario. Whilst an array of turbines has an effect on the hydrodynamics of the Lough, it is unlikely to see an extreme effect on the NPZD model

  8. Functional consequences of realistic biodiversity changes in a marine ecosystem.

    PubMed

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

    2008-01-22

    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.

  9. Energy budget increases reduce mean streamflow more than snow-rain transitions: using integrated modeling to isolate climate change impacts on Rocky Mountain hydrology

    NASA Astrophysics Data System (ADS)

    Foster, Lauren M.; Bearup, Lindsay A.; Molotch, Noah P.; Brooks, Paul D.; Maxwell, Reed M.

    2016-04-01

    In snow-dominated mountain regions, a warming climate is expected to alter two drivers of hydrology: (1) decrease the fraction of precipitation falling as snow; and (2) increase surface energy available to drive evapotranspiration. This study uses a novel integrated modeling approach to explicitly separate energy budget increases via warming from precipitation phase transitions from snow to rain in two mountain headwaters transects of the central Rocky Mountains. Both phase transitions and energy increases had significant, though unique, impacts on semi-arid mountain hydrology in our simulations. A complete shift in precipitation from snow to rain reduced streamflow between 11% and 18%, while 4 °C of uniform warming reduced streamflow between 19% and 23%, suggesting that changes in energy-driven evaporative loss, between 27% and 29% for these uniform warming scenarios, may be the dominant driver of annual mean streamflow in a warming climate. Phase changes induced a flashier system, making water availability more susceptible to precipitation variability and eliminating the runoff signature characteristic of snowmelt-dominated systems. The impact of a phase change on mean streamflow was reduced as aridity increased from west to east of the continental divide.

  10. Nitrogen and carbon soil dynamics in response to climate change in a high-elevation ecosystem in the Rocky Mountains, U.S.A.

    USGS Publications Warehouse

    Williams, M.W.; Brooks, P.D.; Seastedt, T.

    1998-01-01

    We have implemented a long-term snow-fence experiment at the Niwot Ridge Long-Term Ecological Research (NWT) site in the Colorado Front Range of the Rocky Mountains, U.S.A., to assess the effects of climate change on alpine ecology and biogeochemical cycles. The responses of carbon (C) and nitrogen (N) dynamics in high-elevation mountains to changes in climate are investigated by manipulating the length and duration of snow cover with the 2.6 x 60 m snow fence, providing a proxy for climate change. Results from the first year of operation in 1994 showed that the period of continuous snow cover was increased by 90 d. The deeper and earlier snowpack behind the fence insulated soils from winter air temperatures, resulting in a 9??C increase in annual minimum temperature at the soil surface. The extended period of snow cover resulted in subnivial microbial activity playing a major role in annual C and N cycling. The amount of C mineralized under the snow as measured by CO2 production was 22 g m-2 in 1993 and 35 g m-2 in 1994, accounting for 20% of annual net primary aboveground production before construction of the snow fence in 1993 and 31% after the snow fence was constructed in 1994. In a similar fashion, maximum subnivial N2O flux increased 3-fold behind the snow fence, from 75 ??g N m-2 d-1 in 1993 to 250 ??g N m-2 d-1 in 1994. The amount of N lost from denitrification was greater than the annual atmospheric input of N in snowfall. Surface litter decomposition studies show that there was a significant increase in the litter mass loss under deep and early snow, with no significant change under medium and little snow conditions. Changes in climate that result in differences in snow duration, depth, and extent may therefore produce large changes in the C and N soil dynamics of alpine ecosystems.

  11. Enhanced sediment delivery in a changing climate in semi-arid mountain basins: Implications for water resource management and aquatic habitat in the northern Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Goode, Jaime R.; Luce, Charles H.; Buffington, John M.

    2012-02-01

    The delivery and transport of sediment through mountain rivers affects aquatic habitat and water resource infrastructure. While climate change is widely expected to produce significant changes in hydrology and stream temperature, the effects of climate change on sediment yield have received less attention. In the northern Rocky Mountains, we expect climate change to increase sediment yield primarily through changes in temperature and hydrology that promote vegetation disturbances (i.e., wildfire, insect/pathogen outbreak, drought-related die off). Here, we synthesize existing data from central Idaho to explore (1) how sediment yields are likely to respond to climate change in semi-arid basins influenced by wildfire, (2) the potential consequences for aquatic habitat and water resource infrastructure, and (3) prospects for mitigating sediment yields in forest basins. Recent climate-driven increases in the severity and extent of wildfire suggest that basin-scale sediment yields within the next few years to decades could be greater than the long-term average rate of 146 T km - 2 year - 1 observed for central Idaho. These elevated sediment yields will likely impact downstream reservoirs, which were designed under conditions of historically lower sediment yield. Episodic erosional events (massive debris flows) that dominate post-fire sediment yields are impractical to mitigate, leaving road restoration as the most viable management opportunity for offsetting climate-related increases in sediment yield. However, short-term sediment yields from experimental basins with roads are three orders of magnitude smaller than those from individual fire-related events (on the order of 10 1 T km - 2 year - 1 compared to 10 4 T km - 2 year - 1 , respectively, for similar contributing areas), suggesting that road restoration would provide a relatively minor reduction in sediment loads at the basin-scale. Nevertheless, the ecologically damaging effects of fine sediment (material < 6 mm

  12. Using the Alexander Collection to measure the effects of climate change on the grasshoppers of the southern Rocky Mountains of Colorado

    NASA Astrophysics Data System (ADS)

    Nufio, C. R.; Bowers, D. M.; Guralnick, R. P.

    2007-12-01

    The current study utilizes the recently curated and databased Alexander Grasshopper Collection coupled with a new resurvey program to measure the effects of climate change on grasshoppers found along an elevational gradient in the southern Rocky Mountains of Colorado. The Alexander Collection is composed of approximately 19,000 pinned grasshoppers and a series of field data notebooks from a three year 1958-1960 survey project. During these survey years, Alexander processed over 65,000 grasshoppers from repeatedly sampled sites along an elevational gradient from Boulder (1530 m elev.) to Mt Evans (3900m elev.) in the Colorado Front Range. Data from 2006 shows that at mid-elevation sites grasshoppers are becoming adults 15-28 days earlier than they did nearly a half century ago. We found no changes in the time to reach adulthood at the high elevation sites. Preliminary data from 2007 (a year with milder spring temperatures) suggests that unlike the dramatic patterns documented in 2006, that the time to reach adulthood for grasshoppers at low and high elevation sites was not much different than it was 50 years ago. In 2007, several grasshopper species at mid-elevation did become adults earlier than they had a half century ago.

  13. Differential responses of marine communities to natural and anthropogenic changes

    PubMed Central

    Kowalewski, Michał; Wittmer, Jacalyn M.; Dexter, Troy A.; Amorosi, Alessandro; Scarponi, Daniele

    2015-01-01

    Responses of ecosystems to environmental changes vary greatly across habitats, organisms and observational scales. The Quaternary fossil record of the Po Basin demonstrates that marine communities of the northern Adriatic re-emerged unchanged following the most recent glaciation, which lasted approximately 100 000 years. The Late Pleistocene and Holocene interglacial ecosystems were both dominated by the same species, species turnover rates approximated predictions of resampling models of a homogeneous system, and comparable bathymetric gradients in species composition, sample-level diversity, dominance and specimen abundance were observed in both time intervals. The interglacial Adriatic ecosystems appear to have been impervious to natural climate change either owing to their persistence during those long-term perturbations or their resilient recovery during interglacial phases of climate oscillations. By contrast, present-day communities of the northern Adriatic differ notably from their Holocene counterparts. The recent ecosystem shift stands in contrast to the long-term endurance of interglacial communities in face of climate-driven environmental changes. PMID:25673689

  14. Differential responses of marine communities to natural and anthropogenic changes.

    PubMed

    Kowalewski, Michał; Wittmer, Jacalyn M; Dexter, Troy A; Amorosi, Alessandro; Scarponi, Daniele

    2015-03-22

    Responses of ecosystems to environmental changes vary greatly across habitats, organisms and observational scales. The Quaternary fossil record of the Po Basin demonstrates that marine communities of the northern Adriatic re-emerged unchanged following the most recent glaciation, which lasted approximately 100,000 years. The Late Pleistocene and Holocene interglacial ecosystems were both dominated by the same species, species turnover rates approximated predictions of resampling models of a homogeneous system, and comparable bathymetric gradients in species composition, sample-level diversity, dominance and specimen abundance were observed in both time intervals. The interglacial Adriatic ecosystems appear to have been impervious to natural climate change either owing to their persistence during those long-term perturbations or their resilient recovery during interglacial phases of climate oscillations. By contrast, present-day communities of the northern Adriatic differ notably from their Holocene counterparts. The recent ecosystem shift stands in contrast to the long-term endurance of interglacial communities in face of climate-driven environmental changes.

  15. Interdependency of tropical marine ecosystems in response to climate change

    NASA Astrophysics Data System (ADS)

    Saunders, Megan I.; Leon, Javier X.; Callaghan, David P.; Roelfsema, Chris M.; Hamylton, Sarah; Brown, Christopher J.; Baldock, Tom; Golshani, Aliasghar; Phinn, Stuart R.; Lovelock, Catherine E.; Hoegh-Guldberg, Ove; Woodroffe, Colin D.; Mumby, Peter J.

    2014-08-01

    Ecosystems are linked within landscapes by the physical and biological processes they mediate. In such connected landscapes, the response of one ecosystem to climate change could have profound consequences for neighbouring systems. Here, we report the first quantitative predictions of interdependencies between ecosystems in response to climate change. In shallow tropical marine ecosystems, coral reefs shelter lagoons from incoming waves, allowing seagrass meadows to thrive. Deepening water over coral reefs from sea-level rise results in larger, more energetic waves traversing the reef into the lagoon, potentially generating hostile conditions for seagrass. However, growth of coral reef such that the relative water depth is maintained could mitigate negative effects of sea-level rise on seagrass. Parameterizing physical and biological models for Lizard Island, Great Barrier Reef, Australia, we find negative effects of sea-level rise on seagrass before the middle of this century given reasonable rates of reef growth. Rates of vertical carbonate accretion typical of modern reef flats (up to 3 mm yr-1) will probably be insufficient to maintain suitable conditions for reef lagoon seagrass under moderate to high greenhouse gas emissions scenarios by 2100. Accounting for interdependencies in ecosystem responses to climate change is challenging, but failure to do so results in inaccurate predictions of habitat extent in the future.

  16. The Marine Corps Schools: Driving Institutional Change Towards the Second World War

    DTIC Science & Technology

    2014-05-22

    THE MARINE CORPS SCHOOLS: DRIVING INSTITUTIONAL CHANGE TOWARDS THE SECOND WORLD WAR A Monograph By Major Neil D. Whitney United State Marine...of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering...NUMBER THE MARINE CORPS SCHOOLS: DRIVING INSTITUTIONAL CHANGE TOWARDS THE SECOND WORLD WAR 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6

  17. Cenozoic planktonic marine diatom diversity and correlation to climate change

    USGS Publications Warehouse

    Lazarus, David; Barron, John; Renaudie, Johan; Diver, Patrick; Türke, Andreas

    2014-01-01

    Marine planktonic diatoms export carbon to the deep ocean, playing a key role in the global carbon cycle. Although commonly thought to have diversified over the Cenozoic as global oceans cooled, only two conflicting quantitative reconstructions exist, both from the Neptune deep-sea microfossil occurrences database. Total diversity shows Cenozoic increase but is sample size biased; conventional subsampling shows little net change. We calculate diversity from a separately compiled new diatom species range catalog, and recalculate Neptune subsampled-in-bin diversity using new methods to correct for increasing Cenozoic geographic endemism and decreasing Cenozoic evenness. We find coherent, substantial Cenozoic diversification in both datasets. Many living cold water species, including species important for export productivity, originate only in the latest Miocene or younger. We make a first quantitative comparison of diatom diversity to the global Cenozoic benthic ∂18O (climate) and carbon cycle records (∂13C, and 20-0 Ma pCO2). Warmer climates are strongly correlated with lower diatom diversity (raw: rho = .92, p2 were only moderately higher than today. Diversity is strongly correlated to both ∂13C and pCO2 over the last 15 my (for both: r>.9, detrended r>.6, all p<.001), but only weakly over the earlier Cenozoic, suggesting increasingly strong linkage of diatom and climate evolution in the Neogene. Our results suggest that many living marine planktonic diatom species may be at risk of extinction in future warm oceans, with an unknown but potentially substantial negative impact on the ocean biologic pump and oceanic carbon sequestration. We cannot however extrapolate our my-scale correlations with generic climate proxies to anthropogenic time-scales of warming without additional species-specific information on proximate ecologic controls.

  18. Cenozoic planktonic marine diatom diversity and correlation to climate change.

    PubMed

    Lazarus, David; Barron, John; Renaudie, Johan; Diver, Patrick; Türke, Andreas

    2014-01-01

    Marine planktonic diatoms export carbon to the deep ocean, playing a key role in the global carbon cycle. Although commonly thought to have diversified over the Cenozoic as global oceans cooled, only two conflicting quantitative reconstructions exist, both from the Neptune deep-sea microfossil occurrences database. Total diversity shows Cenozoic increase but is sample size biased; conventional subsampling shows little net change. We calculate diversity from a separately compiled new diatom species range catalog, and recalculate Neptune subsampled-in-bin diversity using new methods to correct for increasing Cenozoic geographic endemism and decreasing Cenozoic evenness. We find coherent, substantial Cenozoic diversification in both datasets. Many living cold water species, including species important for export productivity, originate only in the latest Miocene or younger. We make a first quantitative comparison of diatom diversity to the global Cenozoic benthic ∂(18)O (climate) and carbon cycle records (∂(13)C, and 20-0 Ma pCO2). Warmer climates are strongly correlated with lower diatom diversity (raw: rho = .92, p<.001; detrended, r = .6, p = .01). Diatoms were 20% less diverse in the early late Miocene, when temperatures and pCO2 were only moderately higher than today. Diversity is strongly correlated to both ∂(13)C and pCO2 over the last 15 my (for both: r>.9, detrended r>.6, all p<.001), but only weakly over the earlier Cenozoic, suggesting increasingly strong linkage of diatom and climate evolution in the Neogene. Our results suggest that many living marine planktonic diatom species may be at risk of extinction in future warm oceans, with an unknown but potentially substantial negative impact on the ocean biologic pump and oceanic carbon sequestration. We cannot however extrapolate our my-scale correlations with generic climate proxies to anthropogenic time-scales of warming without additional species-specific information on proximate ecologic

  19. Changing regional emissions of airborne pollutants reflected in the chemistry of snowpacks and wetfall in the Rocky Mountain region, USA, 1993–2012

    USGS Publications Warehouse

    Ingersoll, George P.; Miller, Debra C.; Morris, Kristi H.; McMurray, Jill A.; Port, Garrett M.; Caruso, Brian

    2016-01-01

    Wintertime precipitation sample data from 55 Snowpack sites and 17 National Atmospheric Deposition Program (NADP)/National Trends Network Wetfall sites in the Rocky Mountain region were examined to identify long-term trends in chemical concentration, deposition, and precipitation using Regional and Seasonal Kendall tests. The Natural Resources Conservation Service snow-telemetry (SNOTEL) network provided snow-water-equivalent data from 33 sites located near Snowpack- and NADP Wetfall-sampling sites for further comparisons. Concentration and deposition of ammonium, calcium, nitrate, and sulfate were tested for trends for the period 1993–2012. Precipitation trends were compared between the three monitoring networks for the winter seasons and downward trends were observed for both Snowpack and SNOTEL networks, but not for the NADP Wetfall network. The dry-deposition fraction of total atmospheric deposition, relative to wet deposition, was shown to be considerable in the region. Potential sources of regional airborne pollutant emissions were identified from the U.S. Environmental Protection Agency 2011 National Emissions Inventory, and from long-term emissions data for the period 1996–2013. Changes in the emissions of ammonia, nitrogen oxides, and sulfur dioxide were reflected in significant trends in snowpack and wetfall chemistry. In general, ammonia emissions in the western USA showed a gradual increase over the past decade, while ammonium concentrations and deposition in snowpacks and wetfall showed upward trends. Emissions of nitrogen oxides and sulfur dioxide declined while regional trends in snowpack and wetfall concentrations and deposition of nitrate and sulfate were downward.

  20. Biogeochemical responses of two alpine lakes to climate change and atmospheric deposition, Jasper and Banff National Parks, Canadian Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Hobbs, W.; Vinebrooke, R. D.; Wolfe, A. P.

    2012-12-01

    The sensitivity of remote alpine ecosystems to global change has been documented by 20th century changes in climate, glacial recession, and terrestrial and aquatic ecosystems. In many cases the magnitude and dominance of abiotic drivers on recent changes in alpine lakes is often mediated by processes within the hydrologic catchment. Here we present sedimentary records of biogeochemical responses in two alpine lake ecosystems to multiple environmental drivers over the last ~ 500 years in Banff and Jasper National parks. We combine paleoecological measures of primary production (fossil microbial pigments) and diatom community structure with geochemical proxies of reactive N (Nr) deposition to describe the nature and rate of recent ecosystem changes. Curator Lake in Jasper shows a strong diatom response to the limnological effects of climate warming (e.g. thermal stratification), but little evidence of changes in Nr cycling over the last ~500 years. The response of McConnell Lake in Banff to climate change is strongly mediated by glacial activity within the catchment, and changing inputs of Nr. Our findings highlight the range of limnological responses that may be expressed by similar ecosystems subjected to comparable abiotic stressors, while further documenting the magnitude of the ecological footprint associated with recent environmental change in mountain park environments.

  1. 12. VIEW OF THE ROCKY FLATS PLANT LOOKING WEST. AFTER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. VIEW OF THE ROCKY FLATS PLANT LOOKING WEST. AFTER 38 YEARS, WEAPONS PRODUCTION CEASED IN 1989. IN 1992, THE PLANT MISSION CHANGED FROM WEAPONS PRODUCTION TO ENVIRONMENTAL CLEAN UP AND RESTORATION. BY 1995, THE SITE HAD BEGUN TO BE DISMANTLED (6/27/95). - Rocky Flats Plant, Bounded by Indiana Street & Routes 93, 128 & 72, Golden, Jefferson County, CO

  2. Ocean Tracks: Investigating Marine Migrations in a Changing Ocean

    NASA Astrophysics Data System (ADS)

    Krumhansl, R.; Kochevar, R. E.; Aluwihare, L.; Bardar, E. W.; Hirsch, L.; Hoyle, C.; Krumhansl, K.; Louie, J.; Madura, J.; Mueller-Northcott, J.; Peach, C. L.; Trujillo, A.; Winney, B.; Zetterlind, V.; Busey, A.

    2015-12-01

    The availability of scientific data sets online opens up exciting new opportunities to raise students' understanding of the worlds' oceans and the potential impacts of climate change. The Oceans of Data Institute at EDC; Stanford University; and the Scripps Institution of Oceanography have been collaborating, with the support of three National Science Foundation grants over the past 5 years, to bring marine science data sets into high school and undergraduate classrooms. These efforts have culminated in the development of a web-based student interface to data from the Tagging of Pacific Predators (TOPP) program, NOAA's Global Drifter Program, and NASA Earth-orbiting satellites through a student-friendly Web interface, customized data analysis tools, multimedia supports, and course modules. Ocean Tracks (http://oceantracks.org), which incorporates design principles based on a broad range of research findings in fields such as cognitive science, visual design, mathematics education and learning science, focuses on optimizing students' opportunities to focus their cognitive resources on viewing and comparing data to test hypotheses, while minimizing the time spent on downloading, filtering and creating displays. Ocean Tracks allows students to display the tracks of elephant seals, white sharks, Bluefin tuna, albatross, and drifting buoys along with sea surface temperature, chlorophyll-A, bathymetry, ocean currents, and human impacts overlays. A graphing tool allows students to dynamically display parameters associated with the track such as speed, deepest daily dive and track tortuosity (curviness). These interface features allow students to engage in investigations that mirror those currently being conducted by scientists to understand the broad-scale effects of changes in climate and other human activities on ocean ecosystems. In addition to supporting the teaching of the Ocean and Climate Literacy principles, high school curriculum modules facilitate the teaching

  3. 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.

  4. Predator diversity and density affect levels of predation upon strongly interactive species in temperate rocky reefs.

    PubMed

    Guidetti, Paolo

    2007-12-01

    Indirect effects of predators in the classic trophic cascade theory involve the effects of basal species (e.g. primary producers) mediated by predation upon strongly interactive consumers (e.g. grazers). The diversity and density of predators, and the way in which they interact, determine whether and how the effects of different predators on prey combine. Intraguild predation, for instance, was observed to dampen the effects of predators on prey in many ecosystems. In marine systems, species at high trophic levels are particularly susceptible to extinction (at least functionally). The loss of such species, which is mainly attributed to human activities (mostly fishing), is presently decreasing the diversity of marine predators in many areas of the world. Experimental studies that manipulate predator diversity and investigate the effects of this on strongly interactive consumers (i.e. those potentially capable of causing community-wide effects) in marine systems are scant, especially in the rocky sublittoral. I established an experiment that utilised cage enclosures to test whether the diversity and density of fish predators (two sea breams and two wrasses) would affect predation upon juvenile and adult sea urchins, the most important grazers in Mediterranean sublittoral rocky reefs. Changes in species identity (with sea breams producing major effects) and density of predators affected predation upon sea urchins more than changes in species richness per se. Predation upon adult sea urchins decreased in the presence of multiple predators, probably due to interference competition between sea breams and wrasses. This study suggests that factors that influence both fish predator diversity and density in Mediterranean rocky reefs (e.g. fishing and climate change) may have the potential to affect the predators' ability to control sea urchin population density, with possible repercussions for the whole benthic community structure.

  5. Decadal Changes in the Abundance and Length of Snapper (Chrysophrys auratus) in Subtropical Marine Sanctuaries

    PubMed Central

    Malcolm, Hamish A.; Schultz, Arthur L.; Sachs, Patrick; Johnstone, Nicola; Jordan, Alan

    2015-01-01

    Abundance and length of the highly-targeted snapper Chysophrys auratus were compared between sites in 'no take' areas (Sanctuary Zones: SZ), partial protected areas which are fished (Habitat Protection Zones: HPZ), and areas outside (Outside) the Solitary Islands Marine Park (SIMP), Australia. Baited Remote Underwater Video (BRUV) sampling on shallow rocky reef (15 - 25 m) was conducted annually from 2002 until 2014 in the Austral-winter, covering the decade after these marine park zones were established (2002). Additional deeper sites (25 - 40 m) were sampled in 2010-2011 to assess if findings were more-broadly applicable. Lengths were measured using stereo-BRUVs from 2011-2014. Snapper were significantly more abundant in SZ overall and in most years compared with the other two management types, which did not significantly differ. Snapper rapidly increased after 2 - 3 years protection in all management types, especially SZ. Snapper were present on more SZ deployments than HPZ and Outside after the same period. The positive SZ response in snapper abundance on shallower reef was also found at a broader spatial scale on deeper sites. Again the two fished management types did not show significant differences among each other. There was considerable variation in snapper abundance between years, with strong peaks in 2005, 2009 and 2014 especially in SZ. Abundances remained higher in SZ in the year or two following a strong peak, but decreased to similar abundances to fished areas before the next peak. Snapper length frequency distribution significantly differed between SZ and both fished management types, with more larger snapper within SZ including a higher proportion (58%) that were legal-sized (>25.7 cm FL). HPZ and Outside did not significantly differ from each other, and were dominated by individuals below legal size. Overall, SZ's have positively influenced abundance and length of snapper on these subtropical rocky reefs. PMID:26061036

  6. Climate change influences on marine infectious diseases: implications for management and society

    USGS Publications Warehouse

    Burge, Colleen A.; Eakin, C. Mark; Friedman, Carolyn S.; Froelich, Brett; Hershberger, Paul K.; Hofmann, Eileen E.; Petes, Laura E.; Prager, Katherine C.; Weil, Ernesto; Willis, Bette L.; Ford, Susan E.; Harvell, C. Drew

    2014-01-01

    Infectious diseases are common in marine environments, but the effects of a changing climate on marine pathogens are not well understood. Here, we focus on reviewing current knowledge about how the climate drives hostpathogen interactions and infectious disease outbreaks. Climate-related impacts on marine diseases are being documented in corals, shellfish, finfish, and humans; these impacts are less clearly linked to other organisms. Oceans and people are inextricably linked, and marine diseases can both directly and indirectly affect human health, livelihoods, and well-being. We recommend an adaptive management approach to better increase the resilience of ocean systems vulnerable to marine diseases in a changing climate. Land-based management methods of quarantining, culling, and vaccinating are not successful in the ocean; therefore, forecasting conditions that lead to outbreaks and designing tools/approaches to influence these conditions may be the best way to manage marine disease.

  7. 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.

  8. 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

  9. Climate change influences on marine infectious diseases: implications for management and society.

    PubMed

    Burge, Colleen A; Mark Eakin, C; Friedman, Carolyn S; Froelich, Brett; Hershberger, Paul K; Hofmann, Eileen E; Petes, Laura E; Prager, Katherine C; Weil, Ernesto; Willis, Bette L; Ford, Susan E; Harvell, C Drew

    2014-01-01

    Infectious diseases are common in marine environments, but the effects of a changing climate on marine pathogens are not well understood. Here we review current knowledge about how the climate drives host-pathogen interactions and infectious disease outbreaks. Climate-related impacts on marine diseases are being documented in corals, shellfish, finfish, and humans; these impacts are less clearly linked for other organisms. Oceans and people are inextricably linked, and marine diseases can both directly and indirectly affect human health, livelihoods, and well-being. We recommend an adaptive management approach to better increase the resilience of ocean systems vulnerable to marine diseases in a changing climate. Land-based management methods of quarantining, culling, and vaccinating are not successful in the ocean; therefore, forecasting conditions that lead to outbreaks and designing tools/approaches to influence these conditions may be the best way to manage marine disease.

  10. Interagency collaboration in the Rocky Mountains and Great Plains: Federal-university climate service networks for producing actionable information for climate change adaptation

    NASA Astrophysics Data System (ADS)

    Ray, A. J.; McNie, E.; Averyt, K.; Morisette, J. T.; Derner, J. D.; Ojima, D. S.; Dilling, L.; Barsugli, J. J.

    2014-12-01

    Several federal agencies in north-central United States are each working to develop and disseminate useful climate information to enhance resilience to climate change. This talk will discuss how the U.S. Geological Survey (USGS) the North Central Climate Science Center, the National Oceanic and Atmospheric Administration Western Water Assessment RISA, and the U.S. Department of Agriculture Climate Hub, are building and managing a collaborative research and climate-service network in the Rocky Mountains and Great Plains. This presentation will describe the evolution of the interagency collaboration and the partnership with universities to build a climate service network. Such collaboration takes time and intention and must include the right people and organizations to effectively bridge the gap between use-inspired research and application. In particular, we will discuss a focus on the Upper Missouri Basin, developing research to meet needs in a basin that has had relatively less attention on risks of climate change and adaptation to those risks. Each organization has its own mission, stakeholders, and priorities, but there are many commonalities and potential synergies. Together, these organizations, and their agency scientists and university partners, are fostering cross-agency collaboration at the regional scale to optimize efficient allocation of resources while simultaneously enabling information to be generated at a scale that is relevant to decision makers. By each organization knowing the others needs and priorities, there are opportunities to craft research agendas and strategies for providing services that take advantage of the strengths and skills of the different organizations. University partners are key components of each organization, and of the collaboration, who bring in expertise beyond that in the agencies, in particular connections to social scientists, extension services.

  11. A combined water balance and tree ring approach to understanding the potential hydrologic effects of climate change in the central Rocky Mountain region

    NASA Astrophysics Data System (ADS)

    Gray, Stephen T.; McCabe, Gregory J.

    2010-05-01

    Models suggest that average temperatures in the central Rocky Mountains will increase by >3°C over the next century, while precipitation may remain within late Holocene boundaries. This study investigates the potential hydrologic effects of such warming when combined with the full range of precipitation variability experienced over the past millennium. Using the upper Yellowstone drainage as a test case, a water balance model is constructed to estimate river discharge from precipitation and temperature inputs (r = 0.85 versus observed). The model then was run using tree ring precipitation estimates for 1177-1910 and 1911-1995 A.D. combined with (1) average observed temperatures 1896-1995; (2) reconstructed Northern Hemisphere temperatures since 1177; or (3) Intergovernmental Panel on Climate Change temperature projections for 2025, 2050, and 2100. Discharge estimates generated by driving the model with tree ring precipitation for 1911-1995 and observed temperatures served as a baseline for comparisons with other climate runoff scenarios. All combinations of the various temperature scenarios and pre-1911 precipitation resulted in mean discharge below the gauge period baseline. Projected temperatures for 2050 and 2100 produced the lowest mean discharge at 85% and 76% of baseline, respectively. Combining observed temperatures with the paleoprecipitation scenarios created numerous multidecadal periods with discharge <85% of baseline. Discharge during these same multidecadal droughts declined an additional 16-34% under the 2025-2100 temperature regimes. Likewise inherent multidecadal precipitation variability adds a large degree of nonstationarity to the climate change responses seen in discharge estimates. While this combined tree ring and water balance scenario exercise does not provide precise forecasts for future conditions, these results suggest that a 1°-3°C warming could have major negative effects on water availability in the upper Yellowstone. These results

  12. Climate change and ecosystem disruption: the health impacts of the North American Rocky Mountain pine beetle infestation.

    PubMed

    Embrey, Sally; Remais, Justin V; Hess, Jeremy

    2012-05-01

    In the United States and Canada, pine forest ecosystems are being dramatically affected by an unprecedented pine beetle infestation attributed to climate change. Both decreased frequency of extremely cold days and warmer winter temperature averages have led to an enphytotic devastating millions of acres of pine forest. The associated ecosystem disruption has the potential to cause significant health impacts from a range of exposures, including increased runoff and water turbidity, forest fires, and loss of ecosystem services. We review direct and indirect health impacts and possible prevention strategies. The pine beetle infestation highlights the need for public health to adopt an ecological, systems-oriented view to anticipate the full range of potential health impacts from climate change and facilitate effective planned adaptation.

  13. Climate Change and Ecosystem Disruption: The Health Impacts of the North American Rocky Mountain Pine Beetle Infestation

    PubMed Central

    Remais, Justin V.; Hess, Jeremy

    2012-01-01

    In the United States and Canada, pine forest ecosystems are being dramatically affected by an unprecedented pine beetle infestation attributed to climate change. Both decreased frequency of extremely cold days and warmer winter temperature averages have led to an enphytotic devastating millions of acres of pine forest. The associated ecosystem disruption has the potential to cause significant health impacts from a range of exposures, including increased runoff and water turbidity, forest fires, and loss of ecosystem services. We review direct and indirect health impacts and possible prevention strategies. The pine beetle infestation highlights the need for public health to adopt an ecological, systems-oriented view to anticipate the full range of potential health impacts from climate change and facilitate effective planned adaptation. PMID:22420788

  14. Historians' Rocky Job Market

    ERIC Educational Resources Information Center

    Grafton, Anthony; Townsend, Robert B.

    2008-01-01

    In this article, the authors discuss how the historians' job market is perennially rocky. The history profession had its "golden age" in the 1950s and early 1960s when a generation born in the demographic trench of the Depression entered the market just as the first of the baby boomers began to swell college enrollments. But that moment was…

  15. Rocky Mountain Spotted Fever.

    PubMed

    Phillips, Jennan

    2017-01-01

    The tick-borne disease Rocky Mountain spotted fever (RMSF) can have deadly outcomes unless treated appropriately, yet nonspecific flu-like symptoms complicate diagnosis. Occupational health nurses must have a high index of suspicion with symptomatic workers and recognize that recent recreational or occupational activities with potential tick exposure may suggest RMSF.

  16. Consequences of early snowmelt in Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2013-01-01

    Snow melted significantly earlier in the Rocky Mountains in 2012 than in previous years, with serious consequences for plants and animals, scientists reported at the AGU Fall Meeting. David Inouye of the University of Maryland, College Park, and the Rocky Mountain Biological Laboratory said that "the timing of winter's end is changing." He has been observing snowmelt dates and flowering of plants at a site at 2900 meters altitude. This year's snowmelt occurred 23 April, whereas the previous year, snow melted 19 June, he reported.

  17. Climate change and Elevational Dependence at a Mid-Latitude Mountain System, Niwot Ridge, Colorado Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Williams, M. W.; Kittel, T.; Hartman, M.; Ackerman, T.; Losleben, M.

    2007-12-01

    Mid-latitude mountain systems are critically sensitive to recent and projected climate change under an elevated greenhouse gas world. It is often taken that climatic change at high elevation sites will reflect those at lower sites - regional warming is assumed to be consistently played out in mountains, or even amplified by the snow-albedo feedback. The anticipated outcome is that the alpine will eventually be "pushed off the top of mountains." There are several reasons why this might not be the case, or at least considerably delayed - one is whether high elevation climates reasonably reflect regional lowland trends or if they are decoupled from them as a result of mountain climatic processes. We evaluated standard climatological variables (minimum & maximum temperature, precipitation) and derived variables [diurnal temperature range, growing season length (using both 0° & -3°C thresholds), and growing degree days (0°C base)] from subalpine (C1, 3048m) and high alpine (D1, 3749m) sites from 1953 to 2006 at Niwot Ridge in Colorado, the longest high- elevation climate record in the US. Over the last 54 years, mean maximum temperature (Tmax) increased through much of the year in the subalpine (trend in annual Tmax=+0.4°C/decade), but in the alpine decreased in early winter (-0.4 to -0.6°C/decade). These patterns resulted in altered seasonal cycles for the two sites, but in different ways: a positive offset in the subalpine (C1) and amplification in the alpine. Precipitation increased at the alpine site from October through April (trend in annual ppt=+100mm/decade), but not during any season in the subalpine. At both sites, summer onset is later and termination earlier, so that the "growing season" has shortened - this reflects long-term tendencies in minimum temperatures. An apparent contradiction is that growing degree-days have gone up at the subalpine site; this due to the positive trend in maximum temperatures. The alpine showed no corresponding trend. An

  18. Increasing Carbon Loss from Snow-Scoured Alpine Tundra in the Colorado Rocky Mountains: An Indicator of Climate Change?

    NASA Astrophysics Data System (ADS)

    Knowles, J. F.; Blanken, P.; Williams, M. W.; Lawrence, C. R.

    2015-12-01

    We used the eddy covariance method to continuously measure the net ecosystem exchange of carbon dioxide for seven years from a snow-scoured alpine tundra meadow on Niwot Ridge in Colorado, USA that may be underlain by sporadic permafrost. On average, the alpine tundra was a net annual source of 232 g C m-2 to the atmosphere, and the source strength of this ecosystem increased over the length of the seven year period due to both reduced carbon uptake during the growing season and increased respiration throughout the winter. To constrain the contribution of permafrost degradation to observed carbon emissions, we also measured the radiocarbon content of actively cycling, occluded, and mineral soil carbon pools across a meso-scale soil moisture and (possible) permafrost gradient within this meadow, as well as the seasonal radiocarbon content of soil respiration. These data suggest that wintertime soil respiration is limited to patches of wet meadow tundra that may be associated with permafrost. Furthermore, soil respiration from one of these locations indicates preferential turnover of a relatively slow cycling carbon pool during the winter. Given that summer air temperatures and positive degree days have been increasing on Niwot Ridge since the middle of the 20th century, this research suggests that an alpine tundra permafrost-respiration feedback to climate change, similar to that observed in arctic tundra ecosystems, may be currently underway.

  19. Spatial variation in the potential response of the Rocky Mountain National Park forest tundra ecotone to climatic change

    SciTech Connect

    Baker, W.L.; Weisberg, P.J. |

    1995-06-01

    The current structure of the forest tundra ecotone landscape and its tree populations constrain the potential response of the ecotone to climatic change. Our objectives were to characterize the major kinds of ecotone composition and environment and identify how tree regeneration varies in relation to environment. We analyzed the structure of ecotone landscapes using the r.le GIS programs. In the field, we sampled tree seedling density at 125 stratified random sampling locations. Ecotones vary from short (500 m), low diversity, two zone ecotones (closed forest and tundra) common on southerly facing, moderate, granitic slopes to long (3500 m), high diversity, four zone ecotones with multiple disturbances and permanent features found on till. Seedling densities are currently highest in mesic environments, particularly in patch forest openings and in willow wetlands in the krummholz zone. The environmental factors that influence landscape structure are not the same as those correlated with seedling density, but certain types of ecotone typically contain (or lack) environments with high seedling densities. If current seedlings attain tree height, the patch forest zone in some ecotones will become closed forest.

  20. The rocky road from roots to rice: a review of the changing food and nutrition situation in Papua New Guinea.

    PubMed

    Saweri, W

    2001-01-01

    Although it is not happening uniformly within the country, the adoption of a modern lifestyle by Papua New Guineans is affecting their food habits and choices. More and more people consume rice, tinned fish and tinned meat. In towns and in villages with easy access to urban centres, these food items comprise an ever increasing part of the diet. These dietary changes are leading to increases in the prevalence of chronic lifestyle-related diseases such as obesity, hypertension and coronary heart disease. Although average calorie availability is similar in urban and rural sectors, at around 2600 kilocalories per person per day, the nutritional outcomes are different. This is mainly due to the higher energy density of the modern urban diet with a greater intake of fat and protein. The traditional diet is low in protein with rather high energy content from starchy root crops. Studies have shown that urban children tend to be taller and heavier than their rural counterparts and that the prevalence of overweight and obesity is higher among adults in urban than in rural areas. Finally, across all income groups and geographical regions, more women than men are chronically undernourished.

  1. Transportation Fuels Markets, Midwest and Rocky Mountain

    EIA Publications

    2017-01-01

    A new study commissioned by the U.S. Energy Information Administration (EIA), finds that changes in North American energy markets over the past decade have strengthened the supply of transportation fuels including motor gasoline, distillates, and jet fuel in the Midwest and Rocky Mountain regions.

  2. Can we predict the direction of marine primary production change under global warming?

    NASA Astrophysics Data System (ADS)

    Taucher, J.; Oschlies, A.

    2011-01-01

    A global Earth System model is employed to investigate the role of direct temperature effects in the response of marine ecosystems to climate change. While model configurations with and without consideration of explicit temperature effects can reproduce observed current biogeochemical tracer distributions and estimated carbon export about equally well, carbon flow through the model ecosystem reveals strong temperature sensitivities. Depending on whether biological processes are assumed temperature sensitive or not, simulated marine net primary production (NPP) increases or decreases under projected climate change driven by a business-as-usual CO2 emission scenario for the 21st century. This suggests that indirect temperature effects such as changes in the supply of nutrients and light are not the only relevant factors to be considered when modeling the response of marine ecosystems to climate change. A better understanding of direct temperature effects on marine ecosystems is required before even the direction of change in NPP can be reliably predicted.

  3. Marine gametes in a changing ocean: Impacts of climate change stressors on fecundity and the egg.

    PubMed

    Foo, Shawna A; Byrne, Maria

    2017-02-17

    In marine invertebrates, the environmental history of the mother can influence fecundity and egg size. Acclimation of females in climate change stressors, increased temperature and low pH, results in a decrease in egg number and size in many taxa, with the exception of cephalopods, where eggs increase in size. With respect to spawned eggs, near future levels of ocean acidification can interfere with the egg's block to polyspermy and intracellular pH. Reduction of the extracellular egg jelly coat seen in low pH conditions has implications for impaired egg function and fertilization. Some fast generation species (e.g. copepods, polychaetes) have shown restoration of female reproductive output after several generations in treatments. It will be important to determine if the changes to egg number and size induced by exposure to climate change stressors are heritable.

  4. Visitor impact on rocky shore communities of Qeshm Island, the Persian Gulf, Iran.

    PubMed

    Pour, Fatemeh Aghajan; Shokri, Mohammad Reza; Abtahi, Behrooz

    2013-02-01

    The influence of visitors on macroinvertebrates of rocky intertidal shores was investigated in southern coasts of the Qeshm Island, the Persian Gulf, Iran. Qeshm Island located at the Strait of Hormuz, with an area of 1,491 km(2), is the largest island in the region. This island consists of a number of important natural habitat types including creeks, mangroves, corals, and sandy, muddy, and rocky shores that accommodate diverse marine flora and fauna communities. Two rocky shores were selected at the touristic beaches being visited regularly, and further two control locations selected at pristine shores. Intertidal macroinvertebrates were collected from six microhabitats including rock platforms, cobbles, boulders, crevices, sea walls, and rock pools during two different periods representing high and low tourist seasons. Species richness, density, and assemblage structure in heavily visited shores were compared with that of control locations. Striped barnacles (Balanus amphitrite) were present on platforms of all locations, thus the changes in their size were used as the obvious contrast associated with visitor's impact. A total of 70 macroinvertebrate species from 11 phyla were recorded. Significant differences were detected in taxonomic richness, density, and assemblage structure of macroinvertebrates between heavily visited and pristine shores, suggesting that macroinvertebrates were adversely affected by visitors' impact at heavily visited shores. The test of changes in species richness, density, and assemblage structure from high to low seasons yielded mixed results. The significant changes in density and assemblage structure from high to low seasons were only observed in one heavily visited shore. A significant reduction in size of striped barnacles was observed only in one heavily visited shore. The opportunistic or fugitive species (e.g., small macroalgae and barnacles) were dominant macroinvertebrates on heavily visited shores indicating early succession

  5. Will life find a way? Evolution of marine species under global change.

    PubMed

    Calosi, Piero; De Wit, Pierre; Thor, Peter; Dupont, Sam

    2016-10-01

    Projections of marine biodiversity and implementation of effective actions for its maintenance in the face of current rapid global environmental change are constrained by our limited understanding of species' adaptive responses, including transgenerational plasticity, epigenetics and natural selection. This special issue presents 13 novel studies, which employ experimental and modelling approaches to (i) investigate plastic and evolutionary responses of marine species to major global change drivers; (ii) ask relevant broad eco-evolutionary questions, implementing multiple species and populations studies; (iii) show the advantages of using advanced experimental designs and tools; (iv) construct novel model organisms for marine evolution; (v) help identifying future challenges for the field; and (vi) highlight the importance of incorporating existing evolutionary theory into management solutions for the marine realm. What emerges is that at least some populations of marine species have the ability to adapt to future global change conditions. However, marine organisms' capacity for adaptation appears finite, due to evolutionary trade-offs and possible rapid losses in genetic diversity. This further corroborates the idea that acquiring an evolutionary perspective on how marine life will respond to the selective pressure of future global changes will guide us in better identifying which conservation efforts will be most needed and most effective.

  6. Rocky Mountain spotted fever.

    PubMed

    Lacz, N L; Schwartz, R A; Kapila, R

    2006-04-01

    Rocky Mountain spotted fever (RMSF) is an unusual but important dermatological condition to identify without hesitation. The classic triad of headache, fever, and a rash that begins on the extremities and travels proximally to involve the trunk is found in a majority of patients. The cutaneous centripetal pattern is a result of cell to cell migration by the causative organism Rickettsia rickettsii. Such individuals should receive prompt antimicrobial therapy and supportive care to avoid serious and potentially fatal complications.

  7. Rocky Mountain spotted fever.

    PubMed

    Kamper, C A; Chessman, K H; Phelps, S J

    1988-02-01

    The epidemiology, pathogenesis, clinical features, and treatment of Rocky Mountain spotted fever are reviewed. Rocky Mountain spotted fever is a severe infection caused by Rickettsia rickettsii transmitted to man by various species of ticks. High-incidence areas exist in the southeast and south central United States. Only 60-70% of patients with the disease report a history of tick bite or exposure to tick-infested areas. The disease is initially characterized by fever, headache, gastrointestinal complaints, myalgia, and a generalized rash. In several days generalized vasculitis may lead to periorbital edema and nonpitting edema of the face and extremities. Central nervous system involvement is common. Because signs and symptoms associated with the disease are nonspecific, the diagnosis is often delayed or missed. Traditionally diagnostic confirmation relied on serologic testing, but an indirect fluorescent antibody assay will soon be commercially available. Rocky Mountain spotted fever is usually treated with the rickettsiostatic agents chloramphenicol or tetracycline, but few comparative data on these agents in patients with the disease are available. For patients who cannot tolerate oral medications, intravenous chloramphenicol sodium succinate is the preferred treatment; chloramphenicol is also the drug of choice for children less than eight years of age. Otherwise, oral tetracycline hydrochloride is the drug of choice. Antibiotic therapy should be continued for 7-10 days or until the patient is afebrile for two to five days. All cases of Rocky Mountain spotted fever must be reported to the Centers for Disease Control. The best ways to decrease the morbidity and mortality of the disease are to increase awareness of its signs and symptoms and to prevent exposure to ticks.

  8. Acclimatization and Adaptive Capacity of Marine Species in a Changing Ocean.

    PubMed

    Foo, S A; Byrne, M

    To persist in an ocean changing in temperature, pH and other stressors related to climate change, many marine species will likely need to acclimatize or adapt to avoid extinction. If marine populations possess adequate genetic variation in tolerance to climate change stressors, species might be able to adapt to environmental change. Marine climate change research is moving away from single life stage studies where individuals are directly placed into projected scenarios ('future shock' approach), to focus on the adaptive potential of populations in an ocean that will gradually change over coming decades. This review summarizes studies that consider the adaptive potential of marine invertebrates to climate change stressors and the methods that have been applied to this research, including quantitative genetics, laboratory selection studies and trans- and multigenerational experiments. Phenotypic plasticity is likely to contribute to population persistence providing time for genetic adaptation to occur. Transgenerational and epigenetic effects indicate that the environmental and physiological history of the parents can affect offspring performance. There is a need for long-term, multigenerational experiments to determine the influence of phenotypic plasticity, genetic variation and transgenerational effects on species' capacity to persist in a changing ocean. However, multigenerational studies are only practicable for short generation species. Consideration of multiple morphological and physiological traits, including changes in molecular processes (eg, DNA methylation) and long-term studies that facilitate acclimatization will be essential in making informed predictions of how the seascape and marine communities will be altered by climate change.

  9. Symposium 9: Rocky Mountain futures: preserving, utilizing, and sustaining Rocky Mountain ecosystems

    USGS Publications Warehouse

    Baron, Jill S.; Seastedt, Timothy; Fagre, Daniel B.; Hicke, Jeffrey A.; Tomback, Diana; Garcia, Elizabeth; Bowen, Zachary H.; Logan, Jesse A.

    2013-01-01

    In 2002 we published Rocky Mountain Futures, an Ecological Perspective (Island Press) to examine the cumulative ecological effects of human activity in the Rocky Mountains. We concluded that multiple local activities concerning land use, hydrologic manipulation, and resource extraction have altered ecosystems, although there were examples where the “tyranny of small decisions” worked in a positive way toward more sustainable coupled human/environment interactions. Superimposed on local change was climate change, atmospheric deposition of nitrogen and other pollutants, regional population growth, and some national management policies such as fire suppression.

  10. 3. FIRSTFLOOR LABORATORY. VIEW TO SOUTHWEST. Rocky Mountain Arsenal, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. FIRST-FLOOR LABORATORY. VIEW TO SOUTHWEST. - Rocky Mountain Arsenal, Administration-Laboratory- Change House-Bomb Rail, 420 feet South of December Seventh Avenue; 530 feet West of D Street, Commerce City, Adams County, CO

  11. Climate Change and Genetic Structure of Leading Edge and Rear End Populations in a Northwards Shifting Marine Fish Species, the Corkwing Wrasse (Symphodus melops)

    PubMed Central

    Knutsen, Halvor; Jorde, Per Erik; Gonzalez, Enrique Blanco; Robalo, Joana; Albretsen, Jon; Almada, Vitor

    2013-01-01

    One mechanism by which marine organisms may respond to climate shifts is range shifts. The corkwing wrasse (Symphodus melops) is a temperate fish species, inhabiting the coasts of Europe, that show strong indications of current as well as historical (ice-age) range shifts towards the north. Nine neutral microsatellite DNA markers were screened to study genetic signatures and spatial population structure over the entire geographic and thermal gradient of the species from Portugal to Norway. A major genetic break (FST  = 0.159 average among pairs) was identified between Scandinavian and more southern populations, with a marked reduction (30% or more) in levels of genetic variability in Scandinavia. The break is probably related to bottleneck(s) associated with post-glacial colonization of the Scandinavian coasts, and indicates a lack of present gene flow across the North Sea. The lack of gene flow can most likely be attributed to the species’ need for rocky substrate for nesting and a relatively short pelagic larval phase, limiting dispersal by ocean currents. These findings demonstrate that long-distance dispersal may be severely limited in the corkwing wrasse, and that successful range-shifts following present climate change may be problematic for this and other species with limited dispersal abilities, even in the seemingly continuous marine environment. PMID:23840721

  12. Holocene planform change in broad valleys in the Southern Rocky Mountains: the role of vegetation type and beaver in shaping long-term channel complexity

    NASA Astrophysics Data System (ADS)

    Polvi-Pilgrim, L. E.; Wohl, E.

    2012-04-01

    Over the past decade, researchers have shown the importance of streambank vegetation in forming meandering channels. Recent work has also showed the importance of beaver in creating a more heterogeneous landscape, in terms of channel planform and complexity, sedimentation, and riparian vegetation. Streambank vegetation and beavers interact as ecosystem engineers to determine long-term channel planform, floodplain processes, and complexity. We use studies of Holocene beaver aggradation and effects on channel complexity, in addition to measurements of added bank strength by various riparian vegetation types, to predict Holocene planform change in broad (>200 m, disconnected from hillslopes), high-elevation (>2300 m) valleys of the Colorado Front Range in the Southern Rocky Mountains. Sediment core analyses and shallow subsurface geophysical measurements indicate that post-glacial beaver-related aggradation is significant. Additionally, historical and field evidence from the last century, when the beaver population steadily declined, shows that beaver contribute to the formation of a complex, multi-thread channel network. Streambank vegetation in the Colorado Front Range can be categorized based on its ability to provide added strength to the streambank, where riparian or rhizomatous shrubs and trees provide more strength than xeric trees or non-rhizomatous graminoids and herbs, depending on the bank texture and hydrologic conditions. Assuming a snowmelt-dominated flow regime in a gravel-bed channel system, four planform regimes are identified based on beaver populations and the abundance and presence of xeric or riparian vegetation. Following deglaciation, without beaver or bank-stabilizing vegetation, (1) a braided channel formed. The introduction of riparian vegetation and a more stable flow regime triggered a transition to (2) a meandering channel, which in turn provided habitat for beaver, allowing the formation of (3) a complex multi-thread channel system. The

  13. Seasonal changes in Cyclobalanopsis glauca transpiration and canopy stomatal conductance and their dependence on subterranean water and climatic factors in rocky karst terrain

    NASA Astrophysics Data System (ADS)

    Huang, Yuqing; Li, Xiankun; Zhang, Zhongfeng; He, Chengxin; Zhao, Ping; You, Yeming; Mo, Ling

    2011-05-01

    SummaryThe presence of forest on south China karst is presumed to increase perennial epikarst spring flow, partly because there is adequate storage in bedrock fractures underlying the shallow soil in the forest. If true, transpiration of the ecosystem would not be strongly reduced by temperate drought if trees develop deep roots to reach the perched epikarst water. Therefore, in karst ecosystem the epikarst-soil-plant-atmosphere continuum (ESPAC) would be different from the SPAC in non-karst system. We measured transpiration and canopy conductance from a Cyclobalanopsis glauca (syn. Quercus glauca) stand on a rocky hill slope in South China during 2006-2007 by using the Granier's sap-flow method. Annual stand transpiration (836 mm y -1) accounted for 48.7% of the rainfall during the experimental year. Per month, daily stand transpiration ( E c) maximums varied between 2.1 mm d -1 in January (cool season) to 5.1 mm d -1 in July (hot season). In the driest months, September and October, E c of C. glauca was still high with maximum E c 3.82 mm d -1 and 2.96 mm d -1 respectively. Solar radiation ( PAR), vapor pressure deficiency ( VPD), and air temperature were simple influences on transpiration of C. glauca, which contributed to a quadratic power model, while soil water content ( SWC) moisture influence on transpiration was complicated, which SWC influenced E c greatly under higher VPD, but did not influence E c under low VPD. High stomatal openness occurred in C. glauca in the early morning and declined throughout the day. The relation coefficient between canopy stomatal conductance ( G c) and E c was high when VPD was more than 1.0 kPa, moderate when 0.5 kPa < VPD < 1.0 kPa, and low with VPD of less than 0.5 kPa. Under high VPD, stomatal control of transpiration is high. The pattern of seasonal change of transpiration and canopy stomatal conductance of the plant in karst regions is different from that in non-karst regions, with the stand transpiration and canopy

  14. Ecophysiology. Climate change tightens a metabolic constraint on marine habitats.

    PubMed

    Deutsch, Curtis; Ferrel, Aaron; Seibel, Brad; Pörtner, Hans-Otto; Huey, Raymond B

    2015-06-05

    Warming of the oceans and consequent loss of dissolved oxygen (O2) will alter marine ecosystems, but a mechanistic framework to predict the impact of multiple stressors on viable habitat is lacking. Here, we integrate physiological, climatic, and biogeographic data to calibrate and then map a key metabolic index-the ratio of O2 supply to resting metabolic O2 demand-across geographic ranges of several marine ectotherms. These species differ in thermal and hypoxic tolerances, but their contemporary distributions are all bounded at the equatorward edge by a minimum metabolic index of ~2 to 5, indicative of a critical energetic requirement for organismal activity. The combined effects of warming and O2 loss this century are projected to reduce the upper ocean's metabolic index by ~20% globally and by ~50% in northern high-latitude regions, forcing poleward and vertical contraction of metabolically viable habitats and species ranges.

  15. Climate Change, Coral Reef Ecosystems, and Management Options for Marine Protected Areas

    NASA Astrophysics Data System (ADS)

    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.

  16. 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.

  17. Interactive effects of global climate change and pollution on marine microbes: the way ahead

    PubMed Central

    Coelho, Francisco J R C; Santos, Ana L; Coimbra, Joana; Almeida, Adelaide; Cunha, Ângela; Cleary, Daniel F R; Calado, Ricardo; Gomes, Newton C M

    2013-01-01

    Global climate change has the potential to seriously and adversely affect marine ecosystem functioning. Numerous experimental and modeling studies have demonstrated how predicted ocean acidification and increased ultraviolet radiation (UVR) can affect marine microbes. However, researchers have largely ignored interactions between ocean acidification, increased UVR and anthropogenic pollutants in marine environments. Such interactions can alter chemical speciation and the bioavailability of several organic and inorganic pollutants with potentially deleterious effects, such as modifying microbial-mediated detoxification processes. Microbes mediate major biogeochemical cycles, providing fundamental ecosystems services such as environmental detoxification and recovery. It is, therefore, important that we understand how predicted changes to oceanic pH, UVR, and temperature will affect microbial pollutant detoxification processes in marine ecosystems. The intrinsic characteristics of microbes, such as their short generation time, small size, and functional role in biogeochemical cycles combined with recent advances in molecular techniques (e.g., metagenomics and metatranscriptomics) make microbes excellent models to evaluate the consequences of various climate change scenarios on detoxification processes in marine ecosystems. In this review, we highlight the importance of microbial microcosm experiments, coupled with high-resolution molecular biology techniques, to provide a critical experimental framework to start understanding how climate change, anthropogenic pollution, and microbiological interactions may affect marine ecosystems in the future. PMID:23789087

  18. Interactive effects of global climate change and pollution on marine microbes: the way ahead.

    PubMed

    Coelho, Francisco J R C; Santos, Ana L; Coimbra, Joana; Almeida, Adelaide; Cunha, Angela; Cleary, Daniel F R; Calado, Ricardo; Gomes, Newton C M

    2013-06-01

    Global climate change has the potential to seriously and adversely affect marine ecosystem functioning. Numerous experimental and modeling studies have demonstrated how predicted ocean acidification and increased ultraviolet radiation (UVR) can affect marine microbes. However, researchers have largely ignored interactions between ocean acidification, increased UVR and anthropogenic pollutants in marine environments. Such interactions can alter chemical speciation and the bioavailability of several organic and inorganic pollutants with potentially deleterious effects, such as modifying microbial-mediated detoxification processes. Microbes mediate major biogeochemical cycles, providing fundamental ecosystems services such as environmental detoxification and recovery. It is, therefore, important that we understand how predicted changes to oceanic pH, UVR, and temperature will affect microbial pollutant detoxification processes in marine ecosystems. The intrinsic characteristics of microbes, such as their short generation time, small size, and functional role in biogeochemical cycles combined with recent advances in molecular techniques (e.g., metagenomics and metatranscriptomics) make microbes excellent models to evaluate the consequences of various climate change scenarios on detoxification processes in marine ecosystems. In this review, we highlight the importance of microbial microcosm experiments, coupled with high-resolution molecular biology techniques, to provide a critical experimental framework to start understanding how climate change, anthropogenic pollution, and microbiological interactions may affect marine ecosystems in the future.

  19. 21. AERIAL VIEW OF THE ROCKY FLATS PLANT LOOKING NORTHWEST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    21. AERIAL VIEW OF THE ROCKY FLATS PLANT LOOKING NORTHWEST. BY THE LATE 1960S, THE SITE HAD UNDERGONE TWO MAJOR EXPANSIONS. THE FIRST EXPANSION IN 1956-57, WHEN THE TRIGGER DESIGN CHANGED AND NECESSITATED THE ADDITION OF SEVEN NEW BUILDINGS. THE SECOND LARGE EXPANSION TOOK PLACE FROM 1964-65, WHEN ROCKY FLATS BECAME THE SOLE PRODUCER OF TRIGGERS. DURING THIS EXPANSION, ELEVEN BUILDINGS WERE ADDED, PRIMARILY IN RESEARCH AND DEVELOPMENT LABORATORIES, GUARD HOUSES, AND WASTE WATER TREATMENT (7/1/69). - Rocky Flats Plant, Bounded by Indiana Street & Routes 93, 128 & 72, Golden, Jefferson County, CO

  20. On the potential for climate change impacts on marine anthropogenic radioactivity in the Arctic regions.

    PubMed

    Karcher, Michael; Harms, Ingo; Standring, William J F; Dowdall, Mark; Strand, Per

    2010-08-01

    Current predictions as to the impacts of climate change in general and Arctic climate change in particular are such that a wide range of processes relevant to Arctic contaminants are potentially vulnerable. Of these, radioactive contaminants and the processes that govern their transport and fate may be particularly susceptible to the effects of a changing Arctic climate. This paper explores the potential changes in the physical system of the Arctic climate system as they are deducible from present day knowledge and model projections. As a contribution to a better preparedness regarding Arctic marine contamination with radioactivity we present and discuss how a changing marine physical environment may play a role in altering the current understanding pertaining to behavior of contaminant radionuclides in the marine environment of the Arctic region.

  1. [Rocky Mountain spotted fever].

    PubMed

    Reinauer, K M; Jaschonek, K; Kusch, G; Heizmann, W R; Döller, P C; Jenss, H

    1990-01-12

    After returning from a holiday in the USA a 24-year-old man fell ill with diarrhoea, high fever and marked rash including the palms of the hands and soles of the feet. When a history of a tick bite in the USA was elicited, a rickettsial infection was suspected. Treatment with doxycycline, 100 mg twice daily, was instituted finally and the fever slowly resolved. The patient became completely well again within four weeks. Serological tests confirmed the diagnosis of Rocky Mountain spotted fever.

  2. Differences in Intertidal Microbial Assemblages on Urban Structures and Natural Rocky Reef

    PubMed Central

    Tan, Elisa L.-Y.; Mayer-Pinto, Mariana; Johnston, Emma L.; Dafforn, Katherine A.

    2015-01-01

    Global seascapes are increasingly modified to support high levels of human activity in the coastal zone. Modifications include the addition of defense structures and boating infrastructure, such as seawalls and marinas that replace natural habitats. Artificial structures support different macrofaunal communities to those found on natural rocky shores; however, little is known about differences in microbial community structure or function in urban seascapes. Understanding how artificial constructions in marine environments influence microbial communities is important as these assemblages contribute to many basic ecological processes. In this study, the bacterial communities of intertidal biofilms were compared between artificial structures (seawalls) and natural habitats (rocky shores) within Sydney Harbour. Plots were cleared on each type of habitat at eight locations. After 3 weeks the newly formed biofilm was sampled and the 16S rRNA gene sequenced using the Illumina Miseq platform. To account for differences in orientation and substrate material between seawalls and rocky shores that might have influenced our survey, we also deployed recruitment blocks next to the habitats at all locations for 3 weeks and then sampled and sequenced their microbial communities. Intertidal bacterial community structure sampled from plots differed between seawalls and rocky shores, but when substrate material, age and orientation were kept constant (with recruitment blocks) then bacterial communities were similar in composition and structure among habitats. This suggests that changes in bacterial communities on seawalls are not related to environmental differences between locations, but may be related to other intrinsic factors that differ between the habitats such as orientation, complexity, or predation. This is one of the first comparisons of intertidal microbial communities on natural and artificial surfaces and illustrates substantial ecological differences with potential

  3. Climate change-contaminant interactions in marine food webs: Toward a conceptual framework.

    PubMed

    Alava, Juan José; Cheung, William W L; Ross, Peter S; Sumaila, U Rashid

    2017-02-17

    Climate change is reshaping the way in which contaminants move through the global environment, in large part by changing the chemistry of the oceans and affecting the physiology, health, and feeding ecology of marine biota. Climate change-associated impacts on structure and function of marine food webs, with consequent changes in contaminant transport, fate, and effects, are likely to have significant repercussions to those human populations that rely on fisheries resources for food, recreation, or culture. Published studies on climate change-contaminant interactions with a focus on food web bioaccumulation were systematically reviewed to explore how climate change and ocean acidification may impact contaminant levels in marine food webs. We propose here a conceptual framework to illustrate the impacts of climate change on contaminant accumulation in marine food webs, as well as the downstream consequences for ecosystem goods and services. The potential impacts on social and economic security for coastal communities that depend on fisheries for food are discussed. Climate change-contaminant interactions may alter the bioaccumulation of two priority contaminant classes: the fat-soluble persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), as well as the protein-binding methylmercury (MeHg). These interactions include phenomena deemed to be either climate change dominant (i.e., climate change leads to an increase in contaminant exposure) or contaminant dominant (i.e., contamination leads to an increase in climate change susceptibility). We illustrate the pathways of climate change-contaminant interactions using case studies in the Northeastern Pacific Ocean. The important role of ecological and food web modeling to inform decision-making in managing ecological and human health risks of chemical pollutants contamination under climate change is also highlighted. Finally, we identify the need to develop integrated policies that manage the

  4. Organizational change and marine environmental protection: The dredge spoil siting record

    NASA Astrophysics Data System (ADS)

    Burroughs, R. H.

    1991-07-01

    Dredge spoil siting activities are reviewed over a decade to determine whether organizational changes within the Corps of Engineers produced changes in the environmental performance of the agency. Over the period neither the total amount of marine and estuarine dredging nor the incidence of siting spoil inside the baseline declined. Therefore, internal organizational changes do not appear to have affected the above measures of agency performance concerning protection of the marine environment. Furthermore, at least 3% of the spoil is estimated to be highly contaminated. In recent years this magnitude of contaminated spoils has been equivalent to ocean-dumped sewage sludge.

  5. Anthropogenic Climate Change in Undergraduate Marine and Environmental Science Programs in the United States

    ERIC Educational Resources Information Center

    Vlietstra, Lucy S.; Mrakovcich, Karina L.; Futch, Victoria C.; Stutzman, Brooke S.

    2016-01-01

    To develop a context for program-level design decisions pertaining to anthropogenic climate change, the authors studied the prevalence of courses focused on human-induced climate change in undergraduate marine science and environmental science degree programs in the United States. Of the 86 institutions and 125 programs the authors examined, 37%…

  6. 77 FR 65815 - Expansion of Fagatele Bay National Marine Sanctuary, Regulatory Changes, and Sanctuary Name...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-31

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 15 CFR Part 922 RIN 0648-BA24 Expansion of Fagatele Bay National Marine Sanctuary, Regulatory Changes, and Sanctuary Name Change; Notice of Effective Date...

  7. 77 FR 3646 - Proposed Expansion of Fagatele Bay National Marine Sanctuary, Regulatory Changes, and Sanctuary...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-25

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF COMMERCE National Oceanic and Atmospheric Administration 15 CFR Part 922 RIN 0648-BA24 Proposed Expansion of Fagatele Bay National Marine Sanctuary, Regulatory Changes, and Sanctuary Name Change AGENCY: Office...

  8. Habitat selection by marine larvae in changing chemical environments.

    PubMed

    Lecchini, D; Dixson, D L; Lecellier, G; Roux, N; Frédérich, B; Besson, M; Tanaka, Y; Banaigs, B; Nakamura, Y

    2017-01-15

    The replenishment and persistence of marine species is contingent on dispersing larvae locating suitable habitat and surviving to a reproductive stage. Pelagic larvae rely on environmental cues to make behavioural decisions with chemical information being important for habitat selection at settlement. We explored the sensory world of crustaceans and fishes focusing on the impact anthropogenic alterations (ocean acidification, red soil, pesticide) have on conspecific chemical signals used by larvae for habitat selection. Crustacean (Stenopus hispidus) and fish (Chromis viridis) larvae recognized their conspecifics via chemical signals under control conditions. In the presence of acidified water, red soil or pesticide, the ability of larvae to chemically recognize conspecific cues was altered. Our study highlights that recruitment potential on coral reefs may decrease due to anthropogenic stressors. If so, populations of fishes and crustaceans will continue their rapid decline; larval recruitment will not replace and sustain the adult populations on degraded reefs.

  9. Changing environments and structure–property relationships in marine biomaterials

    PubMed Central

    Waite, J. Herbert; Broomell, Christopher C.

    2012-01-01

    Summary Most marine organisms make functional biomolecular materials that extend to varying degrees ‘beyond their skins’. These materials are very diverse and include shells, spines, frustules, tubes, mucus trails, egg capsules and byssal threads, to mention a few. Because they are devoid of cells, these materials lack the dynamic maintenance afforded intra-organismic tissues and thus are usually assumed to be inherently more durable than their internalized counterparts. Recent advances in nanomechanics and submicron spectroscopic imaging have enabled the characterization of structure–property relationships in a variety of extra-organismic materials and provided important new insights about their adaptive functions and stability. Some structure–property relationships in byssal threads are described to show how available analytical methods can reveal hitherto unappreciated interdependences between these materials and their prevailing chemical, physical and ecological environments. PMID:22357581

  10. Integrating Climate Change Resilience Features into the Incremental Refinement of an Existing Marine Park

    PubMed Central

    Beckley, Lynnath E.; Kobryn, Halina T.; Lombard, Amanda T.; Radford, Ben; Heyward, Andrew

    2016-01-01

    Marine protected area (MPA) designs are likely to require iterative refinement as new knowledge is gained. In particular, there is an increasing need to consider the effects of climate change, especially the ability of ecosystems to resist and/or recover from climate-related disturbances, within the MPA planning process. However, there has been limited research addressing the incorporation of climate change resilience into MPA design. This study used Marxan conservation planning software with fine-scale shallow water (<20 m) bathymetry and habitat maps, models of major benthic communities for deeper water, and comprehensive human use information from Ningaloo Marine Park in Western Australia to identify climate change resilience features to integrate into the incremental refinement of the marine park. The study assessed the representation of benthic habitats within the current marine park zones, identified priority areas of high resilience for inclusion within no-take zones and examined if any iterative refinements to the current no-take zones are necessary. Of the 65 habitat classes, 16 did not meet representation targets within the current no-take zones, most of which were in deeper offshore waters. These deeper areas also demonstrated the highest resilience values and, as such, Marxan outputs suggested minor increases to the current no-take zones in the deeper offshore areas. This work demonstrates that inclusion of fine-scale climate change resilience features within the design process for MPAs is feasible, and can be applied to future marine spatial planning practices globally. PMID:27529820

  11. 26. AERIAL VIEW OF THE ROCKY FLATS PLANT LOOKING NORTHEAST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. AERIAL VIEW OF THE ROCKY FLATS PLANT LOOKING NORTHEAST. IN 1951, A GOOD FRIDAY ISSUE OF THE DENVER POST ANNOUNCED THE ATOMIC ENERGY COMMISSION'S PLANS TO BUILD THE ROCKY FLATS PLANT. UNDER THE HEADLINE 'THERE'S GOOD NEWS TODAY.' POLITICAL LEADERS EXPRESSED GREAT PRIDE IN THE CHOICE OF THE DENVER-BOULDER AREA AS THE SITE FOR AN ATOMIC PLANT AS QUOTED IN THE ROCKY MOUNTAIN NEWS: 'WE ARE PROUD THAT THE AREA HAS BEEN CHOSEN FOR ANOTHER IMPORTANT CONTRIBUTION TO THE NATION'S STRENGTH AND FUTURE SECURITY.' BY THE MID 1970S, PUBLIC OPINION OF THE SITE HAD CHANGED (5/4/78). - Rocky Flats Plant, Bounded by Indiana Street & Routes 93, 128 & 72, Golden, Jefferson County, CO

  12. Rocky Mountain spotted fever.

    PubMed

    Dantas-Torres, Filipe

    2007-11-01

    Rocky Mountain spotted fever (RMSF) is a life-threatening disease caused by Rickettsia rickettsii, an obligately intracellular bacterium that is spread to human beings by ticks. More than a century after its first clinical description, this disease is still among the most virulent human infections identified, being potentially fatal even in previously healthy young people. The diagnosis of RMSF is based on the patient's history and a physical examination, and often presents a dilemma for clinicians because of the non-specific presentation of the disease in its early course. Early empirical treatment is essential to prevent severe complications or a fatal outcome, and treatment should be initiated even in unconfirmed cases. Because there is no vaccine available against RMSF, avoidance of tick-infested areas is still the best way to prevent the infection.

  13. Future vulnerability of marine biodiversity compared with contemporary and past changes

    NASA Astrophysics Data System (ADS)

    Beaugrand, Grégory; Edwards, Martin; Raybaud, Virginie; Goberville, Eric; Kirby, Richard R.

    2015-07-01

    Many studies have implied significant effects of global climate change on marine life. Setting these alterations into the context of historical natural change has not been attempted so far, however. Here, using a theoretical framework, we estimate the sensitivity of marine pelagic biodiversity to temperature change and evaluate its past (mid-Pliocene and Last Glacial Maximum (LGM)), contemporaneous (1960-2013) and future (2081-2100 4 scenarios of warming) vulnerability. Our biodiversity reconstructions were highly correlated to real data for several pelagic taxa for the contemporary and the past (LGM and mid-Pliocene) periods. Our results indicate that local species loss will be a prominent phenomenon of climate warming in permanently stratified regions, and that local species invasion will prevail in temperate and polar biomes under all climate change scenarios. Although a small amount of warming under the RCP2.6 scenario is expected to have a minor influence on marine pelagic biodiversity, moderate warming (RCP4.5) will increase by threefold the changes already observed over the past 50 years. Of most concern is that severe warming (RCP6.0 and 8.5) will affect marine pelagic biodiversity to a greater extent than temperature changes that took place between either the LGM or the mid-Pliocene and today, over an area of between 50 (RCP6.0: 46.9-52.4%) and 70% (RCP8.5: 69.4-73.4%) of the global ocean.

  14. A Record of Environmental Change in Caribbean Coral Reefs: Sclerochronology and Geochemistry of O. faveolata as a Paleoclimate Proxy at Coral Gardens and Rocky Point, Belize

    NASA Astrophysics Data System (ADS)

    DeCorte, I. A.; Greer, L.; Wirth, K. R.; Flowers Falls, E.; Lescinsky, H.; Doss, W. C.

    2015-12-01

    Over the last several decades, Acropora cervicornis has seen a massive die-off in the Caribbean. (Aronson and Precht 2001; Gardner et al., 2003; Greer et al., 2009). The potential causes of decline in A. cervicornis in the Caribbean include: extremes in sea surface temperatures (SST), ocean acidification, eutrophication, white-band disease, storm disturbances, and other anthropogenic disturbances. Contrary to the regional decline in A. cervicornis, Coral Gardens on the Belize Barrier Reef has an Acropora sp. population that appears to be thriving. Through a combination of sclerochronology, stable isotope analysis, and in situ sensor data, this work capitilizes on the opportunity to study reef conditions in a site where micro-environmental conditions appear to be favorable for healthy A. cervicornis coral growth. We use cores from two Orbicella faveolata colonies located within Acropora stands, as A. cervicornis does not reveal annual banding. We compare two cores from one O. faveolata colony at Coral Gardens, first cored in 2011 and again in 2014, to one O. faveolata core at near-by Rocky Point, where A. cervicornis is much less abundant. These cores were x-radiographed in order to expose the annual banding and sampled for stable oxygen and carbon isotope analysis (10-15 samples/cm). We show that, although there are no significant differences in the range of the δ18O and δ13C signature between Rocky Point and Coral Gardens, there is a clear difference in the stress histories at these locations as inferred from linear extension rates (LER's) and annual banding patterns. Rocky Point averages a LER of 10.5±1.4 mm/year (n = 29) over a 30 year record and Coral Gardens averages 9.1±1.2 mm/year (n = 70) from ~1953 - 2001, and averages 6.2±1.6 mm/year (n = 36) from coral years 2001-2014 after an inferred stress-banding event. This is in contrast to the observed overall health of A. cervicornis at the two locations. The inferred stress-banding event is currently

  15. Changes in the marine pollution management system in response to the Amorgos oil spill in Taiwan.

    PubMed

    Chiau, Wen-Yen

    2005-01-01

    The Marine Pollution Control Act (MPCA) of Taiwan was promulgated on November 1, 2000, with the specific aim of controlling marine pollution, safeguarding public health, and promoting the sustainable use of marine resources. In addition to land-based pollution, oil spills are one of the most significant threats to the local marine environment largely on account of the some 30,000 tankers which pass through Taiwan's coastal waters each year. In January 2001, two months after the enactment of this newly-introduced law, a Greek merchant vessel, the Amorgos ran aground in the vicinity of a national park on the southern tip of Taiwan, causing a serious oil spill and leading to considerable changes with regard to the marine pollution management system. The incident brought to the forefront many serious problems, such as a lack of experience, expertise as well as equipment required to respond to such disasters, as well as the ambiguous, unclear jurisdiction among related agencies. Thus, this paper reviews the incident of the Amorgos spill, identifies the major issues and lessons learned, and proposes several recommendations in an effort for Taiwan to further improve its marine pollution management system.

  16. Spatial and temporal patterns of stranded intertidal marine debris: is there a picture of global change?

    PubMed

    Browne, Mark Anthony; Chapman, M Gee; Thompson, Richard C; Amaral Zettler, Linda A; Jambeck, Jenna; Mallos, Nicholas J

    2015-06-16

    Floating and stranded marine debris is widespread. Increasing sea levels and altered rainfall, solar radiation, wind speed, waves, and oceanic currents associated with climatic change are likely to transfer more debris from coastal cities into marine and coastal habitats. Marine debris causes economic and ecological impacts, but understanding the scope of these requires quantitative information on spatial patterns and trends in the amounts and types of debris at a global scale. There are very few large-scale programs to measure debris, but many peer-reviewed and published scientific studies of marine debris describe local patterns. Unfortunately, methods of defining debris, sampling, and interpreting patterns in space or time vary considerably among studies, yet if data could be synthesized across studies, a global picture of the problem may be avaliable. We analyzed 104 published scientific papers on marine debris in order to determine how to evaluate this. Although many studies were well designed to answer specific questions, definitions of what constitutes marine debris, the methods used to measure, and the scale of the scope of the studies means that no general picture can emerge from this wealth of data. These problems are detailed to guide future studies and guidelines provided to enable the collection of more comparable data to better manage this growing problem.

  17. Marine phytoplankton and the changing ocean iron cycle

    NASA Astrophysics Data System (ADS)

    Hutchins, D. A.; Boyd, P. W.

    2016-12-01

    The availability of the micronutrient iron governs phytoplankton growth across much of the ocean, but the global iron cycle is changing rapidly due to accelerating acidification, stratification, warming and deoxygenation. These mechanisms of global change will cumulatively affect the aqueous chemistry, sources and sinks, recycling, particle dynamics and bioavailability of iron. Biological iron demand will vary as acclimation to environmental change modifies cellular requirements for photosynthesis and nitrogen acquisition and as adaptive evolution or community shifts occur. Warming, acidification and nutrient co-limitation interactions with iron biogeochemistry will all strongly influence phytoplankton dynamics. Predicting the shape of the future iron cycle will require understanding the responses of each component of the unique biogeochemistry of this trace element to many concurrent and interacting environmental changes.

  18. Evolutionary adaptation of marine zooplankton to global change.

    PubMed

    Dam, Hans G

    2013-01-01

    Predicting the response of the biota to global change remains a formidable endeavor. Zooplankton face challenges related to global warming, ocean acidification, the proliferation of toxic algal blooms, and increasing pollution, eutrophication, and hypoxia. They can respond to these changes by phenotypic plasticity or genetic adaptation. Using the concept of the evolution of reaction norms, I address how adaptive responses can be unequivocally discerned from phenotypic plasticity. To date, relatively few zooplankton studies have been designed for such a purpose. As case studies, I review the evidence for zooplankton adaptation to toxic algal blooms, hypoxia, and climate change. Predicting the response of zooplankton to global change requires new information to determine (a) the trade-offs and costs of adaptation, (b) the rates of evolution versus environmental change, (c) the consequences of adaptation to stochastic or cyclic (toxic algal blooms, coastal hypoxia) versus directional (temperature, acidification, open ocean hypoxia) environmental change, and (d) the interaction of selective pressures, and evolutionary and ecological processes, in promoting or hindering adaptation.

  19. Marine mammal strandings and environmental changes: a 15-year study in the St. Lawrence ecosystem.

    PubMed

    Truchon, Marie-Hélène; Measures, Lena; L'Hérault, Vincent; Brêthes, Jean-Claude; Galbraith, Peter S; Harvey, Michel; Lessard, Sylvie; Starr, Michel; Lecomte, Nicolas

    2013-01-01

    Understanding the effects of climatic variability on marine mammals is challenging due to the complexity of ecological interactions. We used general linear models to analyze a 15-year database documenting marine mammal strandings (1994-2008; n = 1,193) and nine environmental parameters known to affect marine mammal survival, from regional (sea ice) to continental scales (North Atlantic Oscillation, NAO). Stranding events were more frequent during summer and fall than other seasons, and have increased since 1994. Poor ice conditions observed during the same period may have affected marine mammals either directly, by modulating the availability of habitat for feeding and breeding activities, or indirectly, through changes in water conditions and marine productivity (krill abundance). For most species (75%, n = 6 species), a low volume of ice was correlated with increasing frequency of stranding events (e.g. R(2)adj = 0.59, hooded seal, Cystophora cristata). This likely led to an increase in seal mortality during the breeding period, but also to increase habitat availability for seasonal migratory cetaceans using ice-free areas during winter. We also detected a high frequency of stranding events for mysticete species (minke whale, Balaenoptera acutorostrata) and resident species (beluga, Delphinapterus leucas), correlated with low krill abundance since 1994. Positive NAO indices were positively correlated with high frequencies of stranding events for resident and seasonal migratory cetaceans, as well as rare species (R(2)adj = 0.53, 0.81 and 0.34, respectively). This contrasts with seal mass stranding numbers, which were negatively correlated with a positive NAO index. In addition, an unusual multiple species mortality event (n = 114, 62% of total annual mortality) in 2008 was caused by a harmful algal bloom. Our findings provide an empirical baseline in understanding marine mammal survival when faced with climatic variability. This is a promising

  20. Climate change impacts on marine water quality: The case study of the Northern Adriatic sea.

    PubMed

    Rizzi, J; Torresan, S; Critto, A; Zabeo, A; Brigolin, D; Carniel, S; Pastres, R; Marcomini, A

    2016-01-30

    Climate change is posing additional pressures on coastal ecosystems due to variations in water biogeochemical and physico-chemical parameters (e.g., pH, salinity) leading to aquatic ecosystem degradation. With the main aim of analyzing the potential impacts of climate change on marine water quality, a Regional Risk Assessment methodology was developed and applied to coastal marine waters of the North Adriatic. It integrates the outputs of regional biogeochemical and physico-chemical models considering future climate change scenarios (i.e., years 2070 and 2100) with site-specific environmental and socio-economic indicators. Results showed that salinity and temperature will be the main drivers of changes, together with macronutrients, especially in the area of the Po' river delta. The final outputs are exposure, susceptibility and risk maps supporting the communication of the potential consequences of climate change on water quality to decision makers and stakeholders and provide a basis for the definition of adaptation and management strategies.

  1. Sensitivities of marine carbon fluxes to ocean change

    PubMed Central

    Riebesell, Ulf; Körtzinger, Arne; Oschlies, Andreas

    2009-01-01

    Throughout Earth's history, the oceans have played a dominant role in the climate system through the storage and transport of heat and the exchange of water and climate-relevant gases with the atmosphere. The ocean's heat capacity is ≈1,000 times larger than that of the atmosphere, its content of reactive carbon more than 60 times larger. Through a variety of physical, chemical, and biological processes, the ocean acts as a driver of climate variability on time scales ranging from seasonal to interannual to decadal to glacial–interglacial. The same processes will also be involved in future responses of the ocean to global change. Here we assess the responses of the seawater carbonate system and of the ocean's physical and biological carbon pumps to (i) ocean warming and the associated changes in vertical mixing and overturning circulation, and (ii) ocean acidification and carbonation. Our analysis underscores that many of these responses have the potential for significant feedback to the climate system. Because several of the underlying processes are interlinked and nonlinear, the sign and magnitude of the ocean's carbon cycle feedback to climate change is yet unknown. Understanding these processes and their sensitivities to global change will be crucial to our ability to project future climate change. PMID:19995981

  2. Rocky Mountain Arsenal NPDES Permit

    EPA Pesticide Factsheets

    Under NPDES permit CO-0035009, the U.S. Department of Interior's Fish and Wildlife Service is authorized to discharge from the Rocky Mountain Arsenal recycled water pipeline to Lower Derby Lake in Adams County, Colo.

  3. Regional-scale analysis of subtidal rocky shore community

    NASA Astrophysics Data System (ADS)

    Derrien-Courtel, Sandrine; Le Gal, Aodren; Grall, Jacques

    2013-12-01

    The French monitoring network, REseau BENThique (REBENT), was launched by the Ministry of the Environment in 2003 following the 1999 Erika oil spill. REBENT aimed to acquire baseline knowledge of coastal benthic habitat distributions with a special focus on biological diversity. This study analyzed data from 38 subtidal rocky reef sites collected by a single diving team of marine biologists along the coast of Brittany from 2004 to 2010. At each site, the depth limits of the algal belts were determined between 0 and -40 m Chart Datum (CD); the flora and fauna compositions and abundances were sampled at -3 and -8 m CD. A total of 364 taxa (156 flora and 208 fauna), belonging to 12 phyla, were identified. The results showed that the depth limit and density of kelp beds increased as water turbidity decreased; moreover, several changes in community structure could be related to water turbidity and temperature. Thus, northern and southern Brittany showed strong differences in diversity and structure of the dominant kelp species ( Laminaria hyperborea and Saccorhiza polyschides). The results from this kelp habitat composition survey (dominant kelp species and indicator species) provided important information for local pressure assessments, like increases in turbidity. The data also provided a reference that could be useful for detecting changes in coastal water temperatures due to global warming.

  4. Climate change and marine fish distributions: Forecasting from historical analogy

    SciTech Connect

    Murawski, S.A. )

    1993-09-01

    Analyses of 36 fish and squid species sampled in standardized bottom-trawl surveys of the northwest Atlantic Ocean (1967-present) revealed a continuum of distributional responses associated with seasonal and annual variations in water temperature. Mean and maximum latitude of occurrence of the species were regressed against average surface- and bottom-water temperatures and indices of relative abundance from spring and autumn trawl surveys. Significant (P [le] 0.05) regression models were fitted for 17 of 36 species from spring and fall survey data. Variations in water temperature were significant in explaining changes in mean latitude of occurrence for 12 of 36 species in both seasons. Maximum latitude distribution responses to interannual differences in water temperatures occurred for pelagic species, including Atlantic mackerel Scomber scombrus and Atlantic herring Clupea harengus. Weighted mean catches of these species shifted poleward by 0.5-0.8 degree of latitude for each 1[degrees]C increase in average water temperature. Statistically significant poleward range extensions, associated with warmer water temperatures, occurred for five species in spring surveys and four in fall surveys. Different responses among species to changing thermal regimes of the northwest Atlantic Shelf have important potential consequences for trophic dynamics and fisheries yields of the ecosystem. Species found to be sensitive in distribution to temperature change include primary prey species of some predators that show limited seasonal or annual changes in distribution. Changes in distributional overlaps between some predators and prey therefore are a likely result of shelf warming associated with climate change. 20 refs., 5 figs., 4 tabs.

  5. Rocky Martian Plain

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The rocky Martian plain surrounding Viking 2 is seen in high resolution in this 85-degree panorama sweeping from north at the left to east at right during the Martian afternoon on September 5. Large blocks litter the surface. Some are porous, sponge-like rocks like the one at the left edge (size estimate: 1 1/2 to 2 feet); others are dense and fine-grained, such as the very bright rounded block (1 to 1 1/2 feet across) toward lower right. Pebbled surface between the rocks is covered in places by small drifts of very fine material similar to drifts seen at the Viking 1 landing site some 4600 miles to the southwest. The fine-grained material is banked up behind some rocks, but wind tails seen by Viking 1 are not well-developed here. On the right horizon, flat-topped ridges or hills are illuminated by the afternoon sun. Slope of the horizon is due to the 8-degree tilt of the spacecraft.

  6. Drought in the Rockies

    NASA Technical Reports Server (NTRS)

    2002-01-01

    This image shows the difference between the amount of vegetation in July 2000 and the average July vegetation for North America. Of particular interest are the dry conditions in the western United States. This spring and summer the Rocky Mountains have been relatively dry, and the brown regions stretching from the Canadian to the Mexican border, indicate the effect on the regions' forests. Western Montana and eastern Idaho are particularly parched, and appear darker brown. The dry conditions have contributed to this year's devastating fire season, during which millions of acres have burned in the west. Scientists find that during the growing season, land plants can be used to measure drought. Healthy, thriving plants reflect and absorb visible and near-infrared light differently than plants under stress. These variations in reflectance and absorption can be measured by satellites to produce maps of healthy and stressed vegetation. This image shows Normalized Difference Vegetation Index (NDVI) anomaly, which indicates where vegetation growth was above average (green pixels), below average (brown pixels), or normal (white pixels). For more images and information about measuring vegetation and drought from space visit: Drought and Vegetation Monitoring. Image courtesy NASA Goddard Space Flight Center Biospheric Sciences Branch, based on data from NOAA.

  7. Regional scale estimation of carbon fluxes from long-term monitoring of intertidal exposed rocky shore communities

    NASA Astrophysics Data System (ADS)

    Tagliarolo, Morgana; Grall, Jacques; Chauvaud, Laurent; Clavier, Jacques

    2015-09-01

    The observed increase in the atmospheric concentration of carbon dioxide due to anthropogenic emissions is predicted to lead to significant changes in climate. Recent studies highlight the importance of identifying the role of marine coastal communities in carbon exchanges. Our objective was to couple macrozoobenthos abundance data from long-term monitoring with species metabolism rates to contribute to the estimation of CO2 fluxes from an intertidal exposed rocky shore community at a regional scale. The carbon fluxes due to respiration and calcification were calculated both during emersion and immersion, and the effect of temperature variation on carbon emissions was then predicted. Spatial and temporal natural variations of carbon fluxes were investigated and the contribution of exposed intertidal rocky shore communities to regional carbon emissions was calculated. The method was used to calculate the carbon budget allowed to account for the natural spatial variability of the community composition and carbon emissions. Mean annual calculated CO2 emission was 14.3 mol C m- 2 yr- 2, and the annual regional CO2 flux was estimated at 2978 t C yr- 1. Simulations showed that the potential feedback of a rise in temperature of 1 °C would lead to an increase of 4-7% in carbon emissions for this type of community. The results give a first quantification of intertidal exposed rocky shore carbon emissions that could be considered in evaluating further the global CO2 budget.

  8. Temporal changes in artificial light exposure of marine turtle nesting areas.

    PubMed

    Kamrowski, Ruth L; Limpus, Col; Jones, Rhondda; Anderson, Sharolyn; Hamann, Mark

    2014-08-01

    Artificial light at night poses a significant threat to multiple taxa across the globe. In coastal regions, artificial lighting close to marine turtle nesting beaches is disruptive to their breeding success. Prioritizing effective management of light pollution requires an understanding of how the light exposure of nesting areas changes over time in response to changing temporal and spatial distributions of coastal development. We analyzed multitemporal, satellite night-light data, in combination with linear mixed model analysis, to determine broadscale changes in artificial light exposure at Australian marine turtle nesting areas between 1993 and 2010. We found seven marine turtle management units (MU), from five species, have experienced significant increases in light exposure over time, with flatback turtles nesting in east Australia experiencing the fastest increases. The remaining 12 MUs showed no significant change in light exposure. Unchanging MUs included those previously identified as having high exposure to light pollution (located in western Australia and southern Queensland), indicating that turtles in these areas have been potentially exposed to high light levels since at least the early nineties. At a finer geographic scale (within-MU), nine MUs contained nesting areas with significant increases in light exposure. These nesting areas predominantly occurred close to heavily industrialized coastal areas, thus emphasizing the importance of rigorous light management in industry. Within all MUs, nesting areas existed where light levels were extremely low and/or had not significantly increased since 1993. With continued coastal development, nesting females may shift to these darker/unchanging 'buffer' areas in the future. This is valuable information that informs our understanding of the capacity and resilience of marine turtles faced with coastal development: an understanding that is essential for effective marine turtle conservation.

  9. Rocky Flats beryllium health surveillance

    SciTech Connect

    Stange, A.W.; Furman, F.J.; Hilmas, D.E.

    1996-10-01

    The Rocky Flats Beryllium Health Surveillance Program (BHSP), initiated in June 1991, was designed to provide medical surveillance for current and former employees exposed to beryllium. The BHSP identifies individuals who have developed beryllium sensitivity using the beryllium lymphocyte proliferation test (BeLPT). A detailed medical evaluation to determine the prevalence of chronic beryllium disease (CBD) is offered to individuals identified as beryllium sensitized or to those who have chest X-ray changes suggestive of CBD. The BHSP has identified 27 cases of CBD and another 74 cases of beryllium sensitization out of 4268 individuals tested. The distribution of BeLPT values for normal, sensitized, and CBD-identified individuals is described. Based on the information collected during the first 3 1/3 years of the BHSP, the BeLPT is the most effective means for the early identification of beryllium-sensitized individuals and to identify individuals who may have CBD. The need for BeLPT retesting is demonstrated through the identification of beryllium sensitization in individuals who previously tested normal. Posterior/anterior chest X-rays were not effective in the identification of CBD. 12 refs., 8 tabs.

  10. Detection of environmental change in a marine ecosystem--evidence from the western English Channel.

    PubMed

    Hawkins, Stephen J; Southward, Alan J; Genner, Martin J

    2003-07-01

    To separate human-induced changes from natural fluctuations in marine life requires long-term research. The western English Channel has been investigated from Plymouth for over 100 years. The abundance of marine life has been recorded and related to physical changes in the environment. By comparing different parts of the ecosystem we can demonstrate historic natural fluctuations, allowing prediction of effects of future global change. From the 1920s to the 1950s there was a period of warming of the sea, with increases in abundance of species of fish, plankton and intertidal organisms that are typically common in warmer waters to the south of Britain. After 1962 the sea cooled down and northern cold-water species became more abundant. Since the 1980s regional sea surface temperature has increased again and warm-water species are once more becoming abundant.

  11. Force majeure: Will climate change affect our ability to attain Good Environmental Status for marine biodiversity?

    PubMed

    Elliott, Michael; Borja, Ángel; McQuatters-Gollop, Abigail; Mazik, Krysia; Birchenough, Silvana; Andersen, Jesper H; Painting, Suzanne; Peck, Myron

    2015-06-15

    The EU Marine Strategy Framework Directive (MSFD) requires that Good Environmental Status (GEnS), is achieved for European seas by 2020. These may deviate from GEnS, its 11 Descriptors, targets and baselines, due to endogenic managed pressures (from activities within an area) and externally due to exogenic unmanaged pressures (e.g. climate change). Conceptual models detail the likely or perceived changes expected on marine biodiversity and GEnS Descriptors in the light of climate change. We emphasise that marine management has to accommodate 'shifting baselines' caused by climate change particularly during GEnS monitoring, assessment and management and 'unbounded boundaries' given the migration and dispersal of highly-mobile species. We suggest climate change may prevent GEnS being met, but Member States may rebut legal challenges by claiming that this is outside its control, force majeure or due to 'natural causes' (Article 14 of the MSFD). The analysis is relevant to management of other global seas.

  12. A century later: Long-term change of an inshore temperate marine fish assemblage

    NASA Astrophysics Data System (ADS)

    McHugh, Matthew; Sims, David W.; Partridge, Julian C.; Genner, Martin J.

    2011-02-01

    There is compelling evidence that European marine fish assemblages have undergone extensive changes in composition over the last century. However, our knowledge of which species have changed in abundance and body size distributions, and the reasons for these changes, is limited due to a paucity of historical data. Here we report a study of long-term change in a marine fish assemblage from the inshore waters of the Western English Channel, near Plymouth. We compiled data from historic trawls undertaken between 1913 and 1922, and resurveyed those sites in 2008 and 2009. Our results revealed highly significant temporal differences in assemblage composition, but the scale of change was not consistent among taxonomic groups. Dramatic changes were recorded within the elasmobranchs, characterised by a reduction in abundance of all skate (Rajiidae) species, apparent extirpation of the angel shark ( Squatina squatina), and large increases in the abundance of lesser-spotted catshark ( Scyliorhinus canicula). By contrast we observed less evidence of change among 'flatfishes' (Pleuronectiformes) or 'roundfishes' (other teleosts). Changes were also observed in length-frequency distributions, with a significant decline in the size distribution of elasmobranchs (excluding S. canicula), but no significant change in size distributions of either group of teleosts. These data provide further evidence that larger, slow-maturing species have undergone declines in UK waters over the last century, and form useful benchmarks for assessment of future changes in this coastal faunal assemblage.

  13. 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.

  14. Developing climate change indicators and a climate change monitoring plan for decision-makers at a National Marine Sanctuary

    NASA Astrophysics Data System (ADS)

    Duncan, B.; Higgason, K.; Suchanek, T.; Stachowicz, J.; Cayan, D. R.

    2012-12-01

    Changes in physical and biological components of the ecosystem along the North-central California coast have been identified as likely regional impacts of global climate change. To better monitor and address these impacts, physical and biological climate change indicators are identified for the region stretching from Bodega Head to Año Nuevo. This effort is based at the Gulf of the Farallones National Marine Sanctuary, and it is the first of its kind within the National Marine Sanctuary system. The set of climate change indicators is developed following a rigorous and collaborative process that incorporates an extensive literature review, a large workshop with regional research scientists and managers, statistical downscaling of available general circulation model and regional climate model output, and analysis of available indicator data. Work is underway to incorporate the final set of climate change indicators into a comprehensive climate change monitoring inventory and plan, with significant input from a working group of regional scientific experts. The collaborative nature of this project helps to ensure that the chosen indicators can and will be used by scientists, natural resource managers, and state and municipal planners to monitor, track, mitigate, and develop adaptation strategies for the impacts of climate change on the North-central California coast.

  15. Predicting ecological changes on benthic estuarine assemblages through decadal climate trends along Brazilian Marine Ecoregions

    NASA Astrophysics Data System (ADS)

    Bernardino, Angelo F.; Netto, Sérgio A.; Pagliosa, Paulo R.; Barros, Francisco; Christofoletti, Ronaldo A.; Rosa Filho, José S.; Colling, André; Lana, Paulo C.

    2015-12-01

    Estuaries are threatened coastal ecosystems that support relevant ecological functions worldwide. The predicted global climate changes demand actions to understand, anticipate and avoid further damage to estuarine habitats. In this study we reviewed data on polychaete assemblages, as a surrogate for overall benthic communities, from 51 estuaries along five Marine Ecoregions of Brazil (Amazonia, NE Brazil, E Brazil, SE Brazil and Rio Grande). We critically evaluated the adaptive capacity and ultimately the resilience to decadal changes in temperature and rainfall of the polychaete assemblages. As a support for theoretical predictions on changes linked to global warming we compared the variability of benthic assemblages across the ecoregions with a 40-year time series of temperature and rainfall data. We found a significant upward trend in temperature during the last four decades at all marine ecoregions of Brazil, while rainfall increase was restricted to the SE Brazil ecoregion. Benthic assemblages and climate trends varied significantly among and within ecoregions. The high variability in climate patterns in estuaries within the same ecoregion may lead to correspondingly high levels of noise on the expected responses of benthic fauna. Nonetheless, we expect changes in community structure and productivity of benthic species at marine ecoregions under increasing influence of higher temperatures, extreme events and pollution.

  16. Is climate change an unforeseen, irresistible and external factor - A force majeure in marine environmental law?

    PubMed

    Saul, Roxanne; Barnes, Richard; Elliott, Michael

    2016-12-15

    Several environmental laws include provisions on natural causes or force majeure, which except States from their commitments if it can be proven that the failure to meet the commitment is due to factors outside their control. The European Union Marine Strategy Framework Directive (MSFD) has a pivotal role in managing EU marine waters. This paper analyses natural causes and force majeure provisions of the MFSD and other marine legislation, and addresses their interaction with climate change and its consequences, especially the effect on the obligation of ensuring seas are in Good Environmental Status. Climate change is an exogenic unmanaged pressure in that it emanates from outside the area being managed but in which the management authority has to respond to the consequences of climate change, such as sea level rise and temperature elevation, rather than its causes. It is suggested that a defence by a Member State of force majeure may be accepted if an event was proven to be due to an externality of control, irresistible and unforeseeable. The analysis contends that countering such a legal defence would centre on the fact that climate change is a well-accepted phenomenon, is foreseen with an accepted level of confidence and probability and is due to human actions. However, as yet, this has not been legally tested.

  17. 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.

  18. 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.

  19. 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

  20. Monitoring marine ecological changes on the east coast of Bahrain with Landsat TM

    SciTech Connect

    Zainal, A.J.M.; Dalby, D.H.; Robinson, I.S. Michigan Environmental Research Inst., Ann Arbor )

    1993-03-01

    An evaluation is made of the potential of Landsat TM imagery for detecting and quantifying the changes occurring in the marine habitat of a reef complex on the east coast of Bahrain. The study gives attention to TM images acquired during 1985-1992 under various tidal conditions; principal component and false color composites of the temporal images were applied to these to identify changed areas. Then, postclassification comparisons were employed together with digital elevation data to quantify the magnitude of habitat change. 11 refs.

  1. Morphodynamics of a mesotidal rocky beach: Palmeras beach, Gorgona Island National Natural Park, Colombia

    NASA Astrophysics Data System (ADS)

    Gómez-García, A. M.; Bernal, G. R.; Osorio, A. F.; Botero, V.

    2014-10-01

    The response of a rocky beach to different possible combinations of hydrodynamic conditions (tides, waves, oceanic currents) has been little studied. In this work, the morphodynamic response to different hydrodynamic forcing is evaluated from sedimentological and geomorphological analysis in seasonal and medium term (19 years) scale in Palmeras beach, located in the southwest of Gorgona Island National Natural Park (NNP), a mesotidal rocky island on the Colombian Pacific continental shelf. Palmeras is an important nesting area of two types of marine turtles, with no anthropogenic stress. In the last years, coastal erosion has reduced the beach width, restricting the safe areas for nesting and conservation of these species. Until now, the sinks, sources, reservoirs, rates, and paths of sediments were unknown, as well as their hydrodynamic forcing. The beach seasonal variability, from October 2010 to August 2012, was analyzed based on biweekly or monthly measurements of five beach profiles distributed every 200 m along the 1.2 km of beach length. The main paths for sediment transport were defined from the modeling of wave currents with the SMC model (Coastal Modeling System), as well as the oceanic currents, simulated for the dry and wet seasons of 2011 using the ELCOM model (Estuary and Lake COmputer Model). Extreme morphologic variations over a time span of 19 years were analyzed with the Hsu and Evans beach static equilibrium parabolic model, from one wave diffraction point which dominates the general beach plan shape. The beach lost 672 m3/m during the measuring period, and erosional processes were intensified during the wet season. The beach trends responded directly to a wave mean energy flux change, resulting in an increase of up to 14 m in the width northward and loss of sediments in the beach southward. This study showed that to obtain the integral morphodynamic behavior of a rocky beach it is necessary to combine information of hydrodynamic, sedimentology

  2. Sea level change and glacio-hydro isostasy deduced from some Italian marine notches

    NASA Astrophysics Data System (ADS)

    Antonioli, F.; Carulli, G. B.; Marocco, R.

    2003-04-01

    Sea level change along the Italian coast is the sum of eustatic, glacio-hydro-isostatic, and tectonic factors (Lambeck et al.,submitted 2003). Marine notches are frequently found in limestones lithologies. A marine notch is normally carved in 2-5 centuries and this range depends upon the lithology. The use of notches as sea level marker in a low-tide seas as Mediterranean, is crucial to study the sea level change. In many Italian tectonically active coastal zone uplifting (eastern Sicily) o subsiding (Trieste, north Adriatic sea) the Present day marine notches are lacking because the tectonic ratea are faster than the possibility of carving. A submerged marine notch was discovered at Trieste at an altitude (tidally corrected) of -1.9 m; a similar notch, at an altitude of -0.6, was measured by Fouache et al., (2000) along Croatian coast, but while at Trieste the Present day marine notch is lacking, along Croatian coast, instead, this notch is well carved. This should result from complex equilibrium between eustatic sea level, hydro-glacio isostasy and tectonic that must be different between Trieste and Croatian coast. The deeper submerged marine notch on limestones of Trieste is suitable with an Plio-quaternary tilting of the Carso plateau, gently dipping to NW, as illustrated by other observations by Carulli et al.,(1980). This fact may be related also to the increasing weight of the external fronts of the South-alpine chain and to the External Dinarides one. Both, characterized by strong seismic activity and consequent neotectonics effects, are rising and advancing not far from Trieste. In a tectonically stable zone as Gaeta (Central Tyrrhenian sea) the submerged cliff immediately belove the present day marine notch was monitored (Antonioli, 1989) and was discovered a smoothed morphology similar to a very large marine notch. Such composite morphology made off from two different notches (in 4-5 meters of submerged cliff) is present also as fossil and related to

  3. Elevated nutrients change bacterial community composition and connectivity: high throughput sequencing of young marine biofilms.

    PubMed

    Lawes, Jasmin C; Neilan, Brett A; Brown, Mark V; Clark, Graeme F; Johnston, Emma L

    2016-01-01

    Biofilms are integral to many marine processes but their formation and function may be affected by anthropogenic inputs that alter environmental conditions, including fertilisers that increase nutrients. Density composition and connectivity of biofilms developed in situ (under ambient and elevated nutrients) were compared using 454-pyrosequencing of the 16S gene. Elevated nutrients shifted community composition from bacteria involved in higher processes (eg Pseudoalteromonas spp. invertebrate recruitment) towards more nutrient-tolerant bacterial species (eg Terendinibacter sp.). This may enable the persistence of biofilm communities by increasing resistance to nutrient inputs. A core biofilm microbiome was identified (predominantly Alteromonadales and Oceanospirillales) and revealed shifts in abundances of core microbes that could indicate enrichment by fertilisers. Fertiliser decreased density and connectivity within biofilms indicating that associations were disrupted perhaps via changes to energetic allocations within the core microbiome. Density composition and connectivity changes suggest nutrients can affect the stability and function of these important marine communities.

  4. Variability in biomass yields of large marine ecosystems (LMEs) during climate change

    SciTech Connect

    Sherman, K. )

    1993-06-01

    Results of ecosystem studies relating to variations in biomass yields are examined in relation to principle driving forces including climate change, coastal pollution, habitat degradation, and overexploitation of living marine resources. Among the ecosystems compared with regard to the different prime driving forces, affecting sustainability of biomass yields, are the Black Sea, the Baltic Sea, the Barents Sea, Kuroshio Current, California Current, Great Barrier Reef, Gulf of Mexico, Yellow Sea, Icelandic Shelf, and Northeast US Shelf ecosystems. The designation and management of large marine ecosystems (LMEs) is, at present, an evolving scientific and geopolitical process. Sufficient progress has been made to allow for useful comparisons among different processes influencing large-scale changes in the biomass yields of LMEs. The most severely impacted LMEs are off the coasts of the continents.

  5. Rocky desertification in Southwest China: Impacts, causes, and restoration

    NASA Astrophysics Data System (ADS)

    Jiang, Zhongcheng; Lian, Yanqing; Qin, Xiaoqun

    2014-05-01

    Rocky desertification, which is relatively less well known than desertification, refers to the processes and human activities that transform a karst area covered by vegetation and soil into a rocky landscape. It has occurred in various countries and regions, including the European Mediterranean and Dinaric Karst regions of the Balkan Peninsula, Southwest China on a large scale, and alarmingly, even in tropical rainforests such as Haiti and Barbados, and has had tremendous negative impacts to the environment and social and economic conditions at local and regional scales. The goal of this paper is to provide a thorough review of the impacts, causes, and restoration measures of rocky desertification based on decades of studies in the southwest karst area of China and reviews of studies in Europe and other parts of the world. The low soil formation rate and high permeability of carbonate rocks create a fragile and vulnerable environment that is susceptible to deforestation and soil erosion. Other natural processes related to hydrology and ecology could exacerbate rocky desertification. However, disturbances from a wide variety of human activities are ultimately responsible for rocky desertification wherever it has occurred. This review shows that reforestation can be successful in Southwest China and even in the Dinaric Karst region when the land, people, water, and other resources are managed cohesively. However, new challenges may arise as more frequent droughts and extreme floods induced by global climate change and variability may slow the recovery process or even expand rocky desertification. This review is intended to bring attention to this challenging issue and provide information needed to advance research and engineering practices to combat rocky desertification and to aid in sustainable development.

  6. GENIES/SimCLIM Tools to Support Climate Change Information and Marine Resource Management

    NASA Astrophysics Data System (ADS)

    Li, Y.; Urich, P.; Yin, C.; Kouwenhoven, P.; CLIMsystems Team

    2013-05-01

    Climate change will significantly impact the global environment, and the faster the change, the greater the risk of damage. The natural environment will be assaulted by increases in sea surface temperature and changes in the biogeochemical cycles of ocean ecosystems. Marine resource managers have begun to realize that the projected impacts of climate change in coastal and marine environments are full of uncertainties, creating enormous challenges when it comes to climate change response planning. CMIP5 GCMs produced a large amount of climate and ocean biogeochemical data for different climate change scenarios, which can provide indispensable information for marine resource planning and decision making. However, for end users, climate and ocean information needs to be processed to make it usable while applying robust scientific methods to make that processing acceptable. SimCLIM/GENIES software provides a comprehensive climate information, data management, and impact assessment platform. The software system consists of historical data and projections for atmospheric and oceanic variables, including air-temperature, precipitation, wind speed, sea surface temperature, ocean primary production, pH, pCO2, DIO, and DIC, with the potential for other data layers. These data are pre-processed using different downscaling and pattern scaling approaches, and then stored in a compact format with a very high compression ratio, which makes them more transferable. Users can carry out statistical and ensemble analyses with the software in order to better understand uncertainties. Within the software system, historical climate data, a climate change scenario generator, and impact assessment tools are all integrated into a single platform. They are policy-maker and end-user oriented and present climate information in a friendly and easily understandable manner with excellent spatial visualization tools. Moreover, the system provided and released an ArcGIS/marine add-in, which allows

  7. The Rocky Planet Survey

    NASA Astrophysics Data System (ADS)

    Fischer, Debra

    In direct support of the NASA Origins program, we propose the Rocky Planet Survey, a high cadence exoplanet search of sixty late G and K dwarf stars using the CHIRON spectrometer, which we built and commissioned at CTIO. CHIRON operates in two high- resolution modes (R=90,000 and R=120,000) and has a demonstrated precision of better than 1 m s-1. We are contributing 200 nights of telescope time for the next three years, for the excellent phase coverage needed to carry out this work. We have developed simulation software to optimize scheduling of observations to suppress aliases and quickly extract dynamical signals. Our science objectives are to (1) provide a statistical assessment of planet occurrence as a function of decreasing mass in the range of parameter space 3 < Msini < 30 MEARTH for orbital periods up to 50 days, (2) to determine the fraction of low mass planets in multi-planet architectures, and (3) detect planets with Msini < 3 MEARTH in orbital periods shorter than ~20 days. In addition to the science objectives, we intend to push the frontiers of extreme precision Doppler measurements to keep the U.S. competitive with the next generation of European Doppler spectroscopy (ESPRESSO on the VLT). Our team has significant expertise in optical design, fiber coupling, raw extraction, barycentric velocity corrections, and Doppler analysis. The proposed work includes a new optimal extraction algorithm, with the optical designers and software engineers working together on the 2-D PSF description needed for a proper row-by-row extraction and calibration. We will also develop and test upgrades to the barycentric correction code and improvements in the Doppler code that take advantage of stability in the dispersion solution, afforded by a new vacuum-enclosed grating upgrade (scheduled for November 2011). We will test use of emission wavelength calibrations to extend the iodine (absorption) wavelength calibration that we currently use to prepare for eventual use of

  8. Effects of Land Use Change on Tropical Coastal Systems are Exacerbated by the Decline of Marine Mega-Herbivores

    NASA Astrophysics Data System (ADS)

    Lamers, L. P.; Christianen, M. J.; Govers, L. L.; Kiswara, W.; Bouma, T.; Roelofs, J. G.; Van Katwijk, M. M.

    2011-12-01

    Land use changes in tropical regions such as deforestation, mining activities, and shrimp farming, not only affect freshwater and terrestrial ecosystems, but also have a strong impact on coastal marine ecosystems. The increased influx of sediments and nutrients affects these ecosystems in multiple ways. Seagrass meadows that line coastal marine ecosystems provide important ecosystem services, e.g. sediment trapping, coastal protection and fisheries. Based on studies in East Kalimantan (Indonesia) we have shown that seagrass meadow parameters may provide more reliable indicators of land use change than the sampling of either marine sediments or water quality chemical parameters. Observations of changes in ecosystem functioning are particularly valuable for those areas where flux values are lacking and rapid surveys are needed. Time series of estuarine seagrass transects can show not only the intensity, but also the radius of action of land use change on coastal marine systems. Marine mega-herbivores pose a strong top-down control in seagrass ecosystems. We will provide a conceptual model, based on experimental evidence, to show that the global decline of marine mega-herbivore populations (as a result of large-scale poaching) may decrease the resilience of seagrass systems to increased anthropogenic forcing including land use changes. These outcomes not only urge the need for better regulation of land use change, but also for the establishment of marine protected areas (MPA's) in tropical coastal regions.

  9. High latitude changes in ice dynamics and their impact on polar marine ecosystems.

    PubMed

    Moline, Mark A; Karnovsky, Nina J; Brown, Zachary; Divoky, George J; Frazer, Thomas K; Jacoby, Charles A; Torres, Joseph J; Fraser, William R

    2008-01-01

    Polar regions have experienced significant warming in recent decades. Warming has been most pronounced across the Arctic Ocean Basin and along the Antarctic Peninsula, with significant decreases in the extent and seasonal duration of sea ice. Rapid retreat of glaciers and disintegration of ice sheets have also been documented. The rate of warming is increasing and is predicted to continue well into the current century, with continued impacts on ice dynamics. Climate-mediated changes in ice dynamics are a concern as ice serves as primary habitat for marine organisms central to the food webs of these regions. Changes in the timing and extent of sea ice impose temporal asynchronies and spatial separations between energy requirements and food availability for many higher trophic levels. These mismatches lead to decreased reproductive success, lower abundances, and changes in distribution. In addition to these direct impacts of ice loss, climate-induced changes also facilitate indirect effects through changes in hydrography, which include introduction of species from lower latitudes and altered assemblages of primary producers. Here, we review recent changes and trends in ice dynamics and the responses of marine ecosystems. Specifically, we provide examples of ice-dependent organisms and associated species from the Arctic and Antarctic to illustrate the impacts of the temporal and spatial changes in ice dynamics.

  10. Impact of climate change on marine pelagic phenology and trophic mismatch.

    PubMed

    Edwards, Martin; Richardson, Anthony J

    2004-08-19

    Phenology, the study of annually recurring life cycle events such as the timing of migrations and flowering, can provide particularly sensitive indicators of climate change. Changes in phenology may be important to ecosystem function because the level of response to climate change may vary across functional groups and multiple trophic levels. The decoupling of phenological relationships will have important ramifications for trophic interactions, altering food-web structures and leading to eventual ecosystem-level changes. Temperate marine environments may be particularly vulnerable to these changes because the recruitment success of higher trophic levels is highly dependent on synchronization with pulsed planktonic production. Using long-term data of 66 plankton taxa during the period from 1958 to 2002, we investigated whether climate warming signals are emergent across all trophic levels and functional groups within an ecological community. Here we show that not only is the marine pelagic community responding to climate changes, but also that the level of response differs throughout the community and the seasonal cycle, leading to a mismatch between trophic levels and functional groups.

  11. Impacts of climate change on marine ecosystem production in societies dependent on fisheries

    NASA Astrophysics Data System (ADS)

    Barange, M.; Merino, G.; Blanchard, J. L.; Scholtens, J.; Harle, J.; Allison, E. H.; Allen, J. I.; Holt, J.; Jennings, S.

    2014-03-01

    Growing human populations and changing dietary preferences are increasing global demands for fish, adding pressure to concerns over fisheries sustainability. Here we develop and link models of physical, biological and human responses to climate change in 67 marine national exclusive economic zones, which yield approximately 60% of global fish catches, to project climate change yield impacts in countries with different dependencies on marine fisheries. Predicted changes in fish production indicate increased productivity at high latitudes and decreased productivity at low/mid latitudes, with considerable regional variations. With few exceptions, increases and decreases in fish production potential by 2050 are estimated to be <10% (mean +3.4%) from present yields. Among the nations showing a high dependency on fisheries, climate change is predicted to increase productive potential in West Africa and decrease it in South and Southeast Asia. Despite projected human population increases and assuming that per capita fish consumption rates will be maintained, ongoing technological development in the aquaculture industry suggests that projected global fish demands in 2050 could be met, thus challenging existing predictions of inevitable shortfalls in fish supply by the mid-twenty-first century. This conclusion, however, is contingent on successful implementation of strategies for sustainable harvesting and effective distribution of wild fish products from nations and regions with a surplus to those with a deficit. Changes in management effectiveness and trade practices will remain the main influence on realized gains or losses in global fish production.

  12. The Effects of Changing Sea Ice on Marine Mammals and Their Hunters in Northern Alaska

    NASA Astrophysics Data System (ADS)

    Huntington, H.; Quakenbush, L.; Nelson, M.

    2015-12-01

    Marine mammals are important sources of food for indigenous residents of northern Alaska. Changing sea ice patterns affect the animals themselves as well as access by hunters. Documenting the traditional knowledge of Iñupiaq and Yupik hunters concerning marine mammals and sea ice makes accessible a wide range of information and insight relevant to ecological understanding, conservation action, and the regulation of human activity. We interviewed hunters in villages from northern Bering Sea to the Beaufort Sea, focusing on bowhead whales, walrus, and ice seals. Hunters reported extensive changes in sea ice, with resulting effects on the timing of marine mammal migrations, the distribution and behavior of the animals, and the efficacy of certain hunting methods, for example the difficulty of finding ice thick enough to support a bowhead whale for butchering. At the same time, hunters acknowledged impacts and potential impacts from changing technology such as more powerful outboard engines and from industrial activity such as shipping and oil and gas development. Hunters have been able to adapt to some changes, for example by hunting bowhead whales in fall as well as spring on St. Lawrence Island, or by focusing their hunt in a shorter period in Nuiqsut to accommodate work schedules and worse weather. Other changes, such as reduced availability of ice seals due to rapid retreat of pack ice after spring break-up, continue to defy easy responses. Continued environmental changes, increased disturbance from human activity, and the introduction of new regulations for hunting may further challenge the ability of hunters to provide food as they have done to date, though innovation and flexibility may also provide new sources of adaptation.

  13. Invasive symbiont bearing (and other) foraminifera altering the community structure of eastern Mediterranean rocky reefs environments

    NASA Astrophysics Data System (ADS)

    Hyams-Kaphzan, Orit; Perelis Grossowicz, Lydia; Almogi-Labin, Ahuva

    2015-04-01

    The rocky reefs of the Israeli eastern Mediterranean shelf constitute a highly diverse marine ecosystem rich in macroalgae and calcareous organisms. The benthic foraminiferal community living in this ecosystem is rapidly changing due to massive invasion of symbiont bearing foraminifera (SBF) as well as other foraminiferal species of tropical origin. This trend facilitated by the ongoing increase in temperature enables more tropical species to adjust to the eastern Mediterranean habitats. In order to document the status of the benthic foraminiferal community structure rocky reefs at Akhziv (AK) and Carmel Head (CH), northern Israel were sampled by scuba diving. Different macroalgae species, including invasive ones, accommodating the live epiphytic benthic foraminifera were sampled twice a year at AK and in each season at CH in three depth intervals between 5-20 m, during 2013-4. The numerical abundance of the group ranges between 170-3500 #/10cc (wet macroalgae volume) without any significant difference in standing stocks within regions, water depths or macroalgae preference. In total 77 benthic foraminiferal species were identified 71 in CH and only 43 at AK. Species richness per site varied between 3 and 42 with higher values at CH. 25% of all species were aliens, mostly Lessepsian, that comprise on average 70% - 84% of the numerical abundance of AK and CH respectively. Cluster analysis using benthic foraminifera relative abundance data did not correlate with the different macroalgae species, water depths or seasonality, indicating that the foraminiferal community in the two regions is quite homogenous. Amphistegina lobifera a Lessepsian migrant is by far the most common species on the Israeli rocky reefs occurring in all samples and comprising 18-93% of the foraminiferal community. Heterostegina depressa behaves similarly to A. lobifera though it occurs in lower numbers. Pararotalia calcariformata, a recently arriving SBF occupies mainly shallow water sites at CH

  14. Understanding the role of wildland fire, insects, and disease in predicting climate change effects on whitebark pine: Simulating vegetation, disturbance, and climate dynamics in a northern Rocky Mountain landscape

    NASA Astrophysics Data System (ADS)

    Keane, R. E.; Loehman, R.

    2010-12-01

    Climate changes are projected to profoundly influence vegetation patterns and community compositions, either directly through increased species mortality and shifts in species distributions, or indirectly through disturbance dynamics such as increased wildfire activity and extent, shifting fire regimes, and pathogenesis. High-elevation landscapes have been shown to be particularly sensitive to climatic change, and are likely to experience significant impacts under predicted future climate change conditions. Whitebark pine (Pinus albicaulis), a high-elevation five-needle pine species that is important for snowpack retention, resource provision, and other ecosystem services in alpine environments in the northern Rocky Mountains, is particularly sensitive to an interacting complex of disturbances - climatic change, altered fire regimes, white-pine blister rust, and mountain pine beetles - that have already caused major changes in species distribution and density. Further changes in abiotic and biotic conditions will likely pose additional threats to the success of this keystone alpine tree species. We used the mechanistic simulation model Fire-BGCv2 to assess potential interacting effects of climate changes, pathogens, and wildfire on the distribution and density of whitebark pine in a high-elevation watershed in Glacier National Park, Montana, USA. The FireBGCv2 modeling platform is uniquely structured to address questions of future species distribution in response to interacting disturbance agents; further, we integrated a range of potential future climate conditions derived from downscaled Global Circulation Models to examine multiple potential future climatic contexts. Our results show that the distribution of whitebark pine is severely reduced under potential future climates, and that increased fire frequency and severity resulting from warmer, drier conditions further reduces the presence of the species on the simulation landscape. Simulation model results

  15. Effects of sex change on the implications of marine reserves for fisheries.

    PubMed

    Chan, Neil C S; Connolly, Sean R; Mapstone, Bruce D

    2012-04-01

    Marine reserves have become widely used in biodiversity conservation and are increasingly proposed as fisheries management tools. Previous modeling studies have found that reserves may increase or decrease yields, depending on local environmental conditions and on the specific life-history traits of the fishery species. Sex-changing (female-to-male) fish are targets of some of the most important commercial and recreational fisheries in the world. The potential for disproportionate removal of the larger, older sex of such species requires new theory to facilitate our understanding of how reserves will affect the yields of surrounding fisheries, relative to fishes with separate sexes. We investigated this question by modeling the effects of marine reserves on a non-sex-changing and a sex-changing population. We used demographic parameter estimates for the common coral trout as a baseline, and we conducted extensive sensitivity analyses to determine how sustainable yields of sex-changing species are likely to be affected by reserves across a broad range of life-history parameters. Our findings indicate that fisheries for sex-changing species are unlikely to receive the same yield-enhancing benefit that non-sex-changing fisheries enjoy from marine reserves, and that often reserves tend to reduce sustainable yields for a given overall population size. Specifically, the increased egg production and high fertilization success within reserves is more than offset by the reduced egg production and fertilization success in the fished areas, relative to a system in which fishing mortality is distributed more evenly over the entire system. A key reason for this appears to be that fertilization success is reduced, on average, when males are unevenly distributed among subpopulations, as is the case when reserves are present. These findings suggests that, for sex-changing populations, reserves are more suited to rebuilding overfished populations and sustaining fishery viability

  16. Rocky Mountain spotted fever, Colombia.

    PubMed

    Hidalgo, Marylin; Orejuela, Leonora; Fuya, Patricia; Carrillo, Pilar; Hernandez, Jorge; Parra, Edgar; Keng, Colette; Small, Melissa; Olano, Juan P; Bouyer, Donald; Castaneda, Elizabeth; Walker, David; Valbuena, Gustavo

    2007-07-01

    We investigated 2 fatal cases of Rocky Mountain spotted fever that occurred in 2003 and 2004 near the same locality in Colombia where the disease was first reported in the 1930s. A retrospective serosurvey of febrile patients showed that > 21% of the serum samples had antibodies aaainst spotted fever group rickettsiae.

  17. Rocky Mountain spotted fever, Panama.

    PubMed

    Estripeaut, Dora; Aramburú, María Gabriela; Sáez-Llorens, Xavier; Thompson, Herbert A; Dasch, Gregory A; Paddock, Christopher D; Zaki, Sherif; Eremeeva, Marina E

    2007-11-01

    We describe a fatal pediatric case of Rocky Mountain spotted fever in Panama, the first, to our knowledge, since the 1950s. Diagnosis was established by immunohistochemistry, PCR, and isolation of Rickettsia rickettsii from postmortem tissues. Molecular typing demonstrated strong relatedness of the isolate to strains of R. rickettsii from Central and South America.

  18. Response of a marine ice sheet to changes at the grounding line

    SciTech Connect

    Van der Veen, C.J.

    1985-01-01

    A numerical model was designed to study the stability of a marine ice sheet, and used to do some basic experiments. The ice-shelf/ice-sheet interaction enters through the flow law in which the longitudinal stress is also taken into account. Instead of applying the model to some (measured) profile and showing that this is unstable (as is common practice in other studies), an attempt is made to simulate a whole cycle of growth and retreat of a marine ice sheet, although none of the model sheets is particularly sensitive to changes in environmental conditions. The question as to what might happen to the West Antarctic Ice Sheet in the near future when a climatic warming can be expected as a result of the CO/sub 2/ effect, seems to be open for discussion again. From the results presented in this paper one can infer that a collapse, caused by increased melting on the ice shelves, is not very likely.

  19. Changes in the water quality conditions of Kuwait's marine waters: Long term impacts of nutrient enrichment.

    PubMed

    Devlin, M J; Massoud, M S; Hamid, S A; Al-Zaidan, A; Al-Sarawi, H; Al-Enezi, M; Al-Ghofran, L; Smith, A J; Barry, J; Stentiford, G D; Morris, S; da Silva, E T; Lyons, B P

    2015-11-30

    This work analyses a 30 year water quality data set collated from chemical analyses of Kuwait's marine waters. Spatial patterns across six sites in Kuwait Bay and seven sites located in the Arabian Gulf are explored and discussed in terms of the changing influences associated with point and diffuse sources. Statistical modelling demonstrated significant increases for dissolved nutrients over the time period. Kuwait marine waters have been subject to inputs from urban development, untreated sewage discharges and decreasing river flow from the Shatt al-Arab River. Chlorophyll biomass showed a small but significant reduction; the high sewage content of the coastal waters from sewage discharges likely favouring the presence of smaller phytoplankton taxa. This detailed assessment of temporal data of the impacts of sewage inputs into Kuwait's coastal waters establishes an important baseline permitting future assessments to be made as sewage is upgraded, and the river continues to be extracted upstream.

  20. Organism activity levels predict marine invertebrate survival during ancient global change extinctions.

    PubMed

    Clapham, Matthew E

    2017-04-01

    Multistressor global change, the combined influence of ocean warming, acidification, and deoxygenation, poses a serious threat to marine organisms. Experimental studies imply that organisms with higher levels of activity should be more resilient, but testing this prediction and understanding organism vulnerability at a global scale, over evolutionary timescales, and in natural ecosystems remain challenging. The fossil record, which contains multiple extinctions triggered by multistressor global change, is ideally suited for testing hypotheses at broad geographic, taxonomic, and temporal scales. Here, I assess the importance of activity level for survival of well-skeletonized benthic marine invertebrates over a 100-million-year-long interval (Permian to Jurassic periods) containing four global change extinctions, including the end-Permian and end-Triassic mass extinctions. More active organisms, based on a semiquantitative score incorporating feeding and motility, were significantly more likely to survive during three of the four extinction events (Guadalupian, end-Permian, and end-Triassic). In contrast, activity was not an important control on survival during nonextinction intervals. Both the end-Permian and end-Triassic mass extinctions also triggered abrupt shifts to increased dominance by more active organisms. Although mean activity gradually returned toward pre-extinction values, the net result was a permanent ratcheting of ecosystem-wide activity to higher levels. Selectivity patterns during ancient global change extinctions confirm the hypothesis that higher activity, a proxy for respiratory physiology, is a fundamental control on survival, although the roles of specific physiological traits (such as extracellular pCO2 or aerobic scope) cannot be distinguished. Modern marine ecosystems are dominated by more active organisms, in part because of selectivity ratcheting during these ancient extinctions, so on average may be less vulnerable to global change

  1. Environmental forcing and Southern Ocean marine predator populations: effects of climate change and variability.

    PubMed

    Trathan, P N; Forcada, J; Murphy, E J

    2007-12-29

    The Southern Ocean is a major component within the global ocean and climate system and potentially the location where the most rapid climate change is most likely to happen, particularly in the high-latitude polar regions. In these regions, even small temperature changes can potentially lead to major environmental perturbations. Climate change is likely to be regional and may be expressed in various ways, including alterations to climate and weather patterns across a variety of time-scales that include changes to the long interdecadal background signals such as the development of the El Niño-Southern Oscillation (ENSO). Oscillating climate signals such as ENSO potentially provide a unique opportunity to explore how biological communities respond to change. This approach is based on the premise that biological responses to shorter-term sub-decadal climate variability signals are potentially the best predictor of biological responses over longer time-scales. Around the Southern Ocean, marine predator populations show periodicity in breeding performance and productivity, with relationships with the environment driven by physical forcing from the ENSO region in the Pacific. Wherever examined, these relationships are congruent with mid-trophic-level processes that are also correlated with environmental variability. The short-term changes to ecosystem structure and function observed during ENSO events herald potential long-term changes that may ensue following regional climate change. For example, in the South Atlantic, failure of Antarctic krill recruitment will inevitably foreshadow recruitment failures in a range of higher trophic-level marine predators. Where predator species are not able to accommodate by switching to other prey species, population-level changes will follow. The Southern Ocean, though oceanographically interconnected, is not a single ecosystem and different areas are dominated by different food webs. Where species occupy different positions in

  2. The influence of historical climate changes on Southern Ocean marine predator populations: a comparative analysis.

    PubMed

    Younger, Jane L; Emmerson, Louise M; Miller, Karen J

    2016-02-01

    The Southern Ocean ecosystem is undergoing rapid physical and biological changes that are likely to have profound implications for higher-order predators. Here, we compare the long-term, historical responses of Southern Ocean predators to climate change. We examine palaeoecological evidence for changes in the abundance and distribution of seabirds and marine mammals, and place these into context with palaeoclimate records in order to identify key environmental drivers associated with population changes. Our synthesis revealed two key factors underlying Southern Ocean predator population changes; (i) the availability of ice-free ground for breeding and (ii) access to productive foraging grounds. The processes of glaciation and sea ice fluctuation were key; the distributions and abundances of elephant seals, snow petrels, gentoo, chinstrap and Adélie penguins all responded strongly to the emergence of new breeding habitat coincident with deglaciation and reductions in sea ice. Access to productive foraging grounds was another limiting factor, with snow petrels, king and emperor penguins all affected by reduced prey availability in the past. Several species were isolated in glacial refugia and there is evidence that refuge populations were supported by polynyas. While the underlying drivers of population change were similar across most Southern Ocean predators, the individual responses of species to environmental change varied because of species specific factors such as dispersal ability and environmental sensitivity. Such interspecific differences are likely to affect the future climate change responses of Southern Ocean marine predators and should be considered in conservation plans. Comparative palaeoecological studies are a valuable source of long-term data on species' responses to environmental change that can provide important insights into future climate change responses. This synthesis highlights the importance of protecting productive foraging grounds

  3. Climate change in the oceans: evolutionary versus phenotypically plastic responses of marine animals and plants

    PubMed Central

    Reusch, Thorsten B H

    2014-01-01

    I summarize marine studies on plastic versus adaptive responses to global change. Due to the lack of time series, this review focuses largely on the potential for adaptive evolution in marine animals and plants. The approaches were mainly synchronic comparisons of phenotypically divergent populations, substituting spatial contrasts in temperature or CO2 environments for temporal changes, or in assessments of adaptive genetic diversity within populations for traits important under global change. The available literature is biased towards gastropods, crustaceans, cnidarians and macroalgae. Focal traits were mostly environmental tolerances, which correspond to phenotypic buffering, a plasticity type that maintains a functional phenotype despite external disturbance. Almost all studies address coastal species that are already today exposed to fluctuations in temperature, pH and oxygen levels. Recommendations for future research include (i) initiation and analyses of observational and experimental temporal studies encompassing diverse phenotypic traits (including diapausing cues, dispersal traits, reproductive timing, morphology) (ii) quantification of nongenetic trans-generational effects along with components of additive genetic variance (iii) adaptive changes in microbe–host associations under the holobiont model in response to global change (iv) evolution of plasticity patterns under increasingly fluctuating environments and extreme conditions and (v) joint consideration of demography and evolutionary adaptation in evolutionary rescue approaches. PMID:24454551

  4. Pressures on the marine environment and the changing climate of ocean biogeochemistry.

    PubMed

    Rees, Andrew P

    2012-12-13

    The oceans are under pressure from human activities. Following 250 years of industrial activity, effects are being seen at the cellular through to regional and global scales. The change in atmospheric CO(2) from 280 ppm in pre-industrial times to 392 ppm in 2011 has contributed to the warming of the upper 700 m of the ocean by approximately 0.1°C between 1961 and 2003, to changes in sea water chemistry, which include a pH decrease of approximately 0.1, and to significant decreases in the sea water oxygen content. In parallel with these changes, the human population has been introducing an ever-increasing level of nutrients into coastal waters, which leads to eutrophication, and by 2008 had resulted in 245,000 km(2) of severely oxygen-depleted waters throughout the world. These changes are set to continue for the foreseeable future, with atmospheric CO(2) predicted to reach 430 ppm by 2030 and 750 ppm by 2100. The cycling of biogeochemical elements has proved sensitive to each of these effects, and it is proposed that synergy between stressors may compound this further. The challenge, within the next few decades, for the marine science community, is to elucidate the scope and extent that biological processes can adapt or acclimatize to a changing chemical and physical marine environment.

  5. Climate change in the oceans: evolutionary versus phenotypically plastic responses of marine animals and plants.

    PubMed

    Reusch, Thorsten B H

    2014-01-01

    I summarize marine studies on plastic versus adaptive responses to global change. Due to the lack of time series, this review focuses largely on the potential for adaptive evolution in marine animals and plants. The approaches were mainly synchronic comparisons of phenotypically divergent populations, substituting spatial contrasts in temperature or CO2 environments for temporal changes, or in assessments of adaptive genetic diversity within populations for traits important under global change. The available literature is biased towards gastropods, crustaceans, cnidarians and macroalgae. Focal traits were mostly environmental tolerances, which correspond to phenotypic buffering, a plasticity type that maintains a functional phenotype despite external disturbance. Almost all studies address coastal species that are already today exposed to fluctuations in temperature, pH and oxygen levels. Recommendations for future research include (i) initiation and analyses of observational and experimental temporal studies encompassing diverse phenotypic traits (including diapausing cues, dispersal traits, reproductive timing, morphology) (ii) quantification of nongenetic trans-generational effects along with components of additive genetic variance (iii) adaptive changes in microbe-host associations under the holobiont model in response to global change (iv) evolution of plasticity patterns under increasingly fluctuating environments and extreme conditions and (v) joint consideration of demography and evolutionary adaptation in evolutionary rescue approaches.

  6. Immunoendocrine alterations following Marine Corps Martial Arts training are associated with changes in moral cognitive processes.

    PubMed

    Siedlik, Jacob A; Deckert, Jake A; Clopton, Aaron W; Gigliotti, Nicole; Chan, Marcia A; Benedict, Stephen H; Herda, Trent J; Gallagher, Philip M; Vardiman, John P

    2016-02-01

    Combined physical and psychological stress events have been associated with exacerbated endocrine responses and increased alterations in immune cell trafficking when compared to exercise stress alone. Military training programs are rigorous in nature and often purposefully delivered in environments combining high levels of both physical and mental stress. The objective of this study was to assess physiological and cognitive changes following U.S. Marine Corps Martial Arts training. Seven active-duty, male Marines were observed during a typical Marine Corps Martial Arts training session. Immune parameters, including immunomodulatory cytokines, and hormone concentrations were determined from blood samples obtained at baseline, immediately post training (IP) and at 15min intervals post-training to 1h (R15, R30, R45, R60). Assessments of cognitive moral functioning (moral judgment and intent) were recorded at intervals during recovery. There were significant fluctuations in immunoendocrine parameters. Peak endocrine measures were observed within the IP-R15 time interval. Distributions of circulating immune cells were significantly altered with neutrophils and all lymphocyte subsets elevated at IP. IFN-γ and IL-17a exhibited small, non-significant, parallel increases over the recovery period. Moral functioning was informed by different social identities during the recovery resulting in changes in moral decision-making. These data demonstrate that the Marine Corps Martial Arts Program induces significant alterations in lymphocyte and leukocyte distributions, but does not shift the balance of Th1/Th2 cytokines or induce a systemic inflammatory response. The program does, however, induce alterations in moral decision-making ability associated with the observed endocrine responses, even suggesting a potential interaction between one's social identities and endocrine responses upon moral decision-making.

  7. Large variations in the Holocene marine radiocarbon reservoir effect reflect ocean circulation and climatic changes

    NASA Astrophysics Data System (ADS)

    Hua, Quan; Webb, Gregory E.; Zhao, Jian-xin; Nothdurft, Luke D.; Lybolt, Matthew; Price, Gilbert J.; Opdyke, Bradley N.

    2015-07-01

    Accurate radiocarbon dating of marine samples requires knowledge of the marine radiocarbon reservoir effect. This effect for a particular site/region is generally assumed constant through time when calibrating marine 14C ages. However, recent studies have shown large temporal variations of several hundred to a couple of thousand years in this effect for a number of regions during the late Quaternary and Holocene. Here we report marine radiocarbon reservoir correction (ΔR) for Heron Reef and Moreton Bay in southwestern (SW) Pacific for the last 8 ka derived from 14C analysis of 230Th-dated corals. Most of our ΔR for the last ∼5.4 ka agree well with their modern value, but large ΔR variability of ∼410 yr (from trough to peak) with possible decadal/centennial fluctuations is evident for the period ∼5.4-8 ka. The latter time interval also has significant variations with similar features in previously published ΔR values for other sites in the Pacific, including southern Peru-northern Chile in southeastern (SE) Pacific, the South China Sea, Vanuatu and Papua New Guinea, with the largest magnitude of ∼920 yr from SE Pacific. The mechanisms for these large ΔR variations across the Pacific during the mid-Holocene are complex processes involving (1) changes in the quantity and 14C content of upwelled waters in tropical east Pacific (TEP) (frequency and intensity of ocean upwelling in the TEP, and contribution of Subantarctic Mode Water to the upwelled waters, which is influenced by the intensity and position of southern westerly winds), and (2) variations in ocean circulation associated with climate change (La Niña/El Niño conditions, intensity of easterly trade winds, positions of the Intertropical Convergence Zone and the South Pacific Convergence Zone), which control the spreading of the older upwelled surface waters in the TEP to the western sites. Our results imply the need for employing temporal changes in ΔR values, instead of constant (modern) values

  8. Spatial and body-size dependent response of marine pelagic communities to projected global climate change.

    PubMed

    Lefort, Stelly; Aumont, Olivier; Bopp, Laurent; Arsouze, Thomas; Gehlen, Marion; Maury, Olivier

    2015-01-01

    Temperature, oxygen, and food availability directly affect marine life. Climate models project a global warming of the ocean's surface (~+3 °C), a de-oxygenation of the ocean's interior (~-3%) and a decrease in total marine net primary production (~-8%) under the 'business as usual' climate change scenario (RCP8.5). We estimated the effects of these changes on biological communities using a coupled biogeochemical (PISCES)--ecosystems (APECOSM) model forced by the physical outputs of the last generation of the IPSL-CM Earth System Model. The APECOSM model is a size-structured bio-energetic model that simulates the 3D dynamical distributions of three interactive pelagic communities (epipelagic, mesopelagic, and migratory) under the effects of multiple environmental factors. The PISCES-APECOSM model ran from 1850 to 2100 under historical forcing followed by RCP8.5. Our RCP8.5 simulation highlights significant changes in the spatial distribution, biomass, and maximum body-size of the simulated pelagic communities. Biomass and maximum body-size increase at high latitude over the course of the century, reflecting the capacity of marine organisms to respond to new suitable environment. At low- and midlatitude, biomass and maximum body-size strongly decrease. In those regions, large organisms cannot maintain their high metabolic needs because of limited and declining food availability. This resource reduction enhances the competition and modifies the biomass distribution among and within the three communities: the proportion of small organisms increases in the three communities and the migrant community that initially comprised a higher proportion of small organisms is favored. The greater resilience of small body-size organisms resides in their capacity to fulfill their metabolic needs under reduced energy supply and is further favored by the release of predation pressure due to the decline of large organisms. These results suggest that small body-size organisms might be

  9. Climate change and the marine ecosystem of the western Antarctic Peninsula.

    PubMed

    Clarke, Andrew; Murphy, Eugene J; Meredith, Michael P; King, John C; Peck, Lloyd S; Barnes, David K A; Smith, Raymond C

    2007-01-29

    The Antarctic Peninsula is experiencing one of the fastest rates of regional climate change on Earth, resulting in the collapse of ice shelves, the retreat of glaciers and the exposure of new terrestrial habitat. In the nearby oceanic system, winter sea ice in the Bellingshausen and Amundsen seas has decreased in extent by 10% per decade, and shortened in seasonal duration. Surface waters have warmed by more than 1 K since the 1950s, and the Circumpolar Deep Water (CDW) of the Antarctic Circumpolar Current has also warmed. Of the changes observed in the marine ecosystem of the western Antarctic Peninsula (WAP) region to date, alterations in winter sea ice dynamics are the most likely to have had a direct impact on the marine fauna, principally through shifts in the extent and timing of habitat for ice-associated biota. Warming of seawater at depths below ca 100 m has yet to reach the levels that are biologically significant. Continued warming, or a change in the frequency of the flooding of CDW onto the WAP continental shelf may, however, induce sublethal effects that influence ecological interactions and hence food-web operation. The best evidence for recent changes in the ecosystem may come from organisms which record aspects of their population dynamics in their skeleton (such as molluscs or brachiopods) or where ecological interactions are preserved (such as in encrusting biota of hard substrata). In addition, a southwards shift of marine isotherms may induce a parallel migration of some taxa similar to that observed on land. The complexity of the Southern Ocean food web and the nonlinear nature of many interactions mean that predictions based on short-term studies of a small number of species are likely to be misleading.

  10. Climate change and the marine ecosystem of the western Antarctic Peninsula

    PubMed Central

    Clarke, Andrew; Murphy, Eugene J; Meredith, Michael P; King, John C; Peck, Lloyd S; Barnes, David K.A; Smith, Raymond C

    2006-01-01

    The Antarctic Peninsula is experiencing one of the fastest rates of regional climate change on Earth, resulting in the collapse of ice shelves, the retreat of glaciers and the exposure of new terrestrial habitat. In the nearby oceanic system, winter sea ice in the Bellingshausen and Amundsen seas has decreased in extent by 10% per decade, and shortened in seasonal duration. Surface waters have warmed by more than 1 K since the 1950s, and the Circumpolar Deep Water (CDW) of the Antarctic Circumpolar Current has also warmed. Of the changes observed in the marine ecosystem of the western Antarctic Peninsula (WAP) region to date, alterations in winter sea ice dynamics are the most likely to have had a direct impact on the marine fauna, principally through shifts in the extent and timing of habitat for ice-associated biota. Warming of seawater at depths below ca 100 m has yet to reach the levels that are biologically significant. Continued warming, or a change in the frequency of the flooding of CDW onto the WAP continental shelf may, however, induce sublethal effects that influence ecological interactions and hence food-web operation. The best evidence for recent changes in the ecosystem may come from organisms which record aspects of their population dynamics in their skeleton (such as molluscs or brachiopods) or where ecological interactions are preserved (such as in encrusting biota of hard substrata). In addition, a southwards shift of marine isotherms may induce a parallel migration of some taxa similar to that observed on land. The complexity of the Southern Ocean food web and the nonlinear nature of many interactions mean that predictions based on short-term studies of a small number of species are likely to be misleading. PMID:17405211

  11. Transcriptional Changes Underlying Elemental Stoichiometry Shifts in a Marine Heterotrophic Bacterium

    PubMed Central

    Chan, Leong-Keat; Newton, Ryan J.; Sharma, Shalabh; Smith, Christa B.; Rayapati, Pratibha; Limardo, Alexander J.; Meile, Christof; Moran, Mary Ann

    2012-01-01

    Marine bacteria drive the biogeochemical processing of oceanic dissolved organic carbon (DOC), a 750-Tg C reservoir that is a critical component of the global C cycle. Catabolism of DOC is thought to be regulated by the biomass composition of heterotrophic bacteria, as cells maintain a C:N:P ratio of ∼50:10:1 during DOC processing. Yet a complicating factor in stoichiometry-based analyses is that bacteria can change the C:N:P ratio of their biomass in response to resource composition. We investigated the physiological mechanisms of resource-driven shifts in biomass stoichiometry in continuous cultures of the marine heterotrophic bacterium Ruegeria pomeroyi (a member of the Roseobacter clade) under four element limitation regimes (C, N, P, and S). Microarray analysis indicated that the bacterium scavenged for alternate sources of the scarce element when cells were C-, N-, or P-limited; reworked the ratios of biomolecules when C- and P- limited; and exerted tighter control over import/export and cytoplasmic pools when N-limited. Under S limitation, a scenario not existing naturally for surface ocean microbes, stress responses dominated transcriptional changes. Resource-driven changes in C:N ratios of up to 2.5-fold and in C:P ratios of up to sixfold were measured in R. pomeroyi biomass. These changes were best explained if the C and P content of the cells was flexible in the face of shifting resources but N content was not, achieved through the net balance of different transcriptional strategies. The cellular-level metabolic trade-offs that govern biomass stoichiometry in R. pomeroyi may have implications for global carbon cycling if extendable to other heterotrophic bacteria. Strong homeostatic responses to N limitation by marine bacteria would intensify competition with autotrophs. Modification of cellular inventories in C- and P-limited heterotrophs would vary the elemental ratio of particulate organic matter sequestered in the deep ocean. PMID:22783226

  12. Climate change effects on the marine characteristics of the Aegean and Ionian Seas

    NASA Astrophysics Data System (ADS)

    Makris, Christos; Galiatsatou, Panagiota; Tolika, Konstantia; Anagnostopoulou, Christina; Kombiadou, Katerina; Prinos, Panayotis; Velikou, Kondylia; Kapelonis, Zacharias; Tragou, Elina; Androulidakis, Yannis; Athanassoulis, Gerasimos; Vagenas, Christos; Tegoulias, Ioannis; Baltikas, Vassilis; Krestenitis, Yannis; Gerostathis, Theodoros; Belibassakis, Kostantinos; Rusu, Eugen

    2016-12-01

    This paper addresses the effects of estimated climate change on the sea-surface dynamics of the Aegean and Ionian Seas (AIS). The main aim is the identification of climate change impacts on the severity and frequency of extreme storm surges and waves in areas of the AIS prone to flooding. An attempt is made to define design levels for future research on coastal protection in Greece. Extreme value analysis is implemented through a nonstationary generalized extreme value distribution function, incorporating time harmonics in its parameters, by means of statistically defined criteria. A 50-year time span analysis is adopted and changes of means and extremes are determined. A Regional Climate Model (RegCM3) is implemented with dynamical downscaling, forced by ECHAM5 fields under 20C3M historical data for the twentieth century and the SRES-A1B scenario for the twenty-first century. Storm surge and wave models (GreCSSM and SWAN, respectively) are used for marine climate simulations. Comparisons of model results with reanalysis and field data of atmospheric and hydrodynamic characteristics, respectively, are in good agreement. Our findings indicate that the dynamically downscaled RegCM3 simulation adequately reproduces the present general circulation patterns over the Mediterranean and Greece. Future changes in sea level pressure and mean wind fields are estimated to be small, yet significant for marine extremes. In general, we estimate a projected intensification of severe wave and storm surge events during the first half of the twenty-first century and a subsequent storminess attenuation leading to the resettlement of milder extreme marine events with increased prediction uncertainty in the second half of the twenty-first century.

  13. Mismatch between marine plankton range movements and the velocity of climate change

    NASA Astrophysics Data System (ADS)

    Chivers, William J.; Walne, Anthony W.; Hays, Graeme C.

    2017-02-01

    The response of marine plankton to climate change is of critical importance to the oceanic food web and fish stocks. We use a 60-year ocean basin-wide data set comprising >148,000 samples to reveal huge differences in range changes associated with climate change across 35 plankton taxa. While the range of dinoflagellates and copepods tended to closely track the velocity of climate change (the rate of isotherm movement), the range of the diatoms moved much more slowly. Differences in range shifts were up to 900 km in a recent warming period, with average velocities of range movement between 7 km per decade northwards for taxa exhibiting niche plasticity and 99 km per decade for taxa exhibiting niche conservatism. The differing responses of taxa to global warming will cause spatial restructuring of the plankton ecosystem with likely consequences for grazing pressures on phytoplankton and hence for biogeochemical cycling, higher trophic levels and biodiversity.

  14. Mismatch between marine plankton range movements and the velocity of climate change.

    PubMed

    Chivers, William J; Walne, Anthony W; Hays, Graeme C

    2017-02-10

    The response of marine plankton to climate change is of critical importance to the oceanic food web and fish stocks. We use a 60-year ocean basin-wide data set comprising >148,000 samples to reveal huge differences in range changes associated with climate change across 35 plankton taxa. While the range of dinoflagellates and copepods tended to closely track the velocity of climate change (the rate of isotherm movement), the range of the diatoms moved much more slowly. Differences in range shifts were up to 900 km in a recent warming period, with average velocities of range movement between 7 km per decade northwards for taxa exhibiting niche plasticity and 99 km per decade for taxa exhibiting niche conservatism. The differing responses of taxa to global warming will cause spatial restructuring of the plankton ecosystem with likely consequences for grazing pressures on phytoplankton and hence for biogeochemical cycling, higher trophic levels and biodiversity.

  15. Arctic Ecosystem Integrated Survey (Arctic Eis): Marine ecosystem dynamics in the rapidly changing Pacific Arctic Gateway

    NASA Astrophysics Data System (ADS)

    Mueter, Franz J.; Weems, Jared; Farley, Edward V.; Sigler, Michael F.

    2017-01-01

    Arctic Marine Ecosystems are undergoing rapid changes associated with ice loss and surface warming resulting from human activities (IPCC, 2013). The most dramatic changes include an earlier ice retreat and a longer ice-free season, particularly on Arctic inflow shelves such as the Barents Sea in the Atlantic Arctic and the northern Bering Sea and Chukchi Sea in the Pacific Arctic, the two major gateways into the Arctic (Danielson et al., 2016; Frey et al., 2015; Serreze et al., 2007; Wood et al., 2015). The retreat of Arctic sea ice has opened access to the Arctic marine environment and its resources, particularly during summer, and among other changes has brought with it increased research activities. For the Pacific Arctic region, these activities have led to several recent compendiums examining physical, biogeochemical, and biological patterns and trends in this rapidly changing environment (Arrigo, 2015, 2016; Arrigo et al., 2014; Bluhm et al., 2010; Dunton et al., 2014; Grebmeier and Maslowski, 2014; Hopcroft and Day, 2013; Moore and Stabeno, 2015).

  16. Implications of climate change for northern Canada: freshwater, marine, and terrestrial ecosystems.

    PubMed

    Prowse, Terry D; Furgal, Chris; Wrona, Fred J; Reist, James D

    2009-07-01

    Climate variability and change is projected to have significant effects on the physical, chemical, and biological components of northern Canadian marine, terrestrial, and freshwater systems. As the climate continues to change, there will be consequences for biodiversity shifts and for the ranges and distribution of many species with resulting effects on availability, accessibility, and quality of resources upon which human populations rely. This will have implications for the protection and management of wildlife, fish, and fisheries resources; protected areas; and forests. The northward migration of species and the disruption and competition from invading species are already occurring and will continue to affect marine, terrestrial, and freshwater communities. Shifting environmental conditions will likely introduce new animal-transmitted diseases and redistribute some existing diseases, affecting key economic resources and some human populations. Stress on populations of iconic wildlife species, such as the polar bear, ringed seals, and whales, will continue as a result of changes in critical sea-ice habitat interactions. Where these stresses affect economically and culturally important species, they will have significant effects on people and regional economies. Further integrated, field-based monitoring and research programs, and the development of predictive models are required to allow for more detailed and comprehensive projections of change to be made, and to inform the development and implementation of appropriate adaptation, wildlife, and habitat conservation and protection strategies.

  17. 77 FR 39402 - Safety Zone; Cleveland Yachting Club Fireworks, Lake Erie, Rocky River, OH

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-03

    ..., Chief of Waterways Management, U.S. Coast Guard Sector Buffalo; telephone 716- 843-9343, email SectorBuffaloMarineSafety@uscg.mil . If you have questions on viewing or submitting material to the docket, call... be held on Lake Erie near Rocky River, OH. The Captain of the Port Buffalo has determined...

  18. [Effects of global climate change on the ecological characteristics and biogeochemical significance of marine viruses--A review].

    PubMed

    Yang, Yunlan; Cai, Lanlan; Zhang, Rui

    2015-09-04

    As the most abundance biological agents in the oceans, viruses can influence the physiological and ecological characteristics of host cells through viral infections and lysis, and affect the nutrient and energy cycles of the marine food chain. Thus, they are the major players in the ocean biogeochemical processes. The problems caused by global climate changes, such as sea-surface warming, acidification, nutrients availability, and deoxygenation, have the potential effects on marine viruses and subsequently their ecological and biogeochemical function in the ocean. Here, we reviewed the potential impacts of global climate change on the ecological characteristics (e. g. abundance, distribution, life cycle and the host-virus interactions) and biogeochemical significance (e. g. carbon cycling) of marine viruses. We proposed that marine viruses should not be ignored in the global climate change study.

  19. Biological invasions as a component of global change in stressed marine ecosystems.

    PubMed

    Occhipinti-Ambrogi, A; Savini, D

    2003-05-01

    Biological invasions in marine environment are the lesser known aspect of global change. However, recent events which occurred in the Mediterranean Sea demonstrate that they represent a serious ecological and economical menace leading to biodiversity loss, ecosystem unbalancing, fishery and tourism impairment. In this paper we review marine bioinvasions using examples taken from the Mediterranean/Black Sea region. Particular attention is given to the environmental status of the receiving area as a fundamental pre-requisite for the colonisation success of alien species. The spread of the tropical algae belonging to the genus Caulerpa in the northwestern basin of the Mediterranean Sea has been facilitated by pre-existing conditions of instability of the Posidonia oceanica endemic ecosystem in relation to stress of both natural and anthropogenic origin. Human interventions caused long-term modification in the Black Sea environment, preparing a fertile ground for mass bioinvasion of aquatic nuisance species which, in some cases, altered the original equilibrium of the entire basin. Finally, the Venice lagoon is presented as the third example of an environment subjected to high propagule pressure and anthropogenic forcing and bearing the higher "diversity" of non-indigenous species compared to the other Mediterranean lagoons. Stressed environments are easily colonised by alien species; understanding the links between human and natural disturbance and massive development of non-indigenous species will help prevent marine bioinvasions, that are already favoured by global oceanic trade.

  20. [Influence of Marine Aquaculture Around Coal Power Plant on Mercury Species Change in Auuatic Ecological Environment].

    PubMed

    Liang, Peng; Wang, Yuan-na; You, Qiong-zhi; Gao, Xue-fei; He, Shan-shan

    2015-08-01

    To investigate the influence of marine aquaculture around coal power plant on Hg species change in aquatic ecological environment, the fish farming area in Xiangshan Harbor, Zhejiang province, was studied. The concentrations of different Hg species in sea water collected from marine aquaculture sites (MS) and references sites (RS) were measured. The result showed that the total mercury (THg) concentration in the surface water reached 83.0 pmol x L(-1) +/- 97.1 pmol x L(-1). Dissolved Hg (DHg) in pore water of core sediment decreased with the increasing depth. Meanwhile, the DHg content in pore water above 10 cm was significantly higher (P < 0.001) than that below 10 cm, which confirmed the influence of coal-fired power plants on the surrounding areas. THg concentration in MS (96.5 pmol x L(-1) +/- 133 pmol x L(-1)) was higher than that in RS (69.5 pmol x L(-1) +/- 39.4 pmol x L(-1)), which was mainly resulted from the accumulation of sewage discharge by the employees and fish feed material in sediments during breeding that were further released to the overlying water. Methylmercury concentration in pore water of MS (24.0 pmol x L(-1) +/- 16.7 pmol x L(-1)) was also significantly higher than that in RS (6.60 pmol x L(-1) +/- 5.11 pmol x L(-1)), which demonstrated that marine aquaculture activities promoted the methylmercury production by increasing the accumulation of organic matter in sediment.

  1. Coralline alga reveals first marine record of subarctic North Pacific climate change

    USGS Publications Warehouse

    Halfar, J.; Steneck, R.; Schone, B.; Moore, G.W.K.; Joachimski, M.; Kronz, A.; Fietzke, J.; Estes, James

    2007-01-01

    While recent changes in subarctic North Pacific climate had dramatic effects on ecosystems and fishery yields, past climate dynamics and teleconnection patterns are poorly understood due to the absence of century-long high-resolution marine records. We present the first 117-year long annually resolved marine climate history from the western Bering Sea/Aleutian Island region using information contained in the calcitic skeleton of the long-lived crustose coralline red alga Clathromorphum nereostratum, a previously unused climate archive. The skeletal ??18O-time series indicates significant warming and/or freshening of surface waters after the middle of the 20th century. Furthermore, the time series is spatiotemporally correlated with Pacific Decadal Oscillation (PDO) and tropical El Nio??-Southern Oscillation (ENSO) indices. Even though the western Bering Sea/Aleutian Island region is believed to be outside the area of significant marine response to ENSO, we propose that an ENSO signal is transmitted via the Alaskan Stream from the Eastern North Pacific, a region of known ENSO teleconnections. Copyright 2007 by the American Geophysical Union.

  2. Coastal Marsh Sediments from Bodega Harbor: Archives of Environmental Changes at the Terrestrial-Marine Interface

    NASA Astrophysics Data System (ADS)

    Rademacher, L. K.; Rong, Y.; Hill, T. M.; Hiromoto, C.; Fisher, A.

    2010-12-01

    Coastal marsh sediments provide an important archive of environmental changes at the terrestrial-marine interface. Over the last century, humans have significantly altered the coastal environment near Bodega Bay, California, through changes in hydrology, sediment sources, and the dominant ecosystem. Previous investigations of recent coastal marsh sediments (< 50 years) suggest that physical barriers, such as roads, which limit the connection between Bodega Bay and the marshes, alters biogeochemical cycling (including carbon storage) in the coastal environment. The present study extends the record of changes in biogeochemical cycling in the coastal marshes back more than 100 years (approximately 90 cm) through the use of grain size analysis, C and N isotopes, and age dating. Sediments were analyzed for grain size distribution, the amount of carbon and nitrogen, and the stable isotopes of carbon and nitrogen in 1 cm intervals throughout the core. In addition, a subset of eight samples was analyzed for sediment age using a combination of Pb-210 and Cs-137 techniques. Sediments from >40 cm and <55 cm depth have a higher percentage of fine-grained sediment (>2%). In addition, these sediments also contain higher levels of total organic carbon and nitrogen, higher C:N ratios, we well as heavier carbon and nitrogen isotopic signatures. The sediments likely correspond to a pre-1900 depositional environment based on Pb-210 dates, when development in the region was increasing. These results suggest a stronger influence of the marine environment during that time. Interestingly, smaller transitions in sediment properties toward what appears to reflect a more marine environment also occur near the top of the core (<10 cm depth) and near the bottom of the core (>75 cm depth). Although these transitions are less pronounced, the significant shift in sediment properties suggests a less stable environment with greater communication between the terrestrial and marine environments

  3. Marine record of late quaternary glacial-interglacial fluctuations in the Ross Sea and evidence for rapid, episodic sea level change due to marine ice sheet collapse

    NASA Technical Reports Server (NTRS)

    Anderson, John B.

    1991-01-01

    Some of the questions to be addressed by SeaRISE include: (1) what was the configuration of the West Antarctic ice sheet during the last glacial maximum; (2) What is its configuration during a glacial minimum; and (3) has it, or any marine ice sheet, undergone episodic rapid mass wasting. These questions are addressed in terms of what is known about the history of the marine ice sheet, specifically in Ross Sea, and what further studies are required to resolve these problems. A second question concerns the extent to which disintegration of marine ice sheets may result in rises in sea level that are episodic in nature and extremely rapid, as suggested by several glaciologists. Evidence that rapid, episodic sea level changes have occurred during the Holocene is also reviewed.

  4. Measuring marine fish biodiversity: temporal changes in abundance, life history and demography

    PubMed Central

    Hutchings, Jeffrey A; Baum, Julia K

    2005-01-01

    Patterns in marine fish biodiversity can be assessed by quantifying temporal variation in rate of population change, abundance, life history and demography concomitant with long-term reductions in abundance. Based on data for 177 populations (62 species) from four north-temperate oceanic regions (Northeast Atlantic and Pacific, Northwest Atlantic, North mid-Atlantic), 81% of the populations in decline prior to 1992 experienced reductions in their rate of loss thereafter; species whose rate of population decline accelerated after 1992 were predominantly top predators such as Atlantic cod (Gadus morhua), sole (Solea solea) and pelagic sharks. Combining population data across regions and species, marine fish have declined 35% since 1978 and are currently less than 70% of recorded maxima; demersal species are generally at historic lows, pelagic species are generally stable or increasing in abundance. Declines by demersal species have been associated with substantive increases in pelagic species, a pattern consistent with the hypothesis that increases in the latter may be attributable to reduced predation mortality. There is a need to determine the consequences to population growth effected by the reductions in age (21%) and size (13%) at maturity and in mean age (5%) and size (18%) of spawners, concomitant with population decline. We conclude that reductions in the rate of population decline, in the absence of targets for population increase, will be insufficient to effect a recovery of marine fish biodiversity, and that great care must be exercised when interpreting multi-species patterns in abundance. Of fundamental importance is the need to explain the geographical, species-specific and habitat biases that pervade patterns of marine fish recovery and biodiversity. PMID:15814348

  5. Transforming the Rockies: Human forces, settlement patterns, and ecosystem effects

    USGS Publications Warehouse

    Travis, William R.; Theobald, David M.; Fagre, Daniel B.

    2002-01-01

    The current ecological condition of the Rocky Mountains can be viewed from two somewhat opposing perspectives. The first is that human occupation has had relatively little effect on the Rockies: large natural, if not pristine, areas remain, and the region's open spaces provide wildlife habitat, majestic scenery, and a sense of wildness. Unlike the situation in, say, the Swiss Alps, where even high-elevation meadows have been mown and grazed intensively for as long as 500 years and many large mammals have been extirpated, most elements of Rocky Mountain landscapes and biota are reasonably unaltered. Even the presumption that Native Americans changed regional landscapes with deliberately set fires has been challenged by Baker and Ehle (2001) and others who think that most fires were lightning-caused or accidental ignitions. The second view is that humans have dramatically transformed the Rockies, at least since Euro-American settlement in the mid- to late 1800s. The slaughter of vast buffalo herds, the clearing of timber for railroad ties, and even the removal of whole hillsides in hydraulic placer mining represented substantial transformation. Ranch, resort, and residential development marks the latest incarnation of this transformation. Numerous, complex layers of land use have left landscape legacies, some of which may be unrecognized or underappreciated in modern assessments (Wohl 2001). Here we consider both perspectives because we are impressed with both the many effects of human use of the Rockies and the region's remaining wild landscapes. Ironically, much of the recent population growth and development in the Rockies is driven by the region's wild landscapes, which make the present widespread transformation seem all the more significant. It is, of course, the rapid clip of current human transformation—high population growth rates, pervasive rural residential development, and landscape fragmentation (Baron, Theobald, and Fagre 2000)—that worries

  6. Synchronizing terrestrial and marine records of environmental change across the Eocene-Oligocene transition

    NASA Astrophysics Data System (ADS)

    Sahy, Diana; Condon, Daniel J.; Terry, Dennis O.; Fischer, Anne U.; Kuiper, Klaudia F.

    2015-10-01

    Records of terrestrial environmental change indicate that continental cooling and/or aridification may have predated the greenhouse-icehouse climate shift at the Eocene-Oligocene transition (EOT) by ca. 600 kyr. In North America, marine-terrestrial environmental change asynchronicity is inferred from a direct comparison between the astronomically tuned marine EOT record and published 40Ar/39Ar geochronology of volcanic tuffs from the White River Group (WRG) sampled at Flagstaff Rim (Wyoming) and Toadstool Geologic Park (Nebraska), which are type sections for the Chadronian and Orellan North American Land Mammal Ages. We present a new age-model for the WRG, underpinned by high-precision 206Pb/238U zircon dates from 15 volcanic tuffs, including six tuffs previously dated using the 40Ar/39Ar technique. Weighted mean zircon 206Pb/238U dates from this study are up to 1.0 Myr younger than published anorthoclase and biotite 40Ar/39Ar data (calibrated relative to Fish Canyon sanidine at 28.201 Ma). Giving consideration to the complexities, strengths, and limitations associated with both the 40Ar/39Ar and 206Pb/238U datasets, our interpretation is that the recalculated 40Ar/39Ar dates are anomalously old, and the 206Pb/238U (zircon) dates more accurately constrain deposition. 206Pb/238U calibrated age-depth models were developed in order to facilitate a robust intercomparison between marine and terrestrial archives of environmental change, and indicate that: (i) early Orellan (terrestrial) cooling recorded at Toadstool Geologic Park was synchronous with the onset of early Oligocene Antarctic glaciation and (ii) the last appearance datums of key Chadronian mammal taxa are diachronous by ca. 0.7 Myr between central Wyoming and NW Nebraska.

  7. Species sensitivity distributions for suspended clays, sediment burial, and grain size change in the marine environment.

    PubMed

    Smit, Mathijs G D; Holthaus, Karlijn I E; Trannum, Hilde C; Neff, Jerry M; Kjeilen-Eilertsen, Grete; Jak, Robbert G; Singsaas, Ivar; Huijbregts, Mark A J; Hendriks, A Jan

    2008-04-01

    Assessment of the environmental risk of discharges, containing both chemicals and suspended solids (e.g., drilling discharges to the marine environment), requires an evaluation of the effects of both toxic and nontoxic pollutants. To date, a structured evaluation scheme that can be used for prognostic risk assessments for nontoxic stress is lacking. In the present study we challenge this lack of information by the development of marine species sensitivity distributions (SSDs) for three nontoxic stressors: suspended clays, burial by sediment, and change in sediment grain size. Through a literature study, effect levels were obtained for suspended clays, as well as for burial of biota. Information on the species preference range for median grain size was used to assess the sensitivity of marine species to changes in grain size. The 50% hazardous concentrations (HC50) for suspended barite and bentonite based on 50% effect concentrations (EC50s) were 3,010 and 1,830 mg/L, respectively. For burial the 50% hazardous level (HL50) was 5.4 cm. For change in median grain size, two SSDs were constructed; one for reducing and one for increasing the median grain size. The HL50 for reducing the median grain size was 17.8 mum. For increasing the median grain size this value was 305 mum. The SSDs have been constructed by using information related to offshore oil- and gas-related activities. Nevertheless, the results of the present study may have broader implications. The hypothesis of the present study is that the SSD methodology developed for the evaluation of toxic stress can also be applied to evaluate nontoxic stressors, facilitating the incorporation of nontoxic stressors in prognostic risk assessment tools.

  8. Comparative phylogeography of two marine species of crustacean: Recent divergence and expansion due to environmental changes.

    PubMed

    Zhang, Daizhen; Ding, Ge; Ge, Baoming; Zhang, Huabin; Tang, Boping; Yang, Guang

    2014-10-15

    Environmental changes, such as changes in the coastal topography due to Eurasian plate movements, climate oscillation during the Pleistocene, and alteration of ocean currents, have complicated the geographical structure of marine species and deepened their divergence between populations. As two widely distributed species of crustacean (Oratosquilla oratoria and Eriocheir japonica), weak differences were expected due to their high dispersal potential of planktonic larvae with ocean currents. However, results showed a significant genetic divergence between north of China and south of China in the study. In addition, the estimated north-south divergence time (27-30.5 Myr) of mantis shrimp was near the time of the Himalayan movement, and the China-Japan clade divergence time (10.5-11.9 Myr) of mitten crabs was also coincident with the time of the opening of the Sea of Japan. Thus, we hypothesized that environmental changes in the coastal topography contributed to the marine species divergence. Furthermore, based on phylogenetic analysis, network analysis and haplotype distribution, we surmised that mitten crabs originated from a population with the oldest haplotype (H6) and then divided into the north and south populations due to the recent Eurasian plate movements and ocean currents. And lineage of Japan originated from the north population for the opening of the Sea of Japan. While O. oratoria was guessed to originate from two separate populations in the China Sea. The results of "star-like" network, negative values in neutral test, and Tajima's D statistics of two marine species supported a recent rapid population expansion event after the Pleistocene glaciations.

  9. Predicting multi-scale relationships between geomorphology and bedrock geology of the rocky intertidal in Central and Northern California

    NASA Astrophysics Data System (ADS)

    Wheeler, A.; Aiello, I. W.

    2014-12-01

    Substratum geology is fundamental in shaping rocky shore morphology. Specific lithologies have various responses to wave action, tectonic features (e.g. fractures, faults) and sedimentary structures (e.g. bedding), creating distinctive weathering profiles. Along with local oceanography and climate forcing, different rock substrata create coastal morphologies that can vary distinctly between scales, ranging from mm to km. Despite the complexity of the system, qualitative observations show coastal areas with similar rock types share similar geomorphologies. Thus, a statistic relationship between geomorphology (expressed for instance by surface parameter rugosity) and geology can be envisaged. There are multiple benefits of finding such a relationship, as rocky intertidal geomorphology can be an important determinant in which organisms can settle, grow, and survive in near shore communities: allowing the prediction of geomorphologic parameters determining coastal ecology solely based on substratum geology, a crucial aspect in guiding the selection of marine protected areas. This study presents preliminary results of multi-scale geospatial surveys (cm to tens of meters) of rocky intertidal outcrops from Central to Northern California using a Terrestrial Laser Scanner. The outcrops investigated are representative of the most common igneous and sedimentary rocks in California (granitoids, conglomerates, sandstones, mudstones) and metamorphic units. The statistical analysis of the survey data support the hypothesis that surface properties can change significantly with changing scale, each rock type having distinct surface characteristics which are similar to comparable lithologies exposed at different locations. These scale dependent variations are controlled by different lithologic and structural characteristics of the outcrop in question. Our data also suggests lithologic variability within a rock unit could be a very significant factor in controlling changes in

  10. Climate change in the marine Arctic in the early 21st century

    NASA Astrophysics Data System (ADS)

    Alekseev, Genrikh; Pnyushkov, Andrey; Ivanov, Nikolai; Balakin, Andrey

    2010-05-01

    The enhanced warming in the Arctic began in the middle of 1990s and maximized in 2007. During this period an abrupt shrinking of the summer ice extent occurred and significant positive anomaly of temperature in Atlantic Water (AW) layer in the Arctic Basin expanded over larger area. This climate shift coincided with the resumption of intensive field studies in the Arctic Ocean. The observations collected during the last two decades and especially in the frame of IPY 2007/08 international projects provided an enormous database of oceanographic, sea ice and atmospheric data that makes it possible to determine the climate shift in the marine Arctic, to compare the recent anomalies to those in 1970s and to link the Arctic climate shift to the global climate change. Observations show that since 1990 the surface air temperature (SAT) in the marine Arctic increased rapidly. The CMIP3 ensemble of climate models is seemed to underestimate the rise of SAT especially in summer. Time series of the AW layer parameters along with its pathway over the Arctic Basin during the period of 1930-2009 were compiled in order to trace the development of anomalies. Mean decadal oceanographic fields for 1990s and 2000s and for 2007 year were produced and its anomalies from 1970s were estimated. Rapid climate changes in the marine Arctic in 1990-2000s can not be accounted solely for the anthropogenic effect since the actually observed changes exceed the predictions of the global climate models. Our analysis emphasizes an important role of the increasing summer heat fluxes, as well as the influence of low latitude ocean variability and the solar activity. Other conclusion is that abrupt warming in the marine Arctic stopped in 2008-2009 and it is necessary to continue the monitoring of further changes. The studies were fulfilled in the frame of the AARI IPY projects, Applied Science Program of the Roshydromet and with support of the Russian Foundation for Basic Research (projects 06-05-64054a

  11. Trophic transfer of contaminants in a changing arctic marine food web: Cumberland Sound, Nunavut, Canada.

    PubMed

    McKinney, Melissa A; McMeans, Bailey C; Tomy, Gregg T; Rosenberg, Bruno; Ferguson, Steven H; Morris, Adam; Muir, Derek C G; Fisk, Aaron T

    2012-09-18

    Contaminant dynamics in arctic marine food webs may be impacted by current climate-induced food web changes including increases in transient/subarctic species. We quantified food web organochlorine transfer in the Cumberland Sound (Nunavut, Canada) arctic marine food web in the presence of transient species using species-specific biomagnification factors (BMFs), trophic magnification factors (TMFs), and a multifactor model that included δ(15)N-derived trophic position and species habitat range (transient versus resident), and also considered δ(13)C-derived carbon source, thermoregulatory group, and season. Transient/subarctic species relative to residents had higher prey-to-predator BMFs of biomagnifying contaminants (1.4 to 62 for harp seal, Greenland shark, and narwhal versus 1.1 to 20 for ringed seal, arctic skate, and beluga whale, respectively). For contaminants that biomagnified in a transient-and-resident food web and a resident-only food web scenario, TMFs were higher in the former (2.3 to 10.1) versus the latter (1.7 to 4.0). Transient/subarctic species have higher tissue contaminant levels and greater BMFs likely due to higher energetic requirements associated with long-distance movements or consumption of more contaminated prey in regions outside of Cumberland Sound. These results demonstrate that, in addition to climate change-related long-range transport/deposition/revolatilization changes, increasing numbers of transient/subarctic animals may alter food web contaminant dynamics.

  12. Managing Rocky Mountain spotted fever.

    PubMed

    Minniear, Timothy D; Buckingham, Steven C

    2009-11-01

    Rocky Mountain spotted fever is caused by the tick-borne bacterium Rickettsia rickettsii. Symptoms range from moderate illness to severe illness, including cardiovascular compromise, coma and death. The disease is prevalent in most of the USA, especially during warmer months. The trademark presentation is fever and rash with a history of tick bite, although tick exposure is unappreciated in over a third of cases. Other signature symptoms include headache and abdominal pain. The antibiotic therapy of choice for R. rickettsii infection is doxycycline. Preventive measures for Rocky Mountain spotted fever and other tick-borne diseases include: wearing long-sleeved, light colored clothing; checking for tick attachment and removing attached ticks promptly; applying topical insect repellent; and treating clothing with permethrin.

  13. Climate change and ocean acidification effects on seagrasses and marine macroalgae.

    PubMed

    Koch, Marguerite; Bowes, George; Ross, Cliff; Zhang, Xing-Hai

    2013-01-01

    Although seagrasses and marine macroalgae (macro-autotrophs) play critical ecological roles in reef, lagoon, coastal and open-water ecosystems, their response to ocean acidification (OA) and climate change is not well understood. In this review, we examine marine macro-autotroph biochemistry and physiology relevant to their response to elevated dissolved inorganic carbon [DIC], carbon dioxide [CO2 ], and lower carbonate [CO3 (2-) ] and pH. We also explore the effects of increasing temperature under climate change and the interactions of elevated temperature and [CO2 ]. Finally, recommendations are made for future research based on this synthesis. A literature review of >100 species revealed that marine macro-autotroph photosynthesis is overwhelmingly C3 (≥ 85%) with most species capable of utilizing HCO3 (-) ; however, most are not saturated at current ocean [DIC]. These results, and the presence of CO2 -only users, lead us to conclude that photosynthetic and growth rates of marine macro-autotrophs are likely to increase under elevated [CO2 ] similar to terrestrial C3 species. In the tropics, many species live close to their thermal limits and will have to up-regulate stress-response systems to tolerate sublethal temperature exposures with climate change, whereas elevated [CO2 ] effects on thermal acclimation are unknown. Fundamental linkages between elevated [CO2 ] and temperature on photorespiration, enzyme systems, carbohydrate production, and calcification dictate the need to consider these two parameters simultaneously. Relevant to calcifiers, elevated [CO2 ] lowers net calcification and this effect is amplified by high temperature. Although the mechanisms are not clear, OA likely disrupts diffusion and transport systems of H(+) and DIC. These fluxes control micro-environments that promote calcification over dissolution and may be more important than CaCO3 mineralogy in predicting macroalgal responses to OA. Calcareous macroalgae are highly vulnerable to OA

  14. 4. FIRSTFLOOR SHOWER/LOCKER ROOM. VIEW TO NORTHEAST. Rocky Mountain ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. FIRST-FLOOR SHOWER/LOCKER ROOM. VIEW TO NORTHEAST. - Rocky Mountain Arsenal, Administration-Laboratory- Change House-Bomb Rail, 420 feet South of December Seventh Avenue; 530 feet West of D Street, Commerce City, Adams County, CO

  15. 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.

  16. Seasonal and long-term changes in elemental concentrations and ratios of marine particulate organic matter

    NASA Astrophysics Data System (ADS)

    Talarmin, Agathe; Lomas, Michael W.; Bozec, Yann; Savoye, Nicolas; Frigstad, Helene; Karl, David M.; Martiny, Adam C.

    2016-11-01

    What is the temporal variability of the elemental stoichiometry of marine microbial communities across ocean regions? To answer this question, we present an analysis of environmental conditions, particulate organic carbon, nitrogen, and phosphorus concentrations and their ratios across 20 time series (3-25 years duration) representing estuarine, coastal, and open ocean environments. The majority of stations showed significant seasonal oscillations in particulate organic elemental concentrations and ratios. However, shorter-term changes contributed most to overall variance in particulate organic matter concentrations and ratios. We found a correlation between the seasonal oscillations of environmental conditions and elemental ratios at many coastal but not open ocean and estuarine stations. C:N peaked near the seasonal temperature minimum and nutrient maximum, but some stations showed other seasonal links. C:N ratios declined with time over the respective observation periods at all open ocean and estuarine stations as well as at five coastal station but increased at the nine other coastal stations. C:P (but not N:P) declined slightly at Bermuda Atlantic Time-series Study but showed large significant increases at Hawaii Ocean Time-series and Arendal stations. The relationships between long-term changes in environmental conditions and particulate organic matter concentrations or ratios were ambiguous, but interactions between changes in temperature and nutrient availability were important. Overall, our analysis demonstrates significant changes in elemental ratios at long-term and seasonal time scales across regions, but the underlying mechanisms are currently unclear. Thus, we need to better understand the detailed mechanisms driving the elemental composition of marine microbial ecosystems in order to predict how oceans will respond to environmental changes.

  17. Quantifying Preferences and Responsiveness of Marine Zooplankton to Changing Environmental Conditions using Microfluidics.

    PubMed

    Ramanathan, Nirupama; Simakov, Oleg; Merten, Christoph A; Arendt, Detlev

    2015-01-01

    Global environmental change significantly affects marine species composition. However, analyzing the impact of these changes on marine zooplankton communities was so far mostly limited to assessing lethal doses through mortality assays and hence did not allow a direct assessment of the preferred conditions, or preferendum. Here, we use a microfluidic device to characterize individual behavior of actively swimming zooplankton, and to quantitatively determine their ecological preferendum. For the annelid zooplankton model Platynereis dumerilii we observe a broader pH preferendum than for the copepod Euterpina acutifrons, and reveal previously unrecognized sub-populations with different pH preferenda. For Platynereis, the minimum concentration difference required to elicit a response (responsiveness) is ~1 μM for H+ and ~13.7 mM for NaCl. Furthermore, using laser ablations we show that olfactomedin-expressing sensory cells mediate chemical responsiveness in the Platynereis foregut. Taken together, our microfluidic approach allows precise assessment and functional understanding of environmental perception on planktonic behaviour.

  18. Crop failure rates in a geoengineered climate: impact of climate change and marine cloud brightening

    NASA Astrophysics Data System (ADS)

    Parkes, B.; Challinor, A.; Nicklin, K.

    2015-08-01

    The impact of geoengineering on crops has to date been studied by examining mean yields. We present the first work focusing on the rate of crop failures under a geoengineered climate. We investigate the impact of a future climate and a potential geoengineering scheme on the number of crop failures in two regions, Northeastern China and West Africa. Climate change associated with a doubling of atmospheric carbon dioxide increases the number of crop failures in Northeastern China while reducing the number of crop failures in West Africa. In both regions marine cloud brightening is likely to reduce the number crop failures, although it is more effective at reducing mild crop failure than severe crop failure. We find that water stress, rather than heat stress, is the main cause of crop failure in current, future and geoengineered climates. This demonstrates the importance of irrigation and breeding for tolerance to water stress as adaptation methods in all futures. Analysis of global rainfall under marine cloud brightening has the potential to significantly reduce the impact of climate change on global wheat and groundnut production.

  19. Exposure to low pH induces molecular level changes in the marine worm, Platynereis dumerilii.

    PubMed

    Wäge, Janine; Lerebours, Adelaide; Hardege, Jörg D; Rotchell, Jeanette M

    2016-02-01

    Fossil fuel emissions and changes in net land use lead to an increase in atmospheric CO2 concentration and a subsequent decrease of ocean pH. Noticeable effects on organisms' calcification rate, shell structure and energy metabolism have been reported in the literature. To date, little is known about the molecular mechanisms altered under low pH exposure, especially in non-calcifying organisms. We used a suppression subtractive hybridisation (SSH) approach to characterise differentially expressed genes isolated from Platynereis dumerilii, a non-calcifying marine polychaeta species, kept at normal and low pH conditions. Several gene sequences have been identified as differentially regulated. These are involved in processes previously considered as indicators of environment change, such as energy metabolism (NADH dehydrogenase, 2-oxoglutarate dehydrogenase, cytochrome c oxidase and ATP synthase subunit F), while others are involved in cytoskeleton function (paramyosin and calponin) and immune defence (fucolectin-1 and paneth cell-specific alpha-defensin) processes. This is the first study of differential gene expression in a non-calcifying, marine polychaete exposed to low pH seawater conditions and suggests that mechanisms of impact may include additional pathways not previously identified as impacted by low pH in other species.

  20. Quantifying Preferences and Responsiveness of Marine Zooplankton to Changing Environmental Conditions using Microfluidics

    PubMed Central

    Merten, Christoph A.; Arendt, Detlev

    2015-01-01

    Global environmental change significantly affects marine species composition. However, analyzing the impact of these changes on marine zooplankton communities was so far mostly limited to assessing lethal doses through mortality assays and hence did not allow a direct assessment of the preferred conditions, or preferendum. Here, we use a microfluidic device to characterize individual behavior of actively swimming zooplankton, and to quantitatively determine their ecological preferendum. For the annelid zooplankton model Platynereis dumerilii we observe a broader pH preferendum than for the copepod Euterpina acutifrons, and reveal previously unrecognized sub-populations with different pH preferenda. For Platynereis, the minimum concentration difference required to elicit a response (responsiveness) is ~1 μM for H+ and ~13.7 mM for NaCl. Furthermore, using laser ablations we show that olfactomedin-expressing sensory cells mediate chemical responsiveness in the Platynereis foregut. Taken together, our microfluidic approach allows precise assessment and functional understanding of environmental perception on planktonic behaviour. PMID:26517120

  1. Nitrogen removal properties in a continuous marine anammox bacteria reactor under rapid and extensive salinity changes.

    PubMed

    Wei, Qiaoyan; Kawagoshi, Yasunori; Huang, Xiaowu; Hong, Nian; Van Duc, Luong; Yamashita, Yuki; Hama, Takehide

    2016-04-01

    Salinity tolerance is one of the most important factors for the application of bioreactors to high-salinity wastewater. Although marine anammox bacteria (MAB) might be expected to tolerate higher salinities than freshwater anammox bacteria, there is little information on the effects of salinity on MAB activity. This study aimed to reveal the nitrogen removal properties in a continuous MAB reactor under conditions of rapid and extensive salinity changes. The reactor demonstrated stable nitrogen removal performance with a removal efficiency of over 85% under salinity conditions ranging from 0 to 50 g/L NaCl. The reactor performance was also well maintained, even though the salinity was rapidly changed from 30 to 50 g/L and from 30 to 0 g/L. Other evidence suggested that the seawater medium used contained components essential for effective MAB performance. Bacterial community analysis using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) showed that planctomycete UKU-1, the dominant MAB species in the inoculum, was the main contributor to anammox activity under all conditions. The PCR-DGGE using a universal bacterial primer set showed different DNA band patterns between the reactor biomass sample collected under conditions of 75 g/L NaCl and all other conditions (0, 30, 50 and freshwater-medium). All DNA sequences determined were very similar to those of bacterial species from marine environments, anaerobic environments, or wastewater-treatment facilities.

  2. Seasonal Changes in the Marine Production Cycles in Response to Changes in Arctic Sea Ice and Upper Ocean Circulation

    NASA Astrophysics Data System (ADS)

    Spitz, Y. H.; Ashjian, C. J.; Campbell, R. G.; Steele, M.; Zhang, J.

    2011-12-01

    Significant seasonal changes in arctic sea ice have been observed in recent years, characterized by unprecedented summer melt-back. As summer sea ice extent shrinks to record low levels, the peripheral seas of the Arctic Ocean are exposed much earlier to atmospheric surface heat flux, resulting in longer and warmer summers with more oceanic heat absorption. The changing seasonality in the arctic ice/ocean system will alter the timing, magnitude, duration, and pattern of marine production cycles by disrupting key trophic linkages and feedbacks in planktonic food webs. We are using a coupled pan-arctic Biology/Ice/Ocean Modeling and Assimilation System (BIOMAS) to investigate the changes in the patterns of seasonality in the arctic physical and biological system. Focus on specific regions of the Arctic, such as the Chukchi Sea, the Beaufort Sea and the adjacent central Arctic, reveals that changes in the timing of the spring bloom, its duration and the response of the secondary producers vary regionally. The major changes are, however, characterized by an earlier phytoplankton bloom and a slight increase of the biomass. In addition, the largest response in the secondary producers is seen in the magnitude of the microzooplankton concentration as well as in the period (early summer to late fall) over which the microzooplankton is present.

  3. The tropicalization of temperate marine ecosystems: climate-mediated changes in herbivory and community phase shifts

    PubMed Central

    Vergés, Adriana; Steinberg, Peter D.; Hay, Mark E.; Poore, Alistair G. B.; Campbell, Alexandra H.; Ballesteros, Enric; Heck, Kenneth L.; Booth, David J.; Coleman, Melinda A.; Feary, David A.; Figueira, Will; Langlois, Tim; Marzinelli, Ezequiel M.; Mizerek, Toni; Mumby, Peter J.; Nakamura, Yohei; Roughan, Moninya; van Sebille, Erik; Gupta, Alex Sen; Smale, Dan A.; Tomas, Fiona; Wernberg, Thomas; Wilson, Shaun K.

    2014-01-01

    Climate-driven changes in biotic interactions can profoundly alter ecological communities, particularly when they impact foundation species. In marine systems, changes in herbivory and the consequent loss of dominant habitat forming species can result in dramatic community phase shifts, such as from coral to macroalgal dominance when tropical fish herbivory decreases, and from algal forests to ‘barrens’ when temperate urchin grazing increases. Here, we propose a novel phase-shift away from macroalgal dominance caused by tropical herbivores extending their range into temperate regions. We argue that this phase shift is facilitated by poleward-flowing boundary currents that are creating ocean warming hotspots around the globe, enabling the range expansion of tropical species and increasing their grazing rates in temperate areas. Overgrazing of temperate macroalgae by tropical herbivorous fishes has already occurred in Japan and the Mediterranean. Emerging evidence suggests similar phenomena are occurring in other temperate regions, with increasing occurrence of tropical fishes on temperate reefs. PMID:25009065

  4. The tropicalization of temperate marine ecosystems: climate-mediated changes in herbivory and community phase shifts.

    PubMed

    Vergés, Adriana; Steinberg, Peter D; Hay, Mark E; Poore, Alistair G B; Campbell, Alexandra H; Ballesteros, Enric; Heck, Kenneth L; Booth, David J; Coleman, Melinda A; Feary, David A; Figueira, Will; Langlois, Tim; Marzinelli, Ezequiel M; Mizerek, Toni; Mumby, Peter J; Nakamura, Yohei; Roughan, Moninya; van Sebille, Erik; Gupta, Alex Sen; Smale, Dan A; Tomas, Fiona; Wernberg, Thomas; Wilson, Shaun K

    2014-08-22

    Climate-driven changes in biotic interactions can profoundly alter ecological communities, particularly when they impact foundation species. In marine systems, changes in herbivory and the consequent loss of dominant habitat forming species can result in dramatic community phase shifts, such as from coral to macroalgal dominance when tropical fish herbivory decreases, and from algal forests to 'barrens' when temperate urchin grazing increases. Here, we propose a novel phase-shift away from macroalgal dominance caused by tropical herbivores extending their range into temperate regions. We argue that this phase shift is facilitated by poleward-flowing boundary currents that are creating ocean warming hotspots around the globe, enabling the range expansion of tropical species and increasing their grazing rates in temperate areas. Overgrazing of temperate macroalgae by tropical herbivorous fishes has already occurred in Japan and the Mediterranean. Emerging evidence suggests similar phenomena are occurring in other temperate regions, with increasing occurrence of tropical fishes on temperate reefs.

  5. Density-dependent changes in effective area occupied for sea-bottom-associated marine fishes.

    PubMed

    Thorson, James T; Rindorf, Anna; Gao, Jin; Hanselman, Dana H; Winker, Henning

    2016-10-12

    The spatial distribution of marine fishes can change for many reasons, including density-dependent distributional shifts. Previous studies show mixed support for either the proportional-density model (PDM; no relationship between abundance and area occupied, supported by ideal-free distribution theory) or the basin model (BM; positive abundance-area relationship, supported by density-dependent habitat selection theory). The BM implies that fishes move towards preferred habitat as the population declines. We estimate the average relationship using bottom trawl data for 92 fish species from six marine regions, to determine whether the BM or PDM provides a better description for sea-bottom-associated fishes. We fit a spatio-temporal model and estimate changes in effective area occupied and abundance, and combine results to estimate the average abundance-area relationship as well as variability among taxa and regions. The average relationship is weak but significant (0.6% increase in area for a 10% increase in abundance), whereas only a small proportion of species-region combinations show a negative relationship (i.e. shrinking area when abundance increases). Approximately one-third of combinations (34.6%) are predicted to increase in area more than 1% for every 10% increase in abundance. We therefore infer that population density generally changes faster than effective area occupied during abundance changes. Gadiformes have the strongest estimated relationship (average 1.0% area increase for every 10% abundance increase) followed by Pleuronectiformes and Scorpaeniformes, and the Eastern Bering Sea shows a strong relationship between abundance and area occupied relative to other regions. We conclude that the BM explains a small but important portion of spatial dynamics for sea-bottom-associated fishes, and that many individual populations merit cautious management during population declines, because a compressed range may increase the efficiency of harvest.

  6. Using biogeographic distributions and natural history to predict marine/estuarine species at risk to climate change

    EPA Science Inventory

    Effects of climate change on marine and estuarine species will vary with attributes of the species and the spatial patterns of environmental change at the habitat and global scales. To better predict which species are at greatest risk, we are developing a knowledge base of specie...

  7. 76 FR 30827 - Temporary Change of Dates for Recurring Marine Event in the Fifth Coast Guard District; Elizabeth...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-27

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Temporary Change of Dates for Recurring Marine Event in the Fifth Coast Guard District; Elizabeth River, Norfolk, VA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard will temporarily change the enforcement period of...

  8. 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.

  9. 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.

  10. 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

  11. Rocky Flats Cleanup Agreement implementation successes and challenges

    SciTech Connect

    Shelton, D.C.

    1997-02-01

    On July 19, 1996 the US Department of Energy (DOE), State of Colorado (CDPHE), and US Environmental Protection Agency (EPA) entered into an agreement called the Rocky Flats Cleanup Agreement (RFCA) for the cleanup and closure of the Rocky Flats Environmental Technology Site (RFETS or Rocky Flats). Major elements of the agreement include: an Integrated Site-Wide Baseline; up to twelve significant enforceable milestones per year; agreed upon soil and water action levels and standards for cleanup; open space as the likely foreseeable land use; the plutonium and TRU waste removed by 2015; streamlined regulatory process; agreement with the Defense Nuclear Facilities Safety Board (DNFSB) to coordinate activities; and a risk reduction focus. Successful implementation of RFCA requires a substantial effort by the parties to change their way of thinking about RFETS and meet the deliverables and commitments. Substantial progress toward Site closure through the implementation of RFCA has been accomplished in the short time since the signing, yet much remains to be done. Much can be learned from the Rocky Flats experience by other facilities in similar situations.

  12. The relationship between sex change and reproductive success in a protandric marine gastropod

    PubMed Central

    Brante, Antonio; Quiñones, Adriana; Silva, Francisco

    2016-01-01

    Protandric species switch sex during their lifetime. According to theory, the time (body size) at which sex change occurs is determined by the reproductive success of individuals affected by social interactions as well as by post-copulatory factors. Experimental evidence is biased to few social systems making the exploration of general patterns difficult. We used the protandric marine gastropod Crepidula coquimbensis that partakes in intrabrood sibling cannibalism to test the following hypotheses: 1. Male-male competition for access to females and sibling cannibalism determine male reproductive success; 2. Males with greater access to females and with higher reproductive success will have reduced growth rates and will delay sex change. Artificial aggregations with different social structures were constructed and male reproductive success was estimated by paternity analysis. The results supported our expectations showing that male competitive ability for access to the female, time spent by males in the copulatory position, and sibling cannibalism affect reproductive success and influence time to sex change, with less successful males hastening sex change. Also, males that spent more time in the copulatory position had reduced growth rates. Comparing these results with those reported for other sequential hermaphrodites provides evidence supporting general patterns of sex change in nature. PMID:27385040

  13. Pathogenic marine microbes influence the effects of climate change on a commercially important tropical bivalve

    PubMed Central

    Turner, Lucy M.; Alsterberg, Christian; Turner, Andrew D.; Girisha, S. K.; Rai, Ashwin; Havenhand, Jonathan N.; Venugopal, M. N.; Karunasagar, Indrani; Godhe, Anna

    2016-01-01

    There is growing evidence that climate change will increase the prevalence of toxic algae and harmful bacteria, which can accumulate in marine bivalves. However, we know little about any possible interactions between exposure to these microorganisms and the effects of climate change on bivalve health, or about how this may affect the bivalve toxin-pathogen load. In mesocosm experiments, mussels, Perna viridis, were subjected to simulated climate change (warming and/or hyposalinity) and exposed to harmful bacteria and/or toxin-producing dinoflagellates. We found significant interactions between climate change and these microbes on metabolic and/or immunobiological function and toxin-pathogen load in mussels. Surprisingly, however, these effects were virtually eliminated when mussels were exposed to both harmful microorganisms simultaneously. This study is the first to examine the effects of climate change on determining mussel toxin-pathogen load in an ecologically relevant, multi-trophic context. The results may have considerable implications for seafood safety. PMID:27576351

  14. A universal driver of macroevolutionary change in the size of marine phytoplankton over the Cenozoic.

    PubMed

    Finkel, Z V; Sebbo, J; Feist-Burkhardt, S; Irwin, A J; Katz, M E; Schofield, O M E; Young, J R; Falkowski, P G

    2007-12-18

    The size structure of phytoplankton assemblages strongly influences energy transfer through the food web and carbon cycling in the ocean. We determined the macroevolutionary trajectory in the median size of dinoflagellate cysts to compare with the macroevolutionary size change in other plankton groups. We found the median size of the dinoflagellate cysts generally decreases through the Cenozoic. Diatoms exhibit an extremely similar pattern in their median size over time, even though species diversity of the two groups has opposing trends, indicating that the macroevolutionary size change is an active response to selection pressure rather than a passive response to changes in diversity. The changes in the median size of dinoflagellate cysts are highly correlated with both deep ocean temperatures and the thermal gradient between the surface and deep waters, indicating the magnitude and frequency of nutrient availability may have acted as a selective factor in the macroevolution of cell size in the plankton. Our results suggest that climate, because it affects stratification in the ocean, is a universal abiotic driver that has been responsible for macroevolutionary changes in the size structure of marine planktonic communities over the past 65 million years of Earth's history.

  15. Mass extinction of the marine biota at the Ordovician-Silurian transition due to environmental changes

    NASA Astrophysics Data System (ADS)

    Barash, M. S.

    2014-11-01

    The terminal Ordovician was marked by one of five great mass extinction events of the Phanerozoic (445.6-443.0 Ma ago), when up to 86% of the marine species became extinct. The rapid onset of the continental glaciation on Gondwana determined by its position in the South Pole area; the cooling; the hydrodynamic changes through the entire water column in the World Ocean; and the corresponding sea level fall, which was responsible for the reduction of shelf areas and shallow-water basins, i.e., the main ecological niche of the Ordovician marine biota, were main prerequisites of the stress conditions. Similar to other mass extinction events, these processes were accompanied by volcanism, impact events, a corresponding reduction of the photosynthesis and bioproductivity, the destruction of food chains, and anoxia. The appearance and development of terrestrial plants and microphytoplankton, which consumed atmospheric carbon dioxide, thus, diminishing the greenhouse effect and promoting the transition of the climatic system to the glacial mode, played a unique role in that period.

  16. Combined effects of global climate change and regional ecosystem drivers on an exploited marine food web.

    PubMed

    Niiranen, Susa; Yletyinen, Johanna; Tomczak, Maciej T; Blenckner, Thorsten; Hjerne, Olle; Mackenzie, Brian R; Müller-Karulis, Bärbel; Neumann, Thomas; Meier, H E Markus

    2013-11-01

    Changes in climate, in combination with intensive exploitation of marine resources, have caused large-scale reorganizations in many of the world's marine ecosystems during the past decades. The Baltic Sea in Northern Europe is one of the systems most affected. In addition to being exposed to persistent eutrophication, intensive fishing, and one of the world's fastest rates of warming in the last two decades of the 20th century, accelerated climate change including atmospheric warming and changes in precipitation is projected for this region during the 21st century. Here, we used a new multimodel approach to project how the interaction of climate, nutrient loads, and cod fishing may affect the future of the open Central Baltic Sea food web. Regionally downscaled global climate scenarios were, in combination with three nutrient load scenarios, used to drive an ensemble of three regional biogeochemical models (BGMs). An Ecopath with Ecosim food web model was then forced with the BGM results from different nutrient-climate scenarios in combination with two different cod fishing scenarios. The results showed that regional management is likely to play a major role in determining the future of the Baltic Sea ecosystem. By the end of the 21st century, for example, the combination of intensive cod fishing and high nutrient loads projected a strongly eutrophicated and sprat-dominated ecosystem, whereas low cod fishing in combination with low nutrient loads resulted in a cod-dominated ecosystem with eutrophication levels close to present. Also, nonlinearities were observed in the sensitivity of different trophic groups to nutrient loads or fishing depending on the combination of the two. Finally, many climate variables and species biomasses were projected to levels unseen in the past. Hence, the risk for ecological surprises needs to be addressed, particularly when the results are discussed in the ecosystem-based management context.

  17. Marine environmental changes at the Brazilian equatorial margin related to Amazon River evolution during the Neogene

    NASA Astrophysics Data System (ADS)

    Lammertsma, Emmy; Troelstra, Simon; Sangiorgi, Francesca; Chemale, Farid, Jr.; do Carmo, Dermeval A.; D'Avila, Roberto; Soares, Emilson; Hoorn, Carina

    2014-05-01

    Today, the nutrient-rich Amazon River outflow causes massive algal blooms in the western equatorial Atlantic Ocean, forming a considerable carbon sink as well as a primary food source in the otherwise oligotrophic surface water. However, the history of this high-productivity system is largely unknown, although a strong relation to the evolution of the Amazon River can be expected. The Amazon submarine fan provides direct evidence for the development of a transcontinental river system, of which the base of the primarily Andean-sourced siliciclastic deposits is dated as late Miocene. Ditch cuttings from Amazon Fan exploration 'Well 2' were made available by Petrobras for microfossil and lithological research. 'Well 2' is located on the uppermost fan at a water depth of 750 meters. Organic-walled dinoflagellate cyst and foraminifer assemblages were studied to reconstruct Neogene marine environmental changes in relation to the Amazon River development. Planktonic foraminifera are present throughout the studied section and largely confirm the already available biostratigraphic age determination based on nannofossils. Benthic foraminifer assemblages indicate that the paleo-water depth has not substantially deviated from current conditions. The ecological affinities of most observed dinocyst taxa are well known, which allows us to reconstruct changes in paleo-productivity based on the assemblages. Mineral composition suggests that local river systems already drained into the Amazon basin before the onset of the transcontinental system, but environmental conditions remained oligotrophic at this time. Decreased abundances of both dinocysts and planktonic foraminifera during the Pleistocene are related to highest sedimentation rates (dilution effect). Overall, a complex interplay of orogenesis, climatic and sea level variations during the Neogene are responsible for the fluvially-induced changes in the marine environment at the Atlantic margin.

  18. 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

  19. The Changing Strength and Nature of Fire-Climate Relationships in the Northern Rocky Mountains, U.S.A., 1902-2008

    PubMed Central

    Higuera, Philip E.; Abatzoglou, John T.; Littell, Jeremy S.; Morgan, Penelope

    2015-01-01

    Time-varying fire-climate relationships may represent an important component of fire-regime variability, relevant for understanding the controls of fire and projecting fire activity under global-change scenarios. We used time-varying statistical models to evaluate if and how fire-climate relationships varied from 1902-2008, in one of the most flammable forested regions of the western U.S.A. Fire-danger and water-balance metrics yielded the best combination of calibration accuracy and predictive skill in modeling annual area burned. The strength of fire-climate relationships varied markedly at multi-decadal scales, with models explaining < 40% to 88% of the variation in annual area burned. The early 20th century (1902-1942) and the most recent two decades (1985-2008) exhibited strong fire-climate relationships, with weaker relationships for much of the mid 20th century (1943-1984), coincident with diminished burning, less fire-conducive climate, and the initiation of modern fire fighting. Area burned and the strength of fire-climate relationships increased sharply in the mid 1980s, associated with increased temperatures and longer potential fire seasons. Unlike decades with high burning in the early 20th century, models developed using fire-climate relationships from recent decades overpredicted area burned when applied to earlier periods. This amplified response of fire to climate is a signature of altered fire-climate-relationships, and it implicates non-climatic factors in this recent shift. Changes in fuel structure and availability following 40+ yr of unusually low fire activity, and possibly land use, may have resulted in increased fire vulnerability beyond expectations from climatic factors alone. Our results highlight the potential for non-climatic factors to alter fire-climate relationships, and the need to account for such dynamics, through adaptable statistical or processes-based models, for accurately predicting future fire activity. PMID:26114580

  20. The Changing Strength and Nature of Fire-Climate Relationships in the Northern Rocky Mountains, U.S.A., 1902-2008.

    PubMed

    Higuera, Philip E; Abatzoglou, John T; Littell, Jeremy S; Morgan, Penelope

    2015-01-01

    Time-varying fire-climate relationships may represent an important component of fire-regime variability, relevant for understanding the controls of fire and projecting fire activity under global-change scenarios. We used time-varying statistical models to evaluate if and how fire-climate relationships varied from 1902-2008, in one of the most flammable forested regions of the western U.S.A. Fire-danger and water-balance metrics yielded the best combination of calibration accuracy and predictive skill in modeling annual area burned. The strength of fire-climate relationships varied markedly at multi-decadal scales, with models explaining < 40% to 88% of the variation in annual area burned. The early 20th century (1902-1942) and the most recent two decades (1985-2008) exhibited strong fire-climate relationships, with weaker relationships for much of the mid 20th century (1943-1984), coincident with diminished burning, less fire-conducive climate, and the initiation of modern fire fighting. Area burned and the strength of fire-climate relationships increased sharply in the mid 1980s, associated with increased temperatures and longer potential fire seasons. Unlike decades with high burning in the early 20th century, models developed using fire-climate relationships from recent decades overpredicted area burned when applied to earlier periods. This amplified response of fire to climate is a signature of altered fire-climate-relationships, and it implicates non-climatic factors in this recent shift. Changes in fuel structure and availability following 40+ yr of unusually low fire activity, and possibly land use, may have resulted in increased fire vulnerability beyond expectations from climatic factors alone. Our results highlight the potential for non-climatic factors to alter fire-climate relationships, and the need to account for such dynamics, through adaptable statistical or processes-based models, for accurately predicting future fire activity.

  1. The changing strength and nature of fire-climate relationships in the northern Rocky Mountains, U.S.A., 1902-2008

    USGS Publications Warehouse

    Littell, Jeremy

    2015-01-01

    Time-varying fire-climate relationships may represent an important component of fire-regime variability, relevant for understanding the controls of fire and projecting fire activity under global-change scenarios. We used time-varying statistical models to evaluate if and how fire-climate relationships varied from 1902-2008, in one of the most flammable forested regions of the western U.S.A. Fire-danger and water-balance metrics yielded the best combination of calibration accuracy and predictive skill in modeling annual area burned. The strength of fire-climate relationships varied markedly at multi-decadal scales, with models explaining < 40% to 88% of the variation in annual area burned. The early 20th century (1902-1942) and the most recent two decades (1985-2008) exhibited strong fire-climate relationships, with weaker relationships for much of the mid 20th century (1943-1984), coincident with diminished burning, less fire-conducive climate, and the initiation of modern fire fighting. Area burned and the strength of fire-climate relationships increased sharply in the mid 1980s, associated with increased temperatures and longer potential fire seasons. Unlike decades with high burning in the early 20th century, models developed using fire-climate relationships from recent decades overpredicted area burned when applied to earlier periods. This amplified response of fire to climate is a signature of altered fire-climate-relationships, and it implicates non-climatic factors in this recent shift. Changes in fuel structure and availability following 40+ yr of unusually low fire activity, and possibly land use, may have resulted in increased fire vulnerability beyond expectations from climatic factors alone. Our results highlight the potential for non-climatic factors to alter fire-climate relationships, and the need to account for such dynamics, through adaptable statistical or processes-based models, for accurately predicting future fire activity.

  2. Changes in bacterial communities of the marine sponge Mycale laxissima on transfer into aquaculture.

    PubMed

    Mohamed, Naglaa M; Enticknap, Julie J; Lohr, Jayme E; McIntosh, Scott M; Hill, Russell T

    2008-02-01

    The changes in bacterial communities associated with the marine sponge Mycale laxissima on transfer to aquaculture were studied using culture-based and molecular techniques. M. laxissima was maintained alive in flowthrough and closed recirculating aquaculture systems for 2 years and 1 year, respectively. The bacterial communities associated with wild and aquacultured sponges, as well as the surrounding water, were assessed using 16S rRNA gene clone library analysis and denaturing gradient gel electrophoresis (DGGE). Bacterial richness and diversity were measured using DOTUR computer software, and clone libraries were compared using S-LIBSHUFF. DGGE analysis revealed that the diversity of the bacterial community of M. laxissima increased when sponges were maintained in aquaculture and that bacterial communities associated with wild and aquacultured M. laxissima were markedly different than those of the corresponding surrounding water. Clone libraries of bacterial 16S rRNA from sponges confirmed that the bacterial communities changed during aquaculture. These communities were significantly different than those of seawater and aquarium water. The diversity of bacterial communities associated with M. laxissima increased significantly in aquaculture. Our work shows that it is important to monitor changes in bacterial communities when examining the feasibility of growing sponges in aquaculture systems because these communities may change. This could have implications for the health of sponges or for the production of bioactive compounds by sponges in cases where these compounds are produced by symbiotic bacteria rather than by the sponges themselves.

  3. Mismatch between marine plankton range movements and the velocity of climate change

    PubMed Central

    Chivers, William J.; Walne, Anthony W.; Hays, Graeme C.

    2017-01-01

    The response of marine plankton to climate change is of critical importance to the oceanic food web and fish stocks. We use a 60-year ocean basin-wide data set comprising >148,000 samples to reveal huge differences in range changes associated with climate change across 35 plankton taxa. While the range of dinoflagellates and copepods tended to closely track the velocity of climate change (the rate of isotherm movement), the range of the diatoms moved much more slowly. Differences in range shifts were up to 900 km in a recent warming period, with average velocities of range movement between 7 km per decade northwards for taxa exhibiting niche plasticity and 99 km per decade for taxa exhibiting niche conservatism. The differing responses of taxa to global warming will cause spatial restructuring of the plankton ecosystem with likely consequences for grazing pressures on phytoplankton and hence for biogeochemical cycling, higher trophic levels and biodiversity. PMID:28186097

  4. Modeling changes in extreme snowfall events in the Central Rocky Mountains Region with the Fully-Coupled WRF-Hydro Modeling System

    NASA Astrophysics Data System (ADS)

    gochis, David; rasmussen, Roy; Yu, Wei; Ikeda, Kyoko

    2014-05-01

    Modeling of extreme weather events often require very finely resolved treatment of atmospheric circulation structures in order to produce and localize large magnitudes of moisture fluxes that result in extreme precipitation. This is particularly true for cool season orographic precipitation processes where the representation of landform can significantly influence vertical velocity profiles and cloud moisture entrainment rates. In this work we report on recent progress in high resolution regional climate modeling of the Colorado Headwaters region using an updated version of the Weather Research and Forecasting (WRF) model and a hydrological extension package called WRF-Hydro. Previous work has shown that the WRF-Hydro modeling system forced by high resolution WRF model output can produce credible depictions of winter orographic precipitation and resultant monthly and annual river flows. Here we present results from a detailed study of an extreme springtime snowfall event that occurred along the Colorado Front Range in March of 2003. First an analysis of the simulated streamflows resulting from the melt out of that event are presented followed by an analysis of projected streamflows from the event where the atmospheric forcing in the WRF model is perturbed using the Psuedo-Global-Warming (PGW) perturbation methodology. Results from the impact of warming on total precipitation, snow-rain partitioning and surface hydrological fluxes (evapotranspiration and runoff) will be discussed in the context of how potential changes in temperature impact the amount of precipitation, the phase of precipitation (rain vs. snow) and the timing and amplitude of streamflow responses. It is shown that under the assumptions of the PGW method, intense precipitation rates increase during the event and, more importantly, that more precipitation falls as rain versus snow which significantly amplifies the runoff response from one where runoff is produced gradually to where runoff is more

  5. The linkage between marine sediment records and changes in Holocene Saharan landscape: simulating the dust cycle

    NASA Astrophysics Data System (ADS)

    Egerer, Sabine; Claussen, Martin; Reick, Christian; Stanelle, Tanja

    2016-04-01

    Marine sediment records reveal an abrupt and strong increase in dust deposition in the North Atlantic at the end of the African Humid Period about 4.9 ka to 5.5 ka ago (deMenocal et al., 2000; McGee et al., 2013). The change in dust flux has been attributed to varying Saharan land surface cover. Alternatively, the enhanced dust accumulation is linked to enhanced surface winds and a consequent intensification of coastal upwelling. We present simulation results from a recent sensitivity study, where we demonstrate for the first time the direct link between dust accumulation in marine cores and changes in Saharan land surface during the Holocene. We have simulated timeslices of he mid-Holocene (6 ka BP) and pre-industrial (1850 AD) dust cycle as a function of Saharan land surface cover and atmosphere-ocean conditions using the coupled atmosphere-aerosol model ECHAM6.1-HAM2.1. We prescribe mid-Holocene vegetation cover based on a vegetation reconstruction from pollen data (Hoelzmann et al., 1998) and mid-Holocene lake surface area is determined using a water routing and storage model (Tegen et al., 2002). In agreement with data from marine sediment cores, our simulations show that mid-Holocene dust deposition fluxes in the North Atlantic were two to three times lower compared with pre-industrial fluxes. We identify Saharan land surface characteristics to be the main control on dust transport from North Africa to the North Atlantic. We conclude that the variation in dust accumulation in marine cores is likely related to a transition of the Saharan landscape during the Holocene and not due to changes in atmospheric or ocean conditions alone. Reference: deMenocal, P., Ortiz, J., Guilderson, T., Adkins, J., Sarnthein, M., Baker, L., and Yarusinsky, M.: Abrupt onset and termination of the African Humid Period:: rapid climate responses to gradual insolation forcing, Quaternary Science Reviews, 19, 347-361, 2000. Hoelzmann, P., Jolly, D., Harrison, S. P., Laarif, F

  6. Rapid Oligocene Exhumation of the Western Canadian Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Szameitat, A.; Parrish, R. R.; Stuart, F. M.; Carter, A.; Fishwick, S.

    2014-12-01

    As part of the North American Cordillera the Rocky Mountains of Canada impact the deflection of weather systems and the jet stream and form a distinct barrier to Pacific moisture reaching the continental interior. The extent to which this climatic pattern extended into the past is at present uncertain, so improving our understanding of the elevation history of the Rockies is critical to determining the controls on climate change within the Northern Hemisphere. We have undertaken a comprehensive apatite (U-Th-Sm)/He and fission track study of the southeastern Canadian Cordillera, i.e. the southern Canadian Rocky Mountains, in order to provide insight into the mid to late Cenozoic uplift and exhumation history of this region. Thermal history and exhumation models of widespread low elevation samples in combination with 6 vertical profiles covering elevations from 500 up to 3100 m a.s.l. show at least 1500 m of rapid exhumation west of the Rocky Mountain Trench (RMT) during the Oligocene (Figure 1). In contrast, the ranges east of the RMT low elevation samples provide Eocene ages throughout. The data show a very different history of recent uplift of the Canadian Rockies compared to what is currently known from published work, which mostly infer that the eastern Canadian Cordillera has not experienced significant uplift since the Eocene. We propose that the most likely cause of this rock uplift was upwelling of asthenosphere around the eastward subducting Farallon Plate. This also led to the eruption of the nearby mainly Miocene Chilcotin Group flood basalts and could have caused underplating of the thin lithosphere west of the RMT, adding to the buoyancy of the plate and lifting the range. Because the Trench marks the edge of the normal thickness craton which was underthrust beneath the Rocky Mountains during the initial upper Cretaceous orogeny, the eastern Rockies have a normal lithosperic thickness. This would impede recent uplift and provides an explanation for the

  7. Climate change impacts on U.S. coastal and marine ecosystems

    USGS Publications Warehouse

    Scavia, Donald; Field, John C.; Boesch, Donald F.; Buddemeier, Robert W.; Burkett, Virginia; Cayan, Daniel R.; Fogarty, Michael; Harwell, Mark A.; Howarth, Robert W.; Mason, Curt; Reed, Denise J.; Royer, Thomas C.; Sallenger, Asbury H.; Titus, James G.

    2002-01-01

    Increases in concentrations of greenhouse gases projected for the 21st century are expected to lead to increased mean global air and ocean temperatures. The National Assessment of Potential Consequences of Climate Variability and Change (NAST 2001) was based on a series of regional and sector assessments. This paper is a summary of the coastal and marine resources sector review of potential impacts on shorelines, estuaries, coastal wetlands, coral reefs, and ocean margin ecosystems. The assessment considered the impacts of several key drivers of climate change: sea level change; alterations in precipitation patterns and subsequent delivery of freshwater, nutrients, and sediment; increased ocean temperature; alterations in circulation patterns; changes in frequency and intensity of coastal storms; and increased levels of atmospheric CO2. Increasing rates of sea-level rise and intensity and frequency of coastal storms and hurricanes over the next decades will increase threats to shorelines, wetlands, and coastal development. Estuarine productivity will change in response to alteration in the timing and amount of freshwater, nutrients, and sediment delivery. Higher water temperatures and changes in freshwater delivery will alter estuarine stratification, residence time, and eutrophication. Increased ocean temperatures are expected to increase coral bleaching and higher CO2 levels may reduce coral calcification, making it more difficult for corals to recover from other disturbances, and inhibiting poleward shifts. Ocean warming is expected to cause poleward shifts in the ranges of many other organisms, including commercial species, and these shifts may have secondary effects on their predators and prey. Although these potential impacts of climate change and variability will vary from system to system, it is important to recognize that they will be superimposed upon, and in many cases intensify, other ecosystem stresses (pollution, harvesting, habitat destruction

  8. 27 CFR 9.43 - Rocky Knob.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ....S.G.S. maps. The maps are entitled: “Willis Quadrangle Virginia” 7.5 minute series and “Woolwine Quadrangle Virginia” 7.5 minute series. (c) Boundaries. The Rocky Knob viticultural area is located in Floyd... Route No. 726 at the southern boundary of the Rocky Knob Recreation Area. (5) Then follow the...

  9. 27 CFR 9.43 - Rocky Knob.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Rocky Knob. 9.43 Section 9.43 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ALCOHOL AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.43 Rocky Knob....

  10. 27 CFR 9.43 - Rocky Knob.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Rocky Knob. 9.43 Section 9.43 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS AMERICAN VITICULTURAL AREAS Approved American Viticultural Areas § 9.43 Rocky Knob....

  11. Rocky Mountain spotted fever in children.

    PubMed

    Woods, Charles R

    2013-04-01

    Rocky Mountain spotted fever is typically undifferentiated from many other infections in the first few days of illness. Treatment should not be delayed pending confirmation of infection when Rocky Mountain spotted fever is suspected. Doxycycline is the drug of choice even for infants and children less than 8 years old.

  12. Rocky Mountain Spotted Fever: Statistics and Epidemiology

    MedlinePlus

    ... Search The CDC Cancel Submit Search The CDC Rocky Mountain Spotted Fever (RMSF) Note: Javascript is disabled or is not ... message, please visit this page: About CDC.gov . Rocky Mountain Spotted Fever (RMSF) Symptoms, Diagnosis, and Treatment Statistics and Epidemiology ...

  13. Abrupt climate change and transient climates during the Paleogene: a marine perspective

    NASA Technical Reports Server (NTRS)

    Zachos, J. C.; Lohmann, K. C.; Walker, J. C.; Wise, S. W.

    1993-01-01

    Detailed investigations of high latitude sequences recently collected by the Ocean Drilling Program (ODP) indicate that periods of rapid climate change often culminated in brief transient climates, with more extreme conditions than subsequent long term climates. Two examples of such events have been identified in the Paleogene; the first in latest Paleocene time in the middle of a warming trend that began several million years earlier: the second in earliest Oligocene time near the end of a Middle Eocene to Late Oligocene global cooling trend. Superimposed on the earlier event was a sudden and extreme warming of both high latitude sea surface and deep ocean waters. Imbedded in the latter transition was an abrupt decline in high latitude temperatures and the brief appearance of a full size continental ice-sheet on Antarctica. In both cases the climate extremes were not stable, lasting for less than a few hundred thousand years, indicating a temporary or transient climate state. Geochemical and sedimentological evidence suggest that both Paleogene climate events were accompanied by reorganizations in ocean circulation, and major perturbations in marine productivity and the global carbon cycle. The Paleocene-Eocene thermal maximum was marked by reduced oceanic turnover and decreases in global delta 13C and in marine productivity, while the Early Oligocene glacial maximum was accompanied by intensification of deep ocean circulation and elevated delta 13C and productivity. It has been suggested that sudden changes in climate and/or ocean circulation might occur as a result of gradual forcing as certain physical thresholds are exceeded. We investigate the possibility that sudden reorganizations in ocean and/or atmosphere circulation during these abrupt transitions generated short-term positive feedbacks that briefly sustained these transient climatic states.

  14. Abrupt climate change and transient climates during the Paleogene: a marine perspective.

    PubMed

    Zachos, J C; Lohmann, K C; Walker, J C; Wise, S W

    1993-03-01

    Detailed investigations of high latitude sequences recently collected by the Ocean Drilling Program (ODP) indicate that periods of rapid climate change often culminated in brief transient climates, with more extreme conditions than subsequent long term climates. Two examples of such events have been identified in the Paleogene; the first in latest Paleocene time in the middle of a warming trend that began several million years earlier: the second in earliest Oligocene time near the end of a Middle Eocene to Late Oligocene global cooling trend. Superimposed on the earlier event was a sudden and extreme warming of both high latitude sea surface and deep ocean waters. Imbedded in the latter transition was an abrupt decline in high latitude temperatures and the brief appearance of a full size continental ice-sheet on Antarctica. In both cases the climate extremes were not stable, lasting for less than a few hundred thousand years, indicating a temporary or transient climate state. Geochemical and sedimentological evidence suggest that both Paleogene climate events were accompanied by reorganizations in ocean circulation, and major perturbations in marine productivity and the global carbon cycle. The Paleocene-Eocene thermal maximum was marked by reduced oceanic turnover and decreases in global delta 13C and in marine productivity, while the Early Oligocene glacial maximum was accompanied by intensification of deep ocean circulation and elevated delta 13C and productivity. It has been suggested that sudden changes in climate and/or ocean circulation might occur as a result of gradual forcing as certain physical thresholds are exceeded. We investigate the possibility that sudden reorganizations in ocean and/or atmosphere circulation during these abrupt transitions generated short-term positive feedbacks that briefly sustained these transient climatic states.

  15. Climate change in the mid-latitudes of North America during the marine isotope stage 11

    NASA Astrophysics Data System (ADS)

    Gao, Y.; Rowe, H. D.; Wang, X.; Burnham, T. G.

    2008-12-01

    Orbital configurations during the Marine Isotope Stage (MIS) 11 are similar to those of today's interglacial period. Study on the climate of MIS 11 may provide information on the type and magnitude of modern climate variability that could be expected under non-anthropogenic conditions. We have obtained a high-resolution calcite speleothem record from Morril's Cave (aka Worley's Cave), eastern Tennessee. The chronology was determined by U-Th dates and stable isotopic analyses were done with a sampling interval of 0.5 mm. The sample was apparently deposited under equilibrium conditions. We thus interpret its stable isotope records, spanning continuously from ~400 ka to ~342 ka, in terms of climate and environmental changes at this mid-latitude location. The carbon isotope profile shows a step-wise increase of δ13C, shifting from approximately -12‰ in the middle of MIS 11 to -8‰ near the end of MIS 11 and then to -4‰ in MIS 10. This step-wise increase may indicate a wetting to drying climate shift near the end of MIS 11. In response to the climate change, it also suggests that C3 plants probably dominated in eastern Tennessee during MIS 11, while a major transition from C3 plants to C4 plants occurred in this region when the interglacial period terminated. The oxygen isotopic value gradually increases through the record, with oscillations following the local summer insolation. The record is consistent with marine and ice core records, but also featured with prominent millennial-scale variations, which suggests climate instability during the climate transition period.

  16. Closing Rocky Flats by 2006

    SciTech Connect

    Tuor, N. R.; Schubert, A. L.

    2002-02-26

    Safely accelerating the closure of Rocky Flats to 2006 is a goal shared by many: the State of Colorado, the communities surrounding the site, the U.S. Congress, the Department of Energy, Kaiser-Hill and its team of subcontractors, the site's employees, and taxpayers across the country. On June 30, 2000, Kaiser-Hill (KH) submitted to the Department of Energy (DOE), KH's plan to achieve closure of Rocky Flats by December 15, 2006, for a remaining cost of $3.96 billion (February 1, 2000, to December 15, 2006). The Closure Project Baseline (CPB) is the detailed project plan for accomplishing this ambitious closure goal. This paper will provide a status report on the progress being made toward the closure goal. This paper will: provide a summary of the closure contract completion criteria; give the current cost and schedule variance of the project and the status of key activities; detail important accomplishments of the past year; and discuss the challenges ahead.

  17. Rockies

    Atmospheric Science Data Center

    2014-05-15

    ... orbit 7447) include portions of southern Wyoming, central Colorado, and western Nebraska. The top view is from the instrument's ... 422 kilometers x 213 kilometers. The South Platte River enters just to the right of center at the top of the images. It winds its ...

  18. Marine bacterial community structure resilience to changes in protist predation under phytoplankton bloom conditions.

    PubMed

    Baltar, Federico; Palovaara, Joakim; Unrein, Fernando; Catala, Philippe; Horňák, Karel; Šimek, Karel; Vaqué, Dolors; Massana, Ramon; Gasol, Josep M; Pinhassi, Jarone

    2016-03-01

    To test whether protist grazing selectively affects the composition of aquatic bacterial communities, we combined high-throughput sequencing to determine bacterial community composition with analyses of grazing rates, protist and bacterial abundances and bacterial cell sizes and physiological states in a mesocosm experiment in which nutrients were added to stimulate a phytoplankton bloom. A large variability was observed in the abundances of bacteria (from 0.7 to 2.4 × 10(6) cells per ml), heterotrophic nanoflagellates (from 0.063 to 2.7 × 10(4) cells per ml) and ciliates (from 100 to 3000 cells per l) during the experiment (∼3-, 45- and 30-fold, respectively), as well as in bulk grazing rates (from 1 to 13 × 10(6) bacteria per ml per day) and bacterial production (from 3 to 379 μg per C l per day) (1 and 2 orders of magnitude, respectively). However, these strong changes in predation pressure did not induce comparable responses in bacterial community composition, indicating that bacterial community structure was resilient to changes in protist predation pressure. Overall, our results indicate that peaks in protist predation (at least those associated with phytoplankton blooms) do not necessarily trigger substantial changes in the composition of coastal marine bacterioplankton communities.

  19. Marine phytoplankton CO2 records since the Miocene - magnitudes of change inplied by cellular process models

    NASA Astrophysics Data System (ADS)

    Stoll, H. M.; Mejia, L. M.; Abrevaya, L.; Hernandez-Sanchez, M. T.; Bolton, C. T.; Mendez-Vicente, A.

    2015-12-01

    CO2 proxy records from the Mio-Pliocene rely heavily on data from the carbon isotopic fractionation of marine phytoplankton during photosynthesis (ep). However, fractionation is also sensitive to cell size, growth rate, and the degree of active C concentration at the site of photosynthesis. The ACTI-CO cell model provides one venue for exploring the implications of these multiple factors for the CO2 value consistent with a given ep determination. Using our recent alkenone ep record from the last 14 Ma, we explore in ACTI-CO mechanisms for using constraints of coccolith size for cell geometry, and coccolith calcification and isotopic fractionation coccoliths to constrain changes in carbon acquisition and the consequences for CO2 estimates. In addition, we present a new ep reconstruction for the past 13 Ma from the Equatorial Pacific based on diatom-bound organic matter . The isolation of pennate diatoms assures a similar cell geometry for the entire period, so that unlike the alkenone record, ep is not sensitive to temporal changes in cell size. The similar trends in CO2 from the size-corrected alkenone ep record and the diatom record suggest that there is a common global CO2 trend, and that size correction of the alkenone record reliably accounts for cell geometry effects. We employ the ACTI-CO model to evaluate the potential influence of changes in active carbon uptake on the magnitude of CO2 decrease since the Miocene.

  20. Marine bacterial community structure resilience to changes in protist predation under phytoplankton bloom conditions

    PubMed Central

    Baltar, Federico; Palovaara, Joakim; Unrein, Fernando; Catala, Philippe; Horňák, Karel; Šimek, Karel; Vaqué, Dolors; Massana, Ramon; Gasol, Josep M; Pinhassi, Jarone

    2016-01-01

    To test whether protist grazing selectively affects the composition of aquatic bacterial communities, we combined high-throughput sequencing to determine bacterial community composition with analyses of grazing rates, protist and bacterial abundances and bacterial cell sizes and physiological states in a mesocosm experiment in which nutrients were added to stimulate a phytoplankton bloom. A large variability was observed in the abundances of bacteria (from 0.7 to 2.4 × 106 cells per ml), heterotrophic nanoflagellates (from 0.063 to 2.7 × 104 cells per ml) and ciliates (from 100 to 3000 cells per l) during the experiment (∼3-, 45- and 30-fold, respectively), as well as in bulk grazing rates (from 1 to 13 × 106 bacteria per ml per day) and bacterial production (from 3 to 379 μg per C l per day) (1 and 2 orders of magnitude, respectively). However, these strong changes in predation pressure did not induce comparable responses in bacterial community composition, indicating that bacterial community structure was resilient to changes in protist predation pressure. Overall, our results indicate that peaks in protist predation (at least those associated with phytoplankton blooms) do not necessarily trigger substantial changes in the composition of coastal marine bacterioplankton communities. PMID:26262814

  1. Impacts of climate change on marine top predators: Advances and future challenges

    NASA Astrophysics Data System (ADS)

    Hobday, Alistair J.; Arrizabalaga, Haritz; Evans, Karen; Nicol, Simon; Young, Jock W.; Weng, Kevin C.

    2015-03-01

    Oceanic top predators are the subject of studies by researchers under the international Climate Impacts on Oceanic Top Predators (CLIOTOP) program. A wide range of data sets have shown that environmental conditions, such as temperature and marine productivity, affect the distribution and biological processes of these species, and thus the activities of the humans that depend on them. In this special issue, 25 papers arising from the 2nd CLIOTOP symposium, held in Noumea, New Caledonia in February 2013 report the importance of realistic physical descriptions of oceanic processes for climate change projections, demonstrate a wide range of predator responses to historical climate variability, describe new analytical approaches for understanding the physiology, behaviour and trophodynamics, and project future distributions for a range of species. Several contributions discuss the implications for conservation and fisheries and show that resolving ecosystem management challenges and conflicts in the face of climate change is possible, but will require attention by decision-makers to issues that are broader than their traditional mandate. In the coming years, an increased focus on the development of management options to reduce the impacts of climate change on top predators and their dependent industries is needed.

  2. Grazing-induced changes in cell wall silicification in a marine diatom.

    PubMed

    Pondaven, Philippe; Gallinari, Morgane; Chollet, Sophie; Bucciarelli, Eva; Sarthou, Géraldine; Schultes, Sabine; Jean, Frédéric

    2007-01-01

    In aquatic environments, diatoms (Bacillariophyceae) constitute a central group of microalgae which contribute to about 40% of the oceanic primary production. Diatoms have an absolute requirement for silicon to build-up their silicified cell wall in the form of two shells (the frustule). To date, changes in diatom cell wall silicification have been only studied in response to changes in the growth environment, with consistent increase in diatom silica content when specific growth rates decrease under nutrient or light limitations. Here, we report the first evidence for grazing-induced changes in cell wall silicification in a marine diatom. Cells grown in preconditioned media that had contained both diatoms and herbivores are significantly more silicified than diatoms grown in media that have contained diatoms alone or starved herbivores. These observations suggest that grazing-induced increase in cell wall silicification can be viewed as an adaptive reaction in habitats with variable grazing pressure, and demonstrate that silicification in diatoms is not only a constitutive mechanical protection for the cell, but also a phenotypically plastic trait modulated by grazing. In turn, our results corroborate the idea that plant-herbivore interactions, beyond grazing sensu stricto, contribute to drive ecosystem structure and biogeochemical cycles in the ocean.

  3. Marine plankton phenology and life history in a changing climate: current research and future directions

    PubMed Central

    Ji, Rubao; Edwards, Martin; Mackas, David L.; Runge, Jeffrey A.; Thomas, Andrew C.

    2010-01-01

    Increasing availability and extent of biological ocean time series (from both in situ and satellite data) have helped reveal significant phenological variability of marine plankton. The extent to which the range of this variability is modified as a result of climate change is of obvious importance. Here we summarize recent research results on phenology of both phytoplankton and zooplankton. We suggest directions to better quantify and monitor future plankton phenology shifts, including (i) examining the main mode of expected future changes (ecological shifts in timing and spatial distribution to accommodate fixed environmental niches vs. evolutionary adaptation of timing controls to maintain fixed biogeography and seasonality), (ii) broader understanding of phenology at the species and community level (e.g. for zooplankton beyond Calanus and for phytoplankton beyond chlorophyll), (iii) improving and diversifying statistical metrics for indexing timing and trophic synchrony and (iv) improved consideration of spatio-temporal scales and the Lagrangian nature of plankton assemblages to separate time from space changes. PMID:20824042

  4. Modelling potential changes in marine biogeochemistry due to large-scale offshore wind farms

    NASA Astrophysics Data System (ADS)

    van der Molen, Johan; Rees, Jon; Limpenny, Sian

    2013-04-01

    Large-scale renewable energy generation by offshore wind farms may lead to changes in marine ecosystem processes through the following mechanism: 1) wind-energy extraction leads to a reduction in local surface wind speeds; 2) these lead to a reduction in the local wind wave height; 3) as a consequence there's a reduction in SPM resuspension and concentrations; 4) this results in an improvement in under-water light regime, which 5) may lead to increased primary production, which subsequently 6) cascades through the ecosystem. A three-dimensional coupled hydrodynamics-biogeochemistry model (GETM_ERSEM) was used to investigate this process for a hypothetical wind farm in the central North Sea, by running a reference scenario and a scenario with a 10% reduction (as was found in a case study of a small farm in Danish waters) in surface wind velocities in the area of the wind farm. The ERSEM model included both pelagic and benthic processes. The results showed that, within the farm area, the physical mechanisms were as expected, but with variations in the magnitude of the response depending on the ecosystem variable or exchange rate between two ecosystem variables (3-28%, depending on variable/rate). Benthic variables tended to be more sensitive to the changes than pelagic variables. Reduced, but noticeable changes also occurred for some variables in a region of up to two farm diameters surrounding the wind farm. An additional model run in which the 10% reduction in surface wind speed was applied only for wind speeds below the generally used threshold of 25 m/s for operational shut-down showed only minor differences from the run in which all wind speeds were reduced. These first results indicate that there is potential for measurable effects of large-scale offshore wind farms on the marine ecosystem, mainly within the farm but for some variables up to two farm diameters away. However, the wave and SPM parameterisations currently used in the model are crude and need to be

  5. Colonization in the photic zone and subsequent changes during sinking determine bacterial community composition in marine snow.

    PubMed

    Thiele, Stefan; Fuchs, Bernhard M; Amann, Rudolf; Iversen, Morten H

    2015-02-01

    Due to sampling difficulties, little is known about microbial communities associated with sinking marine snow in the twilight zone. A drifting sediment trap was equipped with a viscous cryogel and deployed to collect intact marine snow from depths of 100 and 400 m off Cape Blanc (Mauritania). Marine snow aggregates were fixed and washed in situ to prevent changes in microbial community composition and to enable subsequent analysis using catalyzed reporter deposition fluorescence in situ hybridization (CARD-FISH). The attached microbial communities collected at 100 m were similar to the free-living community at the depth of the fluorescence maximum (20 m) but different from those at other depths (150, 400, 550, and 700 m). Therefore, the attached microbial community seemed to be “inherited” from that at the fluorescence maximum. The attached microbial community structure at 400 m differed from that of the attached community at 100 m and from that of any free-living community at the tested depths, except that collected near the sediment at 700 m. The differences between the particle-associated communities at 400 m and 100 m appeared to be due to internal changes in the attached microbial community rather than de novo colonization, detachment, or grazing during the sinking of marine snow. The new sampling method presented here will facilitate future investigations into the mechanisms that shape the bacterial community within sinking marine snow, leading to better understanding of the mechanisms which regulate biogeochemical cycling of settling organic matter.

  6. Past, present, and future changes in marine biogeochemistry in the Arabian Sea

    NASA Astrophysics Data System (ADS)

    Six, Katharina; Segschneider, Joachim

    2014-05-01

    The work presented here aims at a better understanding of the Asian Monsoon system including the marine biogeochemistry in the Arabian Sea. Changes in the past as recorded in marine sediments, as simulated over the past 1000 years, and under forcing by anthropogenic CO2 emissions by numerical model simulations are investigated. The investigation is based on three columns: a sediment core taken in the Arabian Sea (core SO130-275KL taken off Pakistan), a pre-industrial model run from 850 - 1850 with the Max Planck Institute's Earth System Model (MPI-ESM) including the marine and terrestrial carbon cycle and forced by solar variations and volcanic eruptions, and a continuation of this simulation to 2005 under the historical anthropogenic CO2 forcing which allows a comparison with present day climatology. In a first step we compare model results for a set of biogeochemical tracers within the water column and the sediment mixed with observations in the Arabian Sea. We further analyse correlations between Monsoon forcing (represented by zonal wind speed at 850 hPA, short wave radiation, Indian summer precipitation) and biogeochemical parameters, with particular focus on denitrification rates and fluxes to the sediment. This analysis is focused on three regions: off Somalia and off Oman for the summer monsoon, and the central Arabian Sea for the winter monsoon. For the summer monsoon, the highest correlation is found between zonal wind speed and calcite flux to the sediment off Somalia, for the winter monsoon the correlation is highest for short wave radiation in the central Arabian Sea. Time series of mixed layer depth and integrated primary production within the upper 100 m of the ocean from a CMIP5 historical experiment (1850-2005) show, at the location of the sediment core SO130-275KL, little correlation during the summer monsoon, but good correlation during the winter monsoon. As a result, the sediment core is more likely to document winter monsoon conditions

  7. Change in the Beaufort Sea ecosystem: Diverging trends in body condition and/or production in five marine vertebrate species

    NASA Astrophysics Data System (ADS)

    Harwood, L. A.; Smith, T. G.; George, J. C.; Sandstrom, S. J.; Walkusz, W.; Divoky, G. J.

    2015-08-01

    Studies of the body condition of five marine vertebrate predators in the Beaufort Sea, conducted independently during the past 2-4 decades, suggest each has been affected by biophysical changes in the marine ecosystem. We summarize a temporal trend of increasing body condition in two species (bowhead whale subadults, Arctic char), in both cases influenced by the extent and persistence of annual sea ice. Three other species (ringed seal, beluga, black guillemot chicks), consumers with a dietary preference for Arctic cod, experienced declines in condition, growth and/or production during the same time period. The proximate causes of these observed changes remain unknown, but may reflect an upward trend in secondary productivity, and a concurrent downward trend in the availability of forage fishes, such as the preferred Arctic cod. To further our understanding of these apparent ecosystem shifts, we urge the use of multiple marine vertebrate species in the design of biophysical sampling studies to identify causes of these changes. Continued long-term, standardized monitoring of vertebrate body condition should be paired with concurrent direct (stomach contents) or indirect (isotopes, fatty acids) monitoring of diet, detailed study of movements and seasonal ranges to establish and refine baselines, and identification of critical habitats of the marine vertebrates being monitored. This would be coordinated with biophysical and oceanographic sampling, at spatial and temporal scales, and geographic locations, that are relevant to the home range, critical habitats and prey of the vertebrate indicator species showing changes in condition and related parameters.

  8. Southeast Atlantic marine and terrestrial response to middle Pliocene climate change

    USGS Publications Warehouse

    Dowsett, H.; Willard, D.

    1996-01-01

    Analysis of planktic foraminifers and pollen from Deep Sea Drilling Project Site 532 located on the continental margin of southwest Africa provides information on the link between Pliocene paleoceanographic conditions and paleoenvironments of southwest Africa. Increased upwelling at Site 532 correlates with southward migration of onshore vegetation regions. Both terrestrial and marine changes can be explained by changes in the southern hemisphere surface temperature gradient which affected the paleo-position of subtropical high pressure cells and productivity of water masses during the Pliocene. When the subtropical high pressure cells were further south, Southern Ocean waters were warmer, contained less sea ice, Southern Ocean diatom productivity was high, and nutrient depleted water upwelled off southwest Africa. When the subtropical high pressure cells were in a configuration similar to the present, Southern Ocean waters were cooler and contained more sea ice, the aerial extent of Southern Ocean diatom productivity was limited, and nutrient rich waters upwelled off southwest Africa as the Benguela upwelling system migrated closer to the position of Site 532.

  9. Fatal Rocky Mountain spotted fever.

    PubMed

    Hattwick, M A; Retailliau, H; O'Brien, R J; Slutzker, M; Fontaine, R E; Hanson, B

    1978-09-29

    Forty-four fatal cases of Rocky Mountain spotted fever (RMSF) occurring in 1974 were compared with 50 nonfatal cases of similar age, sex, date of onset, and place of occurrence. Diagnosis and initiation of treatment in fatal cases were substantially delayed compared with nonfatal cases. Several reasons for this delay were identified: (1) the rash appeared later in the course of illness in the fatal cases, often not until the patient was terminal, (2) a history of tick bite was less often obtained during life or obtained late in the clinical course in fatal cases, and (3) initial nonspecific symptoms or unexpected symptoms led to an initial diagnosis of more common diseases. Only two fatal cases were treated with either tetracycline or chloramphenicol before the sixth day of illness. Presumptive diagnosis of RMSF and initiation of tetracycline therapy before onset of rash may be necessary to reduce mortality.

  10. 15N/14N variations in Cretaceous Atlantic sedimentary sequences: implication for past changes in marine nitrogen biogeochemistry

    USGS Publications Warehouse

    Rau, G.H.; Arthur, M.A.; Dean, W.E.

    1987-01-01

    At two locations in the Atlantic Ocean (DSDP Sites 367 and 530) early to middle Cretaceous organic-carbon-rich beds ("black shales") were found to have significantly lower ??15N values (lower 15N/14N ratios) than adjacent organic-carbon-poor beds (white limestones or green claystones). While these lithologies are of marine origin, the black strata in particular have ??15N values that are significantly lower than those previously found in the marine sediment record and most contemporary marine nitrogen pools. In contrast, black, organic-carbon-rich beds at a third site (DSDP Site 603) contain predominantly terrestrial organic matter and have C- and N-isotopic compositions similar to organic matter of modern terrestrial origin. The recurring 15N depletion in the marine-derived Cretaceous sequences prove that the nitrogen they contain is the end result of an episodic and atypical biogeochemistry. Existing isotopic and other data indicate that the low 15N relative abundance is the consequence of pelagic rather than post-depositional processes. Reduced ocean circulation, increased denitrification, and, hence, reduced euphotic zone nitrate availability may have led to Cretaceous phytoplankton assemblages that were periodically dominated by N2-fixing blue-green algae, a possible source of this sediment 15N-depletion. Lack of parallel isotopic shifts in Cretaceous terrestrially-derived nitrogen (Site 603) argues that the above change in nitrogen cycling during this period did not extend beyond the marine environment. ?? 1987.

  11. 32. AERIAL VIEW OF THE ROCKY FLATS PLANT LOOKING NORTHWEST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    32. AERIAL VIEW OF THE ROCKY FLATS PLANT LOOKING NORTHWEST. DURING THE 1980S, A NUMBER OF COMPLAINTS CONCERNING SAFETY AND ENVIRONMENTAL ERRORS SURFACED, CULMINATING IN THE 1989 RAID ON THE PLANT BY THE FBI FOR ALLEGED ENVIRONMENTAL INFRACTIONS. THAT SAME YEAR, PRODUCTION AT THE PLANT WAS HALTED FOR CORRECTION OF SAFETY DEFICIENCIES. BY 1991, A SERIES OF EVENTS WORLDWIDE REDUCED THE COLD WAR THREAT, AND IN 1992, THE SECRETARY OF ENERGY ANNOUNCED THAT THE MISSION AT THE PLANT WOULD BE CHANGED TO ENVIRONMENTAL RESTORATION AND WASTE MANAGEMENT, WITH THE GOAL OF CLEANING UP THE PLANT AND SITE (1989). - Rocky Flats Plant, Bounded by Indiana Street & Routes 93, 128 & 72, Golden, Jefferson County, CO

  12. Map of mixed prairie grassland vegetation, Rocky Flats, Colorado

    SciTech Connect

    Clark, S J.V.; Webber, P J; Komarkova, V; Weber, W A

    1980-01-01

    A color vegetation map at the scale of 1:12,000 of the area surrounding the Rocky Flats, Rockwell International Plant near Boulder, Colorado, provides a permanent record of baseline data which can be used to monitor changes in both vegetation and environment and thus to contribute to future land management and land-use policies. Sixteen mapping units based on species composition were identified, and characterized by two 10-m/sup 2/ vegetation stands each. These were grouped into prairie, pasture, and valley side on the basis of their species composition. Both the mapping units and these major groups were later confirmed by agglomerative clustering analysis of the 32 vegetation stands on the basis of species composition. A modified Bray and Curtis ordination was used to determine the environmental factor complexes controlling the distribution of vegetation at Rocky flats. Recommendations are made for future policies of environmental management and predictions of the response to environmental change of the present vegetation at the Rocky Flats site.

  13. Marine species in ambient low-oxygen regions subject to double jeopardy impacts of climate change.

    PubMed

    Stortini, Christine H; Chabot, Denis; Shackell, Nancy L

    2016-10-18

    We have learned much about the impacts of warming on the productivity and distribution of marine organisms, but less about the impact of warming combined with other environmental stressors, including oxygen depletion. Also, the combined impact of multiple environmental stressors requires evaluation at the scales most relevant to resource managers. We use the Gulf of St. Lawrence, Canada, characterized by a large permanently hypoxic zone, as a case study. Species distribution models were used to predict the impact of multiple scenarios of warming and oxygen depletion on the local density of three commercially and ecologically important species. Substantial changes are projected within 20-40 years. A eurythermal depleted species already limited to shallow, oxygen-rich refuge habitat (Atlantic cod) may be relatively uninfluenced by oxygen depletion but increase in density within refuge areas with warming. A more stenothermal, deep-dwelling species (Greenland halibut) is projected to lose ~55% of its high-density areas under the combined impacts of warming and oxygen depletion. Another deep-dwelling, more eurythermal species (Northern shrimp) would lose ~4% of its high-density areas due to oxygen depletion alone, but these impacts may be buffered by warming, which may increase density by 8% in less hypoxic areas, but decrease density by ~20% in the warmest parts of the region. Due to local climate variability and extreme events, and that our models cannot project changes in species sensitivity to hypoxia with warming, our results should be considered conservative. We present an approach to effectively evaluate the individual and cumulative impacts of multiple environmental stressors on a species-by-species basis at the scales most relevant to managers. Our study may provide a basis for work in other low-oxygen regions and should contribute to a growing literature base in climate science, which will continue to be of support for resource managers as climate change

  14. Cascading Effects of Ocean Acidification in a Rocky Subtidal Community

    PubMed Central

    Asnaghi, Valentina; Chiantore, Mariachiara; Mangialajo, Luisa; Gazeau, Frédéric; Francour, Patrice; Alliouane, Samir; Gattuso, Jean-Pierre

    2013-01-01

    Temperate marine rocky habitats may be alternatively characterized by well vegetated macroalgal assemblages or barren grounds, as a consequence of direct and indirect human impacts (e.g. overfishing) and grazing pressure by herbivorous organisms. In future scenarios of ocean acidification, calcifying organisms are expected to be less competitive: among these two key elements of the rocky subtidal food web, coralline algae and sea urchins. In order to highlight how the effects of increased pCO2 on individual calcifying species will be exacerbated by interactions with other trophic levels, we performed an experiment simultaneously testing ocean acidification effects on primary producers (calcifying and non-calcifying algae) and their grazers (sea urchins). Artificial communities, composed by juveniles of the sea urchin Paracentrotus lividus and calcifying (Corallina elongata) and non-calcifying (Cystoseira amentacea var stricta, Dictyota dichotoma) macroalgae, were subjected to pCO2 levels of 390, 550, 750 and 1000 µatm in the laboratory. Our study highlighted a direct pCO2 effect on coralline algae and on sea urchin defense from predation (test robustness). There was no direct effect on the non-calcifying macroalgae. More interestingly, we highlighted diet-mediated effects on test robustness and on the Aristotle's lantern size. In a future scenario of ocean acidification a decrease of sea urchins' density is expected, due to lower defense from predation, as a direct consequence of pH decrease, and to a reduced availability of calcifying macroalgae, important component of urchins' diet. The effects of ocean acidification may therefore be contrasting on well vegetated macroalgal assemblages and barren grounds: in the absence of other human impacts, a decrease of biodiversity can be predicted in vegetated macroalgal assemblages, whereas a lower density of sea urchin could help the recovery of shallow subtidal rocky areas affected by overfishing from barren grounds to

  15. Cascading effects of ocean acidification in a rocky subtidal community.

    PubMed

    Asnaghi, Valentina; Chiantore, Mariachiara; Mangialajo, Luisa; Gazeau, Frédéric; Francour, Patrice; Alliouane, Samir; Gattuso, Jean-Pierre

    2013-01-01

    Temperate marine rocky habitats may be alternatively characterized by well vegetated macroalgal assemblages or barren grounds, as a consequence of direct and indirect human impacts (e.g. overfishing) and grazing pressure by herbivorous organisms. In future scenarios of ocean acidification, calcifying organisms are expected to be less competitive: among these two key elements of the rocky subtidal food web, coralline algae and sea urchins. In order to highlight how the effects of increased pCO2 on individual calcifying species will be exacerbated by interactions with other trophic levels, we performed an experiment simultaneously testing ocean acidification effects on primary producers (calcifying and non-calcifying algae) and their grazers (sea urchins). Artificial communities, composed by juveniles of the sea urchin Paracentrotus lividus and calcifying (Corallina elongata) and non-calcifying (Cystoseira amentacea var stricta, Dictyota dichotoma) macroalgae, were subjected to pCO2 levels of 390, 550, 750 and 1000 µatm in the laboratory. Our study highlighted a direct pCO2 effect on coralline algae and on sea urchin defense from predation (test robustness). There was no direct effect on the non-calcifying macroalgae. More interestingly, we highlighted diet-mediated effects on test robustness and on the Aristotle's lantern size. In a future scenario of ocean acidification a decrease of sea urchins' density is expected, due to lower defense from predation, as a direct consequence of pH decrease, and to a reduced availability of calcifying macroalgae, important component of urchins' diet. The effects of ocean acidification may therefore be contrasting on well vegetated macroalgal assemblages and barren grounds: in the absence of other human impacts, a decrease of biodiversity can be predicted in vegetated macroalgal assemblages, whereas a lower density of sea urchin could help the recovery of shallow subtidal rocky areas affected by overfishing from barren grounds to

  16. Paleoecological studies on variability in marine fish populations: A long-term perspective on the impacts of climatic change on marine ecosystems

    NASA Astrophysics Data System (ADS)

    Finney, Bruce P.; Alheit, Jürgen; Emeis, Kay-Christian; Field, David B.; Gutiérrez, Dimitri; Struck, Ulrich

    2010-02-01

    The use of historical fishing records to understand relationships between climatic change and fish abundance is limited by the relatively short duration of these records, and complications due to the strong influence of human activity in addition to climatic change. Sedimentary records containing scales, bones or geochemical proxies of variability in fish populations provide unique insights on long-term ecosystem dynamics and relationships with climatic change. Available records from Holocene sediments are summarized and synthesized. The records are from several widespread locations near or along the continental margins of the South Atlantic and Pacific oceans, including Alaska, USA (Pacific salmon), Saanich and Effingham Inlets, British Columbia, Canada (pelagic fish), Santa Barbara Basin, California, USA (Northern anchovies and Pacific sardines), Gulf of California, Mexico (Pacific sardines, Northern anchovies and Pacific hake), Peru upwelling system (sardines, anchovies and hake), and Benguela Current System, South Africa (sardines, anchovies and hake). These records demonstrate that fish population sizes are not constant, and varied significantly over a range of time scales prior to the advent of large-scale commercial fishing. In addition to the decadal-scale variability commonly observed in historical records, the long-term records reveal substantial variability over centennial and millennial time scales. Shifts in abundance are often, but not always, correlated with regional and/or global climatic changes. The long-term perspective reveals different patterns of variability in fish populations, as well as fish-climate relationships, than suggested by analysis of historical records. Many records suggest prominent changes in fish abundance at ca. 1000-1200 AD, during the Little Ice Age, and during the transition at the end of the Little Ice Age in the 19th century that may be correlative, and that were likely driven by major hemispheric or global

  17. Marine osmium isotopic record of cherts across the Triassic-Jurassic boundary: implications for environmental change

    NASA Astrophysics Data System (ADS)

    Suzuki, K.; Kuroda, J.; Hori, R. S.; Ohkouchi, N.; Grocke, D. R.

    2010-12-01

    Attention has long been focused on relationships between massive volcanisms and major environmental change such as large mass extinctions (e.g., Wignall, 2001). The Triassic-Jurassic (T-J) boundary at c.a. 200 Ma has been regarded as one of the five biggest mass extinction events in the Phanerozoic when a substantial proportion of marine and terrestrial species became extinct. This period also marks extensive magmatic activities associated with the emplacement of the Central Atlantic Magmatic Province (CAMP). These magmatic activities are likely to be a possible forcing mechanism for the climatic changes in the T-J transition. However, the mechanism triggering the T-J mass extinction is still under debate, because there are remarkable difficulties in correlating the timing of the widespread CAMP volcanic activity with the environmental events, and in estimating the environmental impact of large-scale igneous activity. Since seawater Os isotopic composition varies in response to change in balance of Os supply from continental, mantle and extraterrestrial sources, Os isotopic record from hydrogenous fraction of marine sediments is useful to reconstruct secular changes in the relative contribution from these sources (Ravizza and Peucker-Ehrenbrink, 2003; Tugeon and Creaser, 2008; Tejada et al., 2009). Such information possibly provides us important constraints on the mechanism of the environmental change and mass extinction. Although Cohen and Coe (2007) have reported Os isotopic records across the T-J boundary from southern England, no data have been reported from the Paleo-Pacific (Panthalassa) pelagic basin that covered approximately half of the Earth’s surface. Here we present a high-resolution isotopic record of osmium extracted from bedded chert successions across the T-J boundary in Kurusu section, central Japan, deposited on a Panthalassa deep basin. Our new dataset show a gradual decrease in seawater 187Os/188Os values through the Rhaetian and subsequent

  18. The effects of changing demographics on the distribution of marine anemia in farmed salmon in British Columbia.

    PubMed

    Stephen, R C; Ribble, C S

    1995-09-01

    The changing geographic distribution of marine anemia (plasmacytoid leukemia) was compared with the evolving demographics of the chinook farming industry in British Columbia to explore the hypothesis that the disease had spread throughout the province between 1987 and 1992. Through retrospective and prospective methods, it was shown that the apparent spread of the disease was likely an artifact, resulting from changes in the distribution of fish farms throughout the province and corresponding changes in the intensity of regional disease surveillance. When viewed over a 5-year period, there were no statistically significant differences in the prevalence of the disease amongst fish sampled from each of the major salmon farming regions of British Columbia. By increasing the intensity of surveillance for the disease in apparently negative regions or chinook farms, one could routinely find cases of the disease. The results suggest that marine anemia is an endemic problem for farmed chinook salmon in British Columbia and is not a spreading epidemic.

  19. Cadmium-induced changes in trace element bioaccumulation and proteomics perspective in four marine bivalves.

    PubMed

    Liu, Fengjie; Wang, Da-Zhi; Wang, Wen-Xiong

    2012-06-01

    Bivalves are employed widely as biomonitors of metal pollution and proteomics has increasingly been applied to solve ecotoxicological issues. This study aimed to investigate the effects of Cd exposure on the bioaccumulation of other trace elements and reveal the molecular mechanisms using proteomics technologies. The results showed that Cd exposure resulted in remarkable changes in body concentrations of Zn, Cu, Ag, Co, Ni, Pb, and Se in four marine bivalves (scallop Chlamys nobilis, clam Ruditapes philippinarum, mussel Perna viridis, and oyster Saccostrea cucullata). Generally, the bivalves exposed to higher Cd concentration accumulated higher concentrations of Zn, Cu, and Se, but a lower concentration of Co. The accumulation of Ag, Ni, and Pb was specific for different species. The data strongly suggest that the influences of one metal exposure on the bioaccumulation of other metals/metalloids need to be considered in interpreting body concentrations of the elements in the biomonitors. Cd exposure had little effect on bivalve proteomes, and the identified proteins were insufficient to explain the observed disruption of trace element metabolism. However, protein expression signatures composed of the altered proteins could distinguish the clams and the mussels with different body Cd levels. The strong up-regulation of galectin in Cd-exposed oysters indicated the protein as a novel biomarker in environmental monitoring.

  20. Rocky Mountain Spotted Fever (For Parents)

    MedlinePlus

    ... Safety for the Whole Family Evaluate Your Child's Lyme Disease Risk Lyme Disease Lyme Disease Hey! A Tick Bit Me! Bug Bites and Stings Rocky Mountain Spotted Fever Lyme Disease Contact Us Print Resources Send to a friend ...

  1. Kepler Discovers Its First Rocky Planet

    NASA Video Gallery

    NASA's Kepler mission confirmed the discovery of its first rocky planet, named Kepler-10b. Measuring 1.4 times the size of Earth, it is the smallest planet ever discovered outside our solar system....

  2. Effects of changing sea ice on marine mammals and subsistence hunters in northern Alaska from traditional knowledge interviews

    PubMed Central

    Quakenbush, Lori T.; Nelson, Mark

    2016-01-01

    Marine mammals are important sources of food for indigenous residents of northern Alaska. Changing sea ice patterns affect the animals themselves as well as access to them by hunters. Documenting the traditional knowledge of Iñupiaq and Yupik hunters concerning marine mammals and sea ice makes accessible a wide range of information relevant to understanding the ecosystem to which humans belong. We interviewed hunters in 11 coastal villages from the northern Bering Sea to the Beaufort Sea. Hunters reported extensive changes in sea ice and weather that have affected the timing of marine mammal migrations, their distribution and behaviour and the efficacy of certain hunting methods. Amidst these changes, however, hunters cited offsetting technological benefits, such as more powerful and fuel-efficient outboard engines. Other concerns included potential impacts to subsistence hunting from industrial activity such as shipping and oil and gas development. While hunters have been able to adjust to some changes, continued environmental changes and increased disturbance from human activity may further challenge their ability to acquire food in the future. There are indications, however, that innovation and flexibility provide sources of resilience. PMID:27555644

  3. Effects of changing sea ice on marine mammals and subsistence hunters in northern Alaska from traditional knowledge interviews.

    PubMed

    Huntington, Henry P; Quakenbush, Lori T; Nelson, Mark

    2016-08-01

    Marine mammals are important sources of food for indigenous residents of northern Alaska. Changing sea ice patterns affect the animals themselves as well as access to them by hunters. Documenting the traditional knowledge of Iñupiaq and Yupik hunters concerning marine mammals and sea ice makes accessible a wide range of information relevant to understanding the ecosystem to which humans belong. We interviewed hunters in 11 coastal villages from the northern Bering Sea to the Beaufort Sea. Hunters reported extensive changes in sea ice and weather that have affected the timing of marine mammal migrations, their distribution and behaviour and the efficacy of certain hunting methods. Amidst these changes, however, hunters cited offsetting technological benefits, such as more powerful and fuel-efficient outboard engines. Other concerns included potential impacts to subsistence hunting from industrial activity such as shipping and oil and gas development. While hunters have been able to adjust to some changes, continued environmental changes and increased disturbance from human activity may further challenge their ability to acquire food in the future. There are indications, however, that innovation and flexibility provide sources of resilience.

  4. Impacts of Climate Variability and Change on (Marine) Animals: Physiological Underpinnings and Evolutionary Consequences.

    PubMed

    Pörtner, Hans O; Gutt, Julian

    2016-07-01

    Understanding thermal ranges and limits of organisms becomes important in light of climate change and observed effects on ecosystems as reported by the IPCC (2014). Evolutionary adaptation to temperature is presently unable to keep animals and other organisms in place; if they can these rather follow the moving isotherms. These effects of climate change on aquatic and terrestrial ecosystems have brought into focus the mechanisms by which temperature and its oscillations shape the biogeography and survival of species. For animals, the integrative concept of oxygen and capacity limited thermal tolerance (OCLTT) has successfully characterized the sublethal limits to performance and the consequences of such limits for ecosystems. Recent models illustrate how routine energy demand defines the realized niche. Steady state temperature-dependent performance profiles thus trace the thermal window and indicate a key role for aerobic metabolism, and the resulting budget of available energy (power), in defining performance under routine conditions, from growth to exercise and reproduction. Differences in the performance and productivity of marine species across latitudes relate to changes in mitochondrial density, capacity, and other features of cellular design. Comparative studies indicate how and why such mechanisms underpinning OCLTT may have developed on evolutionary timescales in different climatic zones and contributed to shaping the functional characteristics and species richness of the respective fauna. A cause-and-effect understanding emerges from considering the relationships between fluctuations in body temperature, cellular design, and performance. Such principles may also have been involved in shaping the functional characteristics of survivors in mass extinction events during earth's history; furthermore, they may provide access to understanding the evolution of endothermy in mammals and birds. Accordingly, an understanding is emerging how climate changes and

  5. From Greenhouse to Icehouse: Marine and Terrestrial Palynological Evidence for Climatic and Oceanic Change Through the Cenozoic of the Arctic

    NASA Astrophysics Data System (ADS)

    Bujak, J. P.; Brinkhuis, H.

    2004-12-01

    The marine and terrestrial biotas of northern Alaska and the Canadian Beaufort Mackenzie Basin (BMB) are intimately linked to changes in the climate and oceanography of the region. These changes can be reconstructed using palynological data from surface sections and numerous exploration wells drilled in the region over the past 30 years. During the Late Triassic to Early Eocene, marine dinoflagellate cyst (dinocyst) and terrestrial miospore (pollen and spore) palynomorphs were diverse and abundant across the region, reflecting the presence of a relatively warm and productive polar ocean that was fringed by extensive forests. The region was heated by northward-flowing Pacific currents, but lay north of the Arctic Circle and had seasonal 24 hour winter darkness and summer daylight. No modern analogue exists for this environment. A dramatic change occurred at the end of the Early Eocene as global climate shifted from the greenhouse towards the modern icehouse world. This had a particularly strong effect in high latitudes. A succession of major extinction events reflected falling sea and air temperatures in the Arctic and progressively eliminated marine and terrestrial species from the region. These events can be correlated with Eocene cooling steps known from the North Atlantic, where they had a milder effect, and provide a chronostratigraphic link between the regions. By Oligocene time the Arctic populations were strongly impoverished, but Miocene warming permitted the immigration of cold-temperate species including marine dinoflagellates and terrestrial angiosperms. Following this warm phase, the marine and terrestrial populations became increasingly restricted as air and water temperatures fell during the Plio-Pleistocene, leading to the modern highly endemic Arctic biotas.

  6. Idaho National Engineering Laboratory code assessment of the Rocky Flats transuranic waste

    SciTech Connect

    1995-07-01

    This report is an assessment of the content codes associated with transuranic waste shipped from the Rocky Flats Plant in Golden, Colorado, to INEL. The primary objective of this document is to characterize and describe the transuranic wastes shipped to INEL from Rocky Flats by item description code (IDC). This information will aid INEL in determining if the waste meets the waste acceptance criteria (WAC) of the Waste Isolation Pilot Plant (WIPP). The waste covered by this content code assessment was shipped from Rocky Flats between 1985 and 1989. These years coincide with the dates for information available in the Rocky Flats Solid Waste Information Management System (SWIMS). The majority of waste shipped during this time was certified to the existing WIPP WAC. This waste is referred to as precertified waste. Reassessment of these precertified waste containers is necessary because of changes in the WIPP WAC. To accomplish this assessment, the analytical and process knowledge available on the various IDCs used at Rocky Flats were evaluated. Rocky Flats sources for this information include employee interviews, SWIMS, Transuranic Waste Certification Program, Transuranic Waste Inspection Procedure, Backlog Waste Baseline Books, WIPP Experimental Waste Characterization Program (headspace analysis), and other related documents, procedures, and programs. Summaries are provided of: (a) certification information, (b) waste description, (c) generation source, (d) recovery method, (e) waste packaging and handling information, (f) container preparation information, (g) assay information, (h) inspection information, (i) analytical data, and (j) RCRA characterization.

  7. Resolving Variations in Continental Weathering Flux From Changes in Continental Source Using Marine Radiogenic Isotope Records

    NASA Astrophysics Data System (ADS)

    Burton, K. W.; Gannoun, A.; Allegre, C. J.; Christensen, J. N.; Hein, J. R.

    2005-12-01

    Determining the past record of chemical weathering is essential for understanding changes in climate and atmospheric CO2, such as those that occur throughout the Cenozoic (the last 65 Million years) (e.g. 1). Many natural radiogenic isotopes in seawater are sensitive to variations in chemical weathering (e.g. 2), but none alone can distinguish such changes from those caused by variations in erosional source. Comparison of isotope systems with different sources and different behaviour in seawater can however resolve such effects. This study presents multi-isotope records for both long (Cenozoic) and short (glacial-interglacial) timescales, and these are used to deconvolve changes in the balance of continental weathering from those related to changes in source. Comparison of a high-resolution marine 187Os/188Os record for the Cenozoic with Pb, Hf and Nd isotopes (from the same sample [3-5]) strongly suggests that for much of the Cenozoic isotope variations reflect a simple change in the balance of continental versus hydrothermal input, with little change in continental source. Changes in this relationship at the middle Miocene climate transition, at least to some extent, reflect a major reorganisation of ocean circulation [6] resulting in a shift of the geographical sources of weathered continental material. Comparison of Sr, Os and Nd records for the past 140 ka from the Bay of Bengal suggest that changes in the Nd isotope composition of seawater are climatically driven by local changes in the composition of riverine input, whereas variations in Os likely reflect a change in the balance of continental weathering. These studies highlight the difficulties of using a single radiogenic isotope system as a proxy for continental weathering or source, but show that by using a combination of radiogenic isotopes with different sources to the oceans, different behaviour during weathering, and different residence times in the oceans it may sometimes be possible to resolve such

  8. Modeling Hydrodynamic Changes Due to Marine Hydrokinetic Power Production: Community Outreach and Education

    NASA Astrophysics Data System (ADS)

    James, S. C.; Jones, C.; Roberts, J.

    2013-12-01

    Power generation with marine hydrokinetic (MHK) turbines is receiving growing global interest. Because of reasonable investment, maintenance, reliability, and environmental friendliness, this technology can contribute to national (and global) energy markets and is worthy of research investment. Furthermore, in remote areas, small-scale MHK energy from river, tidal, or ocean currents can provide a local power supply. The power-generating capacity of MHK turbines will depend, among other factors, upon the turbine type and number and the local flow velocities. There is an urgent need for deployment of practical, accessible tools and techniques to help the industry optimize MHK array layouts while establishing best sitting and design practices that minimize environmental impacts. Sandia National Laboratories (SNL) has modified the open-source flow and transport Environmental Fluid Dynamics Code (EFDC) to include the capability of simulating the effects of MHK power production. Upon removing energy (momentum) from the system, changes to the local and far-field flow dynamics can be estimated (e.g., flow speeds, tidal ranges, flushing rates, etc.). The effects of these changes on sediment dynamics and water quality can also be simulated using this model. Moreover, the model can be used to optimize MHK array layout to maximize power capture and minimize environmental impacts. Both a self-paced tutorial and in-depth training course have been developed as part of an outreach program to train academics, technology developers, and regulators in the use and application of this software. This work outlines SNL's outreach efforts using this modeling framework as applied to two specific sites where MHK turbines have been deployed.

  9. Changes in trace elements during lactation in a marine top predator, the grey seal.

    PubMed

    Habran, Sarah; Pomeroy, Paddy P; Debier, Cathy; Das, Krishna

    2013-01-15

    Lactation in pinnipeds represents the most significant cost to mothers during the reproductive cycle. Dynamics of trace elements and their mobilization associated with energy reserves during such an intense physiological process remains poorly understood in marine mammals. The changes in tissue concentrations of 11 elements (Ca, Cd, Cr, Cu, Fe, Hg, Ni, Pb, Se, V, and Zn) were investigated in a longitudinal study during the lactation period and during the post-weaning fast period. Blood, milk, blubber, and hair samples were collected sequentially from 21 mother-pup pairs of grey seals (Halichoerus grypus) from the Isle of May in Scotland. Maternal transfer through the milk was observed for all trace elements, except for Cd. As an indicator of the placental transfer, levels in pup lanugo (natal coat) revealed also the existence of maternal transfer and accumulation of all assayed trace elements during the foetal development. The placental and mammary barriers against non-essential metal transfer to offspring appear to be absent or weak in grey seals. Examining the contamination levels showed that this grey seal population seems more highly exposed to Pb than other phocid populations (2.2 mg/kg dw of grey seal hair). In contrast, blood and hair levels reflected a lower Hg exposure in grey seals from the Isle of May than in harbour seals from the southeastern North Sea. This study also showed that trace element concentrations in blood and blubber could change rapidly over the lactation period. Such physiological processes must be considered carefully during biomonitoring of trace elements, and potential impacts that rapid fluctuations in concentrations can exert on seal health should be further investigated.

  10. Predicting the effects of climate change on marine communities and the consequences for fisheries

    NASA Astrophysics Data System (ADS)

    Jennings, Simon; Brander, Keith

    2010-02-01

    Climate effects on the structure and function of marine communities have received scant attention. The few existing approaches for predicting climate effects suggest that community responses might be predicted from the responses of component populations. These approaches require a very complex understanding of ecological interactions among populations. An alternate and informative parallel process is to ask whether it is possible to make predictions about community level responses to climate that are independent of knowledge about the identity and dynamics of component populations. We propose that it is possible to make such predictions, based on knowledge of the processes that determine the size-structure of communities. We suggest that theory that relates metabolic scaling, predator-prey interactions and energy transfer in size-based food webs, allows the size-structure and productivity of communities across a range of trophic levels to be predicted, provided that predictions of the effects of climate on primary production are available. One simple application of the community-focused predictions is to ask whether predictions of the size composition and abundance of populations for alternate climate scenarios are compatible with predictions for the size composition and relative abundance of communities. More sophisticated treatments could predict the effects of climate scenarios on multiple interacting populations and compare their combined size-abundance structure and production with that predicted for the community under the same climate scenario. The main weakness of the community approach is that the methods predict abundance and production by size-class rather than taxonomic group, and society would be particularly concerned if climate driven changes had a strong effect on the relative production of fishable and non-fishable species in the community. The main strength of the community approach is that it provides widely applicable 'null' models for assessing

  11. Response of marine copepods to a changing tropical environment: winners, losers and implications

    PubMed Central

    Chew, Li Lee

    2016-01-01

    Background. Climate change concurrent with anthropogenic disturbances can initiate serial changes that reverberate up the food chain with repercussions for fisheries. To date, there is no information available concerning the combined effects of global warming and human impacts on tropical marine food webs. While temperate copepods respond differently to warming and environmental stressors, the extent to which tropical copepods can adapt to rising temperature of already warm waters remains unknown. We hypothesize that sea warming and other anthropogenic disturbances over the long term will have the greatest impact on the copepod community in nearshore waters where their effects are accentuated, and therefore vulnerable and resilient species could be identified. Methods. Zooplankton samples were collected during two time periods (1985–86 and 2014–15) interposed by marked anthropogenic disturbances, and at the same five stations located progressively from inshore to offshore in Klang Strait, Malaysia, following the asymmetrical before-after-control-impact (BACI) design. Copepods were identified to species, and results were interpreted by univariate (ANOVA) and multivariate (PERMANOVA, PCO) analyses of the computed species abundance and diversity measures. Results. Copepod total abundance was not significantly different among stations but higher after disturbance than before disturbance. However, changes in the abundance of particular species and the community structure between time periods were dramatic. Coastal large-bodied calanoid species (e.g., Acartia spinicauda, Calanopia thompsoni, Pseudodiaptomus bowmani and Tortanus forcipatus) were the most vulnerable group to disturbance. This however favored the opportunistic species (e.g., Oithona simplex, O. attenuata, Hemicyclops sp., Pseudomacrochiron sp. and Microsetella norvegica). Small-bodied copepods (e.g., Paracalanus sp., Parvocalanus crassirostris and Euterpina acutifrons) were unaffected. Centropages

  12. Response of marine copepods to a changing tropical environment: winners, losers and implications.

    PubMed

    Chew, Li Lee; Chong, Ving Ching

    2016-01-01

    Background. Climate change concurrent with anthropogenic disturbances can initiate serial changes that reverberate up the food chain with repercussions for fisheries. To date, there is no information available concerning the combined effects of global warming and human impacts on tropical marine food webs. While temperate copepods respond differently to warming and environmental stressors, the extent to which tropical copepods can adapt to rising temperature of already warm waters remains unknown. We hypothesize that sea warming and other anthropogenic disturbances over the long term will have the greatest impact on the copepod community in nearshore waters where their effects are accentuated, and therefore vulnerable and resilient species could be identified. Methods. Zooplankton samples were collected during two time periods (1985-86 and 2014-15) interposed by marked anthropogenic disturbances, and at the same five stations located progressively from inshore to offshore in Klang Strait, Malaysia, following the asymmetrical before-after-control-impact (BACI) design. Copepods were identified to species, and results were interpreted by univariate (ANOVA) and multivariate (PERMANOVA, PCO) analyses of the computed species abundance and diversity measures. Results. Copepod total abundance was not significantly different among stations but higher after disturbance than before disturbance. However, changes in the abundance of particular species and the community structure between time periods were dramatic. Coastal large-bodied calanoid species (e.g., Acartia spinicauda, Calanopia thompsoni, Pseudodiaptomus bowmani and Tortanus forcipatus) were the most vulnerable group to disturbance. This however favored the opportunistic species (e.g., Oithona simplex, O. attenuata, Hemicyclops sp., Pseudomacrochiron sp. and Microsetella norvegica). Small-bodied copepods (e.g., Paracalanus sp., Parvocalanus crassirostris and Euterpina acutifrons) were unaffected. Centropages

  13. Detecting changes in marine responses to ENSO from 850 to 2100 C.E.: Insights from the ocean carbon cycle

    NASA Astrophysics Data System (ADS)

    Keller, Kathrin M.; Joos, Fortunat; Lehner, Flavio; Raible, Christoph C.

    2015-01-01

    It is open whether El Niño-Southern Oscillation (ENSO) varies under climate change and how potential changes in the marine system are detectable. Here differences in the influence of ENSO on biogeochemical tracers, pH, productivity, and ocean temperature are analyzed in a continuous 850-2100 Common Era (C.E.) simulation with the Community Earth System Model. The modeled variance in ENSO amplitude is significantly higher during the Maunder Minimum cold than during the 21st century warm period. ENSO-driven anomalies in global air-sea CO2 flux and marine productivity are two to three times lower, and ocean tracer anomalies are generally weaker in the 21st century. Significant changes are detectable in both surface and subsurface waters and are earlier verifiable and more widespread for carbon cycle tracers than for temperature. This suggests that multitracer observations of both physical and biogeochemical variables would enable an earlier detection of potential changes in marine ENSO responses than temperature-only data.

  14. Estimating effects of tidal power projects and climate change on threatened and endangered marine species and their food web.

    PubMed

    Busch, D Shallin; Greene, Correigh M; Good, Thomas P

    2013-12-01

    Marine hydrokinetic power projects will operate as marine environments change in response to increased atmospheric carbon dioxide concentrations. We considered how tidal power development and stressors resulting from climate change may affect Puget Sound species listed under the U.S. Endangered Species Act (ESA) and their food web. We used risk tables to assess the singular and combined effects of tidal power development and climate change. Tidal power development and climate change posed risks to ESA-listed species, and risk increased with incorporation of the effects of these stressors on predators and prey of ESA-listed species. In contrast, results of a model of strikes on ESA-listed species from turbine blades suggested that few ESA-listed species are likely to be killed by a commercial-scale tidal turbine array. We applied scenarios to a food web model of Puget Sound to explore the effects of tidal power and climate change on ESA-listed species using more quantitative analytical techniques. To simulate development of tidal power, we applied results of the blade strike model. To simulate environmental changes over the next 50 years, we applied scenarios of change in primary production, plankton community structure, dissolved oxygen, ocean acidification, and freshwater flooding events. No effects of tidal power development on ESA-listed species were detected from the food web model output, but the effects of climate change on them and other members of the food web were large. Our analyses exemplify how natural resource managers might assess environmental effects of marine technologies in ways that explicitly incorporate climate change and consider multiple ESA-listed species in the context of their ecological community. Estimación de los Efectos de Proyectos de Energía de las Mareas y el Cambio Climático sobre Especies Marinas Amenazadas y en Peligro y su Red Alimentaria.

  15. Climate change, reproductive performance and diet composition of marine birds in the southern California Current system, 1969 1997

    NASA Astrophysics Data System (ADS)

    Sydeman, William J.; Hester, Michelle M.; Thayer, Julie A.; Gress, Franklin; Martin, Paige; Buffa, Joelle

    We studied the effects of low-frequency climate change on the reproductive performance of 11 species of marine bird in the southern California Current system, 1969-1997. Reproductive performance of Brown Pelican ( Pelecanus occidentalis) and Double-crested Cormorant ( Phalacrocrax auritus) in southern California demonstrated an increase in the 1970s and early 1980s, attributable to recovery from organochlorine contamination (primarily DDE). Brandt's Cormorant ( Phalacrocorax penicillatus) in central California was the only species to demonstrate a secular increase in performance through time, a pattern that remains unexplained. Ashy Storm-petrel ( Oceanodroma homochroa) and Pelagic Cormorant ( Phalacrocorax pelagicus) demonstrated curvilinear patterns of change, with decreasing reproductive performance in the past decade. All other species including Western Gull ( Larus occidentalis), Pigeon Guillemot ( Cepphus columba), Xantus's Murrelet ( Synthiloboramphus hypoleucus), Common Murre ( Uria aalge), Cassin's Auklet ( Ptychoramphus aleuticus) and Rhinoceros Auklet ( Cerorhinca monocerata) showed diminishing reproductive performance through time. Patterns of change for the murre and auklets were not significant, presumably because of a lack of reproductive variation for these species, which display a conservative breeding effort (i.e. single-egg clutches). Changes in the birds' abilities to provision young and maintain chick survival during May-July each year appeared most closely related to overall changes in reproductive performance. Dietary change indicated a decline in use of juvenile rockfish ( Sebastes spp.) by marine birds in central California. There was also significant interannual variability in consumption of juvenile rockfish and the euphausiid Thysanoessa spinifera. Patterns of change in marine bird reproductive performance were generally concordant between southern and central California after considering the period of recovery for Brown Pelican and

  16. GEOLOGIC ASPECTS OF TIGHT GAS RESERVOIRS IN THE ROCKY MOUNTAIN REGION.

    USGS Publications Warehouse

    Spencer, Charles W.

    1985-01-01

    The authors describe some geologic characteristics of tight gas reservoirs in the Rocky Mountain region. These reservoirs usually have an in-situ permeability to gas of 0. 1 md or less and can be classified into four general geologic and engineering categories: (1) marginal marine blanket, (2) lenticular, (3) chalk, and (4) marine blanket shallow. Microscopic study of pore/permeability relationships indicates the existence of two varieties of tight reservoirs. One variety is tight because of the fine grain size of the rock. The second variety is tight because the rock is relatively tightly cemented and the pores are poorly connected by small pore throats and capillaries.

  17. Isotopic Evidence for Large Scale Temporal Changes in the Cenozoic Marine Lithium Cycle

    NASA Astrophysics Data System (ADS)

    Misra, S.; Froelich, P. N.

    2009-12-01

    The δ7Li of seawater (~31.0‰) is controlled by a balance between riverine (δ7LiRiv~23‰) and hydrothermal (δ7LiHT~5.6‰) inputs and large fractionation (ΔSW-SED ~16‰) during removal into marine authigenic clays ((δ7LiSED~15‰). The seawater δ7Li (δ7LiSW) is thus sensitive to changes in these sources and sinks on time scales of the Li residence time in seawatwer, τLi~2 Ma. Planktonic foraminifera faithfully record such variations in δ7LiSW [Hathorne & James, 2006]. A long-term history of δ7LiSW evolution reconstructed from planktonic foraminifera might help identify changes in seawater chemistry and those factors driving variations of oceanic silica mass balances linked to continental and sea floor/hydrothermal weathering, adding texture to the uplift-weathering paradigms evoked by records of 87/86Sr [Hess et al., 1986; Hodell et al., 1991], 44/40Ca [Griffith et al., 2008], and 187/188Os [Peucker-Ehrenbrink & Ravizza, 2000]. A high-resolution Neogene record of seawater Li isotopes from super-cleaned planktonic forams (sites 758, 926 & 588) reveals that δ7LiSW rose from 26.5‰ during Mid-Miocene (16Ma) to 30.8‰ in Late Miocene (7Ma). This rise in δ7LiSW is preceded (24Ma-16Ma) and followed (7Ma to present) by long periods of almost constant δ7LiSW of 26.5‰ and 30.8‰ respectively. This quasi-linear 4‰ increase of δ7LiSW within eight Ma, which is very large and confirmed by individual species and ‘bulk’ forams, must reflect large changes in the balance between inputs to the ocean from riverine and hydrothermal sources and outputs via authigenic clay formation, and/or changes in δ7Li of the sources or sinks. A simple mass balance suggests that a 4‰ increase in δ7LiSW over eight Ma would require: (1) a shift in the average ΔSW-SED (authigenic clay) from 11 to 16‰ (diagenesis); (2a) an increase in the river Li-flux from 3.2 to 8x109 moles/yr; (2b) an increase in δ7LiRiv from 16‰ to 23‰; (3a) a decrease in the hydrothermal Li

  18. Redox conditions and marine microbial community changes during the end-Ordovician mass extinction event

    NASA Astrophysics Data System (ADS)

    Smolarek, Justyna; Marynowski, Leszek; Trela, Wiesław; Kujawski, Piotr; Simoneit, Bernd R. T.

    2017-02-01

    The end-Ordovician (Hirnantian) crisis is the first globally distinct extinction during the Phanerozoic, but its causes are still not fully known. Here, we present an integrated geochemical and petrographic analysis to understand the sedimentary conditions taking place before, during and after the Late Ordovician ice age. New data from the Zbrza (Holy Cross Mountains) and Gołdap (Baltic Depression) boreholes shows that, like in other worldwide sections, the total organic carbon (TOC) content is elevated in the upper Katian and uppermost Hirnantian to Rhudannian black shales, but depleted (below 1%) during most of the Hirnantian. Euxinic conditions occurred in the photic zone in both TOC-rich intervals. This is based on the maleimide distribution, occurrence of aryl isoprenoids and isorenieratane, as well as a dominance of tiny pyrite framboids. Euxinic conditions were interrupted by the Hirnantian regression caused by glaciation. Sedimentation on the deep shelf changed to aerobic probably due to intense thermohaline circulation. Euxinia in the water column occurred directly during the time associated with the second pulse of the mass extinction with a termination of the end-Ordovician glaciation and sea level rise just at the Ordovician/Silurian (O/S) boundary. In contrast, we suggest based on inorganic proxies that bottom water conditions were generally oxic to dysoxic due to upwelling in the Rheic Ocean. The only episode of seafloor anoxia in the Zbrza basin was found at the O/S boundary, where all inorganic indicators showed elevated values typical for anoxia (U/Th > 1.25; V/Cr > 4.25; V/(V + Ni): 0.54-0.82 and Mo > 10-25 ppm). Significant differences in hopanes to steranes ratio and in C27-C29 sterane distribution between the Katian, Rhudannian and Hirnantian deposits indicate changes in marine microbial communities triggered by sharp climate change and Gondwana glaciation. The increase from biomarkers of cyanobacteria (2α-methylhopanes) after the O

  19. Holocene changes in the trophic ecology of an apex marine predator in the South Atlantic Ocean.

    PubMed

    Vales, Damián G; Cardona, Luis; Zangrando, Atilio F; Borella, Florencia; Saporiti, Fabiana; Goodall, R Natalie P; de Oliveira, Larissa Rosa; Crespo, Enrique A

    2017-02-01

    Predators may modify their diets as a result of both anthropogenic and natural environmental changes. Stable isotope ratios of nitrogen and carbon in bone collagen have been used to reconstruct the foraging ecology of South American fur seals (Arctocephalus australis) in the southwestern South Atlantic Ocean since the Middle Holocene, a region inhabited by hunter-gatherers by millennia and modified by two centuries of whaling, sealing and fishing. Results suggest that the isotopic niche of fur seals from Patagonia has not changed over the last two millennia (average for the period: δ(13)C2200-0BP = -13.4 ± 0.5‰, δ(15)N2200-0BP = 20.6 ± 1.1‰). Conversely, Middle Holocene fur seals fed more pelagically than their modern conspecifics in the Río de la Plata region (δ(13)C7000BP = -15.9 ± 0.6‰ vs. δ(13)CPRESENT = -13.5 ± 0.8‰) and Tierra del Fuego (δ(13)C6400-4300BP = -15.4 ± 0.5‰ vs. δ(13)CPRESENT = -13.2 ± 0.7‰). In the latter region, Middle Holocene fur seals also fed at a higher trophic level than their modern counterparts (δ(15)N6400-4300BP = 20.5 ± 0.5‰ vs. δ(15)NPRESENT = 19.0 ± 1.6‰). Nevertheless, a major dietary shift was observed in fur seals from Tierra del Fuego during the nineteenth century (δ(13)C100BP = -17.2 ± 0.3‰, δ(15)N100BP = 18.6 ± 0.7‰), when marine primary productivity plummeted and the fur seal population was decimated by sealing. Disentangling the relative roles of natural and anthropogenic factors in explaining this dietary shift is difficult, but certainly the trophic position of fur seals has changed through the Holocene in some South Atlantic regions.

  20. Prevalence of algal toxins in Alaskan marine mammals foraging in a changing arctic and subarctic environment.

    PubMed

    Lefebvre, Kathi A; Quakenbush, Lori; Frame, Elizabeth; Huntington, Kathy Burek; Sheffield, Gay; Stimmelmayr, Raphaela; Bryan, Anna; Kendrick, Preston; Ziel, Heather; Goldstein, Tracey; Snyder, Jonathan A; Gelatt, Tom; Gulland, Frances; Dickerson, Bobette; Gill, Verena

    2016-05-01

    Current climate trends resulting in rapid declines in sea ice and increasing water temperatures are likely to expand the northern geographic range and duration of favorable conditions for harmful algal blooms (HABs), making algal toxins a growing concern in Alaskan marine food webs. Two of the most common HAB toxins along the west coast of North America are the neurotoxins domoic acid (DA) and saxitoxin (STX). Over the last 20 years, DA toxicosis has caused significant illness and mortality in marine mammals along the west coast of the USA, but has not been reported to impact marine mammals foraging in Alaskan waters. Saxitoxin, the most potent of the paralytic shellfish poisoning toxins, has been well-documented in shellfish in the Aleutians and Gulf of Alaska for decades and associated with human illnesses and deaths due to consumption of toxic clams. There is little information regarding exposure of Alaskan marine mammals. Here, the spatial patterns and prevalence of DA and STX exposure in Alaskan marine mammals are documented in order to assess health risks to northern populations including those species that are important to the nutritional, cultural, and economic well-being of Alaskan coastal communities. In this study, 905 marine mammals from 13 species were sampled including; humpback whales, bowhead whales, beluga whales, harbor porpoises, northern fur seals, Steller sea lions, harbor seals, ringed seals, bearded seals, spotted seals, ribbon seals, Pacific walruses, and northern sea otters. Domoic acid was detected in all 13 species examined and had the greatest prevalence in bowhead whales (68%) and harbor seals (67%). Saxitoxin was detected in 10 of the 13 species, with the highest prevalence in humpback whales (50%) and bowhead whales (32%). Pacific walruses contained the highest concentrations of both STX and DA, with DA concentrations similar to those detected in California sea lions exhibiting clinical signs of DA toxicosis (seizures) off the coast

  1. Changes of the elemental distributions in marine diatoms as a reporter of sample preparation artefacts. A nuclear microscopy application

    NASA Astrophysics Data System (ADS)

    Godinho, R. M.; Cabrita, M. T.; Alves, L. C.; Pinheiro, T.

    2015-04-01

    Studies of the elemental composition of whole marine diatoms cells have high interest as they constitute a direct measurement of environmental changes, and allow anticipating consequences of anthropogenic alterations to organisms, ecosystems and global marine geochemical cycles. Nuclear microscopy is a powerful tool allowing direct measurement of whole cells giving qualitative imaging of distribution, and quantitative determination of intracellular concentration. Major obstacles to the analysis of marine microalgae are high medium salinity and the recurrent presence of extracellular exudates produced by algae to maintain colonies in natural media and in vitro. The objective of this paper was to optimize the methodology of sample preparation of marine unicellular algae for elemental analysis with nuclear microscopy, allowing further studies on cellular response to metals. Primary cultures of Coscinodiscus wailesii maintained in vitro were used to optimize protocols for elemental analysis with nuclear microscopy techniques. Adequate cell preparation procedures to isolate the cells from media components and exudates were established. The use of chemical agents proved to be inappropriate for elemental determination and for intracellular morphological analysis. The assessment of morphology and elemental partitioning in cell compartments obtained with nuclear microscopy techniques enabled to infer their function in natural environment and imbalances in exposure condition. Exposure to metal affected C. wailesii morphology and internal elemental distribution.

  2. Metal release from contaminated estuarine sediment under pH changes in the marine environment.

    PubMed

    Martín-Torre, M Camino; Payán, M Cruz; Verbinnen, Bram; Coz, Alberto; Ruiz, Gema; Vandecasteele, Carlo; Viguri, Javier R

    2015-04-01

    The contaminant release from estuarine sediment due to pH changes was investigated using a modified CEN/TS 14429 pH-dependence leaching test. The test is performed in the range of pH values of 0-14 using deionised water and seawater as leaching solutions. The experimental conditions mimic different circumstances of the marine environment due to the global acidification, carbon dioxide (CO2) leakages from carbon capture and sequestration technologies, and accidental chemical spills in seawater. Leaching test results using seawater as leaching solution show a better neutralisation capacity giving slightly lower metal leaching concentrations than when using deionised water. The contaminated sediment shows a low base-neutralisation capacity (BNCpH 12 = -0.44 eq/kg for deionised water and BNCpH 12 = -1.38 eq/kg for seawater) but a high acid-neutralisation capacity when using deionised water (ANCpH 4 = 3.58 eq/kg) and seawater (ANCpH 4 = 3.97 eq/kg). Experimental results are modelled with the Visual MINTEQ geochemical software to predict metal release from sediment using both leaching liquids. Surface adsorption to iron- and aluminium-(hydr)oxides was applied for all studied elements. The consideration of the metal-organic matter binding through the NICA-Donnan model and Stockholm Humic Model for lead and copper, respectively, improves the former metal release prediction. Modelled curves can be useful for the environmental impact assessment of seawater acidification due to its match with the experimental values.

  3. 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.

  4. Multi-generational responses of a marine polychaete to a rapid change in seawater pCO2.

    PubMed

    Rodríguez-Romero, Araceli; Jarrold, Michael D; Massamba-N'Siala, Gloria; Spicer, John I; Calosi, Piero

    2016-10-01

    Little is known of the capacity that marine metazoans have to evolve under rapid p CO 2 changes. Consequently, we reared a marine polychaete, Ophryotrocha labronica, previously cultured for approximately 33 generations under a low/variable pH regime, under elevated and low p CO 2 for six generations. The strain used was found to be tolerant to elevated p CO 2 conditions. In generations F1 and F2 females' fecundity was significantly lower in the low p CO 2 treatment. However, from generation F3 onwards there were no differences between p CO 2 treatments, indicating that trans-generational effects enabled the restoration and maintenance of reproductive output. Whilst the initial fitness recovery was likely driven by trans-generational plasticity (TGP), the results from reciprocal transplant assays, performed using F7 individuals, made it difficult to disentangle between whether TGP had persisted across multiple generations, or if evolutionary adaptation had occurred. Nonetheless, both are important mechanisms for persistence under climate change. Overall, our study highlights the importance of multi-generational experiments in more accurately determining marine metazoans' responses to changes in p CO 2, and strengthens the case for exploring their use in conservation, by creating specific p CO 2 tolerant strains of keystone ecosystem species.

  5. Do drivers of biodiversity change differ in importance across marine and terrestrial systems - Or is it just different research communities' perspectives?

    PubMed

    Knapp, Sonja; Schweiger, Oliver; Kraberg, Alexandra; Asmus, Harald; Asmus, Ragnhild; Brey, Thomas; Frickenhaus, Stephan; Gutt, Julian; Kühn, Ingolf; Liess, Matthias; Musche, Martin; Pörtner, Hans-O; Seppelt, Ralf; Klotz, Stefan; Krause, Gesche

    2017-01-01

    Cross-system studies on the response of different ecosystems to global change will support our understanding of ecological changes. Synoptic views on the planet's two main realms, the marine and terrestrial, however, are rare, owing to the development of rather disparate research communities. We combined questionnaires and a literature review to investigate how the importance of anthropogenic drivers of biodiversity change differs among marine and terrestrial systems and whether differences perceived by marine vs. terrestrial researchers are reflected by the scientific literature. This included asking marine and terrestrial researchers to rate the relevance of different drivers of global change for either marine or terrestrial biodiversity. Land use and the associated loss of natural habitats were rated as most important in the terrestrial realm, while the exploitation of the sea by fishing was rated as most important in the marine realm. The relevance of chemicals, climate change and the increasing atmospheric concentration of CO2 were rated differently for marine and terrestrial biodiversity respectively. Yet, our literature review provided less evidence for such differences leading to the conclusion that while the history of the use of land and sea differs, impacts of global change are likely to become increasingly similar.

  6. Cutaneous histopathology of Rocky Mountain spotted fever.

    PubMed

    Kao, G F; Evancho, C D; Ioffe, O; Lowitt, M H; Dumler, J S

    1997-11-01

    The dermatologic diagnosis of Rocky Mountain spotted fever (RMSF) is often presumptive; the clinical presentation includes skin rash and febrile illness with or without a clear history of tick bite. The characteristic cutaneous manifestations include a generalized skin eruption with purpuric, blanching or non-blanching macules and papules usually involving the extremities. Although skin biopsies are often performed to confirm the diagnosis, the spectrum of cutaneous histopathology in RMSF has not been well described. We studied a series of 26 cases of RMSF, of which 10 were surgical specimens and 16 were autopsies. The microscopic changes were correlated with the duration of illness. The main histopathologic feature was lymphohistiocytic capillaritis and venulitis with extravasation of erythrocytes, edema, predominantly perivascular and some interstitial infiltrate. Leukocytoclastic vasculitis (LCV) with neutrophilic infiltrate and nuclear dust was seen in 11 of 15 (73%) specimens from involved skin. These lesions with LCV also showed notable epidermal change including basal layer vacuolar degeneration with mild dermoepidermal interface lymphocytic exocytosis. Six lesions with LCV displayed focal fibrin thrombi and capillary wall necrosis. Apoptotic keratinocytes were noted in 3 lesions with LCV. Subepidermal blister was observed in the skin lesion of an autopsied patient with LCV changes. Another lesion of a fatal case with LCV also contained features of acute neutrophilic eccrine hidradenitis. Focal small nerve twig inflammation was noted in a third autopsy case with LCV. Plasma cells were seen in 6 of 34 specimens (18%); and eosinophils were observed in 3 (9%). The subcutaneous fat contained a mild perivascular inflammation and one case revealed focal lobular neutrophilic inflammation. Immunohistologic (IH) staining using polyclonal rabbit anti-Rickettsia rickettsii demonstrated positive staining of the organisms in the affected endothelial cells in all 12 cases

  7. Patterns of Mass Mortality among Rocky Shore Invertebrates across 100 km of Northeastern Pacific Coastline

    PubMed Central

    Jurgens, Laura J.; Rogers-Bennett, Laura; Raimondi, Peter T.; Schiebelhut, Lauren M.; Dawson, Michael N.; Grosberg, Richard K.; Gaylord, Brian

    2015-01-01

    Mass mortalities in natural populations, particularly those that leave few survivors over large spatial areas, may cause long-term ecological perturbations. Yet mass mortalities may remain undocumented or poorly described due to challenges in responding rapidly to unforeseen events, scarcity of baseline data, and difficulties in quantifying rare or patchily distributed species, especially in remote or marine systems. Better chronicling the geographic pattern and intensity of mass mortalities is especially critical in the face of global changes predicted to alter regional disturbance regimes. Here, we couple replicated post-mortality surveys with preceding long-term surveys and historical data to describe a rapid and severe mass mortality of rocky shore invertebrates along the north-central California coast of the northeastern Pacific Ocean. In late August 2011, formerly abundant intertidal populations of the purple sea urchin (Strongylocentrotus purpuratus, a well-known ecosystem engineer), and the predatory six-armed sea star (Leptasterias sp.) were functionally extirpated from ~100 km of coastline. Other invertebrates, including the gumboot chiton (Cryptochiton stelleri) the ochre sea star (Pisaster ochraceus), and subtidal populations of purple sea urchins also exhibited elevated mortality. The pattern and extent of mortality suggest the potential for long-term population, community, and ecosystem consequences, recovery from which may depend on the different dispersal abilities of the affected species. PMID:26039349

  8. Patterns of Mass Mortality among Rocky Shore Invertebrates across 100 km of Northeastern Pacific Coastline.

    PubMed

    Jurgens, Laura J; Rogers-Bennett, Laura; Raimondi, Peter T; Schiebelhut, Lauren M; Dawson, Michael N; Grosberg, Richard K; Gaylord, Brian

    2015-01-01

    Mass mortalities in natural populations, particularly those that leave few survivors over large spatial areas, may cause long-term ecological perturbations. Yet mass mortalities may remain undocumented or poorly described due to challenges in responding rapidly to unforeseen events, scarcity of baseline data, and difficulties in quantifying rare or patchily distributed species, especially in remote or marine systems. Better chronicling the geographic pattern and intensity of mass mortalities is especially critical in the face of global changes predicted to alter regional disturbance regimes. Here, we couple replicated post-mortality surveys with preceding long-term surveys and historical data to describe a rapid and severe mass mortality of rocky shore invertebrates along the north-central California coast of the northeastern Pacific Ocean. In late August 2011, formerly abundant intertidal populations of the purple sea urchin (Strongylocentrotus purpuratus, a well-known ecosystem engineer), and the predatory six-armed sea star (Leptasterias sp.) were functionally extirpated from ~100 km of coastline. Other invertebrates, including the gumboot chiton (Cryptochiton stelleri) the ochre sea star (Pisaster ochraceus), and subtidal populations of purple sea urchins also exhibited elevated mortality. The pattern and extent of mortality suggest the potential for long-term population, community, and ecosystem consequences, recovery from which may depend on the different dispersal abilities of the affected species.

  9. Polarimetry for rocky exoplanet characterization

    NASA Astrophysics Data System (ADS)

    Stam, Daphne; Karalidi, Theodora

    2013-04-01

    Since the first discovery of a planet around a solar-type star by Mayor & Queloz in 1995, several hundreds of exoplanets have been detected. Indeed, it appears that practically all Sun-like stars have planets. Inevitable, Earth-sized, rocky planets that orbit in their star's habitable zone, where temperatures could be just right to allow liquid water on a planet's surface, will be found. Liquid water is generally considered to be essential for the existence of life. Whether liquid water actually exists on a planet depends strongly on the atmosphere's thickness and characteristics, such as the surface pressure and composition. Famous examples in the Solar System are Venus and the Earth, with similar sizes, inner compositions and orbital radii, but wildly different surface conditions. The characterization of the atmospheres and/or surfaces of exoplanets will allow a comparison with Solar System planets and it will open up a treasure trove of knowledge about the formation and evolution of planetary atmospheres and surfaces, thanks to the vast range of orbital distances, planet sizes and ages that can be studied. Characterization will also allow studying conditions for life and ultimately the existence of life around other stars. Information about the upper atmospheres of close-in, hot, giant exoplanets, can be derived from measurements of the combined flux of the star and the planet, in particular when the planet is transiting its star. This method has also provided traces of an atmosphere around a large solid planet orbiting red dwarf star GJ1214. Detection and characterization of the atmospheres and/or surfaces of small, solid, Earth-like exoplanets in the habitable zones of Sun-like stars, is virtually impossible with transit observations. For these exiting planets, polarimetry appears to be a strong tool. Polarimetry helps the detection of exoplanets, because direct starlight is usually unpolarized, while starlight that has been reflected by a planet is usually

  10. Folding above faults, Rocky Mountains

    SciTech Connect

    McConnell, D.A. . Dept. of Geology)

    1992-01-01

    Asymmetric folds formed above basement faults can be observed throughout the Rocky Mountains. Several previous interpretations of the folding process made the implicit assumption that one or both fold hinges migrated or rolled'' through the steep forelimb of the fold as the structure evolved (rolling hinge model). Results of mapping in the Bighorn and Seminoe Mountains, WY, and Sangre de Cristo Range, CO, do not support this hypothesis. An alternative interpretation is presented in which fold hinges remained fixed in position during folding (fixed hinge model). Mapped folds share common characteristics: (1) axial traces of the folds intersect faults at or near the basement/cover interface, and diverge from faults upsection; (2) fold hinges are narrow and interlimb angles cluster around 80--100[degree] regardless of fold location; (3) fold shape is typically angular, despite published cross sections that show concentric folds; and, (4) beds within the folds show thickening and/or thinning, most commonly adjacent to fold hinges. The rolling hinge model requires that rocks in the fold forelimbs bend through narrow fold hinges as deformation progressed. Examination of massive, competent rock units such as the Ord. Bighorn Dolomite, Miss. Madison Limestone, and, Penn. Tensleep Sandstone reveals no evidence of the extensive internal deformation that would be expected if hinges rolled through rocks of the forelimb. The hinges of some folds (e.g. Golf Creek anticline, Bighorn Mountains) are offset by secondary faults, effectively preventing the passage of rocks from backlimb to forelimb. The fixed hinge model proposes that the fold hinges were defined early in fold evolution, and beds were progressively rotated and steepened as the structure grew.

  11. Communicating climate change: alerting versus stimulating action, a few "philosophical" interrogations from a marine biogeochemist

    NASA Astrophysics Data System (ADS)

    Ragueneau, O.

    2009-04-01

    I'm a marine biogeochemist, working on diatoms and their role in the oceanic biological pump and climate. Since a few years, I'm placing a lot of time and energy in communicating science about climate change because I feel that, in addition to the remarkable work performed by the IPCC which has major implications on the political agenda, we also need to talk to each citizen to stimulate action towards mitigation. While doing so, many questions arise and I think it is very important that we share our experiences, so that each of us can continue the best he can. First, I try to experience different forms of communication. Science cafés, conferences, seminars with a group of adults to explore scientific controversies (e.g. carbon compensation, biofuels…), work with teachers to bring climate change in classes. My objectives are double: convey the most recent scientific information on climate change and stimulate action. And here arises the first question: what is the frontier between outreach and a more "political" engagement? Is there any difference between working with professionals towards integrated coastal zone management, and talking to citizens, which is an important scale, when addressing climate change? During these interventions, I have realized the need to communicate about "numbers". Global numbers, in terms of gigatons emitted by human activities. But also individual numbers, to address questions such as: how important are personal emissions compared to the industry for example? And what about my own emissions? Compared to those of my neighbour… The mean individual emissions in France compared to England or Germany. In Europe compared to the US or Africa… And if I want to do something, should I act on my transport, the energy I use at home, my food? In fact, do I even know there is CO2 in my plate? To help answering some of these questions, I have developed a calculator of personal CO2 emissions, that I use in a "conference-workshop" where people

  12. Mars rover mechanisms designed for Rocky 4

    NASA Technical Reports Server (NTRS)

    Rivellini, Tommaso P.

    1993-01-01

    A Mars rover prototype vehicle named Rocky 4 was designed and built at JPL during the fall of 1991 and spring 1992. This vehicle is the fourth in a series of rovers designed to test vehicle mobility and navigation software. Rocky 4 was the first attempt to design a vehicle with 'flight like' mass and functionality. It was consequently necessary to develop highly efficient mechanisms and structures to meet the vehicles very tight mass limit of 3 Kg for the entire mobility system (7 Kg for the full system). This paper will discuss the key mechanisms developed for the rover's innovative drive and suspension system. These are the wheel drive and strut assembly, the rocker-bogie suspension mechanism and the differential pivot. The end-to-end design, analysis, fabrication and testing of these components will also be discussed as will their performance during field testing. The lessons learned from Rocky 4 are already proving invaluable for the design of Rocky 6. Rocky 6 is currently being designed to fly on NASA's MESUR mission to Mars scheduled to launch in 1996.

  13. Complex coupled metabolic and prokaryotic community responses to increasing temperatures in anaerobic marine sediments: critical temperatures and substrate changes

    PubMed Central

    Roussel, Erwan G.; Cragg, Barry A.; Webster, Gordon; Sass, Henrik; Tang, Xiaohong; Williams, Angharad S.; Gorra, Roberta; Weightman, Andrew J.; Parkes, R. John

    2015-01-01

    The impact of temperature (0–80°C) on anaerobic biogeochemical processes and prokaryotic communities in marine sediments (tidal flat) was investigated in slurries for up to 100 days. Temperature had a non-linear effect on biogeochemistry and prokaryotes with rapid changes over small temperature intervals. Some activities (e.g. methanogenesis) had multiple ‘windows’ within a large temperature range (∼10 to 80°C). Others, including acetate oxidation, had maximum activities within a temperature zone, which varied with electron acceptor [metal oxide (up to ∼34°C) and sulphate (up to ∼50°C)]. Substrates for sulphate reduction changed from predominantly acetate below, and H2 above, a 43°C critical temperature, along with changes in activation energies and types of sulphate-reducing Bacteria. Above ∼43°C, methylamine metabolism ceased with changes in methanogen types and increased acetate concentrations (>1 mM). Abundances of uncultured Archaea, characteristic of deep marine sediments (e.g. MBGD Euryarchaeota, ‘Bathyarchaeota’) changed, indicating their possible metabolic activity and temperature range. Bacterial cell numbers were consistently higher than archaeal cells and both decreased above ∼15°C. Substrate addition stimulated activities, widened some activity temperature ranges (methanogenesis) and increased bacterial (×10) more than archaeal cell numbers. Hence, additional organic matter input from climate-related eutrophication may amplify the impact of temperature increases on sedimentary biogeochemistry. PMID:26207045

  14. Complex coupled metabolic and prokaryotic community responses to increasing temperatures in anaerobic marine sediments: critical temperatures and substrate changes.

    PubMed

    Roussel, Erwan G; Cragg, Barry A; Webster, Gordon; Sass, Henrik; Tang, Xiaohong; Williams, Angharad S; Gorra, Roberta; Weightman, Andrew J; Parkes, R John

    2015-08-01

    The impact of temperature (0-80°C) on anaerobic biogeochemical processes and prokaryotic communities in marine sediments (tidal flat) was investigated in slurries for up to 100 days. Temperature had a non-linear effect on biogeochemistry and prokaryotes with rapid changes over small temperature intervals. Some activities (e.g. methanogenesis) had multiple 'windows' within a large temperature range (∼10 to 80°C). Others, including acetate oxidation, had maximum activities within a temperature zone, which varied with electron acceptor [metal oxide (up to ∼34°C) and sulphate (up to ∼50°C)]. Substrates for sulphate reduction changed from predominantly acetate below, and H2 above, a 43°C critical temperature, along with changes in activation energies and types of sulphate-reducing Bacteria. Above ∼43°C, methylamine metabolism ceased with changes in methanogen types and increased acetate concentrations (>1 mM). Abundances of uncultured Archaea, characteristic of deep marine sediments (e.g. MBGD Euryarchaeota, 'Bathyarchaeota') changed, indicating their possible metabolic activity and temperature range. Bacterial cell numbers were consistently higher than archaeal cells and both decreased above ∼15°C. Substrate addition stimulated activities, widened some activity temperature ranges (methanogenesis) and increased bacterial (×10) more than archaeal cell numbers. Hence, additional organic matter input from climate-related eutrophication may amplify the impact of temperature increases on sedimentary biogeochemistry.

  15. Highly Diverse, Poorly Studied and Uniquely Threatened by Climate Change: An Assessment of Marine Biodiversity on South Georgia's Continental Shelf

    PubMed Central

    Hogg, Oliver T.; Barnes, David K. A.; Griffiths, Huw J.

    2011-01-01

    We attempt to quantify how significant the polar archipelago of South Georgia is as a source of regional and global marine biodiversity. We evaluate numbers of rare, endemic and range-edge species and how the faunal structure of South Georgia may respond to some of the fastest warming waters on the planet. Biodiversity data was collated from a comprehensive review of reports, papers and databases, collectively representing over 125 years of polar exploration. Classification of each specimen was recorded to species level and fully geo-referenced by depth, latitude and longitude. This information was integrated with physical data layers (e.g. temperature, salinity and flow) providing a visualisation of South Georgia's biogeography across spatial, temporal and taxonomic scales, placing it in the wider context of the Southern Hemisphere. This study marks the first attempt to map the biogeography of an archipelago south of the Polar Front. Through it we identify the South Georgian shelf as the most speciose region of the Southern Ocean recorded to date. Marine biodiversity was recorded as rich across taxonomic levels with 17,732 records yielding 1,445 species from 436 families, 51 classes and 22 phyla. Most species recorded were rare, with 35% recorded only once and 86% recorded <10 times. Its marine fauna is marked by the cumulative dominance of endemic and range-edge species, potentially at their thermal tolerance limits. Consequently, our data suggests the ecological implications of environmental change to the South Georgian marine ecosystem could be severe. If sea temperatures continue to rise, we suggest that changes will include depth profile shifts of some fauna towards cooler Antarctic Winter Water (90–150 m), the loss of some range-edge species from regional waters, and the wholesale extinction at a global scale of some of South Georgia's endemic species. PMID:21647236

  16. Trajectories and magnitude of change in coral reef fish populations in Philippine marine reserves: a meta-analysis

    NASA Astrophysics Data System (ADS)

    Maliao, R. J.; White, A. T.; Maypa, A. P.; Turingan, R. G.

    2009-12-01

    Marine reserves are widely implemented worldwide to meet both conservation and fisheries management goals. This study examines the efficacy of Philippine marine reserves using meta-analysis by comparing variations in fish density (1) between reserves and adjacent fished reefs (spatial comparison), (2) within reserves before establishment relative to years following the establishment (temporal comparison), and (3) among reserves classified based on size, age, and enforcement capacity. A grand (total) mean of nineteen 22.3 ha coral reef reserves, protected for a mean duration of 8.2 years, were included in the meta-analyses. The overall density of fishes was higher in the reserves compared with the fished reefs and this difference was largely accounted for by exploited fishes. However, the overall density of fishes within the same reserves remained similar from the period before its establishment to several years following its establishment. Only the density of nonexploited fishes increased significantly during years subsequent to the establishment of the reserves. Neither age nor size of reserves correlated with pattern of change in fish density following the establishment of the reserves; however, fish density was consistently higher in larger and older reserves relative to smaller and younger reserves in the spatial comparison. Furthermore, well-enforced reserves had higher density of exploited fishes relative to less-enforced reserves in both spatial and temporal comparisons. In general, the magnitude and trajectory of change in fish density following the establishment of Philippine marine reserves are influenced by (1) functional groups of fishes under consideration, (2) size and age of the reserve, and (3) level of enforcement of the regulatory mechanisms necessary to sustain a marine reserve.

  17. Highly diverse, poorly studied and uniquely threatened by climate change: an assessment of marine biodiversity on South Georgia's continental shelf.

    PubMed

    Hogg, Oliver T; Barnes, David K A; Griffiths, Huw J

    2011-01-01

    We attempt to quantify how significant the polar archipelago of South Georgia is as a source of regional and global marine biodiversity. We evaluate numbers of rare, endemic and range-edge species and how the faunal structure of South Georgia may respond to some of the fastest warming waters on the planet. Biodiversity data was collated from a comprehensive review of reports, papers and databases, collectively representing over 125 years of polar exploration. Classification of each specimen was recorded to species level and fully geo-referenced by depth, latitude and longitude. This information was integrated with physical data layers (e.g. temperature, salinity and flow) providing a visualisation of South Georgia's biogeography across spatial, temporal and taxonomic scales, placing it in the wider context of the Southern Hemisphere. This study marks the first attempt to map the biogeography of an archipelago south of the Polar Front. Through it we identify the South Georgian shelf as the most speciose region of the Southern Ocean recorded to date. Marine biodiversity was recorded as rich across taxonomic levels with 17,732 records yielding 1,445 species from 436 families, 51 classes and 22 phyla. Most species recorded were rare, with 35% recorded only once and 86% recorded <10 times. Its marine fauna is marked by the cumulative dominance of endemic and range-edge species, potentially at their thermal tolerance limits. Consequently, our data suggests the ecological implications of environmental change to the South Georgian marine ecosystem could be severe. If sea temperatures continue to rise, we suggest that changes will include depth profile shifts of some fauna towards cooler Antarctic Winter Water (90-150 m), the loss of some range-edge species from regional waters, and the wholesale extinction at a global scale of some of South Georgia's endemic species.

  18. A case of Rocky Mountain spotted fever.

    PubMed

    Rubel, Barry S

    2007-01-01

    Rocky Mountain spotted fever is a serious, generalized infection that is spread to humans through the bite of infected ticks. It can be lethal but it is curable. The disease gets its name from the Rocky Mountain region where it was first identified in 1896. The fever is caused by the bacterium Rickettsia rickettsii and is maintained in nature in a complex life cycle involving ticks and mammals. Humans are considered to be accidental hosts and are not involved in the natural transmission cycle of this pathogen. The author examined a 47-year-old woman during a periodic recall appointment. The patient had no dental problems other than the need for routine prophylaxis but mentioned a recent problem with swelling of her extremities with an accompanying rash and general malaise and soreness in her neck region. Tests were conducted and a diagnosis of Rocky Mountain spotted fever was made.

  19. Demonstrating the Effects of Ocean Acidification on Marine Organisms to Support Climate Change Understanding

    ERIC Educational Resources Information Center

    Kelley, Amanda L.; Hanson, Paul R.; Kelley, Stephanie A.

    2015-01-01

    Ocean acidification, a product of CO[subscript 2] absorption by the world's oceans, is largely driven by the anthropogenic combustion of fossil fuels and has already lowered the pH of marine ecosystems. Organisms with calcium carbonate shells and skeletons are especially susceptible to increasing environmental acidity due to reduction in the…

  20. The rate of removal and the compositional changes of diesel in Antarctic marine sediment.

    PubMed

    Woolfenden, E N M; Hince, G; Powell, S M; Stark, S C; Snape, I; Stark, J S; George, S C

    2011-12-01

    Diesels and lubricants used at research stations can persist in terrestrial and marine sediments for decades, but knowledge of their effects on the surrounding environments is limited. In a 5 year in situ investigation, marine sediment spiked with Special Antarctic Blend (SAB) diesel was placed on the seabed of O'Brien Bay near Casey Station, Antarctica and sampled after 5, 56, 65, 104 and 260 weeks. The rates and possible mechanisms of removal of the diesel from the marine sediments are presented here. The hydrocarbons within the spiked sediment were removed at an overall rate of 4.7mg total petroleum hydrocarbons kg(-1) sediment week(-1), or 245mgkg(-1)year(-1), although seasonal variation was evident. The concentration of total petroleum hydrocarbons fell markedly from 2020±340mgkg(-1) to 800±190mgkg(-1), but after 5 years the spiked sediment was still contaminated relative to natural organic matter (160±170mgkg(-1)). Specific compounds in SAB diesel preferentially decreased in concentration, but not as would be expected if biodegradation was the sole mechanism responsible. Naphthalene was removed more readily than n-alkanes, suggesting that aqueous dissolution played a major role in the reduction of SAB diesel. 1,3,5,7-Teramethyladamantane and 1,3-dimethyladamantane were the most recalcitrant isomers in the spiked marine sediment. Dissolution of aromatic compounds from marine sediment increases the availability of more soluble, aromatic compounds in the water column. This could increase the area of contamination and potentially broaden the region impacted by ecotoxicological effects from shallow sediment dwelling fauna, as noted during biodegradation, to shallow (<19m) water dwelling fauna.

  1. [Modulating marine ecosystem by marine viruses--a review].

    PubMed

    Wang, Hui; Bai, Shijie; Cai, Wenwei; Zheng, Tianling

    2009-05-01

    Marine viruses play great roles in the marine ecological system such as modulating the biodiversity and species population, regulating the nutrient cycling, intervening gene transfer and influencing climate changes. Recent research achievements on marine viruses were reviewed in this paper. We focused on the modulating role of marine viruses in marine ecosystem and discussed future research perspectives.

  2. Downwind changes in grain size of aeolian dust; examples from marine and terrestrial archives

    NASA Astrophysics Data System (ADS)

    Stuut, Jan-Berend; Prins, Maarten

    2013-04-01

    Aeolian dust in the atmosphere may have a cooling effect when small particles in the high atmosphere block incoming solar energy (e.g., Claquin et al., 2003) but it may also act as a 'greenhouse gas' when larger particles in the lower atmosphere trap energy that was reflected from the Earth's surface (e.g., Otto et al., 2007). Therefore, it is of vital importance to have a good understanding of the particle-size distribution of aeolian dust in space and time. As wind is a very size-selective transport mechanism, the sediments it carries typically have a very-well sorted grain-size distribution, which gradually fines from proximal to distal deposition sites. This fact has been used in numerous paleo-environmental studies to both determine source-to-sink changes in the particle size of aeolian dust (e.g., Weltje and Prins, 2003; Holz et al., 2004; Prins and Vriend, 2007) and to quantify mass-accumulation rates of aeolian dust (e.g., Prins and Weltje 1999; Stuut et al., 2002; Prins et al., 2007; Prins and Vriend, 2007; Stuut et al., 2007; Tjallingii et al., 2008; Prins et al., 2009). Studies on modern wind-blown particles have demonstrated that particle size of dust not only is a function of lateral but also vertical transport distance (e.g., Torres-Padron et al., 2002; Stuut et al., 2005). Nonetheless, there are still many unresolved questions related to the physical properties of wind-blown particles like e.g., the case of "giant" quartz particles found on Hawaii (Betzer et al., 1988) that can only originate from Asia but have a too large size for the distance they travelled through the atmosphere. Here, we present examples of dust particle-size distributions from terrestrial (loess) as well as marine (deep-sea sediments) sedimentary archives and their spatial and temporal changes. With this contribution we hope to provide quantitative data for the modelling community in order to get a better grip on the role of wind-blown particles in the climate system. Cited

  3. 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.

  4. Climate change. Six centuries of variability and extremes in a coupled marine-terrestrial ecosystem.

    PubMed

    Black, Bryan A; Sydeman, William J; Frank, David C; Griffin, Daniel; Stahle, David W; García-Reyes, Marisol; Rykaczewski, Ryan R; Bograd, Steven J; Peterson, William T

    2014-09-19

    Reported trends in the mean and variability of coastal upwelling in eastern boundary currents have raised concerns about the future of these highly productive and biodiverse marine ecosystems. However, the instrumental records on which these estimates are based are insufficiently long to determine whether such trends exceed preindustrial limits. In the California Current, a 576-year reconstruction of climate variables associated with winter upwelling indicates that variability increased over the latter 20th century to levels equaled only twice during the past 600 years. This modern trend in variance may be unique, because it appears to be driven by an unprecedented succession of extreme, downwelling-favorable, winter climate conditions that profoundly reduce productivity for marine predators of commercial and conservation interest.

  5. The Effect of Changes in Polar Sea Ice on Emissions of Marine Aerosols

    NASA Astrophysics Data System (ADS)

    Matrai, P.; Gabric, A. J.

    2015-12-01

    Cloud radiative effects remain a major weakness in our understanding of the climate system and consequently in developing accurate climate projections. This is mainly true for Arctic low-level clouds in their key role of regulating surface energy fluxes which affect the freezing and melting of sea ice. The radiative properties of clouds are strongly dependent on the number concentration of airborne water-soluble particles, known as cloud condensation nuclei (CCN). In the Arctic, the aerosol-cloud-radiation relationship is more complex than elsewhere and the clouds constitute a warming factor for climate, rather than cooling, most of the year. This is due to the semi-permanent ice cover, which raises the albedo of the surface, and the clean Arctic air, which decreases the albedo of the clouds. There has been much discussion on the relative magnitude of the biogenic source of polar CCN: Primary organic marine aerosols and/or sulfate-containing aerosols, derived from marine emissions. Regional field measurements and pan- (Ant)Arctic model simulations don't necessarily agree. Arctic CCN are formed primarily by aggregates of marine organic material and may grow in mass by condensation. Southern Ocean aerosols may be dominated by sulfate particles and organic particles at lower and higher Antarctic latitudes, respectively. The interaction of polar marine microorganisms, seasonality, sea ice cover, presence or absence of sea spray, and atmospheric heterogeneous processes combine to control natural aerosol concentrations and mass, thus modulating the sensitivity of cloud properties, including their reflectivity and the resulting regional radiation budget. We discuss Arctic and Antarctic field and satellite observations and establish a strong and fundamental link between the biology at the ocean/sea ice interface, clouds and climate over polar regions.

  6. Habitat partitioning by five congeneric and abundant Choerodon species (Labridae) in a large subtropical marine embayment

    NASA Astrophysics Data System (ADS)

    Fairclough, D. V.; Clarke, K. R.; Valesini, F. J.; Potter, I. C.

    2008-04-01

    The habitats occupied by the juveniles and adults of five morphologically similar, diurnally active and abundant Choerodon species in the large subtropical environment of Shark Bay, a "World Heritage Property" on the west coast of Australia, have been determined. The densities of the two life cycle stages of each Choerodon species in those habitats were used in various analyses to test the hypotheses that: (1) habitats are partitioned among these species and between their juveniles and adults; (2) such habitat partitioning is greatest in the case of the two Western Australian endemic species, i.e. Choerodon rubescens and Choerodon cauteroma; and (3) the extent of habitat partitioning between both of these two species and the only species that is widely distributed in the Indo-West Pacific, i.e. Choerodon schoenleinii, will be less pronounced. Initially, catches of each of the five congeneric species, obtained during other studies in Shark Bay by angling, spearfishing and otter trawling, were collated to elucidate the broad distribution of these species in that embayment. Underwater visual census was then used to determine the densities of the juveniles and adults of each Choerodon species at sites representing the four habitat types in which one or more of these species had been caught, i.e. reefs in marine waters at the western boundary of the bay and seagrass, reefs and rocky shorelines in the two inner gulfs. The compositions of the Choerodon species over marine (entrance channel) reefs and in seagrass were significantly different and each differed significantly from those in both inner gulf reefs and rocky shorelines, which were, however, not significantly different. Choerodon rubescens was restricted to exposed marine reefs, and thus occupied a different habitat and location of the bay than C. cauteroma, the other endemic species, which was almost exclusively confined to habitats found in the inner gulfs. Choerodon cauteroma differed from other Choerodon

  7. Global change ecotoxicology: Identification of early life history bottlenecks in marine invertebrates, variable species responses and variable experimental approaches.

    PubMed

    Byrne, M

    2012-05-01

    Climate change is a threat to marine biota because increased atmospheric CO₂ is causing ocean warming, acidification, hypercapnia and decreased carbonate saturation. These stressors have toxic effects on invertebrate development. The persistence and success of populations requires all ontogenetic stages be completed successfully and, due to their sensitivity to environmental stressors, developmental stages may be a population bottleneck in a changing ocean. Global change ecotoxicology is being used to identify the marine invertebrate developmental stages vulnerable to climate change. This overview of research, and the methodologies used, shows that most studies focus on acidification, with few studies on ocean warming, despite a long history of research on developmental thermotolerance. The interactive effects of stressors are poorly studied. Experimental approaches differ among studies. Fertilization in many species exhibits a broad tolerance to warming and/or acidification, although different methodologies confound inter-study comparisons. Early development is susceptible to warming and most calcifying larvae are sensitive to acidification/increased pCO₂. In multistressor studies moderate warming diminishes the negative impact of acidification on calcification in some species. Development of non-calcifying larvae appears resilient to near-future ocean change. Although differences in species sensitivities to ocean change stressors undoubtedly reflect different tolerance levels, inconsistent handling of gametes, embryos and larvae probably influences different research outcomes. Due to the integrative 'developmental domino effect', life history responses will be influenced by the ontogenetic stage at which experimental incubations are initiated. Exposure to climate change stressors from early development (fertilization where possible) in multistressor experiments is needed to identify ontogenetic sensitivities and this will be facilitated by more consistent

  8. Rocky Mountain Spotted Fever in Argentina

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We describe the first molecular confirmation of Rickettsia rickettsii, the cause of Rocky Mountain spotted fever (RMSF), from a tick vector, Amblyomma cajennense, and from a cluster of fatal spotted fever cases in Argentina. Questing A. cajennense ticks were collected at or near sites of presumed or...

  9. Rocky Mountain spotted fever in Argentina

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cases of epidemic typhus have been documented in Argentina since 1919; however, no confirmed reports of spotted fever rickettsiosis were described in this country until 1999. We describe the first molecular confirmation of Rickettsia rickettsii, the etiologic agent of Rocky Mountain spotted fever (R...

  10. Rocky Mountain spotted fever in dogs, Brazil.

    PubMed

    Labruna, Marcelo B; Kamakura, Orson; Moraes-Filho, Jonas; Horta, Mauricio C; Pacheco, Richard C

    2009-03-01

    Clinical illness caused by Rickettsia rickettsii in dogs has been reported solely in the United States. We report 2 natural clinical cases of Rocky Mountain spotted fever in dogs in Brazil. Each case was confirmed by seroconversion and molecular analysis and resolved after doxycycline therapy.

  11. Late glacial aridity in southern Rocky Mountains

    SciTech Connect

    Davis, O.K.; Pitblado, B.L.

    1995-09-01

    While the slopes of the present-day Colorado Rocky Mountains are characterized by large stands of subalpine and montane conifers, the Rockies of the late glacial looked dramatically different. Specifically, pollen records suggest that during the late glacial, Artemisia and Gramineae predominated throughout the mountains of Colorado. At some point between 11,000 and 10,000 B.P., however, both Artemisia and grasses underwent a dramatic decline, which can be identified in virtually every pollen diagram produced for Colorado mountain sites, including Como Lake (Sangre de Cristo Mountains), Copley Lake and Splains; Gulch (near Crested Butte), Molas Lake (San Juan Mountains), and Redrock Lake (Boulder County). Moreover, the same pattern seems to hold for pollen spectra derived for areas adjacent to Colorado, including at sites in the Chuska Mountains of New Mexico and in eastern Wyoming. The implications of this consistent finding are compelling. The closest modem analogues to the Artemisia- and Gramineae-dominated late-glacial Colorado Rockies are found in the relatively arid northern Great Basin, which suggests that annual precipitation was much lower in the late-glacial southern Rocky Mountains than it was throughout the Holocene.

  12. Field Trip to a Rocky Shore.

    ERIC Educational Resources Information Center

    Maine Univ., Orono. Cooperative Extension Service.

    Field trip activities designed for use on Maine's coast are provided, with brief definitions of the major physical zones to be found in this area. An introduction to the study of zonation of plants and animals living on the rocky shore is presented along with a list of the materials needed and the procedures to be followed when making a study of…

  13. Geology highlights for Ride the Rockies 2010

    USGS Publications Warehouse

    Slate, J.L.; Hess, Amber; Van Sistine, D.R.

    2010-01-01

    The author provides a brief description of the geology along the route for each day of the ride, from June 13 through June 19, 2010. Ride the Rockies begins in Grand Junction, with stops in Delta, Ouray, Durango, Pagosa Springs, Alamosa, and ends in Salida, Colorado. A small, generalized geologic map also is shown.

  14. Geology Highlights for Ride the Rockies 2009

    USGS Publications Warehouse

    Slate, Janet

    2009-01-01

    The author provides a brief description of the geology along the route for each day of the ride, from June 14 through June 19, 2009. Ride the Rockies begins and ends in Glenwood Springs, with stops in Hotchkiss, Gunnison, Salida, Leadville, Aspen, and back to Glenwood Springs, Colorado. A small, generalized geologic map also is shown.

  15. Geology highlights, Ride the Rockies 2011

    USGS Publications Warehouse

    Slate, Janet L.

    2011-01-01

    The author provides a brief description of the geology along the route for each day of the ride, from June 12 through June 17, 2011. Ride the Rockies begins in Crested Butte, Colorado, with stops in Buena Vista, Edwards, Steamboat Springs, Granby, and Georgetown. A small, generalized geologic map also is shown.

  16. Paratuberculosis (Johne's disease) in bighorn sheep and a Rocky Mountain goat in Colorado.

    PubMed

    Williams, E S; Spraker, T R; Schoonveld, G G

    1979-04-01

    Between May, 1972 and February, 1978, six cases of paratuberculosis (Johne's Disease) caused by Mycobacterium paratuberculosis were diagnosed in free-ranging Rocky Mountain bighorn sheep (Ovis canadensis) and one Rocky Mountain goat (Oreamnos americanus) on or near Mt. Evans in Colorado. Diagnosis of paratuberculosis was based on gross and histopathologic examination of the animals and by isolation of M. paratuberculosis from three sheep and the goat. The clinical signs and pathologic changes seen in the bighorn sheep resembled those described in cattle, while the lesions in the goat were similar to those described for domestic sheep and goats.

  17. Assessing Fishing and Marine Biodiversity Changes Using Fishers' Perceptions: The Spanish Mediterranean and Gulf of Cadiz Case Study

    PubMed Central

    Coll, Marta; Carreras, Marta; Ciércoles, Cristina; Cornax, Maria-José; Gorelli, Giulia; Morote, Elvira; Sáez, Raquel

    2014-01-01

    Background The expansion of fishing activities has intensively transformed marine ecosystems worldwide. However, available time series do not frequently cover historical periods. Methodology Fishers' perceptions were used to complement data and characterise changes in fishing activity and exploited ecosystems in the Spanish Mediterranean Sea and Gulf of Cadiz. Fishers' interviews were conducted in 27 fishing harbours of the area, and included 64 fishers from ages between 20 to >70 years old to capture the experiences and memories of various generations. Results are discussed in comparison with available independent information using stock assessments and international convention lists. Principal Findings According to fishers, fishing activity substantially evolved in the area with time, expanding towards deeper grounds and towards areas more distant from the coast. The maximum amount of catch ever caught and the weight of the largest species ever captured inversely declined with time. Fishers (70%) cited specific fishing grounds where depletion occurred. They documented ecological changes of marine biodiversity during the last half of the century: 94% reported the decline of commercially important fish and invertebrates and 61% listed species that could have been extirpated, with frequent mentions to cartilaginous fish. Declines and extirpations were in line with available quantitative evaluations from stock assessments and international conventions, and were likely linked to fishing impacts. Conversely, half of interviewed fishers claimed that several species had proliferated, such as cephalopods, jellyfish, and small-sized fish. These changes were likely related to trophic cascades due to fishing and due to climate change effects. The species composition of depletions, local extinctions and proliferations showed differences by region suggesting that regional dynamics are important when analysing biodiversity changes. Conclusions/Significance Using fishers

  18. Presentation of the FMI 5000 Project: Environmental changes: Fluvio-marine interactions over the last 5000yrs

    NASA Astrophysics Data System (ADS)

    Ramos-Pereira, Ana; Ramos, Catarina; Trindade, Jorge; Araújo-Gomes, João.; Rocha, Jorge; Granja, Helena; Gonçalves, Luís.; Monge-Soares, António; Martins, José

    2010-05-01

    Keywords: Estuaries, Environmental Changes, Holocene, GIS Modelling, Portugal FMI 5000 Project (between 2010 and 2012) aims to evaluate, in different estuarine environmental conditions, the balance between fluvial and marine influences, the responses to climatic events and the impact of land use changes. The temporal window chosen, contains different trends of the sea level, climatic fluctuations like the Bond events or humid episodes recorded in the Iberian Peninsula, as well as the increase of the human intervention in the landscape, particularly sensitive since the Bronze Age (circa 3500yr), imprinted in the filling-up of the alluvial plain estuaries. The Portuguese mainland mesotidal coast spreads out in two different environmental conditions: (i) the West coast exposed to the NW dominant waves, with a temperate oceanic climate and fluvial regimes and (ii) the Southern sheltered one, but open to the SW storms, with a Mediterranean climate and with occasional heavy fluvial discharges. This contrast along the coast creates a good field of research to achieve the aims of the project. To prosecute this goal, estuaries of medium drainage basins were selected as they have homogeneous climate, geologic and geomorphologic conditions, allowing to define accurately the hydroclimatic events that contribute to the infilling of the estuarine plains. The small changes are recorded not only in the textural properties of the sediments, already recognized in the sediments of the Tagus and Guadiana rivers and in the small estuaries of the Spanish southern coast but also in the micro fauna, pollens and non-pollen-palinomorphs allowing to define the environmental changes, both marine and fluvial. To achieve the Project goals we select three estuaries in different climatic and wave climate conditions, to develop four different kinds of research and methodologies: (i) To identify millenary evolution, several hand-operated gauge auger cores or vibracores will be carried out in the

  19. A Long, Winding (and Rocky) Road to Environmental Education for Sustainability in 2006

    ERIC Educational Resources Information Center

    Gough, Annette

    2006-01-01

    This article charts the history of environmental education over four decades--from the 1960s to 2006--as a rocky road of determined chocolate with the possibilities of rocks (nuts) and easy passage (marshmallow). There were distractions such as suggestions of changing names and new directions (add fruit?) along the way but the road has continued…

  20. Geographic patterns of genetic variation and population structure in Pinus aristata, Rocky Mountain bristlecone pine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pinus aristata Engelm., Rocky Mountain bristlecone pine, has a narrow core geographic and elevational distribution, occurs in disjunct populations and is threatened by multiple stresses, including rapid climate change, white pine blister rust, and bark beetles. Knowledge of genetic diversity and pop...

  1. A Regional Atmospheric Continuous CO2 Network In The Rocky Mountains (Rocky RACCOON)

    NASA Astrophysics Data System (ADS)

    Stephens, B.; de Wekker, S.; Watt, A.; Schimel, D.

    2005-12-01

    We have established a continuous CO2 observing network in the Rocky Mountains, building on technological and modeling advances made during the Carbon in the Mountains Experiment (CME), to improve our understanding of regional carbon fluxes and to fill key gaps in the North American Carbon Program (NACP). We will present a description of the Rocky RACCOON network and early results from the first three sites. There are strong scientific and societal motivations for determining CO2 exchanges on regional scales. NACP aims to address these concerns through a dramatic expansion in observations and modeling capabilities over North America. Mountain forests in particular represent a significant potential net CO2 sink in the U.S. and are highly sensitive to land-use practices and climate change. However, plans for new continuous CO2 observing sites have omitted the mountain west. This resulted from expensive instrumentation in the face of limited resources, and a perception that current atmospheric transport models are not sophisticated enough to interpret CO2 measurements made in complex terrain. Through our efforts in CME, we have a new autonomous, inexpensive, and robust CO2 analysis system and are developing mountain CO2 modeling tools that will help us to overcome these obstacles. Preliminary observational and modeling results give us confidence that continuous CO2 observations from mountain top observatories will provide useful constraints on regional carbon cycling and will be valuable in the continental inverse modeling efforts planned for NACP. We began at three Colorado sites in August 2005 and hope to add three to six sites in other western states in subsequent years, utilizing existing observatories to the maximum extent possible. The first three sites are at Niwot Ridge, allowing us to have an ongoing intercomparison with flask measurements made by NOAA CMDL; at Storm Peak Laboratory near Steamboat Springs, allowing us to investigate comparisons between these

  2. Going with the flow: the role of ocean circulation in global marine ecosystems under a changing climate.

    PubMed

    van Gennip, Simon J; Popova, Ekaterina E; Yool, Andrew; Pecl, Gretta T; Hobday, Alistair J; Sorte, Cascade J B

    2016-12-09

    Ocean warming, acidification, deoxygenation and reduced productivity are widely considered to be the major stressors to ocean ecosystems induced by emissions of CO2 . However, an overlooked stressor is the change in ocean circulation in response to climate change. Strong changes in the intensity and position of the western boundary currents have already been observed, and the consequences of such changes for ecosystems are beginning to emerge. In this study, we address climatically induced changes in ocean circulation on a global scale but relevant to propagule dispersal for species inhabiting global shelf ecosystems, using a high-resolution global ocean model run under the IPCC RCP 8.5 scenario. The ¼ degree model resolution allows improved regional realism of the ocean circulation beyond that of available CMIP5-class models. We use a Lagrangian approach forced by modelled ocean circulation to simulate the circulation pathways that disperse planktonic life stages. Based on trajectory backtracking, we identify present-day coastal retention, dominant flow and dispersal range for coastal regions at the global scale. Projecting into the future, we identify areas of the strongest projected circulation change and present regional examples with the most significant modifications in their dominant pathways. Climatically induced changes in ocean circulation should be considered as an additional stressor of marine ecosystems in a similar way to ocean warming or acidification.

  3. Heavy metal effects on cellular shape changes, cleavage, and larval development of the marine gastropod mollusk, (Ilyanassa obsoleta Say)

    SciTech Connect

    Conrad, G.W.

    1988-07-01

    The spawning areas for many marine invertebrates are in intertidal zones which can be exposed to surface water run-off containing heavy metals. The cellular shape changes and cleavage patterns of Ilyanassa embryos greatly resemble those of bivalve mollusks, such as Mytilus edulis, that occur in the same intertidal areas. Determining the concentrations of heavy metals tolerated by the molluscan embryos inhabiting such clam and mussel beds therefore is of some economic significance. Moreover, such research may providedata on the heavy metal effects on the cytoskeleton. There is increasing evidence that components of the cytoskeleton, directly or indirectly, are targets for toxic agents. Polar lobe formation is a cellular shape change that resembles cytokinesis. It is seen in the fertilized eggs of many marine mollusks. Recent data with inorganic and organic Ca/sup 2 +/ antagonists suggest that both polar lobe formation and cytokinesis utilize Ca/sup 2 +/ released from sequestered, intracellular sites. Both of these cellular constrictions are associated with microfilaments and are preceded by activation steps requiring microtubules. The data presented below suggest that several heavy metals affect the microfilament-dependent steps.

  4. Late Permian marine ecosystem collapse began in deeper waters: evidence from brachiopod diversity and body size changes.

    PubMed

    He, W-H; Shi, G R; Twitchett, R J; Zhang, Y; Zhang, K-X; Song, H-J; Yue, M-L; Wu, S-B; Wu, H-T; Yang, T-L; Xiao, Y-F

    2015-03-01

    Analysis of Permian-Triassic brachiopod diversity and body size changes from different water depths spanning the continental shelf to basinal facies in South China provides insights into the process of environmental deterioration. Comparison of the temporal changes of brachiopod diversity between deepwater and shallow-water facies demonstrates that deepwater brachiopods disappeared earlier than shallow-water brachiopods. This indicates that high environmental stress commenced first in deepwater settings and later extended to shallow waters. This environmental stress is attributed to major volcanic eruptions, which first led to formation of a stratified ocean and a chemocline in the outer shelf and deeper water environments, causing the disappearance of deep marine benthos including brachiopods. The chemocline then rapidly migrated upward and extended to shallow waters, causing widespread mass extinction of shallow marine benthos. We predict that the spatial and temporal patterns of earlier onset of disappearance/extinction and ecological crisis in deeper water ecosystems will be recorded during other episodes of rapid global warming.

  5. Sensitivity of Interannual Fluctuations of the Marine Ecoystem to Changes in the Ocean Circulation.

    NASA Astrophysics Data System (ADS)

    Winguth, A. M.; Maier-Reimer, E.; Dobbel, M.

    2002-12-01

    Factors controlling the interannual distribution of phytoplankton or zooplankton are largely unknown and thus resulting in large uncertainties in the prediction of sources and sinks of CO2 in the ocean. We are using two coupled ocean general circulation - marine ecosystem models with different resolution, the NPZD-type HAMOCC4 coupled to the LSG and the C-HOPE, to explore how different physical resolutions and parameterizations can explain some of the agreements and discrepancies between the data and the model. In addition, sensitivity experiments by variation of the ecosystem parameters and by including an empirical chlorophyll-to-carbon ratio have been carried out to study and discuss potential causes of the model-data differences between the observed and simulated chlorophyll concentrations. These sensitivity experiments are designed to be a first step towards a currently developed inverse ecosystem model to quantify large-scale interannual-to-decadal fluctuations of the marine carbon cycle and to provide more accurate predictions of the climate system.

  6. Responses of the marine diatom Thalassiosira pseudonana to changes in CO2 concentration: a proteomic approach

    PubMed Central

    Clement, Romain; Lignon, Sabrina; Mansuelle, Pascal; Jensen, Erik; Pophillat, Matthieu; Lebrun, Regine; Denis, Yann; Puppo, Carine; Maberly, Stephen C.; Gontero, Brigitte

    2017-01-01

    The concentration of CO2 in many aquatic systems is variable, often lower than the KM of the primary carboxylating enzyme Rubisco, and in order to photosynthesize efficiently, many algae operate a facultative CO2 concentrating mechanism (CCM). Here we measured the responses of a marine diatom, Thalassiosira pseudonana, to high and low concentrations of CO2 at the level of transcripts, proteins and enzyme activity. Low CO2 caused many metabolic pathways to be remodeled. Carbon acquisition enzymes, primarily carbonic anhydrase, stress, degradation and signaling proteins were more abundant while proteins associated with nitrogen metabolism, energy production and chaperones were less abundant. A protein with similarities to the Ca2+/ calmodulin dependent protein kinase II_association domain, having a chloroplast targeting sequence, was only present at low CO2. This protein might be a specific response to CO2 limitation since a previous study showed that other stresses caused its reduction. The protein sequence was found in other marine diatoms and may play an important role in their response to low CO2 concentration. PMID:28181560

  7. Landslide-dammed paleolake perturbs marine sedimentation and drives genetic change in anadromous fish

    PubMed Central

    Mackey, Benjamin H.; Roering, Joshua J.; Lamb, Michael P.

    2011-01-01

    Large bedrock landslides have been shown to modulate rates and processes of river activity by forming dams, forcing upstream aggradation of water and sediment, and generating catastrophic outburst floods. Less apparent is the effect of large landslide dams on river ecosystems and marine sedimentation. Combining analyses of 1-m resolution topographic data (acquired via airborne laser mapping) and field investigation, we present evidence for a large, landslide-dammed paleolake along the Eel River, CA. The landslide mass initiated from a high-relief, resistant outcrop which failed catastrophically, blocking the Eel River with an approximately 130-m-tall dam. Support for the resulting 55-km-long, 1.3-km3 lake includes subtle shorelines cut into bounding terrain, deltas, and lacustrine sediments radiocarbon dated to 22.5 ka. The landslide provides an explanation for the recent genetic divergence of local anadromous (ocean-run) steelhead trout (Oncorhynchus mykiss) by blocking their migration route and causing gene flow between summer run and winter run reproductive ecotypes. Further, the dam arrested the prodigious flux of sediment down the Eel River; this cessation is recorded in marine sedimentary deposits as a 10-fold reduction in deposition rates of Eel-derived sediment and constitutes a rare example of a terrestrial event transmitted through the dispersal system and recorded offshore. PMID:22084068

  8. Decadal trends in marine reserves reveal differential rates of change in direct and indirect effects

    PubMed Central

    Babcock, R. C.; Shears, N. T.; Alcala, A. C.; Barrett, N. S.; Edgar, G. J.; Lafferty, K. D.; McClanahan, T. R.; Russ, G. R.

    2010-01-01

    Decadal-scale observations of marine reserves suggest that indirect effects on taxa that occur through cascading trophic interactions take longer to develop than direct effects on target species. Combining and analyzing a unique set of long-term time series of ecologic data in and out of fisheries closures from disparate regions, we found that the time to initial detection of direct effects on target species (±SE) was 5.13 ± 1.9 years, whereas initial detection of indirect effects on other taxa, which were often trait mediated, took significantly longer (13.1 ± 2.0 years). Most target species showed initial direct effects, but their trajectories over time were highly variable. Many target species continued to increase, some leveled off, and others decreased. Decreases were due to natural fluctuations, fishing impacts from outside reserves, or indirect effects from target species at higher trophic levels. The average duration of stable periods for direct effects was 6.2 ± 1.2 years, even in studies of more than 15 years. For indirect effects, stable periods averaged 9.1 ± 1.6 years, although this was not significantly different from direct effects. Populations of directly targeted species were more stable in reserves than in fished areas, suggesting increased ecologic resilience. This is an important benefit of marine reserves with respect to their function as a tool for conservation and restoration. PMID:20176941

  9. Changes in contaminant distributions with trophic level in a marine food chain study

    SciTech Connect

    Pruell, R.J.; Johnson, M.W.; Taplin, B.K.; McGovern, D.G.; Montmarquet, B.T.

    1994-12-31

    A laboratory study was designed to investigate the transfer of chlorinated organic contaminants from sediments to marine biota in a simplified marine food chain. Sediments collected from the Passaic River, NJ, which contained high concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), PCBs and chlorinated pesticides, were used as the contamination source. Polychaete worms (Nereis virens) were exposed to Passaic River sediment for 70 days to allow steady-state concentrations to be achieved and then these organisms were fed to a crustacean, the American lobster (Homarus americanus). Contaminant distributions were altered significantly as they passed from sediments to polychaetes and then to the lobster. PCDDs and PCDFs containing four or five chlorines were accumulated by the polychaetes and lobster; however, the highly chlorinated congeners were not accumulated. PCB patterns in lobsters indicated that these organisms metabolized many PCB congeners. Coplanar PCBs did not appear to be metabolized and therefore became enriched relative to total PCB levels in the lobsters. Lobsters also greatly altered the ratios of chlordane and DDT series compounds relative to those in the sediments and polychaetes.

  10. Landslide-dammed paleolake perturbs marine sedimentation and drives genetic change in anadromous fish.

    PubMed

    Mackey, Benjamin H; Roering, Joshua J; Lamb, Michael P

    2011-11-22

    Large bedrock landslides have been shown to modulate rates and processes of river activity by forming dams, forcing upstream aggradation of water and sediment, and generating catastrophic outburst floods. Less apparent is the effect of large landslide dams on river ecosystems and marine sedimentation. Combining analyses of 1-m resolution topographic data (acquired via airborne laser mapping) and field investigation, we present evidence for a large, landslide-dammed paleolake along the Eel River, CA. The landslide mass initiated from a high-relief, resistant outcrop which failed catastrophically, blocking the Eel River with an approximately 130-m-tall dam. Support for the resulting 55-km-long, 1.3-km(3) lake includes subtle shorelines cut into bounding terrain, deltas, and lacustrine sediments radiocarbon dated to 22.5 ka. The landslide provides an explanation for the recent genetic divergence of local anadromous (ocean-run) steelhead trout (Oncorhynchus mykiss) by blocking their migration route and causing gene flow between summer run and winter run reproductive ecotypes. Further, the dam arrested the prodigious flux of sediment down the Eel River; this cessation is recorded in marine sedimentary deposits as a 10-fold reduction in deposition rates of Eel-derived sediment and constitutes a rare example of a terrestrial event transmitted through the dispersal system and recorded offshore.

  11. Decadal trends in marine reserves reveal differential rates of change in direct and indirect effects

    USGS Publications Warehouse

    Babcock, R.C.; Shears, N.T.; Alcala, A.C.; Barrett, N.S.; Edgar, G.J.; Lafferty, K.D.; McClanahan, T.R.; Russ, G.R.

    2010-01-01

    Decadal-scale observations of marine reserves suggest that indirect effects on taxa that occur through cascading trophic interactions take longer to develop than direct effects on target species. Combining and analyzing a unique set of long-term time series of ecologic data in and out of fisheries closures from disparate regions, we found that the time to initial detection of direct effects on target species (+ or -SE) was 5.13 + or - 1.9 years, whereas initial detection of indirect effects on other taxa, which were often trait mediated, took significantly longer (13.1 + or - 2.0 years). Most target species showed initial direct effects, but their trajectories over time were highly variable. Many target species continued to increase, some leveled off, and others decreased. Decreases were due to natural fluctuations, fishing impacts from outside reserves, or indirect effects from target species at higher trophic levels. The average duration of stable periods for direct effects was 6.2 + or - 1.2 years, even in studies of more than 15 years. For indirect effects, stable periods averaged 9.1 + or - 1.6 years, although this was not significantly different from direct effects. Populations of directly targeted species were more stable in reserves than in fished areas, suggesting increased ecologic resilience. This is an important benefit of marine reserves with respect to their function as a tool for conservation and restoration.

  12. Strategy for mitigation of marine debris: analysis of sources and composition of marine debris in northern Taiwan.

    PubMed

    Kuo, Fan-Jun; Huang, Hsiang-Wen

    2014-06-15

    Six sites (two sites for each of rocky shores, sandy beaches, and fishing ports) in northern Taiwan were selected to investigate the amount and density of marine debris in each of the four seasons and after spring and neap tides from 2012 to 2013. The results indicate that marine debris was higher on rocky shores than sandy beaches and fishing ports. There is no significant difference between season and tide. The dominant debris was plastic-type, followed by polystyrene. The majority of debris originated from recreational activities, followed from ocean/waterway activities. The results suggest that the following actions are needed: (1) continue and reinforce the plastic-limit policy; (2) increase the cleaning frequency at rocky shores; (3) promote marine environmental education, with a goal of debris-free coasts; (4) recycle fishing gear and to turn that gear into energy; and (5) coordinate between agencies to establish a mechanism to monitor debris.

  13. Greenhouse-icehouse transition in the Late Ordovician marks a step change in extinction regime in the marine plankton

    NASA Astrophysics Data System (ADS)

    Crampton, James S.; Cooper, Roger A.; Sadler, Peter M.; Foote, Michael

    2016-02-01

    Two distinct regimes of extinction dynamic are present in the major marine zooplankton group, the graptolites, during the Ordovician and Silurian periods (486-418 Ma). In conditions of "background" extinction, which dominated in the Ordovician, taxonomic evolutionary rates were relatively low and the probability of extinction was highest among newly evolved species ("background extinction mode"). A sharp change in extinction regime in the Late Ordovician marked the onset of repeated severe spikes in the extinction rate curve; evolutionary turnover increased greatly in the Silurian, and the extinction mode changed to include extinction that was independent of species age ("high-extinction mode"). This change coincides with a change in global climate, from greenhouse to icehouse conditions. During the most extreme episode of extinction, the Late Ordovician Mass Extinction, old species were selectively removed ("mass extinction mode"). Our analysis indicates that selective regimes in the Paleozoic ocean plankton switched rapidly (generally in <0.5 My) from one mode to another in response to environmental change, even when restoration of the full ecosystem was much slower (several million years). The patterns observed are not a simple consequence of geographic range effects or of taxonomic changes from Ordovician to Silurian. Our results suggest that the dominant primary controls on extinction throughout the lifespan of this clade were abiotic (environmental), probably mediated by the microphytoplankton.

  14. Greenhouse-icehouse transition in the Late Ordovician marks a step change in extinction regime in the marine plankton.

    PubMed

    Crampton, James S; Cooper, Roger A; Sadler, Peter M; Foote, Michael

    2016-02-09

    Two distinct regimes of extinction dynamic are present in the major marine zooplankton group, the graptolites, during the Ordovician and Silurian periods (486-418 Ma). In conditions of "background" extinction, which dominated in the Ordovician, taxonomic evolutionary rates were relatively low and the probability of extinction was highest among newly evolved species ("background extinction mode"). A sharp change in extinction regime in the Late Ordovician marked the onset of repeated severe spikes in the extinction rate curve; evolutionary turnover increased greatly in the Silurian, and the extinction mode changed to include extinction that was independent of species age ("high-extinction mode"). This change coincides with a change in global climate, from greenhouse to icehouse conditions. During the most extreme episode of extinction, the Late Ordovician Mass Extinction, old species were selectively removed ("mass extinction mode"). Our analysis indicates that selective regimes in the Paleozoic ocean plankton switched rapidly (generally in <0.5 My) from one mode to another in response to environmental change, even when restoration of the full ecosystem was much slower (several million years). The patterns observed are not a simple consequence of geographic range effects or of taxonomic changes from Ordovician to Silurian. Our results suggest that the dominant primary controls on extinction throughout the lifespan of this clade were abiotic (environmental), probably mediated by the microphytoplankton.

  15. Greenhouse−icehouse transition in the Late Ordovician marks a step change in extinction regime in the marine plankton

    PubMed Central

    Crampton, James S.; Cooper, Roger A.; Sadler, Peter M.; Foote, Michael

    2016-01-01

    Two distinct regimes of extinction dynamic are present in the major marine zooplankton group, the graptolites, during the Ordovician and Silurian periods (486−418 Ma). In conditions of “background” extinction, which dominated in the Ordovician, taxonomic evolutionary rates were relatively low and the probability of extinction was highest among newly evolved species (“background extinction mode”). A sharp change in extinction regime in the Late Ordovician marked the onset of repeated severe spikes in the extinction rate curve; evolutionary turnover increased greatly in the Silurian, and the extinction mode changed to include extinction that was independent of species age (“high-extinction mode”). This change coincides with a change in global climate, from greenhouse to icehouse conditions. During the most extreme episode of extinction, the Late Ordovician Mass Extinction, old species were selectively removed (“mass extinction mode”). Our analysis indicates that selective regimes in the Paleozoic ocean plankton switched rapidly (generally in <0.5 My) from one mode to another in response to environmental change, even when restoration of the full ecosystem was much slower (several million years). The patterns observed are not a simple consequence of geographic range effects or of taxonomic changes from Ordovician to Silurian. Our results suggest that the dominant primary controls on extinction throughout the lifespan of this clade were abiotic (environmental), probably mediated by the microphytoplankton. PMID:26811471

  16. Bridging the gap between omics and earth system science to better understand how environmental change impacts marine microbes.

    PubMed

    Mock, Thomas; Daines, Stuart J; Geider, Richard; Collins, Sinead; Metodiev, Metodi; Millar, Andrew J; Moulton, Vincent; Lenton, Timothy M

    2016-01-01

    The advent of genomic-, transcriptomic- and proteomic-based approaches has revolutionized our ability to describe marine microbial communities, including biogeography, metabolic potential and diversity, mechanisms of adaptation, and phylogeny and evolutionary history. New interdisciplinary approaches are needed to move from this descriptive level to improved quantitative, process-level understanding of the roles of marine microbes in biogeochemical cycles and of the impact of environmental change on the marine microbial ecosystem. Linking studies at levels from the genome to the organism, to ecological strategies and organism and ecosystem response, requires new modelling approaches. Key to this will be a fundamental shift in modelling scale that represents micro-organisms from the level of their macromolecular components. This will enable contact with omics data sets and allow acclimation and adaptive response at the phenotype level (i.e. traits) to be simulated as a combination of fitness maximization and evolutionary constraints. This way forward will build on ecological approaches that identify key organism traits and systems biology approaches that integrate traditional physiological measurements with new insights from omics. It will rely on developing an improved understanding of ecophysiology to understand quantitatively environmental controls on microbial growth strategies. It will also incorporate results from experimental evolution studies in the representation of adaptation. The resulting ecosystem-level models can then evaluate our level of understanding of controls on ecosystem structure and function, highlight major gaps in understanding and help prioritize areas for future research programs. Ultimately, this grand synthesis should improve predictive capability of the ecosystem response to multiple environmental drivers.

  17. Changing Arctic ecosystems--research to understand and project changes in marine and terrestrial ecosystems of the Arctic

    USGS Publications Warehouse

    Geiselman, Joy; DeGange, Anthony R.; Oakley, Karen; Derksen, Dirk; Whalen, Mary

    2012-01-01

    Ecosystems and their wildlife communities are not static; they change and evolve over time due to numerous intrinsic and extrinsic factors. A period of rapid change is occurring in the Arctic for which our current understanding of potential ecosystem and wildlife responses is limited. Changes to the physical environment include warming temperatures, diminishing sea ice, increasing coastal erosion, deteriorating permafrost, and changing water regimes. These changes influence biological communities and the ways in which human communities interact with them. Through the new initiative Changing Arctic Ecosystems (CAE) the U.S. Geological Survey (USGS) strives to (1) understand the potential suite of wildlife population responses to these physical changes to inform key resource management decisions such as those related to the Endangered Species Act, and (2) provide unique insights into how Arctic ecosystems are responding under new stressors. Our studies examine how and why changes in the ice-dominated ecosystems of the Arctic are affecting wildlife and will provide a better foundation for understanding the degree and manner in which wildlife species respond and adapt to rapid environmental change. Changes to Arctic ecosystems will be felt broadly because the Arctic is a production zone for hundreds of species that migrate south for the winter. The CAE initiative includes three major research themes that span Arctic ice-dominated ecosystems and that are structured to identify and understand the linkages between physical processes, ecosystems, and wildlife populations. The USGS is applying knowledge-based modeling structures such as Bayesian Networks to integrate the work.

  18. Markov chain analysis of succession in a rocky subtidal community.

    PubMed

    Hill, M Forrest; Witman, Jon D; Caswell, Hal

    2004-08-01

    We present a Markov chain model of succession in a rocky subtidal community based on a long-term (1986-1994) study of subtidal invertebrates (14 species) at Ammen Rock Pinnacle in the Gulf of Maine. The model describes successional processes (disturbance, colonization, species persistence, and replacement), the equilibrium (stationary) community, and the rate of convergence. We described successional dynamics by species turnover rates, recurrence times, and the entropy of the transition matrix. We used perturbation analysis to quantify the response of diversity to successional rates and species removals. The equilibrium community was dominated by an encrusting sponge (Hymedesmia) and a bryozoan (Crisia eburnea). The equilibrium structure explained 98% of the variance in observed species frequencies. Dominant species have low probabilities of disturbance and high rates of colonization and persistence. On average, species turn over every 3.4 years. Recurrence times varied among species (7-268 years); rare species had the longest recurrence times. The community converged to equilibrium quickly (9.5 years), as measured by Dobrushin's coefficient of ergodicity. The largest changes in evenness would result from removal of the dominant sponge Hymedesmia. Subdominant species appear to increase evenness by slowing the dominance of Hymedesmia. Comparison of the subtidal community with intertidal and coral reef communities revealed that disturbance rates are an order of magnitude higher in coral reef than in rocky intertidal and subtidal communities. Colonization rates and turnover times, however, are lowest and longest in coral reefs, highest and shortest in intertidal communities, and intermediate in subtidal communities.

  19. Rocky Mountain spotted fever: a clinician's dilemma.

    PubMed

    Masters, Edwin J; Olson, Gary S; Weiner, Scott J; Paddock, Christopher D

    2003-04-14

    Rocky Mountain spotted fever is still the most lethal tick-vectored illness in the United States. We examine the dilemmas facing the clinician who is evaluating the patient with possible Rocky Mountain spotted fever, with particular attention to the following 8 pitfalls in diagnosis and treatment: (1) waiting for a petechial rash to develop before diagnosis; (2) misdiagnosing as gastroenteritis; (3) discounting a diagnosis when there is no history of a tick bite; (4) using an inappropriate geographic exclusion; (5) using an inappropriate seasonal exclusion; (6) failing to treat on clinical suspicion; (7) failing to elicit an appropriate history; and (8) failing to treat with doxycycline. Early diagnosis and proper treatment save lives.

  20. Eocene upper shoreface facies from the Circum-Rhodope belt, NE Greece: sedimentological evidence for an ancient rocky shore environment

    NASA Astrophysics Data System (ADS)

    Chatalov, Atanas; Ivanova, Daria; Bonev, Nikolay

    2013-04-01

    lithofacies transitions, small-scale cycles, and internal key stratal surfaces in the Eocene rocks testifies that the upper shoreface deposits were accumulated during a single transgressive phase. The particular absence of convincingly recognized beachface facies can be explained with the so called "cannibalization" mechanism (cf. Sheppard, 2006). The present-day exposures of the basement and covering rocks are consistent with the assumption of a paleoisland having homogeneous lithology. The prolonged erosional destruction of its rocky coast was gradually terminated and after the cessation of marine wave-cutting processes and contemporaneous deposition the remaining emerged cliffs of Lower Cretaceous limestones were continuously degraded by subaerial processes. The obtained results may elucidate the geological evolution of the hydrocarbon-bearing Thrace Basin and to promote the basin-wide correlation of its thick (~9000 m) sedimentary record. Acknowledgments: This study was supported by the National Science Fund of Bulgaria, Grant DDVU 02/94. References Cattaneo, A., R. J. Steel. 2003. Transgressive deposits: a review of their variability. - Earth Sci. Rev., 62, 187-228. Sheppard, T. H. 2006. Sequence architecture of ancient rocky shorelines and their response to sea-level change: an Early Jurassic example from South Wales, UK. - Jour. Geol. Soc. London, 163, 595-606.

  1. Microwave solidification development for Rocky Flats waste

    SciTech Connect

    Dixon, D.; Erle, R.; Eschen, V.

    1994-04-01

    The Microwave Engineering Team at the Rocky Flats Plant has developed a production-scale system for the treatment of hazardous, radioactive, and mixed wastes using microwave energy. The system produces a vitreous final form which meets the acceptance criteria for shipment and disposal. The technology also has potential for application on various other waste streams from the public and private sectors. Technology transfer opportunities are being identified and pursued for commercialization of the microwave solidification technology.

  2. Status Update: Closing Rocky Flats by 2006

    SciTech Connect

    Tuor, N.; Schubert, A.

    2003-02-25

    Safely closing Rocky Flats by December 2006 is a goal shared by many: the State of Colorado, the communities surrounding the site, the U.S. Congress, the Department of Energy (DOE), Kaiser-Hill and its team of subcontractors, the site's employees and taxpayers across the country. This paper will: provide a status of the Closure Project to date; describe important accomplishments of the past year; describe some of the closure-enhancing technologies enabling acceleration; and discuss the remaining challenges ahead.

  3. THERMODYNAMIC LIMITS ON MAGNETODYNAMOS IN ROCKY EXOPLANETS

    SciTech Connect

    Gaidos, Eric; Conrad, Clinton P.; Manga, Michael; Hernlund, John

    2010-08-01

    To ascertain whether magnetic dynamos operate in rocky exoplanets more massive or hotter than the Earth, we developed a parametric model of a differentiated rocky planet and its thermal evolution. Our model reproduces the established properties of Earth's interior and magnetic field at the present time. When applied to Venus, assuming that planet lacks plate tectonics and has a dehydrated mantle with an elevated viscosity, the model shows that the dynamo shuts down or never operated. Our model predicts that at a fixed planet mass, dynamo history is sensitive to core size, but not to the initial inventory of long-lived, heat-producing radionuclides. It predicts that rocky planets larger than 2.5 Earth masses will not develop inner cores because the temperature-pressure slope of the iron solidus becomes flatter than that of the core adiabat. Instead, iron 'snow' will condense near or at the top of these cores, and the net transfer of latent heat upward will suppress convection and a dynamo. More massive planets can have anemic dynamos due to core cooling, but only if they have mobile lids (plate tectonics). The lifetime of these dynamos is shorter with increasing planet mass but longer with higher surface temperature. Massive Venus-like planets with stagnant lids and more viscous mantles will lack dynamos altogether. We identify two alternative sources of magnetic fields on rocky planets: eddy currents induced in the hot or molten upper layers of planets on very short-period orbits, and dynamos in the ionic conducting layers of 'ocean' planets with {approx}10% mass in an upper mantle of water (ice).

  4. Rocky Mountain futures: An ecological perspective

    USGS Publications Warehouse

    Baron, Jill S.

    2002-01-01

    The United Nations has proclaimed 2002 as the International Year of Mountains to increase international awareness of the global importance of mountain ecosystems. The case-based multidisciplinary approach of this book constitutes an important new model for understanding the implications of land-use practices and economic activity on mountains, and will serve a vital role in improving decisionmaking both in the Rocky Mountains and in other parts of the world that face similar challenges.

  5. Thermodynamic Limits on Magnetodynamos in Rocky Exoplanets

    NASA Astrophysics Data System (ADS)

    Gaidos, Eric; Conrad, Clinton P.; Manga, Michael; Hernlund, John

    2010-08-01

    To ascertain whether magnetic dynamos operate in rocky exoplanets more massive or hotter than the Earth, we developed a parametric model of a differentiated rocky planet and its thermal evolution. Our model reproduces the established properties of Earth's interior and magnetic field at the present time. When applied to Venus, assuming that planet lacks plate tectonics and has a dehydrated mantle with an elevated viscosity, the model shows that the dynamo shuts down or never operated. Our model predicts that at a fixed planet mass, dynamo history is sensitive to core size, but not to the initial inventory of long-lived, heat-producing radionuclides. It predicts that rocky planets larger than 2.5 Earth masses will not develop inner cores because the temperature-pressure slope of the iron solidus becomes flatter than that of the core adiabat. Instead, iron "snow" will condense near or at the top of these cores, and the net transfer of latent heat upward will suppress convection and a dynamo. More massive planets can have anemic dynamos due to core cooling, but only if they have mobile lids (plate tectonics). The lifetime of these dynamos is shorter with increasing planet mass but longer with higher surface temperature. Massive Venus-like planets with stagnant lids and more viscous mantles will lack dynamos altogether. We identify two alternative sources of magnetic fields on rocky planets: eddy currents induced in the hot or molten upper layers of planets on very short-period orbits, and dynamos in the ionic conducting layers of "ocean" planets with ~10% mass in an upper mantle of water (ice).

  6. Strain monitoring averts line failure in Rockies

    SciTech Connect

    Miller, B.; Bukovansky, M.

    1987-08-10

    The case history of a landslide in the U.S. Rocky Mountains shows that the potential for pipeline monitoring in geologically sensitive areas, those subject to landslides and subsidence, for example. A properly installed monitoring system monitored by the pipeline operator, Western Gas Supply Co. (West Gas), Denver, provided an early warning of increasing line strains. The problem was complicated by rugged topography which is described here. Stability analysis was the key technique utilized in the process.

  7. Climate change is projected to reduce carrying capacity and redistribute species richness in North Pacific pelagic marine ecosystems.

    PubMed

    Woodworth-Jefcoats, Phoebe A; Polovina, Jeffrey J; Drazen, Jeffrey C

    2017-03-01

    Climate change is expected to impact all aspects of marine ecosystems, including fisheries. Here, we use output from a suite of 11 earth system models to examine projected changes in two ecosystem-defining variables: temperature and food availability. In particular, we examine projected changes in epipelagic temperature and, as a proxy for food availability, zooplankton density. We find that under RCP8.5, a high business-as-usual greenhouse gas scenario, increasing temperatures may alter the spatial distribution of tuna and billfish species richness across the North Pacific basin. Furthermore, warmer waters and declining zooplankton densities may act together to lower carrying capacity for commercially valuable fish by 2-5% per decade over the 21st century. These changes have the potential to significantly impact the magnitude, composition, and distribution of commercial fish catch across the pelagic North Pacific. Such changes will in turn ultimately impact commercial fisheries' economic value. Fishery managers should anticipate these climate impacts to ensure sustainable fishery yields and livelihoods.

  8. Changes in algal community structure via density- and trait-mediated indirect interactions in a marine ecosystem.

    PubMed

    Wada, Yoko; Iwasaki, Keiji; Yusa, Yoichi

    2013-11-01

    In various terrestrial and aquatic ecosystems, predators affect resources indirectly via intermediate prey. Such indirect interactions involve reducing the density of the prey (density-mediated indirect interactions, DMIIs) or changing the behavioral, morphological, or life history traits of the prey (trait-mediated indirect interactions, TMIIs). Although the importance of TMIIs has been highlighted recently, the strengths of both DMIIs and TMIIs under natural conditions have rarely been evaluated, especially in the context of resource community structure. We studied a three-level marine food chain involving the carnivorous snail Thais clavigera, its limpet prey Siphonaria sirius, and the limpet's food sources, the algae Lithoderma sp. and Ulva sp. We measured the strengths of DMIIs and TMIIs and observed how the algal community changes under the pressure of natural predation by T. clavigera on S. sirius. Neither DMIIs nor TMIIs affected the total algal cover or chlorophyll content per unit area. However, both types of indirect interactions caused similar changes in algal composition by increasing the cover of Ulva and decreasing the cover of Lithoderma. This change in the algal community was caused by a reduction in the limpet's preferential consumption of the competitively dominant Ulva over Lithoderma. These results suggest that both DMIIs and TMIIs have similar effects on the changes in resource community structure under natural conditions.

  9. Resistance to Total Quality Leadership Change: An Evaluation of Individual Marine Responses to TQL Principles and Change

    DTIC Science & Technology

    1991-12-01

    fundamental, descriptions of the process of change was developed by Kurt Lewin , an organizational theorist, in 1947. As depicted in Figure 1, Lewin’s view of...influenced by the works and concepts of Kurt Lewin , Coch and French sought to identify the reason people resist 27 change so strongly and to describe

  10. Atmospheric deposition maps for the Rocky Mountains

    USGS Publications Warehouse

    Nanus, L.; Campbell, D.H.; Ingersoll, G.P.; Clow, D.W.; Mast, M.A.

    2003-01-01

    Variability in atmospheric deposition across the Rocky Mountains is influenced by elevation, slope, aspect, and precipitation amount and by regional and local sources of air pollution. To improve estimates of deposition in mountainous regions, maps of average annual atmospheric deposition loadings of nitrate, sulfate, and acidity were developed for the Rocky Mountains by using spatial statistics. A parameter-elevation regressions on independent slopes model (PRISM) was incorporated to account for variations in precipitation amount over mountainous regions. Chemical data were obtained from the National Atmospheric Deposition Program/National Trends Network and from annual snowpack surveys conducted by the US Geological Survey and National Park Service, in cooperation with other Federal, State and local agencies. Surface concentration maps were created by ordinary kriging in a geographic information system, using a local trend and mathematical model to estimate the spatial variance. Atmospheric-deposition maps were constructed at 1-km resolution by multiplying surface concentrations from the kriged grid and estimates of precipitation amount from the PRISM model. Maps indicate an increasing spatial trend in concentration and deposition of the modeled constituents, particularly nitrate and sulfate, from north to south throughout the Rocky Mountains and identify hot-spots of atmospheric deposition that result from combined local and regional sources of air pollution. Highest nitrate (2.5-3.0kg/ha N) and sulfate (10.0-12.0kg/ha SO4) deposition is found in northern Colorado.

  11. Numerical Modeling of the Snowmass Creek Paleoglacier, Colorado: Implications for Middle and Late Pleistocene climate in the Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Leonard, E. M.; Plummer, M. A.; Carrara, P. E.

    2013-12-01

    Well-preserved moraines from the last two glaciations of the Snowmass Creek valley in the Elk Range of Colorado present an opportunity to examine the character of the high-altitude climate in the Rocky Mountains during marine isotope stages 6 and 2. This study employs a 2-D coupled energy/mass balance and flow model (Plummer and Phillips, 2003) to assess the magnitudes of temperature and precipitation change that could have sustained the glacier in mass-balance equilibrium at its maximum extents during the penultimate (MIS 6 or Bull Lake) glaciation and the last glacial maximum (MIS 2 or Pinedale). Variable substrate effects on glacier flow and ice thickness make the modeling somewhat more complex than in geologically simpler settings. Model results indicate that a temperature depression of about 6.4°C compared to the modern (1971-2000AD) would have been necessary to sustain the 26 km-long Snowmass Creek glacier in mass balance equilibrium during the Bull Lake glaciation, assuming no change from the modern in precipitation amount or seasonality. Uncertainty in the modeling is about 1°C. A 50 percent increase or decrease from modern precipitation would have been coupled with 4.8°C and 8.8°C Bull Lake temperature depressions respectively. The maximum extent of the glacier during MIS 2 or Pinedale glaciation is somewhat less clear. Moraines confidently assigned to the Pinedale glaciation indicate a temperature depression of about 6.1°C, assuming no change in precipitation. An intermediate set of moraines which may be Pinedale in age, would suggest a Pinedale temperature depression very close to that of the Bull Lake glaciation. These Pinedale temperature depression estimates are comparable to those obtained using the same model in three other Colorado ranges (5.5 - 6.8°C with no change in precipitation) and slightly less than those previously obtained using a variety of other paleoglaciological methods (6.4 to 8.5°C with no change in precipitation). The Bull

  12. Marine historical ecology at the Brijuni Islands, Croatia: preliminary results from down-core changes of foraminiferal assemblages

    NASA Astrophysics Data System (ADS)

    Vidovic, Jelena; Cosovic, Vlasta; Gallmetzer, Ivo; Haselmair, Alexandra; Zuschin, Martin

    2015-04-01

    The Late Holocene in the northern Adriatic is characterized by the eustatic peak of the sea-level rise, followed by the equilibrium between the regional tectonic subsidence and hydro-isostatic emergence and relatively stable sea level for a few thousand years. During this period the area experienced changes in sedimentation rate, food/oxygen availability in the benthic ecosystem and eutrophication with seasonal hypoxic and anoxic events. In order to reconstruct the marine paleoecology in the Brijuni Islands area during this period, a multidisciplinary study was carried out, including geochemical (TOC, trace metals, carbonate content), micropaleontological analyses (benthic foraminifera) and dating of sediments and mollusc shells. The principal aim of this study is to observe the effects of ecological shifts on foraminiferal assemblages during the Late Holocene. One core of 1.5 m length was taken at a sampling station south of Veli Brijuni Island, located within a marine protected area with no fishing/dredging pressure (Croatian national park). The core was sliced into smaller subsamples, and four sediment fractions of each subsample (63, 125, 250 and 500 µm) were analyzed for standard properties of the foraminiferal community (species richness, faunal composition, biodiversity indices), in comparison with relevant physical and geochemical properties of the sediment. The results concerning changes in foraminiferal species composition and abundance point to differences within the core: surface sediments are dominated by suspension feeders (Planorbulina mediterranensis, Lobatula lobatula, Cibicides variabilis, Cibicides refulgens), whereas deposit feeders (genera Textularia, Siphonaperta, Adelosina, Trioculina) appear in higher abundances at approximately 30 cm of the sediment depth and dominate down-core. Species richness in the first 30 cm is lower (10 to 34 species per sample) in comparison to the middle part of the core (39 to 53 species), and decreases again at

  13. [Diversity, abundance and distribution of benthic macrofauna on rocky shores from North Sucre State, Venezuela].

    PubMed

    Fernandez, Johanna; Jiménez, Mayré; Allen, Thays

    2014-09-01

    The rocky intertidal zone is among the most extreme physical environments on Earth. Organisms living in this area are constantly stricken by physico-chemical and biological factors. Due to the ecological importance of these areas, we studied the diversity, abundance and distribution of the rocky coastline benthic macrofauna, from the North coast of Sucre State, Venezuela. We performed bimonthly samplings from November 2008 to September 2009. The collection of biological material in the littoral zone (supra, mid and infralittoral) was done manually with a grid of 0.25m2. Organisms were preserved in 10% formalin for later identification and analysis (ecological parameters and Kruskal-Wallis test to the abundance and diversity). We found a total 19,020 organisms (86 spp.), in 8 phyla, 45 families and 47 genera. Mollusks were the most abundant and diverse (58 spp.), followed by arthropods (12 spp.), annelids (7 spp.), echinoderms (5 spp.), and the less represented cnidarians, sipunculids, nemertinids and urochordates (1 sp.). The zonation found coincided with the universal scheme of zonation. The towns of Rio Boca and Rio Caribe presented the highest values of ecological parameters, and the lowest were found in Playa Grande. Statistical significant differences were found in the abundance and diversity of macrofauna among the three zones. The little information on the composition and distribution of macrobenthic rocky coastline, prevents a better comparison, however the results contribute to the knowledge of the marine biodiversity in this region.

  14. Distinguishing globally-driven changes from regional- and local-scale impacts: The case for long-term and broad-scale studies of recovery from pollution.

    PubMed

    Hawkins, S J; Evans, A J; Mieszkowska, N; Adams, L C; Bray, S; Burrows, M T; Firth, L B; Genner, M J; Leung, K M Y; Moore, P J; Pack, K; Schuster, H; Sims, D W; Whittington, M; Southward, E C

    2017-03-14

    Marine ecosystems are subject to anthropogenic change at global, regional and local scales. Global drivers interact with regional- and local-scale impacts of both a chronic and acute nature. Natural fluctuations and those driven by climate change need to be understood to diagnose local- and regional-scale impacts, and to inform assessments of recovery. Three case studies are used to illustrate the need for long-term studies: (i) separation of the influence of fishing pressure from climate change on bottom fish in the English Channel; (ii) recovery of rocky shore assemblages from the Torrey Canyon oil spill in the southwest of England; (iii) interaction of climate change and chronic Tributyltin pollution affecting recovery of rocky shore populations following the Torrey Canyon oil spill. We emphasize that "baselines" or "reference states" are better viewed as envelopes that are dependent on the time window of observation. Recommendations are made for adaptive management in a rapidly changing world.

  15. Shifts in Microbial Community Structure with Changes in Cathodic Potential in Marine Sediment Microcosms

    NASA Astrophysics Data System (ADS)

    Lam, B. R.; Rowe, A. R.; Nealson, K. H.

    2014-12-01

    Microorganisms comprise more than 90% of the biomass of the ocean. Their ability to thrive and survive in a wide range of environments from oligotrophic waters to the deep subsurface stems from the great metabolic versatility that exists among them. This metabolic versatility has further expanded with the discovery of extracellular electron transport (EET). EET is the capability of microorganisms to transfer electrons to and from insoluble substrates outside of the cell. Much of what is known about EET comes from studies of model metal reducing microorganisms in the groups Shewanellaceae and Geobacteraceae. However, EET is not limited to these metal reducing microorganisms, and may play a large role in the biogeochemical cycling of several elements. We have developed an electrochemical culturing technique designed to target microorganisms with EET ability and tested these methods in marine sediments. The use of electrodes allows for greater control and quantification of electrons flowing to insoluble substrates as opposed to insoluble substrates such as minerals that are often difficult to measure. We have recently shown that poising electrodes at different redox potentials will enrich for different microbial groups and thus possible metabolisms. In marine sediment microcosms, triplicate electrodes were poised at different cathodic (electron donating) potentials (-300, -400, -500 and -600 mV) and incubated for eight weeks. Community analysis of the 16S rRNA revealed that at lower negative potentials (-500 and -600 mV), more sulfate reducing bacteria in the class Deltaproteobacteria were enriched in comparison to the communities at -300 and -400 mV being dominated by microorganisms within Alphaproteobacteria, Gammaproteobacteria, and Clostridia. This can be explained by sulfate (abundant in seawater) becoming a more energetically favorable electron acceptor with lower applied potentials. In addition, communities at higher potentials showed greater enrichment of the

  16. Contrasting environmental drivers of adult and juvenile growth in a marine fish: implications for the effects of climate change

    PubMed Central

    Ong, Joyce Jia Lin; Nicholas Rountrey, Adam; Jane Meeuwig, Jessica; John Newman, Stephen; Zinke, Jens; Gregory Meekan, Mark

    2015-01-01

    Many marine fishes have life history strategies that involve ontogenetic changes in the use of coastal habitats. Such ontogenetic shifts may place these species at particular risk from climate change, because the successive environments they inhabit can differ in the type, frequency and severity of changes related to global warming. We used a dendrochronology approach to examine the physical and biological drivers of growth of adult and juvenile mangrove jack (Lutjanus argentimaculatus) from tropical north-western Australia. Juveniles of this species inhabit estuarine environments and adults reside on coastal reefs. The Niño-4 index, a measure of the status of the El Niño-Southern Oscillation (ENSO) had the highest correlation with adult growth chronologies, with La Niña years (characterised by warmer temperatures and lower salinities) having positive impacts on growth. Atmospheric and oceanographic phenomena operating at ocean-basin scales seem to be important correlates of the processes driving growth in local coastal habitats. Conversely, terrestrial factors influencing precipitation and river runoff were positively correlated with the growth of juveniles in estuaries. Our results show that the impacts of climate change on these two life history stages are likely to be different, with implications for resilience and management of populations. PMID:26052896

  17. Contrasting environmental drivers of adult and juvenile growth in a marine fish: implications for the effects of climate change.

    PubMed

    Ong, Joyce Jia Lin; Rountrey, Adam Nicholas; Meeuwig, Jessica Jane; Newman, Stephen John; Zinke, Jens; Meekan, Mark Gregory

    2015-06-08

    Many marine fishes have life history strategies that involve ontogenetic changes in the use of coastal habitats. Such ontogenetic shifts may place these species at particular risk from climate change, because the successive environments they inhabit can differ in the type, frequency and severity of changes related to global warming. We used a dendrochronology approach to examine the physical and biological drivers of growth of adult and juvenile mangrove jack (Lutjanus argentimaculatus) from tropical north-western Australia. Juveniles of this species inhabit estuarine environments and adults reside on coastal reefs. The Niño-4 index, a measure of the status of the El Niño-Southern Oscillation (ENSO) had the highest correlation with adult growth chronologies, with La Niña years (characterised by warmer temperatures and lower salinities) having positive impacts on growth. Atmospheric and oceanographic phenomena operating at ocean-basin scales seem to be important correlates of the processes driving growth in local coastal habitats. Conversely, terrestrial factors influencing precipitation and river runoff were positively correlated with the growth of juveniles in estuaries. Our results show that the impacts of climate change on these two life history stages are likely to be different, with implications for resilience and management of populations.

  18. Effects of petrochemical contamination on caged marine mussels using a multi-biomarker approach: Histological changes, neurotoxicity and hypoxic stress.

    PubMed

    Maisano, Maria; Cappello, Tiziana; Natalotto, Antonino; Vitale, Valeria; Parrino, Vincenzo; Giannetto, Alessia; Oliva, Sabrina; Mancini, Giuseppe; Cappello, Simone; Mauceri, Angela; Fasulo, Salvatore

    2016-03-31

    This work was designed to evaluate the biological effects of petrochemical contamination on marine mussels. Mytilus galloprovincialis, widely used as sentinel organisms in biomonitoring studies, were caged at the "Augusta-Melilli-Priolo" industrial site (eastern Sicily, Italy), chosen as one of the largest petrochemical areas in Europe, and Brucoli, chosen as reference site. Chemical analyses of sediments at the polluted site revealed high levels of PAHs and mercury, exceeding the national and international guideline limits. In mussels from the polluted site, severe morphological alterations were observed in gills, mainly involved in nutrient uptake and gas exchange. Changes in serotonergic and cholinergic systems, investigated through immunohistochemical, metabolomics and enzymatic approaches, were highlighted in gills, as well as onset of hypoxic adaptive responses with up-regulation of hypoxia-inducible factor transcript. Overall, the application of a multi-biomarker panel results effective in assessing the biological effects of petrochemical contamination on the health of aquatic organisms.

  19. Linked changes in marine dissolved organic carbon molecular size and radiocarbon age

    NASA Astrophysics Data System (ADS)

    Walker, B. D.; Primeau, F. W.; Beaupré, S. R.; Guilderson, T. P.; Druffel, E. R. M.; McCarthy, M. D.

    2016-10-01

    Marine dissolved organic carbon (DOC) is a major global carbon reservoir, yet its cycling remains poorly understood. Previous work suggests that DOC molecular size and chemical composition can significantly affect its bioavailability. Thus, DOC size and composition may control DOC cycling and radiocarbon age (via Δ14C). Here we show that DOC molecular size is correlated to DOC Δ14C in the Pacific Ocean. Our results, based on a series of increasing molecular size fractions from three depths in the Pacific, show increasing DOC Δ14C with increasing molecular size. We use a size-age distribution model to predict the DOC and Δ14C of ultrafiltered DOC. The model predicts both large and small surface DOC with high Δ14C and a narrow range (200-500 Da) of low Δ14C DOC. Deep model offsets suggest different size distributions and/or Δ14C sources at 670-915 m. Our results suggest that molecular size and composition are linked to DOC reactivity and storage in the ocean.

  20. Sea ice proxies, marine environmental change, and human societies in Northwest Greenland over the past ca. 4500 years

    NASA Astrophysics Data System (ADS)

    Ribeiro, Sofia; Weckström, Kaarina; Tallberg, Petra; Risager Kjøller, Marianne; Limoges, Audrey; Massé, Guillaume; Nissen, Martin; Toudal Pedersen, Leif; Mikkelsen, Naja

    2016-04-01

    Greenland has been inhabited for only ca. 4500 years, but several human colonization events and cultural transitions occurred during this period. This work is part of the ICE-ARC project - Ice, Climate and Economics in the Arctic (EU FP7), aimed at understanding and quantifying the multiple stresses involved in the change in the Arctic marine environment, with particular focus on the rapid retreat and collapse of the Arctic sea ice cover. The overall goal of the project is to assess the climatic (ice, ocean, atmosphere and ecosystem), economic and social impacts of these stresses on regional and global scales. Marine sediment cores were retrieved from the Inglefield Bredning fjord system in the Qaanaaq region, Northwest Greenland, and are being analysed for various climate and environmental proxies, including biological indicators (e.g. dinoflagellate cysts, diatoms), biogeochemical elements (biogenic silica, XRF scanning), and sea-ice specific biomarkers (IP25). We will present the first data from this core material, consisting of a spatial study of sea ice and productivity proxies in 13 surface sediment samples (IP25, biogenic silica, diatoms, and dinoflagellate cysts) which will be compared with satellite-derived sea ice cover data for the Qaanaaq region/ northern Baffin Bay. This spatial study will serve as basis to reconstruct sea ice variability in the area over the past ca. 4500 years, and will be combined with historical and archaeological data in order to identify possible links between past changes in climate and sea ice conditions, and events of human migration and cultural transition in Greenland.

  1. Habitat-associations of turban snails on intertidal and subtidal rocky reefs.

    PubMed

    Smoothey, Amy F

    2013-01-01

    Patchiness of habitat has important influences on distributions and abundances of organisms. Given the increasing threat of loss and alteration of habitats due to pressures associated with humans, there is a need for ecologists to understand species' requirements for habitat and to predict changes to taxa under various future environmental conditions. This study tested hypotheses about the generality of patterns described for one species of marine intertidal turban snail for a different, yet closely-related species in subtidal habitats along the coast of New South Wales, Australia. These two closely-related species live in similar habitats, yet under quite different conditions, which provided an opportunity to investigate how similar types of habitats influence patterns of distribution, abundance and size-structure in intertidal versus subtidal environments. For each species, there were similar associations between biogenically structured habitat and densities. The intertidal species, Turbo undulates, were more abundant, with greater proportions of small individuals in habitats formed by the canopy-forming alga, Hormosira banksii, the solitary ascidian, Pyura stolonifera or the turfing red alga, Corallina officinalis compared to simple habitat (bare rock). Similarly, more Turbo torquatus were found in biogenically structured subtidal habitat, i.e. canopy-forming algae, Ecklonia radiata, mixed algal communities ('fringe'), or turfing red algae (Corallina officinalis and Amphiroa aniceps) than where habitat is simple (barrens). Small T. torquatus were more abundant in areas of turf and 'fringe', while large snails were more abundant in areas of kelp and barrens. These patterns were found at each location sampled (i.e. eight intertidal and two subtidal rocky reefs) and at all times of sampling, across each environment. This study highlighted the consistent influence of biogenically structured habitats on the distribution, abundance and size-structure of intertidal and

  2. Habitat-Associations of Turban Snails on Intertidal and Subtidal Rocky Reefs

    PubMed Central

    Smoothey, Amy F.

    2013-01-01

    Patchiness of habitat has important influences on distributions and abundances of organisms. Given the increasing threat of loss and alteration of habitats due to pressures associated with humans, there is a need for ecologists to understand species' requirements for habitat and to predict changes to taxa under various future environmental conditions. This study tested hypotheses about the generality of patterns described for one species of marine intertidal turban snail for a different, yet closely-related species in subtidal habitats along the coast of New South Wales, Australia. These two closely-related species live in similar habitats, yet under quite different conditions, which provided an opportunity to investigate how similar types of habitats influence patterns of distribution, abundance and size-structure in intertidal versus subtidal environments. For each species, there were similar associations between biogenically structured habitat and densities. The intertidal species, Turbo undulates, were more abundant, with greater proportions of small individuals in habitats formed by the canopy-forming alga, Hormosira banksii, the solitary ascidian, Pyura stolonifera or the turfing red alga, Corallina officinalis compared to simple habitat (bare rock). Similarly, more Turbo torquatus were found in biogenically structured subtidal habitat, i.e. canopy-forming algae, Ecklonia radiata, mixed algal communities (‘fringe’), or turfing red algae (Corallina officinalis and Amphiroa aniceps) than where habitat is simple (barrens). Small T. torquatus were more abundant in areas of turf and ‘fringe’, while large snails were more abundant in areas of kelp and barrens. These patterns were found at each location sampled (i.e. eight intertidal and two subtidal rocky reefs) and at all times of sampling, across each environment. This study highlighted the consistent influence of biogenically structured habitats on the distribution, abundance and size-structure of

  3. Changes in Eocene-Miocene shallow marine carbonate factories along the tropical SE Circum-Caribbean responded to major regional and global environmental and tectonic events

    NASA Astrophysics Data System (ADS)

    Silva-Tamayo, Juan Carlos

    2015-04-01

    Changes in the factory of Cenozoic tropical marine carbonates have been for long attributed to major variations on climatic and environmental conditions. Although important changes on the factories of Cenozoic Caribbean carbonates seem to have followed global climatic and environmental changes, the regional impact of such changes on the factories of shallow marine carbonate along the Caribbean is not well established. Moreover, the influence of transpressional tectonics on the occurrence, distribution and stratigraphy of shallow marine carbonate factories along this area is far from being well understood. Here we report detailed stratigraphic, petrographic and Sr-isotope chemostratigraphic information of several Eocene-Miocene carbonate successions deposited along the equatorial/tropical SE Circum-Caribbean (Colombia and Panama) from which we further assess the influence of changing environmental conditions, transtentional tectonics and sea level change on the development of the shallow marine carbonate factories. Our results suggest that during the Eocene-early Oligocene interval, a period of predominant high atmospheric pCO2, coralline algae constitute the principal carbonate builders of shallow marine carbonate successions along the SE Circum-Caribbean. Detailed stratigraphic and paragenetic analyses suggest the developed of laterally continuous red algae calcareous build-ups along outer-rimmed carbonate platforms. The predominance of coralline red algae over corals on the shallow marine carbonate factories was likely related to high sea surface temperatures and high turbidity. The occurrence of such build-ups was likely controlled by pronounce changes in the basin paleotopography, i.e. the occurrence of basement highs and lows, resulting from local transpressional tectonics. The occurrence of these calcareous red algae dominated factories was also controlled by diachronic opening of different sedimentary basins along the SE Circum Caribbean resulting from

  4. Temperature change affected groundwater quality in a confined marine aquifer during long-term heating and cooling.

    PubMed

    Saito, Takeshi; Hamamoto, Shoichiro; Ueki, Takashi; Ohkubo, Satoshi; Moldrup, Per; Kawamoto, Ken; Komatsu, Toshiko

    2016-05-01

    Global warming and urbanization together with development of subsurface infrastructures (e.g. subways, shopping complexes, sewage systems, and Ground Source Heat Pump (GSHP) systems) will likely cause a rapid increase in the temperature of relatively shallow groundwater reservoirs (subsurface thermal pollution). However, potential effects of a subsurface temperature change on groundwater quality due to changed physical, chemical, and microbial processes have received little attention. We therefore investigated changes in 34 groundwater quality parameters during a 13-month enhanced-heating period, followed by 14 months of natural or enhanced cooling in a confined marine aquifer at around 17 m depth on the Saitama University campus, Japan. A full-scale GSHP test facility consisting of a 50 m deep U-tube for circulating the heat-carrying fluid and four monitoring wells at 1, 2, 5, and 10 m from the U-tube were installed, and groundwater quality was monitored every 1-2 weeks. Rapid changes in the groundwater level in the area, especially during the summer, prevented accurate analyses of temperature effects using a single-well time series. Instead, Dual-Well Analysis (DWA) was applied, comparing variations in subsurface temperature and groundwater chemical concentrations between the thermally-disturbed well and a non-affected reference well. Using the 1 m distant well (temperature increase up to 7 °C) and the 10 m distant well (non-temperature-affected), the DWA showed an approximately linear relationships for eight components (B, Si, Li, dissolved organic carbon (DOC), Mg(2+), NH4(+), Na(+), and K(+)) during the combined 27 months of heating and cooling, suggesting changes in concentration between 4% and 31% for a temperature change of 7 °C.

  5. Water temperature and fish growth: otoliths predict growth patterns of a marine fish in a changing climate.

    PubMed

    Rountrey, Adam N; Coulson, Peter G; Meeuwig, Jessica J; Meekan, Mark

    2014-08-01

    Ecological modeling shows that even small, gradual changes in body size in a fish population can have large effects on natural mortality, biomass, and catch. However, efforts to model the impact of climate change on fish growth have been hampered by a lack of long-term (multidecadal) data needed to understand the effects of temperature on growth rates in natural environments. We used a combination of dendrochronology techniques and additive mixed-effects modeling to examine the sensitivity of growth in a long-lived (up to 70 years), endemic marine fish, the western blue groper (Achoerodus gouldii), to changes in water temperature. A multi-decadal biochronology (1952-2003) of growth was constructed from the otoliths of 56 fish collected off the southwestern coast of Western Australia, and we tested for correlations between the mean index chronology and a range of potential environmental drivers. The chronology was significantly correlated with sea surface temperature in the region, but common variance among individuals was low. This suggests that this species has been relatively insensitive to past variations in climate. Growth increment and age data were also used in an additive mixed model to predict otolith growth and body size later this century. Although growth was relatively insensitive to changes in temperature, the model results suggested that a fish aged 20 in 2099 would have an otolith about 10% larger and a body size about 5% larger than a fish aged 20 in 1977. Our study shows that species or populations regarded as relatively insensitive to climate change could still undergo significant changes in growth rate and body size that are likely to have important effects on the productivity and yield of fisheries.

  6. Marine response to climate changes during the last five millennia in the central Mediterranean Sea

    NASA Astrophysics Data System (ADS)

    Margaritelli, G.; Vallefuoco, M.; Di Rita, F.; Capotondi, L.; Bellucci, L. G.; Insinga, D. D.; Petrosino, P.; Bonomo, S.; Cacho, I.; Cascella, A.; Ferraro, L.; Florindo, F.; Lubritto, C.; Lurcock, P. C.; Magri, D.; Pelosi, N.; Rettori, R.; Lirer, F.

    2016-07-01

    We present a high-resolution paleoclimatic and paleoenvironmental reconstruction of the last five millennia from a shallow water marine sedimentary record from the central Tyrrhenian Sea (Gulf of Gaeta) using planktonic foraminifera, pollen, oxygen stable isotope, tephrostratigrapy and magnetostratigrapy. This multiproxy approach allows to evidence and characterize nine time intervals associated with archaeological/cultural periods: Eneolithic (base of the core-ca. 2410 BCE), Early Bronze Age (ca. 2410 BCE-ca. 1900 BCE), Middle Bronze Age-Iron Age (ca. 1900 BCE-ca. 500 BCE), Roman Period (ca. 500 BCE-ca. 550 CE), Dark Age (ca. 550 CE-ca. 860 CE), Medieval Climate Anomaly (ca. 860 CE-ca. 1250 CE), Little Ice Age (ca. 1250 CE-ca. 1850 CE), Industrial Period (ca. 1850 CE-ca. 1950 CE), Modern Warm Period (ca. 1950 CE-present day). The reconstructed climatic evolution in the investigated sedimentary succession is coherent with the short-term climate variability documented at the Mediterranean scale. By integrating the planktonic foraminiferal turnover from carnivorous to herbivorous-opportunistic species, the oxygen isotope record and the pollen distribution, we document important modification from the onset of the Roman Period to the present-day. From ca. 500 CE upwards the documentation of the cooling trend punctuated by climate variability at secular scale evidenced by the short-term δ18O is very detailed. We hypothesise that the present day warm conditions started from the end of cold Maunder event. Additionally, we provide that the North Atlantic Oscillation (NAO) directly affected the central Mediterranean region during the investigated time interval.

  7. Quantifying Patterns of Change in Marine Ecosystem Response to Multiple Pressures

    PubMed Central

    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

  8. 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

  9. Extensive geographic and ontogenetic variation characterizes the trophic ecology of a temperate reef fish on southern California (USA) rocky reefs

    PubMed Central

    Hamilton, Scott L.; Caselle, Jennifer E.; Lantz, Coulson A.; Egloff, Tiana L.; Kondo, Emi; Newsome, Seth D.; Loke-Smith, Kerri; Pondella, Daniel J.; Young, Kelly A.; Lowe, Christopher G.

    2015-01-01

    Interactions between predator and prey act to shape the structure of ecological communities, and these interactions can differ across space. California sheephead Semicossyphus pulcher are common predators of benthic invertebrates in kelp beds and rocky reefs in southern California, USA. Through gut content and stable isotope (δ13C and †15N) analyses, we investigated geographic and ontogenetic variation in trophic ecology across 9 populations located at island and mainland sites throughout southern California. We found extensive geographic variation in California sheephead diet composition over small spatial scales. Populations differed in the proportion of sessile filter/suspension feeders or mobile invertebrates in the diet. Spatial variation in diet was highly correlated with other life history and demographic traits (e.g. growth, survivorship, reproductive condition, and energy storage), in addition to proxies of prey availability from community surveys. Multivariate descriptions of the diet from gut contents roughly agreed with the spatial groupings of sites based on stable isotope analysis of both California sheephead and their prey. Ontogenetic changes in diet occurred consistently across populations, despite spatial differences in size structure. As California sheephead increase in size, diets shift from small filter feeders, like bivalves, to larger mobile invertebrates, such as sea urchins. Our results indicate that locations with large California sheephead present, such as many marine reserves, may experience increased predation pressure on sea urchins, which could ultimately affect kelp persistence. PMID:26246648

  10. Extensive geographic and ontogenetic variation characterizes the trophic ecology of a temperate reef fish on southern California (USA) rocky reefs.

    PubMed

    Hamilton, Scott L; Caselle, Jennifer E; Lantz, Coulson A; Egloff, Tiana L; Kondo, Emi; Newsome, Seth D; Loke-Smith, Kerri; Pondella, Daniel J; Young, Kelly A; Lowe, Christopher G

    Interactions between predator and prey act to shape the structure of ecological communities, and these interactions can differ across space. California sheephead Semicossyphus pulcher are common predators of benthic invertebrates in kelp beds and rocky reefs in southern California, USA. Through gut content and stable isotope (δ(13)C and †(15)N) analyses, we investigated geographic and ontogenetic variation in trophic ecology across 9 populations located at island and mainland sites throughout southern California. We found extensive geographic variation in California sheephead diet composition over small spatial scales. Populations differed in the proportion of sessile filter/suspension feeders or mobile invertebrates in the diet. Spatial variation in diet was highly correlated with other life history and demographic traits (e.g. growth, survivorship, reproductive condition, and energy storage), in addition to proxies of prey availability from community surveys. Multivariate descriptions of the diet from gut contents roughly agreed with the spatial groupings of sites based on stable isotope analysis of both California sheephead and their prey. Ontogenetic changes in diet occurred consistently across populations, despite spatial differences in size structure. As California sheephead increase in size, diets shift from small filter feeders, like bivalves, to larger mobile invertebrates, such as sea urchins. Our results indicate that locations with large California sheephead present, such as many marine reserves, may experience increased predation pressure on sea urchins, which could ultimately affect kelp persistence.

  11. Endocrine-disrupting chemicals and climate change: A worst-case combination for arctic marine mammals and seabirds?

    PubMed

    Jenssen, Bjørn Munro

    2006-04-01

    The effects of global change on biodiversity and ecosystem functioning encompass multiple complex dynamic processes. Climate change and exposure to endocrine-disrupting chemicals (EDCs) are currently regarded as two of the most serious anthropogenic threats to biodiversity and ecosystems. We should, therefore, be especially concerned about the possible effects of EDCs on the ability of Arctic marine mammals and seabirds to adapt to environmental alterations caused by climate change. Relationships between various organochlorine compounds, necessary suc