Sample records for exploit food resources

  1. Self-organization, collective decision making and resource exploitation strategies in social insects

    NASA Astrophysics Data System (ADS)

    Nicolis, S. C.; Dussutour, A.

    2008-10-01

    Amplifying communications are a ubiquitous characteristic of group-living animals. This work is concerned with their role in the processes of food recruitment and resource exploitation by social insects. The collective choices made by ants faced with different food sources are analyzed using both a mean field description and a stochastic approach. Emphasis is placed on the possibility of optimizing the recruitment and exploitation strategies through an appropriate balance between individual variability, cooperative interactions and environmental constraints.

  2. Apparent foraging success reflects habitat quality in an irruptive species, the Black-backed Woodpecker

    Treesearch

    Christopher T. Rota; Mark A. Rumble; Chad P. Lehman; Dylan C. Kesler; Joshua J. Millspaugh

    2015-01-01

    Dramatic fluctuations in food resources are a key feature of many habitats, and many species have evolved a movement strategy to exploit food resources that are unpredictable in space and time. The availability of food resources may be a particularly strong determinant of habitat quality for irruptive bird species. We studied the apparent foraging success of Black-...

  3. A fish is not a fish: patterns in fatty acid composition of aquatic food may have had implications for hominin evolution.

    PubMed

    Joordens, Josephine C A; Kuipers, Remko S; Wanink, Jan H; Muskiet, Frits A J

    2014-12-01

    From c. 2 Ma (millions of years ago) onwards, hominin brain size and cognition increased in an unprecedented fashion. The exploitation of high-quality food resources, notably from aquatic ecosystems, may have been a facilitator or driver of this phenomenon. The aim of this study is to contribute to the ongoing debate on the possible role of aquatic resources in hominin evolution by providing a more detailed nutritional context. So far, the debate has focused on the relative importance of terrestrial versus aquatic resources while no distinction has been made between different types of aquatic resources. Here we show that Indian Ocean reef fish and eastern African lake fish yield on average similarly high amounts of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid (AA). Hence a shift from exploiting tropical marine to freshwater ecosystems (or vice versa) would entail no material difference in dietary long-chain polyunsaturated fatty acid (LC-PUFA) availability. However, a shift to marine ecosystems would likely mean a major increase in access to brain-selective micronutrients such as iodine. Fatty fish from marine temperate/cold waters yield twice as much DHA and four times as much EPA as tropical fish, demonstrating that a latitudinal shift in exploitation of African coastal ecosystems could constitute a significant difference in LC-PUFA availability with possible implications for brain development and functioning. We conclude that exploitation of aquatic food resources could have facilitated the initial moderate hominin brain increase as observed in fossils dated to c. 2 Ma, but not the exceptional brain increase in later stages of hominin evolution. We propose that the significant expansion in hominin brain size and cognition later on may have been aided by strong directional selecting forces such as runaway sexual selection of intelligence, and nutritionally supported by exploitation of high-quality food resources in stable and productive aquatic ecosystems. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Role of social interactions in dynamic patterns of resource patches and forager aggregation.

    PubMed

    Tania, Nessy; Vanderlei, Ben; Heath, Joel P; Edelstein-Keshet, Leah

    2012-07-10

    The dynamics of resource patches and species that exploit such patches are of interest to ecologists, conservation biologists, modelers, and mathematicians. Here we consider how social interactions can create unique, evolving patterns in space and time. Whereas simple prey taxis (with consumable prey) promotes spatial uniform distributions, here we show that taxis in producer-scrounger groups can lead to pattern formation. We consider two types of foragers: those that search directly ("producers") and those that exploit other foragers to find food ("scroungers" or exploiters). We show that such groups can sustain fluctuating spatiotemporal patterns, akin to "waves of pursuit." Investigating the relative benefits to the individuals, we observed conditions under which either strategy leads to enhanced success, defined as net food consumption. Foragers that search for food directly have an advantage when food patches are localized. Those that seek aggregations of group mates do better when their ability to track group mates exceeds the foragers' food-sensing acuity. When behavioral switching or reproductive success of the strategies is included, the relative abundance of foragers and exploiters is dynamic over time, in contrast with classic models that predict stable frequencies. Our work shows the importance of considering two-way interaction--i.e., how food distribution both influences and is influenced by social foraging and aggregation of predators.

  5. Different responses of congeneric consumers to an exotic food resource: Who gets the novel resource prize?

    Treesearch

    Yvette K. Ortega; Leigh F. Greenwood; Ragan M. Callaway; Dean E. Pearson

    2014-01-01

    Exotic species can provide abundant food resources for native consumers, but predicting which native species will respond positively remains a challenge. We studied the foraging behavior of blackcapped (Poecile atricapillus) andmountain (P. gambeli) chickadees in westernMontana to compare the degree to which these congeric and syntopic consumers exploited larvae of...

  6. Role of social interactions in dynamic patterns of resource patches and forager aggregation

    PubMed Central

    Tania, Nessy; Vanderlei, Ben; Heath, Joel P.; Edelstein-Keshet, Leah

    2012-01-01

    The dynamics of resource patches and species that exploit such patches are of interest to ecologists, conservation biologists, modelers, and mathematicians. Here we consider how social interactions can create unique, evolving patterns in space and time. Whereas simple prey taxis (with consumable prey) promotes spatial uniform distributions, here we show that taxis in producer–scrounger groups can lead to pattern formation. We consider two types of foragers: those that search directly (“producers”) and those that exploit other foragers to find food (“scroungers” or exploiters). We show that such groups can sustain fluctuating spatiotemporal patterns, akin to “waves of pursuit.” Investigating the relative benefits to the individuals, we observed conditions under which either strategy leads to enhanced success, defined as net food consumption. Foragers that search for food directly have an advantage when food patches are localized. Those that seek aggregations of group mates do better when their ability to track group mates exceeds the foragers’ food-sensing acuity. When behavioral switching or reproductive success of the strategies is included, the relative abundance of foragers and exploiters is dynamic over time, in contrast with classic models that predict stable frequencies. Our work shows the importance of considering two-way interaction—i.e., how food distribution both influences and is influenced by social foraging and aggregation of predators. PMID:22745167

  7. Abrupt changes in the patterns and complexity of anterior cingulate cortex activity when food is introduced into an environment

    PubMed Central

    Caracheo, Barak F.; Emberly, Eldon; Hadizadeh, Shirin; Hyman, James M.; Seamans, Jeremy K.

    2013-01-01

    Foraging typically involves two distinct phases, an exploration phase where an organism explores its local environment in search of needed resources and an exploitation phase where a discovered resource is consumed. The behavior and cognitive requirements of exploration and exploitation are quite different and yet organisms can quickly and efficiently switch between them many times during a foraging bout. The present study investigated neural activity state dynamics in the anterior cingulate sub-region of the rat medial prefrontal cortex (mPFC) when a reliable food source was introduced into an environment. Distinct and largely independent states were detected using a Hidden Markov Model (HMM) when food was present or absent in the environment. Measures of neural entropy or complexity decreased when rats went from exploring the environment to exploiting a reliable food source. Exploration in the absence of food was associated with many weak activity states, while bouts of food consumption were characterized by fewer stronger states. Widespread activity state changes in the mPFC may help to inform foraging decisions and focus behavior on what is currently most prominent or valuable in the environment. PMID:23745102

  8. Diel horizontal migration in streams: juvenile fish exploit spatial heterogeneity in thermal and trophic resources

    USGS Publications Warehouse

    Armstrong, Jonathan B.; Schindler, Daniel E.; Ruff, Casey P.; Brooks, Gabriel T.; Bentley, Kale E.; Torgersen, Christian E.

    2013-01-01

    Vertical heterogeneity in the physical characteristics of lakes and oceans is ecologically salient and exploited by a wide range of taxa through diel vertical migration to enhance their growth and survival. Whether analogous behaviors exploit horizontal habitat heterogeneity in streams is largely unknown. We investigated fish movement behavior at daily timescales to explore how individuals integrated across spatial variation in food abundance and water temperature. Juvenile coho salmon made feeding forays into cold habitats with abundant food, and then moved long distances (350–1300 m) to warmer habitats that accelerated their metabolism and increased their assimilative capacity. This behavioral thermoregulation enabled fish to mitigate trade-offs between trophic and thermal resources by exploiting thermal heterogeneity. Fish that exploited thermal heterogeneity grew at substantially faster rates than did individuals that assumed other behaviors. Our results provide empirical support for the importance of thermal diversity in lotic systems, and emphasize the importance of considering interactions between animal behavior and habitat heterogeneity when managing and restoring ecosystems.

  9. European Science Notes Information Bulletin Reports on Current European/Middle Eastern Science

    DTIC Science & Technology

    1990-02-01

    Exploitation and Optimum Use of discussed the relationship of the Framework program to Biological Resources the 1992 single European market. This...operation: Shared-cost contracts]. hancement of food quality; (2) food hygiene, safety, and D. The Exploitation and optimum use or Biological toxicology...Table 9), and dis- bracing the biological sciences, agriculture, geologi- semination of research results (see Table 10). cal, and marine and deep sea

  10. Paleolithic human exploitation of plant foods during the last glacial maximum in North China

    PubMed Central

    Liu, Li; Bestel, Sheahan; Shi, Jinming; Song, Yanhua; Chen, Xingcan

    2013-01-01

    Three grinding stones from Shizitan Locality 14 (ca. 23,000–19,500 calendar years before present) in the middle Yellow River region were subjected to usewear and residue analyses to investigate human adaptation during the last glacial maximum (LGM) period, when resources were generally scarce and plant foods may have become increasingly important in the human diet. The results show that these tools were used to process various plants, including Triticeae and Paniceae grasses, Vigna beans, Dioscorea opposita yam, and Trichosanthes kirilowii snakegourd roots. Tubers were important food resources for Paleolithic hunter–gatherers, and Paniceae grasses were exploited about 12,000 y before their domestication. The long tradition of intensive exploitation of certain types of flora helped Paleolithic people understand the properties of these plants, including their medicinal uses, and eventually led to the plants' domestication. This study sheds light on the deep history of the broad spectrum subsistence strategy characteristic of late Pleistocene north China before the origins of agriculture in this region. PMID:23509257

  11. Paleolithic human exploitation of plant foods during the last glacial maximum in North China.

    PubMed

    Liu, Li; Bestel, Sheahan; Shi, Jinming; Song, Yanhua; Chen, Xingcan

    2013-04-02

    Three grinding stones from Shizitan Locality 14 (ca. 23,000-19,500 calendar years before present) in the middle Yellow River region were subjected to usewear and residue analyses to investigate human adaptation during the last glacial maximum (LGM) period, when resources were generally scarce and plant foods may have become increasingly important in the human diet. The results show that these tools were used to process various plants, including Triticeae and Paniceae grasses, Vigna beans, Dioscorea opposita yam, and Trichosanthes kirilowii snakegourd roots. Tubers were important food resources for Paleolithic hunter-gatherers, and Paniceae grasses were exploited about 12,000 y before their domestication. The long tradition of intensive exploitation of certain types of flora helped Paleolithic people understand the properties of these plants, including their medicinal uses, and eventually led to the plants' domestication. This study sheds light on the deep history of the broad spectrum subsistence strategy characteristic of late Pleistocene north China before the origins of agriculture in this region.

  12. Patterns of resource exploitation in four coexisting globeflower fly species ( Chiastocheta sp.)

    NASA Astrophysics Data System (ADS)

    Pompanon, François; Pettex, Emeline; Després, Laurence

    2006-03-01

    Life history and spatio-temporal patterns of resource utilisation were characterised in four Chiastocheta (Diptera: Anthomyiidae) species, whose larvae compete as seed predators on Trollius europaeus fruits. Interspecific co-occurrence was observed in 80% of the resource patches (= Trollius fruits) in the two communities studied. Isolated larvae from all species had a similar food intake, but differed in development time and size at emergence. Different species exhibit contrasting resource exploitation strategies with specific mining patterns and a partial temporal shift. Two species exhibited particularly singular strategies. C. rotundiventris escaped from strong interactions with other species because it was the first species to develop and the only one to exploit the central pith of Trollius fruits. The key role of this species as the main pollinator of the host-plant appears to be a by-product of constraints imposed by occupying a restricted niche. Although the resource is ephemeral due to seed dispersal, C. dentifera, the last species to oviposit, is not disadvantaged because it has a short development time and rapid food intake. The different patterns can partly explain the stability of Chiastocheta communities, but do not prevent competition to occur at high larval densities.

  13. NUTRIENT ENRICHMENT AND FISHERIES EXPLOITATION: INTERACTIVE EFFECTS ON ESTUARINE LIVING RESOURCES AND THEIR MANAGEMENT

    EPA Science Inventory

    Fisheries exploitation and increased nutrient loadings affect fish and shellfish abudance and production in estuaries. These stressors do not act independently; instead they jointly influence food webs, and each affects the sensitivity of species and ecosystems to the other. Nu...

  14. Redesigning the exploitation of wheat genetic resources.

    PubMed

    Longin, C Friedrich H; Reif, Jochen C

    2014-10-01

    More than half a million wheat genetic resources are resting in gene banks worldwide. Unlocking their hidden favorable genetic diversity for breeding is pivotal for enhancing grain yield potential, and averting future food shortages. Here, we propose exploiting recent advances in hybrid wheat technology to uncover the masked breeding values of wheat genetic resources. The gathered phenotypic information will enable a targeted choice of accessions with high value for pre-breeding among this plethora of genetic resources. We intend to provoke a paradigm shift in pre-breeding strategies for grain yield, moving away from allele mining toward genome-wide selection to bridge the yield gap between genetic resources and elite breeding pools. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Evidence of trapline foraging in honeybees.

    PubMed

    Buatois, Alexis; Lihoreau, Mathieu

    2016-08-15

    Central-place foragers exploiting floral resources often use multi-destination routes (traplines) to maximise their foraging efficiency. Recent studies on bumblebees have showed how solitary foragers can learn traplines, minimising travel costs between multiple replenishing feeding locations. Here we demonstrate a similar routing strategy in the honeybee (Apis mellifera), a major pollinator known to recruit nestmates to discovered food resources. Individual honeybees trained to collect sucrose solution from four artificial flowers arranged within 10 m of the hive location developed repeatable visitation sequences both in the laboratory and in the field. A 10-fold increase of between-flower distances considerably intensified this routing behaviour, with bees establishing more stable and more efficient routes at larger spatial scales. In these advanced social insects, trapline foraging may complement cooperative foraging for exploiting food resources near the hive (where dance recruitment is not used) or when resources are not large enough to sustain multiple foragers at once. © 2016. Published by The Company of Biologists Ltd.

  16. Bust economics: foragers choose high quality habitats in lean times

    PubMed Central

    Dickman, Christopher R.

    2016-01-01

    In environments where food resources are spatially variable and temporarily impoverished, consumers that encounter habitat patches with different food density should focus their foraging initially where food density is highest before they move to patches where food density is lower. Increasing missed opportunity costs should drive individuals progressively to patches with lower food density as resources in the initially high food density patches deplete. To test these expectations, we assessed the foraging decisions of two species of dasyurid marsupials (dunnarts: Sminthopsis hirtipes and S. youngsoni) during a deep drought, or bust period, in the Simpson Desert of central Australia. Dunnarts were allowed access to three patches containing different food densities using an interview chamber experiment. Both species exhibited clear preference for the high density over the lower food density patches as measured in total harvested resources. Similarly, when measuring the proportion of resources harvested within the patches, we observed a marginal preference for patches with initially high densities. Models analyzing behavioral choices at the population level found no differences in behavior between the two species, but models analyzing choices at the individual level uncovered some variation. We conclude that dunnarts can distinguish between habitat patches with different densities of food and preferentially exploit the most valuable. As our observations were made during bust conditions, experiments should be repeated during boom times to assess the foraging economics of dunnarts when environmental resources are high. PMID:26839751

  17. Perception and selection of macrophyte detrital falls by the bathyal echinoid Stylocidaris lineata

    NASA Astrophysics Data System (ADS)

    Young, C. M.; Tyler, P. A.; Emson, R. H.; Gage, J. D.

    1993-07-01

    Many deep-sea animals are known to exploit patchy food resources such as animal carcasses and sunken plant remains, but the mechanisms by which such foods are located remain generally unknown. The bathyal echinoid Stylocidaris lineata is an omnivorous deposit feeder that ingests sediment, dead animal remains, seagrass blades, and macroalgae such as Sargassum spp. Using a submersible, we investigated the ability of urchins to locate and exploit large falls of detritus. Individuals quickly arrived at packets of Thalassia testudinum and Sargassum spp. placed on the bottom, and they preferred these food items significantly over inert controls. However, the echinoids demonstrated no significant tendency to move toward the scent of upstream T. testudinum, either in situ or in laboratory flume experiments. Individuals moved at net speeds up to 30 m day -1. The existing evidence suggests that S. lineata locate food by chance encounter, not distant chemoreception.

  18. Effects of habitat composition on the use of resources by the red fox in a semi arid environment of North Africa

    NASA Astrophysics Data System (ADS)

    Dell'Arte, Graziella L.; Leonardi, Giovanni

    2005-09-01

    The red fox Vulpes vulpes is considered an opportunistic predator able to avoid prey shortages by exploiting a wide range of available food resources. However, as predicted by the Resources Dispersion Hypothesis (RDH), the distribution of other key resources such as suitable areas for dens can affect fox populations. Furthermore, in insularity conditions, resources are spatially limited and their availability is greatly influenced by territory sizes and the feeding habits of predators. In this paper we report the spatial use and foraging habits of foxes in three habitats (grassland, cultivation and suburban) of a sub-arid island off north Africa in relation to habitat composition and food availability. We found that diet composition in a gross sense did not differ significantly among habitats, with insects comprising > 48% and fruits 25% of the total prey items. Grasslands offered temporary clumped food resources (e.g. birds) that induced foxes to increase their territory sizes and to enlarge their diet range during prey shortages. Inversely, in cultivated and suburban areas, the main prey (insects) were more evenly distributed, especially in olive groves which constitute the most extensive form of cultivation on the island. In large areas covered by olive trees, the high availability of Coleoptera spp. significantly reduced core areas used by foxes and also distances among dens. Palm groves were patchy on the island but contained high densities of Orthoptera spp. and date fruits which represent alternative food sources. Thus, these patches are attractive foraging places, but a modification of the perimeter of fox territories was necessary for their exploitation. Our study confirmed that in this arid environment, habitat composition per se affected a generalist predator less than the dispersion of its main prey. In addition, the patchy distribution of resources can assume a role in the spacing and feeding behaviours of foxes only in relation to clumped alternative prey types.

  19. Extreme behavioural shifts by baboons exploiting risky, resource-rich, human-modified environments.

    PubMed

    Fehlmann, Gaelle; O'Riain, M Justin; Kerr-Smith, Catherine; Hailes, Stephen; Luckman, Adrian; Shepard, Emily L C; King, Andrew J

    2017-11-08

    A range of species exploit anthropogenic food resources in behaviour known as 'raiding'. Such behavioural flexibility is considered a central component of a species' ability to cope with human-induced environmental changes. Here, we study the behavioural processes by which raiding male chacma baboons (Papio ursinus) exploit the opportunities and mitigate the risks presented by raiding in the suburbs of Cape Town, South Africa. Ecological sampling and interviews conducted with 'rangers' (employed to manage the baboons' space use) revealed that baboons are at risk of being herded out of urban spaces that contain high-energy anthropogenic food sources. Baboon-attached motion/GPS tracking collars showed that raiding male baboons spent almost all of their time at the urban edge, engaging in short, high-activity forays into the urban space. Moreover, activity levels were increased where the likelihood of deterrence by rangers was greater. Overall, these raiding baboons display a time-activity balance that is drastically altered in comparison to individuals living in more remote regions. We suggest our methods can be used to obtain precise estimates of management impact for this and other species in conflict with people.

  20. [Evaluation of resource exploitation value and ecosystem service loss in Mentougou District of Beijing City].

    PubMed

    Liu, Xu-Sheng; Li, Feng; Zhao, Dan; Wang, Bei-Bei

    2009-06-01

    By using the evaluation approach of ecosystem services (including market value, opportunity cost, restoration cost, and shadow project approaches), and combining with situation investigation, the ecosystem service loss in Mentougou District of Beijing City caused by coal resource exploitation in 1949-2006 was systematically evaluated. In the study area, coal mining mainly induced the cost increase of solid waste disposal and sink reclamation, and the losses in food production, water self-preserving, residents moving, and water and soil resources. The ecosystem service loss caused by the coal mining in 1949-2006 was about 54.3 billion Yuan RMB, approximately 9 times high of its market economic benefit (5.9 billion Yuan RMB). It was very difficult or needed a long time to restore the damaged ecosystem.

  1. ELIXIR pilot action: Marine metagenomics - towards a domain specific set of sustainable services.

    PubMed

    Robertsen, Espen Mikal; Denise, Hubert; Mitchell, Alex; Finn, Robert D; Bongo, Lars Ailo; Willassen, Nils Peder

    2017-01-01

    Metagenomics, the study of genetic material recovered directly from environmental samples, has the potential to provide insight into the structure and function of heterogeneous microbial communities.  There has been an increased use of metagenomics to discover and understand the diverse biosynthetic capacities of marine microbes, thereby allowing them to be exploited for industrial, food, and health care products. This ELIXIR pilot action was motivated by the need to establish dedicated data resources and harmonized metagenomics pipelines for the marine domain, in order to enhance the exploration and exploitation of marine genetic resources. In this paper, we summarize some of the results from the ELIXIR pilot action "Marine metagenomics - towards user centric services".

  2. Reduction of potential food interference in two sympatric carnivores by sequential use of shared resources

    NASA Astrophysics Data System (ADS)

    Barrientos, Rafael; Virgós, Emilio

    2006-07-01

    The common genet ( Genetta genetta) and the stone marten ( Martes foina) are two species that overlap extensively in their distribution ranges in southwest Europe. Available diet data from these species allow us to predict some interference competition for food resources in sympatric populations. We checked the food interference hypothesis in a sympatric population. The diet of both predators was analyzed through scat collection. Seasonal differences in biomass consumption were compared between both species in those items considered as key resources according to biomass consumption. Strawberry tree fruits can be considered as key resource exclusively for genets whereas fungi, blackberries and rabbits are keys for stone martens only. For other key resources consumed by both species (wood mouse and figs) we suggest that a possible mechanism to reduce diet overlap could be the sequential use of these resources: no intensive exploitation by both species of the same key resource during the same season was detected. Figs and wood mouse were used alternatively. Although strawberry tree fruits and blackberry are exclusive key resources of one of the species, their consumptions showed the same pattern. Diet niche overlap in our study is low compared with other carnivore communities suggesting that exclusive use of some key resources and sequential use of shared ones is an optimal scenario to reduce overall competition for food resources.

  3. Testing MacArthur's minimisation principle: do communities minimise energy wastage during succession?

    PubMed

    Ghedini, Giulia; Loreau, Michel; White, Craig R; Marshall, Dustin J

    2018-05-20

    Robert MacArthur developed a theory of community assembly based on competition. By incorporating energy flow, MacArthur's theory allows for predictions of community function. A key prediction is that communities minimise energy wastage over time, but this minimisation is a trade-off between two conflicting processes: exploiting food resources, and maintaining low metabolism and mortality. Despite its simplicity and elegance, MacArthur's principle has not been tested empirically despite having long fascinated theoreticians. We used a combination of field chronosequence experiments and laboratory assays to estimate how the energy wastage of a community changes during succession. We found that older successional stages wasted more energy in maintenance, but there was no clear pattern in how communities of different age exploited food resources. We identify several reasons for why MacArthur's original theory may need modification and new avenues to further explore community efficiency, an understudied component of ecosystem functioning. © 2018 John Wiley & Sons Ltd/CNRS.

  4. Bioprospecting Marine Plankton

    PubMed Central

    Abida, Heni; Ruchaud, Sandrine; Rios, Laurent; Humeau, Anne; Probert, Ian; De Vargas, Colomban; Bach, Stéphane; Bowler, Chris

    2013-01-01

    The ocean dominates the surface of our planet and plays a major role in regulating the biosphere. For example, the microscopic photosynthetic organisms living within provide 50% of the oxygen we breathe, and much of our food and mineral resources are extracted from the ocean. In a time of ecological crisis and major changes in our society, it is essential to turn our attention towards the sea to find additional solutions for a sustainable future. Remarkably, while we are overexploiting many marine resources, particularly the fisheries, the planktonic compartment composed of zooplankton, phytoplankton, bacteria and viruses, represents 95% of marine biomass and yet the extent of its diversity remains largely unknown and underexploited. Consequently, the potential of plankton as a bioresource for humanity is largely untapped. Due to their diverse evolutionary backgrounds, planktonic organisms offer immense opportunities: new resources for medicine, cosmetics and food, renewable energy, and long-term solutions to mitigate climate change. Research programs aiming to exploit culture collections of marine micro-organisms as well as to prospect the huge resources of marine planktonic biodiversity in the oceans are now underway, and several bioactive extracts and purified compounds have already been identified. This review will survey and assess the current state-of-the-art and will propose methodologies to better exploit the potential of marine plankton for drug discovery and for dermocosmetics. PMID:24240981

  5. Rehabilitating mussel beds in Coffee Bay, South Africa: Towards fostering cooperative small-scale fisheries governance and enabling community upliftment.

    PubMed

    Calvo-Ugarteburu, Gurutze; Raemaekers, Serge; Halling, Christina

    2017-03-01

    Along the coast of South Africa, marine resources play a significant role in supporting livelihoods and contributing to food security in impoverished rural communities. Post-apartheid fisheries laws and policies have begun to address traditional fishing rights and development needs, and new management arrangements are being implemented. One such initiative has been the Mussel Rehabilitation Project in Coffee Bay, which piloted a resource rehabilitation technique at several over-exploited fishing sites. Mussel stocks in these exploited areas had dropped to under 1 % mussel cover, and during the project period, stocks increased to >80 % cover, supporting a sustainable harvest well above national daily bag limits. This stock enhancement was achieved only after the project had started to address social challenges such as the lack of local management institutions and the need to enhance food security. The project embarked on training and institution-building; it formed a robust community mussel management committee; and developed a local resource management plan, facilitating increased community participation in the day-to-day management of the resource. The project also saw the initiation of various ancillary projects aimed at improving food security and stimulating the local economy and hence alleviating pressure on the marine resources. Here we review this 10-year project's outcomes, and present lessons for small-scale fisheries governance in South Africa and internationally. We show, through empirical experience, that balancing stock rebuilding needs in a context of widespread poverty and dependency on natural resources by a local fisher community can only be addressed through an integrated approach to development. Participation of resource users and a thorough understanding of the local context are imperative to negotiating appropriate small-scale fisheries governance approaches. We recommend that the implementation of South Africa's newly minted Small-Scale Fisheries Policy should begin with bottom-up, demonstrative resource management measures such as mussel rehabilitation. This type of initiative can deliver short-term food security benefits and foster social learning towards sustainable and cooperative fisheries governance.

  6. Trading off natural resources and rural livelihoods. A framework for sustainability assessment of small-scale food production in water-limited regions

    NASA Astrophysics Data System (ADS)

    Recanati, Francesca; Castelletti, Andrea; Dotelli, Giovanni; Melià, Paco

    2017-12-01

    Enhancing local production is key to promoting food security, especially in rural households of low-income countries, but may conflict with limited natural resources and ecosystems preservation. We propose a framework integrating the water-food nexus and a sustainable livelihoods perspective to assess small-scale food production in water-poor regions. We demonstrate it by assessing alternative production scenarios in the Gaza Strip at different spatial scales. At the scale of a single farm, there is a clear conflict among objectives: while cash crops ensure good incomes but contribute scarcely to domestic protein supply, crops performing well from the nutritional and environmental viewpoint are among the worst from the economic one. At the regional scale, domestic production might cover an important fraction of nutritional needs while contributing to household income, but water scarcity impairs the satisfaction of food demand by domestic production alone. Pursuing food security under multiple constraints thus requires a holistic perspective: we discuss how a multidimensional approach can promote the engagement of different stakeholders and allow the exploration of trade-offs between food security, sustainable exploitation of natural resources and economic viability.

  7. Bat guilds, a concept to classify the highly diverse foraging and echolocation behaviors of microchiropteran bats

    PubMed Central

    Denzinger, Annette; Schnitzler, Hans-Ulrich

    2013-01-01

    Throughout evolution the foraging and echolocation behaviors as well as the motor systems of bats have been adapted to the tasks they have to perform while searching and acquiring food. When bats exploit the same class of environmental resources in a similar way, they perform comparable tasks and thus share similar adaptations independent of their phylogeny. Species with similar adaptations are assigned to guilds or functional groups. Habitat type and foraging mode mainly determine the foraging tasks and thus the adaptations of bats. Therefore, we use habitat type and foraging mode to define seven guilds. The habitat types open, edge and narrow space are defined according to the bats' echolocation behavior in relation to the distance between bat and background or food item and background. Bats foraging in the aerial, trawling, flutter detecting, or active gleaning mode use only echolocation to acquire their food. When foraging in the passive gleaning mode bats do not use echolocation but rely on sensory cues from the food item to find it. Bat communities often comprise large numbers of species with a high diversity in foraging areas, foraging modes, and diets. The assignment of species living under similar constraints into guilds identifies patterns of community structure and helps to understand the factors that underlie the organization of highly diverse bat communities. Bat species from different guilds do not compete for food as they differ in their foraging behavior and in the environmental resources they use. However, sympatric living species belonging to the same guild often exploit the same class of resources. To avoid competition they should differ in their niche dimensions. The fine grain structure of bat communities below the rather coarse classification into guilds is determined by mechanisms that result in niche partitioning. PMID:23840190

  8. The Water-Energy-Food Nexus in a Rapidly Developing Resource Sector

    NASA Astrophysics Data System (ADS)

    Allen, D. M.; Kirste, D. M.

    2014-12-01

    Technological advances and access to global markets have changed the rate at which resource exploitation takes place. The environmental impact of the rapid development and distribution of resources such as minerals and hydrocarbons has led to a greater potential for significant stress on water resources both in terms of quality and quantity. How and where those impacts manifest is crucial to determining appropriate risk management strategies. North East British Columbia has an abundance of shale gas reserves that are anticipated to be exploited at a large scale in coming years, primarily for export as liquefied natural gas (LNG). However, there is growing concern that fracking and other activities related to shale gas development pose risks to water quality and quantity in the region. Water lies at the center of the water-energy-food nexus, with an accelerating water demand for fracking and industrial operations as well as for domestic, environmental and agricultural uses. Climate change is also anticipated to alter the hydrologic regime, posing added stress to the water resource. This case study examines the water-energy-food nexus in the context of a region that is impacted by a rapidly developing resource sector, encompassing water demand/supply, climate change, interaction between deep aquifers and shallow aquifers/surface waters, water quality concerns related to fracking, land use disturbance, and community impacts. Due to the rapid rate of development, there are significant knowledge gaps in our understanding of the water resource. Currently agencies are undertaking water resource assessments and establishing monitoring sites. This research aims to assess water security in North East British Columbia in a coordinated fashion through various partnerships. In addition to collecting baseline knowledge and data, the study will evaluate risk and resilience indicators in relation to water security. A risk assessment framework specific to the shale gas development context will be developed to evaluate the various components of risk spatially and temporally. Resilience is currently being assessed through a comprehensive examination of the current regulatory and policy regime.

  9. Omnivory of an Insular Lizard: Sources of Variation in the Diet of Podarcis lilfordi (Squamata, Lacertidae).

    PubMed

    Pérez-Cembranos, Ana; León, Alicia; Pérez-Mellado, Valentín

    2016-01-01

    Through 17 years and from a sample of 7,790 faecal pellets and 26,346 prey items, we studied the diet of the Balearic lizard Podarcis lilfordi in Aire Island (Menorca, Balearic Islands, Spain). We analysed the diet in terms of prey frequencies, as well as by their volume and biomass contributions. The diet of the Balearic lizard was extremely variable through the years, months and areas under study. The dominance of small clumped prey, particularly ants, was confirmed. However, the main contribution by volume corresponded to beetles, with a relevant role for Diplopoda and terrestrial Isopoda during some months and at particular areas of the island. Several prey items were probably captured at the base of shrubs, under stones or inside rock crevices. Therefore, our estimations of electivity would only be reliable for epigeal and flying prey. The capacity of the Balearic lizard to include marine subsidies in its diet, such as coastal crustaceans, is noteworthy. Also, its consumption of carrion from carcasses of gulls and rabbits and leftovers from human visitors is remarkable. Juvenile conspecifics can also be a sporadic food resource, especially during the second half of summer, whereas the consumption of vegetal matter is constant for each whole year. The shifts of vegetal exploitation among areas of the island and months take place according to availability of different plant species at each area or during a given period. Thus, lizards are able to conduct a thorough monitoring of plant phenology, exploiting a large variety of plant species. Omnivory does not imply the indiscriminate inclusion of any edible food in its diet. Rather, the inclusion of several food items means the adoption of a wide range of foraging behaviours adapted to the exploitation of each food resource.

  10. Omnivory of an Insular Lizard: Sources of Variation in the Diet of Podarcis lilfordi (Squamata, Lacertidae)

    PubMed Central

    Pérez-Cembranos, Ana; León, Alicia; Pérez-Mellado, Valentín

    2016-01-01

    Through 17 years and from a sample of 7,790 faecal pellets and 26,346 prey items, we studied the diet of the Balearic lizard Podarcis lilfordi in Aire Island (Menorca, Balearic Islands, Spain). We analysed the diet in terms of prey frequencies, as well as by their volume and biomass contributions. The diet of the Balearic lizard was extremely variable through the years, months and areas under study. The dominance of small clumped prey, particularly ants, was confirmed. However, the main contribution by volume corresponded to beetles, with a relevant role for Diplopoda and terrestrial Isopoda during some months and at particular areas of the island. Several prey items were probably captured at the base of shrubs, under stones or inside rock crevices. Therefore, our estimations of electivity would only be reliable for epigeal and flying prey. The capacity of the Balearic lizard to include marine subsidies in its diet, such as coastal crustaceans, is noteworthy. Also, its consumption of carrion from carcasses of gulls and rabbits and leftovers from human visitors is remarkable. Juvenile conspecifics can also be a sporadic food resource, especially during the second half of summer, whereas the consumption of vegetal matter is constant for each whole year. The shifts of vegetal exploitation among areas of the island and months take place according to availability of different plant species at each area or during a given period. Thus, lizards are able to conduct a thorough monitoring of plant phenology, exploiting a large variety of plant species. Omnivory does not imply the indiscriminate inclusion of any edible food in its diet. Rather, the inclusion of several food items means the adoption of a wide range of foraging behaviours adapted to the exploitation of each food resource. PMID:26871439

  11. Sex and species specific isotopic niche specialisation increases with trophic complexity: evidence from an ephemeral pond ecosystem

    PubMed Central

    Dalu, Tatenda; Wasserman, Ryan J.; Vink, Tim J. F.; Weyl, Olaf L. F.

    2017-01-01

    It is generally accepted that organisms that naturally exploit an ecosystem facilitate coexistence, at least partially, through resource partitioning. Resource availability is, however, highly variable in space and time and as such the extent of resource partitioning must be somewhat dependent on availability. Here we test aspects of resource partitioning at the inter- and intra-specific level, in relation to resource availability in an atypical aquatic environment using an isotope approach. Using closely related key organisms from an ephemeral pond, we test for differences in isotopic signatures between two species of copepod and between sexes within each species, in relation to heterogeneity of basal food resources over the course of the ponds hydroperiod. We show that basal food resource heterogeneity increases over time initially, and then decreases towards the end of the hydroperiod, reflective of the expected evolution of trophic complexity for these systems. Resource partitioning also varied between species and sexes, over the hydroperiod with intra- and inter-specific specialisation relating to resource availability. Intra-specific specialisation was particularly evident in the omnivorous copepod species. Our findings imply that trophic specialisation at both the intra- and inter-specific level is partly driven by basal food resource availability. PMID:28233858

  12. From Outsourcing to Alliances: Strategies for Sharing Leadership and Exploiting Resources at Metropolitan Universities.

    ERIC Educational Resources Information Center

    Ender, Kenneth L.; Mooney, Kathleen A.

    1994-01-01

    University partnerships with private industry to effect service delivery in facilities management, food services, bookstore management, parking management, arena management, housing operations, business services, safety operations, communication services, and purchasing improves the quality of these services, reduces costs, does not affect core…

  13. The meaning of functional trait composition of food webs for ecosystem functioning.

    PubMed

    Gravel, Dominique; Albouy, Camille; Thuiller, Wilfried

    2016-05-19

    There is a growing interest in using trait-based approaches to characterize the functional structure of animal communities. Quantitative methods have been derived mostly for plant ecology, but it is now common to characterize the functional composition of various systems such as soils, coral reefs, pelagic food webs or terrestrial vertebrate communities. With the ever-increasing availability of distribution and trait data, a quantitative method to represent the different roles of animals in a community promise to find generalities that will facilitate cross-system comparisons. There is, however, currently no theory relating the functional composition of food webs to their dynamics and properties. The intuitive interpretation that more functional diversity leads to higher resource exploitation and better ecosystem functioning was brought from plant ecology and does not apply readily to food webs. Here we appraise whether there are interpretable metrics to describe the functional composition of food webs that could foster a better understanding of their structure and functioning. We first distinguish the various roles that traits have on food web topology, resource extraction (bottom-up effects), trophic regulation (top-down effects), and the ability to keep energy and materials within the community. We then discuss positive effects of functional trait diversity on food webs, such as niche construction and bottom-up effects. We follow with a discussion on the negative effects of functional diversity, such as enhanced competition (both exploitation and apparent) and top-down control. Our review reveals that most of our current understanding of the impact of functional trait diversity on food web properties and functioning comes from an over-simplistic representation of network structure with well-defined levels. We, therefore, conclude with propositions for new research avenues for both theoreticians and empiricists. © 2016 The Author(s).

  14. The meaning of functional trait composition of food webs for ecosystem functioning

    PubMed Central

    Albouy, Camille

    2016-01-01

    There is a growing interest in using trait-based approaches to characterize the functional structure of animal communities. Quantitative methods have been derived mostly for plant ecology, but it is now common to characterize the functional composition of various systems such as soils, coral reefs, pelagic food webs or terrestrial vertebrate communities. With the ever-increasing availability of distribution and trait data, a quantitative method to represent the different roles of animals in a community promise to find generalities that will facilitate cross-system comparisons. There is, however, currently no theory relating the functional composition of food webs to their dynamics and properties. The intuitive interpretation that more functional diversity leads to higher resource exploitation and better ecosystem functioning was brought from plant ecology and does not apply readily to food webs. Here we appraise whether there are interpretable metrics to describe the functional composition of food webs that could foster a better understanding of their structure and functioning. We first distinguish the various roles that traits have on food web topology, resource extraction (bottom-up effects), trophic regulation (top-down effects), and the ability to keep energy and materials within the community. We then discuss positive effects of functional trait diversity on food webs, such as niche construction and bottom-up effects. We follow with a discussion on the negative effects of functional diversity, such as enhanced competition (both exploitation and apparent) and top-down control. Our review reveals that most of our current understanding of the impact of functional trait diversity on food web properties and functioning comes from an over-simplistic representation of network structure with well-defined levels. We, therefore, conclude with propositions for new research avenues for both theoreticians and empiricists. PMID:27114571

  15. ELIXIR pilot action: Marine metagenomics – towards a domain specific set of sustainable services

    PubMed Central

    Robertsen, Espen Mikal; Denise, Hubert; Mitchell, Alex; Finn, Robert D.; Bongo, Lars Ailo; Willassen, Nils Peder

    2017-01-01

    Metagenomics, the study of genetic material recovered directly from environmental samples, has the potential to provide insight into the structure and function of heterogeneous microbial communities.  There has been an increased use of metagenomics to discover and understand the diverse biosynthetic capacities of marine microbes, thereby allowing them to be exploited for industrial, food, and health care products. This ELIXIR pilot action was motivated by the need to establish dedicated data resources and harmonized metagenomics pipelines for the marine domain, in order to enhance the exploration and exploitation of marine genetic resources. In this paper, we summarize some of the results from the ELIXIR pilot action “Marine metagenomics – towards user centric services”. PMID:28620454

  16. Spider monkey ranging patterns in Mexican subtropical forest: do travel routes reflect planning?

    PubMed

    Valero, Alejandra; Byrne, Richard W

    2007-07-01

    Although it is well known that frugivorous spider monkeys (Ateles geoffroyi yucatanensis) occupy large home ranges, travelling long distances to reach highly productive resources, little is known of how they move between feeding sites. A 11 month study of spider monkey ranging patterns was carried out at the Otochma'ax Yetel Kooh reserve, Yucatán, Mexico. We followed single individuals for as long as possible each day and recorded the routes travelled with the help of a GPS (Global Positioning System) device; the 11 independently moving individuals of a group were targeted as focal subjects. Travel paths were composed of highly linear segments, each typically ending at a place where some resource was exploited. Linearity of segments did not differ between individuals, and most of the highly linear paths that led to food resources were much longer than the estimate visibility in the woodland canopy. Monkeys do not generally continue in the same ranging direction after exploiting a resource: travel paths are likely to deviate at the site of resource exploitation rather than between such sites. However, during the harshest months of the year consecutive route segments were more likely to retain the same direction of overall movement. Together, these findings suggest that while moving between feeding sites, spider monkeys use spatial memory to guide travel, and even plan more than one resource site in advance.

  17. Cocoa based agroforestry: An economic perspective in resource scarcity conflict era

    NASA Astrophysics Data System (ADS)

    Jumiyati, S.; Arsyad, M.; Rajindra; Pulubuhu, D. A. T.; Hadid, A.

    2018-05-01

    Agricultural development towards food self-sufficiency based on increasing production alone has caused the occurrence of environmental disasters that are the impact of the exploitation of natural resources resulting in the scarcity of resources. This paper describes the optimization of land area, revenue, cost (production inputs), income and use of production input based on economic and ecological aspects. In order to sustainability farming by integrating environmental and economic consideration can be made through farmers’ decision making with the goal of optimizing revenue based on cost optimization through cocoa based agroforestry model in order to cope with a resource conflict resolution.

  18. Yellowjackets use nest-based cues to differentially exploit higher-quality resources

    NASA Astrophysics Data System (ADS)

    Taylor, Benjamin J.; Schalk, Dane R.; Jeanne, Robert L.

    2010-12-01

    While foraging, social insects encounter a dynamic array of food resources of varying quality and profitability. Because food acquisition influences colony growth and fitness, natural selection can be expected to favor colonies that allocate their overall foraging effort so as to maximize their intake of high-quality nutrients. Social wasps lack recruitment communication, but previous studies of vespine wasps have shown that olfactory cues influence foraging decisions. Odors associated with food brought into the nest by successful foragers prompt naive foragers to leave the nest and search for the source of those odors. Left unanswered, however, is the question of whether naive foragers take food quality into account in making their decisions about whether or not to search. In this study, two different concentrations of sucrose solutions, scented differently, were inserted directly into each of three Vespula germanica nests. At a feeder away from the nest, arriving foragers were given a choice between two 1.5 M sucrose solutions with the same scents as those in the nest. We show that wasps chose higher-quality resources in the field using information in the form of intranidal food-associated odor cues. By this simple mechanism, the colony can bias the allocation of its foraging effort toward higher-quality resources in the environment.

  19. Biomass transformation webs provide a unified approach to consumer–resource modelling

    PubMed Central

    Getz, Wayne M.

    2011-01-01

    An approach to modelling food web biomass flows among live and dead compartments within and among species is formulated using metaphysiological principles that characterise population growth in terms of basal metabolism, feeding, senescence and exploitation. This leads to a unified approach to modelling interactions among plants, herbivores, carnivores, scavengers, parasites and their resources. Also, dichotomising sessile miners from mobile gatherers of resources, with relevance to feeding and starvation time scales, suggests a new classification scheme involving 10 primary categories of consumer types. These types, in various combinations, rigorously distinguish scavenger from parasite, herbivory from phytophagy and detritivore from decomposer. Application of the approach to particular consumer–resource interactions is demonstrated, culminating in the construction of an anthrax-centred food web model, with parameters applicable to Etosha National Park, Namibia, where deaths of elephants and zebra from the bacterial pathogen, Bacillus anthracis, provide significant subsidies to jackals, vultures and other scavengers. PMID:21199247

  20. Modelling the water-agricultural sector in Rosetta, Egypt: exploring the interaction between water and food

    NASA Astrophysics Data System (ADS)

    Sušnik, Janez; Vamvakeridou-Lyroudia, Lydia; Savic, Dragan; Kapelan, Zoran

    2014-05-01

    An integrated System Dynamics Model for the Rosetta region, Egypt, assessing local water balance and agricultural yield to 2050, is presented. Fifty-seven simulations are analysed to better understand potential impacts on water and food security resulting from climate and social change and local/regional policy decisions related to the agricultural sector. Water limitation is a national issue: Egypt relies on the Nile for >95% of supply, and the flow of which is regulated by the Aswan High Dam. Egypt's share water of Aswan water is limited to 55 x 19 m3 yr-1. Any reduction in supply to the reservoir or increase in demand (e.g. from an expanding agricultural sector), has the potential to lead to a serious food and water supply situation. Results show current water resource over-exploitation. The remaining suite of 56 simulations, divided into seven scenarios, also mostly show resource overexploitation. Only under significant increases to Nile flow volumes was the trend reversed. Despite this, by threading together multiple local policies to reduce demand and improve/maintain supply, water resource exploitation can be mitigated while allowing for agricultural development. By changing cropping patterns, it is possible to improve yield and revenue, while using up to 21% less water in 2050 when compared with today. The results are useful in highlighting pathways to improving future water resource availability. Many policies should be considered in parallel, introducing redundancy into the policy framework. We do not suggest actual policy measures; this was beyond the scope of the work. This work highlights the utility of systems modelling of complex systems such as the water-food nexus, with the potential to extend the methodology to other studies and scales. In particular, the benefit of being able to easily modify and extend existing models in light of results from initial modelling efforts is cited. Analysis of initial results led to the hypothesis that by producing excess crop as a result of cropping pattern changes, international markets could be exploited, leading to further local improvements to the water balance, food yield and revenue. An extension 'module' was added onto the initial model which aimed to simulate this exploitation of international markets. Despite the promising results, any improvements would probably manifest after a number of years, have to be managed carefully, and would increase reliance on other countries, something that would need to be considered at the national level. It would also be prudent to implement such a policy in parallel with others aimed at mitigating potential future drought scenarios. This work was part of EC FP7 'WASSERMed' (Water Availability and Security in Southern EuRope and the Mediterranean) project analysing current and future climate-induced changes to hydrological budgets and extremes throughout the Mediterranean basin under the frame of threats to national and human security.

  1. The recruiter's excitement--features of thoracic vibrations during the honey bee's waggle dance related to food source profitability.

    PubMed

    Hrncir, Michael; Maia-Silva, Camila; Mc Cabe, Sofia I; Farina, Walter M

    2011-12-01

    The honey bee's waggle dance constitutes a remarkable example of an efficient code allowing social exploitation of available feeding sites. In addition to indicating the position (distance, direction) of a food patch, both the occurrence and frequency of the dances depend on the profitability of the exploited resource (sugar concentration, solution flow rate). During the waggle dance, successful foragers generate pulsed thoracic vibrations that putatively serve as a source of different kinds of information for hive bees, who cannot visually decode dances in the darkness of the hive. In the present study, we asked whether these vibrations are a reliable estimator of the excitement of the dancer when food profitability changes in terms of both sugar concentration and solution flow rate. The probability of producing thoracic vibrations as well as several features related to their intensity during the waggle phase (pulse duration, velocity amplitude, duty cycle) increased with both these profitability variables. The number of vibratory pulses, however, was independent of sugar concentration and reward rate exploited. Thus, pulse number could indeed be used by dance followers as reliable information about food source distance, as suggested in previous studies. The variability of the dancer's thoracic vibrations in relation to changes in food profitability suggests their role as an indicator of the recruiter's motivational state. Hence, the vibrations could make an important contribution to forager reactivation and, consequently, to the organisation of collective foraging processes in honey bees.

  2. The early bird gets the worm: foraging strategies of wild songbirds lead to the early discovery of food sources

    PubMed Central

    Farine, Damien R.; Lang, Stephen D. J.

    2013-01-01

    Animals need to manage the combined risks of predation and starvation in order to survive. Theoretical and empirical studies have shown that individuals can reduce predation risk by delaying feeding (and hence fat storage) until late afternoon. However, little is known about how individuals manage the opposing pressures of resource uncertainty and predation risks. We suggest that individuals should follow a two-part strategy: prioritizing the discovery of food early in the day and exploiting the best patch late in the day. Using automated data loggers, we tested whether a temporal component exists in the discovery of novel foraging locations by individuals in a mixed-species foraging guild. We found that food deployed in the morning was discovered significantly more often than food deployed in the afternoon. Based on the diurnal activity patterns in this population, overall rates of new arrivals were also significantly higher than expected in the morning and significantly lower than expected in the afternoon. These results align with our predictions of a shift from patch discovery to exploitation over the course of the day. PMID:24108676

  3. Estuarine resources use by juvenile Flagfin mojarra ( Eucinostomus melanopterus) in an inverse tropical estuary (Sine Saloum, Senegal)

    NASA Astrophysics Data System (ADS)

    Gning, Ndombour; Le Loc'h, François; Thiaw, Omar T.; Aliaume, Catherine; Vidy, Guy

    2010-03-01

    The Flagfin mojarra, Eucinostomus melanopterus, is a marine spawner whose young individuals are common in the Sine Saloum inverse estuary (Senegal). The species offers the opportunity to study both the use of the estuarine nursery resources and the impact of the particular environment of the inverse estuary on these resources. This will lead to a better understanding of the functioning of the nursery. We investigated the resources used by juvenile Flagfin mojarra by coupling stomach contents and stable isotopes methods. Young Flagfin mojarra feed on a wide range of invertebrates. Diet changed from copepods in the smallest size class (10-40 mm), to a range of invertebrates including amphipods, insect larvae, polychaetes and mollusc in the medium size class (up to 60 mm) and mainly polychaetes for individuals >60 mm in size. In mangrove habitats with moderate salinity, the diet was dominated by polychaetes and decapod larvae (crabs) whereas in habitats with higher salinity, diet was dominated by amphipods. In very hypersaline areas with scarce mangroves, diet comprised benthic copepods, chironomid larvae and ostracods. This agreed with a clear change in δ13C measured in fish sampled at downstream or upstream sites. Comparison with signatures of primary producers suggested that the local food web exploited by young Flagfin mojarra is mainly based on phytoplankton in the downstream mangrove area, and mainly on benthic microalgae in the upstream hypersaline area. As in many studies considering the food webs in mangrove, mangrove was not identified as a major contributor to the food web exploited by E. melanopterus. This needs further investigation particularly because the exportation of estuarine materials to the sea is limited in an inverse estuary.

  4. Attraction to Carbon Dioxide from Feeding Resources and Conspecific Neighbours in Larvae of the Rhinoceros Beetle Trypoxylus dichotomus

    PubMed Central

    Kojima, Wataru

    2015-01-01

    Saprophagous (feeding on decaying matter) insects often use carbon dioxide (CO2) as a cue for finding food. Humus-feeding larvae of the giant rhinoceros beetle Trypoxylus dichotomus exhibit a clumped distribution in natural microhabitats, but the mechanisms driving the distribution were unknown. Herein, I examined whether larvae use CO2 as a cue for fermented humus and aggregate in the vicinity of the food. I found that (i) larvae of T. dichotomus are strongly attracted to CO2, (ii) larvae orient toward highly fermented humus when given a choice between highly and poorly fermented humus, (iii) the highly fermented humus emits more CO2 than the poorly fermented humus, and (iv) larvae grow larger when fed highly fermented humus rather than poorly fermented humus. The clumped distribution of larvae is probably formed along the concentration gradient of CO2 induced by heterogeneity of fermented organic materials in soil. My laboratory experiments also revealed that larvae are chemically attracted to each other. Moreover, CO2 concentrations in soil were increased by the larval respiration, and small amounts of CO2 (much less than emitted during respiration by a single larva) were sufficient for larval attraction. These results suggest that not only response to fermented food resources, but also respiratory CO2 from conspecifics may lead to aggregation. Enhanced densities resulted in reduced weight gain under experimental conditions. However, exploiting a high-value resource at enhanced densities still led to greater body weight compared to individually exploiting a low-value resource. This demonstrates the adaptive value of the response to CO2 sources in this species. PMID:26536591

  5. Attraction to Carbon Dioxide from Feeding Resources and Conspecific Neighbours in Larvae of the Rhinoceros Beetle Trypoxylus dichotomus.

    PubMed

    Kojima, Wataru

    2015-01-01

    Saprophagous (feeding on decaying matter) insects often use carbon dioxide (CO2) as a cue for finding food. Humus-feeding larvae of the giant rhinoceros beetle Trypoxylus dichotomus exhibit a clumped distribution in natural microhabitats, but the mechanisms driving the distribution were unknown. Herein, I examined whether larvae use CO2 as a cue for fermented humus and aggregate in the vicinity of the food. I found that (i) larvae of T. dichotomus are strongly attracted to CO2, (ii) larvae orient toward highly fermented humus when given a choice between highly and poorly fermented humus, (iii) the highly fermented humus emits more CO2 than the poorly fermented humus, and (iv) larvae grow larger when fed highly fermented humus rather than poorly fermented humus. The clumped distribution of larvae is probably formed along the concentration gradient of CO2 induced by heterogeneity of fermented organic materials in soil. My laboratory experiments also revealed that larvae are chemically attracted to each other. Moreover, CO2 concentrations in soil were increased by the larval respiration, and small amounts of CO2 (much less than emitted during respiration by a single larva) were sufficient for larval attraction. These results suggest that not only response to fermented food resources, but also respiratory CO2 from conspecifics may lead to aggregation. Enhanced densities resulted in reduced weight gain under experimental conditions. However, exploiting a high-value resource at enhanced densities still led to greater body weight compared to individually exploiting a low-value resource. This demonstrates the adaptive value of the response to CO2 sources in this species.

  6. Considerations for reducing food system energy demand while scaling up urban agriculture

    NASA Astrophysics Data System (ADS)

    Mohareb, Eugene; Heller, Martin; Novak, Paige; Goldstein, Benjamin; Fonoll, Xavier; Raskin, Lutgarde

    2017-12-01

    There is an increasing global interest in scaling up urban agriculture (UA) in its various forms, from private gardens to sophisticated commercial operations. Much of this interest is in the spirit of environmental protection, with reduced waste and transportation energy highlighted as some of the proposed benefits of UA; however, explicit consideration of energy and resource requirements needs to be made in order to realize these anticipated environmental benefits. A literature review is undertaken here to provide new insight into the energy implications of scaling up UA in cities in high-income countries, considering UA classification, direct/indirect energy pressures, and interactions with other components of the food-energy-water nexus. This is followed by an exploration of ways in which these cities can plan for the exploitation of waste flows for resource-efficient UA. Given that it is estimated that the food system contributes nearly 15% of total US energy demand, optimization of resource use in food production, distribution, consumption, and waste systems may have a significant energy impact. There are limited data available that quantify resource demand implications directly associated with UA systems, highlighting that the literature is not yet sufficiently robust to make universal claims on benefits. This letter explores energy demand from conventional resource inputs, various production systems, water/energy trade-offs, alternative irrigation, packaging materials, and transportation/supply chains to shed light on UA-focused research needs. By analyzing data and cases from the existing literature, we propose that gains in energy efficiency could be realized through the co-location of UA operations with waste streams (e.g. heat, CO2, greywater, wastewater, compost), potentially increasing yields and offsetting life cycle energy demands relative to conventional approaches. This begs a number of energy-focused UA research questions that explore the opportunities for integrating the variety of UA structures and technologies, so that they are better able to exploit these urban waste flows and achieve whole-system reductions in energy demand. Any planning approach to implement these must, as always, assess how context will influence the viability and value added from the promotion of UA.

  7. DNA metabarcoding of nestling feces reveals provisioning of aquatic prey and resource partitioning among Neotropical migratory songbirds in a riparian habitat.

    PubMed

    Trevelline, Brian K; Nuttle, Tim; Hoenig, Brandon D; Brouwer, Nathan L; Porter, Brady A; Latta, Steven C

    2018-05-01

    Riparian habitats are characterized by substantial flows of emergent aquatic insects that cross the stream-forest interface and provide an important source of prey for insectivorous birds. The increased availability of prey arising from aquatic subsidies attracts high densities of Neotropical migratory songbirds that are thought to exploit emergent aquatic insects as a nestling food resource; however, the prey preferences and diets of birds in these communities are only broadly understood. In this study, we utilized DNA metabarcoding to investigate the extent to which three syntopic species of migratory songbirds-Acadian Flycatcher, Louisiana Waterthrush, and Wood Thrush-breeding in Appalachian riparian habitats (Pennsylvania, USA) exploit and partition aquatic prey subsidies as a nestling food resource. Despite substantial differences in adult foraging strategies, nearly every nestling in this study consumed aquatic taxa, suggesting that aquatic subsidies are an important prey resource for Neotropical migrants nesting in riparian habitats. While our results revealed significant interspecific dietary niche divergence, the diets of Acadian Flycatcher and Wood Thrush nestlings were strikingly similar and exhibited significantly more overlap than expected. These results suggest that the dietary niches of Neotropical migrants with divergent foraging strategies may converge due to the opportunistic provisioning of non-limiting prey resources in riparian habitats. In addition to providing the first application of DNA metabarcoding to investigate diet in a community of Neotropical migrants, this study emphasizes the importance of aquatic subsidies in supporting breeding songbirds and improves our understanding of how anthropogenic disturbances to riparian habitats may negatively impact long-term avian conservation.

  8. Stable isotopes reveal links between human food inputs and urban ant diets.

    PubMed

    Penick, Clint A; Savage, Amy M; Dunn, Robert R

    2015-05-07

    The amount of energy consumed within an average city block is an order of magnitude higher than that consumed in any other ecosystem over a similar area. This is driven by human food inputs, but the consequence of these resources for urban animal populations is poorly understood. We investigated the role of human foods in ant diets across an urbanization gradient in Manhattan using carbon and nitrogen stable isotopes. We found that some-but not all-ant species living in Manhattan's most urbanized habitats had δ(13)C signatures associated with processed human foods. In particular, pavement ants (Tetramorium sp. E) had increased levels of δ(13)C similar to δ(13)C levels in human fast foods. The magnitude of this effect was positively correlated with urbanization. By contrast, we detected no differences in δ(15)N, suggesting Tetramorium feeds at the same trophic level despite shifting to human foods. This pattern persisted across the broader ant community; species in traffic islands used human resources more than park species. Our results demonstrate that the degree urban ants exploit human resources changes across the city and among species, and this variation could play a key role in community structure and ecosystem processes where human and animal food webs intersect. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  9. Influence of climatic factors on the flight activity of the stingless bee Partamona orizabaensis and its competition behavior at food sources.

    PubMed

    Keppner, Eva M; Jarau, Stefan

    2016-10-01

    Stingless bees have evolved several ways to share contested resources to ensure the coexistence between different species. Partamona orizabaensis quickly exploits food sources by fast and direct recruitment that does not rely on scent marks deposited on substrates. In this study we show that the flight activity of P. orizabaensis is influenced by weather conditions, with higher activity during periods of colder temperatures, higher relative humidity and even during rainfall. We showed that the outcome of aggression experiments between the non-aggressive species P. orizabaensis and its aggressive competitor Trigona fuscipennis is influenced by the number of bees that arrive early after food source discovery. Therefore, the increased activity during less favorable weather conditions and the fast recruitment of nestmates following the discovery of a food source, as observed for P. orizabaensis, may be adaptations that evolved to coexist even with more aggressive and dominant species of stingless bees, with which P. orizabaensis has to compete for resources.

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

    PubMed

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

    2007-05-01

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

  11. Use of cattle farm resources by badgers (Meles meles) and risk of bovine tuberculosis (Mycobacterium bovis) transmission to cattle.

    PubMed

    Garnett, B T; Delahay, R J; Roper, T J

    2002-07-22

    Nocturnal observations, radio telemetry and time-lapse camera surveillance were used to investigate visits by badgers (Meles meles L.) to two cattle farms. During 59 half-nights (ca. 295 h) of observation and 17 nights (ca. 154 h) of camera surveillance, 139 separate visits to farm buildings, by at least 26 individually identifiable badgers from two social groups, were recorded. The badgers, which included three individuals infected with bovine tuberculosis (Mycobacterium bovis), used cowsheds, feedsheds, barns, haystacks, slurry pits, cattle troughs and farmyards to exploit a range of food resources, including cattle feed and silage. Cattle feed was contaminated with badger faeces and badgers also came into close contact with cattle. The minimum number of badgers visiting farm buildings per night was negatively correlated with local 24 h rainfall. We conclude that exploitation by badgers of resources provided by cattle farms constitutes a potentially important mechanism for tuberculosis transmission from badgers to cattle.

  12. Gastral drumming: a nest-based food-recruitment signal in a social wasp

    NASA Astrophysics Data System (ADS)

    Taylor, Benjamin J.; Jeanne, Robert L.

    2018-04-01

    Many social insect species produce signals that either recruit foragers to a specific food source or simply activate more nestmates to become foragers. Both are means of enhancing resource exploitation by increasing the number of individuals devoted to gathering profitable resources. Gastral drumming (GD) has been documented in several species of yellowjackets and hornets (Vespidae: Vespinae). It has been hypothesized that it is a hunger signal, but there is little empirical evidence to support this claim. An alternative hypothesis is that GD recruits workers to forage for food. Here, we report the results of a test between the hunger-signal and food-recruitment hypotheses in the German yellowjacket wasp, Vespula germanica. We show that the rate of performance of GD decreased when colonies were deprived of food and increased when supplemental food was provided. Playback of GD caused increased rates of (1) movement in the nest, (2) trophallaxis, and (3) worker departures from the nest. Together, these results support the conclusion that GD is not a hunger signal as previously asserted but instead is a nest-based food-recruitment signal, the first to be reported for a social wasp.

  13. Gastral drumming: a nest-based food-recruitment signal in a social wasp.

    PubMed

    Taylor, Benjamin J; Jeanne, Robert L

    2018-03-21

    Many social insect species produce signals that either recruit foragers to a specific food source or simply activate more nestmates to become foragers. Both are means of enhancing resource exploitation by increasing the number of individuals devoted to gathering profitable resources. Gastral drumming (GD) has been documented in several species of yellowjackets and hornets (Vespidae: Vespinae). It has been hypothesized that it is a hunger signal, but there is little empirical evidence to support this claim. An alternative hypothesis is that GD recruits workers to forage for food. Here, we report the results of a test between the hunger-signal and food-recruitment hypotheses in the German yellowjacket wasp, Vespula germanica. We show that the rate of performance of GD decreased when colonies were deprived of food and increased when supplemental food was provided. Playback of GD caused increased rates of (1) movement in the nest, (2) trophallaxis, and (3) worker departures from the nest. Together, these results support the conclusion that GD is not a hunger signal as previously asserted but instead is a nest-based food-recruitment signal, the first to be reported for a social wasp.

  14. The economic origins of ultrasociality.

    PubMed

    Gowdy, John; Krall, Lisi

    2016-01-01

    Ultrasociality refers to the social organization of a few species, including humans and some social insects, having a complex division of labor, city-states, and an almost exclusive dependence on agriculture for subsistence. We argue that the driving forces in the evolution of these ultrasocial societies were economic. With the agricultural transition, species could directly produce their own food and this was such a competitive advantage that those species now dominate the planet. Once underway, this transition was propelled by the selection of within-species groups that could best capture the advantages of (1) actively managing the inputs to food production, (2) a more complex division of labor, and (3) increasing returns to larger scale and larger group size. Together these factors reoriented productive life and radically altered the structure of these societies. Once agriculture began, populations expanded as these economic drivers opened up new opportunities for the exploitation of resources and the active management of inputs to food production. With intensified group-level competition, larger populations and intensive resource exploitation became competitive advantages, and the "social conquest of Earth" was underway. Ultrasocial species came to dominate the earth's ecosystems. Ultrasociality also brought a loss of autonomy for individuals within the group. We argue that exploring the common causes and consequences of ultrasociality in humans and the social insects that adopted agriculture can provide fruitful insights into the evolution of complex human society.

  15. Energy beyond food: foraging theory informs time spent in thermals by a large soaring bird.

    PubMed

    Shepard, Emily L C; Lambertucci, Sergio A; Vallmitjana, Diego; Wilson, Rory P

    2011-01-01

    Current understanding of how animals search for and exploit food resources is based on microeconomic models. Although widely used to examine feeding, such constructs should inform other energy-harvesting situations where theoretical assumptions are met. In fact, some animals extract non-food forms of energy from the environment, such as birds that soar in updraughts. This study examined whether the gains in potential energy (altitude) followed efficiency-maximising predictions in the world's heaviest soaring bird, the Andean condor (Vultur gryphus). Animal-attached technology was used to record condor flight paths in three-dimensions. Tracks showed that time spent in patchy thermals was broadly consistent with a strategy to maximise the rate of potential energy gain. However, the rate of climb just prior to leaving a thermal increased with thermal strength and exit altitude. This suggests higher rates of energetic gain may not be advantageous where the resulting gain in altitude would lead to a reduction in the ability to search the ground for food. Consequently, soaring behaviour appeared to be modulated by the need to reconcile differing potential energy and food energy distributions. We suggest that foraging constructs may provide insight into the exploitation of non-food energy forms, and that non-food energy distributions may be more important in informing patterns of movement and residency over a range of scales than previously considered.

  16. Longer and less overlapping food webs in anthropogenically disturbed marine ecosystems: confirmations from the past.

    PubMed

    Saporiti, Fabiana; Bearhop, Stuart; Silva, Laura; Vales, Damián G; Zenteno, Lisette; Crespo, Enrique A; Aguilar, Alex; Cardona, Luis

    2014-01-01

    The human exploitation of marine resources is characterised by the preferential removal of the largest species. Although this is expected to modify the structure of food webs, we have a relatively poor understanding of the potential consequences of such alteration. Here, we take advantage of a collection of ancient consumer tissues, using stable isotope analysis and SIBER to assess changes in the structure of coastal marine food webs in the South-western Atlantic through the second half of the Holocene as a result of the sequential exploitation of marine resources by hunter-gatherers, western sealers and modern fishermen. Samples were collected from shell middens and museums. Shells of both modern and archaeological intertidal herbivorous molluscs were used to reconstruct changes in the stable isotopic baseline, while modern and archaeological bones of the South American sea lion Otaria flavescens, South American fur seal Arctocephalus australis and Magellanic penguin Spheniscus magellanicus were used to analyse changes in the structure of the community of top predators. We found that ancient food webs were shorter, more redundant and more overlapping than current ones, both in northern-central Patagonia and southern Patagonia. These surprising results may be best explained by the huge impact of western sealing on pinnipeds during the fur trade period, rather than the impact of fishing on fish populations. As a consequence, the populations of pinnipeds at the end of the sealing period were likely well below the ecosystem's carrying capacity, which resulted in a release of intraspecific competition and a shift towards larger and higher trophic level prey. This in turn led to longer and less overlapping food webs.

  17. Habitat and food preferences of the endangered Palila (Loxioides bailleui) on Mauna Kea, Hawai'i

    USGS Publications Warehouse

    Hess, Steven C.; Banko, Paul C.; Miller, Linda J.; Laniawe, Leona P.

    2014-01-01

    Seeds and flowers of the leguminous māmane (Sophora chrysophylla) tree are the primary food resource of the federally endangered Palila (Loxioides bailleui; Fringillidae: Drepanidinae), which is now restricted to dry subalpine woodland on Mauna Kea Volcano on the island of Hawai'i because of centuries of habitat degradation by non-native ungulates. Palila are morphologically and behaviorally adapted to consume māmane seeds by grasping seed pods with their feet and opening pods with stout bills and demonstrate limited ability to exploit alternative food resources. This degree of single species dependency is rare among birds and illustrates unique adaptations that also occurred in other Hawaiian species that are now extinct. In mixed-woodland with co-dominant naio (Myoporum sandwicense), Palila spent 1.7-3.9 times longer in māmane than in naio during foraging observations where naio was 1.3-4.6 times as dense as māmane. Naio fruit was readily available, but it comprised proportionally <11% of food items taken by Palila. Although māmane flowers were more abundant than māmane pods throughout this study except at one lower-elevation mixed-woodland site, Palila spent more time foraging on pods than flowers in both māmane woodland and mixed-woodland, but consumed more flowers than pods in mixed-woodland. Insects, which have been reported as an important component of the diet of Palila, were apparently taken rarely in this study. Protecting and restoring māmane in woodlands adjacent to the current range of Palila will benefit their recovery, allowing them to exploit increased food availability in areas of their former range.

  18. Microbial oil - A plausible alternate resource for food and fuel application.

    PubMed

    Bharathiraja, B; Sridharan, Sridevi; Sowmya, V; Yuvaraj, D; Praveenkumar, R

    2017-06-01

    Microbes have recourse to low-priced substrates like agricultural wastes and industrial efflux. A pragmatic approach towards an emerging field- the exploitation of microbial oils for biodiesel production, pharmaceutical and cosmetic applications, food additives, biopolymer production will be of immense remunerative significance in the near future. Due to high free fatty acid, nutritive content and simpler solvent extraction processes of microbial oils with plant oil, microbial oils can back plant oils in food applications. The purpose of this review is to evaluate the opulence of lipid production in native and standard micro-organisms and also to emphasize the vast array of applications including food and fuel by obtaining maximum yield. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. The influence of simulated exploitation on Patella vulgata populations: protandric sex change is size-dependent.

    PubMed

    Borges, Carla D G; Hawkins, Stephen J; Crowe, Tasman P; Doncaster, C Patrick

    2016-01-01

    Grazing mollusks are used as a food resource worldwide, and limpets are harvested commercially for both local consumption and export in several countries. This study describes a field experiment to assess the effects of simulated human exploitation of limpets Patella vulgata on their population ecology in terms of protandry (age-related sex change from male to female), growth, recruitment, migration, and density regulation. Limpet populations at two locations in southwest England were artificially exploited by systematic removal of the largest individuals for 18 months in plots assigned to three treatments at each site: no (control), low, and high exploitation. The shell size at sex change (L 50: the size at which there is a 50:50 sex ratio) decreased in response to the exploitation treatments, as did the mean shell size of sexual stages. Size-dependent sex change was indicated by L 50 occurring at smaller sizes in treatments than controls, suggesting an earlier switch to females. Mean shell size of P. vulgata neuters changed little under different levels of exploitation, while males and females both decreased markedly in size with exploitation. No differences were detected in the relative abundances of sexual stages, indicating some compensation for the removal of the bigger individuals via recruitment and sex change as no migratory patterns were detected between treatments. At the end of the experiment, 0-15 mm recruits were more abundant at one of the locations but no differences were detected between treatments. We conclude that sex change in P. vulgata can be induced at smaller sizes by reductions in density of the largest individuals reducing interage class competition. Knowledge of sex-change adaptation in exploited limpet populations should underpin strategies to counteract population decline and improve rocky shore conservation and resource management.

  20. Dynamic habitat selection by two wading bird species with divergent foraging strategies in a seasonally fluctuating wetland

    USGS Publications Warehouse

    Beerens, James M.; Gawlik, Dale E.; Herring, Garth; Cook, Mark I.

    2011-01-01

    Seasonal and annual variation in food availability during the breeding season plays an influential role in the population dynamics of many avian species. In highly dynamic ecosystems like wetlands, finding and exploiting food resources requires a flexible behavioral response that may produce different population trends that vary with a species' foraging strategy. We quantified dynamic foraging-habitat selection by breeding and radiotagged White Ibises (Eudocimus albus) and Great Egrets (Ardea alba) in the Florida Everglades, where fluctuation in food resources is pronounced because of seasonal drying and flooding. The White Ibis is a tactile “searcher” species in population decline that specializes on highly concentrated prey, whereas the Great Egret, in a growing population, is a visual “exploiter” species that requires lower prey concentrations. In a year with high food availability, resource-selection functions for both species included variables that changed over multiannual time scales and were associated with increased prey production. In a year with low food availability, resource-selection functions included short-term variables that concentrated prey (e.g., water recession rates and reversals in drying pattern), which suggests an adaptive response to poor foraging conditions. In both years, the White Ibis was more restricted in its use of habitats than the Great Egret. Real-time species—habitat suitability models were developed to monitor and assess the daily availability and quality of spatially explicit habitat resources for both species. The models, evaluated through hindcasting using independent observations, demonstrated that habitat use of the more specialized White Ibis was more accurately predicted than that of the more generalist Great Egret.

  1. Spatial ecology of refuge selection by an herbivore under risk of predation

    USGS Publications Warehouse

    Wilson, Tammy L.; Rayburn, Andrew P.; Edwards, Thomas C.

    2012-01-01

    Prey species use structures such as burrows to minimize predation risk. The spatial arrangement of these resources can have important implications for individual and population fitness. For example, there is evidence that clustered resources can benefit individuals by reducing predation risk and increasing foraging opportunity concurrently, which leads to higher population density. However, the scale of clustering that is important in these processes has been ignored during theoretical and empirical development of resource models. Ecological understanding of refuge exploitation by prey can be improved by spatial analysis of refuge use and availability that incorporates the effect of scale. We measured the spatial distribution of pygmy rabbit (Brachylagus idahoensis) refugia (burrows) through censuses in four 6-ha sites. Point pattern analyses were used to evaluate burrow selection by comparing the spatial distribution of used and available burrows. The presence of food resources and additional overstory cover resources was further examined using logistic regression. Burrows were spatially clustered at scales up to approximately 25 m, and then regularly spaced at distances beyond ~40 m. Pygmy rabbit exploitation of burrows did not match availability. Burrows used by pygmy rabbits were likely to be located in areas with high overall burrow density (resource clusters) and high overstory cover, which together minimized predation risk. However, in some cases we observed an interaction between either overstory cover (safety) or understory cover (forage) and burrow density. The interactions show that pygmy rabbits will use burrows in areas with low relative burrow density (high relative predation risk) if understory food resources are high. This points to a potential trade-off whereby rabbits must sacrifice some safety afforded by additional nearby burrows to obtain ample forage resources. Observed patterns of clustered burrows and non-random burrow use improve understanding of the importance of spatial distribution of refugia for burrowing herbivores. The analyses used allowed for the estimation of the spatial scale where subtle trade-offs between predation avoidance and foraging opportunity are likely to occur in a natural system.

  2. Coexistence of three sympatric cormorants (Phalacrocorax spp.); partitioning of time as an ecological resource

    PubMed Central

    Mahendiran, Mylswamy

    2016-01-01

    Resource partitioning is well known along food and habitat for reducing competition among sympatric species, yet a study on temporal partitioning as a viable basis for reducing resource competition is not empirically investigated. Here, I attempt to identify the mechanism of temporal partitioning by intra- and interspecific diving analyses of three sympatric cormorant species at different freshwater wetlands around the Delhi region. Diving results indicated that cormorants opted for a shallow diving; consequently, they did not face any physiological stress. Moreover, diving durations were linked with seasons, foraging time and foraging habitats. Intraspecific comparison suggested that cormorants spent a longer time underwater in early hours of the day. Therefore, time spent for dive was higher in the forenoon than late afternoon, and the interspecific analysis also yielded a similar result. When Phalacrocorax niger and Phalacrocorax fuscicollis shared the same foraging habitat, they tended to differ in their foraging time (forenoon/afternoon). However, when P. niger and Phalacrocorax carbo shared the same foraging time, they tended to use different foraging habitats (lentic/lotic) leading to a mechanism of resource partitioning. Thus, sympatric cormorants effectively use time as a resource to exploit the food resources and successful coexistence. PMID:27293799

  3. Assessment of the trade-offs and synergies between low-carbon power sector transition and land and water resources of the United Kingdom using the "ForeseerTM" approach

    NASA Astrophysics Data System (ADS)

    Konadu, D. D.; Sobral Mourao, Z.

    2016-12-01

    Transitioning to a low-carbon power system has been identified as one of the main strategies for achieving GHG emissions reduction targets stipulated in the UK Climate Change Act (2008). However, projected mix of technologies aimed at achieving the targeted level of decarbonisation have implications for sustainable level natural resource exploitation at different spatial and temporal scales. Critical among these are the impact on land use (food production) and water resources, which are usually not adequately analysed and accounted for in developing these long-term energy system transition strategies and scenarios. Given the importance of the UK power sector to meeting economy-wide emissions targets, the overall environmental consequence of the prescribed scenarios could significantly affect meeting long-term legislated GHG emission reduction targets. It is therefore imperative that synergies and trade-offs between the power systems and these resources are comprehensively analysed. The current study employs an integrated energy and resource use accounting methodology, called ForeseerTM, to assess the land and water requirement for the deployment of the power sector technologies of the UK Committee on Climate Change (CCC) Carbon Budget scenarios. This is analysed under different scenarios of energy crop yield and electricity infrastructure location. The outputs are then compared with sustainable limits of resource exploitation to establish the environmental tractability of the scenarios. The results show that even if stringent environmental and land use restrictions are applied, all the projected bioenergy and ground-mounted solar PV can be deployed within the UK with no significant impacts on land use and food production. However, inland water resources would be significantly affected if high Carbon Capture and Storage deployment, and without new nuclear capacity. Overall, the output highlights that contrary to the notion of the inevitability of CCS deployment in delivering emissions reduction targets, a future without CCS poses the least overall environmental impacts.

  4. Interspecific aggression and habitat partitioning in garter snakes.

    PubMed

    Edgehouse, Michael; Latta, Leigh C; Brodie, Edmund D; Brodie, Edmund D

    2014-01-01

    Defense of a limited resource, such as space or food, has recently been discovered in snakes and has been widely documented in lizards. Garter snakes (Thamnophis spp.) are historically considered generalist predators such that food is not a limiting resource. However, in this study we show that the common garter snake (Thamnophis sirtalis) and the aquatic garter snake (Thamnophis atratus) show a strong preference for amphibians as their primary food source at the Santa Lucia Preserve (SLP), Monterey County, California. This food preference forces these snake species at SLP to exploit aquatic habitats. Our principle goal was to investigate the aggressive behavior of T. sirtalis and the potential that this aggression displaces T. atratus from its preferred habitat. We found that when individuals from either species are alone, a 100% preference for aquatic or near aquatic habitat is observed. In contrast, when these species are together, T. sirtalis occupy the aquatic habitat and T. atratus occupy an area far removed from water. Thamnophis sirtalis often physically force T. atratus from the aquatic habitat through repeated biting and other displays of aggression.

  5. Interspecific Aggression and Habitat Partitioning in Garter Snakes

    PubMed Central

    Edgehouse, Michael; Latta, Leigh C.; Brodie, Edmund D.; Brodie, Edmund D.

    2014-01-01

    Defense of a limited resource, such as space or food, has recently been discovered in snakes and has been widely documented in lizards. Garter snakes (Thamnophis spp.) are historically considered generalist predators such that food is not a limiting resource. However, in this study we show that the common garter snake (Thamnophis sirtalis) and the aquatic garter snake (Thamnophis atratus) show a strong preference for amphibians as their primary food source at the Santa Lucia Preserve (SLP), Monterey County, California. This food preference forces these snake species at SLP to exploit aquatic habitats. Our principle goal was to investigate the aggressive behavior of T. sirtalis and the potential that this aggression displaces T. atratus from its preferred habitat. We found that when individuals from either species are alone, a 100% preference for aquatic or near aquatic habitat is observed. In contrast, when these species are together, T. sirtalis occupy the aquatic habitat and T. atratus occupy an area far removed from water. Thamnophis sirtalis often physically force T. atratus from the aquatic habitat through repeated biting and other displays of aggression. PMID:24465962

  6. Size- and food-dependent growth drives patterns of competitive dominance along productivity gradients.

    PubMed

    Huss, Magnus; Gårdmark, Anna; Van Leeuwen, Anieke; de Roos, André M

    2012-04-01

    Patterns of coexistence among competing species exhibiting size- and food-dependent growth remain largely unexplored. Here we studied mechanisms behind coexistence and shifts in competitive dominance in a size-structured fish guild, representing sprat and herring stocks in the Baltic Sea, using a physiologically structured model of competing populations. The influence of degree of resource overlap and the possibility of undergoing ontogenetic diet shifts were studied as functions of zooplankton and zoobenthos productivity. By imposing different size-dependent mortalities, we could study the outcome of competition under contrasting environmental regimes representing poor and favorable growth conditions. We found that the identity of the dominant species shifted between low and high productivity. Adding a herring-exclusive benthos resource only provided a competitive advantage over sprat when size-dependent mortality was high enough to allow for rapid growth in the zooplankton niche. Hence, the importance of a bottom-up effect of varying productivity was dependent on a strong top-down effect. Although herring could depress shared resources to lower levels than could sprat and also could access an exclusive resource, the smaller size at maturation of sprat allowed it to coexist with herring and, in some cases, exclude it. Our model system, characterized by interactions among size cohorts, allowed for consumer coexistence even at full resource overlap at intermediate productivities when size-dependent mortality was low. Observed shifts in community patterns were crucially dependent on the explicit consideration of size- and food-dependent growth. Accordingly, we argue that accounting for food-dependent growth and size-dependent interactions is necessary to better predict changes in community structure and dynamics following changes in major ecosystem drivers such as resource productivity and mortality, which are fundamental for our ability to manage exploitation of living resources in, e.g., fisheries.

  7. Simple technologies and diverse food strategies of the Late Pleistocene and Early Holocene at Huaca Prieta, Coastal Peru

    PubMed Central

    Dillehay, Tom D.; Goodbred, Steve; Pino, Mario; Vásquez Sánchez, Víctor F.; Tham, Teresa Rosales; Adovasio, James; Collins, Michael B.; Netherly, Patricia J.; Hastorf, Christine A.; Chiou, Katherine L.; Piperno, Dolores; Rey, Isabel; Velchoff, Nancy

    2017-01-01

    Simple pebble tools, ephemeral cultural features, and the remains of maritime and terrestrial foods are present in undisturbed Late Pleistocene and Early Holocene deposits underneath a large human-made mound at Huaca Prieta and nearby sites on the Pacific coast of northern Peru. Radiocarbon ages indicate an intermittent human presence dated between ~15,000 and 8000 calendar years ago before the mound was built. The absence of fishhooks, harpoons, and bifacial stone tools suggests that technologies of gathering, trapping, clubbing, and exchange were used primarily to procure food resources along the shoreline and in estuarine wetlands and distant mountains. The stone artifacts are minimally worked unifacial stone tools characteristic of several areas of South America. Remains of avocado, bean, and possibly cultivated squash and chile pepper are also present, suggesting human transport and consumption. Our new findings emphasize an early coastal lifeway of diverse food procurement strategies that suggest detailed observation of resource availability in multiple environments and a knowledgeable economic organization, although technologies were simple and campsites were seemingly ephemeral and discontinuous. These findings raise questions about the pace of early human movement along some areas of the Pacific coast and the level of knowledge and technology required to exploit maritime and inland resources. PMID:28560337

  8. Simple technologies and diverse food strategies of the Late Pleistocene and Early Holocene at Huaca Prieta, Coastal Peru.

    PubMed

    Dillehay, Tom D; Goodbred, Steve; Pino, Mario; Vásquez Sánchez, Víctor F; Tham, Teresa Rosales; Adovasio, James; Collins, Michael B; Netherly, Patricia J; Hastorf, Christine A; Chiou, Katherine L; Piperno, Dolores; Rey, Isabel; Velchoff, Nancy

    2017-05-01

    Simple pebble tools, ephemeral cultural features, and the remains of maritime and terrestrial foods are present in undisturbed Late Pleistocene and Early Holocene deposits underneath a large human-made mound at Huaca Prieta and nearby sites on the Pacific coast of northern Peru. Radiocarbon ages indicate an intermittent human presence dated between ~15,000 and 8000 calendar years ago before the mound was built. The absence of fishhooks, harpoons, and bifacial stone tools suggests that technologies of gathering, trapping, clubbing, and exchange were used primarily to procure food resources along the shoreline and in estuarine wetlands and distant mountains. The stone artifacts are minimally worked unifacial stone tools characteristic of several areas of South America. Remains of avocado, bean, and possibly cultivated squash and chile pepper are also present, suggesting human transport and consumption. Our new findings emphasize an early coastal lifeway of diverse food procurement strategies that suggest detailed observation of resource availability in multiple environments and a knowledgeable economic organization, although technologies were simple and campsites were seemingly ephemeral and discontinuous. These findings raise questions about the pace of early human movement along some areas of the Pacific coast and the level of knowledge and technology required to exploit maritime and inland resources.

  9. ESA's Food Security Thematic Exploitation Platform "Supporting Sustainable Food Production from Space"

    NASA Astrophysics Data System (ADS)

    Gilliams, S. J.

    2017-12-01

    In line with the paradigm shift in Earth Observation of "Bringing the users to the data", ESA provides collaborative, virtual work environments giving access to EO data and tools, processors, and ICT resources through coherent interfaces. These coherent interfaces are categorized thematically, tailored to the related user communities and named Thematic Exploitation Platforms (TEP). The Food Security Thematic Exploitation Platform (FS-TEP) is the youngest out of seven TEPs and is developed in an agile mode in close coordination with its users. It will provide a "one stop platform" for the extraction of information from EO data for services in the food security sector mainly in Europe & Africa, allowing both access to EO data and processing of these data sets. Thereby it will foster smart, data-intensive agricultural and aquacultural applications in the scientific, private and public domain. The FS-TEP builds on a large and heterogeneous user community, spanning from application developers in agriculture to aquaculture, from small-scale farmers to agricultural industry, from public science to the finance and insurance sectors, from local and national administration to international agencies. To meet the requirements of these groups, the FS-TEP will provide different frontend interfaces. Service pilots will demonstrate the platform's ability to support agriculture and aquaculture with tailored EO based information services.The project team developing the FS-TEP and implementing pilot services during a 30 months period (started in April 2017) is led by Vista GmbH, Germany, supported by CGI Italy, VITO, Belgium, and Hatfield Consultants, Canada. It is funded by ESA under contract number 4000120074/17/I-EF.

  10. China Report, Agriculture, No. 260.

    DTIC Science & Technology

    1983-06-09

    Deep- Sea , Coastal Fishing (XINHUA, 2U May 83) 32 World Food Program To Aid PRC Dairy Industry (XINHUA, 28 May 83) 33 More on WFP Aid...PRC TO EXPAND DEEP- SEA , COASTAL FISHING OW241245 Beijing XINHUA in English 1159 GMT 24 May 83 [Text] Beijing, May 24 (XINHUA)—China will expand...fishing in the open seas while protecting, cultivating and rationally exploiting coastal resources, said Meng Xiande, director of the Aquatic

  11. Wild inside: Urban wild boar select natural, not anthropogenic food resources.

    PubMed

    Stillfried, Milena; Gras, Pierre; Busch, Matthias; Börner, Konstantin; Kramer-Schadt, Stephanie; Ortmann, Sylvia

    2017-01-01

    Most wildlife species are urban avoiders, but some became urban utilizers and dwellers successfully living in cities. Often, they are assumed to be attracted into urban areas by easily accessible and highly energetic anthropogenic food sources. We macroscopically analysed stomachs of 247 wild boar (Sus scrofa, hereafter WB) from urban areas of Berlin and from the surrounding rural areas. From the stomach contents we determined as predictors of food quality modulus of fineness (MOF,), percentage of acid insoluble ash (AIA) and macronutrients such as amount of energy and percentage of protein, fat, fibre and starch. We run linear mixed models to test: (1) differences in the proportion of landscape variables, (2) differences of nutrients consumed in urban vs. rural WB and (3) the impact of landscape variables on gathered nutrients. We found only few cases of anthropogenic food in the qualitative macroscopic analysis. We categorized the WB into five stomach content categories but found no significant difference in the frequency of those categories between urban and rural WB. The amount of energy was higher in stomachs of urban WB than in rural WB. The analysis of landscape variables revealed that the energy of urban WB increased with increasing percentage of sealing, while an increased human density resulted in poor food quality for urban and rural WB. Although the percentage of protein decreased in areas with a high percentage of coniferous forests, the food quality increased. High percentage of grassland decreased the percentage of consumed fat and starch and increased the percentage of fibre, while a high percentage of agricultural areas increased the percentage of consumed starch. Anthropogenic food such as garbage might serve as fallback food when access to natural resources is limited. We infer that urban WB forage abundant, natural resources in urban areas. Urban WB might use anthropogenic resources (e.g. garbage) if those are easier to exploit and more abundant than natural resources. This study shows that access to natural resources still is mandatory and drives the amount of protein, starch, fat or fibre in wild boar stomachs in urban as well as rural environments.

  12. Wild inside: Urban wild boar select natural, not anthropogenic food resources

    PubMed Central

    Stillfried, Milena; Gras, Pierre; Busch, Matthias; Börner, Konstantin; Kramer-Schadt, Stephanie; Ortmann, Sylvia

    2017-01-01

    Most wildlife species are urban avoiders, but some became urban utilizers and dwellers successfully living in cities. Often, they are assumed to be attracted into urban areas by easily accessible and highly energetic anthropogenic food sources. We macroscopically analysed stomachs of 247 wild boar (Sus scrofa, hereafter WB) from urban areas of Berlin and from the surrounding rural areas. From the stomach contents we determined as predictors of food quality modulus of fineness (MOF,), percentage of acid insoluble ash (AIA) and macronutrients such as amount of energy and percentage of protein, fat, fibre and starch. We run linear mixed models to test: (1) differences in the proportion of landscape variables, (2) differences of nutrients consumed in urban vs. rural WB and (3) the impact of landscape variables on gathered nutrients. We found only few cases of anthropogenic food in the qualitative macroscopic analysis. We categorized the WB into five stomach content categories but found no significant difference in the frequency of those categories between urban and rural WB. The amount of energy was higher in stomachs of urban WB than in rural WB. The analysis of landscape variables revealed that the energy of urban WB increased with increasing percentage of sealing, while an increased human density resulted in poor food quality for urban and rural WB. Although the percentage of protein decreased in areas with a high percentage of coniferous forests, the food quality increased. High percentage of grassland decreased the percentage of consumed fat and starch and increased the percentage of fibre, while a high percentage of agricultural areas increased the percentage of consumed starch. Anthropogenic food such as garbage might serve as fallback food when access to natural resources is limited. We infer that urban WB forage abundant, natural resources in urban areas. Urban WB might use anthropogenic resources (e.g. garbage) if those are easier to exploit and more abundant than natural resources. This study shows that access to natural resources still is mandatory and drives the amount of protein, starch, fat or fibre in wild boar stomachs in urban as well as rural environments. PMID:28403244

  13. Chaco Chachalaca (Ortalis canicollis, Wagler, 1830) feeding ecology in a gallery forest in the South Pantanal (Brazil).

    PubMed

    Ragusa-Netto, J

    2015-01-01

    Cracids are generalist frugivores, which often exploit plant food resources such as flowers and leaves, mainly when fruit production declines. The Chaco chachalaca (Ortalis canicollis) is the most abundant cracid in the Pantanal (Brazil), and particularly common in the gallery forests. However, the factors related to their occurrence in this habitat type are unclear. In this study I describe the feeding habits and feeding niche breadth fluctuations of the Chaco chachalaca in relation to food resources abundance and diversity at the Miranda river gallery forest (Southern Pantanal). I also analyzed the relationships between Chaco chachalacas feeding activity and food resources abundance. This parameter (flowers and fruits) exhibited significant seasonal differences of abundance in which flowers were plentiful at the end of the dry, while fruits were abundant during the early wet season. However, food resources diversity to Chaco chachalacas exhibited no seasonal difference. Their feeding activity paralleled the availability of food resources, so that when some items were massively available an enhanced number of Chaco chachalacas foraged in the gallery forest, particularly during the prolonged dry season when they extensively used flowers and Genipa americana fruits. In fact, the Chaco chachalaca feeding niche breadth value presented low values in this period, while high values were common in the rest of the year. The flexible diet of this cracid, potentially favors their year round presence in the gallery forest, mainly during the prolonged dry season when the propensity for famine might be high. Since the Chaco chachalaca is among the largest and most abundant canopy frugivores in the gallery forest, it may contribute to forest regeneration, an underscored role due to the impact of annual floods and meandering dynamics on tree loss.

  14. Expanding the biotechnology potential of lactobacilli through comparative genomics of 213 strains and associated genera.

    PubMed

    Sun, Zhihong; Harris, Hugh M B; McCann, Angela; Guo, Chenyi; Argimón, Silvia; Zhang, Wenyi; Yang, Xianwei; Jeffery, Ian B; Cooney, Jakki C; Kagawa, Todd F; Liu, Wenjun; Song, Yuqin; Salvetti, Elisa; Wrobel, Agnieszka; Rasinkangas, Pia; Parkhill, Julian; Rea, Mary C; O'Sullivan, Orla; Ritari, Jarmo; Douillard, François P; Paul Ross, R; Yang, Ruifu; Briner, Alexandra E; Felis, Giovanna E; de Vos, Willem M; Barrangou, Rodolphe; Klaenhammer, Todd R; Caufield, Page W; Cui, Yujun; Zhang, Heping; O'Toole, Paul W

    2015-09-29

    Lactobacilli are a diverse group of species that occupy diverse nutrient-rich niches associated with humans, animals, plants and food. They are used widely in biotechnology and food preservation, and are being explored as therapeutics. Exploiting lactobacilli has been complicated by metabolic diversity, unclear species identity and uncertain relationships between them and other commercially important lactic acid bacteria. The capacity for biotransformations catalysed by lactobacilli is an untapped biotechnology resource. Here we report the genome sequences of 213 Lactobacillus strains and associated genera, and their encoded genetic catalogue for modifying carbohydrates and proteins. In addition, we describe broad and diverse presence of novel CRISPR-Cas immune systems in lactobacilli that may be exploited for genome editing. We rationalize the phylogenomic distribution of host interaction factors and bacteriocins that affect their natural and industrial environments, and mechanisms to withstand stress during technological processes. We present a robust phylogenomic framework of existing species and for classifying new species.

  15. Expanding the biotechnology potential of lactobacilli through comparative genomics of 213 strains and associated genera

    PubMed Central

    Sun, Zhihong; Harris, Hugh M. B.; McCann, Angela; Guo, Chenyi; Argimón, Silvia; Zhang, Wenyi; Yang, Xianwei; Jeffery, Ian B; Cooney, Jakki C.; Kagawa, Todd F.; Liu, Wenjun; Song, Yuqin; Salvetti, Elisa; Wrobel, Agnieszka; Rasinkangas, Pia; Parkhill, Julian; Rea, Mary C.; O'Sullivan, Orla; Ritari, Jarmo; Douillard, François P.; Paul Ross, R.; Yang, Ruifu; Briner, Alexandra E.; Felis, Giovanna E.; de Vos, Willem M.; Barrangou, Rodolphe; Klaenhammer, Todd R.; Caufield, Page W.; Cui, Yujun; Zhang, Heping; O'Toole, Paul W.

    2015-01-01

    Lactobacilli are a diverse group of species that occupy diverse nutrient-rich niches associated with humans, animals, plants and food. They are used widely in biotechnology and food preservation, and are being explored as therapeutics. Exploiting lactobacilli has been complicated by metabolic diversity, unclear species identity and uncertain relationships between them and other commercially important lactic acid bacteria. The capacity for biotransformations catalysed by lactobacilli is an untapped biotechnology resource. Here we report the genome sequences of 213 Lactobacillus strains and associated genera, and their encoded genetic catalogue for modifying carbohydrates and proteins. In addition, we describe broad and diverse presence of novel CRISPR-Cas immune systems in lactobacilli that may be exploited for genome editing. We rationalize the phylogenomic distribution of host interaction factors and bacteriocins that affect their natural and industrial environments, and mechanisms to withstand stress during technological processes. We present a robust phylogenomic framework of existing species and for classifying new species. PMID:26415554

  16. Ballistic food transport in toucans.

    PubMed

    Baussart, Sabine; Korsoun, Leonid; Libourel, Paul-Antoine; Bels, Vincent

    2009-08-01

    The basic mechanism of food transport in tetrapods is lingual-based. Neognathous birds use this mechanism for exploiting a large diversity of food resources, whereas paleognathous birds use cranioinertial mechanism with or without tongue involvement. Food transport in two neognathous species of toucans (Ramphastos toco and R. vitellinus) is defined as ballistic transport mechanism. Only one transport cycle is used for moving the food from the tip of the beak to the pharynx. The food is projected between jaws with similar initial velocity in both species. At the time of release, the angle between trajectory of food position and horizontal is higher in R. vitellinus with a shorter beak than in R. toco. The tongue never makes contact with the food nor is it used to expand the buccal cavity. Tongue movement is associated with throat expansion, permitting the food to reach the entrance of the esophagus at the end of the ballistic trajectory. Selection of large food items in the diet may explain the evolutionary trend of using ballistic transport in the feeding behavior of toucans, which plays a key role in ecology of tropical forest. 2009 Wiley-Liss, Inc.

  17. Medical geology in the framework of the sustainable development goals.

    PubMed

    Bundschuh, Jochen; Maity, Jyoti Prakash; Mushtaq, Shahbaz; Vithanage, Meththika; Seneweera, Saman; Schneider, Jerusa; Bhattacharya, Prosun; Khan, Nasreen Islam; Hamawand, Ihsan; Guilherme, Luiz R G; Reardon-Smith, Kathryn; Parvez, Faruque; Morales-Simfors, Nury; Ghaze, Sara; Pudmenzky, Christa; Kouadio, Louis; Chen, Chien-Yen

    2017-03-01

    Exposure to geogenic contaminants (GCs) such as metal(loid)s, radioactive metals and isotopes as well as transuraniums occurring naturally in geogenic sources (rocks, minerals) can negatively impact on environmental and human health. The GCs are released into the environment by natural biogeochemical processes within the near-surface environments and/or by anthropogenic activities such as mining and hydrocarbon exploitation as well as exploitation of geothermal resources. They can contaminate soil, water, air and biota and subsequently enter the food chain with often serious health impacts which are mostly underestimated and poorly recognized. Global population explosion and economic growth and the associated increase in demand for water, energy, food, and mineral resources result in accelerated release of GCs globally. The emerging science of "medical geology" assesses the complex relationships between geo-environmental factors and their impacts on humans and environments and is related to the majority of the 17 Sustainable Development Goals in the 2030 Agenda of the United Nations for Sustainable Development. In this paper, we identify multiple lines of evidence for the role of GCs in the incidence of diseases with as yet unknown etiology (causation). Integrated medical geology promises a more holistic understanding of the occurrence, mobility, bioavailability, bio-accessibility, exposure and transfer mechanisms of GCs to the food-chain and humans, and the related ecotoxicological impacts and health effects. Scientific evidence based on this approach will support adaptive solutions for prevention, preparedness and response regarding human and environmental health impacts originating from exposure to GCs. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Tandem carrying, a new foraging strategy in ants: description, function, and adaptive significance relative to other described foraging strategies

    NASA Astrophysics Data System (ADS)

    Guénard, Benoit; Silverman, Jules

    2011-08-01

    An important aspect of social insect biology lies in the expression of collective foraging strategies developed to exploit food. In ants, four main types of foraging strategies are typically recognized based on the intensity of recruitment and the importance of chemical communication. Here, we describe a new type of foraging strategy, "tandem carrying", which is also one of the most simple recruitment strategies, observed in the Ponerinae species Pachycondyla chinensis. Within this strategy, workers are directly carried individually and then released on the food resource by a successful scout. We demonstrate that this recruitment is context dependent and based on the type of food discovered and can be quickly adjusted as food quality changes. We did not detect trail marking by tandem-carrying workers. We conclude by discussing the importance of tandem carrying in an evolutionary context relative to other modes of recruitment in foraging and nest emigration.

  19. Fluctuations in daily energy intake do not cause physiological stress in a Neotropical primate living in a seasonal forest.

    PubMed

    Martínez-Mota, Rodolfo; Righini, Nicoletta; Palme, Rupert

    2016-12-01

    Animals may face periods of nutritional stress due to short-term food shortage and/or low energy consumption associated with seasonal fluctuations in resource availability. We tested the hypothesis that periods of restricted macronutrient and energy intake result in energy deficits and physiological stress in wild black howler monkeys (Alouatta pigra) inhabiting seasonal tropical semi-deciduous forests. We conducted full-day follows of focal animals recording feeding rates, time spent feeding, and total amount of food ingested. We carried out nutritional analysis of foods collected from feeding trees and calculated the daily nutrient and energy intake of each focal individual. Fecal glucocorticoid metabolites (fGCM) of focal animals were used as an indicator of physiological stress. We found that fluctuations in daily energy intake across seasons did not have significant effects on fGCM of individuals. However, protein intake was negatively associated with fGCM, highlighting the interplay among macronutrients, metabolism, and the endocrine system. Fecal glucocorticoid metabolites were also positively related to fruit availability, but this relationship was most likely due to social stress associated with intergroup encounters and resource defense that occurred when preferred trees were fruiting. Behavioral strategies such as dietary shifts and nutrient mixing, and metabolic adaptations such as low energy expenditure allowed individuals to fulfill their minimum energy requirements even during periods of decreased resource availability and intake. The present study suggests that seasonal variations in food, macronutrient, and energy acquisition may have limited physiological costs for animals that exploit different types of plant resources such as howler monkeys.

  20. Floral resource utilization by solitary bees (Hymenoptera: Apoidea) and exploitation of their stored foods by natural enemies.

    PubMed

    Wcislo, W T; Cane, J H

    1996-01-01

    Bees are phytophagous insects that exhibit recurrent ecological specializations related to factors generally different from those discussed for other phytophagous insects. Pollen specialists have undergone extensive radiations, and specialization is not always a derived state. Floral host associations are conserved in some bee lineages. In others, various species specialize on different host plants that are phenotypically similar in presenting predictably abundant floral resources. The nesting of solitary bees in localized areas influences the intensity of interactions with enemies and competitors. Abiotic factors do not always explain the intraspecific variation in the spatial distribution of solitary bees. Foods stored by bees attract many natural enemies, which may shape diverse facets of nesting and foraging behavior. Parasitism has evolved repeatedly in some, but not all, bee lineages. Available evidence suggests that cleptoparasitic lineages are most speciose in temperate zones. Female parasites frequently have a suite of characters that can be described as a masculinized feminine form. The evolution of resource specialization (including parasitism) in bees presents excellent opportunities to investigate phenotypic mechanisms responsible for evolutionary change.

  1. Toward a synthetic economic systems modeling tool for sustainable exploitation of ecosystems.

    PubMed

    Richardson, Colin; Courvisanos, Jerry; Crawford, John W

    2011-02-01

    Environmental resources that underpin the basic human needs of water, energy, and food are predicted to become in such short supply by 2050 that global security and the well-being of millions will be under threat. These natural commodities have been allowed to reach crisis levels of supply because of a failure of economic systems to sustain them. This is largely because there have been no means of integrating their exploitation into any economic model that effectively addresses ecological systemic failures in a way that provides an integrated ecological-economic tool that can monitor and evaluate market and policy targets. We review the reasons for this and recent attempts to address the problem while identifying outstanding issues. The key elements of a policy-oriented economic model that integrates ecosystem processes are described and form the basis of a proposed new synthesis approach. The approach is illustrated by an indicative case study that develops a simple model for rainfed and irrigated food production in the Murray-Darling basin of southeastern Australia. © 2011 New York Academy of Sciences.

  2. Contrafreeloading in grizzly bears: implications for captive foraging enrichment.

    PubMed

    McGowan, Ragen T S; Robbins, Charles T; Alldredge, J Richard; Newberry, Ruth C

    2010-01-01

    Although traditional feeding regimens for captive animals were focused on meeting physiological needs to assure good health, more recently emphasis has also been placed on non-nutritive aspects of feeding. The provision of foraging materials to diversify feeding behavior is a common practice in zoos but selective consumption of foraging enrichment items over more balanced "chow" diets could lead to nutrient imbalance. One alternative is to provide balanced diets in a contrafreeloading paradigm. Contrafreeloading occurs when animals choose resources that require effort to exploit when identical resources are freely available. To investigate contrafreeloading and its potential as a theoretical foundation for foraging enrichment, we conducted two experiments with captive grizzly bears (Ursus arctos horribilis). In Experiment 1, bears were presented with five foraging choices simultaneously: apples, apples in ice, salmon, salmon in ice, and plain ice under two levels of food restriction. Two measures of contrafreeloading were considered: weight of earned food consumed and time spent working for earned food. More free than earned food was eaten, with only two bears consuming food extracted from ice, but all bears spent more time manipulating ice containing salmon or apples than plain ice regardless of level of food restriction. In Experiment 2, food-restricted bears were presented with three foraging choices simultaneously: apples, apples inside a box, and an empty box. Although they ate more free than earned food, five bears consumed food from boxes and all spent more time manipulating boxes containing apples than empty boxes. Our findings support the provision of contrafreeloading opportunities as a foraging enrichment strategy for captive wildlife. (c) 2009 Wiley-Liss, Inc.

  3. The development of plant food processing in the Levant: insights from use-wear analysis of Early Epipalaeolithic ground stone tools

    PubMed Central

    Dubreuil, Laure; Nadel, Dani

    2015-01-01

    In recent years, the study of percussive, pounding and grinding tools has provided new insights into human evolution, more particularly regarding the development of technology enabling the processing and exploitation of plant resources. Some of these studies focus on early evidence for flour production, an activity frequently perceived as an important step in the evolution of plant exploitation. The present paper investigates plant food preparation in mobile hunter-gatherer societies from the Southern Levant. The analysis consists of a use-wear study of 18 tools recovered from Ohalo II, a 23 000-year-old site in Israel showing an exceptional level of preservation. Our sample includes a slab previously interpreted as a lower implement used for producing flour, based on the presence of cereal starch residues. The use-wear data we have obtained provide crucial information about the function of this and other percussive tools at Ohalo II, as well as on investment in tool manufacture, discard strategies and evidence for plant processing in the Late Pleistocene. The use-wear analysis indicates that the production of flour was a sporadic activity at Ohalo II, predating by thousands of years the onset of routine processing of plant foods. PMID:26483535

  4. The development of plant food processing in the Levant: insights from use-wear analysis of Early Epipalaeolithic ground stone tools.

    PubMed

    Dubreuil, Laure; Nadel, Dani

    2015-11-19

    In recent years, the study of percussive, pounding and grinding tools has provided new insights into human evolution, more particularly regarding the development of technology enabling the processing and exploitation of plant resources. Some of these studies focus on early evidence for flour production, an activity frequently perceived as an important step in the evolution of plant exploitation. The present paper investigates plant food preparation in mobile hunter-gatherer societies from the Southern Levant. The analysis consists of a use-wear study of 18 tools recovered from Ohalo II, a 23 000-year-old site in Israel showing an exceptional level of preservation. Our sample includes a slab previously interpreted as a lower implement used for producing flour, based on the presence of cereal starch residues. The use-wear data we have obtained provide crucial information about the function of this and other percussive tools at Ohalo II, as well as on investment in tool manufacture, discard strategies and evidence for plant processing in the Late Pleistocene. The use-wear analysis indicates that the production of flour was a sporadic activity at Ohalo II, predating by thousands of years the onset of routine processing of plant foods. © 2015 The Author(s).

  5. What counts for ants? How return behaviour and food search of Cataglyphis ants are modified by variations in food quantity and experience.

    PubMed

    Bolek, Siegfried; Wittlinger, Matthias; Wolf, Harald

    2012-09-15

    When finding more food than one is able to carry home, should one come back to the site to exploit it further? This question is crucial for central place foragers that provide for a home place with brood or nest mates. The benefit of returning has to be weighed against the chance of finding food elsewhere and the resources available. Desert ants Cataglyphis fortis are well-studied examples when it comes to navigating back and forth between their nest and a foraging area, due to their primary reliance on path integration in the open and featureless desert habitat. The ants use path integration not only for a safe return from their foraging trips but also for future returns to plentiful feeding sites. The direction from the nest that has previously yielded food items is preferred for future foraging trips, a phenomenon termed sector fidelity. What prompts the ants to return to a particular site, and how faithfully they search for that place, has not been well studied. We examine the evaluation of food sources in channel experiments by varying both the number of food items in a feeder and the number of visits to the feeder before testing search distances of foragers returning to the feeding site. Ants exhibited more focused searches for plentiful food sources than for sources with only few food items upon their first return visit. After several successful visits, the ants always searched thoroughly for the food source, independent of the amount of food offered. Thus, desert ants consider both food abundance and reliability of food encounter, with corroborative learning of reliability gradually overriding the initial preference for plentiful feeders. The density of food items appears to be used by the ants as a proxy for food abundance. On the level of our analysis, the searches performed in the experimental channels are indistinguishable from those performed in the open desert terrain. The present results not only demonstrate how otherwise well-studied desert ants assess yield and experience with reliability of food sources, but also establish a model system for future study of how itemised food sources are exploited.

  6. Ideas towards sustainable water security

    NASA Astrophysics Data System (ADS)

    Dalin, Carole

    2016-04-01

    With growing global demands and a changing climate, ensuring water security - the access to sufficient, quality water resources for health and livelihoods and an acceptable level of water related risk - is increasingly challenging. While a billion people still lack access to water, over-exploitation of this resource increases in many developed and developing parts of the world. While some solutions to water stress have been known for a long time, financial, cultural and political barriers often prevent their implementations. This talk will highlight three crucial areas that need to be addressed to progress towards sustainable water security. The first point is on scale, the second on the agricultural sector and irrigation, and the third on food trade and policy.

  7. Sustainability of coastal resource use in San Quintin, Mexico

    USGS Publications Warehouse

    Aguirre-Munoz, A.; Buddemeier, R.W.; Camacho-lbar, V.; Carriquiry, J.D.; Ibarra-Obando, S.E.; Massey, Barbara W.; Smith, S.V.; Wulff, F.

    2001-01-01

    San Quintin, Mexico, provides a useful site for integrated analyses of material fluxes and socioeconomic constraints in a geographically isolated system. Natural resource utilization on the land is dominated by groundwater exploitation for cultivation of horticulture crops (primarily tomatoes). Irrigation exceeds water recharge minus export by a factor of 6. Resource utilization in the bay is dominated by oyster culture; food for the oysters is provided by tidal exchange of bay and ocean water. Consideration of oyster respiration and system respiration suggests that the present level of aquaculture is about 40% of the sustainable level. A "physical unsustainability index" (PhUI) was developed to measure the proportional departure of utilization of the most limiting resource for sustainability: 6 on land; 0.4 in the bay. Based on PhUI and measures of economic development, we conclude that aquaculture is more viable than agriculture.

  8. Sustainability of coastal resource use in San Quintin, Mexico.

    PubMed

    Aguirre-Muñoz, A; Buddemeier, R W; Camacho-Ibar, V; Carriquiry, J D; Ibarra-Obando, S E; Massey, B W; Smith, S V; Wulff, F

    2001-05-01

    San Quintin, Mexico, provides a useful site for integrated analyses of material fluxes and socioeconomic constraints in a geographically isolated system. Natural resource utilization on the land is dominated by groundwater exploitation for cultivation of horticulture crops (primarily tomatoes). Irrigation exceeds water recharge minus export by a factor of 6. Resource utilization in the bay is dominated by oyster culture; food for the oysters is provided by tidal exchange of bay and ocean water. Consideration of oyster respiration and system respiration suggests that the present level of aquaculture is about 40% of the sustainable level. A "physical unsustainability index" (PhUI) was developed to measure the proportional departure of utilization of the most limiting resource for sustainability: 6 on land; 0.4 in the bay. Based on PhUI and measures of economic development, we conclude that aquaculture is more viable than agriculture.

  9. Is Diet Flexibility an Adaptive Life Trait for Relictual and Peri-Urban Populations of the Endangered Primate Macaca sylvanus?

    PubMed Central

    Maibeche, Yasmina; Moali, Aissa; Yahi, Nassima; Menard, Nelly

    2015-01-01

    Habitat loss, fragmentation and urban expansion may drive some species to marginal habitats while others succeed in exploiting urban areas. Species that show dietary flexibility are more able to take advantage of human activities to supplement their diet with anthropogenically abundant and accessible resources. The Barbary macaque (Macaca sylvanus) is an endangered species due to the loss of its habitat, and human pressure. The population of Gouraya National Park (Algeria) lives in a relictual habitat that constitutes about 0.6% of the species range. In addition, this population is a unique case where urban expansion favours contact zones between Barbary macaque habitats and a big city (Bejaia). We quantified the dietary composition of Gouraya macaques over an annual cycle with the objective to understand how diet flexibility of this species may help it adapt to a relictual habitat or cope with urban expansion. We recorded the phenology of plant species every month. This study shows that Gouraya macaques, compared to those living in other forest types of the distribution area, are under lower seasonal constraints. They consume a greater amount of fruit and seeds that are available throughout much of the year, and a lesser amount of costly to find and extract subterranean foods. Therefore the Gouraya relictual habitat appears as a favourable environment compared to other major habitats of that species. This study also shows that colonizing peri-urban zones increases the availability and species richness of diet resources for Barbary macaques as they consume more human foods and exotic plants than in farther sites. Adult males eat more human foods than adult females and immatures do. The exploitation of high-energy anthropogenic food could favour macaque population growth and expansion towards the city center associated with human/macaque conflicts. We recommend applying management actions to restore macaques back to their natural habitat. PMID:25714476

  10. Mean trophic level of coastal fisheries landings in the Persian Gulf (Hormuzgan Province), 2002-2011

    NASA Astrophysics Data System (ADS)

    Razzaghi, Marzieh; Mashjoor, Sakineh; Kamrani, Ehsan

    2017-05-01

    Fishing activities can alter the structure of marine food webs by the selective removal of some species. The changes in the marine food webs of the Hormuzgan waters of the Persian Gulf, Iran were assessed, based on estimates of the mean trophic index (MTI) and Fishing in Balance index (FiB), and on landing profile of the exploited marine community (49 species) during the period, 2002-2011. The total landings ( Y t) ( R=0.88, P<0.001) increased gradually while the Y t of carnivores has slightly declined, and the Y t of herbivores, detritivores and omnivores has increased. Consequently, the MTI significantly decreased ( R =-0.69, P<0.05) at a rate of 0.11 during this decade. The MTI showed a decreasing trend, which indicates exploitation of marine resources. The FiB index also showed a downward trend and negative values from 2002 to 2009, which may be associated with unbalanced structure in the fisheries, but an upward trend from 2009 to 2011. The time variation of the landing profile showed two periods with significant diff erences in their species composition ( R=0.88; P =0.005), and based on analysis of similarity, species have been identified as discriminator species, namely Thunnus albacores and Benthosema pterotum. Results indicate that changes in MTI reflected changes in the Hormuzgan landing structure. The examination of the MTI, FBI, and landing profile (LP) temporal pattern suggests that the status of fishery resources in Hormuzgan inshore waters is overexploited, and provides evidence of the probability that a fishing down process is occurring in this area, and that this trend may continue in the long-term. Therefore, environmental fisheries management and conservation programs should be prioritized for these valuable resources.

  11. Molar Macrowear Reveals Neanderthal Eco-Geographic Dietary Variation

    PubMed Central

    Fiorenza, Luca; Benazzi, Stefano; Tausch, Jeremy; Kullmer, Ottmar; Bromage, Timothy G.; Schrenk, Friedemann

    2011-01-01

    Neanderthal diets are reported to be based mainly on the consumption of large and medium sized herbivores, while the exploitation of other food types including plants has also been demonstrated. Though some studies conclude that early Homo sapiens were active hunters, the analyses of faunal assemblages, stone tool technologies and stable isotopic studies indicate that they exploited broader dietary resources than Neanderthals. Whereas previous studies assume taxon-specific dietary specializations, we suggest here that the diet of both Neanderthals and early Homo sapiens is determined by ecological conditions. We analyzed molar wear patterns using occlusal fingerprint analysis derived from optical 3D topometry. Molar macrowear accumulates during the lifespan of an individual and thus reflects diet over long periods. Neanderthal and early Homo sapiens maxillary molar macrowear indicates strong eco-geographic dietary variation independent of taxonomic affinities. Based on comparisons with modern hunter-gatherer populations with known diets, Neanderthals as well as early Homo sapiens show high dietary variability in Mediterranean evergreen habitats but a more restricted diet in upper latitude steppe/coniferous forest environments, suggesting a significant consumption of high protein meat resources. PMID:21445243

  12. Genetic diversity within honeybee colonies increases signal production by waggle-dancing foragers

    PubMed Central

    Mattila, Heather R; Burke, Kelly M; Seeley, Thomas D

    2008-01-01

    Recent work has demonstrated considerable benefits of intracolonial genetic diversity for the productivity of honeybee colonies: single-patriline colonies have depressed foraging rates, smaller food stores and slower weight gain relative to multiple-patriline colonies. We explored whether differences in the use of foraging-related communication behaviour (waggle dances and shaking signals) underlie differences in foraging effort of genetically diverse and genetically uniform colonies. We created three pairs of colonies; each pair had one colony headed by a multiply mated queen (inseminated by 15 drones) and one colony headed by a singly mated queen. For each pair, we monitored the production of foraging-related signals over the course of 3 days. Foragers in genetically diverse colonies had substantially more information available to them about food resources than foragers in uniform colonies. On average, in genetically diverse colonies compared with genetically uniform colonies, 36% more waggle dances were identified daily, dancers performed 62% more waggle runs per dance, foragers reported food discoveries that were farther from the nest and 91% more shaking signals were exchanged among workers each morning prior to foraging. Extreme polyandry by honeybee queens enhances the production of worker–worker communication signals that facilitate the swift discovery and exploitation of food resources. PMID:18198143

  13. Genetic Diversity of Cowpea (Vigna unguiculata (L.) Walp.) Accession in Kenya Gene Bank Based on Simple Sequence Repeat Markers.

    PubMed

    Wamalwa, Emily N; Muoma, John; Wekesa, Clabe

    2016-01-01

    Increased agricultural production is an urgent issue. Projected global population is 9 million people by mid of this century. Estimation projects death of 1 million people for lack of food quality (micronutrient deficit) and quantity (protein deficit). Majority of these people will be living in developing countries. Other global challenges include shrinking cultivable lands, salinity, and flooding due to climate changes, new emerging pathogens, and pests. These affect crop production. Furthermore, they are major threats to crop genetic resources and food security. Genetic diversity in cultivated crops indicates gene pool richness. It is the greatest resource for plant breeders to select lines that enhance food security. This study was conducted by Masinde Muliro University to evaluate genetic diversity in 19 cowpea accessions from Kenya national gene bank. Accessions clustered into two major groups. High divergence was observed between accessions from Ethiopia and Australia and those from Western Kenya. Upper Volta accessions were closely related to those from Western Kenya. Low variation was observed between accessions from Eastern and Rift Valley than those from Western and Coastal regions of Kenya. Diversity obtained in this study can further be exploited for the improvement of cowpea in Kenya as a measure of food security.

  14. Ancient lipids document continuity in the use of early hunter-gatherer pottery through 9,000 years of Japanese prehistory.

    PubMed

    Lucquin, Alexandre; Gibbs, Kevin; Uchiyama, Junzo; Saul, Hayley; Ajimoto, Mayumi; Eley, Yvette; Radini, Anita; Heron, Carl P; Shoda, Shinya; Nishida, Yastami; Lundy, Jasmine; Jordan, Peter; Isaksson, Sven; Craig, Oliver E

    2016-04-12

    The earliest pots in the world are from East Asia and date to the Late Pleistocene. However, ceramic vessels were only produced in large numbers during the warmer and more stable climatic conditions of the Holocene. It has long been assumed that the expansion of pottery was linked with increased sedentism and exploitation of new resources that became available with the ameliorated climate, but this hypothesis has never been tested. Through chemical analysis of their contents, we herein investigate the use of pottery across an exceptionally long 9,000-y sequence from the Jōmon site of Torihama in western Japan, intermittently occupied from the Late Pleistocene to the mid-Holocene. Molecular and isotopic analyses of lipids from 143 vessels provides clear evidence that pottery across this sequence was predominantly used for cooking marine and freshwater resources, with evidence for diversification in the range of aquatic products processed during the Holocene. Conversely, there is little indication that ruminant animals or plants were processed in pottery, although it is evident from the faunal and macrobotanical remains that these foods were heavily exploited. Supported by other residue analysis data from Japan, our results show that the link between pottery and fishing was established in the Late Paleolithic and lasted well into the Holocene, despite environmental and socio-economic change. Cooking aquatic products in pottery represents an enduring social aspect of East Asian hunter-gatherers, a tradition based on a dependable technology for exploiting a sustainable resource in an uncertain and changing world.

  15. Firewood, food and human niche construction: the potential role of Mesolithic hunter-gatherers in actively structuring Scotland's woodlands

    NASA Astrophysics Data System (ADS)

    Bishop, Rosie R.; Church, Mike J.; Rowley-Conwy, Peter A.

    2015-01-01

    Over the past few decades the potential role of Mesolithic hunter-gatherers in actively constructing their own niches, through the management of wild plants, has frequently been discussed. It is probable that Mesolithic hunter-gatherers systematically exploited specific woodland resources for food and fuel and influenced the 'natural' abundance or distribution of particular species within Mesolithic environments. Though there has been considerable discussion of the pollen evidence for potential small-scale human-woodland manipulation in Mesolithic Scotland, the archaeobotanical evidence for anthropogenic firewood and food selection has not been discussed in this context. This paper assesses the evidence for the active role of Mesolithic hunter-gatherer communities in systematically exploiting and managing woodlands for food and fuel in Scotland. While taphonomic factors may have impacted on the frequency of specific species in archaeobotanical assemblages, it is suggested that hunter-gatherers in Mesolithic Scotland were systematically using woodland plants, and in particular hazel and oak, for food and fuel. It is argued that the pollen evidence for woodland management is equivocal, but hints at the role of hunter-gatherers in shaping the structure of their environments, through the maintenance or creation of woodland clearings for settlement or as part of vegetation management strategies. It is proposed that Mesolithic hunter-gatherers may have actively contributed to niche construction and that the systematic use of hazel and oak as a fuel may reflect the deliberate pruning of hazel trees to increase nut-yields and the inadvertent - or perhaps deliberate - coppicing of hazel and oak during greenwood collection.

  16. Treeline proximity alters an alpine plant-herbivore interaction.

    PubMed

    Illerbrun, Kurt; Roland, Jens

    2011-05-01

    Rising treeline threatens the size and contiguity of alpine meadows worldwide. As trees encroach into previously open habitat, the movement and population dynamics of above-treeline alpine species may be disrupted. This process is well documented in studies of the Rocky Mountain apollo butterfly (Parnassius smintheus). However, subtler consequences of treeline rise remain poorly understood. In this study, we examine whether treeline proximity affects feeding behaviour of P. smintheus larvae, due to altered habitat affecting the distribution and availability of their host plant, lance-leaved stonecrop (Sedum lanceolatum). Understanding differential larval exploitation of food resources in relation to the treeline is an important step in predicting the consequences of continued treeline rise. Parnassius smintheus larvae feed more intensively on S. lanceolatum away from the treeline despite the relative paucity of hosts in these areas, and despite higher fitness penalties associated with the plant's herbivory-induced chemical defenses. Sedum lanceolatum growing near the treeline is less attractive, and therefore represents a less significant resource for P. smintheus larvae than its abundance might imply. If treeline rise continues, we suggest that this pattern of altered resource exploitation may represent a mechanism by which larvae are adversely affected even while adult movement among and within meadows appears sufficient for maintaining population health, and total host availability seems ample.

  17. Sensory exploitation as an evolutionary origin to nuptial food gifts in insects.

    PubMed Central

    Sakaluk, S K

    2000-01-01

    Nuptial food gifts given by males to females at mating are widespread in insects, but their evolutionary origin remains obscure. Such gifts may arise as a form of sensory trap that exploits the normal gustatory responses of females, favouring the selective retention of sperm of gift-giving males. I tested this hypothesis by offering foreign food gifts, synthesized by males of one cricket species, to females of three non-gift-giving species. Females provisioned with novel food gifts were 'fooled' into accepting more sperm than they otherwise would in the absence of a gift. These results support the hypothesis that nuptial food gifts and post-copulatory female mating preferences coevolve through a unique form of sensory exploitation. PMID:10722214

  18. Stable isotope evidence for increasing dietary breadth in the European mid-Upper Paleolithic

    PubMed Central

    Richards, Michael P.; Pettitt, Paul B.; Stiner, Mary C.; Trinkaus, Erik

    2001-01-01

    New carbon and nitrogen stable isotope values for human remains dating to the mid-Upper Paleolithic in Europe indicate significant amounts of aquatic (fish, mollusks, and/or birds) foods in some of their diets. Most of this evidence points to exploitation of inland freshwater aquatic resources in particular. By contrast, European Neandertal collagen carbon and nitrogen stable isotope values do not indicate significant use of inland aquatic foods but instead show that they obtained the majority of their protein from terrestrial herbivores. In agreement with recent zooarcheological analyses, the isotope results indicate shifts toward a more broad-spectrum subsistence economy in inland Europe by the mid-Upper Paleolithic period, probably associated with significant population increases. PMID:11371652

  19. Stable isotope evidence for increasing dietary breadth in the European mid-Upper Paleolithic.

    PubMed

    Richards, M P; Pettitt, P B; Stiner, M C; Trinkaus, E

    2001-05-22

    New carbon and nitrogen stable isotope values for human remains dating to the mid-Upper Paleolithic in Europe indicate significant amounts of aquatic (fish, mollusks, and/or birds) foods in some of their diets. Most of this evidence points to exploitation of inland freshwater aquatic resources in particular. By contrast, European Neandertal collagen carbon and nitrogen stable isotope values do not indicate significant use of inland aquatic foods but instead show that they obtained the majority of their protein from terrestrial herbivores. In agreement with recent zooarcheological analyses, the isotope results indicate shifts toward a more broad-spectrum subsistence economy in inland Europe by the mid-Upper Paleolithic period, probably associated with significant population increases.

  20. Assessing the land resource-food price nexus of the Sustainable Development Goals.

    PubMed

    Obersteiner, Michael; Walsh, Brian; Frank, Stefan; Havlík, Petr; Cantele, Matthew; Liu, Junguo; Palazzo, Amanda; Herrero, Mario; Lu, Yonglong; Mosnier, Aline; Valin, Hugo; Riahi, Keywan; Kraxner, Florian; Fritz, Steffen; van Vuuren, Detlef

    2016-09-01

    The 17 Sustainable Development Goals (SDGs) call for a comprehensive new approach to development rooted in planetary boundaries, equity, and inclusivity. The wide scope of the SDGs will necessitate unprecedented integration of siloed policy portfolios to work at international, regional, and national levels toward multiple goals and mitigate the conflicts that arise from competing resource demands. In this analysis, we adopt a comprehensive modeling approach to understand how coherent policy combinations can manage trade-offs among environmental conservation initiatives and food prices. Our scenario results indicate that SDG strategies constructed around Sustainable Consumption and Production policies can minimize problem-shifting, which has long placed global development and conservation agendas at odds. We conclude that Sustainable Consumption and Production policies (goal 12) are most effective at minimizing trade-offs and argue for their centrality to the formulation of coherent SDG strategies. We also find that alternative socioeconomic futures-mainly, population and economic growth pathways-generate smaller impacts on the eventual achievement of land resource-related SDGs than do resource-use and management policies. We expect that this and future systems analyses will allow policy-makers to negotiate trade-offs and exploit synergies as they assemble sustainable development strategies equal in scope to the ambition of the SDGs.

  1. Moringa oleifera Seeds and Oil: Characteristics and Uses for Human Health.

    PubMed

    Leone, Alessandro; Spada, Alberto; Battezzati, Alberto; Schiraldi, Alberto; Aristil, Junior; Bertoli, Simona

    2016-12-20

    Moringa oleifera seeds are a promising resource for food and non-food applications, due to their content of monounsaturated fatty acids with a high monounsaturated/saturated fatty acids (MUFA/SFA) ratio, sterols and tocopherols, as well as proteins rich in sulfated amino acids. The rapid growth of Moringa trees in subtropical and tropical areas, even under conditions of prolonged drought, makes this plant a reliable resource to enhance the nutritional status of local populations and, if rationalized cultivation practices are exploited, their economy, given that a biodiesel fuel could be produced from a source not in competition with human food crops. Despite the relatively diffuse use of Moringa seeds and their oil in traditional medicine, no pharmacological activity study has been conducted on humans. Some encouraging evidence, however, justifies new efforts to obtain clear and definitive information on the benefits to human health arising from seed consumption. A critical review of literature data concerning the composition of Moringa oil has set in motion a plan for future investigations. Such investigations, using the seeds and oil, will focus on cultivation conditions to improve plant production, and will study the health effects on human consumers of Moringa seeds and their oil.

  2. Moringa oleifera Seeds and Oil: Characteristics and Uses for Human Health

    PubMed Central

    Leone, Alessandro; Spada, Alberto; Battezzati, Alberto; Schiraldi, Alberto; Aristil, Junior; Bertoli, Simona

    2016-01-01

    Moringa oleifera seeds are a promising resource for food and non-food applications, due to their content of monounsaturated fatty acids with a high monounsaturated/saturated fatty acids (MUFA/SFA) ratio, sterols and tocopherols, as well as proteins rich in sulfated amino acids. The rapid growth of Moringa trees in subtropical and tropical areas, even under conditions of prolonged drought, makes this plant a reliable resource to enhance the nutritional status of local populations and, if rationalized cultivation practices are exploited, their economy, given that a biodiesel fuel could be produced from a source not in competition with human food crops. Despite the relatively diffuse use of Moringa seeds and their oil in traditional medicine, no pharmacological activity study has been conducted on humans. Some encouraging evidence, however, justifies new efforts to obtain clear and definitive information on the benefits to human health arising from seed consumption. A critical review of literature data concerning the composition of Moringa oil has set in motion a plan for future investigations. Such investigations, using the seeds and oil, will focus on cultivation conditions to improve plant production, and will study the health effects on human consumers of Moringa seeds and their oil. PMID:27999405

  3. Reproducing butterflies do not increase intake of antioxidants when they could benefit from them

    PubMed Central

    Bischofberger, Ines; Lorenz, Isabel; Scheelen, Lucie; Fischer, Klaus

    2016-01-01

    The significance of dietary antioxidants may be limited by the ability of animals to exploit them. However, past studies have focused on the effects of dietary antioxidants after ‘antioxidant forced-feeding’, and have overlooked spontaneous antioxidant intake. Here, we found that reproducing female Bicyclus anynana butterflies had higher antioxidant defences and enhanced fecundity when forced to consume antioxidants (polyphenols). Interestingly, these positive effects were not constant across the oviposition period. When given the choice between food resources with and without antioxidants, reproducing butterflies did not target antioxidants when they could have benefited the most from them. Moreover, they did not consume more antioxidants than non-reproducing butterflies. These results emphasize that, despite potential positive effects of dietary antioxidants, the ability of animals to exploit them is likely to restrict their ecological significance. PMID:26911341

  4. Reproducing butterflies do not increase intake of antioxidants when they could benefit from them.

    PubMed

    Beaulieu, Michaël; Bischofberger, Ines; Lorenz, Isabel; Scheelen, Lucie; Fischer, Klaus

    2016-02-01

    The significance of dietary antioxidants may be limited by the ability of animals to exploit them. However, past studies have focused on the effects of dietary antioxidants after 'antioxidant forced-feeding', and have overlooked spontaneous antioxidant intake. Here, we found that reproducing female Bicyclus anynana butterflies had higher antioxidant defences and enhanced fecundity when forced to consume antioxidants (polyphenols). Interestingly, these positive effects were not constant across the oviposition period. When given the choice between food resources with and without antioxidants, reproducing butterflies did not target antioxidants when they could have benefited the most from them. Moreover, they did not consume more antioxidants than non-reproducing butterflies. These results emphasize that, despite potential positive effects of dietary antioxidants, the ability of animals to exploit them is likely to restrict their ecological significance. © 2016 The Author(s).

  5. Closing the cycle on food and energy resource flows in order to create a more sustainable rural economy in Nicaragua

    NASA Astrophysics Data System (ADS)

    Casillas, C. E.

    2009-12-01

    The ecologically sustainable development of economies is often discussed at the urban scale and framed in terms of the environmental threats that accompany rapid growth. The dynamics of rural economies are less complex and provide valuable insights into how resource flows may be better utilized, as well what are the critical roles and relationships of government and society. This paper will present a case study of economic and ecologically appropriate innovations that can be made to the production and consumption behavior within a community on the Atlantic Coast of Nicaragua. Orinoco is a small Garifuna community situated on the Pearl Lagoon basin. It has a population of over 1000 people and its economy is primarily based on the exploitation of declining shrimp and fish resources. This paper will quantify the monetary and material resource flows comprising the current economy, and present technically viable alternatives that would utilize the abundant natural resources in a more ecologically sustainable manner, while decreasing the dependence on imported food and fuels. Specifically, the paper will describe how recently implemented projects of energy conservation can be coupled with improved agricultural and fishing practices in order to meet local and external market demands for fish and vegetable oil. Secondary products can be utilized to eliminate the dependence on imported liquid and gas fossil fuels for cooking and electricity generation.

  6. Territorial behavior in Taiwanese kukrisnakes (Oligodon formosanus)

    PubMed Central

    Huang, Wen-San; Greene, Harry W.; Chang, Tien-Jye; Shine, Richard

    2011-01-01

    The independent evolutionary origin of a complex trait, within a lineage otherwise lacking it, provides a powerful opportunity to test hypotheses on selective forces. Territorial defense of an area containing resources (such as food or shelter) is widespread in lizards but not snakes. Our studies on an insular population of Taiwanese kukrisnakes (Oligodon formosanus) show that females of this species actively defend sea turtle nests by repelling conspecifics for long periods (weeks) until the turtle eggs hatch or are consumed. A clutch of turtle eggs comprises a large, long-lasting food resource, unlike the prey types exploited by other types of snakes. Snakes of this species have formidable weaponry (massively enlarged teeth that are used for slitting eggshells), and when threatened, these snakes wave their tails toward the aggressor (an apparent case of head-tail mimicry). Bites to the tail during intraspecific combat bouts thus can have high fitness costs for males (because the hemipenes are housed in the tail). In combination, unusual features of the species (ability to inflict severe damage to male conspecifics) and the local environment (a persistent prey resource, large relative to the snakes consuming it) render resource defense both feasible and advantageous for female kukrisnakes. The (apparently unique) evolution of territorial behavior in this snake species thus provides strong support for the hypothesis that resource defensibility is critical to the evolution of territoriality. PMID:21502515

  7. Why do forest products become less available?A pan-tropical comparison of drivers of forest-resource degradation

    NASA Astrophysics Data System (ADS)

    Hermans-Neumann, Kathleen; Gerstner, Katharina; Geijzendorffer, Ilse R.; Herold, Martin; Seppelt, Ralf; Wunder, Sven

    2016-12-01

    Forest products provide an important source of income and wellbeing for rural smallholder communities across the tropics. Although tropical forest products frequently become over-exploited, only few studies explicitly address the dynamics of degradation in response to socio-economic drivers. Our study addresses this gap by analyzing the factors driving changes in tropical forest products in the perception of rural smallholder communities. Using the poverty and environment network global dataset, we studied recently perceived trends of forest product availability considering firewood, charcoal, timber, food, medicine, forage and other forest products. We looked at a pan-tropical sample of 233 villages with forest access. Our results show that 90% of the villages experienced declining availability of forest resources over the last five years according to the informants. Timber and fuelwood together with forest foods were featured as the most strongly affected, though with marked differences across continents. In contrast, availability of at least one main forest product was perceived to increase in only 39% of the villages. Furthermore, the growing local use of forest resources is seen as the main culprit for the decline. In villages with both growing forest resource use and immigration—vividly illustrating demographic pressures—the strongest forest resources degradation was observed. Conversely, villages with little or no population growth and a decreased use of forest resources were most likely to see significant forest-resource increases. Further, villages are less likely to perceive resource declines when local communities own a significant share of forest area. Our results thus suggest that perceived resource declines have only exceptionally triggered adaptations in local resource-use and management patterns that would effectively deal with scarcity. Hence, at the margin this supports neo-Malthusian over neo-Boserupian explanations of local resource-use dynamics.

  8. Managing uncertainty: information and insurance under the risk of starvation.

    PubMed Central

    Dall, Sasha R X; Johnstone, Rufus A

    2002-01-01

    In an uncertain world, animals face both unexpected opportunities and danger. Such outcomes can select for two potential strategies: collecting information to reduce uncertainty, or insuring against it. We investigate the relative value of information and insurance (energy reserves) under starvation risk by offering model foragers a choice between constant and varying food sources over finite foraging bouts. We show that sampling the variable option (choosing it when it is not expected to be good) should decline both with lower reserves and late in foraging bouts; in order to be able to reap the reduction in uncertainty associated with exploiting a variable resource effectively, foragers must be able to afford and compensate for an initial increase in the risk of an energetic shortfall associated with choosing the option when it is bad. Consequently, expected exploitation of the varying option increases as it becomes less variable, and when the overall risk of energetic shortfall is reduced. In addition, little activity on the variable alternative is expected until reserves are built up early in a foraging bout. This indicates that gathering information is a luxury while insurance is a necessity, at least when foraging on stochastic and variable food under the risk of starvation. PMID:12495509

  9. Is honey a fallback food for wild chimpanzees or just a sweet treat?

    PubMed

    McLennan, Matthew R

    2015-12-01

    Honey is a highly nutritious resource for any primate able to exploit it. Wild chimpanzees exploit nests of honey-making bees (Apini and Meliponini) for honey and brood, typically using tools to overcome the bees' defences. The universality of honey-gathering among modern human foragers in tropical climates and chimpanzees suggests energy-rich honey, acquired with tools, was likely a regular food for ancestral hominins. However, few studies have assessed its role in seasonal foraging strategies of chimpanzees. This study asks whether honey serves as a high-quality fallback food for chimpanzees at Bulindi, Uganda. Honey consumption was investigated via fecal analysis over 22 months during two studies (Study 1: 2007-2008; Study 2: 2012-2014). Additionally, flower and fruit phenology was measured during Study 1; peak flowering intensity was expected to facilitate increased honey and/or brood production by bees. Chimpanzees consumed honey (and/or brood) at low frequencies year-round, but bees/beeswax appeared in feces at higher frequencies with decreasing fruit availability (Study 1). Honey consumption was unrelated to flowering and chimpanzees did not consume honey more frequently during the "honey season" when local people harvest beehives. Moreover, consumption was inversely related to fruit intake (both study periods). Although honey fits the functional definition of a filler fallback food at Bulindi, the chimpanzees unlikely depend on honey to replace nutrients provided by fruit. Overall, honey best qualifies as an energy-dense "treat" during low fruiting months. The data lend support to the hypothesis that tools can facilitate chimpanzees' access to high-quality fallbacks including insect foods when fruit availability is low. © 2015 Wiley Periodicals, Inc.

  10. The Contribution of Buckwheat Genetic Resources to Health and Dietary Diversity

    PubMed Central

    Sytar, Oksana; Brestic, Marian; Zivcak, Marek; Tran, Lam-Son Phan

    2016-01-01

    Despite several reports on the beneficial effects of buckwheat in prevention of human diseases, little attention has been devoted to the variability of biochemical and physiological traits in different buckwheat genetic resources. This review describes the biochemical evaluation of buckwheat genetic resources and the identification of elite genotypes for plant breeding and exploitation. The various types of bioactive compounds present in different varieties provide basic background information needed for the efficient production of buckwheat foods with added value. In this review, we will provide an integrated view of the biochemistry of bioactive compounds of buckwheat plants of different origin, especially of fagopyrin, proteins and amino acids, as well as of other phenolic compounds including rutin and chlorogenic acid. In addition to the genetic background, the effect of different growth conditions is discussed. The health effects of fagopyrin, phenolic acids, specific proteins and rutin are also presented. PMID:27252586

  11. Biological impacts of local vs. regional land use on a small tributary of the Seine River (France): insights from a food web approach based on stable isotopes.

    PubMed

    Hette-Tronquart, Nicolas; Oberdorff, Thierry; Tales, Evelyne; Zahm, Amandine; Belliard, Jérôme

    2017-03-23

    As part of the landscape, streams are influenced by land use. Here, we contributed to the understanding of the biological impacts of land use on streams, investigating how landscape effects vary with spatial scales (local vs. regional). We adopted a food web approach integrating both biological structure and functioning, to focus on the overall effect of land use on stream biocœnosis. We selected 17 sites of a small tributary of the Seine River (France) for their contrasted land use, and conducted a natural experiment by sampling three organic matter sources, three macroinvertebrate taxa, and most of the fish community. Using stable isotope analysis, we calculated three food web metrics evaluating two major dimensions of the trophic diversity displayed by the fish community: (i) the diversity of exploited resources and (ii) the trophic level richness. The idea was to examine whether (1) land-use effects varied according to spatial scales, (2) land use affected food webs through an effect on community structure and (3) land use affected food webs through an effect on available resources. Beside an increase in trophic diversity from upstream to downstream, our empirical data showed that food webs were influenced by land use in the riparian corridors (local scale). The effect was complex, and depended on site's position along the upstream-downstream gradient. By contrast, land use in the catchment (regional scale) did not influence stream biocœnosis. At the local scale, community structure was weakly influenced by land use, and thus played a minor role in explaining food web modifications. Our results suggested that the amount of available resources at the base of the food web was partly responsible for food web modifications. In addition, changes in biological functioning (i.e. feeding interactions) can also explain another part of the land-use effect. These results highlight the role played by the riparian corridors as a buffer zone, and advocate that riparian corridor should be at the centre of water management attention.

  12. Untapped Resources: Biotechnological Potential of Peptides and Secondary Metabolites in Archaea

    PubMed Central

    Charlesworth, James C.; Burns, Brendan P.

    2015-01-01

    Archaea are an understudied domain of life often found in “extreme” environments in terms of temperature, salinity, and a range of other factors. Archaeal proteins, such as a wide range of enzymes, have adapted to function under these extreme conditions, providing biotechnology with interesting activities to exploit. In addition to producing structural and enzymatic proteins, archaea also produce a range of small peptide molecules (such as archaeocins) and other novel secondary metabolites such as those putatively involved in cell communication (acyl homoserine lactones), which can be exploited for biotechnological purposes. Due to the wide array of metabolites produced there is a great deal of biotechnological potential from antimicrobials such as diketopiperazines and archaeocins, as well as roles in the cosmetics and food industry. In this review we will discuss the diversity of small molecules, both peptide and nonpeptide, produced by archaea and their potential biotechnological applications. PMID:26504428

  13. Botanochemicals and chemurgy in the petroleum drought ahead

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

    Bagby, M.O.; Buchanan, R.A.; Duke, J.A.

    1979-01-01

    Green plants, collectively, are still a major under-exploited resource. However, new crops and agricultural systems are being developed for the production of fuels and materials in addition to foods and fibers. Whole-plant oils and botanochemicals are being evaluated as annually renewable replacements for petroleum crude and petrochemicals, respectively. Plant derived fuel alcohols are becoming a viable supplement to gasoline and fuel oils. Polyisoprenes, terpenes, oils, waxes, alcohols, phenols, furfural, methane, and producer gas from plant sources can potentially displace petroleum derived feedstocks for the synthetic chemical industry. Moreover, new botanochemical processing methods offer prospects for reducing US dependence on importsmore » for many specialty plant-products traditionally produced by labor-intensive methods. Extraction of essential oils, pharmaceutical intermediates, tannins, and vegetable dyes may be integrated with botanochemical processing to allow exploitation of the varied US climate for domestic production of nearly every botanical now imported.« less

  14. Exploitation of pocket gophers and their food caches by grizzly bears

    USGS Publications Warehouse

    Mattson, D.J.

    2004-01-01

    I investigated the exploitation of pocket gophers (Thomomys talpoides) by grizzly bears (Ursus arctos horribilis) in the Yellowstone region of the United States with the use of data collected during a study of radiomarked bears in 1977-1992. My analysis focused on the importance of pocket gophers as a source of energy and nutrients, effects of weather and site features, and importance of pocket gophers to grizzly bears in the western contiguous United States prior to historical extirpations. Pocket gophers and their food caches were infrequent in grizzly bear feces, although foraging for pocket gophers accounted for about 20-25% of all grizzly bear feeding activity during April and May. Compared with roots individually excavated by bears, pocket gopher food caches were less digestible but more easily dug out. Exploitation of gopher food caches by grizzly bears was highly sensitive to site and weather conditions and peaked during and shortly after snowmelt. This peak coincided with maximum success by bears in finding pocket gopher food caches. Exploitation was most frequent and extensive on gently sloping nonforested sites with abundant spring beauty (Claytonia lanceolata) and yampah (Perdieridia gairdneri). Pocket gophers are rare in forests, and spring beauty and yampah roots are known to be important foods of both grizzly bears and burrowing rodents. Although grizzly bears commonly exploit pocket gophers only in the Yellowstone region, this behavior was probably widespread in mountainous areas of the western contiguous United States prior to extirpations of grizzly bears within the last 150 years.

  15. Resource waves: phenological diversity enhances foraging opportunities for mobile consumers

    USGS Publications Warehouse

    Armstrong, Jonathan B.; Takimoto, Gaku; Schindler, Daniel E.; Hayes, Matthew M.; Kauffman, Matthew J.

    2016-01-01

    Time can be a limiting constraint for consumers, particularly when resource phenology mediates foraging opportunity. Though a large body of research has explored how resource phenology influences trophic interactions, this work has focused on the topics of trophic mismatch or predator swamping, which typically occur over short periods, at small spatial extents or coarse resolutions. In contrast many consumers integrate across landscape heterogeneity in resource phenology, moving to track ephemeral food sources that propagate across space as resource waves. Here we provide a conceptual framework to advance the study of phenological diversity and resource waves. We define resource waves, review evidence of their importance in recent case studies, and demonstrate their broader ecological significance with a simulation model. We found that consumers ranging from fig wasps (Chalcidoidea) to grizzly bears (Ursus arctos) exploit resource waves, integrating across phenological diversity to make resource aggregates available for much longer than their component parts. In model simulations, phenological diversity was often more important to consumer energy gain than resource abundance per se. Current ecosystem-based management assumes that species abundance mediates the strength of trophic interactions. Our results challenge this assumption and highlight new opportunities for conservation and management. Resource waves are an emergent property of consumer–resource interactions and are broadly significant in ecology and conservation.

  16. Evidence of the exploitation of marine resource by the terrestrial insect Scapteriscus didactylus through stable isotope analyzes of its cuticle.

    PubMed

    Maros, Alexandra; Louveaux, Alain; Lelarge, Caroline; Girondot, Marc

    2006-05-08

    About 4 x 10(5) eggs in more than 5000 marine turtle nests are deposited every year on a 3.6 km long beach in French Guiana (South America). The dry biomass of eggs is estimated to be 5 x 10(3) kg, yet only 25% of this organic matter will return to the ocean in the form of hatchlings. Such amounts of organic matter are supposed to drive the functioning of the beach ecosystem. Previous studies have shown that egg predators and detritivorous organisms dominate the trophic relationships and the dynamics of the system. The role of a terrestrial insect Scapteriscus didactylus (Latreille), which damages up to 40% of the eggs of the marine turtle (Dermochelys coriacea), was unexpected. However it was impossible from direct observations to prove that the mole cricket consumed a significant amount of these eggs. Therefore, the precise place of the mole cricket in the nitrogen and carbon cycles of the beach ecosystem could not be determined. In order to answer this question, we looked for a marine signature of carbon and nitrogen source metabolized by the mole cricket. This study estimated the individual variability of delta13C and delta15N in the cuticle of Scapteriscus didactylus. The isotopic signature was compared between individuals collected at two sites: a village where mole crickets fed on human food scraps and the nearby Awala-Yalimapo beach, where food availability depends seasonally on the nesting sea turtles. The mole crickets collected near the habitations garbage showed no significant variations in the stable isotopic signature, within-and between age groups. On the contrary, isotopic values shifted from a signature of a terrestrial herbivorous diet in the mole crickets during early developmental stages, to isotopic values in adults in accordance with the exploitation of marine animal resources. The heterogeneity of individual signatures during the year is due to a selective exploitation of the food sources, differing in space and time. Some individuals, from the beach sample consumed a sufficient quantity of turtle eggs to induce the increase of isotopic enrichment observed in the cuticle. Scapteriscus didactylus is an opportunist feeder and plays a role in the turn over of the beach organic matter.

  17. Evidence of the exploitation of marine resource by the terrestrial insect Scapteriscus didactylus through stable isotope analyzes of its cuticle

    PubMed Central

    Maros, Alexandra; Louveaux, Alain; Lelarge, Caroline; Girondot, Marc

    2006-01-01

    Background About 4 × 105 eggs in more than 5000 marine turtle nests are deposited every year on a 3.6 km long beach in French Guiana (South America). The dry biomass of eggs is estimated to be 5 × 103 kg, yet only 25% of this organic matter will return to the ocean in the form of hatchlings. Such amounts of organic matter are supposed to drive the functioning of the beach ecosystem. Previous studies have shown that egg predators and detritivorous organisms dominate the trophic relationships and the dynamics of the system. The role of a terrestrial insect Scapteriscus didactylus (Latreille), which damages up to 40% of the eggs of the marine turtle (Dermochelys coriacea), was unexpected. However it was impossible from direct observations to prove that the mole cricket consumed a significant amount of these eggs. Therefore, the precise place of the mole cricket in the nitrogen and carbon cycles of the beach ecosystem could not be determined. In order to answer this question, we looked for a marine signature of carbon and nitrogen source metabolized by the mole cricket. Results This study estimated the individual variability of δ13C and δ15N in the cuticle of Scapteriscus didactylus. The isotopic signature was compared between individuals collected at two sites: a village where mole crickets fed on human food scraps and the nearby Awala-Yalimapo beach, where food availability depends seasonally on the nesting sea turtles. The mole crickets collected near the habitations garbage showed no significant variations in the stable isotopic signature, within-and between age groups. On the contrary, isotopic values shifted from a signature of a terrestrial herbivorous diet in the mole crickets during early developmental stages, to isotopic values in adults in accordance with the exploitation of marine animal resources. Conclusion The heterogeneity of individual signatures during the year is due to a selective exploitation of the food sources, differing in space and time. Some individuals, from the beach sample consumed a sufficient quantity of turtle eggs to induce the increase of isotopic enrichment observed in the cuticle. Scapteriscus didactylus is an opportunist feeder and plays a role in the turn over of the beach organic matter. PMID:16681850

  18. The transition to foraging for dense and predictable resources and its impact on the evolution of modern humans.

    PubMed

    Marean, Curtis W

    2016-07-05

    Scientists have identified a series of milestones in the evolution of the human food quest that are anticipated to have had far-reaching impacts on biological, behavioural and cultural evolution: the inclusion of substantial portions of meat, the broad spectrum revolution and the transition to food production. The foraging shift to dense and predictable resources is another key milestone that had consequential impacts on the later part of human evolution. The theory of economic defendability predicts that this shift had an important consequence-elevated levels of intergroup territoriality and conflict. In this paper, this theory is integrated with a well-established general theory of hunter-gatherer adaptations and is used to make predictions for the sequence of appearance of several evolved traits of modern humans. The distribution of dense and predictable resources in Africa is reviewed and found to occur only in aquatic contexts (coasts, rivers and lakes). The palaeoanthropological empirical record contains recurrent evidence for a shift to the exploitation of dense and predictable resources by 110 000 years ago, and the first known occurrence is in a marine coastal context in South Africa. Some theory predicts that this elevated conflict would have provided the conditions for selection for the hyperprosocial behaviours unique to modern humans.This article is part of the themed issue 'Major transitions in human evolution'. © 2016 The Author(s).

  19. Discovery-dominance trade-off among widespread invasive ant species.

    PubMed

    Bertelsmeier, Cleo; Avril, Amaury; Blight, Olivier; Jourdan, Hervé; Courchamp, Franck

    2015-07-01

    Ants are among the most problematic invasive species. They displace numerous native species, alter ecosystem processes, and can have negative impacts on agriculture and human health. In part, their success might stem from a departure from the discovery-dominance trade-off that can promote co-existence in native ant communities, that is, invasive ants are thought to be at the same time behaviorally dominant and faster discoverers of resources, compared to native species. However, it has not yet been tested whether similar asymmetries in behavioral dominance, exploration, and recruitment abilities also exist among invasive species. Here, we establish a dominance hierarchy among four of the most problematic invasive ants (Linepithema humile, Lasius neglectus, Wasmannia auropunctata, Pheidole megacephala) that may be able to arrive and establish in the same areas in the future. To assess behavioral dominance, we used confrontation experiments, testing the aggressiveness in individual and group interactions between all species pairs. In addition, to compare discovery efficiency, we tested the species' capacity to locate a food resource in a maze, and the capacity to recruit nestmates to exploit a food resource. The four species differed greatly in their capacity to discover resources and to recruit nestmates and to dominate the other species. Our results are consistent with a discovery-dominance trade-off. The species that showed the highest level of interspecific aggressiveness and dominance during dyadic interactions.

  20. The transition to foraging for dense and predictable resources and its impact on the evolution of modern humans

    PubMed Central

    Marean, Curtis W.

    2016-01-01

    Scientists have identified a series of milestones in the evolution of the human food quest that are anticipated to have had far-reaching impacts on biological, behavioural and cultural evolution: the inclusion of substantial portions of meat, the broad spectrum revolution and the transition to food production. The foraging shift to dense and predictable resources is another key milestone that had consequential impacts on the later part of human evolution. The theory of economic defendability predicts that this shift had an important consequence—elevated levels of intergroup territoriality and conflict. In this paper, this theory is integrated with a well-established general theory of hunter–gatherer adaptations and is used to make predictions for the sequence of appearance of several evolved traits of modern humans. The distribution of dense and predictable resources in Africa is reviewed and found to occur only in aquatic contexts (coasts, rivers and lakes). The palaeoanthropological empirical record contains recurrent evidence for a shift to the exploitation of dense and predictable resources by 110 000 years ago, and the first known occurrence is in a marine coastal context in South Africa. Some theory predicts that this elevated conflict would have provided the conditions for selection for the hyperprosocial behaviours unique to modern humans. This article is part of the themed issue ‘Major transitions in human evolution’. PMID:27298470

  1. Food resource utilization of the skates Rioraja agassizii (Müller & Henle, 1841) and Psammobatis extenta (Garman, 1913) on the continental shelf off Ubatuba, South-eastern Brazil.

    PubMed

    Muto, E Y; Soares, L S; Goitein, R

    2001-05-01

    The feeding habits of Rioraja agassizii (syn. Raja agassizii) and Psammobatis extenta (syn. Psammobatis glansdissimilis) of the South-eastern Brazilian coast were studied by means of stomach content analysis. The samples were obtained on eight seasonal oceanographic cruises, carried out between October 1985 and July 1987. The importance of each food item was evaluated on the basis of the Index of Relative Importance and the feeding similarity by Percentage of Similarity. The results indicated that both species are benthic feeders, preying mainly on Crustacea, especially Amphipoda, Caridea and Brachyura. Teleostei were also important for R. agassizii. Seasonal variation of the diet seems to be associated with the availability of the prey, whose distribution and abundance are related to the dynamics of the water masses of the region. Juveniles and adults of P. extenta exploited the same resources while juveniles and adults of R. agassizii presented low diet similarity during most of the year. Caridea were an important food for all length classes of R. agassizii, while Amphipoda were for smaller specimens, and Teleostei for larger ones. The feeding overlap between the two species was higher during autumn 1986, winter 1986 and winter 1987.

  2. Aquaculture: a rapidly growing and significant source of sustainable food? Status, transitions and potential.

    PubMed

    Little, D C; Newton, R W; Beveridge, M C M

    2016-08-01

    The status and potential of aquaculture is considered as part of a broader food landscape of wild aquatic and terrestrial food sources. The rationale and resource base required for the development of aquaculture are considered in the context of broader societal development, cultural preferences and human needs. Attention is drawn to the uneven development and current importance of aquaculture globally as well as its considerable heterogeneity of form and function compared with established terrestrial livestock production. The recent drivers of growth in demand and production are examined and the persistent linkages between exploitation of wild stocks, full life cycle culture and the various intermediate forms explored. An emergent trend for sourcing aquaculture feeds from alternatives to marine ingredients is described and the implications for the sector with rapidly growing feed needs discussed. The rise of non-conventional and innovative feed ingredients, often shared with terrestrial livestock, are considered, including aquaculture itself becoming a major source of marine ingredients. The implications for the continued expected growth of aquaculture are set in the context of sustainable intensification, with the challenges that conventional intensification and emergent integration within, and between, value chains explored. The review concludes with a consideration of the implications for dependent livelihoods and projections for various futures based on limited resources but growing demand.

  3. Resource Exploitation and Consumption in the Frame of Education for Sustainable Development in German Geography Textbooks

    ERIC Educational Resources Information Center

    Kowasch, Matthias

    2017-01-01

    This paper discusses the representation of resource exploitation and consumption in German geography textbooks. The aim of the paper is to contribute to a critical and reflective understanding of the representation of resource-related issues in textbooks by analyzing two scientific debates (resource curse and actor analysis). The paper shows that…

  4. Estimates of sustainable agricultural water use in northern China based on the equilibrium of groundwater

    NASA Astrophysics Data System (ADS)

    Yali, Y.; Yu, C.

    2015-12-01

    The northern plain is the important food production region in China. However, due to the lack of surface water resources, it needs overmuch exploitation of groundwater to maintain water use in agriculture, which leads to serious environmental problems. Based on the assumption that the reserves of groundwater matches the statistics and keeps on stable, the author explores the reasonable agricultural water and its spatial distribution based on the principle of sustainable utilization of water resources. According to the priorities of water resources allocation (domestic water and ecological water>industrial water>agricultural water), it is proposed to reduce agricultural water use to balance the groundwater reserves on condition that the total water supply is constant. Method: Firstly, we calculate annual average of northern groundwater reserves changes from 2004 to 2010, which is regarded as the reduction of agricultural water; Then, we estimate the food production changes using variables of typical crop water requirements and unit yields assuming that the efficiency of water use keeps the same during the entire study period; Finally, we evaluate the usage of sustainable agricultural water. The results reveal that there is a significant reduction of groundwater reserves in Haihe river basin and Xinjiang oasis regions; And the annual loss of the corn and wheat production is about 1.86 billion kg and 700 million kg respectively due to the reduction of agricultural water; What's more, in order to ensure China's food security and sustainable agricultural water use, in addition to great efforts to develop water-saving agriculture, an important adjustment in the distribution of food production is in need. This study provided a basis to the availability of agricultural water and a new perspective was put forth for an estimation of agricultural water.

  5. Sex Trafficking of Minors.

    PubMed

    Moore, Jessica L; Kaplan, Dana M; Barron, Christine E

    2017-04-01

    Sex trafficking is an increasingly recognized global health crisis affecting every country and region in the world. Domestic minor sex trafficking is a subset of commercial sexual exploitation of children, defined as engagement of minors (<18 years of age) in sexual acts for items of value (eg, food, shelter, drugs, money) involving children victimized within US borders. These involved youth are at risk for serious immediate and long-term physical and mental health consequences. Continued efforts are needed to improve preventive efforts, identification, screening, appropriate interventions, and subsequent resource provision for victimized and high-risk youth. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Bioinformatics in the orphan crops.

    PubMed

    Armstead, Ian; Huang, Lin; Ravagnani, Adriana; Robson, Paul; Ougham, Helen

    2009-11-01

    Orphan crops are those which are grown as food, animal feed or other crops of some importance in agriculture, but which have not yet received the investment of research effort or funding required to develop significant public bioinformatics resources. Where an orphan crop is related to a well-characterised model plant species, comparative genomics and bioinformatics can often, though not always, be exploited to assist research and crop improvement. This review addresses some challenges and opportunities presented by bioinformatics in the orphan crops, using three examples: forage grasses from the genera Lolium and Festuca, forage legumes and the second generation energy crop Miscanthus.

  7. Body mass of prefledging Emperor Geese Chen canagica: Large-scale effects of interspecific densities and food availability

    USGS Publications Warehouse

    Lake, B.C.; Schmutz, J.A.; Lindberg, M.S.; Ely, Craig R.; Eldridge, W.D.; Broerman, F.J.

    2008-01-01

    We studied body mass of prefledging Emperor Geese Chen canagica at three locations across the Yukon-Kuskokwim Delta, Alaska, during 1990-2004 to investigate whether large-scale variation in body mass was related to interspecific competition for food. From 1990 to 2004, densities of Cackling Geese Branta hutchinsii minima more than doubled and were c. 2-5?? greater than densities of Emperor Geese, which were relatively constant over time. Body mass of prefledging Emperor Geese was strongly related (negatively) to interspecific densities of geese (combined density of Cackling and Emperor Geese) and positively related to measures of food availability (grazing lawn extent and net above-ground primary productivity (NAPP)). Grazing by geese resulted in consumption of ??? 90% of the NAPP that occurred in grazing lawns during the brood-rearing period, suggesting that density-dependent interspecific competition was from exploitation of common food resources. Efforts to increase the population size of Emperor Geese would benefit from considering competitive interactions among goose species and with forage plants. ?? 2008 The Authors.

  8. Unravelling rootstock×scion interactions to improve food security

    PubMed Central

    Albacete, Alfonso; Martínez-Andújar, Cristina; Martínez-Pérez, Ascensión; Thompson, Andrew J.; Dodd, Ian C.; Pérez-Alfocea, Francisco

    2015-01-01

    While much recent science has focused on understanding and exploiting root traits as new opportunities for crop improvement, the use of rootstocks has enhanced productivity of woody perennial crops for centuries. Grafting of vegetable crops has developed very quickly in the last 50 years, mainly to induce shoot vigour and to overcome soil-borne diseases in solanaceous and cucurbitaceous crops. In most cases, such progress has largely been due to empirical interactions between farmers, gardeners, and botanists, with limited insights into the underlying physiological mechanisms. Only during the last 20 years has science realized the potential of this old activity and studied the physiological and molecular mechanisms involved in rootstock×scion interactions, thereby not only explaining old phenomena but also developing new tools for crop improvement. Rootstocks can contribute to food security by: (i) increasing the yield potential of elite varieties; (ii) closing the yield gap under suboptimal growing conditions; (iii) decreasing the amount of chemical (pesticides and fertilizers) contaminants in the soil; (iv) increasing the efficiency of use of natural (water and soil) resources; (v) generating new useful genotypic variability (via epigenetics); and (vi) creating new products with improved quality. The potential of grafting is as broad as the genetic variability able to cross a potential incompatibility barrier between the rootstock and the scion. Therefore, understanding the mechanisms underlying the phenotypic variability resulting from rootstock×scion×environment interactions will certainly contribute to developing and exploiting rootstocks for food security. PMID:25754404

  9. Differential use of salmon by vertebrate consumers: implications for conservation

    PubMed Central

    Wheat, Rachel E.; Allen, Jennifer M.; Wilmers, Christopher C.

    2015-01-01

    Salmon and other anadromous fish are consumed by vertebrates with distinct life history strategies to capitalize on this ephemeral pulse of resource availability. Depending on the timing of salmon arrival, this resource may be in surplus to the needs of vertebrate consumers if, for instance, their populations are limited by food availability during other times of year. However, the life history of some consumers enables more efficient exploitation of these ephemeral resources. Bears can deposit fat and then hibernate to avoid winter food scarcity, and highly mobile consumers such as eagles, gulls, and other birds can migrate to access asynchronous pulses of salmon availability. We used camera traps on pink, chum, and sockeye salmon spawning grounds with various run times and stream morphologies, and on individual salmon carcasses, to discern potentially different use patterns among consumers. Wildlife use of salmon was highly heterogeneous. Ravens were the only avian consumer that fed heavily on pink salmon in small streams. Eagles and gulls did not feed on early pink salmon runs in streams, and only moderately at early sockeye runs, but were the dominant consumers at late chum salmon runs, particularly on expansive river flats. Brown bears used all salmon resources far more than other terrestrial vertebrates. Notably, black bears were not observed on salmon spawning grounds despite being the most frequently observed vertebrate on roads and trails. From a conservation and management perspective, all salmon species and stream morphologies are used extensively by bears, but salmon spawning late in the year are disproportionately important to eagles and other highly mobile species that are seasonally limited by winter food availability. PMID:26339539

  10. Interspecific resource partitioning in sympatric ursids

    USGS Publications Warehouse

    Belant, Jerrold L.; Kielland, Knut; Follmann, Erich H.; Adams, Layne G.

    2006-01-01

    The fundamental niche of a species is rarely if ever realized because the presence of other species restricts it to a narrower range of ecological conditions. The effects of this narrower range of conditions define how resources are partitioned. Resource partitioning has been inferred but not demonstrated previously for sympatric ursids. We estimated assimilated diet in relation to body condition (body fat and lean and total body mass) and reproduction for sympatric brown bears (Ursus arctos) and American black bears (U. americanus) in south‐central Alaska, 1998–2000. Based on isotopic analysis of blood and keratin in claws, salmon (Oncorhynchus spp.) predominated in brown bear diets (>53% annually) whereas black bears assimilated 0–25% salmon annually. Black bears did not exploit salmon during a year with below average spawning numbers, probably because brown bears deterred black bear access to salmon. Proportion of salmon in assimilated diet was consistent across years for brown bears and represented the major portion of their diet. Body size of brown bears in the study area approached mean body size of several coastal brown bear populations, demonstrating the importance of salmon availability to body condition. Black bears occurred at a comparable density (mass : mass), but body condition varied and was related directly to the amount of salmon assimilated in their diet. Both species gained most lean body mass during spring and all body fat during summer when salmon were present. Improved body condition (i.e., increased percentage body fat) from salmon consumption reduced catabolism of lean body mass during hibernation, resulting in better body condition the following spring. Further, black bear reproduction was directly related to body condition; reproductive rates were reduced when body condition was lower. High body fat content across years for brown bears was reflected in consistently high reproductive levels. We suggest that the fundamental niche of black bears was constrained by brown bears through partitioning of food resources, which varied among years. Reduced exploitation of salmon caused black bears to rely more extensively on less reliable or nutritious food sources (e.g., moose [Alces alces], berries) resulting in lowered body condition and subsequent reproduction.

  11. Key issues for determining the exploitable water resources in a Mediterranean river basin.

    PubMed

    Pedro-Monzonís, María; Ferrer, Javier; Solera, Abel; Estrela, Teodoro; Paredes-Arquiola, Javier

    2015-01-15

    One of the major difficulties in water planning is to determine the water availability in a water resource system in order to distribute water sustainably. In this paper, we analyze the key issues for determining the exploitable water resources as an indicator of water availability in a Mediterranean river basin. Historically, these territories are characterized by heavily regulated water resources and the extensive use of unconventional resources (desalination and wastewater reuse); hence, emulating the hydrological cycle is not enough. This analysis considers the Jucar River Basin as a case study. We have analyzed the different possible combinations between the streamflow time series, the length of the simulation period and the reliability criteria. As expected, the results show a wide dispersion, proving the great influence of the reliability criteria used for the quantification and localization of the exploitable water resources in the system. Therefore, it is considered risky to provide a single value to represent the water availability in the Jucar water resource system. In this sense, it is necessary that policymakers and stakeholders make a decision about the methodology used to determine the exploitable water resources in a river basin. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Investigating competing uses of unevenly distributed resources in Nicaragua applying the Climate, Land Use (Food), Energy and Water strategies framework

    NASA Astrophysics Data System (ADS)

    Ramos, Eunice; Sridharan, Vignesh; Howells, Mark

    2017-04-01

    The distribution of resources in Nicaragua is not even, as it is the case in many countries in the world. However, in the particular case of water resources, commonly used by different sectors and essential to basic human activities, their availability differs along the main drainage basins and is often mismatched with sectoral demands. For example, the population is distributed unevenly, with 80% being located in water scarce areas of the Pacific and Central region of Nicaragua. Agricultural activities also take place in regions where water resources are vulnerable. The spatial distribution of water and energy resources, population and land use in Nicaragua allowed for the identification of three target regions for the analysis: the Pacific coast, the Dry Corridor zone, and the Atlantic region. Each of these zones has different challenges on which the CLEWs assessment focused on. Water sources in the Pacific coast are mostly groundwater, and uncertainty exists related to the long-term availability of such source. This is also the region where most of the sugarcane, an important source of revenue for Nicaragua, is produced. As sugarcane needs to be irrigated, this increases the pressure on water resources. The Dry Corridor is an arid stretch in Central America cyclically affected by droughts that have a severe impact on the households whose economy and subsistence depends on agriculture of grains and coffee beans. It is expected that climate change will exacerbate further the food security problem. When water is lacking, also population experiences limited access to water for drinking and cooking. In addition, two major hydropower plants are located in this zone. Water resources are available both from surface and groundwater sources, however, due to their intensive use and vulnerability to climate, their availability can affect severely different sectors, presenting risks to food, water and energy security. Hydropower potential is foreseen to be exploited in the Matagalpa and Escondido River Basins draining to the Atlantic Ocean. Although competition for water resources in not as acute as in other regions due to abundant surface water and lower population density, climate change and the use of land for grazing could present risks to the exploitation of the renewable energy potential. This could have an impact on medium and long-term energy planning and the ambition of decreasing fuel imports for electricity generation and increase electricity access. To assess the potential implications of the previous challenges and provide insights on solutions where conflicts are more stringent, in line with sustainable development priorities, the CLEWs framework was used to perform the integration of resource systems models. WEAP was used for the representation of the water and land use systems, and then soft-linked with the energy systems model for Nicaragua, developed using the long-term energy planning tool OSeMOSYS. Hydropower expansion, the development of the electricity system, water availability for crop production, water allocation across sectors, sugarcane cultivation and bi-products use in electricity generation, and potential impacts of climate change, are amongst the issues investigated with the region-specific scenarios defined for the study.

  13. The broad spectrum revisited: Evidence from plant remains

    PubMed Central

    Weiss, Ehud; Wetterstrom, Wilma; Nadel, Dani; Bar-Yosef, Ofer

    2004-01-01

    The beginning of agriculture is one of the most important developments in human history, with enormous consequences that paved the way for settled life and complex society. Much of the research on the origins of agriculture over the last 40 years has been guided by Flannery's [Flannery, K. V. (1969) in The Domestication and Exploitation of Plants and Animals, eds. Ucko, P. J. & Dimbleby, G. W. (Duckworth, London), pp. 73–100] “broad spectrum revolution” (BSR) hypothesis, which posits that the transition to farming in southwest Asia entailed a period during which foragers broadened their resource base to encompass a wide array of foods that were previously ignored in an attempt to overcome food shortages. Although these resources undoubtedly included plants, nearly all BSR hypothesis-inspired research has focused on animals because of a dearth of Upper Paleolithic archaeobotanical assemblages. Now, however, a collection of >90,000 plant remains, recently recovered from the Stone Age site Ohalo II (23,000 B.P.), Israel, offers insights into the plant foods of the late Upper Paleolithic. The staple foods of this assemblage were wild grasses, pushing back the dietary shift to grains some 10,000 years earlier than previously recognized. Besides the cereals (wild wheat and barley), small-grained grasses made up a large component of the assemblage, indicating that the BSR in the Levant was even broader than originally conceived, encompassing what would have been low-ranked plant foods. Over the next 15,000 years small-grained grasses were gradually replaced by the cereals and ultimately disappeared from the Levantine diet. PMID:15210984

  14. The broad spectrum revisited: evidence from plant remains.

    PubMed

    Weiss, Ehud; Wetterstrom, Wilma; Nadel, Dani; Bar-Yosef, Ofer

    2004-06-29

    The beginning of agriculture is one of the most important developments in human history, with enormous consequences that paved the way for settled life and complex society. Much of the research on the origins of agriculture over the last 40 years has been guided by Flannery's [Flannery, K. V. (1969) in The Domestication and Exploitation of Plants and Animals, eds. Ucko, P. J. & Dimbleby, G. W. (Duckworth, London), pp. 73-100] "broad spectrum revolution" (BSR) hypothesis, which posits that the transition to farming in southwest Asia entailed a period during which foragers broadened their resource base to encompass a wide array of foods that were previously ignored in an attempt to overcome food shortages. Although these resources undoubtedly included plants, nearly all BSR hypothesis-inspired research has focused on animals because of a dearth of Upper Paleolithic archaeobotanical assemblages. Now, however, a collection of >90,000 plant remains, recently recovered from the Stone Age site Ohalo II (23,000 B.P.), Israel, offers insights into the plant foods of the late Upper Paleolithic. The staple foods of this assemblage were wild grasses, pushing back the dietary shift to grains some 10,000 years earlier than previously recognized. Besides the cereals (wild wheat and barley), small-grained grasses made up a large component of the assemblage, indicating that the BSR in the Levant was even broader than originally conceived, encompassing what would have been low-ranked plant foods. Over the next 15,000 years small-grained grasses were gradually replaced by the cereals and ultimately disappeared from the Levantine diet.

  15. Traditional uses of plants in a rural community of Mozambique and possible links with Miombo degradation and harvesting sustainability

    PubMed Central

    2014-01-01

    Background Miombo woodlands play an important role in the livelihood of people living in sub-equatorial African countries, contributing to satisfy basic human needs such as food, medicine, fuelwood and building materials. However, over-exploitation of plant resources and unsustainable harvest practices can potentially degrade forests. The aim of this study was to document the use of Miombo plant products, other than medicinal plants, in local communities, within a wider framework in which we discussed possible links between traditional uses and conservation status of the used species and of the whole Miombo environment. Methods Fieldwork took place in four communities of Muda-Serração, central Mozambique. We conducted semi-structured interviews with 52 informants about their knowledge, use and harvesting practices of useful plants. A survey on local Miombo vegetation was also carried out in order to assess abundance and distribution of useful woody plants cited in the interviews in areas exposed to different exploitation rates. A Conservation Priority index was also applied to rank conservation values of each used woody species. Results Ninety-eight plants cited by the informants were botanically identified. The most relevant general category was represented by food plants (45 species), followed by handicraft plants (38 species) and domestic plants (37 species). Among the 54 woody species observed in vegetation plots, 52% were cited as useful in the interviews. Twenty-six woody species found in ‘natural’ Miombo areas were not found in ‘degraded’ ones: of these, 46% were cited in the interviews (58% in the food category, 50% in the handicraft category, 25% in the domestic category and 8% in the fishing category). Results of conservation ranking showed that 7 woody species deserve conservation priority in the investigated area. Conclusions This study shows that the communities investigated rely heavily on local forest products for their daily subsistence requirements in food, firewood/charcoal and building materials. However, over-exploitation and destructive collection seem to threaten the survival of some of the woody species used. A sustainable approach including the involvement of local communities in the management of woody species is recommended. PMID:25056487

  16. Traditional uses of plants in a rural community of Mozambique and possible links with Miombo degradation and harvesting sustainability.

    PubMed

    Bruschi, Piero; Mancini, Matteo; Mattioli, Elisabetta; Morganti, Michela; Signorini, Maria Adele

    2014-07-23

    Miombo woodlands play an important role in the livelihood of people living in sub-equatorial African countries, contributing to satisfy basic human needs such as food, medicine, fuelwood and building materials. However, over-exploitation of plant resources and unsustainable harvest practices can potentially degrade forests. The aim of this study was to document the use of Miombo plant products, other than medicinal plants, in local communities, within a wider framework in which we discussed possible links between traditional uses and conservation status of the used species and of the whole Miombo environment. Fieldwork took place in four communities of Muda-Serração, central Mozambique. We conducted semi-structured interviews with 52 informants about their knowledge, use and harvesting practices of useful plants. A survey on local Miombo vegetation was also carried out in order to assess abundance and distribution of useful woody plants cited in the interviews in areas exposed to different exploitation rates. A Conservation Priority index was also applied to rank conservation values of each used woody species. Ninety-eight plants cited by the informants were botanically identified. The most relevant general category was represented by food plants (45 species), followed by handicraft plants (38 species) and domestic plants (37 species). Among the 54 woody species observed in vegetation plots, 52% were cited as useful in the interviews. Twenty-six woody species found in 'natural' Miombo areas were not found in 'degraded' ones: of these, 46% were cited in the interviews (58% in the food category, 50% in the handicraft category, 25% in the domestic category and 8% in the fishing category). Results of conservation ranking showed that 7 woody species deserve conservation priority in the investigated area. This study shows that the communities investigated rely heavily on local forest products for their daily subsistence requirements in food, firewood/charcoal and building materials. However, over-exploitation and destructive collection seem to threaten the survival of some of the woody species used. A sustainable approach including the involvement of local communities in the management of woody species is recommended.

  17. Hypoxic areas, density-dependence and food limitation drive the body condition of a heavily exploited marine fish predator

    PubMed Central

    Käll, Filip; Hansson, Martin; Baranova, Tatjana; Karlsson, Olle; Lundström, Karl; Neuenfeldt, Stefan; Hjelm, Joakim

    2016-01-01

    Investigating the factors regulating fish condition is crucial in ecology and the management of exploited fish populations. The body condition of cod (Gadus morhua) in the Baltic Sea has dramatically decreased during the past two decades, with large implications for the fishery relying on this resource. Here, we statistically investigated the potential drivers of the Baltic cod condition during the past 40 years using newly compiled fishery-independent biological data and hydrological observations. We evidenced a combination of different factors operating before and after the ecological regime shift that occurred in the Baltic Sea in the early 1990s. The changes in cod condition related to feeding opportunities, driven either by density-dependence or food limitation, along the whole period investigated and to the fivefold increase in the extent of hypoxic areas in the most recent 20 years. Hypoxic areas can act on cod condition through different mechanisms related directly to species physiology, or indirectly to behaviour and trophic interactions. Our analyses found statistical evidence for an effect of the hypoxia-induced habitat compression on cod condition possibly operating via crowding and density-dependent processes. These results furnish novel insights into the population dynamics of Baltic Sea cod that can aid the management of this currently threatened population. PMID:27853557

  18. The effects of facilitation and competition on group foraging in patches

    PubMed Central

    Laguë, Marysa; Tania, Nessy; Heath, Joel; Edelstein-Keshet, Leah

    2012-01-01

    Significant progress has been made towards understanding the social behaviour of animal groups, but the patch model, a foundation of foraging theory, has received little attention in a social context. The effect of competition on the optimal time to leave a foraging patch was considered as early as the original formulation of the marginal value theorem, but surprisingly, the role of facilitation (where foraging in groups decreases the time to find food in patches), has not been incorporated. Here we adapt the classic patch model to consider how the trade-off between facilitation and competition influence optimal group size. Using simple assumptions about the effect of group size on the food-finding time and the sharing of resources, we find conditions for existence of optima in patch residence time and in group size. When patches are close together (low travel times), larger group sizes are optimal. Groups are predicted to exploit patches differently than individual foragers and the degree of patch depletion at departure depends on the details of the trade-off between competition and facilitation. A variety of currencies and group-size effects are also considered and compared. Using our simple formulation, we also study the effects of social foraging on patch exploitation which to date have received little empirical study. PMID:22743132

  19. The effects of facilitation and competition on group foraging in patches.

    PubMed

    Laguë, Marysa; Tania, Nessy; Heath, Joel; Edelstein-Keshet, Leah

    2012-10-07

    Significant progress has been made towards understanding the social behaviour of animal groups, but the patch model, a foundation of foraging theory, has received little attention in a social context. The effect of competition on the optimal time to leave a foraging patch was considered as early as the original formulation of the marginal value theorem, but surprisingly, the role of facilitation (where foraging in groups decreases the time to find food in patches), has not been incorporated. Here we adapt the classic patch model to consider how the trade-off between facilitation and competition influences optimal group size. Using simple assumptions about the effect of group size on the food-finding time and the sharing of resources, we find conditions for existence of optima in patch residence time and in group size. When patches are close together (low travel times), larger group sizes are optimal. Groups are predicted to exploit patches differently than individual foragers and the degree of patch depletion at departure depends on the details of the trade-off between competition and facilitation. A variety of currencies and group-size effects are also considered and compared. Using our simple formulation, we also study the effects of social foraging on patch exploitation which to date have received little empirical study. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Altered epiphyte community and sea urchin diet in Posidonia oceanica meadows in the vicinity of volcanic CO2 vents.

    PubMed

    Nogueira, Patricia; Gambi, Maria Cristina; Vizzini, Salvatrice; Califano, Gianmaria; Tavares, Ana Mafalda; Santos, Rui; Martínez-Crego, Begoña

    2017-06-01

    Ocean acidification (OA) predicted for 2100 is expected to shift seagrass epiphyte communities towards the dominance of more tolerant non-calcifying taxa. However, little is known about the indirect effects of such changes on food provision to key seagrass consumers. We found that epiphyte communities of the seagrass Posidonia oceanica in two naturally acidified sites (i.e. north and south sides of a volcanic CO 2 vent) and in a control site away from the vent at the Ischia Island (NW Mediterranean Sea) significantly differed in composition and abundance. Such differences involved a higher abundance of non-calcareous crustose brown algae and a decline of calcifying polychaetes in both acidified sites. A lower epiphytic abundance of crustose coralline algae occurred only in the south side of the vents, thus suggesting that OA may alter epiphyte assemblages in different ways due to interaction with local factors such as differential fish herbivory or hydrodynamics. The OA effects on food items (seagrass, epiphytes, and algae) indirectly propagated into food provision to the sea urchin Paracentrotus lividus, as reflected by a reduced P. oceanica exploitation (i.e. less seagrass and calcareous epiphytes in the diet) in favour of non-calcareous green algae in both vent sites. In contrast, we detected no difference close and outside the vents neither in the composition of sea urchin diet nor in the total abundance of calcareous versus non-calcareous taxa. More research, under realistic scenarios of predicted pH reduction (i.e. ≤ 0.32 units of pH by 2100), is still necessary to better understand cascading effects of this altered urchin exploitation of food resources under acidified conditions on ecosystem diversity and function. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Composite collective decision-making

    PubMed Central

    Czaczkes, Tomer J.; Czaczkes, Benjamin; Iglhaut, Carolin; Heinze, Jürgen

    2015-01-01

    Individual animals are adept at making decisions and have cognitive abilities, such as memory, which allow them to hone their decisions. Social animals can also share information. This allows social animals to make adaptive group-level decisions. Both individual and collective decision-making systems also have drawbacks and limitations, and while both are well studied, the interaction between them is still poorly understood. Here, we study how individual and collective decision-making interact during ant foraging. We first gathered empirical data on memory-based foraging persistence in the ant Lasius niger. We used these data to create an agent-based model where ants may use social information (trail pheromones), private information (memories) or both to make foraging decisions. The combined use of social and private information by individuals results in greater efficiency at the group level than when either information source was used alone. The modelled ants couple consensus decision-making, allowing them to quickly exploit high-quality food sources, and combined decision-making, allowing different individuals to specialize in exploiting different resource patches. Such a composite collective decision-making system reaps the benefits of both its constituent parts. Exploiting such insights into composite collective decision-making may lead to improved decision-making algorithms. PMID:26019155

  2. Wild capuchin monkeys (Cebus libidinosus) use anvils and stone pounding tools.

    PubMed

    Fragaszy, Dorothy; Izar, Patrícia; Visalberghi, Elisabetta; Ottoni, Eduardo B; de Oliveira, Marino Gomes

    2004-12-01

    We conducted an exploratory investigation in an area where nut-cracking by wild capuchin monkeys is common knowledge among local residents. In addition to observing male and female capuchin monkeys using stones to pound open nuts on stone "anvils," we surveyed the surrounding area and found physical evidence that monkeys cracked nuts on rock outcrops, boulders, and logs (collectively termed anvils). Anvils, which were identified by numerous shallow depressions on the upper surface, the presence of palm shells and debris, and the presence of loose stones of an appropriate size to pound nuts, were present even on the tops of mesas. The stones used to crack nuts can weigh >1 kg, and are remarkably heavy for monkeys that weigh <4 kg. The abundance of shell remains and depressions in the anvil surface at numerous anvil sites indicate that nut-cracking activity is common and long-enduring. Many of the stones found on anvils (presumably used to pound nuts) are river pebbles that are not present in the local area we surveyed (except on or near the anvils); therefore, we surmise that they were transported to the anvil sites. Ecologically and behaviorally, nut-cracking by capuchins appears to have strong parallels to nut-cracking by wild chimpanzees. The presence of abundant anvil sites, limited alternative food resources, abundance of palms, and the habit of the palms in this region to produce fruit at ground level all likely contribute to the monkeys' routine exploitation of palm nuts via cracking them with stones. This discovery provides a new reference point for discussions regarding the evolution of tool use and material culture in primates. Routine tool use to exploit keystone food resources is not restricted to living great apes and ancestral hominids. Copyright 2004 Wiley-Liss, Inc.

  3. Balancing the Budget through Social Exploitation: Why Hard Times Are Even Harder for Some.

    PubMed

    Tropman, John; Nicklett, Emily

    2012-01-01

    In all societies needs and wants regularly exceed resources. Thus societies are always in deficit; demand always exceeds supply and "balancing the budget" is a constant social problem. To make matters somewhat worse, research suggests that need- and want-fulfillment tends to further stimulate the cycle of wantseeking rather than satiating desire. Societies use various resource-allocation mechanisms, including price, to cope with gaps between wants and resources. Social exploitation is a second mechanism, securing labor from population segments that can be coerced or convinced to perform necessary work for free or at below-market compensation. Using practical examples, this article develops a theoretical framework for understanding social exploitation. It then offers case examples of how different segments of the population emerge as exploited groups in the United States, due to changes in social policies. These exploitative processes have been exacerbated and accelerated by the economic downturn that began in 2007.

  4. Ecological generalism and behavioural innovation in birds: technical intelligence or the simple incorporation of new foods?

    PubMed

    Ducatez, Simon; Clavel, Joanne; Lefebvre, Louis

    2015-01-01

    Generalist species are more successful than specialists in anthropogenically modified environments or in environments in which they have been introduced, but the nature of the link between generalism and establishment success is unclear. A higher feeding innovation rate has previously been reported in habitat generalist birds from North America. By allowing them to exploit new resources, this higher feeding innovation rate might explain the generalists' advantage. This result might be due to generalists being more likely to find new resources because they are exposed to more diverse environmental conditions. Alternatively, they might differ from specialists in other traits, in particular cognitive skills that might allow them to innovate more complex food searching and handling techniques. To test these hypotheses, we separated avian feeding innovations into a 'technical' (novel searching and handling behaviour) and a 'food type' (incorporation of a new food in a species' diet) category. Technical innovations, but not food type innovations, have previously been shown to correlate with avian brain size, suggesting they reflect cognitive ability. We used a world-wide data base of 2339 feeding innovations recorded in the literature, covering a total of 765 avian species and assessed the correlations between brain size and feeding innovation rates on one side and habitat and diet generalism on the other. Habitat generalism was positively related with food type innovation rate, but not technical innovation rate or brain size. This suggests that habitat generalist species are more likely to incorporate new food types in their diet because of higher chances to find new food resources in their environment, or of a higher opportunism, but not enhanced cognitive skills. In contrast, diet generalist species had higher food type and technical innovation rates, as well as larger brains, suggesting that cognitive skills might help species expand their diet breadth or that an increase in diet breadth might favour the evolution of enhanced cognitive abilities. Our results provide new insights into the nature of the generalists' advantage in the face of environmental changes, and suggest that dietary and habitat generalism are different, but convergent, routes to feeding flexibility and adaptation to changed environments. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

  5. How Jordan and Saudi Arabia are avoiding a tragedy of the commons over shared groundwater

    NASA Astrophysics Data System (ADS)

    Müller, Marc F.; Müller-Itten, Michèle C.; Gorelick, Steven M.

    2017-07-01

    Transboundary aquifers are ubiquitous and strategically important to global food and water security. Yet these shared resources are being depleted at an alarming rate. Focusing on the Disi aquifer, a key nonrenewable source of groundwater shared by Jordan and Saudi Arabia, this study develops a two-stage game that evaluates optimal transboundary strategies of common-pool resource exploitation under various assumptions. The analysis relies on estimates of agricultural water use from satellite imagery, which were obtained using three independent remote sensing approaches. Drawdown response to pumping is simulated using a 2-D regional aquifer model. Jordan and Saudi Arabia developed a buffer-zone strategy with a prescribed minimum distance between each country's pumping centers. We show that by limiting the marginal impact of pumping decisions on the other country's pumping costs, this strategy will likely avoid an impeding tragedy of the commons for at least 60 years. Our analysis underscores the role played by distance between wells and disparities in groundwater exploitation costs on common-pool overdraft. In effect, if pumping centers are distant enough, a shared aquifer no longer behaves as a common-pool resource and a tragedy of the commons can be avoided. The 2015 Disi aquifer pumping agreement between Jordan and Saudi Arabia, which in practice relies on a joint technical commission to enforce exclusion zones, is the first agreement of this type between sovereign countries and has a promising potential to avoid conflicts or resolve potential transboundary groundwater disputes over comparable aquifer systems elsewhere.

  6. Exploit and ignore the consequences: A mother of planetary issues.

    PubMed

    Moustafa, Khaled

    2016-07-01

    Many environmental and planetary issues are due to an exploitation strategy based on exploit, consume and ignore the consequences. As many natural and environmental resources are limited in time and space, such exploitation approach causes important damages on earth, in the sea and maybe soon in the space. To sustain conditions under which humans and other living species can coexist in productive and dynamic harmony with their environments, terrestrial and space exploration programs may need to be based on 'scrutinize the consequences, prepare adequate solutions and then, only then, exploit'. Otherwise, the exploitation of planetary resources may put the environmental stability and sustainability at a higher risk than it is currently predicted. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Exploit and ignore the consequences: A mother of planetary issues

    NASA Astrophysics Data System (ADS)

    Moustafa, K.

    2016-07-01

    Many environmental and planetary issues are due to an exploitation strategy based on exploit, consume and ignore the consequences. As many natural and environmental resources are limited in time and space, such exploitation approach causes important damages on earth, in the sea and maybe soon in the space. To sustain conditions under which humans and other living species can coexist in productive and dynamic harmony with their environments, terrestrial and space exploration programs may need to be based on 'scrutinize the consequences, prepare adequate solutions and then, only then, exploit'. Otherwise, the exploitation of planetary resources may put the environmental stability and sustainability at a higher risk than it is currently predicted. (C) 2016 Elsevier B.V. All rights reserved.

  8. Effects of Behavioural Strategy on the Exploitative Competition Dynamics.

    PubMed

    Nguyen-Ngoc, Doanh; Nguyen-Phuong, Thuy

    2016-12-01

    We investigate a system of two species exploiting a common resource. We consider both abiotic (i.e. with a constant resource supply rate) and biotic (i.e. with resource reproduction and self-limitation) resources. We are interested in the asymmetric competition where a given consumer is the locally superior resource exploiter (LSE) and the other is the locally inferior resource exploiter (LIE). They also interact directly via interference competition in the sense that LIE individuals can use two opposite strategies to compete with LSE individuals: we assume, in the first case, that LIE uses an avoiding strategy, i.e. LIE individuals go to a non-competition patch to avoids competition with LSE individuals, and in the second one, LIE uses an aggressive strategy, i.e. being very aggressive so that LSE individuals have to go to a non-competition patch. We further assume that there is no resource in the non-competition patch so that individuals have to come back to the competition patch for their maintenance, and the migration process acts on a fast time scale in comparison with demography and competition processes. The models show that being aggressive is efficient for LIE's survival and even provoke global extinction of the LSE and this result does not depend on the nature of resource.

  9. Inland capture fisheries

    PubMed Central

    Welcomme, Robin L.; Cowx, Ian G.; Coates, David; Béné, Christophe; Funge-Smith, Simon; Halls, Ashley; Lorenzen, Kai

    2010-01-01

    The reported annual yield from inland capture fisheries in 2008 was over 10 million tonnes, although real catches are probably considerably higher than this. Inland fisheries are extremely complex, and in many cases poorly understood. The numerous water bodies and small rivers are inhabited by a wide range of species and several types of fisher community with diversified livelihood strategies for whom inland fisheries are extremely important. Many drivers affect the fisheries, including internal fisheries management practices. There are also many drivers from outside the fishery that influence the state and functioning of the environment as well as the social and economic framework within which the fishery is pursued. The drivers affecting the various types of inland water, rivers, lakes, reservoirs and wetlands may differ, particularly with regard to ecosystem function. Many of these depend on land-use practices and demand for water which conflict with the sustainability of the fishery. Climate change is also exacerbating many of these factors. The future of inland fisheries varies between continents. In Asia and Africa the resources are very intensely exploited and there is probably little room for expansion; it is here that resources are most at risk. Inland fisheries are less heavily exploited in South and Central America, and in the North and South temperate zones inland fisheries are mostly oriented to recreation rather than food production. PMID:20713391

  10. From metabolism to ecology: cross-feeding interactions shape the balance between polymicrobial conflict and mutualism

    PubMed Central

    Estrela, Sylvie; Trisos, Christopher H.; Brown, Sam P.

    2012-01-01

    Polymicrobial interactions are widespread in nature, and play a major role in maintaining human health and ecosystems. Whenever one organism uses metabolites produced by another organism as energy or nutrient sources, this is called cross-feeding. The ecological outcomes of cross-feeding interactions are poorly understood and potentially diverse: mutualism, competition, exploitation or commensalism. A major reason for this uncertainty is the lack of theoretical approaches linking microbial metabolism to microbial ecology. To address this issue, we explore the dynamics of a one-way interspecific cross-feeding interaction, in which food can be traded for a service (detoxification). Our results show that diverse ecological interactions (competition, mutualism, exploitation) can emerge from this simple cross-feeding interaction, and can be predicted by the metabolic, demographic and environmental parameters that govern the balance of the costs and benefits of association. In particular, our model predicts stronger mutualism for intermediate by-product toxicity because the resource-service exchange is constrained to the service being neither too vital (high toxicity impairs resource provision) nor dispensable (low toxicity reduces need for service). These results support the idea that bridging microbial ecology and metabolism is a critical step towards a better understanding of the factors governing the emergence and dynamics of polymicrobial interactions. PMID:23070318

  11. Biodesalination: A Case Study for Applications of Photosynthetic Bacteria in Water Treatment1[C

    PubMed Central

    Amezaga, Jaime M.; Amtmann, Anna; Biggs, Catherine A.; Bond, Tom; Gandy, Catherine J.; Honsbein, Annegret; Karunakaran, Esther; Lawton, Linda; Madsen, Mary Ann; Minas, Konstantinos; Templeton, Michael R.

    2014-01-01

    Shortage of freshwater is a serious problem in many regions worldwide, and is expected to become even more urgent over the next decades as a result of increased demand for food production and adverse effects of climate change. Vast water resources in the oceans can only be tapped into if sustainable, energy-efficient technologies for desalination are developed. Energization of desalination by sunlight through photosynthetic organisms offers a potential opportunity to exploit biological processes for this purpose. Cyanobacterial cultures in particular can generate a large biomass in brackish and seawater, thereby forming a low-salt reservoir within the saline water. The latter could be used as an ion exchanger through manipulation of transport proteins in the cell membrane. In this article, we use the example of biodesalination as a vehicle to review the availability of tools and methods for the exploitation of cyanobacteria in water biotechnology. Issues discussed relate to strain selection, environmental factors, genetic manipulation, ion transport, cell-water separation, process design, safety, and public acceptance. PMID:24610748

  12. Regional groundwater flow modeling of the Geba basin, northern Ethiopia

    NASA Astrophysics Data System (ADS)

    Gebreyohannes, Tesfamichael; De Smedt, Florimond; Walraevens, Kristine; Gebresilassie, Solomon; Hussien, Abdelwassie; Hagos, Miruts; Amare, Kassa; Deckers, Jozef; Gebrehiwot, Kindeya

    2017-05-01

    The Geba basin is one of the most food-insecure areas of the Tigray regional state in northern Ethiopia due to recurrent drought resulting from erratic distribution of rainfall. Since the beginning of the 1990s, rain-fed agriculture has been supported through small-scale irrigation schemes mainly by surface-water harvesting, but success has been limited. Hence, use of groundwater for irrigation purposes has gained considerable attention. The main purpose of this study is to assess groundwater resources in the Geba basin by means of a MODFLOW modeling approach. The model is calibrated using observed groundwater levels, yielding a clear insight into the groundwater flow systems and reserves. Results show that none of the hydrogeological formations can be considered as aquifers that can be exploited for large-scale groundwater exploitation. However, aquitards can be identified that can support small-scale groundwater abstraction for irrigation needs in regions that are either designated as groundwater discharge areas or where groundwater levels are shallow and can be tapped by hand-dug wells or shallow boreholes.

  13. Nanobiotechnology for the Environment: Innovative Solutions for the Management of Harmful Algal Blooms.

    PubMed

    Gellert, Matthew R; Kim, Beum Jun; Reffsin, Samuel E; Jusuf, Sebastian E; Wagner, Nicole D; Winans, Stephen C; Wu, Mingming

    2017-12-04

    Nanobiotechnology has played important roles in solving contemporary health problems, including cancer and diabetes, but has not yet been widely exploited for problems in food security and environmental protection. Water scarcity is an emerging worldwide problem as a result of climate change and population increase. Current methods of managing water resources are not efficient or sustainable. In this perspective, we focus on harmful algal blooms to demonstrate how nanobiotechnology can be explored to understand microbe-environment interactions and allow for toxin/pollutant detection with significantly improved sensitivity. These capabilities hold potential for future development of sustainable solutions for drinking water management.

  14. Nutrition, modernity and the archaeological record: coastal resources and nutrition among Middle Stone Age hunter-gatherers on the Western Cape coast of South Africa.

    PubMed

    Kyriacou, Katharine; Parkington, John E; Marais, Adrian D; Braun, David R

    2014-12-01

    In this paper, we assess the nutritional value of some marine and terrestrial food resources available to Middle Stone Age hunter-gatherers in the Western Cape of South Africa with respect to an important macronutrient (protein) and an essential micronutrient (iron) and introduce a framework for assessing the relative utility of marine and terrestrial resources. Whilst the ability to extract nutrients from the environment has always been a lynchpin in archaeologists' reconstructions of human evolution, a recent paradigm shift has recognized the role of marine resources in encephalization. Nutritional research indicates that marine ecosystems are the best source for long chain polyunsaturated fatty acids essential for proper brain development, and excavations at securely dated archaeological sites in South Africa provide firm evidence for the exploitation of marine resources by Middle Stone Age hunter-gatherers from at least Marine Isotope Stage 5 (130 ka), and possibly even earlier. Because marine molluscs are abundant, predictably located and easily harvested, they would have been readily available to all members of the community, in contrast to terrestrial resources. The improving archaeological record gives important clues to resource choice, but many more nutritional observations are needed to determine the extent to which marine resources could have met the nutrient requirements of prehistoric people. Our observations indicate that marine and terrestrial fauna are both excellent sources of protein, and that marine molluscs have higher iron concentrations than we expected for invertebrate fauna. We calculate the number of individual food items from a selection of marine and terrestrial species needed to provide the protein and iron requirements of a hypothetical group of hunter-gatherers, identify contrasts in peoples' requirements for and access to nutrients and resources, and discuss the implications for prehistoric subsistence strategies and human evolution. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Multi-objective optimization for conjunctive water use using coupled hydrogeological and agronomic models: a case study in Heihe mid-reach (China)

    NASA Astrophysics Data System (ADS)

    LI, Y.; Kinzelbach, W.; Pedrazzini, G.

    2017-12-01

    Groundwater is a vital water resource to buffer unexpected drought risk in agricultural production, which is however apt to unsustainable exploitation due to its open access characteristic and a much underestimated marginal cost. Being a wicked problem of general water resource management, groundwater staying hidden from surface terrain further amplifies difficulties of management. China has been facing this challenge in last decades, particularly in the northern part where irrigated agriculture resides despite of scarce surface water available compared to the south. Farmers therefore have been increasingly exploiting groundwater as an alternative in order to reach Chinese food self-sufficiency requirements and feed fast socio-economic development. In this work, we studied Heihe mid-reach located in northern China, which represents one of a few regions suffering from symptoms of unsustainable groundwater use, such as a large drawdown of the groundwater table in some irrigation districts, or soil salinization due to phreatic evaporation in others. In addition, we focus on solving a multi-objective optimization problem of conjunctive water use in order to find an alternative management scheme that fits decision makers' preference. The methodology starts with a global sensitivity analysis to determine the most influential decision variables. Then a state-of-the-art multi-objective evolutionary algorithm (MOEA) is employed to search a hyper-dimensional Pareto Front. The aquifer system is simulated with a distributed Modflow model, which is able to capture the main phenomenon of interest. Results show that the current water allocation scheme seems to exploit the water resources in an inefficient way, where areas with depression cones and areas with salinization or groundwater table rise can both be mitigated with an alternative management scheme. When assuming uncertain boundary conditions according to future climate change, the optimal solutions can yield better performance in economical productivity by reducing opportunity cost under unexpected drought conditions.

  16. An ecology-oriented exploitation mode of groundwater resources in the northern Tianshan Mountains, China

    NASA Astrophysics Data System (ADS)

    Shang, Haimin; Wang, Wenke; Dai, Zhenxue; Duan, Lei; Zhao, Yaqian; Zhang, Jing

    2016-12-01

    In recent years, ecological degradation caused by irrational groundwater exploitation has been of growing concern in arid and semiarid regions. To address the groundwater-ecological issues, this paper proposes a groundwater-resource exploitation mode to evaluate the tradeoff between groundwater development and ecological environment in the northern Tianshan Mountains, northwest China's Xinjiang Uygur Autonomous Region. Field surveys and remote sensing studies were conducted to analyze the relation between the distribution of hydrological conditions and the occurrence of ecological types. The results show that there is a good correlation between groundwater depth and the supergene ecological type. Numerical simulations and ecological assessment models were applied to develop an ecology-oriented exploitation mode of groundwater resources. The mode allows the groundwater levels in different zones to be regulated by optimizing groundwater exploitation modes. The prediction results show that the supergene ecological quality will be better in 2020 and even more groundwater can be exploited in this mode. This study provides guidance for regional groundwater management, especially in regions with an obvious water scarcity.

  17. An ecology-oriented exploitation mode of groundwater resources in the northern foot of Tianshan Mountain, China

    DOE PAGES

    Shang, Haimin; Wang, Wenke; Dai, Zhenxue; ...

    2016-10-10

    In recent years, ecological degradation caused by irrational groundwater exploitation has been of growing concern in arid and semiarid regions. To address the groundwater-ecological issues, this paper proposes a groundwater-resource exploitation mode to evaluate the tradeoff between groundwater development and ecological environment in the northern Tianshan Mountains, northwest China’s Xinjiang Uygur Autonomous Region. Field surveys and remote sensing studies were conducted to analyze the relation between the distribution of hydrological conditions and the occurrence of ecological types. The results show that there is a good correlation between groundwater depth and the supergene ecological type. Numerical simulations and ecological assessment modelsmore » were applied to develop an ecology-oriented exploitation mode of groundwater resources. The mode allows the groundwater levels in different zones to be regulated by optimizing groundwater exploitation modes. The prediction results show that the supergene ecological quality will be better in 2020 and even more groundwater can be exploited in this mode. This study provides guidance for regional groundwater management, especially in regions with an obvious water scarcity.« less

  18. An ecology-oriented exploitation mode of groundwater resources in the northern foot of Tianshan Mountain, China

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

    Shang, Haimin; Wang, Wenke; Dai, Zhenxue

    In recent years, ecological degradation caused by irrational groundwater exploitation has been of growing concern in arid and semiarid regions. To address the groundwater-ecological issues, this paper proposes a groundwater-resource exploitation mode to evaluate the tradeoff between groundwater development and ecological environment in the northern Tianshan Mountains, northwest China’s Xinjiang Uygur Autonomous Region. Field surveys and remote sensing studies were conducted to analyze the relation between the distribution of hydrological conditions and the occurrence of ecological types. The results show that there is a good correlation between groundwater depth and the supergene ecological type. Numerical simulations and ecological assessment modelsmore » were applied to develop an ecology-oriented exploitation mode of groundwater resources. The mode allows the groundwater levels in different zones to be regulated by optimizing groundwater exploitation modes. The prediction results show that the supergene ecological quality will be better in 2020 and even more groundwater can be exploited in this mode. This study provides guidance for regional groundwater management, especially in regions with an obvious water scarcity.« less

  19. Leader-based and self-organized communication: modelling group-mass recruitment in ants.

    PubMed

    Collignon, Bertrand; Deneubourg, Jean Louis; Detrain, Claire

    2012-11-21

    For collective decisions to be made, the information acquired by experienced individuals about resources' location has to be shared with naïve individuals through recruitment. Here, we investigate the properties of collective responses arising from a leader-based recruitment and a self-organized communication by chemical trails. We develop a generalized model based on biological data drawn from Tetramorium caespitum ant species of which collective foraging relies on the coupling of group leading and trail recruitment. We show that for leader-based recruitment, small groups of recruits have to be guided in a very efficient way to allow a collective exploitation of food while large group requires less attention from their leader. In the case of self-organized recruitment through a chemical trail, a critical value of trail amount has to be laid per forager in order to launch collective food exploitation. Thereafter, ants can maintain collective foraging by emitting signal intensity below this threshold. Finally, we demonstrate how the coupling of both recruitment mechanisms may benefit to collectively foraging species. These theoretical results are then compared with experimental data from recruitment by T. caespitum ant colonies performing group-mass recruitment towards a single food source. We evidence the key role of leaders as initiators and catalysts of recruitment before this leader-based process is overtaken by self-organised communication through trails. This model brings new insights as well as a theoretical background to empirical studies about cooperative foraging in group-living species. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Cloud Based Earth Observation Data Exploitation Platforms

    NASA Astrophysics Data System (ADS)

    Romeo, A.; Pinto, S.; Loekken, S.; Marin, A.

    2017-12-01

    In the last few years data produced daily by several private and public Earth Observation (EO) satellites reached the order of tens of Terabytes, representing for scientists and commercial application developers both a big opportunity for their exploitation and a challenge for their management. New IT technologies, such as Big Data and cloud computing, enable the creation of web-accessible data exploitation platforms, which offer to scientists and application developers the means to access and use EO data in a quick and cost effective way. RHEA Group is particularly active in this sector, supporting the European Space Agency (ESA) in the Exploitation Platforms (EP) initiative, developing technology to build multi cloud platforms for the processing and analysis of Earth Observation data, and collaborating with larger European initiatives such as the European Plate Observing System (EPOS) and the European Open Science Cloud (EOSC). An EP is a virtual workspace, providing a user community with access to (i) large volume of data, (ii) algorithm development and integration environment, (iii) processing software and services (e.g. toolboxes, visualization routines), (iv) computing resources, (v) collaboration tools (e.g. forums, wiki, etc.). When an EP is dedicated to a specific Theme, it becomes a Thematic Exploitation Platform (TEP). Currently, ESA has seven TEPs in a pre-operational phase dedicated to geo-hazards monitoring and prevention, costal zones, forestry areas, hydrology, polar regions, urban areas and food security. On the technology development side, solutions like the multi cloud EO data processing platform provides the technology to integrate ICT resources and EO data from different vendors in a single platform. In particular it offers (i) Multi-cloud data discovery, (ii) Multi-cloud data management and access and (iii) Multi-cloud application deployment. This platform has been demonstrated with the EGI Federated Cloud, Innovation Platform Testbed Poland and the Amazon Web Services cloud. This work will present an overview of the TEPs and the multi-cloud EO data processing platform, and discuss their main achievements and their impacts in the context of distributed Research Infrastructures such as EPOS and EOSC.

  1. Multistep food plant processing at Grotta Paglicci (Southern Italy) around 32,600 cal B.P.

    PubMed Central

    Mariotti Lippi, Marta; Foggi, Bruno; Aranguren, Biancamaria; Ronchitelli, Annamaria; Revedin, Anna

    2015-01-01

    Residue analyses on a grinding tool recovered at Grotta Paglicci sublayer 23A [32,614 ± 429 calibrated (cal) B.P.], Southern Italy, have demonstrated that early modern humans collected and processed various plants. The recording of starch grains attributable to Avena (oat) caryopses expands our information about the food plants used for producing flour in Europe during the Paleolithic and about the origins of a food tradition persisting up to the present in the Mediterranean basin. The quantitative distribution of the starch grains on the surface of the grinding stone furnished information about the tool handling, confirming its use as a pestle-grinder, as suggested by the wear-trace analysis. The particular state of preservation of the starch grains suggests the use of a thermal treatment before grinding, possibly to accelerate drying of the plants, making the following process easier and faster. The study clearly indicates that the exploitation of plant resources was very important for hunter–gatherer populations, to the point that the Early Gravettian inhabitants of Paglicci were able to process food plants and already possessed a wealth of knowledge that was to become widespread after the dawn of agriculture. PMID:26351674

  2. Multistep food plant processing at Grotta Paglicci (Southern Italy) around 32,600 cal B.P.

    PubMed

    Mariotti Lippi, Marta; Foggi, Bruno; Aranguren, Biancamaria; Ronchitelli, Annamaria; Revedin, Anna

    2015-09-29

    Residue analyses on a grinding tool recovered at Grotta Paglicci sublayer 23A [32,614 ± 429 calibrated (cal) B.P.], Southern Italy, have demonstrated that early modern humans collected and processed various plants. The recording of starch grains attributable to Avena (oat) caryopses expands our information about the food plants used for producing flour in Europe during the Paleolithic and about the origins of a food tradition persisting up to the present in the Mediterranean basin. The quantitative distribution of the starch grains on the surface of the grinding stone furnished information about the tool handling, confirming its use as a pestle-grinder, as suggested by the wear-trace analysis. The particular state of preservation of the starch grains suggests the use of a thermal treatment before grinding, possibly to accelerate drying of the plants, making the following process easier and faster. The study clearly indicates that the exploitation of plant resources was very important for hunter-gatherer populations, to the point that the Early Gravettian inhabitants of Paglicci were able to process food plants and already possessed a wealth of knowledge that was to become widespread after the dawn of agriculture.

  3. Algal Proteins: Extraction, Application, and Challenges Concerning Production

    PubMed Central

    Bleakley, Stephen; Hayes, Maria

    2017-01-01

    Population growth combined with increasingly limited resources of arable land and fresh water has resulted in a need for alternative protein sources. Macroalgae (seaweed) and microalgae are examples of under-exploited “crops”. Algae do not compete with traditional food crops for space and resources. This review details the characteristics of commonly consumed algae, as well as their potential for use as a protein source based on their protein quality, amino acid composition, and digestibility. Protein extraction methods applied to algae to date, including enzymatic hydrolysis, physical processes, and chemical extraction and novel methods such as ultrasound-assisted extraction, pulsed electric field, and microwave-assisted extraction are discussed. Moreover, existing protein enrichment methods used in the dairy industry and the potential of these methods to generate high value ingredients from algae, such as bioactive peptides and functional ingredients are discussed. Applications of algae in human nutrition, animal feed, and aquaculture are examined. PMID:28445408

  4. Balancing the Budget through Social Exploitation: Why Hard Times Are Even Harder for Some

    PubMed Central

    Tropman, John; Nicklett, Emily

    2013-01-01

    In all societies needs and wants regularly exceed resources. Thus societies are always in deficit; demand always exceeds supply and “balancing the budget” is a constant social problem. To make matters somewhat worse, research suggests that need- and want-fulfillment tends to further stimulate the cycle of wantseeking rather than satiating desire. Societies use various resource-allocation mechanisms, including price, to cope with gaps between wants and resources. Social exploitation is a second mechanism, securing labor from population segments that can be coerced or convinced to perform necessary work for free or at below-market compensation. Using practical examples, this article develops a theoretical framework for understanding social exploitation. It then offers case examples of how different segments of the population emerge as exploited groups in the United States, due to changes in social policies. These exploitative processes have been exacerbated and accelerated by the economic downturn that began in 2007. PMID:23936753

  5. Exchange of natural enemies for biological control: is it a rocky road?-the road in the Euro-Mediterranean region and the South American common market.

    PubMed

    Coutinot, D; Briano, J; Parra, J R P; de Sá, L A N; Cônsoli, F L

    2013-02-01

    The access and benefit sharing (ABS) regulations from the Convention on Biological Diversity (CBD) for the use of natural resources became an important issue because the biodiversity of developing countries was heavily accessed and unilaterally exploited by pharmaceutical and seed companies. However, natural enemies used for biological control are living and unmodified genetic resources which cannot be patented and have been treated as resources such as drugs, seeds, or other commercial products. Consequently, the ABS requirements have limited not only the use of natural enemies but also the positive effects that scientifically supported biological control strategies have on the society, the environment, and the economy, reducing problems of pesticide residues, water and soil contamination, and non-target effects. During the last several years, the biological control scientific community has faced new and extremely complicated legislation dictated by a high and diverse number of governmental agencies at different levels, making the access to natural resources for biocontrol purposes a rocky road. Society at large should be aware of how the strict ABS regulations affect the use of natural enemies as biological resources to secure food production, food safety, and global environmental protection. We discuss in here the current difficulties derived from CBD for the exchange of natural enemies taking as example the Euro-Mediterranean region, Argentina, and Brazil to demonstrate how long and diverse are the steps to be followed to obtain the required permits for access and exportation/importation of natural enemies. We then argue that the public visibility of biocontrol strategies should be increased and their benefits highlighted in order to persuade legislators for the development of a less bureaucratic, more expedient, and more centralized regulatory frame, greatly favoring the practice and benefits of biological control. We finally propose a general framework in which ABS issues should be dealt in ways to attend the CBD, but also to make the use of natural resources for the biological control of pests to secure food production and security a possible alternative.

  6. How ecology shapes exploitation: a framework to predict the behavioural response of human and animal foragers along exploration-exploitation trade-offs.

    PubMed

    Monk, Christopher T; Barbier, Matthieu; Romanczuk, Pawel; Watson, James R; Alós, Josep; Nakayama, Shinnosuke; Rubenstein, Daniel I; Levin, Simon A; Arlinghaus, Robert

    2018-06-01

    Understanding how humans and other animals behave in response to changes in their environments is vital for predicting population dynamics and the trajectory of coupled social-ecological systems. Here, we present a novel framework for identifying emergent social behaviours in foragers (including humans engaged in fishing or hunting) in predator-prey contexts based on the exploration difficulty and exploitation potential of a renewable natural resource. A qualitative framework is introduced that predicts when foragers should behave territorially, search collectively, act independently or switch among these states. To validate it, we derived quantitative predictions from two models of different structure: a generic mathematical model, and a lattice-based evolutionary model emphasising exploitation and exclusion costs. These models independently identified that the exploration difficulty and exploitation potential of the natural resource controls the social behaviour of resource exploiters. Our theoretical predictions were finally compared to a diverse set of empirical cases focusing on fisheries and aquatic organisms across a range of taxa, substantiating the framework's predictions. Understanding social behaviour for given social-ecological characteristics has important implications, particularly for the design of governance structures and regulations to move exploited systems, such as fisheries, towards sustainability. Our framework provides concrete steps in this direction. © 2018 John Wiley & Sons Ltd/CNRS.

  7. Food Web Topology in High Mountain Lakes

    PubMed Central

    Sánchez-Hernández, Javier; Cobo, Fernando; Amundsen, Per-Arne

    2015-01-01

    Although diversity and limnology of alpine lake systems are well studied, their food web structure and properties have rarely been addressed. Here, the topological food webs of three high mountain lakes in Central Spain were examined. We first addressed the pelagic networks of the lakes, and then we explored how food web topology changed when benthic biota was included to establish complete trophic networks. We conducted a literature search to compare our alpine lacustrine food webs and their structural metrics with those of 18 published lentic webs using a meta-analytic approach. The comparison revealed that the food webs in alpine lakes are relatively simple, in terms of structural network properties (linkage density and connectance), in comparison with lowland lakes, but no great differences were found among pelagic networks. The studied high mountain food webs were dominated by a high proportion of omnivores and species at intermediate trophic levels. Omnivores can exploit resources at multiple trophic levels, and this characteristic might reduce competition among interacting species. Accordingly, the trophic overlap, measured as trophic similarity, was very low in all three systems. Thus, these alpine networks are characterized by many omnivorous consumers with numerous prey species and few consumers with a single or few prey and with low competitive interactions among species. The present study emphasizes the ecological significance of omnivores in high mountain lakes as promoters of network stability and as central players in energy flow pathways via food partitioning and enabling energy mobility among trophic levels. PMID:26571235

  8. Food Web Topology in High Mountain Lakes.

    PubMed

    Sánchez-Hernández, Javier; Cobo, Fernando; Amundsen, Per-Arne

    2015-01-01

    Although diversity and limnology of alpine lake systems are well studied, their food web structure and properties have rarely been addressed. Here, the topological food webs of three high mountain lakes in Central Spain were examined. We first addressed the pelagic networks of the lakes, and then we explored how food web topology changed when benthic biota was included to establish complete trophic networks. We conducted a literature search to compare our alpine lacustrine food webs and their structural metrics with those of 18 published lentic webs using a meta-analytic approach. The comparison revealed that the food webs in alpine lakes are relatively simple, in terms of structural network properties (linkage density and connectance), in comparison with lowland lakes, but no great differences were found among pelagic networks. The studied high mountain food webs were dominated by a high proportion of omnivores and species at intermediate trophic levels. Omnivores can exploit resources at multiple trophic levels, and this characteristic might reduce competition among interacting species. Accordingly, the trophic overlap, measured as trophic similarity, was very low in all three systems. Thus, these alpine networks are characterized by many omnivorous consumers with numerous prey species and few consumers with a single or few prey and with low competitive interactions among species. The present study emphasizes the ecological significance of omnivores in high mountain lakes as promoters of network stability and as central players in energy flow pathways via food partitioning and enabling energy mobility among trophic levels.

  9. Optimizing Search and Ranking in Folksonomy Systems by Exploiting Context Information

    NASA Astrophysics Data System (ADS)

    Abel, Fabian; Henze, Nicola; Krause, Daniel

    Tagging systems enable users to annotate resources with freely chosen keywords. The evolving bunch of tag assignments is called folksonomy and there exist already some approaches that exploit folksonomies to improve resource retrieval. In this paper, we analyze and compare graph-based ranking algorithms: FolkRank and SocialPageRank. We enhance these algorithms by exploiting the context of tags, and evaluate the results on the GroupMe! dataset. In GroupMe!, users can organize and maintain arbitrary Web resources in self-defined groups. When users annotate resources in GroupMe!, this can be interpreted in context of a certain group. The grouping activity itself is easy for users to perform. However, it delivers valuable semantic information about resources and their context. We present GRank that uses the context information to improve and optimize the detection of relevant search results, and compare different strategies for ranking result lists in folksonomy systems.

  10. Impacts of irrigation on groundwater depletion in the North China Plain

    NASA Astrophysics Data System (ADS)

    Ge, Yuqi; Lei, Huimin

    2017-04-01

    Groundwater resources is an essential water supply for agriculture in the North China Plain (NCP) which is one of the most important food production areas in China. In the past decades, excessive groundwater-fed irrigation in this area has caused sharp decline in groundwater table. However, accurate monitoring on the net groundwater exploitation is still difficult, mainly due to a lack of complete groundwater exploitation monitoring network. This hinders an accurate evaluation of the effects of agricultural managements on shallow groundwater table. In this study, we use an existing method to estimate the net irrigation amount at the county level, and evaluate the effects of current agricultural management on groundwater depletion. We apply this method in five typical counties in the NCP to estimate annual net irrigation amount from 2002 to 2015, based on meteorological data (2002-2015) and remote sensing ET data (2002-2015) . First, an agro-hydrological model (Soil-Water-Atmosphere-Plant, SWAP) is calibrated and validated at field scale based on the measured data from flux towers. Second, the model is established at reginal scale by spatial discretization. Third, we use an optimization tool (Parameter ESTimation, PEST) to optimize the irrigation parameter in SWAP so as the simulated evapotranspiration (ET) by SWAP is closest to the remote sensing ET. We expect that the simulated irrigation amount from the optimized parameter is the estimated net irrigation amount. Finally, the contribution of agricultural management to the observed groundwater depletion is assessed by calculating the groundwater balance which considers the estimated net irrigation amount, observed lateral groundwater, rainfall recharge, deep seepage, evaporation from phreatic water and domestic water use. The study is expected to give a scientific basis for alleviating the over-exploitation of groundwater resources in the area.

  11. The rebuilding imperative in fisheries: Clumsy solutions for a wicked problem?

    NASA Astrophysics Data System (ADS)

    Khan, Ahmed S.; Neis, Barb

    2010-10-01

    There is mounting evidence that global fisheries are in crisis and about 25-30% of fish stocks are over exploited, depleted or recovering. Fish landings are increasingly coming from fully-exploited and over-exploited fisheries, and from intensive aquaculture that often relies indirectly on reduction fisheries. This poses severe challenges for marine ecosystems as well as food security and the livelihoods of resource-dependent coastal communities. Growing awareness of these social, economic and ecological consequences of overfishing is reflected in an expanding literature which shows that reducing fishing effort to allow fish stocks to recover has been the main focus of management efforts, but successful examples of stock recovery are few. An alternative, less explored social-ecological approach focuses on rebuilding entire ‘fish chains’ from oceans to plate. This paper supports this alternative approach. A review and synthesis of stock rebuilding initiatives worldwide suggests effective governance is central to rebuilding, and fisheries governance is a wicked problem. Wicked problems are complex, persistent or reoccurring and hard to fix because they are linked to broader social, economic and policy issues. This review and analysis implies that, due to socioeconomic and sociopolitical concerns, fisheries governance challenges are particularly wicked when dealing with collapsed fisheries and rebuilding efforts. The paper concludes that rebuilding might benefit from experimenting with clumsy solutions. Clumsy solutions are exploratory, include inputs from a broad range of stakeholders along the fish chain, and require information sharing, knowledge synthesis, and trust building. Moreover, clumsy solutions that address power relations, collective action dilemmas, and the fundamental question of ‘rebuilding for whom’ are essential for stewardship, equity and long-term resource sustainability.

  12. Composite collective decision-making.

    PubMed

    Czaczkes, Tomer J; Czaczkes, Benjamin; Iglhaut, Carolin; Heinze, Jürgen

    2015-06-22

    Individual animals are adept at making decisions and have cognitive abilities, such as memory, which allow them to hone their decisions. Social animals can also share information. This allows social animals to make adaptive group-level decisions. Both individual and collective decision-making systems also have drawbacks and limitations, and while both are well studied, the interaction between them is still poorly understood. Here, we study how individual and collective decision-making interact during ant foraging. We first gathered empirical data on memory-based foraging persistence in the ant Lasius niger. We used these data to create an agent-based model where ants may use social information (trail pheromones), private information (memories) or both to make foraging decisions. The combined use of social and private information by individuals results in greater efficiency at the group level than when either information source was used alone. The modelled ants couple consensus decision-making, allowing them to quickly exploit high-quality food sources, and combined decision-making, allowing different individuals to specialize in exploiting different resource patches. Such a composite collective decision-making system reaps the benefits of both its constituent parts. Exploiting such insights into composite collective decision-making may lead to improved decision-making algorithms. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  13. Pottery use by early Holocene hunter-gatherers of the Korean peninsula closely linked with the exploitation of marine resources

    NASA Astrophysics Data System (ADS)

    Shoda, Shinya; Lucquin, Alexandre; Ahn, Jae-ho; Hwang, Chul-joo; Craig, Oliver E.

    2017-08-01

    The earliest pottery on the Korean peninsula dates to the early Holocene, notably later than other regions of East Asia, such as Japan, the Russian Far East and Southern China. To shed light on the function of such early Korean pottery and to understand the motivations for its adoption, organic residue analysis was conducted on pottery sherds and adhered surface deposit on the wall of pottery vessels (foodcrusts) excavated from the Sejuk shell midden (7.7-6.8ka calBP) on the southeastern coast and the Jukbyeon-ri site (7.9-6.9ka calBP) on the eastern coast of the Korean peninsula, that represents the earliest pottery assemblages with reliable radiocarbon dates. Through chemical and isotopic residue analysis, we conclude that the use of pottery at these sites was oriented towards marine resources, supported by lipid biomarkers typical of aquatic organisms and stable carbon isotope values that matched authentic marine reference fats. The findings contrast with other archaeological evidence, which shows that a wider range of available food resources were exploited. Therefore, we conclude pottery was used selectively for processing aquatic organisms perhaps including the rendering of aquatic oils for storage. Early pottery use in Korea is broadly similar to other prehistoric temperate hunter-gatherers, such as in Japan, northern Europe and northern America. However, it is also notable that elaborately decorated red burnished pottery excavated from isolated location at the Jukbyeon-ri site had a different usage pattern, which indicates that division of pottery use by vessel form was established even at this early stage.

  14. Ant-mediated ecosystem processes are driven by trophic community structure but mainly by the environment.

    PubMed

    Salas-Lopez, Alex; Mickal, Houadria; Menzel, Florian; Orivel, Jérôme

    2017-01-01

    The diversity and functional identity of organisms are known to be relevant to the maintenance of ecosystem processes but can be variable in different environments. Particularly, it is uncertain whether ecosystem processes are driven by complementary effects or by dominant groups of species. We investigated how community structure (i.e., the diversity and relative abundance of biological entities) explains the community-level contribution of Neotropical ant communities to different ecosystem processes in different environments. Ants were attracted with food resources representing six ant-mediated ecosystem processes in four environments: ground and vegetation strata in cropland and forest habitats. The exploitation frequencies of the baits were used to calculate the taxonomic and trophic structures of ant communities and their contribution to ecosystem processes considered individually or in combination (i.e., multifunctionality). We then investigated whether community structure variables could predict ecosystem processes and whether such relationships were affected by the environment. We found that forests presented a greater biodiversity and trophic complementarity and lower dominance than croplands, but this did not affect ecosystem processes. In contrast, trophic complementarity was greater on the ground than on vegetation and was followed by greater resource exploitation levels. Although ant participation in ecosystem processes can be predicted by means of trophic-based indices, we found that variations in community structure and performance in ecosystem processes were best explained by environment. We conclude that determining the extent to which the dominance and complementarity of communities affect ecosystem processes in different environments requires a better understanding of resource availability to different species.

  15. On international fisheries agreements, entry deterrence, and ecological uncertainty.

    PubMed

    Ellefsen, Hans; Grønbæk, Lone; Ravn-Jonsen, Lars

    2017-05-15

    A prerequisite for an international fisheries agreement (IFA) to be stable is that parties expect the benefits from joining the agreement to exceed the benefits from free riding on the agreement, and parties only comply with the agreement as long as this is true. The agreement, therefore, implicitly builds on an expectation of the ecological condition of the natural resource. Game theoretical models often assume that all parties have the same (often perfect) information about the resource and that the exploitation is an equilibrium use of the stock. As stated by experts in natural science, the fish ecology still has many open questions, for example how to predict population dynamics, migration patterns, food availability, etc. In some cases, parties disagree about the state, abundance, and migration of a stock, which can reduce the possibilities of reaching an agreement for exploitation of the stock. This paper develops a model and applies it to the North-East Atlantic mackerel fishery, in order to analyze an IFA under different ecological scenarios, and also combines the model with the economic theory of entry deterrence. The model is used empirically to determine whether the parties with original access to the resource have an advantage when forming an agreement with a new party in having the ability to fish the stock down to a smaller size and thereby prevent another party from entering into the fishery. With a basis in entry deterrence, combined with lack of information, the paper illustrates the obstacles that have made an agreement for the North-East Atlantic mackerel so difficult to achieve. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Correlation of water with carbon/energy footprints for effective agricultural and livestock products classification

    NASA Astrophysics Data System (ADS)

    Borsato, Eros; Marinello, Francesco; Tarolli, Paolo

    2017-04-01

    World population is increasing and human diet is becoming of considerable concern for human welfare. Natural resources are overexploited and governments need policies for a good management of the environment. Sustainable agriculture can provide some solutions, as it minimizes inputs, wastes or pollution. The aim of the present study is to provide a combined analysis of different footprints approaches in order to allow comparison of different agricultural and livestock products in terms of efficiency of resource exploitation. Time is the real important variable that influences the footprint. Water use efficiency, greenhouse gas emissions and energy indexes are included in this study. The study takes advantage of indexes collected from a wide bibliography focused on different fresh agricultural products: the target is the definition of a time table of footprints for agricultural products. Starting from a top-down prospective, an analysis of the environmental footprint for different products is an approach to understand which products can be more sustainable for human diet. This study distinguishes different clusters in different sub-cluster of vegetable products and animal products. The classification is based on a comparison of water consumption in relation to yield, greenhouse gas emissions equivalent and energy for a given product quantity. Additionally time is considered, which affects sustainability, in terms of inputs caught for a period. The footprint is spread out in time, thus changing its relevance with respect to the exploitation of a resource. Ultimately, this works wants to propose a new original basis for sustainability metrics, allowing an effective quantitative comparison of food products for a more conscious human diet.

  17. Inter-Tributary Movements by Resident Salmonids across a Boreal Riverscape

    PubMed Central

    Bentley, Kale T.; Schindler, Daniel E.; Armstrong, Jonathan B.; Cline, Timothy J.; Brooks, Gabriel T.

    2015-01-01

    Stream-dwelling fishes inhabit river networks where resources are distributed heterogeneously across space and time. Current theory emphasizes that fishes often perform large-scale movements among habitat patches for reproduction and seeking refugia, but assumes that fish are relatively sedentary during growth phases of their life cycle. Using stationary passive integrated transponder (PIT)-tag antennas and snorkel surveys, we assessed the individual and population level movement patterns of two species of fish across a network of tributaries within the Wood River basin in southwestern Alaska where summer foraging opportunities vary substantially among streams, seasons, and years. Across two years, Arctic grayling (Thymallus arcticus) and rainbow trout (Oncorhynchus mykiss) exhibited kilometer-scale movements among streams during the summer growing season. Although we monitored movements at a small fraction of all tributaries used by grayling and rainbow trout, approximately 50% of individuals moved among two or more streams separated by at least 7 km within a single summer. Movements were concentrated in June and July, and subsided by early August. The decline in movements coincided with spawning by anadromous sockeye salmon, which offer a high-quality resource pulse of food to resident species. Inter-stream movements may represent prospecting behavior as individuals seek out the most profitable foraging opportunities that are patchily distributed across space and time. Our results highlight that large-scale movements may not only be necessary for individuals to fulfill their life-cycle, but also to exploit heterogeneously spaced trophic resources. Therefore, habitat fragmentation and homogenization may have strong, but currently undescribed, ecological effects on the access to critical food resources in stream-dwelling fish populations. PMID:26379237

  18. Long-term impacts of invasive species on a native top predator in a large lake system

    USGS Publications Warehouse

    Rush, Scott A.; Paterson, Gordon; Johnson, Tim B.; Drouillard, Ken G.; Haffner, Gordon D.; Hebert, Craig E.; Arts, Michael T.; McGoldrick, Daryl J.; Backus, Sean M.; Lantry, Brian F.; Lantry, Jana R.; Schaner, Ted; Fisk, Aaron T.

    2012-01-01

    1. Declining abundances of forage fish and the introduction and establishment of non-indigenous species have the potential to substantially alter resource and habitat exploitation by top predators in large lakes. 2. We measured stable isotopes of carbon (δ13C) and nitrogen (δ15N) in field-collected and archived samples of Lake Ontario lake trout (Salvelinus namaycush) and five species of prey fish and compared current trophic relationships of this top predator with historical samples. 3. Relationships between δ15N and lake trout age were temporally consistent throughout Lake Ontario and confirmed the role of lake trout as a top predator in this food web. However, δ13C values for age classes of lake trout collected in 2008 ranged from 1.0 to 3.9‰ higher than those reported for the population sampled in 1992. 4. Isotope mixing models predicted that these changes in resource assimilation were owing to the replacement of rainbow smelt (Osmerus mordax) by round goby (Neogobius melanostomus) in lake trout diet and increased reliance on carbon resources derived from nearshore production. This contrasts with the historical situation in Lake Ontario where δ13C values of the lake trout population were dominated by a reliance on offshore carbon production. 5. These results indicate a reduced capacity of the Lake Ontario offshore food web to support the energetic requirements of lake trout and that this top predator has become increasingly reliant on prey resources that are derived from nearshore carbon pathways.

  19. Assessing and Exploiting Functional Diversity in Germplasm Pools to Enhance Abiotic Stress Adaptation and Yield in Cereals and Food Legumes

    PubMed Central

    Dwivedi, Sangam L.; Scheben, Armin; Edwards, David; Spillane, Charles; Ortiz, Rodomiro

    2017-01-01

    There is a need to accelerate crop improvement by introducing alleles conferring host plant resistance, abiotic stress adaptation, and high yield potential. Elite cultivars, landraces and wild relatives harbor useful genetic variation that needs to be more easily utilized in plant breeding. We review genome-wide approaches for assessing and identifying alleles associated with desirable agronomic traits in diverse germplasm pools of cereals and legumes. Major quantitative trait loci and single nucleotide polymorphisms (SNPs) associated with desirable agronomic traits have been deployed to enhance crop productivity and resilience. These include alleles associated with variation conferring enhanced photoperiod and flowering traits. Genetic variants in the florigen pathway can provide both environmental flexibility and improved yields. SNPs associated with length of growing season and tolerance to abiotic stresses (precipitation, high temperature) are valuable resources for accelerating breeding for drought-prone environments. Both genomic selection and genome editing can also harness allelic diversity and increase productivity by improving multiple traits, including phenology, plant architecture, yield potential and adaptation to abiotic stresses. Discovering rare alleles and useful haplotypes also provides opportunities to enhance abiotic stress adaptation, while epigenetic variation has potential to enhance abiotic stress adaptation and productivity in crops. By reviewing current knowledge on specific traits and their genetic basis, we highlight recent developments in the understanding of crop functional diversity and identify potential candidate genes for future use. The storage and integration of genetic, genomic and phenotypic information will play an important role in ensuring broad and rapid application of novel genetic discoveries by the plant breeding community. Exploiting alleles for yield-related traits would allow improvement of selection efficiency and overall genetic gain of multigenic traits. An integrated approach involving multiple stakeholders specializing in management and utilization of genetic resources, crop breeding, molecular biology and genomics, agronomy, stress tolerance, and reproductive/seed biology will help to address the global challenge of ensuring food security in the face of growing resource demands and climate change induced stresses. PMID:28900432

  20. Assessing and Exploiting Functional Diversity in Germplasm Pools to Enhance Abiotic Stress Adaptation and Yield in Cereals and Food Legumes.

    PubMed

    Dwivedi, Sangam L; Scheben, Armin; Edwards, David; Spillane, Charles; Ortiz, Rodomiro

    2017-01-01

    There is a need to accelerate crop improvement by introducing alleles conferring host plant resistance, abiotic stress adaptation, and high yield potential. Elite cultivars, landraces and wild relatives harbor useful genetic variation that needs to be more easily utilized in plant breeding. We review genome-wide approaches for assessing and identifying alleles associated with desirable agronomic traits in diverse germplasm pools of cereals and legumes. Major quantitative trait loci and single nucleotide polymorphisms (SNPs) associated with desirable agronomic traits have been deployed to enhance crop productivity and resilience. These include alleles associated with variation conferring enhanced photoperiod and flowering traits. Genetic variants in the florigen pathway can provide both environmental flexibility and improved yields. SNPs associated with length of growing season and tolerance to abiotic stresses (precipitation, high temperature) are valuable resources for accelerating breeding for drought-prone environments. Both genomic selection and genome editing can also harness allelic diversity and increase productivity by improving multiple traits, including phenology, plant architecture, yield potential and adaptation to abiotic stresses. Discovering rare alleles and useful haplotypes also provides opportunities to enhance abiotic stress adaptation, while epigenetic variation has potential to enhance abiotic stress adaptation and productivity in crops. By reviewing current knowledge on specific traits and their genetic basis, we highlight recent developments in the understanding of crop functional diversity and identify potential candidate genes for future use. The storage and integration of genetic, genomic and phenotypic information will play an important role in ensuring broad and rapid application of novel genetic discoveries by the plant breeding community. Exploiting alleles for yield-related traits would allow improvement of selection efficiency and overall genetic gain of multigenic traits. An integrated approach involving multiple stakeholders specializing in management and utilization of genetic resources, crop breeding, molecular biology and genomics, agronomy, stress tolerance, and reproductive/seed biology will help to address the global challenge of ensuring food security in the face of growing resource demands and climate change induced stresses.

  1. Food selectivity and processing by the cold-water coral Lophelia pertusa

    NASA Astrophysics Data System (ADS)

    van Oevelen, Dick; Mueller, Christina E.; Lundälv, Tomas; Middelburg, Jack J.

    2016-10-01

    Cold-water corals form prominent reef ecosystems along ocean margins that depend on suspended resources produced in surface waters. In this study, we investigated food processing of 13C and 15N labelled bacteria and algae by the cold-water coral Lophelia pertusa. Coral respiration, tissue incorporation of C and N and metabolically derived C incorporation into the skeleton were traced following the additions of different food concentrations (100, 300, 1300 µg C L-1) and two ratios of suspended bacterial and algal biomass (1 : 1, 3 : 1). Respiration and tissue incorporation by L. pertusa increased markedly following exposure to higher food concentrations. The net growth efficiency of L. pertusa was low (0.08 ± 0.03), which is consistent with its slow growth rate. The contribution of algae and bacteria to total coral assimilation was proportional to the food mixture in the two lowest food concentrations, but algae were preferred over bacteria as a food source at the highest food concentration. Similarly, the stoichiometric uptake of C and N was coupled in the low and medium food treatment, but was uncoupled in the high food treatment and indicated a comparatively higher uptake or retention of bacterial carbon as compared to algal nitrogen. We argue that behavioural responses for these small-sized food particles, such as tentacle behaviour, mucus trapping and physiological processing, are more likely to explain the observed food selectivity as compared to physical-mechanical considerations. A comparison of the experimental food conditions to natural organic carbon concentrations above CWC reefs suggests that L. pertusa is well adapted to exploit temporal pulses of high organic matter concentrations in the bottom water caused by internal waves and downwelling events.

  2. New advances in the integrated management of food processing by-products in Europe: sustainable exploitation of fruit and cereal processing by-products with the production of new food products (NAMASTE EU).

    PubMed

    Fava, Fabio; Zanaroli, Giulio; Vannini, Lucia; Guerzoni, Elisabetta; Bordoni, Alessandra; Viaggi, Davide; Robertson, Jim; Waldron, Keith; Bald, Carlos; Esturo, Aintzane; Talens, Clara; Tueros, Itziar; Cebrián, Marta; Sebők, András; Kuti, Tunde; Broeze, Jan; Macias, Marta; Brendle, Hans-Georg

    2013-09-25

    By-products generated every year by the European fruit and cereal processing industry currently exceed several million tons. They are disposed of mainly through landfills and thus are largely unexploited sources of several valuable biobased compounds potentially profitable in the formulation of novel food products. The opportunity to design novel strategies to turn them into added value products and food ingredients via novel and sustainable processes is the main target of recently EC-funded FP7 project NAMASTE-EU. NAMASTE-EU aims at developing new laboratory-scale protocols and processes for the exploitation of citrus processing by-products and wheat bran surpluses via the production of ingredients useful for the formulation of new beverage and food products. Among the main results achieved in the first two years of the project, there are the development and assessment of procedures for the selection, stabilization and the physical/biological treatment of citrus and wheat processing by-products, the obtainment and recovery of some bioactive molecules and ingredients and the development of procedures for assessing the quality of the obtained ingredients and for their exploitation in the preparation of new food products. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. National Policies and strategies on science and technology for development.

    PubMed

    Ayob, A

    1979-01-01

    Malaysia's economy continues to be dependent upon the primary producing sectors, based on the exploitation or use of her natural resources. At this Malaysia is the world's largest exporter of natural rubber, tin, tropical hardwoods and palm oil. There is still wide scope for developing new application of science and technology in the rubber industry, and the scope remains even wider in other agricultural sectors. In order to accelerate development in the traditional agricultural sector, that is, those related to food production, the Malaysian Agricultural Research and Development Institute (MARDI) was established in 1970 to undertake research in the development of crops other than rubber. Progress has been relatively slow in the development of agriculture. In forestry much work needs to be done in the application of science and technology to forest management, logging, timber utilization, silviculture and the related field of forest regeneration, tree breeding, forest protection and soil conservation. Further development of the mining sector calls for the application of new technology both in prospecting for new sources of minerals and in exploitation. Development of off-shore technology will become increasingly important. Although a major sector in resources development is energy, there is, as yet, no energy policy. Structural diversification is recognized as a basic need for the economic development of Malaysia. Malaysia will have a great demand for trained scientific and technological personnel.

  4. Landscape movements by two species of migratory nectar-feeding bats (Leptonycteris) in a northern area of seasonal sympatry

    USGS Publications Warehouse

    Bogan, Michael A.; Cryan, Paul; Weise, Christa D.; Valdez, Ernest W.

    2017-01-01

    Animals often migrate to exploit seasonally ephemeral food. Three species of nectar-feeding phyllostomid bats migrate north from Mexico into deserts of the United States each spring and summer to feed on blooms of columnar cactus and century plants (Agave spp.). However, the habitat needs of these important desert pollinators are poorly understood. We followed the nighttime movements of 2 species of long-nosed bats (Leptonycteris yerbabuenae and L. nivalis) in an area of late-summer sympatry at the northern edges of their migratory ranges. We radio-tracked bats in extreme southwestern New Mexico during 22 nights over 2 summers and acquired location estimates for 31 individuals. Both species cohabitated 2 major day roosts that were 30 km apart and in different mountain ranges, and individual bats sometimes moved between the roosts. Sampling was opportunistic and limited, but there were no obvious qualitative differences in observed patterns of movement between species or years, or among sex, age, and reproductive groups. Both species were observed foraging most often in the mountain range that had a relatively higher observed density of presumed food plants (Agave palmeri); when roosting in an adjacent mountain range, bats sometimes commuted >20 km one way to forage. Contrary to evidence indicating these species partition resources farther south in Mexico, our findings suggest that L. yerbabuenae and L. nivalis seasonally share common roost and food resources during late summer in this northern area of sympatry.

  5. Use of social information in seabirds: compass rafts indicate the heading of food patches.

    PubMed

    Weimerskirch, Henri; Bertrand, Sophie; Silva, Jaime; Marques, Jose Carlos; Goya, Elisa

    2010-03-29

    Ward and Zahavi suggested in 1973 that colonies could serve as information centres, through a transfer of information on the location of food resources between unrelated individuals (Information Centre Hypothesis). Using GPS tracking and observations on group movements, we studied the search strategy and information transfer in two of the most colonial seabirds, Guanay cormorants (Phalacrocorax bougainvillii) and Peruvian boobies (Sula variegata). Both species breed together and feed on the same prey. They do return to the same feeding zone from one trip to the next indicating high unpredictability in the location of food resources. We found that the Guanay cormorants use social information to select their bearing when departing the colony. They form a raft at the sea surface whose position is continuously adjusted to the bearing of the largest returning columns of cormorants. As such, the raft serves as a compass signal that gives an indication on the location of the food patches. Conversely, Peruvian boobies rely mainly on personal information based on memory to take heading at departure. They search for food patches solitarily or in small groups through network foraging by detecting the white plumage of congeners visible at long distance. Our results show that information transfer does occur and we propose a new mechanism of information transfer based on the use of rafts off colonies. The use of rafts for information transfer may be common in central place foraging colonial seabirds that exploit short lasting and/or unpredictably distributed food patches. Over the past decades Guanay cormorants have declined ten times whereas Peruvian boobies have remained relatively stable. We suggest that the decline of the cormorants could be related to reduced social information opportunities and that social behaviour and search strategies have the potential to play an important role in the population dynamics of colonial animals.

  6. Use of Social Information in Seabirds: Compass Rafts Indicate the Heading of Food Patches

    PubMed Central

    Weimerskirch, Henri; Bertrand, Sophie; Silva, Jaime; Marques, Jose Carlos; Goya, Elisa

    2010-01-01

    Ward and Zahavi suggested in 1973 that colonies could serve as information centres, through a transfer of information on the location of food resources between unrelated individuals (Information Centre Hypothesis). Using GPS tracking and observations on group movements, we studied the search strategy and information transfer in two of the most colonial seabirds, Guanay cormorants (Phalacrocorax bougainvillii) and Peruvian boobies (Sula variegata). Both species breed together and feed on the same prey. They do return to the same feeding zone from one trip to the next indicating high unpredictability in the location of food resources. We found that the Guanay cormorants use social information to select their bearing when departing the colony. They form a raft at the sea surface whose position is continuously adjusted to the bearing of the largest returning columns of cormorants. As such, the raft serves as a compass signal that gives an indication on the location of the food patches. Conversely, Peruvian boobies rely mainly on personal information based on memory to take heading at departure. They search for food patches solitarily or in small groups through network foraging by detecting the white plumage of congeners visible at long distance. Our results show that information transfer does occur and we propose a new mechanism of information transfer based on the use of rafts off colonies. The use of rafts for information transfer may be common in central place foraging colonial seabirds that exploit short lasting and/or unpredictably distributed food patches. Over the past decades Guanay cormorants have declined ten times whereas Peruvian boobies have remained relatively stable. We suggest that the decline of the cormorants could be related to reduced social information opportunities and that social behaviour and search strategies have the potential to play an important role in the population dynamics of colonial animals. PMID:20360959

  7. Deep Eutectic Solvents pretreatment of agro-industrial food waste.

    PubMed

    Procentese, Alessandra; Raganati, Francesca; Olivieri, Giuseppe; Russo, Maria Elena; Rehmann, Lars; Marzocchella, Antonio

    2018-01-01

    Waste biomass from agro-food industries are a reliable and readily exploitable resource. From the circular economy point of view, direct residues from these industries exploited for production of fuel/chemicals is a winning issue, because it reduces the environmental/cost impact and improves the eco-sustainability of productions. The present paper reports recent results of deep eutectic solvent (DES) pretreatment on a selected group of the agro-industrial food wastes (AFWs) produced in Europe. In particular, apple residues, potato peels, coffee silverskin, and brewer's spent grains were pretreated with two DESs, (choline chloride-glycerol and choline chloride-ethylene glycol) for fermentable sugar production. Pretreated biomass was enzymatic digested by commercial enzymes to produce fermentable sugars. Operating conditions of the DES pretreatment were changed in wide intervals. The solid to solvent ratio ranged between 1:8 and 1:32, and the temperature between 60 and 150 °C. The DES reaction time was set at 3 h. Optimal operating conditions were: 3 h pretreatment with choline chloride-glycerol at 1:16 biomass to solvent ratio and 115 °C. Moreover, to assess the expected European amount of fermentable sugars from the investigated AFWs, a market analysis was carried out. The overall sugar production was about 217 kt yr -1 , whose main fraction was from the hydrolysis of BSGs pretreated with choline chloride-glycerol DES at the optimal conditions. The reported results boost deep investigation on lignocellulosic biomass using DES. This investigated new class of solvents is easy to prepare, biodegradable and cheaper than ionic liquid. Moreover, they reported good results in terms of sugars' release at mild operating conditions (time, temperature and pressure).

  8. Unravelling rootstock×scion interactions to improve food security.

    PubMed

    Albacete, Alfonso; Martínez-Andújar, Cristina; Martínez-Pérez, Ascensión; Thompson, Andrew J; Dodd, Ian C; Pérez-Alfocea, Francisco

    2015-04-01

    While much recent science has focused on understanding and exploiting root traits as new opportunities for crop improvement, the use of rootstocks has enhanced productivity of woody perennial crops for centuries. Grafting of vegetable crops has developed very quickly in the last 50 years, mainly to induce shoot vigour and to overcome soil-borne diseases in solanaceous and cucurbitaceous crops. In most cases, such progress has largely been due to empirical interactions between farmers, gardeners, and botanists, with limited insights into the underlying physiological mechanisms. Only during the last 20 years has science realized the potential of this old activity and studied the physiological and molecular mechanisms involved in rootstock×scion interactions, thereby not only explaining old phenomena but also developing new tools for crop improvement. Rootstocks can contribute to food security by: (i) increasing the yield potential of elite varieties; (ii) closing the yield gap under suboptimal growing conditions; (iii) decreasing the amount of chemical (pesticides and fertilizers) contaminants in the soil; (iv) increasing the efficiency of use of natural (water and soil) resources; (v) generating new useful genotypic variability (via epigenetics); and (vi) creating new products with improved quality. The potential of grafting is as broad as the genetic variability able to cross a potential incompatibility barrier between the rootstock and the scion. Therefore, understanding the mechanisms underlying the phenotypic variability resulting from rootstock×scion×environment interactions will certainly contribute to developing and exploiting rootstocks for food security. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology. All rights reserved. For permissions, please email: journals.permissions@oup.com.

  9. New parasitoid-predator associations: female parasitoids do not avoid competition with generalist predators when sharing invasive prey

    NASA Astrophysics Data System (ADS)

    Chailleux, Anaïs; Wajnberg, Eric; Zhou, Yuxiang; Amiens-Desneux, Edwige; Desneux, Nicolas

    2014-12-01

    Optimal habitat selection is essential for species survival in ecosystems, and interspecific competition is a key ecological mechanism for many observed species association patterns. Specialized animal species are commonly affected by resource and interference competition with generalist and/or omnivorous competitors, so avoidance behavior could be expected. We hypothesize that specialist species may exploit broad range cues from such potential resource competitors (i.e., cues possibly common to various generalist and/or omnivorous predators) to avoid costly competition regarding food or reproduction, even in new species associations. We tested this hypothesis by studying short-term interactions between a native larval parasitoid and a native generalist omnivorous predator recently sharing the same invasive host/prey, the leaf miner Tuta absoluta. We observed a strong negative effect of kleptoparasitism (food resource stealing) instead of classical intraguild predation on immature parasitoids. There was no evidence that parasitoid females avoided the omnivorous predator when searching for oviposition sites, although we studied both long- and short-range known detection mechanisms. Therefore, we conclude that broad range cue avoidance may not exist in our biological system, probably because it would lead to too much oviposition site avoidance which would not be an efficient and, thus, beneficial strategy. If confirmed in other parasitoids or specialist predators, our findings may have implications for population dynamics, especially in the current context of increasing invasive species and the resulting creation of many new species associations.

  10. Hunting and use of terrestrial fauna used by Caiçaras from the Atlantic Forest coast (Brazil)

    PubMed Central

    2009-01-01

    Background The Brazilian Atlantic Forest is considered one of the hotspots for conservation, comprising remnants of rain forest along the eastern Brazilian coast. Its native inhabitants in the Southeastern coast include the Caiçaras (descendants from Amerindians and European colonizers), with a deep knowledge on the natural resources used for their livelihood. Methods We studied the use of the terrestrial fauna in three Caiçara communities, through open-ended interviews with 116 native residents. Data were checked through systematic observations and collection of zoological material. Results The dependence on the terrestrial fauna by Caiçaras is especially for food and medicine. The main species used are Didelphis spp., Dasyprocta azarae, Dasypus novemcinctus, and small birds (several species of Turdidae). Contrasting with a high dependency on terrestrial fauna resources by native Amazonians, the Caiçaras do not show a constant dependency on these resources. Nevertheless, the occasional hunting of native animals represents a complimentary source of animal protein. Conclusion Indigenous or local knowledge on native resources is important in order to promote local development in a sustainable way, and can help to conserve biodiversity, particularly if the resource is sporadically used and not commercially exploited. PMID:19930595

  11. Economically motivated adulteration (EMA) of food: common characteristics of EMA incidents.

    PubMed

    Everstine, Karen; Spink, John; Kennedy, Shaun

    2013-04-01

    Economically motivated adulteration (EMA) of food, also known as food fraud, is the intentional adulteration of food for financial advantage. A common form of EMA, undeclared substitution with alternative ingredients, is usually a health concern because of allergen labeling requirements. As demonstrated by the nearly 300,000 illnesses in China from melamine adulteration of infant formula, EMA also has the potential to result in serious public health consequences. Furthermore, EMA incidents reveal gaps in quality assurance testing methodologies that could be exploited for intentional harm. In contrast to foodborne disease outbreaks, EMA incidents present a particular challenge to the food industry and regulators because they are deliberate acts that are intended to evade detection. Large-scale EMA incidents have been described in the scientific literature, but smaller incidents have been documented only in media sources. We reviewed journal articles and media reports of EMA since 1980. We identified 137 unique incidents in 11 food categories: fish and seafood (24 incidents), dairy products (15), fruit juices (12), oils and fats (12), grain products (11), honey and other natural sweeteners (10), spices and extracts (8), wine and other alcoholic beverages (7), infant formula (5), plant-based proteins (5), and other food products (28). We identified common characteristics among the incidents that may help us better evaluate and reduce the risk of EMA. These characteristics reflect the ways in which existing regulatory systems or testing methodologies were inadequate for detecting EMA and how novel detection methods and other deterrence strategies can be deployed. Prevention and detection of EMA cannot depend on traditional food safety strategies. Comprehensive food protection, as outlined by the Food Safety Modernization Act, will require innovative methods for detecting EMA and for targeting crucial resources toward the riskiest food products.

  12. Assessing the land resource–food price nexus of the Sustainable Development Goals

    PubMed Central

    Obersteiner, Michael; Walsh, Brian; Frank, Stefan; Havlík, Petr; Cantele, Matthew; Liu, Junguo; Palazzo, Amanda; Herrero, Mario; Lu, Yonglong; Mosnier, Aline; Valin, Hugo; Riahi, Keywan; Kraxner, Florian; Fritz, Steffen; van Vuuren, Detlef

    2016-01-01

    The 17 Sustainable Development Goals (SDGs) call for a comprehensive new approach to development rooted in planetary boundaries, equity, and inclusivity. The wide scope of the SDGs will necessitate unprecedented integration of siloed policy portfolios to work at international, regional, and national levels toward multiple goals and mitigate the conflicts that arise from competing resource demands. In this analysis, we adopt a comprehensive modeling approach to understand how coherent policy combinations can manage trade-offs among environmental conservation initiatives and food prices. Our scenario results indicate that SDG strategies constructed around Sustainable Consumption and Production policies can minimize problem-shifting, which has long placed global development and conservation agendas at odds. We conclude that Sustainable Consumption and Production policies (goal 12) are most effective at minimizing trade-offs and argue for their centrality to the formulation of coherent SDG strategies. We also find that alternative socioeconomic futures—mainly, population and economic growth pathways—generate smaller impacts on the eventual achievement of land resource–related SDGs than do resource-use and management policies. We expect that this and future systems analyses will allow policy-makers to negotiate trade-offs and exploit synergies as they assemble sustainable development strategies equal in scope to the ambition of the SDGs. PMID:27652336

  13. Host discrimination in modular mutualisms: a theoretical framework for meta-populations of mutualists and exploiters

    PubMed Central

    Steidinger, Brian S.; Bever, James D.

    2016-01-01

    Plants in multiple symbioses are exploited by symbionts that consume their resources without providing services. Discriminating hosts are thought to stabilize mutualism by preferentially allocating resources into anatomical structures (modules) where services are generated, with examples of modules including the entire inflorescences of figs and the root nodules of legumes. Modules are often colonized by multiple symbiotic partners, such that exploiters that co-occur with mutualists within mixed modules can share rewards generated by their mutualist competitors. We developed a meta-population model to answer how the population dynamics of mutualists and exploiters change when they interact with hosts with different module occupancies (number of colonists per module) and functionally different patterns of allocation into mixed modules. We find that as module occupancy increases, hosts must increase the magnitude of preferentially allocated resources in order to sustain comparable populations of mutualists. Further, we find that mixed colonization can result in the coexistence of mutualist and exploiter partners, but only when preferential allocation follows a saturating function of the number of mutualists in a module. Finally, using published data from the fig–wasp mutualism as an illustrative example, we derive model predictions that approximate the proportion of exploiter, non-pollinating wasps observed in the field. PMID:26740613

  14. Origin and diet of the prehistoric hunter-gatherers on the mediterranean island of Favignana (Ègadi Islands, Sicily).

    PubMed

    Mannino, Marcello A; Catalano, Giulio; Talamo, Sahra; Mannino, Giovanni; Di Salvo, Rosaria; Schimmenti, Vittoria; Lalueza-Fox, Carles; Messina, Andrea; Petruso, Daria; Caramelli, David; Richards, Michael P; Sineo, Luca

    2012-01-01

    Hunter-gatherers living in Europe during the transition from the late Pleistocene to the Holocene intensified food acquisition by broadening the range of resources exploited to include marine taxa. However, little is known on the nature of this dietary change in the Mediterranean Basin. A key area to investigate this issue is the archipelago of the Ègadi Islands, most of which were connected to Sicily until the early Holocene. The site of Grotta d'Oriente, on the present-day island of Favignana, was occupied by hunter-gatherers when Postglacial environmental changes were taking place (14,000-7,500 cal BP). Here we present the results of AMS radiocarbon dating, palaeogenetic and isotopic analyses undertaken on skeletal remains of the humans buried at Grotta d'Oriente. Analyses of the mitochondrial hypervariable first region of individual Oriente B, which belongs to the HV-1 haplogroup, suggest for the first time on genetic grounds that humans living in Sicily during the early Holocene could have originated from groups that migrated from the Italian Peninsula around the Last Glacial Maximum. Carbon and nitrogen isotope analyses show that the Upper Palaeolithic and Mesolithic hunter-gatherers of Favignana consumed almost exclusively protein from terrestrial game and that there was only a slight increase in marine food consumption from the late Pleistocene to the early Holocene. This dietary change was similar in scale to that at sites on mainland Sicily and in the rest of the Mediterranean, suggesting that the hunter-gatherers of Grotta d'Oriente did not modify their subsistence strategies specifically to adapt to the progressive isolation of Favignana. The limited development of technologies for intensively exploiting marine resources was probably a consequence both of Mediterranean oligotrophy and of the small effective population size of these increasingly isolated human groups, which made innovation less likely and prevented transmission of fitness-enhancing adaptations.

  15. Origin and Diet of the Prehistoric Hunter-Gatherers on the Mediterranean Island of Favignana (Ègadi Islands, Sicily)

    PubMed Central

    Mannino, Marcello A.; Catalano, Giulio; Talamo, Sahra; Mannino, Giovanni; Di Salvo, Rosaria; Schimmenti, Vittoria; Lalueza-Fox, Carles; Messina, Andrea; Petruso, Daria; Caramelli, David; Richards, Michael P.; Sineo, Luca

    2012-01-01

    Hunter-gatherers living in Europe during the transition from the late Pleistocene to the Holocene intensified food acquisition by broadening the range of resources exploited to include marine taxa. However, little is known on the nature of this dietary change in the Mediterranean Basin. A key area to investigate this issue is the archipelago of the Ègadi Islands, most of which were connected to Sicily until the early Holocene. The site of Grotta d’Oriente, on the present-day island of Favignana, was occupied by hunter-gatherers when Postglacial environmental changes were taking place (14,000-7,500 cal BP). Here we present the results of AMS radiocarbon dating, palaeogenetic and isotopic analyses undertaken on skeletal remains of the humans buried at Grotta d’Oriente. Analyses of the mitochondrial hypervariable first region of individual Oriente B, which belongs to the HV-1 haplogroup, suggest for the first time on genetic grounds that humans living in Sicily during the early Holocene could have originated from groups that migrated from the Italian Peninsula around the Last Glacial Maximum. Carbon and nitrogen isotope analyses show that the Upper Palaeolithic and Mesolithic hunter-gatherers of Favignana consumed almost exclusively protein from terrestrial game and that there was only a slight increase in marine food consumption from the late Pleistocene to the early Holocene. This dietary change was similar in scale to that at sites on mainland Sicily and in the rest of the Mediterranean, suggesting that the hunter-gatherers of Grotta d’Oriente did not modify their subsistence strategies specifically to adapt to the progressive isolation of Favignana. The limited development of technologies for intensively exploiting marine resources was probably a consequence both of Mediterranean oligotrophy and of the small effective population size of these increasingly isolated human groups, which made innovation less likely and prevented transmission of fitness-enhancing adaptations. PMID:23209602

  16. Panmictic and Clonal Evolution on a Single Patchy Resource Produces Polymorphic Foraging Guilds

    PubMed Central

    Getz, Wayne M.; Salter, Richard; Lyons, Andrew J.; Sippl-Swezey, Nicolas

    2015-01-01

    We develop a stochastic, agent-based model to study how genetic traits and experiential changes in the state of agents and available resources influence individuals’ foraging and movement behaviors. These behaviors are manifest as decisions on when to stay and exploit a current resource patch or move to a particular neighboring patch, based on information of the resource qualities of the patches and the anticipated level of intraspecific competition within patches. We use a genetic algorithm approach and an individual’s biomass as a fitness surrogate to explore the foraging strategy diversity of evolving guilds under clonal versus hermaphroditic sexual reproduction. We first present the resource exploitation processes, movement on cellular arrays, and genetic algorithm components of the model. We then discuss their implementation on the Nova software platform. This platform seamlessly combines the dynamical systems modeling of consumer-resource interactions with agent-based modeling of individuals moving over a landscapes, using an architecture that lays transparent the following four hierarchical simulation levels: 1.) within-patch consumer-resource dynamics, 2.) within-generation movement and competition mitigation processes, 3.) across-generation evolutionary processes, and 4.) multiple runs to generate the statistics needed for comparative analyses. The focus of our analysis is on the question of how the biomass production efficiency and the diversity of guilds of foraging strategy types, exploiting resources over a patchy landscape, evolve under clonal versus random hermaphroditic sexual reproduction. Our results indicate greater biomass production efficiency under clonal reproduction only at higher population densities, and demonstrate that polymorphisms evolve and are maintained under random mating systems. The latter result questions the notion that some type of associative mating structure is needed to maintain genetic polymorphisms among individuals exploiting a common patchy resource on an otherwise spatially homogeneous landscape. PMID:26274613

  17. Long-term resilience of late holocene coastal subsistence system in Southeastern South america.

    PubMed

    Colonese, André Carlo; Collins, Matthew; Lucquin, Alexandre; Eustace, Michael; Hancock, Y; de Almeida Rocha Ponzoni, Raquel; Mora, Alice; Smith, Colin; Deblasis, Paulo; Figuti, Levy; Wesolowski, Veronica; Plens, Claudia Regina; Eggers, Sabine; de Farias, Deisi Scunderlick Eloy; Gledhill, Andy; Craig, Oliver Edward

    2014-01-01

    Isotopic and molecular analysis on human, fauna and pottery remains can provide valuable new insights into the diets and subsistence practices of prehistoric populations. These are crucial to elucidate the resilience of social-ecological systems to cultural and environmental change. Bulk collagen carbon and nitrogen isotopic analysis of 82 human individuals from mid to late Holocene Brazilian archaeological sites (∼6,700 to ∼1,000 cal BP) reveal an adequate protein incorporation and, on the coast, the continuation in subsistence strategies based on the exploitation of aquatic resources despite the introduction of pottery and domesticated plant foods. These results are supported by carbon isotope analysis of single amino acid extracted from bone collagen. Chemical and isotopic analysis also shows that pottery technology was used to process marine foods and therefore assimilated into the existing subsistence strategy. Our multidisciplinary results demonstrate the resilient character of the coastal economy to cultural change during the late Holocene in southern Brazil.

  18. Long-Term Resilience of Late Holocene Coastal Subsistence System in Southeastern South America

    PubMed Central

    Colonese, André Carlo; Collins, Matthew; Lucquin, Alexandre; Eustace, Michael; Hancock, Y.; de Almeida Rocha Ponzoni, Raquel; Mora, Alice; Smith, Colin; DeBlasis, Paulo; Figuti, Levy; Wesolowski, Veronica; Plens, Claudia Regina; Eggers, Sabine; de Farias, Deisi Scunderlick Eloy; Gledhill, Andy; Craig, Oliver Edward

    2014-01-01

    Isotopic and molecular analysis on human, fauna and pottery remains can provide valuable new insights into the diets and subsistence practices of prehistoric populations. These are crucial to elucidate the resilience of social-ecological systems to cultural and environmental change. Bulk collagen carbon and nitrogen isotopic analysis of 82 human individuals from mid to late Holocene Brazilian archaeological sites (∼6,700 to ∼1,000 cal BP) reveal an adequate protein incorporation and, on the coast, the continuation in subsistence strategies based on the exploitation of aquatic resources despite the introduction of pottery and domesticated plant foods. These results are supported by carbon isotope analysis of single amino acid extracted from bone collagen. Chemical and isotopic analysis also shows that pottery technology was used to process marine foods and therefore assimilated into the existing subsistence strategy. Our multidisciplinary results demonstrate the resilient character of the coastal economy to cultural change during the late Holocene in southern Brazil. PMID:24718458

  19. The possibility of increasing the efficiency of accessible coal deposits by optimizing dimensions of protective pillars or the scope of exploitation

    NASA Astrophysics Data System (ADS)

    Bańka, Piotr; Badura, Henryk; Wesołowski, Marek

    2017-11-01

    One of the ways to protect objects exposed to the influences of mining exploitation is establishing protective pillars for them. Properly determined pillar provides effective protection of the object for which it was established. Determining correct dimensions of a pillar requires taking into account contradictory requirements. Protection measures against the excessive influences of mining exploitation require designing the largest possible pillars, whereas economic requirements suggest a maximum reduction of the size of resources left in the pillar. This paper presents algorithms and programs developed for determining optimal dimensions of protective pillars for surface objects and shafts. The issue of designing a protective pillar was treated as a nonlinear programming task. The objective function are the resources left in a pillar while nonlinear limitations are the deformation values evoked by the mining exploitation. Resources in the pillar may be weighted e.g. by calorific value or by the inverse of output costs. The possibility of designing pillars of any polygon shape was taken into account. Because of the applied exploitation technologies the rectangular pillar shape should be considered more advantageous than the oval one, though it does not ensure the minimization of resources left in a pillar. In this article there is also presented a different approach to the design of protective pillars, which instead of fixing the pillar boundaries in subsequent seams, the length of longwall panels of the designed mining exploitation is limited in a way that ensures the effective protection of an object while maximizing the extraction ratio of the deposit.

  20. Self-organized discrimination of resources.

    PubMed

    Campo, Alexandre; Garnier, Simon; Dédriche, Olivier; Zekkri, Mouhcine; Dorigo, Marco

    2011-01-01

    When selecting a resource to exploit, an insect colony must take into account at least two constraints: the resource must be abundant enough to sustain the whole group, but not too large to limit exploitation costs, and risks of conflicts with other colonies. Following recent results on cockroaches and ants, we introduce here a behavioral mechanism that satisfies these two constraints. Individuals simply modulate their probability to switch to another resource as a function of the local density of conspecifics locally detected. As a result, the individuals gather at the smallest resource that can host the whole group, hence reducing competition and exploitation costs while fulfilling the overall group's needs. Our analysis reveals that the group becomes better at discriminating between similar resources as it grows in size. Also, the discrimination mechanism is flexible and the group readily switches to a better suited resource as it appears in the environment. The collective decision emerges through the self-organization of individuals, that is, in absence of any centralized control. It also requires a minimal individual cognitive investment, making the proposed mechanism likely to occur in other social species and suitable for the development of distributed decision making tools.

  1. Self-Organized Discrimination of Resources

    PubMed Central

    Campo, Alexandre; Garnier, Simon; Dédriche, Olivier; Zekkri, Mouhcine; Dorigo, Marco

    2011-01-01

    When selecting a resource to exploit, an insect colony must take into account at least two constraints: the resource must be abundant enough to sustain the whole group, but not too large to limit exploitation costs, and risks of conflicts with other colonies. Following recent results on cockroaches and ants, we introduce here a behavioral mechanism that satisfies these two constraints. Individuals simply modulate their probability to switch to another resource as a function of the local density of conspecifics locally detected. As a result, the individuals gather at the smallest resource that can host the whole group, hence reducing competition and exploitation costs while fulfilling the overall group's needs. Our analysis reveals that the group becomes better at discriminating between similar resources as it grows in size. Also, the discrimination mechanism is flexible and the group readily switches to a better suited resource as it appears in the environment. The collective decision emerges through the self-organization of individuals, that is, in absence of any centralized control. It also requires a minimal individual cognitive investment, making the proposed mechanism likely to occur in other social species and suitable for the development of distributed decision making tools. PMID:21625643

  2. The second green revolution? Production of plant-based biodegradable plastics.

    PubMed

    Mooney, Brian P

    2009-03-01

    Biodegradable plastics are those that can be completely degraded in landfills, composters or sewage treatment plants by the action of naturally occurring micro-organisms. Truly biodegradable plastics leave no toxic, visible or distinguishable residues following degradation. Their biodegradability contrasts sharply with most petroleum-based plastics, which are essentially indestructible in a biological context. Because of the ubiquitous use of petroleum-based plastics, their persistence in the environment and their fossil-fuel derivation, alternatives to these traditional plastics are being explored. Issues surrounding waste management of traditional and biodegradable polymers are discussed in the context of reducing environmental pressures and carbon footprints. The main thrust of the present review addresses the development of plant-based biodegradable polymers. Plants naturally produce numerous polymers, including rubber, starch, cellulose and storage proteins, all of which have been exploited for biodegradable plastic production. Bacterial bioreactors fed with renewable resources from plants--so-called 'white biotechnology'--have also been successful in producing biodegradable polymers. In addition to these methods of exploiting plant materials for biodegradable polymer production, the present review also addresses the advances in synthesizing novel polymers within transgenic plants, especially those in the polyhydroxyalkanoate class. Although there is a stigma associated with transgenic plants, especially food crops, plant-based biodegradable polymers, produced as value-added co-products, or, from marginal land (non-food), crops such as switchgrass (Panicum virgatum L.), have the potential to become viable alternatives to petroleum-based plastics and an environmentally benign and carbon-neutral source of polymers.

  3. Distinct Urban Mines: Exploiting secondary resources in unique anthropogenic spaces.

    PubMed

    Ongondo, F O; Williams, I D; Whitlock, G

    2015-11-01

    Fear of scarcity of resources highlight the need to exploit secondary materials from urban mines in the anthroposphere. Analogous to primary mines rich in one type of material (e.g. copper, gold, etc.), some urban mines are unique/distinct. We introduce, illustrate and discuss the concept of Distinct Urban Mines (DUM). Using the example of a university DUM in the UK, analogous to a primary mine, we illustrate potential product/material yields in respect of size, concentration and spatial location of the mine. Product ownership and replacement cycles for 17 high-value electrical and electronic equipment (EEE) among students showed that 20 tonnes of valuable e-waste were in stockpile in this DUM and a further 87 tonnes would 'soon' be available for exploitation. We address the opportunities and challenges of exploiting DUMs and conclude that they are readily available reservoirs for resource recovery. Two original contributions arise from this work: (i) a novel approach to urban mining with a potential for maximising resource recovery within the anthroposphere is conceptualised; and (ii) previously unavailable data for high-value products for a typical university DUM are presented and analysed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. The ethics of commercial surrogate mothering: a response to Casey Humbyrd.

    PubMed

    Omonzejele, Peter F

    2011-01-01

    This article critically examines the argument advanced by Casey Humbyrd in support of international commercial surrogate mothering. It finds her arguments unconvincing especially at the point of implementation. This is because the author was unable to demonstrate how regulation and her notion offair compensation would not lead to undue inducement and exploitation in resource-poor settings where urgent needs often exist. In fact, the argument advanced in this article is that commercial surrogate mothering cannot but be exploitative in so far as urgent and compelling needs exist. To logically drive home this point, the elements of exploitation were discussed in order to show that regulation and fair compensation cannot prevent exploitative transaction in commercial surrogate mothering arrangements. This may happen in the same way as regulation and compensation framework have not been successful in preventing the allegations of exploitation in the research context especially where studies are conducted in resource-poor countries.

  5. Ecosystem Services: a Framework for Environmental Management of the Deep Sea

    NASA Astrophysics Data System (ADS)

    Le, J. T.; Levin, L. A.; Carson, R. T.

    2016-02-01

    As demand for deep-sea resources rapidly expands in the food, energy, mineral, and pharmaceutical sectors, it has become increasingly clear that a regulatory structure for extracting these resources is not yet in place. There are jurisdictional gaps and a lack of regulatory consistency regarding what aspects of the deep sea need protection and what requirements might help guarantee that protection. Given the mining sector's intent to exploit seafloor massive sulphides, Mn nodules, cobalt crusts, and phosphorites in the coming years, there is an urgent need for deep-ocean environmental management. Here, we propose an ecosystem services-based framework to inform decisions and best practices regarding resource exploitation, and to guide baseline studies, preventative actions, monitoring, and remediation. With policy in early stages of development, an ecosystem services approach has the potential to serve as an overarching framework that takes protection of natural capital provided by the environment into account during the decision-making process. We show how an ecosystem services approach combined with economic tools, such as benefit transfer techniques, should help illuminate issues where there are direct conflicts among different industries, and between industry and conservation. We argue for baseline and monitoring measurements and metrics that inform about deep-sea ecosystem services that would be impaired by mining, and discuss ways to incorporate the value of those losses into decision making, mitigation measures, and ultimately product costs. This proposal is considered relative to current International Seabed Authority recommendations and contractor practices, and new actions are proposed. An ecosystem services-based understanding of how these systems work and their value to society can improve sustainability and stewardship of the deep ocean.

  6. Land Snails as a Diet Diversification Proxy during the Early Upper Palaeolithic in Europe

    PubMed Central

    Fernández-López de Pablo, Javier; Badal, Ernestina; Ferrer García, Carlos; Martínez-Ortí, Alberto; Sanchis Serra, Alfred

    2014-01-01

    Despite the ubiquity of terrestrial gastropods in the Late Pleistocene and Holocene archaeological record, it is still unknown when and how this type of invertebrate resource was incorporated into human diets. In this paper, we report the oldest evidence of land snail exploitation as a food resource in Europe dated to 31.3-26.9 ka yr cal BP from the recently discovered site of Cova de la Barriada (eastern Iberian Peninsula). Mono-specific accumulations of large Iberus alonensis land snails (Ferussac 1821) were found in three different archaeological levels in association with combustion structures, along with lithic and faunal assemblages. Using a new analytical protocol based on taphonomic, microX-Ray Diffractometer (DXR) and biometric analyses, we investigated the patterns of selection, consumption and accumulation of land snails at the site. The results display a strong mono-specific gathering of adult individuals, most of them older than 55 weeks, which were roasted in ambers of pine and juniper under 375°C. This case study uncovers new patterns of invertebrate exploitation during the Gravettian in southwestern Europe without known precedents in the Middle Palaeolithic nor the Aurignacian. In the Mediterranean context, such an early occurrence contrasts with the neighbouring areas of Morocco, France, Italy and the Balkans, where the systematic nutritional use of land snails appears approximately 10,000 years later during the Iberomaurisian and the Late Epigravettian. The appearance of this new subsistence activity in the eastern and southern regions of Spain was coeval to other demographically driven transformations in the archaeological record, suggesting different chronological patterns of resource intensification and diet broadening along the Upper Palaeolithic in the Mediterranean basin. PMID:25141047

  7. Land snails as a diet diversification proxy during the early upper palaeolithic in Europe.

    PubMed

    Fernández-López de Pablo, Javier; Badal, Ernestina; Ferrer García, Carlos; Martínez-Ortí, Alberto; Sanchis Serra, Alfred

    2014-01-01

    Despite the ubiquity of terrestrial gastropods in the Late Pleistocene and Holocene archaeological record, it is still unknown when and how this type of invertebrate resource was incorporated into human diets. In this paper, we report the oldest evidence of land snail exploitation as a food resource in Europe dated to 31.3-26.9 ka yr cal BP from the recently discovered site of Cova de la Barriada (eastern Iberian Peninsula). Mono-specific accumulations of large Iberus alonensis land snails (Ferussac 1821) were found in three different archaeological levels in association with combustion structures, along with lithic and faunal assemblages. Using a new analytical protocol based on taphonomic, microX-Ray Diffractometer (DXR) and biometric analyses, we investigated the patterns of selection, consumption and accumulation of land snails at the site. The results display a strong mono-specific gathering of adult individuals, most of them older than 55 weeks, which were roasted in ambers of pine and juniper under 375°C. This case study uncovers new patterns of invertebrate exploitation during the Gravettian in southwestern Europe without known precedents in the Middle Palaeolithic nor the Aurignacian. In the Mediterranean context, such an early occurrence contrasts with the neighbouring areas of Morocco, France, Italy and the Balkans, where the systematic nutritional use of land snails appears approximately 10,000 years later during the Iberomaurisian and the Late Epigravettian. The appearance of this new subsistence activity in the eastern and southern regions of Spain was coeval to other demographically driven transformations in the archaeological record, suggesting different chronological patterns of resource intensification and diet broadening along the Upper Palaeolithic in the Mediterranean basin.

  8. Rapid Global Expansion of Invertebrate Fisheries: Trends, Drivers, and Ecosystem Effects

    PubMed Central

    Anderson, Sean C.; Mills Flemming, Joanna; Watson, Reg; Lotze, Heike K.

    2011-01-01

    Background Worldwide, finfish fisheries are receiving increasing assessment and regulation, slowly leading to more sustainable exploitation and rebuilding. In their wake, invertebrate fisheries are rapidly expanding with little scientific scrutiny despite increasing socio-economic importance. Methods and Findings We provide the first global evaluation of the trends, drivers, and population and ecosystem consequences of invertebrate fisheries based on a global catch database in combination with taxa-specific reviews. We also develop new methodologies to quantify temporal and spatial trends in resource status and fishery development. Since 1950, global invertebrate catches have increased 6-fold with 1.5 times more countries fishing and double the taxa reported. By 2004, 34% of invertebrate fisheries were over-exploited, collapsed, or closed. New fisheries have developed increasingly rapidly, with a decrease of 6 years (3 years) in time to peak from the 1950s to 1990s. Moreover, some fisheries have expanded further and further away from their driving market, encompassing a global fishery by the 1990s. 71% of taxa (53% of catches) are harvested with habitat-destructive gear, and many provide important ecosystem functions including habitat, filtration, and grazing. Conclusions Our findings suggest that invertebrate species, which form an important component of the basis of marine food webs, are increasingly exploited with limited stock and ecosystem-impact assessments, and enhanced management attention is needed to avoid negative consequences for ocean ecosystems and human well-being. PMID:21408090

  9. Human exploitation assisting a threatened species? The case of muttonbirders and Buller’s albatross

    PubMed Central

    Poupart, Timothée A.; Miskelly, Colin M.; Stahl, Jean-Claude; Arnould, John P. Y.

    2017-01-01

    Albatrosses are flexible and adaptable predators, relying on live prey as well as carrion. Use of predictable food sources and reliance on human-produced resources are well-known trait in long-range feeders like albatrosses and petrels. Breeding Buller’s albatrosses studied at Solander I. (Hautere), New Zealand fed their chicks the remains of sooty shearwater juveniles (tītī in Māori), which are harvested from nearby muttonbirding sites. Evidence of this food type was found at over 10% of nests examined, and 17–40% birds that were fitted with GPS loggers visited muttonbirding sites in this and previous studies. Muttonbirding is a traditional practice that has continued for centuries, with up to 120 tonnes of offal discharged to the sea annually during the present day harvest. It coincides with the energetically-demanding early chick period for the albatrosses. Our finding suggests that the offal may be an important, but overlooked element in the albatross diet. As an important supplementary food for the albatrosses it is likely to have contributed to the 3% per annum growth of their populations since the first comprehensive population surveys in 1969. PMID:28406981

  10. Feeding by coral reef mesograzers: algae or cyanobacteria?

    NASA Astrophysics Data System (ADS)

    Cruz-Rivera, Edwin; Paul, Valerie J.

    2006-11-01

    Marine studies on herbivory have addressed the role of algae as food and shelter for small consumers, but the potential of benthic cyanobacteria to play similar roles is largely unknown. Here, feeding preferences were measured for eight invertebrate consumers from Guam, offered four common macroalgae and two cyanobacteria. The survivorship of another consumer raised on either macroalgae or cyanobacteria was also assessed. From the choices offered, the sacoglossans Elysia rufescens and E. ornata consumed the green macroalga Bryopsis pennata. The crab Menaethius monoceros preferred the red alga Acanthophora spicifera. The amphipods Parhyale hawaiensis and Cymadusa imbroglio consumed macroalgae and cyanobacteria in equivalent amounts, with C. imbroglio showing less selectivity among diets. In contrast to these patterns, in these assays the gastropods Stylocheilus striatus, Haminoea cymbalum, H. ovalis, and Haminoea sp. fed exclusively, or survived only, on cyanobacteria. Preferences for different cyanobacteria varied. Field surveys of cyanobacteria-associated species yielded 34 different invertebrate taxa and suggested different degrees of specificity in these associations. Tropical mesograzers exploit considerably different food resources, with some species adapted to consume cyanobacterial mats. Benthic cyanobacteria may play important roles as food and shelter for marine consumers and may indirectly influence local biodiversity through their associated fauna.

  11. Resource Consumption and Environmental Impacts of the Agrofood Sector: Life Cycle Assessment of Italian Citrus-Based Products

    NASA Astrophysics Data System (ADS)

    Beccali, Marco; Cellura, Maurizio; Iudicello, Maria; Mistretta, Marina

    2009-04-01

    Food production and consumption cause significant environmental burdens during the product life cycles. As a result of intensive development and the changing social attitudes and behaviors in the last century, the agrofood sector is the highest resource consumer after housing in the EU. This paper is part of an effort to estimate environmental impacts associated with life cycles of the agrofood chain, such as primary energy consumption, water exploitation, and global warming. Life cycle assessment is used to investigate the production of the following citrus-based products in Italy: essential oil, natural juice, and concentrated juice from oranges and lemons. The related process flowcharts, the relevant mass and energy flows, and the key environmental issues are identified for each product. This paper represents one of the first studies on the environmental impacts from cradle to gate for citrus products in order to suggest feasible strategies and actions to improve their environmental performance.

  12. Resource consumption and environmental impacts of the agrofood sector: life cycle assessment of italian citrus-based products.

    PubMed

    Beccali, Marco; Cellura, Maurizio; Iudicello, Maria; Mistretta, Marina

    2009-04-01

    Food production and consumption cause significant environmental burdens during the product life cycles. As a result of intensive development and the changing social attitudes and behaviors in the last century, the agrofood sector is the highest resource consumer after housing in the EU. This paper is part of an effort to estimate environmental impacts associated with life cycles of the agrofood chain, such as primary energy consumption, water exploitation, and global warming. Life cycle assessment is used to investigate the production of the following citrus-based products in Italy: essential oil, natural juice, and concentrated juice from oranges and lemons. The related process flowcharts, the relevant mass and energy flows, and the key environmental issues are identified for each product. This paper represents one of the first studies on the environmental impacts from cradle to gate for citrus products in order to suggest feasible strategies and actions to improve their environmental performance.

  13. Neanderthal exploitation of marine mammals in Gibraltar

    PubMed Central

    Stringer, C. B.; Finlayson, J. C.; Barton, R. N. E.; Fernández-Jalvo, Y.; Cáceres, I.; Sabin, R. C.; Rhodes, E. J.; Currant, A. P.; Rodríguez-Vidal, J.; Giles-Pacheco, F.; Riquelme-Cantal, J. A.

    2008-01-01

    Two coastal sites in Gibraltar, Vanguard and Gorham's Caves, located at Governor's Beach on the eastern side of the Rock, are especially relevant to the study of Neanderthals. Vanguard Cave provides evidence of marine food supply (mollusks, seal, dolphin, and fish). Further evidence of marine mammal remains was also found in the occupation levels at Gorham's Cave associated with Upper Paleolithic and Mousterian technologies [Finlayson C, et al. (2006) Nature 443:850–853]. The stratigraphic sequence of Gibraltar sites allows us to compare behaviors and subsistence strategies of Neanderthals during the Middle Paleolithic observed at Vanguard and Gorham's Cave sites. This evidence suggests that such use of marine resources was not a rare behavior and represents focused visits to the coast and estuaries. PMID:18809913

  14. Knowledge Management to Exploit Agrarian Resources as Part of Late-Eighteenth-Century Cultures of Innovation: Friedrich Casimir Medicus and Franz Von Paula Schrank

    ERIC Educational Resources Information Center

    Popplow, Marcus

    2012-01-01

    This essay contributes to a recent strain of research that questions clear-cut dichotomies between "scientists" and "artisans" in the early modern period. With a focus on the exploitation of agrarian resources, it argues for the appreciation of a more complex panorama of intersecting knowledge systems spanning from botany as…

  15. Rational Exploitation and Utilizing of Groundwater in Jiangsu Coastal Area

    NASA Astrophysics Data System (ADS)

    Kang, B.; Lin, X.

    2017-12-01

    Jiangsu coastal area is located in the southeast coast of China, where is a new industrial base and an important coastal and Land Resources Development Zone of China. In the areas with strong human exploitation activities, regional groundwater evolution is obviously affected by human activities. In order to solve the environmental geological problems caused by groundwater exploitation fundamentally, we must find out the forming conditions of regional groundwater hydrodynamic field, and the impact of human activities on groundwater hydrodynamic field evolution and hydrogeochemical evolition. Based on these results, scientific management and reasonable exploitation of the regional groundwater resources can be provided for the utilization. Taking the coastal area of Jiangsu as the research area, we investigate and analyze of the regional hydrogeological conditions. The numerical simulation model of groundwater flow was established according to the water power, chemical and isotopic methods, the conditions of water flow and the influence of hydrodynamic field on the water chemical field. We predict the evolution of regional groundwater dynamics under the influence of human activities and climate change and evaluate the influence of groundwater dynamic field evolution on the environmental geological problems caused by groundwater exploitation under various conditions. We get the following conclusions: Three groundwater exploitation optimal schemes were established. The groundwater salinization was taken as the primary control condition. The substitution model was proposed to model groundwater exploitation and water level changes by BP network method.Then genetic algorithm was used to solve the optimization solution. Three groundwater exploitation optimal schemes were submit to local water resource management. The first sheme was used to solve the groundwater salinization problem. The second sheme focused on dual water supply. The third sheme concerned on emergency water supppy. This is the first time environment problem taken as water management objectinve in this coastal area.

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

    PubMed

    Morissette, Lyne; Christensen, Villy; Pauly, Daniel

    2012-01-01

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

  17. Re-thinking the unimpeded tube-well growth under the depleting groundwater resources in the Punjab, Pakistan

    NASA Astrophysics Data System (ADS)

    Watto, Muhammad Arif; Mugera, Amin W.; Kingwell, Ross; Saqab, Muhammad Mudasar

    2018-04-01

    Groundwater resources are crucial in sustaining agro-ecosystems and ensuring food security in many parts of the world, including Pakistan. However, the sustainability of groundwater resources is subject to a number of challenges, including over-extraction, deterioration in quality, and vulnerability to the impacts of climate change and population growth. Given the current state of groundwater resources in Pakistan, policymakers seek to manage groundwater resources by limiting groundwater extraction. To achieve this goal on a national scale, it is important to understand the determinants of the decisions made by local farmers in respect of tube-well adoption. This study investigates smallholder farmers' decisions to adopt tube-well technology in the face of dwindling groundwater resources and falling water tables. Analysis is based on a cross-sectional survey of 200 rural households from the arid to semi-arid predominantly groundwater-irrigated plains of the Punjab province, Pakistan. It is found that farmers will adopt tube-well technology in pursuit of reliable irrigation water supplies to hedge against production risks but not against the risk associated with unfavourable extreme events (downside risk) such as total crop failure. This suggests that the adoption decision is influenced by the expected long-term rather than the short-term benefits. This paper draws attention to the need to regulate groundwater resource exploitation by requiring the use of tube-well technology to be accompanied by irrigation water-efficient techniques and technologies.

  18. Exploiting opportunistic resources for ATLAS with ARC CE and the Event Service

    NASA Astrophysics Data System (ADS)

    Cameron, D.; Filipčič, A.; Guan, W.; Tsulaia, V.; Walker, R.; Wenaus, T.; ATLAS Collaboration

    2017-10-01

    With ever-greater computing needs and fixed budgets, big scientific experiments are turning to opportunistic resources as a means to add much-needed extra computing power. These resources can be very different in design from those that comprise the Grid computing of most experiments, therefore exploiting them requires a change in strategy for the experiment. They may be highly restrictive in what can be run or in connections to the outside world, or tolerate opportunistic usage only on condition that tasks may be terminated without warning. The Advanced Resource Connector Computing Element (ARC CE) with its nonintrusive architecture is designed to integrate resources such as High Performance Computing (HPC) systems into a computing Grid. The ATLAS experiment developed the ATLAS Event Service (AES) primarily to address the issue of jobs that can be terminated at any point when opportunistic computing capacity is needed by someone else. This paper describes the integration of these two systems in order to exploit opportunistic resources for ATLAS in a restrictive environment. In addition to the technical details, results from deployment of this solution in the SuperMUC HPC centre in Munich are shown.

  19. Commercial sexual exploitation and sex trafficking of children in the United States.

    PubMed

    Greenbaum, V Jordan

    2014-10-01

    Child commercial sexual exploitation and sex trafficking are global health problems requiring a multidisciplinary approach by individuals, organizations, communities, and national governments. The adverse emotional, physical, and social consequences for victims are legion and in many areas of the United States and the rest of the world, victim resources are scarce. Since violence, deprivation, abuse, and infection are so integral to the exploitation experience, victims may present for care to community and academic pediatric and adolescent health care providers. It is essential that medical professionals have the knowledge, skills, and resources to recognize victims, assess their needs, and treat them appropriately, including making key referrals for community services. However, to date medical information and resources regarding commercial sexual exploitation and sex trafficking has been sparse. There are no clinically validated screening tools specifically designed to identify victims in the health care setting and since victims seldom self-identify, it is likely that the majority of victims are unrecognized. The opportunity for comprehensive assessment and intervention is lost. Further, professionals receive little training on appropriate interview techniques for this special population, and many are ill equipped to ensure safety and optimal medical evaluation during the visit. This article provides a general overview of child sex trafficking and commercial sexual exploitation (CSEC), describing the epidemiology of international and domestic exploitation, and reviewing the challenges of conducting research on this population. The five stages of trafficking are explained, as are typical physical and emotional consequences of exploitation. The medical evaluation is described, including potential indicators of CSEC and sex trafficking, common medical presentations by victims, approaches to the comprehensive medical interview, and the appropriate medical exam with diagnostic testing and treatment. Finally, a discussion of common victim needs is provided, with a description of resources and referrals. Copyright © 2014 Mosby, Inc. All rights reserved.

  20. Study of geohazards in the artisanal exploitation sites and their impacts on their surrounding areas. Cases of Mufwa and Kalimbi mines in the South Kivu province (D.R. Congo)

    NASA Astrophysics Data System (ADS)

    Nshokano, Jean-Robert

    2014-05-01

    Kivu region is located in the eastern part of DR Congo. This region is in western branch of the East African Rift. In this region there is a presence of several mineral resources. It is also a sismic zone with many cases of geohazards. Very often international NGO's (Human rights, Green Peace, etc.) consider the illegal mining exploitations as the causes of conflicts and war in that region. Those illegal mining exploitations are also responsible for the insecure and inconvenient situations in the region. The DR Congo is a country with great mining vocation and remarkable geological diversity, its people has the need and the right to understand the different challenges related to geological resources. So it's up to raise the question: "What about the unsubstitutable links which put the life beings and their physical environment, what about the interest of soil and subsoil in the human subsistence and comfort?" In undertaking natural resource exploitation, extreme comfort and ultra capitalism should not blind people. They are called to preserve a nature for all and a nature for future generations. We have a common earth where we exploit all the mineral resources. It's up to everyone as human being to be aware of our responsibility regarding to the irreversible decrease of mineral resources and the constant danger of geohazards. The project'"Earth and life" essentially aims for the strengthening of efforts in geoeducation and mass geocommunication (information and sensitization) about the challenges of oil and mineral resources on one hand, and on the other hand the natural hazards in the perspective to encourage much more a sustainable development. Through fieldwork investigations (geological survey), we are going to map the artisanal exploitation sites targeted by the project. We will proceed by sensitization and mass information about different topics of geology and mineral resources issues in the region. The fieldworks will allow us to make an inventory of different geohazards in urban and rural areas. These works will be recorded in monthly reports. Informations will be disseminated through a specific program of activities (audiovisual broadcasts, monthly reports posted to internet, conferences, workshops, etc.).

  1. Competition in size-structured populations: mechanisms inducing cohort formation and population cycles.

    PubMed

    de Roos, André M; Persson, Lennart

    2003-02-01

    In this paper we investigate the consequences of size-dependent competition among the individuals of a consumer population by analyzing the dynamic properties of a physiologically structured population model. Only 2 size-classes of individuals are distinguished: juveniles and adults. Juveniles and adults both feed on one and the same resource and hence interact by means of exploitative competition. Juvenile individuals allocate all assimilated energy into development and mature on reaching a fixed developmental threshold. The combination of this fixed threshold and the resource-dependent developmental rate, implies that the juvenile delay between birth and the onset of reproduction may vary in time. Adult individuals allocate all assimilated energy to reproduction. Mortality of both juveniles and adults is assumed to be inversely proportional to the amount of energy assimilated. In this setting we study how the dynamics of the population are influenced by the relative foraging capabilities of juveniles and adults. In line with results that we previously obtained in size-structured consumer-resource models with pulsed reproduction, population cycles primarily occur when either juveniles or adults have a distinct competitive advantage. When adults have a larger per capita feeding rate and are hence competitively superior to juveniles, population oscillations occur that are primarily induced by the fact that the duration of the juvenile period changes with changing food conditions. These cycles do not occur when the juvenile delay is a fixed parameter. When juveniles are competitively superior, two different types of population fluctuations can occur: (1) rapid, low-amplitude fluctuations having a period of half the juvenile delay and (2) slow, large-amplitude fluctuations characterized by a period, which is roughly equal to the juvenile delay. The analysis of simplified versions of the structured model indicates that these two types of oscillations also occur if mortality and/or development is independent of food density, i.e. in a situation with a constant juvenile developmental delay and a constant, food-independent background mortality. Thus, the oscillations that occur when juveniles are more competitive are induced by the juvenile delay per se. When juveniles exert a larger foraging pressure on the shared resource, maturation implies an increase not only in adult density, but also in food density and consequently fecundity. Our analysis suggests that this correlation in time between adult density and fecundity is crucial for the occurrence of population cycles when juveniles are competitively superior.

  2. Exploiting Dark Information Resources to Create New Value Added Services to Study Earth Science Phenomena

    NASA Technical Reports Server (NTRS)

    Ramachandran, Rahul; Maskey, Manil; Li, Xiang; Bugbee, Kaylin

    2017-01-01

    This paper presents two research applications exploiting unused metadata resources in novel ways to aid data discovery and exploration capabilities. The results based on the experiments are encouraging and each application has the potential to serve as a useful standalone component or service in a data system. There were also some interesting lessons learned while designing the two applications and these are presented next.

  3. Potentially exploitable supercritical geothermal resources in the ductile crust

    USGS Publications Warehouse

    Watanabe, Noriaki; Numakura, Tatsuya; Sakaguchi, Kiyotoshi; Saishu, Hanae; Okamoto, Atsushi; Ingebritsen, Steven E.; Tsuchiya, Noriyoshi

    2017-01-01

    The hypothesis that the brittle–ductile transition (BDT) drastically reduces permeability implies that potentially exploitable geothermal resources (permeability >10−16 m2) consisting of supercritical water could occur only in rocks with unusually high transition temperatures such as basalt. However, tensile fracturing is possible even in ductile rocks, and some permeability–depth relations proposed for the continental crust show no drastic permeability reduction at the BDT. Here we present experimental results suggesting that the BDT is not the first-order control on rock permeability, and that potentially exploitable resources may occur in rocks with much lower BDT temperatures, such as the granitic rocks that comprise the bulk of the continental crust. We find that permeability behaviour for fractured granite samples at 350–500 °C under effective confining stress is characterized by a transition from a weakly stress-dependent and reversible behaviour to a strongly stress-dependent and irreversible behaviour at a specific, temperature-dependent effective confining stress level. This transition is induced by onset of plastic normal deformation of the fracture surface (elastic–plastic transition) and, importantly, causes no ‘jump’ in the permeability. Empirical equations for this permeability behaviour suggest that potentially exploitable resources exceeding 450 °C may form at depths of 2–6 km even in the nominally ductile crust.

  4. Games of corruption in preventing the overuse of common-pool resources.

    PubMed

    Lee, Joung-Hun; Jusup, Marko; Iwasa, Yoh

    2017-09-07

    Maintaining human cooperation in the context of common-pool resource management is extremely important because otherwise we risk overuse and corruption. To analyse the interplay between economic and ecological factors leading to corruption, we couple the resource dynamics and the evolutionary dynamics of strategic decision making into a powerful analytical framework. The traits of this framework are: (i) an arbitrary number of harvesters share the responsibility to sustainably exploit a specific part of an ecosystem, (ii) harvesters face three strategic choices for exploiting the resource, (iii) a delegated enforcement system is available if called upon, (iv) enforcers are either honest or corrupt, and (v) the resource abundance reflects the choice of harvesting strategies. The resulting dynamical system is bistable; depending on the initial conditions, it evolves either to cooperative (sustainable exploitation) or defecting (overexploitation) equilibria. Using the domain of attraction to cooperative equilibria as an indicator of successful management, we find that the more resilient the resource (as implied by a high growth rate), the more likely the dominance of corruption which, in turn, suppresses the cooperative outcome. A qualitatively similar result arises when slow resource dynamics relative to the dynamics of decision making mask the benefit of cooperation. We discuss the implications of these results in the context of managing common-pool resources. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Land Use Influences Niche Size and the Assimilation of Resources by Benthic Macroinvertebrates in Tropical Headwater Streams

    PubMed Central

    Parreira de Castro, Diego Marcel; Reis de Carvalho, Débora; Pompeu, Paulo dos Santos; Moreira, Marcelo Zacharias; Nardoto, Gabriela Bielefeld; Callisto, Marcos

    2016-01-01

    It is well recognized that assemblage structure of stream macroinvertebrates changes with alterations in catchment or local land use. Our objective was to understand how the trophic ecology of benthic macroinvertebrate assemblages responds to land use changes in tropical streams. We used the isotope methodology to assess how energy flow and trophic relations among macroinvertebrates were affected in environments affected by different land uses (natural cover, pasture, sugar cane plantation). Macroinvertebrates were sampled and categorized into functional feeding groups, and available trophic resources were sampled and evaluated for the isotopic composition of 13C and 15N along streams located in the Cerrado (neotropical savanna). Streams altered by pasture or sugar cane had wider and more overlapped trophic niches, which corresponded to more generalist feeding habits. In contrast, trophic groups in streams with native vegetation had narrower trophic niches with smaller overlaps, suggesting greater specialization. Pasture sites had greater ranges of resources exploited, indicating higher trophic diversity than sites with natural cover and sugar cane plantation. We conclude that agricultural land uses appears to alter the food base and shift macroinvertebrate assemblages towards more generalist feeding behaviors and greater overlap of the trophic niches. PMID:26934113

  6. Are sick individuals weak competitors? Competitive ability of snails parasitized by a gigantism-inducing trematode.

    PubMed

    Seppälä, Otto; Karvonen, Anssi; Kuosa, Marja; Haataja, Maarit; Jokela, Jukka

    2013-01-01

    Parasitized individuals are often expected to be poor competitors because they are weakened by infections. Many trematode species, however, although extensively exploiting their mollusc hosts, also induce gigantism (increased host size) by diverting host resources towards growth instead of reproduction. In such systems, alternatively to reduced competitive ability due to negative effects of parasitism on host performance, larger size could allow more efficient resource acquisition and thus increase the relative competitive ability of host individuals. We addressed this hypothesis by testing the effect of a trematode parasite Diplostomum pseudospathaceum on the competitive ability of its snail host Lymnaea stagnalis. We experimentally examined the growth of snails kept in pairs in relation to their infection status and intensity of resource competition (i.e. food availability). We found that parasitized snails grew faster and their reproduction was reduced compared to unparasitized individuals indicating parasite-induced gigantism. However, growth of the snails was faster when competing with parasitized individuals compared to unparasitized snails indicating reduced competitive ability due to parasitism. The latter effect, however, was relatively weak suggesting that the effects of the parasite on snail physiology may partly override each other in determining competitive ability.

  7. Land Use Influences Niche Size and the Assimilation of Resources by Benthic Macroinvertebrates in Tropical Headwater Streams.

    PubMed

    Parreira de Castro, Diego Marcel; Reis de Carvalho, Débora; Pompeu, Paulo dos Santos; Moreira, Marcelo Zacharias; Nardoto, Gabriela Bielefeld; Callisto, Marcos

    2016-01-01

    It is well recognized that assemblage structure of stream macroinvertebrates changes with alterations in catchment or local land use. Our objective was to understand how the trophic ecology of benthic macroinvertebrate assemblages responds to land use changes in tropical streams. We used the isotope methodology to assess how energy flow and trophic relations among macroinvertebrates were affected in environments affected by different land uses (natural cover, pasture, sugar cane plantation). Macroinvertebrates were sampled and categorized into functional feeding groups, and available trophic resources were sampled and evaluated for the isotopic composition of 13C and 15N along streams located in the Cerrado (neotropical savanna). Streams altered by pasture or sugar cane had wider and more overlapped trophic niches, which corresponded to more generalist feeding habits. In contrast, trophic groups in streams with native vegetation had narrower trophic niches with smaller overlaps, suggesting greater specialization. Pasture sites had greater ranges of resources exploited, indicating higher trophic diversity than sites with natural cover and sugar cane plantation. We conclude that agricultural land uses appears to alter the food base and shift macroinvertebrate assemblages towards more generalist feeding behaviors and greater overlap of the trophic niches.

  8. Are Sick Individuals Weak Competitors? Competitive Ability of Snails Parasitized by a Gigantism-Inducing Trematode

    PubMed Central

    Seppälä, Otto; Karvonen, Anssi; Kuosa, Marja; Haataja, Maarit; Jokela, Jukka

    2013-01-01

    Parasitized individuals are often expected to be poor competitors because they are weakened by infections. Many trematode species, however, although extensively exploiting their mollusc hosts, also induce gigantism (increased host size) by diverting host resources towards growth instead of reproduction. In such systems, alternatively to reduced competitive ability due to negative effects of parasitism on host performance, larger size could allow more efficient resource acquisition and thus increase the relative competitive ability of host individuals. We addressed this hypothesis by testing the effect of a trematode parasite Diplostomum pseudospathaceum on the competitive ability of its snail host Lymnaea stagnalis. We experimentally examined the growth of snails kept in pairs in relation to their infection status and intensity of resource competition (i.e. food availability). We found that parasitized snails grew faster and their reproduction was reduced compared to unparasitized individuals indicating parasite-induced gigantism. However, growth of the snails was faster when competing with parasitized individuals compared to unparasitized snails indicating reduced competitive ability due to parasitism. The latter effect, however, was relatively weak suggesting that the effects of the parasite on snail physiology may partly override each other in determining competitive ability. PMID:24205383

  9. Riparian ecosystem resilience and livelihood strategies under test: lessons from Lake Chilwa in Malawi and other lakes in Africa.

    PubMed

    Kafumbata, Dalitso; Jamu, Daniel; Chiotha, Sosten

    2014-04-05

    This paper reviews the importance of African lakes and their management challenges. African inland lakes contribute significantly to food security, livelihoods and national economies through direct exploitation of fisheries, water resources for irrigation and hydropower generation. Because of these key contributions, the ecosystem services provided are under significant stress mainly owing to high demand by increasing populations, negative anthropogenic impacts on lake catchments and high levels of poverty which result in unsustainable use. Climate variability exacerbates the stress on these ecosystems. Current research findings show that the lakes cannot sustain further development activities on the scale seen over the past few decades. Millions of people are at risk of losing livelihoods through impacts on livestock and wildlife. The review further shows that the problems facing these lakes are beyond the purview of current management practices. A much better understanding of the interactions and feedbacks between different components of the lake socio-ecological systems is needed to address the complex challenges of managing these ecosystem services. This review suggests that the three small wetlands of Chad, Chilwa and Naivasha provide an opportunity for testing novel ideas that integrate sustainability of natural resource management with livelihoods in order to inform policy on how future land use and climatic variability will affect both food security and the ecosystem services associated with it.

  10. Adding the ocean to the study of seabirds: A brief history of at-sea seabird research

    USGS Publications Warehouse

    Ainley, David G.; Ribic, Christine A.; Woehler, Eric J.

    2012-01-01

    We review the history of how research directed towards marine ornithology has led to an appreciation of seabirds as highly specialized marine organisms. Beginning with R. C. Murphy (Pacific), V. C. Wynne-Edwards (Atlantic), and associates in the early 1900s, the research approach grew from an emphasis on seabird single-species ecology to an appreciation of interacting species assemblages and finally to seabirds being considered as important components of marine food webs. After a slow, drawn-out beginning, the initial main impetus for developing the field was a need to map seabird abundance and distribution tied to understanding impacts of continental shelf resource exploitation. Coalescing during the 1970s to 1980s to facilitate this line of research were 6 factors: (1) ability to identify birds at sea; (2) standardization of techniques to quantify abundance; (3) resources and techniques for mapping; (4) appreciation of how scale affects seabird relationships to hydrographic features and patchy prey; (5) development of computing power and appropriate statistics; and (6) seabird biologists becoming embedded in, as well as organizing, multidisciplinary marine research projects. Future advances in understanding the role of seabirds in marine food webs will be made by seabird biologists participating in multidisciplinary projects using grid-like surveys relative to oceanographic features in combination with instrumentation that reveals the finer details of seabird foraging behaviors.

  11. Impacts of crop insurance on water withdrawals for irrigation

    NASA Astrophysics Data System (ADS)

    Deryugina, Tatyana; Konar, Megan

    2017-12-01

    Agricultural production remains particularly vulnerable to weather fluctuations and extreme events, such as droughts, floods, and heat waves. Crop insurance is a risk management tool developed to mitigate some of this weather risk and protect farmer income in times of poor production. However, crop insurance may have unintended consequences for water resources sustainability, as the vast majority of freshwater withdrawals go to agriculture. The causal impact of crop insurance on water use in agriculture remains poorly understood. Here, we determine the empirical relationship between crop insurance and irrigation water withdrawals in the United States. Importantly, we use an instrumental variables approach to establish causality. Our methodology exploits a major policy change in the crop insurance system - the 1994 Federal Crop Insurance Reform Act - which imposed crop insurance requirements on farmers. We find that a 1% increase in insured crop acreage leads to a 0.223% increase in irrigation withdrawals, with most coming from groundwater aquifers. We identify farmers growing more groundwater-fed cotton as an important mechanism contributing to increased withdrawals. A 1% increase in insured crop acreage leads to a 0.624% increase in cotton acreage, or 95,602 acres. These results demonstrate that crop insurance causally leads to more irrigation withdrawals. More broadly, this work underscores the importance of determining causality in the water-food nexus as we endeavor to achieve global food security and water resources sustainability.

  12. Colour cues for leaf food selection by long-tailed macaques (Macaca fascicularis) with a new suggestion for the evolution of trichromatic colour vision.

    PubMed

    Lucas, P W; Darvell, B W; Lee, P K; Yuen, T D; Choong, M F

    1998-01-01

    Leaf colour, size and toughness were investigated in five plant species important in the diet of Macaca fascicularis in Singapore. Leaf colour and size were examined as potential visual cues for food selection, whereas toughness mirrored fibre content, the inverse of food quality. As leaves matured, they changed colour and toughened. Leaf lightness and yellowness were strongly negatively correlated with toughness, but variation in both the red-green axis of the CIE Lab colour space and leaf size were not. Leaves selected as food by the macaques were distinguished by being very light, yellow to slightly green. Some leaves were dappled with red. The literature suggests that these leaves are relatively rich in protein without being tough and therefore would be sought after by primates. We argue that leaf colour is an important indicator of the nutritive value of leaves. Trichromatic vision is an important advantage in finding those palatable leaves that are dappled red. These would appear dark to dichromatic primates and be deceptive by making leaves look older (lower in quality) than they actually are. This would decrease the perceived window of feeding opportunity for such primates who would be at a disadvantage in trying to find these leaves. It is possible that trichromatic vision in catarrhine primates may have originally evolved for the detection of red coloration in the leaves of shade-tolerant tropical plants, enabling the better exploitation of a food resource.

  13. Determinants of food resource assimilation by stream insects along a tropical elevation gradient.

    PubMed

    Atkinson, Carla L; Encalada, Andrea C; Rugenski, Amanda T; Thomas, Steve A; Landeira-Dabarca, Andrea; Poff, N LeRoy; Flecker, Alexander S

    2018-04-26

    Food resource availability varies along gradients of elevation where riparian vegetative cover exerts control on the relative availability of allochthonous and autochthonous resources in streams. Still, little is known about how elevation gradients can alter the availability and quality of resources and how stream food webs respond. We sampled habitat characteristics, stable isotope signatures (δ 13 C, δ 15 N, δ 2 Η) and the carbon, nitrogen and phosphorus composition of basal food resources and insects in 11 streams of similar size along an elevation gradient from 1260 to 4045 m on the northeastern slope of the Ecuadorian Andean-Amazon region. Algal-based (autochthonous) food resources primarily supported insects occurring at higher elevations, but at low elevations there was a shift to greater allochthony, corresponding with lower light availability and reduced epilithon resource abundance. Additionally, percent phosphorus (%P) of both autochthonous and allochthonous food resources and of body tissue for some abundant insect taxa (stonefly Anacroneuria and mayfly Andesiops) declined with increasing elevation, despite the greater autochthony at high elevation. Allochthonous food resources were always a lower quality food resource, as indicated by higher C:N, N:P, and lower %P, across elevation in comparison to autochthonous resources, but autochthonous resources had higher %P than allochthonous resources across all elevations and comprised a greater portion of high-elevation insect resource assimilation. Aquatic insects may be able to compensate for the lower quality of both resource types at high elevations through altered body stoichiometry, even though higher quality autochthonous-based foods are in high abundance at high elevations.

  14. Social learning of floral odours inside the honeybee hive.

    PubMed

    Farina, Walter M; Grüter, Christoph; Díaz, Paula C

    2005-09-22

    A honeybee hive serves as an information centre in which communication among bees allows the colony to exploit the most profitable resources in a continuously changing environment. The best-studied communication behaviour in this context is the waggle dance performed by returning foragers, which encodes information about the distance and direction to the food source. It has been suggested that another information cue, floral scents transferred within the hive, is also important for recruitment to food sources, as bee recruits are more strongly attracted to odours previously brought back by foragers in both honeybees and bumble-bees. These observations suggested that honeybees learn the odour from successful foragers before leaving the hive. However, this has never been shown directly and the mechanisms and properties of the learning process remain obscure. We tested the learning and memory of recruited bees in the laboratory using the proboscis extension response (PER) paradigm, and show that recruits indeed learn the nectar odours brought back by foragers by associative learning and retrieve this memory in the PER paradigm. The associative nature of this learning reveals that information was gained during mouth-to-mouth contacts among bees (trophallaxis). Results further suggest that the information is transferred to long-term memory. Associative learning of food odours in a social context may help recruits to find a particular food source faster.

  15. New nutritional composition data on selected traditional foods consumed in Black Sea Area countries.

    PubMed

    Costa, Helena S; Albuquerque, Tânia G; Sanches-Silva, Ana; Vasilopoulou, Effie; Trichopoulou, Antonia; D'Antuono, L Filippo; Alexieva, Iordanka; Boyko, Nadiya; Costea, Carmen; Fedosova, Katerina; Hayran, Osman; Karpenko, Dmitry; Kilasonia, Zaza; Finglas, Paul

    2013-11-01

    Traditional foods are an important part of the culture, history, identity and heritage of a region or country and are key elements in dietary patterns. In most countries there is limited information on the nutritional composition of such foods and therefore there is a need to investigate, register and promote traditional foods. One of the aims within the 'Sustainable exploitation of bioactive components from the Black Sea Area traditional foods' (BaSeFood) project is to generate for the first time new data on the nutritional composition of traditional foods from six Black Sea Area countries to promote their sustainable development and exploitation. Thirty-three traditional foods were analysed in an accredited laboratory to determine their nutritional composition, and the data were fully documented. The nutrient content varied widely because of the nature and variety of the analysed foods. The energy content ranged between 4 kcal per 100 g for kvass southern and 900 kcal per 100 g for mustard oil, with the exception of the analysed teas, which did not contribute to energy intake. The use of a common methodology for the study of traditional foods will enable countries to further investigate these foods. Moreover, a new nutritional knowledge base of traditional foods from Black Sea Area countries will contribute to promote local biodiversity and sustainable diets by maintaining healthy dietary patterns within local cultures. © 2013 Society of Chemical Industry.

  16. Language and Nutrition (Mis)Information: Food Labels, FDA Policies and Meaning

    ERIC Educational Resources Information Center

    Taylor, Christy Marie

    2013-01-01

    In this dissertation, I address the ways in which food manufacturers can exploit the often vague and ambiguous nature of FDA policies concerning language and images used on food labels. Employing qualitative analysis methods (Strauss, 1987; Denzin and Lincoln, 2003; Mackey and Gass, 2005) that drew upon critical discourse analysis (Fairclough,…

  17. The role of environmental biotechnology in exploring, exploiting, monitoring, preserving, protecting and decontaminating the marine environment.

    PubMed

    Kalogerakis, Nicolas; Arff, Johanne; Banat, Ibrahim M; Broch, Ole Jacob; Daffonchio, Daniele; Edvardsen, Torgeir; Eguiraun, Harkaitz; Giuliano, Laura; Handå, Aleksander; López-de-Ipiña, Karmele; Marigomez, Ionan; Martinez, Iciar; Øie, Gunvor; Rojo, Fernando; Skjermo, Jorunn; Zanaroli, Giulio; Fava, Fabio

    2015-01-25

    In light of the Marine Strategy Framework Directive (MSFD) and the EU Thematic Strategy on the Sustainable Use of Natural Resources, environmental biotechnology could make significant contributions in the exploitation of marine resources and addressing key marine environmental problems. In this paper 14 propositions are presented focusing on (i) the contamination of the marine environment, and more particularly how to optimize the use of biotechnology-related tools and strategies for predicting and monitoring contamination and developing mitigation measures; (ii) the exploitation of the marine biological and genetic resources to progress with the sustainable, eco-compatible use of the maritime space (issues are very diversified and include, for example, waste treatment and recycling, anti-biofouling agents; bio-plastics); (iii) environmental/marine biotechnology as a driver for a sustainable economic growth. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. The impact of personal resources and their goal relevance on satisfaction with food-related life among the elderly.

    PubMed

    Dean, Moira; Grunert, Klaus G; Raats, Monique M; Nielsen, Niels Asger; Lumbers, Margaret

    2008-01-01

    The study explored how actual resources, perceived levels of different types of resources and goal relevance of these resources affect older people's satisfaction with food-related life using a survey in eight European countries, where 3291 participants above 65 years of age and living in their own homes took part. Satisfaction with food-related life was measured using Satisfaction With Food-related Life (SWFL) scale developed by Grunert, Raats, Dean, Nielsen, Lumbers and The Food in Later Life Team. [(2007). A measure of satisfaction with food-related life. Appetite, 49, 486-493]. Results showed that older people rated the resources that they believed to have plentiful of as being highly relevant to achieve their goals. The individuals who rated the relevance and their level of different resources as high were also more satisfied with their food-related quality of life. Further, satisfaction with food-related life, as was expected, was predicted by income, health measures and living circumstances. However, the study also showed that perceived levels of other resources such as support of family and friends, food knowledge, storage facilities also added to the individuals' satisfaction with food-related life. In addition, the congruence between perceived level and relevance of a resource was also shown to add to people's satisfaction with food-related life, implying that older people's satisfaction with food-related life depends not only on the level of resources they think they have but also on their goals and how important they think these resources are to achieving their goals.

  19. Fight Bac! | Partnership for Food Safety Education

    Science.gov Websites

    Games & Activities School Lunches Free Resources Be Food Safe Resources Brand Assets Brochures & Spanish Free Resources For Consumers, Retailers and Educators The Four Core Practices Food Safety Basics workers and parents Free Resources The Core Four Food Poisoning Child Care Training schoolchildren Hands

  20. Reproductive strategies of northern geese: Why wait?

    USGS Publications Warehouse

    Ely, Craig R.; Bollinger, K.S.; Densmore, R.V.; Rothe, T.C.; Petrula, M.J.; Takekawa, John Y.; Orthmeyer, D.L.

    2007-01-01

    Migration and reproductive strategies in waterbirds are tightly linked, with timing of arrival and onset of nesting having important consequences for reproductive success. Whether migratory waterbirds are capital or income breeders is predicated by their spring migration schedule, how long they are on breeding areas before nesting, and how adapted they are to exploiting early spring foods at northern breeding areas. However, for most species, we know little about individual migration schedules, arrival times, and duration of residence on breeding areas before nesting. To document these relationships in a northern nesting goose, we radiotracked winter-marked Tule Greater White-fronted Geese (Anser albifrons elgasi; hereafter “Tule Geese”; n = 116) from the time of their arrival in Alaska through nesting. Tule Geese arrived on coastal feeding areas in mid-April and moved to nesting locations a week later. They initiated nests 15 days (range: 6–24 days) after arrival, a period roughly equivalent to the duration of rapid follicle growth. Tule Geese that arrived the earliest were more likely to nest than geese that arrived later; early arrivals also spent more time on the breeding grounds and nested earlier than geese that arrived later. The length of the prenesting period was comparable to that of other populations of this species, but longer than for goose species that initiate rapid follicle growth before arrival on the breeding grounds. We suggest that Tule Geese nesting in more temperate climates are more likely to delay breeding to exploit local food resources than Arctic-nesting species that may be constrained by short growing seasons.

  1. An energy atlas of five Central American countries. Un atlas energetico de cinco paises Centroamericanos (in EN;SP)

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

    Trocki, L.; Newman, C.K.; Gurule, F.

    1988-08-01

    In a series of maps and figures, this atlas summarizes what is known about the energy resources and how these resources and oil imports supply the energy needs of five Central American countries: Guatemala, El Salvador, Honduras, Costa Rica, and Panama. The main exploited energy resources are firewood, hydroelectric energy, bagasse from sugar cane residues, and geothermal energy. Limited oil exploration in the region has uncovered modest oil resources only in Guatemala. Peat and small coal deposits are also known to exist but are not presently being exploited. After the description of energy resources, this atlas describes energy supply andmore » demand patterns in each country. It concludes with a description of socioeconomic data that strongly affect energy demand. 4 refs.« less

  2. Managing mangroves with benthic biodiversity in mind: Moving beyond roving banditry

    NASA Astrophysics Data System (ADS)

    Ellison, Aaron M.

    2008-02-01

    This review addresses mangrove management activities in the broader context of the diversity of the mangrove benthos. Goals for mangrove ecosystem management include silviculture, aquaculture, or 'ecosystem services' such as coastal protection. Silvicultural management of mangroves generally neglects the benthos, although benthic invertebrates may affect tree establishment and growth, and community composition of benthic invertebrates may be a reliable indicator of the state of managed mangrove forests. Similarly, mangrove aquaculture focuses on particular species with little attention paid either to impacts on other trophic levels or to feedbacks with the trees. Exploitation of mangrove-associated prawns, crabs, and molluscs has a total economic value > US $4 billion per year. These aquaculture operations still rely on wild-collected stock; world-wide patterns of exploitation fit the well-known process of 'roving banditry', where mobile agents move from location to location, rapidly exploiting and depleting local resources before moving on to other, as-yet unprotected grounds. Collection of brood stock and fishing for other external inputs required by aquaculture (e.g., 'trash fish') removes intermediate trophic levels from marine food webs, may destabilize them, and lead to secondary extinctions of higher-order predators. Increased attention being paid to the role of mangroves in coastal protection following the 2004 Indian Ocean tsunami provides an opportunity to reassess the relative merits of management focused on short-term economic gains. Managing for ecosystem services may ultimately preserve benthic biodiversity in mangrove ecosystems.

  3. Specialty food safety concerns and multilingual resource needs: an online survey of public health inspectors.

    PubMed

    Pham, Mai T; Jones, Andria Q; Sargeant, Jan M; Marshall, Barbara J; Dewey, Catherine E

    2010-12-01

    The province of Ontario, Canada, has a highly diverse and multicultural population. Specialty foods (i.e., foods from different cultures) are becoming increasingly available at retail food outlets and foods service establishments across the province; as a result, public health inspectors (PHIs) are increasingly required to assess the safety of foods with which they may be unfamiliar. The aim of this study was to investigate the concerns, perceptions, and self-identified needs of PHIs in Ontario with regard to specialty foods and food safety information resources in languages other than English. A cross-sectional online survey of 239 PHIs was conducted between April and June 2009. The study found that while some food safety information resources were available in languages other than English, fewer than 25% of respondents (56/239) were satisfied with the current availability of these resources. With regard to specialty foods, 60% of respondents (143/239) reported at least one specialty food with which they were not confident about their current food safety knowledge, and 64% of respondents (153/239) reported at least one specialty food with which they were dissatisfied with the current availability of food safety information. Therefore, the development of additional food safety information resources for specialty foods, and food safety resources in additional languages may provide enhanced support to PHIs involved in protecting and promoting a safe food supply.

  4. Exploiting Nutritional Value of Staple Foods in the World’s Semi-Arid Areas: Risks, Benefits, Challenges and Opportunities of Sorghum

    PubMed Central

    Proietti, Ilaria; Frazzoli, Chiara; Mantovani, Alberto

    2015-01-01

    Sorghum (Sorghum bicolor (L.) Moench) is a drought-resistant crop and an important food resource in terms of nutritional as well as social-economic values, especially in semi-arid environments. Cultivar selection and processing methods have been observed to impact on composition and functional and nutritional value of sorghum. Amino acid imbalance, cyanogenic glycosides, endogenous anti-nutrients, mycotoxins and toxic elements are among factors impairing its nutritional value. This paper reviews possible approaches (varieties selection, production practices, cooking processes) to improve the benefits-to-risks balance of sorghum meal, to mitigate the risk of deficiencies and/or imbalances and to improve effects on human nutrition. Opportunity for avoiding dietary diversification in high sorghum consumers is also discussed, e.g., tryptophan and niacin deficits potentially related to pellagra, or unavailability of proteins and divalent cations (e.g., Fe, Zn) due to the antinutrient activity of phytic acid and tannins. As potential candidate for production investments, the role of sorghum in preserving biological diversity is also considered. PMID:27417755

  5. Neurobiological Basis of Individual Variation in Stimulus-Reward Learning.

    PubMed

    Flagel, Shelly B; Robinson, Terry E

    2017-02-01

    Cues in the environment can guide behavior in adaptive ways, leading one towards valuable resources such as food, water, or a potential mate. However, cues in the environment may also serve as powerful motivators that lead to maladaptive patterns of behavior, such as addiction. Importantly, and central to this article, there is considerable individual variation in the extent to which reward cues gain motivational control over behavior. Here we describe an animal model that captures this individual variation, allowing us to better understand the psychological and neurobiological processes that contribute to cue-evoked behaviors. When a discrete cue is paired with a food reward in a Pavlovian manner it acquires greater control over motivated behavior in some rats ("sign-trackers, STs) than in others ("goal-trackers", GTs). We review studies that have exploited this animal model to parse the neurobiological mechanisms involved in learning associations between stimuli vs. those involved in attributing incentive salience to those same stimuli. The latter seems to be dependent on dopamine and subcortical circuits, whereas the former may engage more cortical "top-down" mechanisms.

  6. Exploiting Nutritional Value of Staple Foods in the World's Semi-Arid Areas: Risks, Benefits, Challenges and Opportunities of Sorghum.

    PubMed

    Proietti, Ilaria; Frazzoli, Chiara; Mantovani, Alberto

    2015-03-30

    Sorghum (Sorghum bicolor (L.) Moench) is a drought-resistant crop and an important food resource in terms of nutritional as well as social-economic values, especially in semi-arid environments. Cultivar selection and processing methods have been observed to impact on composition and functional and nutritional value of sorghum. Amino acid imbalance, cyanogenic glycosides, endogenous anti-nutrients, mycotoxins and toxic elements are among factors impairing its nutritional value. This paper reviews possible approaches (varieties selection, production practices, cooking processes) to improve the benefits-to-risks balance of sorghum meal, to mitigate the risk of deficiencies and/or imbalances and to improve effects on human nutrition. Opportunity for avoiding dietary diversification in high sorghum consumers is also discussed, e.g., tryptophan and niacin deficits potentially related to pellagra, or unavailability of proteins and divalent cations (e.g., Fe, Zn) due to the antinutrient activity of phytic acid and tannins. As potential candidate for production investments, the role of sorghum in preserving biological diversity is also considered.

  7. 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. © 2013 John Wiley & Sons Ltd.

  8. Application of territorial GIS to study of natural environment for regions under mining exploitation

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

    Kirsanov, A.

    1996-07-01

    Mineral resources exploitation becomes one of the leading factors of technogenic impact to natural environment. The processes accompanying exploitation lead to changes of geological/geomorphological, engineering/geological, hydrogeological, geochemical and landscape conditions over the large territories surrounded mining exploitation districts. The types of environmental changes and disturbances are stipulated by several reasons such as kind of exploited resources (ore, petroleum, gas, coal, peat, building materials etc.); the ways of extraction (opened by quarry or closed by mine); natural zone (tundra, taiga, steppe, desert etc.). Expressive revelation and control of these environmental changes is impossible without wide using and analysis of various typesmore » and different times materials of airborne and satellite surveys (MASS). They are the basis of system approach to environmental study because of image is the decreased spatial model of territory. For integrated estimation of natural resources and perspectives of its economical profit using, as well as examination of influence of extraction objects to natural environment necessary to involve different data. Only territorial GIS permits to solve the tasks of collection, keeping, processing and analysis of this data as well as to conduct modelling of situations and presentation of information necessary to accept the decision. The core of GIS is the Data base which consists of initial remote sensing and cartographic data allow in completely obtain various information providing of full value and objectivity of investigations.« less

  9. Parrots as key multilinkers in ecosystem structure and functioning.

    PubMed

    Blanco, Guillermo; Hiraldo, Fernando; Rojas, Abraham; Dénes, Francisco V; Tella, José L

    2015-09-01

    Mutually enhancing organisms can become reciprocal determinants of their distribution, abundance, and demography and thus influence ecosystem structure and dynamics. In addition to the prevailing view of parrots (Psittaciformes) as plant antagonists, we assessed whether they can act as plant mutualists in the dry tropical forest of the Bolivian inter-Andean valleys, an ecosystem particularly poor in vertebrate frugivores other than parrots (nine species). We hypothesised that if interactions between parrots and their food plants evolved as primarily or facultatively mutualistic, selection should have acted to maximize the strength of their interactions by increasing the amount and variety of resources and services involved in particular pairwise and community-wide interaction contexts. Food plants showed different growth habits across a wide phylogenetic spectrum, implying that parrots behave as super-generalists exploiting resources differing in phenology, type, biomass, and rewards from a high diversity of plants (113 species from 38 families). Through their feeding activities, parrots provided multiple services acting as genetic linkers, seed facilitators for secondary dispersers, and plant protectors, and therefore can be considered key mutualists with a pervasive impact on plant assemblages. The number of complementary and redundant mutualistic functions provided by parrots to each plant species was positively related to the number of different kinds of food extracted from them. These mutually enhancing interactions were reflected in species-level properties (e.g., biomass or dominance) of both partners, as a likely consequence of the temporal convergence of eco-(co)evolutionary dynamics shaping the ongoing structure and organization of the ecosystem. A full assessment of the, thus far largely overlooked, parrot-plant mutualisms and other ecological linkages could change the current perception of the role of parrots in the structure, organization, and functioning of ecosystems.

  10. Mating System and Sexual Selection in the Scorpionfly Panorpa vulgaris (Mecoptera: Panorpidae)

    NASA Astrophysics Data System (ADS)

    Sauer, Klaus Peter; Lubjuhn, Thomas; Sindern, Jörn; Kullmann, Harald; Kurtz, Joachim; Epplen, Conny; Epplen, Jörg Thomas

    1998-05-01

    has become a model insect for testing theories of sexual selection. This contribution summarizes that which has been learned in recent years and presents new data that clearly show that the mating system of P. vulgaris is not simply a resource-defense polygyny, as has previously been thought. In P. vulgaris neither the pattern in food exploitation nor the ratio of variance in the lifetime reproductive success of the two sexes is in accordance with that expected in resource defense polygynous mating systems. Lifetime mating duration is the most important proximate determinant of male fitness. Males employing alternative mating tactics obtain copulations of varying duration in relation to the following sequence: saliva secretion 1 food offering 1 no gift. The number of salivary masses which males provide to females during their lifetime is significantly correlated with the lifetime condition index. The condition index depends on the fighting prowess of males and their ability to find food items. Thus saliva secretion of Panorpa is considered a Zahavian handicap, which can serve as an honest quality indicator used by mating females. Our results confirm four main predictions of the indicator model of the theory of sexual selection: (a) the indicator signals high ecological quality of its bearer, (b) the indicator value increases with phenotypic quality, (c) the indicator value is positively correlated with the genetic quality affecting offspring fitness in a natural selection context, and (d) the quality indicator is more costly for low- than for high-quality individuals. The evolutionary consequences of the mating pattern and the sperm competition mechanism in P. vulgaris are discussed in the context the way in which sexual selection creates and maintains sperm mixing and the evolution of a promiscuous mating system.

  11. Addressing challenges to human health in the Anthropocene epoch-an overview of the findings of the Rockefeller/Lancet Commission on Planetary Health.

    PubMed

    Haines, Andy

    The report of the Rockefeller Foundation/Lancet Commission on Planetary Health described how human health directly depends upon the environment. It takes a broad perspective not only acknowledging climate change as the most important global environmental threat to health but also recognizing other impacts, including dramatic loss of tropical forests, land degradation, loss of biodiversity, declining freshwater resources, ocean acidification, and over-exploitation of fisheries. All pose challenges to human health gains, leading to the concept of planetary health-that the human condition is tied to natural systems. The Planetary Health Commission report highlights several major concerns arising from environmental change including impacts on food availability and quality, increases in natural disasters and population displacement, and newly emerging diseases, e.g. from zoonotic infections. Three challenges emerge from the report: the first is imagination, or conceptual challenges-better metrics are needed to assess human progress within the context of environmental change; the second is a lack of relevant knowledge, requiring more research on the inter-linkages between environmental change and health and on the effectiveness of potential solutions; and the third is implementation of solutions, ensuring that the science is translated into policy and practice. There are many opportunities to promote planetary health including developing sustainable and healthy cities, encouraging more resilient health systems and disaster preparedness, reducing food waste, preserving ecosystems, and redirecting harmful subsidies in food, agriculture, fishery and energy sectors. Many current trends are driven by inequitable, inefficient, and unsustainable patterns of resource consumption and technological development, coupled with population growth, but solutions lie within reach. Prosperity must be redefined as an enhancement of the quality of life and the delivery of improved health for all, together with respect for natural systems.

  12. Synergies between climate and management for Atlantic cod fisheries at high latitudes

    PubMed Central

    Kjesbu, Olav Sigurd; Bogstad, Bjarte; Devine, Jennifer A.; Gjøsæter, Harald; Howell, Daniel; Ingvaldsen, Randi B.; Nash, Richard D. M.; Skjæraasen, Jon Egil

    2014-01-01

    The widespread depletion of commercially exploited marine living resources is often seen as a general failure of management and results in criticism of contemporary management procedures. When populations show dramatic and positive changes in population size, this invariably leads to questions about whether favorable climatic conditions or good management (or both) were responsible. The Barents Sea cod (Gadus morhua) stock has recently increased markedly and the spawning stock biomass is now at an unprecedented high. We identify the crucial social and environmental factors that made this unique growth possible. The relationship between vital rates of Barents Sea cod stock productivity (recruitment, growth, and mortality) and environment is investigated, followed by simulations of population size under different management scenarios. We show that the recent sustained reduction in fishing mortality, facilitated by the implementation of a “harvest control rule,” was essential to the increase in population size. Simulations show that a drastic reduction in fishing mortality has resulted in a doubling of the total population biomass compared with that expected under the former management regime. However, management alone was not solely responsible. We document that prevailing climate, operating through several mechanistic links, positively reinforced management actions. Heightened temperature resulted in an increase in the extent of the suitable feeding area for Barents Sea cod, likely offering a release from density-dependent effects (for example, food competition and cannibalism) through prolonged overlap with prey and improved adult stock productivity. Management and climate may thus interact to give a positive outlook for exploited high-latitude marine resources. PMID:24550465

  13. Synergies between climate and management for Atlantic cod fisheries at high latitudes.

    PubMed

    Kjesbu, Olav Sigurd; Bogstad, Bjarte; Devine, Jennifer A; Gjøsæter, Harald; Howell, Daniel; Ingvaldsen, Randi B; Nash, Richard D M; Skjæraasen, Jon Egil

    2014-03-04

    The widespread depletion of commercially exploited marine living resources is often seen as a general failure of management and results in criticism of contemporary management procedures. When populations show dramatic and positive changes in population size, this invariably leads to questions about whether favorable climatic conditions or good management (or both) were responsible. The Barents Sea cod (Gadus morhua) stock has recently increased markedly and the spawning stock biomass is now at an unprecedented high. We identify the crucial social and environmental factors that made this unique growth possible. The relationship between vital rates of Barents Sea cod stock productivity (recruitment, growth, and mortality) and environment is investigated, followed by simulations of population size under different management scenarios. We show that the recent sustained reduction in fishing mortality, facilitated by the implementation of a "harvest control rule," was essential to the increase in population size. Simulations show that a drastic reduction in fishing mortality has resulted in a doubling of the total population biomass compared with that expected under the former management regime. However, management alone was not solely responsible. We document that prevailing climate, operating through several mechanistic links, positively reinforced management actions. Heightened temperature resulted in an increase in the extent of the suitable feeding area for Barents Sea cod, likely offering a release from density-dependent effects (for example, food competition and cannibalism) through prolonged overlap with prey and improved adult stock productivity. Management and climate may thus interact to give a positive outlook for exploited high-latitude marine resources.

  14. Preservation and fermentation: past, present and future.

    PubMed

    Ross, R Paul; Morgan, S; Hill, C

    2002-11-15

    Preservation of food and beverages resulting from fermentation has been an effective form of extending the shelf-life of foods for millennia. Traditionally, foods were preserved through naturally occurring fermentations, however, modern large scale production generally now exploits the use of defined strain starter systems to ensure consistency and quality in the final product. This review will mainly focus on the use of lactic acid bacteria (LAB) for food improvement, given their extensive application in a wide range of fermented foods. These microorganisms can produce a wide variety of antagonistic primary and secondary metabolites including organic acids, diacetyl, CO2 and even antibiotics such as reuterocyclin produced by Lactobacillus reuteri. In addition, members of the group can also produce a wide range of bacteriocins, some of which have activity against food pathogens such as Listeria monocytogenes and Clostridium botulinum. Indeed, the bacteriocin nisin has been used as an effective biopreservative in some dairy products for decades, while a number of more recently discovered bacteriocins, such as lacticin 3147, demonstrate increasing potential in a number of food applications. Both of these lactococcal bacteriocins belong to the lantibiotic family of posttranslationally modified bacteriocins that contain lanthionine, beta-methyllanthionine and dehydrated amino acids. The exploitation of such naturally produced antagonists holds tremendous potential for extension of shelf-life and improvement of safety of a variety of foods.

  15. A Historical Perspective on Local Environmental Movements in Japan: Lessons for the Transdisciplinary Approach on Water Resource Governance

    NASA Astrophysics Data System (ADS)

    Oh, T.

    2014-12-01

    Typical studies on natural resources from a social science perspective tend to choose one type of resource—water, for example— and ask what factors contribute to the sustainable use or wasteful exploitation of that resource. However, climate change and economic development, which are causing increased pressure on local resources and presenting communities with increased levels of tradeoffs and potential conflicts, force us to consider the trade-offs between options for using a particular resource. Therefore, the transdisciplinary approach that accurately captures the advantages and disadvantages of various possible resource uses is particularly important in the complex social-ecological systems, where concerns about inequality with respect to resource use and access have become unavoidable. Needless to say, resource management and policy require sound scientific understanding of the complex interconnections between nature and society, however, in contrast to typical international discussions, I discuss Japan not as an "advanced" case where various dilemmas have been successfully addressed by the government through the optimal use of technology, but rather as a nation seeing an emerging trend that is based on a awareness of the connections between local resources and the environment. Furthermore, from a historical viewpoint, the nexus of local resources is not a brand-new idea in the experience of environmental governance in Japan. There exist the local environment movements, which emphasized the interconnection of local resources and succeeded in urging the governmental action and policymaking. For this reason, local movements and local knowledge for the resource governance warrant attention. This study focuses on the historical cases relevant to water resource management including groundwater, and considers the contexts and conditions to holistically address local resource problems, paying particular attention to interactions between science and society. I will argue the research design to enhance the holistic view of local stakeholders on local resources as the key to effective transdisciplinary approach through the on-going research project focusing on the water-energy-food nexus.

  16. Another unique river: a consideration of some of the characteristics of the trunk tributaries of the Nile River in northwestern Ethiopia in relationship to their aquatic food resources.

    PubMed

    Kappelman, John; Tewabe, Dereje; Todd, Lawrence; Feseha, Mulugeta; Kay, Marvin; Kocurek, Gary; Nachman, Brett; Tabor, Neil; Yadeta, Meklit

    2014-12-01

    Aquatic food resources are important components of many modern human hunter-gatherer diets and yet evidence attesting to the widespread exploitation of this food type appears rather late in the archaeological record. While there are times when, for example, the capture of fish and shellfish requires sophisticated technology, there are other cases when the exact ecological attributes of an individual species and the particulars of its environment make it possible for these foods to be incorporated into the human diet with little or no tool use and only a minimal time investment. In order to better understand the full set of variables that are considered in these sorts of foraging decisions, it is necessary to detail the attributes of each particular aquatic environment. We discuss here some of the characteristics of the trunk tributaries of the Nile and Blue Rivers in the Horn of Africa. Unlike typical perennial rivers, these 'temporary' rivers flow only during a brief but intense wet season; during the much longer dry season, the rivers are reduced to a series of increasingly disconnected waterholes, and the abundant and diverse fish and mollusk populations are trapped in ever smaller evaporating pools. The local human population today utilizes a number of diverse capture methods that range from simple to complex, and vary according to the size and depth of the waterhole and the time of the year. When we view the particular characteristics of an individual river system, we find that each river is 'unique' in its individual attributes. The Horn of Africa is believed to be along the route that modern humans followed on their migration out of Africa, and it is likely that the riverine-based foraging behaviors of these populations accompanied our species on its movement into the rest of the Old World. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Food Insecurity and Food Resource Utilization in an Urban Immigrant Community.

    PubMed

    Greenwald, Howard P; Zajfen, Vanessa

    2017-02-01

    Risk and prevalence of food insecurity and use of food security resources are important but incompletely understood factors in immigrant health. Key informant interviews and a survey (N = 809) of housing units were conducted in a San Diego, California neighborhood with a high proportion of immigrant and low income families. The difference in food insecurity between immigrant and non-immigrant households was non-significant (20.1 vs. 15.7 %, p = n.s.), though immigrant families were more likely to use food security resources such as SNAP (32.7 vs. 22.9 %, p < .01) and food pantries (28.2 vs. 19.7 %, p < .001). Among immigrants, neither national origin nor years in the United States predicted food insecurity or use of most food security resources. In immigrant families, food insecurity often remains a challenge long after immigration, suggesting a potentially increasing need for food security resources as immigration into the United States continues.

  18. Assessment of wild leafy vegetables traditionally consumed by the ethnic communities of Manipur, northeast India.

    PubMed

    Konsam, Surjata; Thongam, Biseshwori; Handique, Arun Kumar

    2016-01-29

    The NE region of India falls in the global hotspot of biodiversity. Wild edible plants (WEPs) are widely consumed in the daily diet of the local people. WEPs are critical for the sustenance of ethnic communities and also as a source of income. However, WEPs received a little attention in research activities, economic development, biodiversity conservation and sustainable management. Many are largely ignored and remained unexplored. With a view of reducing the gap in traditional knowledge and tapping the hidden potential resources for proper utilization, exploitation, and sustainable management of WEPs are crucial. Surveys were conducted at 20 major markets in all districts of Manipur throughout different seasons from August 2012 to March 2014. A total of 154 avid plant collectors and sellers were interviewed using semi-structured questionnaire, formal, informal and extensive interactions to gather detailed information about these species. An integrated assessment of 68 wild leafy vegetables was also carried out to prioritize them for proper exploitation, conservation, and sustainable management. A total of 68 wild edible vegetables belonging to 42 families were documented which are being used by indigenous communities for nutritive and therapeutic purposes. Of these species, 54 are perennial (79 %) while others are annual (19 %). Herbaceous plants make up the highest proportion of edible plants. Leaves are dominant edible part followed by shoot and stem, and most are consumed through cooked food. Further, 57 species (84 %) are commonly available, and 11 (16 %) are rare. According to integrated assessment, 2 species have highest integrated value, 26 species have high value, 31 species have general value and 9 species are of low value. The majority of the species have a high or general value. Manipur has rich wild vegetable resources. However, many of them are seldom collected or cultivated given their importance in sustaining and diversifying diet. A comprehensive assessment indicated that majority of these plants have high value. Priority species require further research into their nutritional components to understand the potential as a source of future food and nutritional security. They should be promoted for integration into the agricultural system and income generation for local sustenance.

  19. Vertebrates used for medicinal purposes by members of the Nyishi and Galo tribes in Arunachal Pradesh (North-East India)

    PubMed Central

    2011-01-01

    Arunachal Pradesh, the easternmost part of India, is endowed with diverse natural resources and inhabited by a variety of ethnic groups that have developed skills to exploit the biotic resources of the region for food and medicines. Information on animals and animal parts as components of folk remedies used by local healers and village headmen of the Nyishi and Galo tribes in their respective West Siang and Subansiri districts were obtained through interviews and structured questionnaires. Of a total of 36 vertebrate species used in treatments of ailments and diseases, mammals comprised 50%; they were followed by birds (22%), fishes (17%), reptiles (8%) and amphibians (3%). Approximately 20 common complaints of humans as well as foot and mouth disease of cattle were targets of zootherapies. Most commonly treated were fevers, body aches and pains, tuberculosis, malaria, wounds and burns, typhoid, smallpox, dysentery and diarrhoea, jaundice, and early pregnancy pains. Very few domestic animal species (e.g., goat and cattle) were used zootherapeutically. More frequently it was wild animals, including endangered or protective species like hornbill, pangolin, clouded leopard, tiger, bear, and wolf, whose various parts were either used in folk remedies or as food. Some of the animal-based traditional medicines or animal parts were sold at local markets, where they had to compete with modern, western pharmaceuticals. To record, document, analyze and test the animal-derived local medicines before they become replaced by western products is one challenge; to protect the already dwindling populations of certain wild animal species used as a resource for the traditional animal-derived remedies, is another. PMID:21453496

  20. Vertebrates used for medicinal purposes by members of the Nyishi and Galo tribes in Arunachal Pradesh (North-East India).

    PubMed

    Chakravorty, Jharna; Meyer-Rochow, V Benno; Ghosh, Sampat

    2011-03-31

    Arunachal Pradesh, the easternmost part of India, is endowed with diverse natural resources and inhabited by a variety of ethnic groups that have developed skills to exploit the biotic resources of the region for food and medicines. Information on animals and animal parts as components of folk remedies used by local healers and village headmen of the Nyishi and Galo tribes in their respective West Siang and Subansiri districts were obtained through interviews and structured questionnaires. Of a total of 36 vertebrate species used in treatments of ailments and diseases, mammals comprised 50%; they were followed by birds (22%), fishes (17%), reptiles (8%) and amphibians (3%). Approximately 20 common complaints of humans as well as foot and mouth disease of cattle were targets of zootherapies. Most commonly treated were fevers, body aches and pains, tuberculosis, malaria, wounds and burns, typhoid, smallpox, dysentery and diarrhoea, jaundice, and early pregnancy pains. Very few domestic animal species (e.g., goat and cattle) were used zootherapeutically. More frequently it was wild animals, including endangered or protective species like hornbill, pangolin, clouded leopard, tiger, bear, and wolf, whose various parts were either used in folk remedies or as food. Some of the animal-based traditional medicines or animal parts were sold at local markets, where they had to compete with modern, western pharmaceuticals. To record, document, analyze and test the animal-derived local medicines before they become replaced by western products is one challenge; to protect the already dwindling populations of certain wild animal species used as a resource for the traditional animal-derived remedies, is another.

  1. New insights to lateral rooting: Differential responses to heterogeneous nitrogen availability among maize root types

    PubMed Central

    Yu, Peng; White, Philip J; Li, Chunjian

    2015-01-01

    Historical domestication and the "Green revolution" have both contributed to the evolution of modern, high-performance crops. Together with increased irrigation and application of chemical fertilizers, these efforts have generated sufficient food for the growing global population. Root architecture, and in particular root branching, plays an important role in the acquisition of water and nutrients, plant performance, and crop yield. Better understanding of root growth and responses to the belowground environment could contribute to overcoming the challenges faced by agriculture today. Manipulating the abilities of crop root systems to explore and exploit the soil environment could enable plants to make the most of soil resources, increase stress tolerance and improve grain yields, while simultaneously reducing environmental degradation. In this article it is noted that the control of root branching, and the responses of root architecture to nitrate availability, differ between root types and between plant species. Since the control of root branching depends upon both plant species and root type, further work is urgently required to determine the appropriate genes to manipulate to improve resource acquisition by specific crops. PMID:26443081

  2. Proactive responses to human impacts that balance development and Atlantic salmon (Salmo salar) conservation: An integrative model

    USGS Publications Warehouse

    Wilzbach, M.A.; Mather, M. E.; Folt, C.L.; Moore, A.; Naiman, R.J.; Youngson, A.F.; McMenemy, J.

    1998-01-01

    Incorporating human impacts into conservation plans is critical to protect natural resources. Using a model that examines how anthropogenic changes might be proactively influenced to promote conservation, we argue that a denser human population does not spell inevitable doom for Atlantic salmon (Salmo salar). Humans affect the Atlantic salmon ecosystem deleteriously through landscape alteration, exploitation, external inputs, and resource competition. An intact ecosystem provides positive feedback to society by providing food, ecosystem services, and improving the quality of life. As Atlantic salmon and associated ecosystem benefits are increasingly valued by society, policies, laws, and regulations that protect salmon populations and habitats are codified into a 'control system' or institutional infrastructure. Via research that helps maintain wild salmon populations and in informing the public about the benefits of a healthy Atlantic salmon ecosystem, scientists can influence public attitudes and facilitate the implementation of environmental policies that moderate harmful anthropogenic changes. Because exchange among scientists is of paramount importance in increasing our understanding of important interrelationships between humans and fish, we recommend the establishment of an international salmon organizational for research.

  3. New insights to lateral rooting: Differential responses to heterogeneous nitrogen availability among maize root types.

    PubMed

    Yu, Peng; White, Philip J; Li, Chunjian

    2015-01-01

    Historical domestication and the "Green revolution" have both contributed to the evolution of modern, high-performance crops. Together with increased irrigation and application of chemical fertilizers, these efforts have generated sufficient food for the growing global population. Root architecture, and in particular root branching, plays an important role in the acquisition of water and nutrients, plant performance, and crop yield. Better understanding of root growth and responses to the belowground environment could contribute to overcoming the challenges faced by agriculture today. Manipulating the abilities of crop root systems to explore and exploit the soil environment could enable plants to make the most of soil resources, increase stress tolerance and improve grain yields, while simultaneously reducing environmental degradation. In this article it is noted that the control of root branching, and the responses of root architecture to nitrate availability, differ between root types and between plant species. Since the control of root branching depends upon both plant species and root type, further work is urgently required to determine the appropriate genes to manipulate to improve resource acquisition by specific crops.

  4. Exploiting short-term memory in soft body dynamics as a computational resource

    PubMed Central

    Nakajima, K.; Li, T.; Hauser, H.; Pfeifer, R.

    2014-01-01

    Soft materials are not only highly deformable, but they also possess rich and diverse body dynamics. Soft body dynamics exhibit a variety of properties, including nonlinearity, elasticity and potentially infinitely many degrees of freedom. Here, we demonstrate that such soft body dynamics can be employed to conduct certain types of computation. Using body dynamics generated from a soft silicone arm, we show that they can be exploited to emulate functions that require memory and to embed robust closed-loop control into the arm. Our results suggest that soft body dynamics have a short-term memory and can serve as a computational resource. This finding paves the way towards exploiting passive body dynamics for control of a large class of underactuated systems. PMID:25185579

  5. The interaction of cannibalism and omnivory: consequences for community dynamics.

    PubMed

    Rudolf, Volker H W

    2007-11-01

    Although cannibalism is ubiquitous in food webs and frequent in systems where a predator and its prey also share a common resource (intraguild predation, IGP), its impacts on species interactions and the dynamics and structure of communities are still poorly understood. In addition, the few existing studies on cannibalism have generally focused on cannibalism in the top-predator, ignoring that it is frequent at intermediate trophic levels. A set of structured models shows that cannibalism can completely alter the dynamics and structure of three-species IGP systems depending on the trophic position where cannibalism occurs. Contrary to the expectations of simple models, the IG predator can exploit the resources more efficiently when it is cannibalistic, enabling the predator to persist at lower resource densities than the IG prey. Cannibalism in the IG predator can also alter the effect of enrichment, preventing predator-mediated extinction of the IG prey at high productivities predicted by simple models. Cannibalism in the IG prey can reverse the effect of top-down cascades, leading to an increase in the resource with decreasing IG predator density. These predictions are consistent with current data. Overall, cannibalism promotes the coexistence of the IG predator and IG prey. These results indicate that including cannibalism in current models can overcome the discrepancy between theory and empirical data. Thus, we need to measure and account for cannibalistic interactions to reliably predict the structure and dynamics of communities.

  6. Designing and visualizing the water-energy-food nexus system

    NASA Astrophysics Data System (ADS)

    Endo, A.; Kumazawa, T.; Yamada, M.; Kato, T.

    2017-12-01

    The objective of this study is to design and visualize a water-energy-food nexus system to identify the interrelationships between water-energy-food (WEF) resources and to understand the subsequent complexity of WEF nexus systems holistically, taking an interdisciplinary approach. Object-oriented concepts and ontology engineering methods were applied according to the hypothesis that the chains of changes in linkages between water, energy, and food resources holistically affect the water-energy-food nexus system, including natural and social systems, both temporally and spatially. The water-energy-food nexus system that is developed is significant because it allows us to: 1) visualize linkages between water, energy, and food resources in social and natural systems; 2) identify tradeoffs between these resources; 3) find a way of using resources efficiently or enhancing the synergy between the utilization of different resources; and 4) aid scenario planning using economic tools. The paper also discusses future challenges for applying the developed water-energy-food nexus system in other areas.

  7. An Educational Paper on the Effect Of Even Distribution in the Use of Available Energy Resources So as to Enhance Sustainability

    NASA Astrophysics Data System (ADS)

    Njuh Elongo, A. I.

    2017-12-01

    This paper seeks to suggest a possible and proper solution to the problem of over-exploitation of a certain major energy resource up-to its point of near extinction or pass its peak value. To achieve or present this hypothesis, an experiment was done which varied the following factors which are; the available natural resources, the demand rate and hence consumption rate. The question being " Can sharing the exploitation and consumption of available resources equally, improve sustainability?. " This was investigated through a simple experiment in a farm, via the use of goats grazing on grass. The test experiment was done on one farm where the goats were fed with three different types of grass found around the area, and was fed to them simultaneously as the number of goats also were increased with time. Also, on the other farm which hosted the control experiment, the three types of grass was introduced to the feeding process only when its predecessor was almost going towards extinction. The population of the goats also was increased with time. It was found that on the first farm(test farm) , the resources (being the grass) lasted for a longer time on the farm which hosted the test experiment. So it was concluded that, certainly, the "even distribution" of the exploitation and consumption of resources leads to an increase in sustainability.

  8. Exploiting the explosion of information associated with whole genome sequencing to tackle Shiga toxin-producing Escherichia coli (STEC) in global food production systems

    USDA-ARS?s Scientific Manuscript database

    The rates of foodborne disease caused by gastrointestinal pathogens continue to be a concern in both the developed and developing worlds. The growing world population, the increasing complexity of agri-food networks and the wide range of foods now associated with STEC are potential drivers for incre...

  9. On the Water-Food Nexus: an Optimization Approach for Water and Food Security

    NASA Astrophysics Data System (ADS)

    Mortada, Sarah; Abou Najm, Majdi; Yassine, Ali; Alameddine, Ibrahim; El-Fadel, Mutasem

    2016-04-01

    Water and food security is facing increased challenges with population increase, climate and land use change, as well as resource depletion coupled with pollution and unsustainable practices. Coordinated and effective management of limited natural resources have become an imperative to meet these challenges by optimizing the usage of resources under various constraints. In this study, an optimization model is developed for optimal resource allocation towards sustainable water and food security under nutritional, socio-economic, agricultural, environmental, and natural resources constraints. The core objective of this model is to maximize the composite water-food security status by recommending an optimal water and agricultural strategy. The model balances between the healthy nutritional demand side and the constrained supply side while considering the supply chain in between. It equally ensures that the population achieves recommended nutritional guidelines and population food-preferences by quantifying an optimum agricultural and water policy through transforming optimum food demands into optimum cropping policy given the water and land footprints of each crop or agricultural product. Through this process, water and food security are optimized considering factors that include crop-food transformation (food processing), water footprints, crop yields, climate, blue and green water resources, irrigation efficiency, arable land resources, soil texture, and economic policies. The model performance regarding agricultural practices and sustainable food and water security was successfully tested and verified both at a hypothetical and pilot scale levels.

  10. Seasonal source-sink dynamics at the edge of a species' range

    USGS Publications Warehouse

    Kanda, L.L.; Fuller, T.K.; Sievert, P.R.; Kellogg, R.L.

    2009-01-01

    The roles of dispersal and population dynamics in determining species' range boundaries recently have received theoretical attention but little empirical work. Here we provide data on survival, reproduction, and movement for a Virginia opossum (Didelphis virginiana) population at a local distributional edge in central Massachusetts (USA). Most juvenile females that apparently exploited anthropogenic resources survived their first winter, whereas those using adjacent natural resources died of starvation. In spring, adult females recolonized natural areas. A life-table model suggests that a population exploiting anthropogenic resources may grow, acting as source to a geographically interlaced sink of opossums using only natural resources, and also providing emigrants for further range expansion to new human-dominated landscapes. In a geographical model, this source-sink dynamic is consistent with the local distribution identified through road-kill surveys. The Virginia opossum's exploitation of human resources likely ameliorates energetically restrictive winters and may explain both their local distribution and their northward expansion in unsuitable natural climatic regimes. Landscape heterogeneity, such as created by urbanization, may result in source-sink dynamics at highly localized scales. Differential fitness and individual dispersal movements within local populations are key to generating regional distributions, and thus species ranges, that exceed expectations. ?? 2009 by the Ecological Society of America.

  11. The Illusions and Juxtapositions of Commercial Sexual Exploitation among Youth: Identifying Effective Street-Outreach Strategies

    PubMed Central

    HOLGER-AMBROSE, BETH; LANGMADE, CHEREE; EDINBURGH, LAUREL D.; SAEWYC, ELIZABETH

    2015-01-01

    To explore sexually exploited youths’ perspectives of how street outreach workers can effectively provide outreach and connections to services, we conducted qualitative interviews with 13 female participants, ages 14–22, in a Midwestern U.S. city. Participants reported multiple types of exploitation, most first exploited by age 13, plus substance use, and recurrent homelessness. Nearly all had a pimp, and all used the internet as a venue for sexual exploitation. Participants wanted outreach workers to use “soft words” to refer to exploitation. They expressed contradictory images of their “boyfriend” pimps and their exploitation. They wanted outreach workers to “provide resources,” “be non-judgmental,” ”listen,” and “care.” Street outreach can be one way to support sexually exploited youth, but should occur in multiple settings. PMID:23590353

  12. Hunger and Satiety Mechanisms and Their Potential Exploitation in the Regulation of Food Intake.

    PubMed

    Amin, Tehmina; Mercer, Julian G

    2016-03-01

    Effective strategies to combat recent rises in obesity levels are limited. The accumulation of excess body fat results when energy intake exceeds that expended. Energy balance is controlled by hypothalamic responses, but these can be overridden by hedonic/reward brain systems. This override, combined with unprecedented availability of cheap, energy-dense, palatable foods, may partly explain the increase in overweight and obesity. The complexity of the processes that regulate feeding behaviour has driven the need for further fundamental research. Full4Health is an EU-funded project conceived to advance our understanding of hunger and satiety mechanisms. Food intake has an impact on and is also affected by the gut-brain signalling which controls hunger and appetite. This review describes selected recent research from Full4Health and how new mechanistic findings could be exploited to adapt and control our physiological responses to food, potentially providing an alternative solution to addressing the global problems related to positive energy balance.

  13. Prolonging the arctic pulse: long-term exploitation of cached eggs by arctic foxes when lemmings are scarce.

    PubMed

    Samelius, Gustaf; Alisauskas, Ray T; Hobson, Keith A; Larivière, Serge

    2007-09-01

    1. Many ecosystems are characterized by pulses of dramatically higher than normal levels of foods (pulsed resources) to which animals often respond by caching foods for future use. However, the extent to which animals use cached foods and how this varies in relation to fluctuations in other foods is poorly understood in most animals. 2. Arctic foxes Alopex lagopus (L.) cache thousands of eggs annually at large goose colonies where eggs are often superabundant during the nesting period by geese. We estimated the contribution of cached eggs to arctic fox diets in spring and autumn, when geese were not present in the study area, by comparing stable isotope ratios (delta(13)C and delta(15)N) of fox tissues with those of their foods using a multisource mixing model in Program IsoSource. 3. The contribution of cached eggs to arctic fox diets was inversely related to collared lemming Dicrostonyx groenlandicus (Traill) abundance; the contribution of cached eggs to overall fox diets increased from < 28% in years when collared lemmings were abundant to 30-74% in years when collared lemmings were scarce. 4. Further, arctic foxes used cached eggs well into the following spring (almost 1 year after eggs were acquired) - a pattern that differs from that of carnivores generally storing foods for only a few days before consumption. 5. This study showed that long-term use of eggs that were cached when geese were superabundant at the colony in summer varied with fluctuations in collared lemming abundance (a key component in arctic fox diets throughout most of their range) and suggests that cached eggs functioned as a buffer when collared lemmings were scarce.

  14. Relationships between oral morphology and feeding style in the Ungulata: a phylogenetically controlled evaluation.

    PubMed

    Pérez-Barbería, F J; Gordon, I J

    2001-05-22

    In ungulates it is argued that specialization in the consumption of a particular type of food (feeding style) is reflected in morphological adaptations of the organs involved in the selection, processing and digestion of food. We analysed the differences in size and morphology of some oral traits that have been functionally related to food-selection ability (muzzle width, incisor-arcade shape, incisor shape), prehension of food (incisor protrusion), food comminution (molar occlusal surface area, hypsodonty (high-crowned molars)) and intake rate (incisor breadth) between ungulate species with different feeding styles (browser, mixed feeder, grazer). Grazers were characterized by large-body-size species. After controlling only for body mass, we found that grazers had wider muzzles and incisors, more-protruding incisors and more-bulky and higher-crowned molars than did mixed feeders and browsers. When the analyses took into account both body mass and phylogeny, only body mass and two out of the three hypsodonty indexes used remained significantly different between feeding styles. Browsers were smaller, on average, than mixed feeders and grazers, whilst grazers and mixed feeders did not differ in size. Also, browsers had shorter and less-bulky molars than did mixed feeders and grazers; the latter two feeding styles did not differ from each other in any of the hypsodonty indexes. We conclude that the adaptation to different dietary types in most of the oral traits studied is subsumed by the effects of body mass and the sharing of common ancestors. We hypothesize that differences in the ability to exploit different food resources primarily result from differences in body mass between species, and also discuss why hypsodonty characterizes feeding styles.

  15. Relationships between oral morphology and feeding style in the Ungulata: a phylogenetically controlled evaluation.

    PubMed Central

    Pérez-Barbería, F. J.; Gordon, I. J.

    2001-01-01

    In ungulates it is argued that specialization in the consumption of a particular type of food (feeding style) is reflected in morphological adaptations of the organs involved in the selection, processing and digestion of food. We analysed the differences in size and morphology of some oral traits that have been functionally related to food-selection ability (muzzle width, incisor-arcade shape, incisor shape), prehension of food (incisor protrusion), food comminution (molar occlusal surface area, hypsodonty (high-crowned molars)) and intake rate (incisor breadth) between ungulate species with different feeding styles (browser, mixed feeder, grazer). Grazers were characterized by large-body-size species. After controlling only for body mass, we found that grazers had wider muzzles and incisors, more-protruding incisors and more-bulky and higher-crowned molars than did mixed feeders and browsers. When the analyses took into account both body mass and phylogeny, only body mass and two out of the three hypsodonty indexes used remained significantly different between feeding styles. Browsers were smaller, on average, than mixed feeders and grazers, whilst grazers and mixed feeders did not differ in size. Also, browsers had shorter and less-bulky molars than did mixed feeders and grazers; the latter two feeding styles did not differ from each other in any of the hypsodonty indexes. We conclude that the adaptation to different dietary types in most of the oral traits studied is subsumed by the effects of body mass and the sharing of common ancestors. We hypothesize that differences in the ability to exploit different food resources primarily result from differences in body mass between species, and also discuss why hypsodonty characterizes feeding styles. PMID:11375086

  16. Trophic niche of squids: Insights from isotopic data in marine systems worldwide

    NASA Astrophysics Data System (ADS)

    Navarro, Joan; Coll, Marta; Somes, Christoper J.; Olson, Robert J.

    2013-10-01

    Cephalopods are an important prey resource for fishes, seabirds, and marine mammals, and are also voracious predators on crustaceans, fishes, squid and zooplankton. Because of their high feeding rates and abundance, squids have the potential to exert control on the recruitment of commercially important fishes. In this review, we synthesize the available information for two intrinsic markers (δ15N and δ13C isotopic values) in squids for all oceans and several types of ecosystems to obtain a global view of the trophic niches of squids in marine ecosystems. In particular, we aimed to examine whether the trophic positions and trophic widths of squid species vary among oceans and ecosystem types. To correctly compare across systems, we adjusted squid δ15N values for the isotopic variability of phytoplankton at the base of the food web provided by an ocean circulation-biogeochemistry-isotope model. Studies that focused on the trophic ecology of squids using isotopic techniques were few, and most of the information on squids was from studies on their predators. Our results showed that squids occupy a large range of trophic positions and exploit a large range of trophic resources, reflecting the versatility of their feeding behavior and confirming conclusions from food-web models. Clear differences in both trophic position and trophic width were found among oceans and ecosystem types. The study also reinforces the importance of considering the natural variation in isotopic values when comparing the isotopic values of consumers inhabiting different ecosystems.

  17. Partitioning ecosystems for sustainability.

    PubMed

    Murray, Martyn G

    2016-03-01

    Decline in the abundance of renewable natural resources (RNRs) coupled with increasing demands of an expanding human population will greatly intensify competition for Earth's natural resources during this century, yet curiously, analytical approaches to the management of productive ecosystems (ecological theory of wildlife harvesting, tragedy of the commons, green economics, and bioeconomics) give only peripheral attention to the driving influence of competition on resource exploitation. Here, I apply resource competition theory (RCT) to the exploitation of RNRs and derive four general policies in support of their sustainable and equitable use: (1) regulate resource extraction technology to avoid damage to the resource base; (2) increase efficiency of resource use and reduce waste at every step in the resource supply chain and distribution network; (3) partition ecosystems with the harvesting niche as the basic organizing principle for sustainable management of natural resources by multiple users; and (4) increase negative feedback between consumer and resource to bring about long-term sustainable use. A simple policy framework demonstrates how RCT integrates with other elements of sustainability science to better manage productive ecosystems. Several problem areas of RNR management are discussed in the light of RCT, including tragedy of the commons, overharvesting, resource collapse, bycatch, single species quotas, and simplification of ecosystems.

  18. Evaluation of the Zooplankton Community of Livingston Reservoir, Texas, as Related to Paddlefish Food Resources

    DTIC Science & Technology

    1993-12-01

    EVALUATION OF THE ZOOPLANKTON COMMUNITY OF LIVINGSTON RESERVOIR. TEXAS, AS RELATED TO PADDLEFISH FOOD RESOURCES A Thesis by CASEY KENNETH MOORE...OF LIVINGSTON RESERVOIR, TEXAS. AS RELATED TO PADDLEFISH FOOD RESOURCES A Thesis by CASEY KENNETH MOORE Submitted to Texas A&M University in partial...Fisheries Sciences iii ABSTRACT Evaluation of the Zooplankton Community of Livingston Reservoir, Texas, as Related to Paddlefish Food Resources

  19. The determination of methane resources from liquidated coal mines

    NASA Astrophysics Data System (ADS)

    Trenczek, Stanisław

    2017-11-01

    The article refers to methane presented in hard coal seams, which may pose a serious risk to workers, as evidenced by examples of incidents, and may also be a high energy source. That second issue concerns the possibility of obtaining methane from liquidated coal mines. There is discussed the current methodology for determination of methane resources from hard coal deposits. Methods of assessing methane emissions from hard coal deposits are given, including the degree of rock mass fracture, which is affected and not affected by mining. Additional criteria for methane recovery from the methane deposit are discussed by one example (of many types) of methane power generation equipment in the context of the estimation of potential viable resources. Finally, the concept of “methane resource exploitation from coal mine” refers to the potential for exploitation of the resource and the acquisition of methane for business purposes.

  20. The impact of gold mining and agricultural concessions on the tree cover and local communities in northern Myanmar.

    PubMed

    Papworth, Sarah; Rao, Madhu; Oo, Myint Myint; Latt, Kyaw Thinn; Tizard, Robert; Pienkowski, Thomas; Carrasco, L Roman

    2017-04-24

    Myanmar offers unique opportunities for both biodiversity conservation and foreign direct investment due to projected economic growth linked to natural resource exploitation. Industrial-scale development introduces new land uses into the landscape, with unknown repercussions for local communities and biodiversity conservation. We use participatory mapping of 31 communities, focus groups in 28 communities, and analyses of forest cover change during 2000-2010 using MODIS vegetation continuous fields images, to understand the social and environmental impacts of gold mining and agricultural concessions in Myanmar's Hukaung Valley (~21,800 km 2 ). Local communities, particularly the poorest households, benefit from work and trade opportunities offered by gold mining and agricultural companies but continue to depend on forests for house construction materials, food, and income from the sale of forest resources. However, gold mining and agricultural concessions reduce tree cover, potentially reducing access to forest resources and further marginalizing these households. Our analyses do not provide evidence that long-term resident communities contributed to forest cover loss between 2000 and 2010. We argue that landscape management, which recognizes local community rights to customary community use areas, and appropriate zoning for commercial land uses and protected areas could contribute to both local livelihoods and protect biodiversity throughout Myanmar during economic growth.

  1. The impact of gold mining and agricultural concessions on the tree cover and local communities in northern Myanmar

    PubMed Central

    Papworth, Sarah; Rao, Madhu; Oo, Myint Myint; Latt, Kyaw Thinn; Tizard, Robert; Pienkowski, Thomas; Carrasco, L. Roman

    2017-01-01

    Myanmar offers unique opportunities for both biodiversity conservation and foreign direct investment due to projected economic growth linked to natural resource exploitation. Industrial-scale development introduces new land uses into the landscape, with unknown repercussions for local communities and biodiversity conservation. We use participatory mapping of 31 communities, focus groups in 28 communities, and analyses of forest cover change during 2000–2010 using MODIS vegetation continuous fields images, to understand the social and environmental impacts of gold mining and agricultural concessions in Myanmar’s Hukaung Valley (~21,800 km2). Local communities, particularly the poorest households, benefit from work and trade opportunities offered by gold mining and agricultural companies but continue to depend on forests for house construction materials, food, and income from the sale of forest resources. However, gold mining and agricultural concessions reduce tree cover, potentially reducing access to forest resources and further marginalizing these households. Our analyses do not provide evidence that long-term resident communities contributed to forest cover loss between 2000 and 2010. We argue that landscape management, which recognizes local community rights to customary community use areas, and appropriate zoning for commercial land uses and protected areas could contribute to both local livelihoods and protect biodiversity throughout Myanmar during economic growth. PMID:28436455

  2. Rural and indigenous women speak out on the impact of globalization.

    PubMed

    Kelkar, G

    1998-01-01

    This article describes approach papers, proposed strategies, and closing agreements among those attending the May 1998 Asian Pacific Forum on Women, Law, and Development (APWLD) among rural, indigenous women (IW). IW spoke of their experiences with globalization. The aim was to examine the effects of deregulation and privatization, liberalization, and global market and foreign monopoly capital on rural, IW in Asia. The expected outcome was an advocacy directive for APWLD in the forthcoming APEC and People's Summit in November 1998. Approach papers included F. N. Burnad's paper on the "Impact of Globalization on Rural Women" and V. Tauli-Corpuz's paper on "Globalization and its Impacts on Indigenous Women: The Philippine Experience." These papers emphasized the multiple roles of women, their increasing resourcefulness which leads to their enslavement, links between globalization and continuing colonization by transnationals and international institutions, access to ancestral resources, and promotion of export led production that threatens food security. Suggested strategies were to mobilize opposition to globalization and greater control over traditional resources and knowledge by IW. Several important questions were raised about nation states, dominant cultures, human rights violations, technology, and the close link between militarization and globalization. Participants agreed to mobilize for effectively resisting and eliminating unjust and unequal systems that exploit and oppress rural, poor, and indigenous people, especially women.

  3. Measures for increased nutrition and utilization of non-conventional food resources during disasters in Africa.

    PubMed

    Nur, I M

    1999-01-01

    The basic causes of the poor performance of the food and agricultural sector in the different parts of Africa are external, internal, and natural. The general recession in the Continent limits the capacity of the respective countries to import food to supplement inadequate domestic production and supplies. There are a number of nutritious food resources, both cultivated and gathered in the different ecological zones of Africa, whose production and consumption can be increased to ensure adequate food security and a nutritious diet, especially during disasters. These food resources could include: cereals, legumes, fruits, vegetables, fish, and insects. These food resources already are available over wide geographical areas in Africa and are utilized or utilized to a limited extent. Therefore, strategies to increase food supply, eradicate hunger and malnutrition, and keep people alive in times of disasters should have as a priority, the cultivation and consumption of non-conventional food resources in the respective communities and countries.

  4. Arctic Climate Change, Economy and Society (ACCESS): Integrated perspectives.

    PubMed

    Crépin, Anne-Sophie; Karcher, Michael; Gascard, Jean-Claude

    2017-12-01

    This introduction to the special issue presents an overview of the wide range of results produced during the European Union project Arctic Climate Change, Economy and Society (ACCESS). This project assessed the main impacts of climate change on Arctic Ocean's geophysical variables and how these impending changes could be expected to impact directly and indirectly on socio-economic activities like transportation, marine sea food production and resource exploitation. Related governance issues were examined. These results were used to develop several management tools that can live on beyond ACCESS. In this article, we synthesize most of the project results in the form of tentative responses to questions raised during the project. By doing so, we put the findings of the project in a broader perspective and introduce the contributions made in the different articles published in this special issue.

  5. Stable isotope analysis of larval mosquito diets in agricultural wetlands in the coastal plain of Georgia, U.S.A.

    PubMed

    Young, Gina Botello; Golladay, Stephen; Covich, Alan; Blackmore, Mark

    2014-12-01

    Previous studies have used C and N isotope ratios to investigate the use of different food resources such as plant and animal detritus by container-breeding mosquitoes. This study is the first to report on the potential food resources assimilated by larval mosquitoes in agricultural and reference wetlands. Larval mosquitoes (Diptera: Culcidae) were sampled, along with their potential food resources, from agricultural and reference wetland habitats throughout a seasonal hydroperiod. IsoSource mixing model results indicated that food resources had greater δ(15) N isotope values in agricultural wetlands compared with cypress-gum swamps. In February, Aedes vexans (Meigen) and Culex territans Walker larvae fed primarily on lower quality food resources (coarse particulate organic matter and sediment) based on C:N. In contrast, higher quality food resources (fine particulate organic matter) were utilized by Anopheles spp. throughout the study and by Psorophora columbiae (Dyer and Knab) in May. This research contributes to a more comprehensive understanding of the food resources available and assimilated by larval mosquitoes in agricultural wetlands. © 2014 The Society for Vector Ecology.

  6. Timing of cyber conflict.

    PubMed

    Axelrod, Robert; Iliev, Rumen

    2014-01-28

    Nations are accumulating cyber resources in the form of stockpiles of zero-day exploits as well as other novel methods of engaging in future cyber conflict against selected targets. This paper analyzes the optimal timing for the use of such cyber resources. A simple mathematical model is offered to clarify how the timing of such a choice can depend on the stakes involved in the present situation, as well as the characteristics of the resource for exploitation. The model deals with the question of when the resource should be used given that its use today may well prevent it from being available for use later. The analysis provides concepts, theory, applications, and distinctions to promote the understanding strategy aspects of cyber conflict. Case studies include the Stuxnet attack on Iran's nuclear program, the Iranian cyber attack on the energy firm Saudi Aramco, the persistent cyber espionage carried out by the Chinese military, and an analogous case of economic coercion by China in a dispute with Japan. The effects of the rapidly expanding market for zero-day exploits are also analyzed. The goal of the paper is to promote the understanding of this domain of cyber conflict to mitigate the harm it can do, and harness the capabilities it can provide.

  7. Review: Groundwater resources and related environmental issues in China

    NASA Astrophysics Data System (ADS)

    Hao, Aibing; Zhang, Yilong; Zhang, Eryong; Li, Zhenghong; Yu, Juan; Wang, Huang; Yang, Jianfeng; Wang, Yao

    2018-05-01

    As an important component of water resources, groundwater plays a crucial role in water utilization in China and an irreplaceable role in supporting economic and social development, especially in the northern arid and semi-arid plains and basin areas, which are densely populated and relatively short of surface-water resources. This paper comprehensively reviews and discusses the regional hydrogeological conditions, the temporal and spatial distribution of groundwater, the groundwater quality, and the actuality of groundwater exploitation and utilization in China. Meanwhile, aiming at the environmental problems induced by overexploitation to meet the sharply increasing water demand, this paper puts forward the major tasks for the next few years in terms of groundwater exploitation control, conservation and management.

  8. Research status of geothermal resources in China

    NASA Astrophysics Data System (ADS)

    Zhang, Lincheng; Li, Guang

    2017-08-01

    As the representative of the new green energy, geothermal resources are characterized by large reserve, wide distribution, cleanness and environmental protection, good stability, high utilization factor and other advantages. According to the characteristics of exploitation and utilization, they can be divided into high-temperature, medium-temperature and low-temperature geothermal resources. The abundant and widely distributed geothermal resources in China have a broad prospect for development. The medium and low temperature geothermal resources are broadly distributed in the continental crustal uplift and subsidence areas inside the plate, represented by the geothermal belt on the southeast coast, while the high temperature geothermal resources concentrate on Southern Tibet-Western Sichuan-Western Yunnan Geothermal Belt and Taiwan Geothermal Belt. Currently, the geothermal resources in China are mainly used for bathing, recuperation, heating and power generation. It is a country that directly makes maximum use of geothermal energy in the world. However, China’s geothermal power generation, including installed generating capacity and power generation capacity, are far behind those of Western European countries and the USA. Studies on exploitation and development of geothermal resources are still weak.

  9. Characterization of the seascape used by juvenile and wintering adult Southern Giant Petrels from Patagonia Argentina

    NASA Astrophysics Data System (ADS)

    Blanco, Gabriela S.; Pisoni, Juan P.; Quintana, Flavio

    2015-02-01

    The characterization of the seascape used by marine top predators provides a wide perspective of pelagic habitat use and it is necessary to understand the functioning of marine systems. The goal of this study was to characterize the oceanographic and biological features of marine areas used by adult and first year juvenile southern giant petrels (SGP, Macronectes giganteus) from northern Patagonian colonies (Isla Arce and Gran Robredo) during the austral fall and winter (2005, 2006, 2007, and 2008). The marine environment exploited by the SGP was characterized using sea surface temperature (SST), SST gradients, chlorophyll-a concentration, water depth, oceanographic regimes, and ocean surface winds. In addition, the biological seascape was defined by considering the distribution of squid during the months of study. Juveniles SGP exploited a wide range of environments focusing mainly on productive neritic waters using a variety of oceanographic regimes. Juveniles were exposed to eutrophic and enriched waters, probably because of the frequent presence of thermal fronts in their utilization areas. Adults' environments lacked of thermal fronts remaining the majority of their time within the oceanographic regime "Continental Shelf", in water depths of 100-200 m, exploiting mesotrophic and eutrophic environments, and remaining in areas of known food resources related to the presence of squid. For the most part, juveniles were exposed to westerly winds, which may have helped them in their initial flight to the shelf break, east of the colony. Wintering adults SGP also explored areas characterized by westerly winds but this did not play a primary role in the selection of their residence areas. Juveniles during their first year at sea have to search for food exploring a variety of unknown environments. During their search, they remained in productive environments associated to fronts and probably also associated to fisheries operating in their foraging areas. The understanding of pelagic birds' habitat selection and preferences through the year is crucial for the monitoring of anthropogenic impacts over these species. Further studies should focus on the prediction of variables that determine the distribution of these species though the year and during different life stages.

  10. Teotihuacan, tepeapulco, and obsidian exploitation.

    PubMed

    Charlton, T H

    1978-06-16

    Current cultural ecological models of the development of civilization in central Mexico emphasize the role of subsistence production techniques and organization. The recent use of established and productive archeological surface survey techniques along natural corridors of communication between favorable niches for cultural development within the Central Mexican symbiotic region resulted in the location of sites that indicate an early development of a decentralized resource exploitation, manufacturing, and exchange network. The association of the development of this system with Teotihuacán indicates the importance such nonsubsistence production and exchange had in the evolution of this first central Mexican civilization. The later expansion of Teotihuacán into more distant areas of Mesoamerica was based on this resource exploitation model. Later civilizations centered at Tula and Tenochtitlán also used such a model in their expansion.

  11. Marine Resources and Legal-Political Arrangements for Their Development; Volume 3, Panel Reports of the Commission on Marine Science, Engineering and Resources.

    ERIC Educational Resources Information Center

    Commission on Marine Science, Engineering and Resources, Washington, DC.

    The Marine Resources Panel addressed itself to three tasks: describing the current rate of exploration and exploitation of marine resources and the physical, economic, and legal conditions under which they are produced; identifying deterrents to development and efficient utilization of marine resources; and recommending programs that will remove…

  12. A Sushi Science Module in Food Production Systems and Aquatic Resource Education

    ERIC Educational Resources Information Center

    Livengood, Elisa J.; Chapman, Frank A.

    2009-01-01

    No other food industry depends so heavily on a wild caught resource than those associated with aquatic food products. Domestication of fish, shellfish, and other aquatic resources production has lagged behind other terrestrial livestock products; however, demand for these aquatic natural resources has continued to increase dramatically. Teaching…

  13. A systematic review of wild grass exploitation in relation to emerging cereal cultivation throughout the Epipalaeolithic and aceramic Neolithic of the Fertile Crescent.

    PubMed

    Weide, Alexander; Riehl, Simone; Zeidi, Mohsen; Conard, Nicholas J

    2018-01-01

    The present study investigates the occurrence of wild grasses at Epipalaeolithic and aceramic Neolithic sites in the Near East in order to assess their role in subsistence economies alongside the emergence of cereal cultivation. We use Chogha Golan in the foothills of the central Zagros Mountains (ca. 11.7-9.6 ka cal. BP) as a case study, where the archaeobotanical data suggest the frequent exploitation of a complex of wild grasses for almost 2,000 years. Domesticated emmer replaced these wild grasses as the major food resources towards the end of occupation at the site (ca. 9.8 ka cal. BP). We discuss possible implications of this development and conclude that the traditional concept of pre-domestication cultivation seems unsuited for explaining the patterns from Chogha Golan. These data are in good accordance with the overall picture in the Zagros Mountains, where wild grasses were routinely gathered throughout the early Holocene. In contrast, wild grasses were gradually replaced by wild cereals in the Levantine corridor since the end of the Pleistocene. However, several sites located in this region provide evidence for a continuous exploitation of wild grasses alongside emerging cereal cultivation and most of these taxa were part of the earliest segetal floras that evolved with the appearance of domestic cereals throughout the 11th millennium cal. BP. Some sites contemporary to the Pre-Pottery Neolithic B still provide evidence for the usage of wild grasses, which possibly reflects the utilization of edible arable weeds and continuous gathering of wild grasses by more mobile groups.

  14. Investigating tangible and mental resources as predictors of perceived household food insecurity during pregnancy among women in a South African birth cohort study.

    PubMed

    Pellowski, Jennifer A; Barnett, Whitney; Kuo, Caroline C; Koen, Nastassja; Zar, Heather J; Stein, Dan J

    2017-08-01

    Food insecurity during pregnancy is concerning given the increased nutritional needs of the mother for proper fetal development. However, research is lacking within the South African context to investigate the association of economic and psychosocial factors and food insecurity among pregnant women, using comprehensive, conceptually driven models. This study applies the Network-Individual-Resource (NIR) Model to investigate individual, intimate dyadic, and family level predictors of perceived household food insecurity for pregnant women. 826 pregnant women enrolled in the Drakenstein Child Health Study (DCHS), a birth cohort in two communities in a peri-urban area of South Africa. Hierarchical logistic regressions were used to investigate the impact of household/family, intimate dyads, and individual tangible and mental resources on perceived household food insecurity during the critical period of pregnancy. Perceived household food insecurity was assessed through an adapted version of the USDA Household Food Security Scale - Short Form. Among 826 pregnant women in South Africa, individual-level tangible resources (e.g. income, social assistance, HIV status) and mental resources (e. g. depression, childhood trauma) predicted perceived household food insecurity and these predictors differed by community. Intimate dyadic and family level resources did not predict household food insecurity. Our findings of the economic and psychosocial predictors of perceived household food insecurity among pregnant women in South Africa, mirror findings in general populations. This study provides support for the extension of the NIR model to perceived household food insecurity, particularly regarding individual-level mental and tangible resources, as well as the impact of community-level factors. Future research should investigate the extent to which resource sharing occurs within networks. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Local descriptive body weight and dietary norms, food availability, and 10-year change in glycosylated haemoglobin in an Australian population-based biomedical cohort.

    PubMed

    Carroll, Suzanne J; Paquet, Catherine; Howard, Natasha J; Coffee, Neil T; Adams, Robert J; Taylor, Anne W; Niyonsenga, Theo; Daniel, Mark

    2017-02-02

    Individual-level health outcomes are shaped by environmental risk conditions. Norms figure prominently in socio-behavioural theories yet spatial variations in health-related norms have rarely been investigated as environmental risk conditions. This study assessed: 1) the contributions of local descriptive norms for overweight/obesity and dietary behaviour to 10-year change in glycosylated haemoglobin (HbA 1c ), accounting for food resource availability; and 2) whether associations between local descriptive norms and HbA 1c were moderated by food resource availability. HbA 1c , representing cardiometabolic risk, was measured three times over 10 years for a population-based biomedical cohort of adults in Adelaide, South Australia. Residential environmental exposures were defined using 1600 m participant-centred road-network buffers. Local descriptive norms for overweight/obesity and insufficient fruit intake (proportion of residents with BMI ≥ 25 kg/m 2 [n = 1890] or fruit intake of <2 serves/day [n = 1945], respectively) were aggregated from responses to a separate geocoded population survey. Fast-food and healthful food resource availability (counts) were extracted from a retail database. Separate sets of multilevel models included different predictors, one local descriptive norm and either fast-food or healthful food resource availability, with area-level education and individual-level covariates (age, sex, employment status, education, marital status, and smoking status). Interactions between local descriptive norms and food resource availability were tested. HbA 1c concentration rose over time. Local descriptive norms for overweight/obesity and insufficient fruit intake predicted greater rates of increase in HbA 1c . Neither fast-food nor healthful food resource availability were associated with change in HbA 1c . Greater healthful food resource availability reduced the rate of increase in HbA 1c concentration attributed to the overweight/obesity norm. Local descriptive health-related norms, not food resource availability, predicted 10-year change in HbA 1c . Null findings for food resource availability may reflect a sufficiency or minimum threshold level of resources such that availability poses no barrier to obtaining healthful or unhealthful foods for this region. However, the influence of local descriptive norms varied according to food resource availability in effects on HbA 1c . Local descriptive health-related norms have received little attention thus far but are important influences on individual cardiometabolic risk. Further research is needed to explore how local descriptive norms contribute to chronic disease risk and outcomes.

  16. Intellectual Property Rights in the Australian University Context: An Overview.

    ERIC Educational Resources Information Center

    Ricketson, Sam

    1993-01-01

    The existing legal position of Australian universities with respect to ownership and exploitation of intellectual property by faculty, students, and outside consultants is described. Issues requiring attention are noted, including resources for exploitation, sharing of proceeds, and copyright considerations; and some possible solutions are…

  17. Lactic Acid Bacteria Exopolysaccharides in Foods and Beverages: Isolation, Properties, Characterization, and Health Benefits.

    PubMed

    Lynch, Kieran M; Zannini, Emanuele; Coffey, Aidan; Arendt, Elke K

    2018-03-25

    Exopolysaccharides produced by lactic acid bacteria are a diverse group of polysaccharides produced by many species. They vary widely in their molecular, compositional, and structural characteristics, including mechanisms of synthesis. The physiochemical properties of these polymers mean that they can be exploited for the sensorial and textural enhancement of a variety of food and beverage products. Traditionally, lactic acid bacteria exopolysaccharides have an important role in fermented dairy products and more recently are being applied for the improvement of bakery products. The health benefits that are continually being associated with these polysaccharides enable the development of dual function, added-value, and clean-label products. To fully exploit and understand the functionality of these exopolysaccharides, their isolation, purification, and thorough characterization are of great importance. This review considers each of the above factors and presents the current knowledge on the importance of lactic acid bacteria exopolysaccharides in the food and beverage industry.

  18. Filamentous fungi for production of food additives and processing aids.

    PubMed

    Archer, David B; Connerton, Ian F; MacKenzie, Donald A

    2008-01-01

    Filamentous fungi are metabolically versatile organisms with a very wide distribution in nature. They exist in association with other species, e.g. as lichens or mycorrhiza, as pathogens of animals and plants or as free-living species. Many are regarded as nature's primary degraders because they secrete a wide variety of hydrolytic enzymes that degrade waste organic materials. Many species produce secondary metabolites such as polyketides or peptides and an increasing range of fungal species is exploited commercially as sources of enzymes and metabolites for food or pharmaceutical applications. The recent availability of fungal genome sequences has provided a major opportunity to explore and further exploit fungi as sources of enzymes and metabolites. In this review chapter we focus on the use of fungi in the production of food additives but take a largely pre-genomic, albeit a mainly molecular, view of the topic.

  19. Exploiting multicore compute resources in the CMS experiment

    NASA Astrophysics Data System (ADS)

    Ramírez, J. E.; Pérez-Calero Yzquierdo, A.; Hernández, J. M.; CMS Collaboration

    2016-10-01

    CMS has developed a strategy to efficiently exploit the multicore architecture of the compute resources accessible to the experiment. A coherent use of the multiple cores available in a compute node yields substantial gains in terms of resource utilization. The implemented approach makes use of the multithreading support of the event processing framework and the multicore scheduling capabilities of the resource provisioning system. Multicore slots are acquired and provisioned by means of multicore pilot agents which internally schedule and execute single and multicore payloads. Multicore scheduling and multithreaded processing are currently used in production for online event selection and prompt data reconstruction. More workflows are being adapted to run in multicore mode. This paper presents a review of the experience gained in the deployment and operation of the multicore scheduling and processing system, the current status and future plans.

  20. Energy for lunar resource exploitation

    NASA Astrophysics Data System (ADS)

    Glaser, Peter E.

    1992-02-01

    Humanity stands at the threshold of exploiting the known lunar resources that have opened up with the access to space. America's role in the future exploitation of space, and specifically of lunar resources, may well determine the level of achievement in technology development and global economic competition. Space activities during the coming decades will significantly influence the events on Earth. The 'shifting of history's tectonic plates' is a process that will be hastened by the increasingly insistent demands for higher living standards of the exponentially growing global population. Key to the achievement of a peaceful world in the 21st century, will be the development of a mix of energy resources at a societally acceptable and affordable cost within a realistic planning horizon. This must be the theme for the globally applicable energy sources that are compatible with the Earth's ecology. It is in this context that lunar resources development should be a primary goal for science missions to the Moon, and for establishing an expanding human presence. The economic viability and commercial business potential of mining, extracting, manufacturing, and transporting lunar resource based materials to Earth, Earth orbits, and to undertake macroengineering projects on the Moon remains to be demonstrated. These extensive activities will be supportive of the realization of the potential of space energy sources for use on Earth. These may include generating electricity for use on Earth based on beaming power from Earth orbits and from the Moon to the Earth, and for the production of helium 3 as a fuel for advanced fusion reactors.

  1. Energy for lunar resource exploitation

    NASA Technical Reports Server (NTRS)

    Glaser, Peter E.

    1992-01-01

    Humanity stands at the threshold of exploiting the known lunar resources that have opened up with the access to space. America's role in the future exploitation of space, and specifically of lunar resources, may well determine the level of achievement in technology development and global economic competition. Space activities during the coming decades will significantly influence the events on Earth. The 'shifting of history's tectonic plates' is a process that will be hastened by the increasingly insistent demands for higher living standards of the exponentially growing global population. Key to the achievement of a peaceful world in the 21st century, will be the development of a mix of energy resources at a societally acceptable and affordable cost within a realistic planning horizon. This must be the theme for the globally applicable energy sources that are compatible with the Earth's ecology. It is in this context that lunar resources development should be a primary goal for science missions to the Moon, and for establishing an expanding human presence. The economic viability and commercial business potential of mining, extracting, manufacturing, and transporting lunar resource based materials to Earth, Earth orbits, and to undertake macroengineering projects on the Moon remains to be demonstrated. These extensive activities will be supportive of the realization of the potential of space energy sources for use on Earth. These may include generating electricity for use on Earth based on beaming power from Earth orbits and from the Moon to the Earth, and for the production of helium 3 as a fuel for advanced fusion reactors.

  2. Maternal resources and household food security: evidence from Nicaragua.

    PubMed

    Schmeer, Kammi K; Piperata, Barbara A; Herrera Rodríguez, Andrés; Salazar Torres, Virgilio Mariano; Centeno Cárdenas, Francisco José

    2015-11-01

    Women (especially mothers) are theorized as critical to reducing household food insecurity through their work and caregiver roles. The present study tests these assumptions, assessing how maternal economic and social resources are associated with food insecurity in households with young children. Data from a population-based sample of households was collected in León, Nicaragua (n 443). Data include a newly validated measure of household food insecurity (ELCSA), maternal resource measures, and household economic status and demographics. Regression analysis tests the statistical associations (P<0·05) of maternal resources with household, adult-specific and child-specific food insecurity. Municipality of León, Nicaragua. Households with children aged 3-11 years in rural and urban León. Only 25% of households with young children were food secure, with 50% mildly food insecure and 25% moderately/severely food insecure. When mothers contributed substantially to household income, the odds of moderate/severe household food insecurity were 34% lower than when their spouse/partner was the main provider. The odds of food insecurity were 60% lower when mothers managed household money, 48% lower when mothers had a secondary (v. primary) education, 65% higher among single mothers and 16% lower with each indicator of social support. Results were similar for adult- and child-specific food insecurity. This research provides new evidence that maternal economic and social resources are important for reducing household food insecurity and adult- and child-specific food insecurity. Women's social status, social support and access to economic resources need to be enhanced as a part of policies aimed to reduce food insecurity in high-poverty settings.

  3. Making Meaning and Using Natural Resources: Education and Sustainability

    ERIC Educational Resources Information Center

    Stables, Andrew

    2010-01-01

    A natural resource is not given, but depends on human knowledge for its exploitation. Thus a "unit of resource" is, to a significant degree, a "unit of meaning", and education is potentially important not only for the use of resources but also for their creation. The paper draws on poststructuralism to confirm the intuition that it would be…

  4. A framework for unravelling the complexities of unsustainable water resource use

    NASA Astrophysics Data System (ADS)

    Dermody, Brian; Bierkens, Marc; Wassen, Martin; Dekker, Stefan

    2016-04-01

    The majority of unsustainable water resource use is associated with food production, with the agricultural sector accounting for up to 70% of total freshwater use by humans. Water resource use in food production emerges as a result of dynamic interactions between humans and their environment in importing and exporting regions as well as the physical and socioeconomic trade infrastructure linking the two. Thus in order to understand unsustainable water resource use, it is essential to understand the complex socioecological food production and trade system. We present a modelling framework of the food production and trade system that facilitates an understanding of complex socioenvironmental processes that lead to unsustainable water resource use. Our framework is based on a coupling of the global hydrological model PC Raster Global Water Balance (PCR-GLOBWB) with a multi-agent socioeconomic food production and trade network. In our framework, agents perceive environmental conditions. They make food supply decisions based upon those perceptions and the heterogeneous socioeconomic conditions in which they exist. Agent decisions modify land and water resources. Those environmental changes feedback to influence decision making further. The framework presented has the potential to go beyond a diagnosis of the causes of unsustainable water resource and provide pathways towards a sustainable food system in terms of water resources.

  5. Indigenous food ingredients for complementary food formulations to combat infant malnutrition in Benin: a review.

    PubMed

    Chadare, Flora J; Madode, Yann E; Fanou-Fogny, Nadia; Kindossi, Janvier M; Ayosso, Juvencio Og; Honfo, S Hermann; Kayodé, Ap Polycarpe; Linnemann, Anita R; Hounhouigan, D Joseph

    2018-01-01

    This paper reviews indigenous Beninese food resources as potential ingredients for complementary infant foods with the aim to develop affordable formulations for low-income households in each agro-ecological zone of the country. Potential ingredients were selected on their documented nutritional value. The selected foods encompass 347 food resources, namely 297 plant products from home gardens or collected from natural vegetation and 50 animals, either domesticated or from the wild. The compiled data reveal that the distribution of the available food resources was unbalanced between agro-ecological zones. Only a few animal ingredients are obtainable in northern Benin. Most resources are seasonal, but their availability may be extended. A high variation was observed in energy and nutrient contents. Antinutritional factors were identified in some resources, but processing techniques were reported to reduce their presence in meals. In general, ingredients from local tree foods (Adansonia digitata, Parkia biglobosa) were adequate as sources of nutrients for complementary infant foods. Based on this review, local foods for the development of complementary food formulas for Beninese infants and children may be selected for each agro-ecological zone. The approach used is exemplary for other sub-Saharan African countries in need of complementary infant foods. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  6. Niche shifts and energetic condition of songbirds in response to phenology of food-resource availability in a high-elevation sagebrush ecosystem

    USGS Publications Warehouse

    Cutting, Kyle A.; Anderson, Michelle L.; Beever, Erik; Schroff, Sean; Korb, Nathan; Klaphake, Eric; McWilliams, Scott R.

    2016-01-01

    Seasonal fluctuations in food availability can affect diets of consumers, which in turn may influence the physiological state of individuals and shape intra- and inter-specific patterns of resource use. High-elevation ecosystems often exhibit a pronounced seasonal “pulse” in productivity, although few studies document how resource use and energetic condition by avian consumers change in relation to food-resource availability in these ecosystems. We tested the hypothesis that seasonal increases (pulses) in food resources in high-elevation sagebrush ecosystems result in 2 changes after the pulse, relative to the before-pulse period: (1) reduced diet breadth of, and overlap between, 2 sympatric sparrow species; and (2) enhanced energetic condition in both species. We tracked breeding-season diets using stable isotopes and energetic condition using plasma metabolites of Brewer's Sparrows (Spizella breweri), Vesper Sparrows (Pooecetes gramineus), and their food resources during 2011, and of only Brewer's Sparrows and their food resources during 2013. We quantify diet breadth and overlap between both species, along with coincident physiological consequences of temporal changes in resource use. After invertebrate biomass increased following periods of rainfall in 2011, dietary breadth decreased by 35% in Brewer's Sparrows and by 48% in Vesper Sparrows, while dietary overlap decreased by 88%. Energetic condition of both species increased when dietary overlap was lower and diet breadth decreased, after the rapid rise of food-resource availability. However, energetic condition of Brewer's Sparrows remained constant in 2013, a year with low precipitation and lack of a strong pulse in food resources, even though the species' dietary breadth again decreased that year. Our results indicate that diet breadth and overlap in these sparrow species inhabiting sagebrush ecosystems generally varied as predicted in relation to intra- and interannual changes in food resources, and this difference in diet was associated with improved energetic condition of sparrows at least in one year.

  7. Seaweeds: an opportunity for wealth and sustainable livelihood for coastal communities.

    PubMed

    Rebours, Céline; Marinho-Soriano, Eliane; Zertuche-González, José A; Hayashi, Leila; Vásquez, Julio A; Kradolfer, Paul; Soriano, Gonzalo; Ugarte, Raul; Abreu, Maria Helena; Bay-Larsen, Ingrid; Hovelsrud, Grete; Rødven, Rolf; Robledo, Daniel

    2014-01-01

    The European, Canadian, and Latin American seaweed industries rely on the sustainable harvesting of natural resources. As several countries wish to increase their activity, the harvest should be managed according to integrated and participatory governance regimes to ensure production within a long-term perspective. Development of regulations and directives enabling the sustainable exploitation of natural resources must therefore be brought to the national and international political agenda in order to ensure environmental, social, and economic values in the coastal areas around the world. In Europe, Portugal requires an appraisal of seaweed management plans while Norway and Canada have developed and implemented coastal management plans including well-established and sustainable exploitation of their natural seaweed resources. Whereas, in Latin America, different scenarios of seaweed exploitation can be observed; each country is however in need of long-term and ecosystem-based management plans to ensure that exploitation is sustainable. These plans are required particularly in Peru and Brazil, while Chile has succeeded in establishing a sustainable seaweed-harvesting plan for most of the economically important seaweeds. Furthermore, in both Europe and Latin America, seaweed aquaculture is at its infancy and development will have to overcome numerous challenges at different levels (i.e., technology, biology, policy). Thus, there is a need for regulations and establishment of "best practices" for seaweed harvesting, management, and cultivation. Trained human resources will also be required to provide information and education to the communities involved, to enable seaweed utilization to become a profitable business and provide better income opportunities to coastal communities.

  8. Perceived barriers in accessing food among recent Latin American immigrants in Toronto

    PubMed Central

    2013-01-01

    Objective In Canada, recent immigrant households experience more food insecurity than the general population, but limited information is available about the personal, cultural, and social factors that contribute to this vulnerability. This study focused on recent Latin American (LA) immigrants to explore their perceived barriers in acquiring safe, nutritious, and culturally-appropriate food. Design A cross-sectional mixed-method design was applied to collect information from a convenience sample of 70 adult Spanish/Portuguese speakers who had arrived in Toronto within the last five years. Face-to-face interviews were conducted with primary household caregivers to obtain responses about barriers to acquiring food for their households; data were analyzed using a thematic analysis technique. Results Four main categories of barriers were identified: limited financial resources; language difficulty; cultural food preferences; and poor knowledge of available community-based food resources and services. Inadequate income was the main impediment in accessing adequate food, and was related to affordability of food items, accessibility of food outlets and transportation cost, and limited time for grocery shopping due to work conditions. Language barriers affected participants’ ability to obtain well-paid employment and their awareness about and access to available community-based food resources. Cultural barriers were related to food preferences and limited access to culturally-appropriate foods and resources. Conclusion The main barrier to food security among our sample of LA newcomers to Toronto is limited financial resources, highlighting the need for policies and strategies that could improve their financial power to purchase sufficient, nutritious, and culturally-acceptable food. Linguistic barriers and limited information among newcomers suggest the need to provide linguistically- and culturally-appropriate information related to community-based food programs and resources, as well as accessible subsidized English language programs, in the community and at workplaces. Participatory community-based food programs can augment, in a socially acceptable manner, food resources and reduce the social stigma attached to food charity. Finally, it is crucial to monitor and evaluate existing social and community-based services for their accessibility, cultural appropriateness and diversity, and effectiveness. PMID:23286318

  9. Direct evidence of milk consumption from ancient human dental calculus.

    PubMed

    Warinner, C; Hendy, J; Speller, C; Cappellini, E; Fischer, R; Trachsel, C; Arneborg, J; Lynnerup, N; Craig, O E; Swallow, D M; Fotakis, A; Christensen, R J; Olsen, J V; Liebert, A; Montalva, N; Fiddyment, S; Charlton, S; Mackie, M; Canci, A; Bouwman, A; Rühli, F; Gilbert, M T P; Collins, M J

    2014-11-27

    Milk is a major food of global economic importance, and its consumption is regarded as a classic example of gene-culture evolution. Humans have exploited animal milk as a food resource for at least 8500 years, but the origins, spread, and scale of dairying remain poorly understood. Indirect lines of evidence, such as lipid isotopic ratios of pottery residues, faunal mortality profiles, and lactase persistence allele frequencies, provide a partial picture of this process; however, in order to understand how, where, and when humans consumed milk products, it is necessary to link evidence of consumption directly to individuals and their dairy livestock. Here we report the first direct evidence of milk consumption, the whey protein β-lactoglobulin (BLG), preserved in human dental calculus from the Bronze Age (ca. 3000 BCE) to the present day. Using protein tandem mass spectrometry, we demonstrate that BLG is a species-specific biomarker of dairy consumption, and we identify individuals consuming cattle, sheep, and goat milk products in the archaeological record. We then apply this method to human dental calculus from Greenland's medieval Norse colonies, and report a decline of this biomarker leading up to the abandonment of the Norse Greenland colonies in the 15(th) century CE.

  10. Hitchhiker's guide to multi-dimensional plant pathology.

    PubMed

    Saunders, Diane G O

    2015-02-01

    Filamentous pathogens pose a substantial threat to global food security. One central question in plant pathology is how pathogens cause infection and manage to evade or suppress plant immunity to promote disease. With many technological advances over the past decade, including DNA sequencing technology, an array of new tools has become embedded within the toolbox of next-generation plant pathologists. By employing a multidisciplinary approach plant pathologists can fully leverage these technical advances to answer key questions in plant pathology, aimed at achieving global food security. This review discusses the impact of: cell biology and genetics on progressing our understanding of infection structure formation on the leaf surface; biochemical and molecular analysis to study how pathogens subdue plant immunity and manipulate plant processes through effectors; genomics and DNA sequencing technologies on all areas of plant pathology; and new forms of collaboration on accelerating exploitation of big data. As we embark on the next phase in plant pathology, the integration of systems biology promises to provide a holistic perspective of plant–pathogen interactions from big data and only once we fully appreciate these complexities can we design truly sustainable solutions to preserve our resources.

  11. Direct evidence of milk consumption from ancient human dental calculus

    PubMed Central

    Warinner, C.; Hendy, J.; Speller, C.; Cappellini, E.; Fischer, R.; Trachsel, C.; Arneborg, J.; Lynnerup, N.; Craig, O. E.; Swallow, D. M.; Fotakis, A.; Christensen, R. J.; Olsen, J. V.; Liebert, A.; Montalva, N.; Fiddyment, S.; Charlton, S.; Mackie, M.; Canci, A.; Bouwman, A.; Rühli, F.; Gilbert, M. T. P.; Collins, M. J.

    2014-01-01

    Milk is a major food of global economic importance, and its consumption is regarded as a classic example of gene-culture evolution. Humans have exploited animal milk as a food resource for at least 8500 years, but the origins, spread, and scale of dairying remain poorly understood. Indirect lines of evidence, such as lipid isotopic ratios of pottery residues, faunal mortality profiles, and lactase persistence allele frequencies, provide a partial picture of this process; however, in order to understand how, where, and when humans consumed milk products, it is necessary to link evidence of consumption directly to individuals and their dairy livestock. Here we report the first direct evidence of milk consumption, the whey protein β-lactoglobulin (BLG), preserved in human dental calculus from the Bronze Age (ca. 3000 BCE) to the present day. Using protein tandem mass spectrometry, we demonstrate that BLG is a species-specific biomarker of dairy consumption, and we identify individuals consuming cattle, sheep, and goat milk products in the archaeological record. We then apply this method to human dental calculus from Greenland's medieval Norse colonies, and report a decline of this biomarker leading up to the abandonment of the Norse Greenland colonies in the 15th century CE. PMID:25429530

  12. Exploiting short-term memory in soft body dynamics as a computational resource.

    PubMed

    Nakajima, K; Li, T; Hauser, H; Pfeifer, R

    2014-11-06

    Soft materials are not only highly deformable, but they also possess rich and diverse body dynamics. Soft body dynamics exhibit a variety of properties, including nonlinearity, elasticity and potentially infinitely many degrees of freedom. Here, we demonstrate that such soft body dynamics can be employed to conduct certain types of computation. Using body dynamics generated from a soft silicone arm, we show that they can be exploited to emulate functions that require memory and to embed robust closed-loop control into the arm. Our results suggest that soft body dynamics have a short-term memory and can serve as a computational resource. This finding paves the way towards exploiting passive body dynamics for control of a large class of underactuated systems. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  13. 7 CFR 210.14 - Resource management.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 4 2011-01-01 2011-01-01 false Resource management. 210.14 Section 210.14 Agriculture... Participation § 210.14 Resource management. (a) Nonprofit school food service. School food authorities shall.... Expenditures of nonprofit school food service revenues shall be in accordance with the financial management...

  14. 7 CFR 210.14 - Resource management.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 4 2014-01-01 2014-01-01 false Resource management. 210.14 Section 210.14 Agriculture... Participation § 210.14 Resource management. (a) Nonprofit school food service. School food authorities shall.... Expenditures of nonprofit school food service revenues shall be in accordance with the financial management...

  15. 7 CFR 210.14 - Resource management.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 4 2010-01-01 2010-01-01 false Resource management. 210.14 Section 210.14 Agriculture... Participation § 210.14 Resource management. (a) Nonprofit school food service. School food authorities shall.... Expenditures of nonprofit school food service revenues shall be in accordance with the financial management...

  16. Patterns of resource partitioning by nesting herons and ibis: how are odonata exploited?

    PubMed

    Samraoui, Farrah; Nedjah, Riad; Boucheker, Abdennour; Alfarhan, Ahmed H; Samraoui, Boudjéma

    2012-04-01

    Herons and ibis are colonially nesting waders which, owing to their number, mobility and trophic role as top predators, play a key role in aquatic ecosystems. They are also good biological models to investigate interspecific competition between sympatric species and predation; two processes which structure ecological communities. Odonata are also numerous, diverse, mobile and can play an important role in aquatic ecosystems by serving as prey for herons and ibis. A relationship between prey size and bird predator has been observed in Numidia wetlands (NE Algeria) after analyzing food boluses regurgitated by six species of birds (Purple Heron, Black-crowned Night Heron, Glossy Ibis, Little Egret, Squacco Heron and Cattle Egret) during the breeding period, which also shows a temporal gradient for the six species. Both the Levins index and preliminary multivariate analysis of the Odonata as prey fed to nestling herons and ibis, indicated a high degree of resource overlap. However, a distinction of prey based on taxonomy (suborder and family) and developmental stage (larvae or adults) reveals a clear size dichotomy with large-sized predators (Purple Heron, Black-crowned Night Heron and Glossy Ibis) preying on large preys like Aeshnids and Libellulids and small-sized predators feeding mainly on small prey like Zygoptera. Overall, the resource utilization suggests a pattern of resource segregation by coexisting nesting herons and ibis based on the timing of reproduction, prey types, prey size and foraging microhabitats. Copyright © 2012 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  17. Evolution of sociality by natural selection on variances in reproductive fitness: evidence from a social bee.

    PubMed

    Stevens, Mark I; Hogendoorn, Katja; Schwarz, Michael P

    2007-08-29

    The Central Limit Theorem (CLT) is a statistical principle that states that as the number of repeated samples from any population increase, the variance among sample means will decrease and means will become more normally distributed. It has been conjectured that the CLT has the potential to provide benefits for group living in some animals via greater predictability in food acquisition, if the number of foraging bouts increases with group size. The potential existence of benefits for group living derived from a purely statistical principle is highly intriguing and it has implications for the origins of sociality. Here we show that in a social allodapine bee the relationship between cumulative food acquisition (measured as total brood weight) and colony size accords with the CLT. We show that deviations from expected food income decrease with group size, and that brood weights become more normally distributed both over time and with increasing colony size, as predicted by the CLT. Larger colonies are better able to match egg production to expected food intake, and better able to avoid costs associated with producing more brood than can be reared while reducing the risk of under-exploiting the food resources that may be available. These benefits to group living derive from a purely statistical principle, rather than from ecological, ergonomic or genetic factors, and could apply to a wide variety of species. This in turn suggests that the CLT may provide benefits at the early evolutionary stages of sociality and that evolution of group size could result from selection on variances in reproductive fitness. In addition, they may help explain why sociality has evolved in some groups and not others.

  18. Timing of cyber conflict

    PubMed Central

    Axelrod, Robert; Iliev, Rumen

    2014-01-01

    Nations are accumulating cyber resources in the form of stockpiles of zero-day exploits as well as other novel methods of engaging in future cyber conflict against selected targets. This paper analyzes the optimal timing for the use of such cyber resources. A simple mathematical model is offered to clarify how the timing of such a choice can depend on the stakes involved in the present situation, as well as the characteristics of the resource for exploitation. The model deals with the question of when the resource should be used given that its use today may well prevent it from being available for use later. The analysis provides concepts, theory, applications, and distinctions to promote the understanding strategy aspects of cyber conflict. Case studies include the Stuxnet attack on Iran’s nuclear program, the Iranian cyber attack on the energy firm Saudi Aramco, the persistent cyber espionage carried out by the Chinese military, and an analogous case of economic coercion by China in a dispute with Japan. The effects of the rapidly expanding market for zero-day exploits are also analyzed. The goal of the paper is to promote the understanding of this domain of cyber conflict to mitigate the harm it can do, and harness the capabilities it can provide. PMID:24474752

  19. East African wetland-catchment data base for sustainable wetland management

    NASA Astrophysics Data System (ADS)

    Leemhuis, Constanze; Amler, Esther; Diekkrüger, Bernd; Gabiri, Geofrey; Näschen, Kristian

    2016-10-01

    Wetlands cover an area of approx. 18 Mio ha in the East African countries of Kenya, Rwanda, Uganda and Tanzania, with still a relative small share being used for food production. Current upland agricultural use intensification in these countries due to demographic growth, climate change and globalization effects are leading to an over-exploitation of the resource base, followed by an intensification of agricultural wetland use. We aim on translating, transferring and upscaling knowledge on experimental test-site wetland properties, small-scale hydrological processes, and water related ecosystem services under different types of management from local to national scale. This information gained at the experimental wetland/catchment scale will be embedded as reference data within an East African wetland-catchment data base including catchment physical properties and a regional wetland inventory serving as a base for policy advice and the development of sustainable wetland management strategies.

  20. Evolution of mammalian migrations for refuge, breeding, and food.

    PubMed

    Gnanadesikan, Gitanjali E; Pearse, William D; Shaw, Allison K

    2017-08-01

    Many organisms migrate between distinct habitats, exploiting variable resources while profoundly affecting ecosystem services, disease spread, and human welfare. However, the very characteristics that make migration captivating and significant also make it difficult to study, and we lack a comprehensive understanding of which species migrate and why. Here we show that, among mammals, migration is concentrated within Cetacea and Artiodactyla but also diffusely spread throughout the class (found in 12 of 27 orders). We synthesize the many ecological drivers of round-trip migration into three types of movement-between breeding and foraging sites, between breeding and refuge sites, and continuous tracking of forage/prey-each associated with different traits (body mass, diet, locomotion, and conservation status). Our results provide only partial support for the hypothesis that migration occurs without phylogenetic constraint. Furthermore, our findings suggest that categorizing migration into these three types may aid predictions of migrants' responses to environmental changes.

  1. Leadership Learning Opportunities in Agriculture, Food, and Natural Resources Education: The Role of The Teacher

    ERIC Educational Resources Information Center

    McKim, Aaron J.; Pauley, C. M.; Velez, Jonathan J.; Sorensen, Tyson J.

    2017-01-01

    Learning environments combining agriculture, food, natural resources, and leadership knowledge and skills are increasingly essential in preparing students for future success. School-based agricultural education offers a premier context in which to teach leadership within agriculture, food, and natural resources curriculum. However, providing…

  2. The Energetic Value of Land-Based Foods in Western Hudson Bay and Their Potential to Alleviate Energy Deficits of Starving Adult Male Polar Bears

    PubMed Central

    Gormezano, Linda J.; Rockwell, Robert F.

    2015-01-01

    Climate change is predicted to expand the ice-free season in western Hudson Bay and when it grows to 180 days, 28–48% of adult male polar bears are projected to starve unless nutritional deficits can be offset by foods consumed on land. We updated a dynamic energy budget model developed by Molnar et al. to allow influx of additional energy from novel terrestrial foods (lesser snow geese, eggs, caribou) that polar bears currently consume as part of a mixed diet while on land. We calculated the units of each prey, alone and in combination, needed to alleviate these lethal energy deficits under conditions of resting or limited movement (2 km d-1) prior to starvation. We further considered the total energy available from each sex and age class of each animal prey over the period they would overlap land-bound polar bears and calculated the maximum number of starving adult males that could be sustained on each food during the ice-free season. Our results suggest that the net energy from land-based food, after subtracting costs of limited movement to obtain it, could eliminate all projected nutritional deficits of starving adult male polar bears and likely other demographic groups as well. The hunting tactics employed, success rates as well as behavior and abundance of each prey will determine the realized energetic values for individual polar bears. Although climate change may cause a phenological mismatch between polar bears and their historical ice-based prey, it may simultaneously yield a new match with certain land-based foods. If polar bears can transition their foraging behavior to effectively exploit these resources, predictions for starvation-related mortality may be overestimated for western Hudson Bay. We also discuss potential complications with stable-carbon isotope studies to evaluate utilization of land-based foods by polar bears including metabolic effects of capture-related stress and consuming a mixed diet. PMID:26061693

  3. The Energetic Value of Land-Based Foods in Western Hudson Bay and Their Potential to Alleviate Energy Deficits of Starving Adult Male Polar Bears.

    PubMed

    Gormezano, Linda J; Rockwell, Robert F

    2015-01-01

    Climate change is predicted to expand the ice-free season in western Hudson Bay and when it grows to 180 days, 28-48% of adult male polar bears are projected to starve unless nutritional deficits can be offset by foods consumed on land. We updated a dynamic energy budget model developed by Molnar et al. to allow influx of additional energy from novel terrestrial foods (lesser snow geese, eggs, caribou) that polar bears currently consume as part of a mixed diet while on land. We calculated the units of each prey, alone and in combination, needed to alleviate these lethal energy deficits under conditions of resting or limited movement (2 km d-1) prior to starvation. We further considered the total energy available from each sex and age class of each animal prey over the period they would overlap land-bound polar bears and calculated the maximum number of starving adult males that could be sustained on each food during the ice-free season. Our results suggest that the net energy from land-based food, after subtracting costs of limited movement to obtain it, could eliminate all projected nutritional deficits of starving adult male polar bears and likely other demographic groups as well. The hunting tactics employed, success rates as well as behavior and abundance of each prey will determine the realized energetic values for individual polar bears. Although climate change may cause a phenological mismatch between polar bears and their historical ice-based prey, it may simultaneously yield a new match with certain land-based foods. If polar bears can transition their foraging behavior to effectively exploit these resources, predictions for starvation-related mortality may be overestimated for western Hudson Bay. We also discuss potential complications with stable-carbon isotope studies to evaluate utilization of land-based foods by polar bears including metabolic effects of capture-related stress and consuming a mixed diet.

  4. Effects of anthropogenic groundwater exploitation on land surface processes: A case study of the Haihe River Basin, northern China

    NASA Astrophysics Data System (ADS)

    Zou, Jing; Xie, Zhenghui; Zhan, Chesheng; Qin, Peihua; Sun, Qin; Jia, Binghao; Xia, Jun

    2015-05-01

    In this study, we incorporated a groundwater exploitation scheme into the land surface model CLM3.5 to investigate the effects of the anthropogenic exploitation of groundwater on land surface processes in a river basin. Simulations of the Haihe River Basin in northern China were conducted for the years 1965-2000 using the model. A control simulation without exploitation and three exploitation simulations with different water demands derived from socioeconomic data related to the Basin were conducted. The results showed that groundwater exploitation for human activities resulted in increased wetting and cooling effects at the land surface and reduced groundwater storage. A lowering of the groundwater table, increased upper soil moisture, reduced 2 m air temperature, and enhanced latent heat flux were detected by the end of the simulated period, and the changes at the land surface were related linearly to the water demands. To determine the possible responses of the land surface processes in extreme cases (i.e., in which the exploitation process either continued or ceased), additional hypothetical simulations for the coming 200 years with constant climate forcing were conducted, regardless of changes in climate. The simulations revealed that the local groundwater storage on the plains could not contend with high-intensity exploitation for long if the exploitation process continues at the current rate. Changes attributable to groundwater exploitation reached extreme values and then weakened within decades with the depletion of groundwater resources and the exploitation process will therefore cease. However, if exploitation is stopped completely to allow groundwater to recover, drying and warming effects, such as increased temperature, reduced soil moisture, and reduced total runoff, would occur in the Basin within the early decades of the simulation period. The effects of exploitation will then gradually disappear, and the variables will approach the natural state and stabilize at different rates. Simulations were also conducted for cases in which exploitation either continues or ceases using future climate scenario outputs from a general circulation model. The resulting trends were almost the same as those of the simulations with constant climate forcing, despite differences in the climate data input. Therefore, a balance between slow groundwater restoration and rapid human development of the land must be achieved to maintain a sustainable water resource.

  5. Status of Sandalwood resources in Vanuatu

    Treesearch

    Leonard Bule; Godfrey Daruhi

    1990-01-01

    On eight islands of Vanuatu archipelago, sandalwood stands have been heavily exploited since the late 1800's. Because of the over-exploitation, which worried the Vanuatu Government, a moratorium was imposed in early 1987. The status of the valuable wood and the beginnings of research into one of the country's potential commodities are reviewed.

  6. An Exemplary Lesson on Education for Sustainable Development: A Case in Malaysia

    ERIC Educational Resources Information Center

    Mee, Lee Shok

    2017-01-01

    Malaysian mangrove resources are exploited for woods, fisheries, wildlife, agriculture, and in recent decades for aquaculture and ecotourism. Such exploitations are often unsustainable, particularly when there is permanent change in land usage. In the last four decades, it is estimated that the overall loss in mangrove areas is over 16 percent…

  7. Countermeasure Study on Deep-sea Oil Exploitation in the South China Sea——A Comparison between Deep-sea Oil Exploitation in the South China Sea and the Gulf of Mexico

    NASA Astrophysics Data System (ADS)

    Zhao, Hui; Qiu, Weiting; Qu, Weilu

    2018-02-01

    The unpromising situation of terrestrial oil resources makes the deep-sea oil industry become an important development strategy. The South China Sea has a vast sea area with a wide distribution of oil and gas resources, but there is a phenomenon that exploration and census rates and oil exploitation are low. In order to solve the above problems, this article analyzes the geology, oil and gas exploration and exploration equipment in the South China Sea and the Gulf of Mexico. Comparing the political environment of China and the United States energy industry and the economic environment of oil companies, this article points out China’s deep-sea oil exploration and mining problems that may exist. Finally, the feasibility of oil exploration and exploitation in the South China Sea is put forward, which will provide reference to improve the conditions of oil exploration in the South China Sea and promoting the stable development of China’s oil industry.

  8. Linking water resources to food security through virtual water

    NASA Astrophysics Data System (ADS)

    Tamea, Stefania

    2014-05-01

    The largest use of global freshwater resources is related to food production. While each day we drink about 2 liters of water, we consume (eating) about 4000 liters of ''virtual water'', which represents the freshwater used to produce crop-based and livestock-based food. Considering human water consumption as a whole, most part originates from agriculture (85.8%), and only minor parts come from industry (9.6%) or households (4.6%). These numbers shed light on the great pressure of humanity on global freshwater resources and justify the increasing interest towards this form of environmental impact, usually known as ''water footprint''. Virtual water is a key variable in establishing the nexus between water and food. In fact, water resources used for agricultural production determine local food availability, and impact the international trade of agricultural goods. Trade, in turn, makes food commodities available to nations which are not otherwise self-sufficient, in terms of water resources or food, and it establishes an equilibrium between food demand and production at the global scale. Therefore, food security strongly relies on international food trade, but also on the use of distant and foreign water resources, which need to be acknowledged and investigated. Virtual water embedded in production and international trade follows the fate of food on the trade network, generating virtual flows of great magnitude (e.g., 2800 km3 in 2010) and defining local and global virtual water balances worldwide. The resulting water-food nexus is critical for the societal and economic development, and it has several implications ranging from population dynamics to the competing use of freshwater resources, from dietary guidelines to globalization of trade, from externalization of pollution to policy making and to socio-economic wealth. All these implications represent a great challenge for future research, not only in hydrology but in the many fields related to this interdisciplinary topic. Virtual water and water footprint accounting provide the tools for understanding such implications and to describe, quantify, and investigate the inextricable link existing between water resources and food security.

  9. Trophic Strategies of a Non-Native and a Native Amphibian Species in Shared Ponds

    PubMed Central

    San Sebastián, Olatz; Navarro, Joan; Llorente, Gustavo A.; Richter-Boix, Álex

    2015-01-01

    One of the critical factors for understanding the establishment, success and potential impact on native species of an introduced species is a thorough knowledge of how these species manage trophic resources. Two main trophic strategies for resource acquisition have been described: competition and opportunism. In the present study our objective was to identify the main trophic strategies of the non-native amphibian Discoglossus pictus and its potential trophic impact on the native amphibian Bufo calamita. We determine whether D. pictus exploits similar trophic resources to those exploited by the native B. calamita (competition hypothesis) or alternative resources (opportunistic hypothesis). To this end, we analyzed the stable isotope values of nitrogen and carbon in larvae of both species, in natural ponds and in controlled laboratory conditions. The similarity of the δ15N and δ13C values in the two species coupled with isotopic signal variation according to pond conditions and niche partitioning when they co-occurred indicated dietary competition. Additionally, the non-native species was located at higher levels of trophic niches than the native species and B. calamita suffered an increase in its standard ellipse area when it shared ponds with D. pictus. These results suggest niche displacement of B. calamita to non-preferred resources and greater competitive capacity of D. pictus in field conditions. Moreover, D. pictus showed a broader niche than the native species in all conditions, indicating increased capacity to exploit the diversity of resources; this may indirectly favor its invasiveness. Despite the limitations of this study (derived from potential variability in pond isotopic signals), the results support previous experimental studies. All the studies indicate that D. pictus competes with B. calamita for trophic resources with potential negative effects on the fitness of the latter. PMID:26101880

  10. Fostering the Exploitation of Open Educational Resources

    ERIC Educational Resources Information Center

    Richter, Thomas; Veith, Patrick

    2014-01-01

    The central concept behind Open Educational Resources (OER) is opening up the access to educational resources for stakeholders who are not the usual target user group. This concept must be perceived as innovative because it describes a general economic and social paradigm shift: Education, which formerly was limited to a specific group of…

  11. Maternal Strategies to Access Food Differ by Food Security Status.

    PubMed

    Gorman, Kathleen S; McCurdy, Karen; Kisler, Tiffani; Metallinos-Katsaras, Elizabeth

    2017-01-01

    Household food insecurity is associated with health and behavior risk. Much less is known about how food insecurity is related to strategies that adults use in accessing food: how and where they shop, use of alternative food sources, and their ability to manage resources. To examine how maternal behaviors, including shopping, accessing alternative sources of food, and managing resources, are related to household food security status (HHFSS). Cross-sectional study collecting survey data on HHFSS, shopping behaviors, use of alternative food sources, and managing resources obtained from low-income mothers of preschool-aged children. One hundred sixty-four low-income mothers of young children (55% Hispanic) from two communities in Rhode Island. HHFSS was measured using 10 items from the 18-item Core Food Security Module to assess adult food security. Mothers were surveyed about where, when, and how often they shopped; the strategies they use when shopping; their use of alternative sources of food, including federal, state, and local assistance; and their ability to manage their resources. Analysis of variance and χ 2 analyses assessed the associations between demographic variables, shopping, accessing alternative food sources, and managing resources, and HHFSS. Multivariate logistic regression assessed the associations between HHFSS and maternal demographic variables, food shopping, strategies, alternative sources of food, and ability to manage resources. Maternal age and language spoken at home were significantly associated with HHFSS; food insecurity was 10% more likely among older mothers (adjusted odds ratio [aOR] 1.10, 95% CI 1.03 to 1.17) and 2.5 times more likely among Spanish-speaking households (compared with non-Spanish speaking [aOR 3.57, 95% CI 1.25 to 10.18]). Food insecurity was more likely among mothers reporting more informal strategies (aOR 1.98, 95% CI 1.28 to 3.01; P<0.05) and perceiving greater inability to manage resources (aOR 1.60, 95% CI 1.30 to 1.98; P<0.05). The results suggest that low-income mothers use a variety of strategies to feed their families and that the strategies they use vary by HHFSS. Community nutrition programs and providers will need to consider these strategies when counseling families at risk for food insecurity and provide guidance to minimize the influence on healthy food choices. Copyright © 2017 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

  12. Maternal Strategies to Access Food Differ by Food Security Status

    PubMed Central

    Gorman, Kathleen S.; McCurdy, Karen; Kisler, Tiffani; Metallinos-Katsaras, Elizabeth

    2016-01-01

    Background Household food insecurity is associated with health and behavior risk. Much less is known about how food insecurity is related to strategies that adults use in accessing food: how and where they shop, use of alternative food sources and their ability to manage resources. Objective To examine how maternal behaviors including shopping, accessing alternative sources of food and managing resources are related to household food security status (HHFSS). Design Cross-sectional study collecting survey data on HHFSS, shopping behaviors, use of alternative food sources and managing resources obtained from low income mothers of preschoolers. Participants 164 low-income mothers of young children (55% Hispanic) from two communities in Rhode Island. Measures HHFSS was measured using ten items from the 18-item Core Food Security Module to assess adult food security. Mothers were surveyed about where, when and how often they shopped; the strategies they use when shopping; their use of alternative sources of food including federal, state and local assistance; and their ability to manage their resources. Statistical analyses Analysis of Variance and Chi-square analyses assessed the associations between demographic variables, shopping, accessing alternative food sources and managing resources, and HHFSS. Multivariate logistic regression assessed the associations between HHFSS and maternal demographic variables, food shopping strategies, alternative sources of food and ability to manage resources. Results Maternal age and language spoken at home were significantly associated with HHFSS; food insecurity was 10% more likely among older mothers (AOR=1.10; 95% CI 1.03-1.17) and 2.5 times more likely among Spanish speaking households (compared to non-Spanish speaking-AOR=3.57; 95% CI 1.25-10.18). Food insecurity was more likely among mothers reporting more informal strategies (AOR=1.98; 95% CI 1.28-3.01, p<.05) and perceiving greater inability to manage resources (AOR=1.60; 95% CI 1.30-1.98, p<.05). Conclusions The results suggest that low-income mothers use a variety of strategies in order to feed their families and that the strategies they use vary by HHFSS. Community nutrition programs and providers will need to consider these strategies when counseling families at risk for food insecurity and provide guidance to minimize the impact on healthy food choices. PMID:27614689

  13. Selection of an omnivorous diet by the mangrove tree crab Aratus pisonii in laboratory experiments

    NASA Astrophysics Data System (ADS)

    Erickson, Amy A.; Feller, Ilka C.; Paul, Valerie J.; Kwiatkowski, Lisa M.; Lee, Woody

    2008-02-01

    Observational studies on leaf damage, gut content analyses, and crab behaviour have demonstrated that like numerous other mangrove and salt-marsh generalists, the mangrove tree crab Aratus pisonii feeds on a variety of food resources. This study is the first that experimentally tests feeding preferences of A. pisonii, as well as the first to test experimentally whether chemical composition of food resources is responsible for food selection. Feeding preferences were determined among a variety of plant, algal, and animal resources available in the field both in Florida and Belize, using multiple-choice feeding assays, where male and female crabs simultaneously were offered a variety of food items. To test whether chemistry of food resources was responsible for feeding preferences, chemical extracts of food resources were incorporated in an agar-based artificial food, and used in feeding assays. Results of feeding assays suggest that crabs prefer animal matter from ˜ 2.5 to 13× more than other available resources, including leaves of the red mangrove Rhizophora mangle, which contribute the most to their natural diet. Artificial feeding assays also demonstrated that chemical cues were responsible for selection of animal matter, up to 25× more than other available resources. Non-polar extracts (derived from extraction in 1:1 ethyl actetate:methanol) stimulated feeding the most, suggesting that fatty acids, triglycerides, or sterols may be important for growth, reproduction, or survival. Results for both sexes were similar across most assays. While chemical composition of food resources appears to play some role in selection, this does not discount the potential role of other factors, such as resource availability, competition, predation, or reproductive requirements in influencing feeding preferences. Bioassay-guided fractionation of extracts should aid in determining chemical constituents that play the greatest role in determining feeding preferences.

  14. Palatable Meal Anticipation in Mice

    PubMed Central

    Hsu, Cynthia T.; Patton, Danica F.; Mistlberger, Ralph E.; Steele, Andrew D.

    2010-01-01

    The ability to sense time and anticipate events is a critical skill in nature. Most efforts to understand the neural and molecular mechanisms of anticipatory behavior in rodents rely on daily restricted food access, which induces a robust increase of locomotor activity in anticipation of daily meal time. Interestingly, rats also show increased activity in anticipation of a daily palatable meal even when they have an ample food supply, suggesting a role for brain reward systems in anticipatory behavior, and providing an alternate model by which to study the neurobiology of anticipation in species, such as mice, that are less well adapted to “stuff and starve” feeding schedules. To extend this model to mice, and exploit molecular genetic resources available for that species, we tested the ability of wild-type mice to anticipate a daily palatable meal. We observed that mice with free access to regular chow and limited access to highly palatable snacks of chocolate or “Fruit Crunchies” avidly consumed the snack but did not show anticipatory locomotor activity as measured by running wheels or video-based behavioral analysis. However, male mice receiving a snack of high fat chow did show increased food bin entry prior to access time and a modest increase in activity in the two hours preceding the scheduled meal. Interestingly, female mice did not show anticipation of a daily high fat meal but did show increased activity at scheduled mealtime when that meal was withdrawn. These results indicate that anticipation of a scheduled food reward in mice is behavior, diet, and gender specific. PMID:20941366

  15. Asymmetric competition for nectar between a large nectar thief and a small pollinator: an energetic point of view.

    PubMed

    Padyšáková, Eliška; Okrouhlík, Jan; Brown, Mark; Bartoš, Michael; Janeček, Štěpán

    2017-04-01

    There are two alternative hypotheses related to body size and competition for restricted food sources. The first one supposes that larger animals are superior competitors because of their increased feeding abilities, whereas the second one assumes superiority of smaller animals because of their lower food requirements. We examined the relationship between two unrelated species of different size, drinking technique, energy requirements and roles in plant pollination system, to reveal the features of their competitive interaction and mechanisms enabling their co-existence while utilising the same nectar source. We observed diurnal feeding behaviour of the main pollinator, the carpenter bee Xylocopa caffra and a nectar thief, the northern double-collared sunbird Cinnyris reichenowi on 19 clumps of Hypoestes aristata (Acanthaceae) in Bamenda Highlands, Cameroon. For comparative purpose, we established a simplistic model of daily energy expenditure and daily energy intake by both visitor species assuming that they spend all available daytime feeding on H. aristata. We revealed the energetic gain-expenditure balance of the studied visitor species in relation to diurnal changes in nectar quality and quantity. In general, smaller energy requirements and related ability to utilise smaller resources made the main pollinator X. caffra competitively superior to the larger nectar thief C. reichenowi. Nevertheless, sunbirds are endowed with several mechanisms to reduce asymmetry in exploitative competition, such as the use of nectar resources in times of the day when rivals are inactive, aggressive attacks on carpenter bees while defending the nectar plants, and higher speed of nectar consumption.

  16. Governance conditions for adaptive freshwater management in the Vietnamese Mekong Delta

    NASA Astrophysics Data System (ADS)

    Ha, T. P.; Dieperink, Carel; Dang Tri, Van Pham; Otter, Henriëtte S.; Hoekstra, Piet

    2018-02-01

    The Vietnamese Mekong Delta (VMD) is a region of utmost importance to Vietnam's national food security. However, the availability of required freshwater resources (from both surface and groundwater sources) is currently under great threats due to dry season salinity intrusion, surface water pollution, and over-exploitation of groundwater. Global climate change, sea level rise, and upstream and in situ development activities may worsen the situation. Assuming that adaptive management could be a promising strategy to address the increasingly complex and unpredictable water-related problems in the VMD, we design and apply a framework to identify the extent to which the governance regime in this region exhibits conditions that are likely to promote adaptive freshwater management. Using both primary and secondary data, our analysis reveals that the prospects for adaptive water management in the study area are limited since several conditions were not present. We observe among others limitations in vertical and horizontal integration and public participation, restraints in knowledge and information sharing, inadequate policy development and implementation, and insufficient diversification of financial resources. Following our findings, we conclude the paper with recommendations both for national, regional and local policy interventions and for future research.

  17. Upscaling Arbuscular Mycorrhizal Symbiosis and Related Agroecosystems Services in Smallholder Farming Systems

    PubMed Central

    Oruru, Marjorie Bonareri; Njeru, Ezekiel Mugendi

    2016-01-01

    Smallholder farming systems form unique ecosystems that can protect beneficial soil biota and form an important source of useful genetic resources. They are characterized by high level of agricultural diversity mainly focused on meeting farmers' needs. Unfortunately, these systems often experience poor crop production mainly associated with poor planning and resource scarcity. Soil fertility is among the primary challenges faced by smallholder farmers, which necessitate the need to come up with affordable and innovative ways of replenishing soils. One such way is the use of microbial symbionts such as arbuscular mycorrhizal fungi (AMF), a beneficial group of soil microbiota that form symbiotic associations with majority of cultivated crops and play a vital role in biological soil fertility, plant nutrition, and protection. AMF can be incorporated in smallholder farming systems to help better exploit chemical fertilizers inputs which are often unaffordable to many smallholder farmers. The present review highlights smallholder farming practices that could be innovatively redesigned to increase AMF symbiosis and related agroecosystem services. Indeed, the future of global food security depends on the success of smallholder farming systems, whose crop productivity depends on the services provided by well-functioning ecosystems, including soil fertility. PMID:26942194

  18. Gramene database: navigating plant comparative genomics resources

    USDA-ARS?s Scientific Manuscript database

    Gramene (http://www.gramene.org) is an online, open source, curated resource for plant comparative genomics and pathway analysis designed to support researchers working in plant genomics, breeding, evolutionary biology, system biology, and metabolic engineering. It exploits phylogenetic relationship...

  19. Resources for Teaching HERO: Food Service Occupations in Montana.

    ERIC Educational Resources Information Center

    Parsons, Angelina O.; Harris, Pamela R.

    This resource guide is designed to help home economics teachers in Montana to develop occupational programs for food service. It provides resources that can be used with the "Food Service Occupations in Montana: Scope and Sequence in Wage-Earning Home Economics." The guide contains 13 sections. The first section explains the core…

  20. Exploitation of deep-sea resources: the urgent need to understand the role of high pressure in the toxicity of chemical pollutants to deep-sea organisms.

    PubMed

    Mestre, Nélia C; Calado, Ricardo; Soares, Amadeu M V M

    2014-02-01

    The advent of industrial activities in the deep sea will inevitably expose deep-sea organisms to potentially toxic compounds. Although international regulations require environmental risk assessment prior to exploitation activities, toxicity tests remain focused on shallow-water model species. Moreover, current tests overlook potential synergies that may arise from the interaction of chemicals with natural stressors, such as the high pressures prevailing in the deep sea. As pressure affects chemical reactions and the physiology of marine organisms, it will certainly affect the toxicity of pollutants arising from the exploitation of deep-sea resources. We emphasize the need for environmental risk assessments based on information generated from ecotoxicological trials that mimic, as close as possible, the deep-sea environment, with emphasis to a key environmental factor - high hydrostatic pressure. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Sustainable Resource Development in the Third World. Selected Papers from an International Symposium (Columbus, Ohio, September 1985). Westview Special Studies in Natural Resources and Energy Management.

    ERIC Educational Resources Information Center

    Southgate, Douglas D., Ed.; Disinger, John F., Ed.

    Over time, scientists, technologists, and resource managers in affluent countries have devised and institutionalized methodologies for exploiting and managing natural resources in their own environments with considerable success. In doing so, they have provided models, at least of development and affluence, that the less developed countries seek…

  2. Using Bayesian methods to predict climate impacts on groundwater availability and agricultural production in Punjab, India

    NASA Astrophysics Data System (ADS)

    Russo, T. A.; Devineni, N.; Lall, U.

    2015-12-01

    Lasting success of the Green Revolution in Punjab, India relies on continued availability of local water resources. Supplying primarily rice and wheat for the rest of India, Punjab supports crop irrigation with a canal system and groundwater, which is vastly over-exploited. The detailed data required to physically model future impacts on water supplies agricultural production is not readily available for this region, therefore we use Bayesian methods to estimate hydrologic properties and irrigation requirements for an under-constrained mass balance model. Using measured values of historical precipitation, total canal water delivery, crop yield, and water table elevation, we present a method using a Markov chain Monte Carlo (MCMC) algorithm to solve for a distribution of values for each unknown parameter in a conceptual mass balance model. Due to heterogeneity across the state, and the resolution of input data, we estimate model parameters at the district-scale using spatial pooling. The resulting model is used to predict the impact of precipitation change scenarios on groundwater availability under multiple cropping options. Predicted groundwater declines vary across the state, suggesting that crop selection and water management strategies should be determined at a local scale. This computational method can be applied in data-scarce regions across the world, where water resource management is required to resolve competition between food security and available resources in a changing climate.

  3. Genetic diversity and genomic resources available for the small millet crops to accelerate a New Green Revolution.

    PubMed

    Goron, Travis L; Raizada, Manish N

    2015-01-01

    Small millets are nutrient-rich food sources traditionally grown and consumed by subsistence farmers in Asia and Africa. They include finger millet (Eleusine coracana), foxtail millet (Setaria italica), kodo millet (Paspalum scrobiculatum), proso millet (Panicum miliaceum), barnyard millet (Echinochloa spp.), and little millet (Panicum sumatrense). Local farmers value the small millets for their nutritional and health benefits, tolerance to extreme stress including drought, and ability to grow under low nutrient input conditions, ideal in an era of climate change and steadily depleting natural resources. Little scientific attention has been paid to these crops, hence they have been termed "orphan cereals." Despite this challenge, an advantageous quality of the small millets is that they continue to be grown in remote regions of the world which has preserved their biodiversity, providing breeders with unique alleles for crop improvement. The purpose of this review, first, is to highlight the diverse traits of each small millet species that are valued by farmers and consumers which hold potential for selection, improvement or mechanistic study. For each species, the germplasm, genetic and genomic resources available will then be described as potential tools to exploit this biodiversity. The review will conclude with noting current trends and gaps in the literature and make recommendations on how to better preserve and utilize diversity within these species to accelerate a New Green Revolution for subsistence farmers in Asia and Africa.

  4. Mineral resources of parts of the Departments of Antioquia and Caldas, Zone II, Colombia

    USGS Publications Warehouse

    Hall, R.B.; Feininger, Tomas; Barrero, L.; Dario, Rico H.; ,; Alvarez, A.

    1970-01-01

    The mineral resources of an area of 40,000 sq km, principally in the Department of Antioquia, but including small parts of the Departments of Caldas, C6rdoba, Risaralda, and Tolima, were investigated during the period 1964-68. The area is designated Zone II by the Colombian Inventario Minero Nacional(lMN). The geology of approximately 45 percent of this area, or 18,000 sq km, has been mapped by IMN. Zone II has been a gold producer for centuries, and still produces 75 percent of Colombia's gold. Silver is recovered as a byproduct. Ferruginous laterites have been investigated as potential sources of iron ore but are not commercially exploitable. Nickeliferous laterite on serpentinite near Ure in the extreme northwest corner of the Zone is potentially exploitable, although less promising than similar laterites at Cerro Matoso, north of the Zone boundary. Known deposits of mercury, chromium, manganese, and copper are small and have limited economic potentia1. Cement raw materials are important among nonmetallic resources, and four companies are engaged in the manufacture of portland cement. The eastern half of Zone II contains large carbonate rock reserves, but poor accessibility is a handicap to greater development at present. Dolomite near Amalfi is quarried for the glass-making and other industries. Clay saprolite is abundant and widely used in making brick and tiles in backyard kilns. Kaolin of good quality near La Union is used by the ceramic industry. Subbituminous coal beds of Tertiary are an important resource in the western part of the zone and have good potential for greater development. Aggregate materials for construction are varied and abundant. Deposits of sodic feldspar, talc, decorative stone, and silica are exploited on a small scale. Chrysotils asbestos deposits north of Campamento are being developed to supply fiber for Colombia's thriving asbestos-cement industry, which is presently dependent upon imported fiber. Wollastonite and andalusite are potential resources not exploitable now.

  5. An assessment of food safety information provision for UK chemotherapy patients to reduce the risk of foodborne infection.

    PubMed

    Evans, E W; Redmond, E C

    2017-12-01

    Given the increased risk of foodborne infection to cancer patients receiving chemotherapy treatment, and the risk of listeriosis reportedly five-times greater to this immunocompromised patient group, there is a need to ensure the implementation of domestic food safety practices among chemotherapy patients and their family caregivers. However, information regarding the adequacy of resources to inform and enable patients to implement domestic food safety practices to reduce the risk of foodborne infection is limited. Consequently, this study aimed to evaluate the provision of food safety information available to UK chemotherapy patients. In-depth semi-structured interviews and content analysis of online patient information resources. Interviews with patients and family caregivers (n = 15) were conducted to explore food-related experiences during chemotherapy treatment. Online food-related information resources for chemotherapy patients (n = 45) were obtained from 35 of 154 National Health Service chemotherapy providers in England, Scotland, and Wales, the Department of Health (DoH) and three of 184 identified UK cancer charities. Identified food-related information resources were reviewed using a content-analysis approach to assess the inclusion of food safety information for chemotherapy patients. In-depth interviews established that many patients indicated awareness of immunosuppression during treatment. Although patients reported practicing caution to reduce the risk of communicable diseases by avoiding crowded spaces/public transport, food safety was reported to be of minimal concern during treatment and the risk of foodborne infection was often underestimated. The review of online food-related patient information resources established that many resources failed to highlight the increased risk of foodborne infection and emphasize the importance of food safety for patients during chemotherapy treatment. Considerable information gaps exist, particularly in relation to listeriosis prevention practices. Cumulatively, information was inconsistent, insufficient, and varied between resources. The study has identified the need for an effective, standardized food safety resource specifically targeting chemotherapy patients and family caregivers. Such intervention is essential to assist efforts in reducing the risks associated with foodborne infection among chemotherapy patients. Copyright © 2017 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

  6. A Data Analysis Toolbox for Modeling the Global Food-Energy-Water Nexus

    NASA Astrophysics Data System (ADS)

    AghaKouchak, A.; Sadegh, M.; Mallakpour, I.

    2017-12-01

    Water, Food and energy systems are highly interconnected. More than seventy percent of global water resource is used for food production. Water withdrawal, purification, and transfer systems are energy intensive. Furthermore, energy generation strongly depends on water availability. Therefore, considering the interactions in the nexus of water, food and energy is crucial for sustainable management of available resources. In this presentation, we introduce a user-friendly data analysis toolbox that mines the available global data on food, energy and water, and analyzes their interactions. This toolbox provides estimates of water footprint for a wide range of food types in different countries and also approximates the required energy and water resources. The toolbox also provides estimates of the corresponding emissions and biofuel production of different crops. In summary, this toolbox allows evaluating dependencies of the food, energy, and water systems at the country scale. We present global analysis of the interactions between water, food and energy from different perspectives including efficiency and diversity of resources use.

  7. "Founder crops" v. wild plants: Assessing the plant-based diet of the last hunter-gatherers in southwest Asia

    NASA Astrophysics Data System (ADS)

    Arranz-Otaegui, Amaia; González Carretero, Lara; Roe, Joe; Richter, Tobias

    2018-04-01

    The Natufian culture (c. 14.6-11.5 ka cal. BP) represents the last hunter-gatherer society that inhabited southwest Asia before the development of plant food production. It has long been suggested that Natufians based their economy on the exploitation of the wild ancestors of the Neolithic "founder crops", and that these hunter-gatherers were therefore on the "threshold to agriculture". In this work we review the available data on Natufian plant exploitation and we report new archaeobotanical evidence from Shubayqa 1, a Natufian site located in northeastern Jordan (14.6-11.5 ka cal. BP). Shubayqa 1 has produced an exceptionally large plant assemblage, including direct evidence for the continuous exploitation of club-rush tubers (often regarded as "missing foods") and other wild plants, which were probably used as food, fuel and building materials. Taking together this data we evaluate the composition of archaeobotanical assemblages (plant macroremains) from the Natufian to the Early Pre-Pottery Neolithic B (EPPNB). Natufian assemblages comprise large proportions of non-founder plant species (>90% on average), amongst which sedges, small-seeded grasses and legumes, and fruits and nuts predominate. During the Pre-Pottery Neolithic, in particular the EPPNB, the presence of "founder crops" increases dramatically and constitute up to c. 42% of the archaeobotanical assemblages on average. Our results suggest that plant exploitation strategies during the Natufian were very different from those attested during subsequent Neolithic periods. We argue that historically driven interpretations of the archaeological record have over-emphasized the role of the wild ancestors of domesticated crops previous to the emergence of agriculture.

  8. Lithic Landscapes: Early Human Impact from Stone Tool Production on the Central Saharan Environment

    PubMed Central

    Foley, Robert A.; Lahr, Marta Mirazón

    2015-01-01

    Humans have had a major impact on the environment. This has been particularly intense in the last millennium but has been noticeable since the development of food production and the associated higher population densities in the last 10,000 years. The use of fire and over-exploitation of large mammals has also been recognized as having an effect on the world’s ecology, going back perhaps 100,000 years or more. Here we report on an earlier anthropogenic environmental change. The use of stone tools, which dates back over 2.5 million years, and the subsequent evolution of a technologically-dependent lineage required the exploitation of very large quantities of rock. However, measures of the impact of hominin stone exploitation are rare and inherently difficult. The Messak Settafet, a sandstone massif in the Central Sahara (Libya), is littered with Pleistocene stone tools on an unprecedented scale and is, in effect, a man-made landscape. Surveys showed that parts of the Messak Settafet have as much as 75 lithics per square metre and that this fractured debris is a dominant element of the environment. The type of stone tools—Acheulean and Middle Stone Age—indicates that extensive stone tool manufacture occurred over the last half million years or more. The lithic-strewn pavement created by this ancient stone tool manufacture possibly represents the earliest human environmental impact at a landscape scale and is an example of anthropogenic change. The nature of the lithics and inferred age may suggest that hominins other than modern humans were capable of unintentionally modifying their environment. The scale of debris also indicates the significance of stone as a critical resource for hominins and so provides insights into a novel evolutionary ecology. PMID:25760999

  9. A systematic review of wild grass exploitation in relation to emerging cereal cultivation throughout the Epipalaeolithic and aceramic Neolithic of the Fertile Crescent

    PubMed Central

    Riehl, Simone; Zeidi, Mohsen; Conard, Nicholas J.

    2018-01-01

    The present study investigates the occurrence of wild grasses at Epipalaeolithic and aceramic Neolithic sites in the Near East in order to assess their role in subsistence economies alongside the emergence of cereal cultivation. We use Chogha Golan in the foothills of the central Zagros Mountains (ca. 11.7–9.6 ka cal. BP) as a case study, where the archaeobotanical data suggest the frequent exploitation of a complex of wild grasses for almost 2,000 years. Domesticated emmer replaced these wild grasses as the major food resources towards the end of occupation at the site (ca. 9.8 ka cal. BP). We discuss possible implications of this development and conclude that the traditional concept of pre-domestication cultivation seems unsuited for explaining the patterns from Chogha Golan. These data are in good accordance with the overall picture in the Zagros Mountains, where wild grasses were routinely gathered throughout the early Holocene. In contrast, wild grasses were gradually replaced by wild cereals in the Levantine corridor since the end of the Pleistocene. However, several sites located in this region provide evidence for a continuous exploitation of wild grasses alongside emerging cereal cultivation and most of these taxa were part of the earliest segetal floras that evolved with the appearance of domestic cereals throughout the 11th millennium cal. BP. Some sites contemporary to the Pre-Pottery Neolithic B still provide evidence for the usage of wild grasses, which possibly reflects the utilization of edible arable weeds and continuous gathering of wild grasses by more mobile groups. PMID:29293519

  10. Surface processing: existing and potential applications of ultraviolet light.

    PubMed

    Manzocco, Lara; Nicoli, Maria Cristina

    2015-01-01

    Solid foods represent optimal matrices for ultraviolet processing with effects well beyond nonthermal surface disinfection. UV radiation favors hormetic response in plant tissues and degradation of toxic compound on the product surface. Photoinduced reactions can also provide unexplored possibilities to steer structure and functionality of food biopolymers. The possibility to extensively exploit this technology will depend on availability of robust information about efficacious processing conditions and adequate strategies to completely and homogeneously process food surface.

  11. Lost water and nitrogen resources due to EU consumer food waste

    NASA Astrophysics Data System (ADS)

    Vanham, D.; Bouraoui, F.; Leip, A.; Grizzetti, B.; Bidoglio, G.

    2015-08-01

    The European Parliament recently called for urgent measures to halve food waste in the EU, where consumers are responsible for a major part of total waste along the food supply chain. Due to a lack of data on national food waste statistics, uncertainty in (consumer) waste quantities (and the resulting associated quantities of natural resources) is very high, but has never been previously assessed in studies for the EU. Here we quantify: (1) EU consumer food waste, and (2) associated natural resources required for its production, in term of water and nitrogen, as well as estimating the uncertainty of these values. Total EU consumer food waste averages 123 (min 55-max 190) kg/capita annually (kg/cap/yr), i.e. 16% (min 7-max 24%) of all food reaching consumers. Almost 80%, i.e. 97 (min 45-max 153) kg/cap/yr is avoidable food waste, which is edible food not consumed. We have calculated the water and nitrogen (N) resources associated with avoidable food waste. The associated blue water footprint (WF) (the consumption of surface and groundwater resources) averages 27 litre per capita per day (min 13-max 40 l/cap/d), which slightly exceeds the total blue consumptive EU municipal water use. The associated green WF (consumptive rainwater use) is 294 (min 127-max 449) l/cap/d, equivalent to the total green consumptive water use for crop production in Spain. The nitrogen (N) contained in avoidable food waste averages 0.68 (min 0.29-max 1.08) kg/cap/yr. The food production N footprint (any remaining N used in the food production process) averages 2.74 (min 1.02-max 4.65) kg/cap/yr, equivalent to the use of mineral fertiliser by the UK and Germany combined. Among all the food product groups wasted, meat accounts for the highest amounts of water and N resources, followed by wasted cereals. The results of this study provide essential insights and information on sustainable consumption and resource efficiency for both EU policies and EU consumers.

  12. Usage and Recall of the Food Stamp Office Resource Kit (FSORK) by Food Stamp Applicants in 4 California Counties

    ERIC Educational Resources Information Center

    Ghirardelli, Alyssa; Linares, Amanda; Fong, Amy

    2011-01-01

    Objective: To evaluate recall and usage of the Food Stamp Office Resource Kit (FSORK), a set of nutrition education materials designed for use in food stamp offices. Design: Client intercept exit surveys, an environmental scan, and individual observations of clients in the food stamp office. Setting: Four food stamp offices in California.…

  13. Consumption processes and food web structure in the Columbia River Estuary

    NASA Astrophysics Data System (ADS)

    Simenstad, Charles A.; Small, Lawrence F.; David McIntire, C.

    Consumption processes at several trophic levels tend to coverage in the central (estuarine-mixing) region of the Columbia River estuary, where living and dentrital food resources are entrained within the energy null of the turbidity maximum zone. Primary consumers in this region are generalist and omnivorous feeders, capable of exploiting both autotrophic and heterotrophic food web pathways. In the presence of higher standing stocks of their prey resources, feeding by secondary and tertiary consumers is also concentrated, or more effective, in the estuarine mixing region of the estuary. During the 1980-1981 studies of the estuary, total consumer (metazoan) production averaged 5.5g C m -2 within the estuary. Of the estimated 15 x 10 3mt Cyy -1 attributed to primary consumption in the water column, 83% was the result of suspension-feeding pelagic zooplankton. In comparison to grazing on phytoplankton, it was estimated that approximately 84% of primary consumption in the water column was based on suspended detritus and, presumably, associated microbiota. Endemic primary,consumers, principally epibenthic crustaceans such as the calanoid copepod Eurytemora affinis, the harpacticoid copepod Scottolana canadensis, and the crangonid shrimp Crangon franciscorum, accounted for a high proportion of the consumption of suspended particles. Wertland herbivores inhabiting the estuary's extensive marshes, on the other hand, were estimated to account for only 2 to 17% of total estuarine primary consumption. Trophic linkages to secondary and tertiary consumers were more evenly apportioned among pelagic fishes, motile macroinvertebrates, and benthic infauna. High, comparatively unknown fluxes of migratory or wide-ranging tertiary consumers, such as piscivorous birds, seals and sea lions, made estimation of their annual consumption rates in the estuary highly tenuous. The physical processes of mixing and stratification, sediments accretion and erosion, and salinity intrusion appear to be the fundamental determinants of consumption processes in the Columbia River estuary, and perhaps in other similarly energetic estuarine systems, by promoting concentrations of consumers in low-energy habitats such as the turbidity maximum and peripheral bays.

  14. Flock Foraging Efficiency in Relation to Food Sensing Ability and Distribution: a Simulation Study

    NASA Astrophysics Data System (ADS)

    Lee, Sang-Hee

    2013-08-01

    Flocking may be an advantageous strategy for acquiring food resources. The degree of advantage is related to two factors: the ability of flock members to detect food resources and patterns of food distribution in the environment. To understand foraging efficiency as a function of these factors, I constructed a two-dimensional (2D) flocking model incorporating the two factors. At the start of the simulation, food particles were heterogeneously distributed. The heterogeneity, H, was characterized as a value ranging from 0.0 to 1.0. For each flock member, food sensing ability was defined by two variables: sensing distance, R and sensing angle, θ. Foraging efficiency of a flock was defined as the time, τ, required for a flock to consume all the available food resources. Simulation results showed that flock foraging is most efficient when individuals had an intermediate sensing ability (R = 60), but decreased for low (R < 60) and high (R > 60) sensing ability. When R > 60, patterns in foraging efficiency with increasing sensing distance and food resource aggregation were less consistent. This inconsistency was due to instability of the flock and a higher rate of individuals failing to capture target food resources. In addition, I briefly discuss the benefits obtained by foraging in flocks from an evolutionary perspective.

  15. On the status, reproductive biology and management of fruit bats of Yap, Micronesia

    Treesearch

    Marjorie V. C. Falanruw

    1988-01-01

    Traditional exploitation of fruit bats of Yap is limited, however commercial exploitation greatly reduced populations until they were protected indefinitely. There will be continued need to manage this resource. This paper is based on field work conducted while Yap's bats were intensively hunted. Data from field work is augmented with information from...

  16. [Impacts of hydroelectric cascade exploitation on river ecosystem and landscape: a review].

    PubMed

    Yang, Kun; Deng, Xi; Li, Xue-Ling; Wen, Ping

    2011-05-01

    Hydroelectric cascade exploitation, one of the major ways for exploiting water resources and developing hydropower, not only satisfies the needs of various national economic sectors, but also promotes the socio-economic sustainable development of river basin. unavoidable anthropogenic impacts on the entire basin ecosystem. Based on the process of hydroelectric cascade exploitation and the ecological characteristics of river basins, this paper reviewed the major impacts of hydroelectric cascade exploitation on dam-area ecosystems, river reservoirs micro-climate, riparian ecosystems, river aquatic ecosystems, wetlands, and river landscapes. Some prospects for future research were offered, e.g., strengthening the research of chain reactions and cumulative effects of ecological factors affected by hydroelectric cascade exploitation, intensifying the study of positive and negative ecological effects under the dam networks and their joint operations, and improving the research of successional development and stability of basin ecosystems at different temporal and spatial scales.

  17. Body size and the division of niche space: food and predation differentially shape the distribution of Serengeti grazers.

    PubMed

    Hopcraft, J Grant C; Anderson, T Michael; Pérez-Vila, Saleta; Mayemba, Emilian; Olff, Han

    2012-01-01

    1. Theory predicts that small grazers are regulated by the digestive quality of grass, while large grazers extract sufficient nutrients from low-quality forage and are regulated by its abundance instead. In addition, predation potentially affects populations of small grazers more than large grazers, because predators have difficulty capturing and handling large prey. 2. We analyse the spatial distribution of five grazer species of different body size in relation to gradients of food availability and predation risk. Specifically, we investigate how the quality of grass, the abundance of grass biomass and the associated risks of predation affect the habitat use of small, intermediate and large savanna grazers at a landscape level. 3. Resource selection functions of five mammalian grazer species surveyed over a 21-year period in Serengeti are calculated using logistic regressions. Variables included in the analyses are grass nitrogen, rainfall, topographic wetness index, woody cover, drainage lines, landscape curvature, water and human habitation. Structural equation modelling (SEM) is used to aggregate predictor variables into 'composites' representing food quality, food abundance and predation risk. Subsequently, SEM is used to investigate species' habitat use, defined as their recurrence in 5 × 5 km cells across repeated censuses. 4. The distribution of small grazers is constrained by predation and food quality, whereas the distribution of large grazers is relatively unconstrained. The distribution of the largest grazer (African buffalo) is primarily associated with forage abundance but not predation risk, while the distributions of the smallest grazers (Thomson's gazelle and Grant's gazelle) are associated with high grass quality and negatively with the risk of predation. The distributions of intermediate sized grazers (Coke's hartebeest and topi) suggest they optimize access to grass biomass of sufficient quality in relatively predator-safe areas. 5. The results illustrate how top-down (vegetation-mediated predation risk) and bottom-up factors (biomass and nutrient content of vegetation) predictably contribute to the division of niche space for herbivores that vary in body size. Furthermore, diverse grazing assemblages are composed of herbivores of many body sizes (rather than similar body sizes), because these herbivores best exploit the resources of different habitat types. © 2011 The Authors. Journal of Animal Ecology © 2011 British Ecological Society.

  18. The energetics of low browsing in sauropods.

    PubMed

    Ruxton, Graeme D; Wilkinson, David M

    2011-10-23

    It has recently been argued that the probable high cost of travel for sauropod dinosaurs would have made exploiting high forage energetically attractive, if this reduced the need to travel between food patches. This argument was supported by simple calculations. Here, we take a similar approach to evaluate the energetics of foraging close to the ground. We predict that small extensions of the neck beyond the minimum required for the mouth to reach the ground bring substantial energetic savings. Each increment of length brings a further saving, but the sizes of such benefits decrease with increasing neck length. However, the observed neck length of around 9 m for Brachiosaurus (for example) is predicted to reduce the overall cost of foraging by 80 per cent, compared with a minimally necked individual. We argue that the long neck of the sauropods may have been under positive selection for low foraging (instead of, or as well as, exploitation of high foraging), if this long neck allowed a greater area of food to be exploited from a given position and thus reduced the energetically expensive movement of the whole animal.

  19. Analysis of Water Resource Utilization Potential for Jiangsu Coastal Area ' in Nantong City

    NASA Astrophysics Data System (ADS)

    Ren, Li; Liu, Jin-Tao; Ni, Jian-Jun

    2015-04-01

    Along with the advance of the growth of population and social economy, requirements for water quality and quantity in coastal areas is getting higher and higher, but due to the uneven distribution of rainfall years and water exploitation, use and management level, the influence of the shortage of water resources is increasingly prominent, seriously restricting the social and economic sustainable development in this region. Accordingly, water resource utilization potential in Jiangsu coastal region is vital for water security in the region. Taking Nantong City as the study area, the regional water resources development and utilization status were evaluated. In this paper, the meaning of water resources, water resources development and utilization, and water resources development and utilization of the three stages of concepts such as system were discussed. Then the development and utilization of regional water resource evaluation were carried out, and the significance of regional society, economy, resources and environment and its development status quo of water resources were exploited. According to conditions and area source, an evaluation index system for development and utilization of water resources of Nantong was built up. The index layer was composed of 16 indicators. In this study, analytic hierarchy process (AHP) was used to determine of weights of indicators at all levels in the index system. Multistage fuzzy comprehensive evaluation model was selected to evaluate the water resources development and utilization status of Nantong, and then water resource utilization potential of Nantong was analyzed.

  20. Overestimating resource value and its effects on fighting decisions.

    PubMed

    Dugatkin, Lee Alan; Dugatkin, Aaron David

    2011-01-01

    Much work in behavioral ecology has shown that animals fight over resources such as food, and that they make strategic decisions about when to engage in such fights. Here, we examine the evolution of one, heretofore unexamined, component of that strategic decision about whether to fight for a resource. We present the results of a computer simulation that examined the evolution of over- or underestimating the value of a resource (food) as a function of an individual's current hunger level. In our model, animals fought for food when they perceived their current food level to be below the mean for the environment. We considered seven strategies for estimating food value: 1) always underestimate food value, 2) always overestimate food value, 3) never over- or underestimate food value, 4) overestimate food value when hungry, 5) underestimate food value when hungry, 6) overestimate food value when relatively satiated, and 7) underestimate food value when relatively satiated. We first competed all seven strategies against each other when they began at approximately equal frequencies. In such a competition, two strategies--"always overestimate food value," and "overestimate food value when hungry"--were very successful. We next competed each of these strategies against the default strategy of "never over- or underestimate," when the default strategy was set at 99% of the population. Again, the strategies of "always overestimate food value" and "overestimate food value when hungry" fared well. Our results suggest that overestimating food value when deciding whether to fight should be favored by natural selection.

  1. Geothermal resources: exploration and exploitation. A bibliography

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

    Not Available

    This comprehensive bibliography contains 5476 citations of foreign and domestic research reports, journal articles, patents, conference proceedings, and books concerned with the exploration and exploitation of geothermal resources. The coverage dates back as far as useful references could be obtained and extends through June 1976. References are arranged in broad subject categories and are made up of complete bibliographic citations. These are followed by a listing of subject descriptors used to describe the subject content of each reference. Four indexes are included: Corporate, Personal Author, Subject, and Report Number. Also included is a list of journals from which articles weremore » selected. (LBS)« less

  2. The largest renewable, easily exploitable, and economically sustainable energy resource

    NASA Astrophysics Data System (ADS)

    Abbate, Giancarlo; Saraceno, Eugenio

    2018-02-01

    Sun, the ultimate energy resource of our planet, transfers energy to the Earth at an average power of 23,000 TW. Earth surface can be regarded as a huge panel transforming solar energy into a more convenient mechanical form, the wind. Since millennia wind is recognized as an exploitable form of energy and it is common knowledge that the higher you go, the stronger the winds flow. To go high is difficult; however Bill Gates cites high wind among possible energy miracles in the near future. Public awareness of this possible miracle is still missing, but today's technology is ready for it.

  3. Getting the Most out of PubChem for Virtual Screening

    PubMed Central

    Kim, Sunghwan

    2016-01-01

    Introduction With the emergence of the “big data” era, the biomedical research community has great interest in exploiting publicly available chemical information for drug discovery. PubChem is an example of public databases that provide a large amount of chemical information free of charge. Areas covered This article provides an overview of how PubChem’s data, tools, and services can be used for virtual screening and reviews recent publications that discuss important aspects of exploiting PubChem for drug discovery. Expert opinion PubChem offers comprehensive chemical information useful for drug discovery. It also provides multiple programmatic access routes, which are essential to build automated virtual screening pipelines that exploit PubChem data. In addition, PubChemRDF allows users to download PubChem data and load them into a local computing facility, facilitating data integration between PubChem and other resources. PubChem resources have been used in many studies for developing bioactivity and toxicity prediction models, discovering polypharmacologic (multi-target) ligands, and identifying new macromolecule targets of compounds (for drug-repurposing or off-target side effect prediction). These studies demonstrate the usefulness of PubChem as a key resource for computer-aided drug discovery and related area. PMID:27454129

  4. Lunar material resources: An overview

    NASA Technical Reports Server (NTRS)

    Carter, James L.

    1992-01-01

    The analysis of returned lunar samples and a comparison of the physical and chemical processes operating on the Moon and on the Earth provide a basis for predicting both the possible types of material resources (especially minerals and rocks) and the physical characteristics of ore deposits potentially available on the Moon. The lack of free water on the Moon eliminates the classes of ore deposits that are most exploitable on Earth; namely, (1) hydrothermal, (2) secondary mobilization and enrichment, (3) precipitation from a body of water, and (4) placer. The types of lunar materials available for exploitation are whole rocks and their contained minerals, regolith, fumarolic and vapor deposits, and nonlunar materials, including solar wind implantations. Early exploitation of lunar material resources will be primarily the use of regolith materials for bulk shielding; the extraction from regolith fines of igneous minerals such as plagioclase feldspars and ilmenite for the production of oxygen, structural metals, and water; and possibly the separation from regolith fines of solar-wind-implanted volatiles. The only element, compound, or mineral, that by itself has been identified as having the economic potential for mining, processing, and return to Earth is helium-3.

  5. The History of Makassan Trepang Fishing and Trade

    PubMed Central

    Schwerdtner Máñez, Kathleen; Ferse, Sebastian C. A.

    2010-01-01

    The Malayan term trepang describes a variety of edible holothurians commonly known as sea cucumbers. Although found in temperate and tropical marine waters all over the world, the centre of species diversity and abundance are the shallow coastal waters of Island Southeast Asia. For at least 300 years, trepang has been a highly priced commodity in the Chinese market. Originally, its fishing and trade was a specialized business, centred on the town of Makassar in South Sulawesi (Indonesia). The rise of trepang fishing in the 17th century added valuable export merchandize to the rich shallow seas surrounding the islands of Southeast Asia. This enabled local communities to become part of large trading networks and greatly supported their economic development. In this article, we follow Makassan trepang fishing and trading from its beginning until the industrialization of the fishery and worldwide depletion of sea cucumbers in the 20th century. Thereby, we identify a number of characteristics which trepang fishing shares with the exploitation of other marine resources, including (1) a strong influence of international markets, (2) the role of patron-client relationships which heavily influence the resource selection, and (3) the roving-bandit-syndrome, where fishermen exploit local stocks of valuable resources until they are depleted, and then move to another area. We suggest that understanding the similarities and differences between historical and recent exploitation of marine resources is an important step towards effective management solutions. PMID:20613871

  6. The history of Makassan trepang fishing and trade.

    PubMed

    Schwerdtner Máñez, Kathleen; Ferse, Sebastian C A

    2010-06-29

    The Malayan term trepang describes a variety of edible holothurians commonly known as sea cucumbers. Although found in temperate and tropical marine waters all over the world, the centre of species diversity and abundance are the shallow coastal waters of Island Southeast Asia. For at least 300 years, trepang has been a highly priced commodity in the Chinese market. Originally, its fishing and trade was a specialized business, centred on the town of Makassar in South Sulawesi (Indonesia). The rise of trepang fishing in the 17(th) century added valuable export merchandize to the rich shallow seas surrounding the islands of Southeast Asia. This enabled local communities to become part of large trading networks and greatly supported their economic development. In this article, we follow Makassan trepang fishing and trading from its beginning until the industrialization of the fishery and worldwide depletion of sea cucumbers in the 20(th) century. Thereby, we identify a number of characteristics which trepang fishing shares with the exploitation of other marine resources, including (1) a strong influence of international markets, (2) the role of patron-client relationships which heavily influence the resource selection, and (3) the roving-bandit-syndrome, where fishermen exploit local stocks of valuable resources until they are depleted, and then move to another area. We suggest that understanding the similarities and differences between historical and recent exploitation of marine resources is an important step towards effective management solutions.

  7. Potential and attainable food production and food security in different regions

    PubMed Central

    Vries, F. W. T. Penning de; Rabbinge, R.; Groot, J. J. R.

    1997-01-01

    Growing prosperity in the South is accompanied by human diets that will claim more natural resources per capita. This reality, combined with growing populations, may raise the global demand for food crops two- to four-fold within two generations. Considering the large volume of natural resources and potential crop yields, it seems that this demand can be met smoothly. However, this is a fallacy for the following reasons. (i) Geographic regions differ widely in their potential food security: policy choices for agricultural use of natural resources are limited in Asia. For example, to ensure national self-sufficiency and food security, most of the suitable land (China) and nearly all of the surface water (India) are needed. Degradation restricts options further. (ii) The attainable level of agricultural production depends also on socio-economic conditions. Extensive poverty keeps the attainable food production too low to achieve food security, even when the yield gap is wide, as in Africa. (iii) Bio-energy, non-food crops and nature compete with food crops for natural resources. Global and regional food security are attainable, but only with major efforts. Strategies to achieve alternative aims will be discussed.

  8. Spatial distribution patterns of sheep following manipulation of feeding motivation and food availability.

    PubMed

    Freire, R; Swain, D L; Friend, M A

    2012-05-01

    We hypothesised that (i) increased feeding motivation will cause sheep to move further apart as a result of individuals trying to find food and (ii) in conditions of high food availability, sheep will move less and show greater social attraction. The effects of both feeding motivation and food availability on spatial distribution was examined in eight groups of food-deprived (high feeding motivation) and satiated (low feeding motivation) sheep in good or poor food resource plots in a 2 × 2 design. Distance travelled was assessed using Global Positioning System collars, grazing time using scan sampling and social cohesion using proximity collars that record the number and duration of encounters within 4 m. Food-deprived sheep in the good-resource plots grazed the most, whereas satiated sheep in the poor-resource plots grazed the least (P = 0.004). Food deprivation had no significant effect on the number or duration of encounters and feeding motivation appeared to have little effect on spatial distribution. Contrary to expectation, sheep had more encounters (P = 0.04) of a longer total duration (P = 0.02) in poor-resource plots than in good-resource plots, indicating that sheep were showing more social cohesion if food was scarce. Our findings suggest that when food is scarce, animals may come together in an attempt to share information on food availability. However, when a highly preferred food is abundant and well dispersed, they may move apart in order to maximise the intake. It is concluded that the particular details of our experiment, namely the even distribution or absence of a highly preferred food, affected spatial distribution patterns as sheep tried to find this food and maximise the intake.

  9. Characteristics and consumer acceptance of healthier meat and meat product formulations-a review.

    PubMed

    Hathwar, Swapna C; Rai, Amit Kumar; Modi, Vinod Kumar; Narayan, Bhaskar

    2012-12-01

    Awareness of health and nutrition has led to the development of "functional foods" which is a new approach to achieve healthier status thus reducing the risk of diseases. Meat has been highly exploited as a functional ingredient/food in recent years wherein meat has either been modified or incorporated into non meat products. Changing consumer demand has influenced the market for all types of meat. The development and marketing the functional foods can be, however, very challenging compared to the foods that conventionally have a high health image. This review gives the overall perception about importance of using meat/meat products as a functional food.

  10. Non-energy resources, Connecticut and Rhode Island coastal waters

    USGS Publications Warehouse

    Neff, N.F.; Lewis, R.S.

    1989-01-01

    Cores collected from Long Island Sound, Connecticut, were used to establish control on the geologic framework of the area. Lithologic and stratigraphic analyses verified the presence of the following units: (1) Cretaceous coastal plain, (2) Pleistocene glacial till, (3) late Pleistocene glacial lake, (4) late Pleistocene glacial outwash, and (5) Holocene fluvial, estuarine and marine deposits. Cores collected in Block Island Sound, Rhode Island, were obtained from inferred, relict shoreline features and were analyzed for heavy mineral content. Concentrations ranged from 0.3 to 3.4%; no significant downcore changes were found. The results indicated that surficial sediments in areas of high-velocity tidal flow yield greater amounts of heavy minerals than do inferred placer deposits. During the second phase of the program of study, Connecticut and Rhode Island pooled resources to develop a study plan for the comprehensive quantification of all non-energy resources in the adjacent waters of the states. A literature and data survey was conducted to assess the occurrence, extent, and accessibility of these resources. Sand and gravel and heavy minerals were found in concentrations offering potential for resource exploitation. Constraints on exploitation include (1) water depth restrictions for the protection of shellfish beds and public beaches, (2) fishing activities, (3) military, commercial, and fishing vessel traffic, (4) seafloor cable routes and (5) dump sites. Deposits composed of Pleistocene glacial sediments and/or Holocene marine sediments in regions of little or no user conflict were identified as sites potentially suitable for resource exploitation. The study plan stated additional data needs (geophysical profiling and vibracore sampling) at these sites. Subsequent to these recommendations, high-resolution seismic profiles and sidescan sonographs were obtained from these sites. Seismic stratigraphic analyses confirm the presence of extensive deposits of potential economic value. ?? 1989.

  11. Health on impulse: when low self-control promotes healthy food choices.

    PubMed

    Salmon, Stefanie J; Fennis, Bob M; de Ridder, Denise T D; Adriaanse, Marieke A; de Vet, Emely

    2014-02-01

    Food choices are often made mindlessly, when individuals are not able or willing to exert self-control. Under low self-control, individuals have difficulties to resist palatable but unhealthy food products. In contrast to previous research aiming to foster healthy choices by promoting high self-control, this study exploits situations of low self-control, by strategically using the tendency under these conditions to rely on heuristics (simple decision rules) as quick guides to action. More specifically, the authors associated healthy food products with the social proof heuristic (i.e., normative cues that convey majority endorsement for those products). One hundred seventy-seven students (119 men), with an average age of 20.47 years (SD = 2.25) participated in the experiment. This study used a 2 (low vs. high self-control) × 2 (social proof vs. no heuristic) × 2 (trade-off vs. control choice) design, with the latter as within-subjects factor. The dependent variable was the number of healthy food choices in a food-choice task. In line with previous studies, people made fewer healthy food choices under low self-control. However, this negative effect of low self-control on food choice was reversed when the healthy option was associated with the social proof heuristic. In that case, people made more healthy choices under conditions of low self-control. Low self-control may be even more beneficial for healthy food choices than high self-control in the presence of a heuristic. Exploiting situations of low self-control is a new and promising method to promote health on impulse. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  12. Warming and Resource Availability Shift Food Web Structure and Metabolism

    PubMed Central

    O'Connor, Mary I.; Piehler, Michael F.; Leech, Dina M.; Anton, Andrea; Bruno, John F.

    2009-01-01

    Climate change disrupts ecological systems in many ways. Many documented responses depend on species' life histories, contributing to the view that climate change effects are important but difficult to characterize generally. However, systematic variation in metabolic effects of temperature across trophic levels suggests that warming may lead to predictable shifts in food web structure and productivity. We experimentally tested the effects of warming on food web structure and productivity under two resource supply scenarios. Consistent with predictions based on universal metabolic responses to temperature, we found that warming strengthened consumer control of primary production when resources were augmented. Warming shifted food web structure and reduced total biomass despite increases in primary productivity in a marine food web. In contrast, at lower resource levels, food web production was constrained at all temperatures. These results demonstrate that small temperature changes could dramatically shift food web dynamics and provide a general, species-independent mechanism for ecological response to environmental temperature change. PMID:19707271

  13. Diets of swift foxes (Vulpes velox) in continuous and fragmented prairie in Northwestern Texas

    USGS Publications Warehouse

    Kamler, J.F.; Ballard, W.B.; Wallace, M.C.; Gipson, P.S.

    2007-01-01

    Distribution of the swift fox (Vulpes velox) has declined dramatically since the 1800s, and suggested causes of this decline are habitat fragmentation and transformation due to agricultural expansion. However, impacts of fragmentation and human-altered habitats on swift foxes still are not well understood. To better understand what effects these factors have on diets of swift foxes, scats were collected in northwestern Texas at two study sites, one of continuous native prairie and one representing fragmented native prairie interspersed with agricultural and fields in the Conservation Reserve Program. Leporids, a potential food source, were surveyed seasonally on both sites. Diets of swift foxes differed between sites; insects were consumed more on continuous prairie, whereas mammals, birds, and crops were consumed more on fragmented prairie. Size of populations of leporids were 2-3 times higher on fragmented prairie, and swift foxes responded by consuming more leporids on fragmented (11.1% frequency occurrence) than continuous (3.8%) prairie. Dietary diversity was greater on fragmented prairie during both years of the study. Differences in diets between sites suggested that the swift fox is an adaptable and opportunistic feeder, able to exploit a variety of food resources, probably in relation to availability of food. We suggest that compared to continuous native prairie, fragmented prairie can offer swift foxes a more diverse prey base, at least within the mosaic of native prairie, agricultural, and fields that are in the Conservation Reserve Program.

  14. Understanding and engineering beneficial plant–microbe interactions: plant growth promotion in energy crops

    PubMed Central

    Farrar, Kerrie; Bryant, David; Cope-Selby, Naomi

    2014-01-01

    Plant production systems globally must be optimized to produce stable high yields from limited land under changing and variable climates. Demands for food, animal feed, and feedstocks for bioenergy and biorefining applications, are increasing with population growth, urbanization and affluence. Low-input, sustainable, alternatives to petrochemical-derived fertilizers and pesticides are required to reduce input costs and maintain or increase yields, with potential biological solutions having an important role to play. In contrast to crops that have been bred for food, many bioenergy crops are largely undomesticated, and so there is an opportunity to harness beneficial plant–microbe relationships which may have been inadvertently lost through intensive crop breeding. Plant–microbe interactions span a wide range of relationships in which one or both of the organisms may have a beneficial, neutral or negative effect on the other partner. A relatively small number of beneficial plant–microbe interactions are well understood and already exploited; however, others remain understudied and represent an untapped reservoir for optimizing plant production. There may be near-term applications for bacterial strains as microbial biopesticides and biofertilizers to increase biomass yield from energy crops grown on land unsuitable for food production. Longer term aims involve the design of synthetic genetic circuits within and between the host and microbes to optimize plant production. A highly exciting prospect is that endosymbionts comprise a unique resource of reduced complexity microbial genomes with adaptive traits of great interest for a wide variety of applications. PMID:25431199

  15. Factors influencing eating a varied diet in old age.

    PubMed

    Dean, Moira; Raats, Monique M; Grunert, Klaus G; Lumbers, Margaret

    2009-12-01

    To investigate the influences of resources and food-related goals on the variety of food choice among older people. A questionnaire-based survey in eight European countries: Poland, Portugal, United Kingdom, Germany, Sweden, Denmark, Italy and Spain. Participants (n 3200) were above 65 years of age and living in their own homes. The samples were quota samples, eight groups of fifty in each country, based on gender, age and living circumstances, reflecting the diversity of each of the national populations based on education, income and urbanization of living environment. Hierarchical multiple regression analysis showed that income, health status, access to a car and living arrangement affected the level of dietary variety. The perceived level of different food-related resources impacted the consumption of a varied diet over and above actual resource levels. Food-related goals contributed to variety of food intake that was not accounted for by the amount of material resources possessed or the social and other resources perceived to be possessed. Older people's variety of food intake depended on material resources (e.g. monthly income, access to a car, living arrangement, physical and mental health). However, in addition to these variables, the way older people perceived other resources, such as their level of appetite, their food knowledge, their perception of the distance to the shops, access to high-quality products, having better kitchen facilities, access to good service providers and support from friends and neighbours, all contributed to how varied a diet they ate.

  16. Carbon isotope ratios of human tooth enamel record the evidence of terrestrial resource consumption during the Jomon period, Japan.

    PubMed

    Kusaka, Soichiro; Uno, Kevin T; Nakano, Takanori; Nakatsukasa, Masato; Cerling, Thure E

    2015-08-17

    Archaeological remains strongly suggest that the Holocene Japanese hunter-gatherers, the Jomon people, utilized terrestrial plants as their primary food source. However, carbon and nitrogen isotope analysis of bone collagen indicates that they primarily exploited marine resources. We hypothesize that this inconsistency stems from the route of protein synthesis and the different proportions of protein-derived carbon in tooth enamel versus bone collagen. Carbon isotope ratios from bone collagen reflect that of dietary protein and may provide a biased signal of diet, whereas isotope ratios from tooth enamel reflect the integrated diet from all macronutrients (carbohydrates, lipids, and proteins). In order to evaluate the differences in inferred diet between the archaeological evidence and bone collagen isotope data, this study investigated carbon isotopes in Jomon tooth enamel from four coastal sites of the Middle to Late-Final Jomon period (5,000-2,300 years BP). Carbon isotope ratios of human teeth are as depleted as coeval terrestrial mammals, suggesting that C 3 plants and terrestrial mammals were major dietary resources for the Jomon people. Dietary dependence on marine resources calculated from enamel was significantly lower than that calculated from bone collagen. The discrepancy in isotopic ratios between enamel and collagen and the nitrogen isotope ratio in collagen shows a negative correlation on individual and population levels, suggesting diets with variable proportions of terrestrial and marine resources. This study highlights the usefulness of coupling tooth enamel and bone collagen in carbon isotopic studies to reconstruct prehistoric human diet. Am J Phys Anthropol, 2015. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

  17. Learning to Control Advanced Life Support Systems

    NASA Technical Reports Server (NTRS)

    Subramanian, Devika

    2004-01-01

    Advanced life support systems have many interacting processes and limited resources. Controlling and optimizing advanced life support systems presents unique challenges. In particular, advanced life support systems are nonlinear coupled dynamical systems and it is difficult for humans to take all interactions into account to design an effective control strategy. In this project. we developed several reinforcement learning controllers that actively explore the space of possible control strategies, guided by rewards from a user specified long term objective function. We evaluated these controllers using a discrete event simulation of an advanced life support system. This simulation, called BioSim, designed by Nasa scientists David Kortenkamp and Scott Bell has multiple, interacting life support modules including crew, food production, air revitalization, water recovery, solid waste incineration and power. They are implemented in a consumer/producer relationship in which certain modules produce resources that are consumed by other modules. Stores hold resources between modules. Control of this simulation is via adjusting flows of resources between modules and into/out of stores. We developed adaptive algorithms that control the flow of resources in BioSim. Our learning algorithms discovered several ingenious strategies for maximizing mission length by controlling the air and water recycling systems as well as crop planting schedules. By exploiting non-linearities in the overall system dynamics, the learned controllers easily out- performed controllers written by human experts. In sum, we accomplished three goals. We (1) developed foundations for learning models of coupled dynamical systems by active exploration of the state space, (2) developed and tested algorithms that learn to efficiently control air and water recycling processes as well as crop scheduling in Biosim, and (3) developed an understanding of the role machine learning in designing control systems for advanced life support.

  18. Mental imagery interventions reduce subsequent food intake only when self-regulatory resources are available.

    PubMed

    Missbach, Benjamin; Florack, Arnd; Weissmann, Lukas; König, Jürgen

    2014-01-01

    Research has shown that imagining food consumption leads to food-specific habituation effects. In the present research, we replicated these effects and further examined whether the depletion of self-regulatory resources would reduce the habituation effects of imagined food consumption. Since self-regulatory resources have been shown to reduce habituation effects during the perception of emotional stimuli, we expected a reduction in habituation effects from imagined food consumption when self-regulatory resources were depleted. In Study 1, we replicated habituation effects as a response to imagining gummy bear consumption with a high (36) and medium number (18) of repetitions in a camouflaged taste test. Participants imagining gummy bear intake showed decreased food intake compared with participants who imagined putting a coin into a laundry machine. The number of repetitions did not significantly moderate the observed habituation effect. In Study 2, we investigated whether self-regulatory depletion would impede habituation effects evoked by the imagination of walnut consumption. Participants in a depleted state did not show a reduction in food intake after imagining walnut intake compared with participants in a non-depleted state. We discuss directions for future research and processes that might underlie the observed moderating effect of self-regulatory resources.

  19. Frontiers of the food-energy-water trilemma: Sri Lanka as a microcosm of tradeoffs

    NASA Astrophysics Data System (ADS)

    Perrone, Debra; Hornberger, George

    2016-01-01

    Food, energy, and water are three critical resources for humanity. As climate variability, population growth, and lifestyle changes amplify the stress placed on each of the resources, the interrelationships among food, energy, and water systems become more pronounced. Political conflict, social and cultural norms, and spatial and temporal distribution of the resources add additional layers of complexity. It is in this context that the significance of understanding the impacts of water scarcity on the decisions around food and energy productions has emerged. Our work establishes tradeoff frontiers (TFs) as a method useful in illustrating the system-level tradeoffs between allocating water for food and water for energy. This paper illustrates how TFs can be used to (1) show how scarcity in water resources affects the tradeoffs between food and energy and (2) explore the political and social constraints that can move production away from what is feasible technically. We use Sri Lanka, a country where water resources are variable both in space and time and a country with relatively self-contained energy and agricultural sectors, as a microcosm of the food security, energy security, and water security trilemma. Nevertheless, our application of tradeoff frontiers is applicable widely to other systems.

  20. American Farm Bureau Foundation for Agriculture - Homepage

    Science.gov Websites

    Literacy? What We Do Resources Sustainable Agriculture Food and Farm Facts Free Resources & Lesson Agriculture Food and Farm Facts Free Resources & Lesson Plans Bringing Biotech to Life Learn About Beef Farm For Teachers Free Resources Outreach Team Grow your Ag Literacy Impact Career Spotlight

  1. The role of food-security solutions in the protection of natural resources and environment of developing countries.

    PubMed

    Lashgarara, Farhad; Mirdamadi, Seyyed Mehdi; Hosseini, Seyyed Jamal Farajollah; Chizari, Mohammad

    2008-10-01

    The majority of the countries of the world, especially developing countries, face environmental problems. Limitations of basic resources (water and soil) and population growth have been the cause of these environmental problems that countries are confronted with. Developing countries have numerous problems, including destruction of forests, vegetable and animal species, and pollution of the environment. Damage to natural resources and the environment can influence the food-security situation. One of the main millennium development goals (MDGs) is protection of the environment and people's health. This cannot obtained unless there is ensured food security. Food security has been defined as a situation when all people, at all times, have physical and economic access to sufficient, safe, and nutritious food needed to maintain a healthy and active life. At the same time, with ensured food security, we can hope to protect the natural resources and environment. The methodology used is descriptive-analytical, and its main purpose is determining the importance and role of food-security solutions in the reduction of environmental hazards and improvement of natural resources and the environmental situation in developing countries. Therefore, some of the most important food-security solutions that can play an important role in this relation were discussed, including conventional research-based technology, biotechnology, information and communication technologies (ICTs), alternative energy sources, and food irradiation.

  2. Contextualizing Embodied Resources in Global Food Trade

    NASA Astrophysics Data System (ADS)

    MacDonald, G. K.; Brauman, K. A.; Sun, S.; West, P. C.; Carlson, K. M.; Cassidy, E. S.; Gerber, J. S.; Ray, D. K.

    2014-12-01

    Trade in agricultural commodities has created increasingly complex linkages between resource use and food supplies across national borders. Understanding the degree to which food production and consumption relies on trade is vital to understanding how to sustainably meet growing food demands across scales. We use detailed bilateral trade statistics and data on agricultural management to examine the land use and water consumption embodied in agricultural trade, which we relate to basic nutritional indicators to show how trade contributes to food availability worldwide. Agricultural trade carries enough calories to provide >1.7 billion people a basic diet each year. We identify key commodities and producer-consumer relationships that disproportionately contribute to embodied resource use and flows of food nutrition at the global scale. For example, just 15 disproportionately large soybean trades comprised ~10% the total harvested area embodied in export production. We conclude by framing these results in terms of the fraction of each country's food production and consumption that is linked to international trade. These findings help to characterize how countries allocate resources to domestic versus foreign food demand.

  3. Clinical-Community Partnerships to Identify Patients With Food Insecurity and Address Food Needs

    PubMed Central

    Siegel, Karen R.; Calhoun, Holly; Kim, Sonia A.; Garcia, Sandra P.; Hoeting, Natalie M.; Harris, Diane M.; Khan, Laura Kettel; Smith, Bryce; Blanck, Heidi M.; Barnett, Kevin; Haddix, Anne C.

    2017-01-01

    Introduction More than 42 million people in the United States are food insecure. Although some health care entities are addressing food insecurity among patients because of associations with disease risk and management, little is known about the components of these initiatives. Methods The Systematic Screening and Assessment Method was used to conduct a landscape assessment of US health care entity–based programs that screen patients for food insecurity and connect them with food resources. A network of food insecurity researchers, experts, and practitioners identified 57 programs, 22 of which met the inclusion criteria of being health care entities that 1) screen patients for food insecurity, 2) link patients to food resources, and 3) target patients including adults aged 50 years or older (a focus of this assessment). Data on key features of each program were abstracted from documentation and telephone interviews. Results Most programs (n = 13) focus on patients with chronic disease, and most (n = 12) partner with food banks. Common interventions include referrals to or a list of food resources (n = 19), case managers who navigate patients to resources (n = 15), assistance with federal benefit applications (n = 14), patient education and skill building (n = 13), and distribution of fruit and vegetable vouchers redeemable at farmers markets (n = 8). Most programs (n = 14) routinely screen all patients. Conclusion The programs reviewed use various strategies to screen patients, including older adults, for food insecurity and to connect them to food resources. Research is needed on program effectiveness in improving patient outcomes. Such evidence can be used to inform the investments of potential stakeholders, including health care entities, community organizations, and insurers. PMID:29144894

  4. Semi-supervised word polarity identification in resource-lean languages.

    PubMed

    Dehdarbehbahani, Iman; Shakery, Azadeh; Faili, Heshaam

    2014-10-01

    Sentiment words, as fundamental constitutive parts of subjective sentences, have a substantial effect on analysis of opinions, emotions and beliefs. Most of the proposed methods for identifying the semantic orientations of words exploit rich linguistic resources such as WordNet, subjectivity corpora, or polarity tagged words. Shortage of such linguistic resources in resource-lean languages affects the performance of word polarity identification in these languages. In this paper, we present a method which exploits a language with rich subjectivity analysis resources (English) to identify the polarity of words in a resource-lean foreign language. The English WordNet and a sparse foreign WordNet infrastructure are used to create a heterogeneous, multilingual and weighted semantic network. To identify the semantic orientation of foreign words, a random walk based method is applied to the semantic network along with a set of automatically weighted English positive and negative seeds. In a post-processing phase, synonym and antonym relations in the foreign WordNet are used to filter the random walk results. Our experiments on English and Persian languages show that the proposed method can outperform state-of-the-art word polarity identification methods in both languages. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. A Diagnostic Assessment of Evolutionary Multiobjective Optimization for Water Resources Systems

    NASA Astrophysics Data System (ADS)

    Reed, P.; Hadka, D.; Herman, J.; Kasprzyk, J.; Kollat, J.

    2012-04-01

    This study contributes a rigorous diagnostic assessment of state-of-the-art multiobjective evolutionary algorithms (MOEAs) and highlights key advances that the water resources field can exploit to better discover the critical tradeoffs constraining our systems. This study provides the most comprehensive diagnostic assessment of MOEAs for water resources to date, exploiting more than 100,000 MOEA runs and trillions of design evaluations. The diagnostic assessment measures the effectiveness, efficiency, reliability, and controllability of ten benchmark MOEAs for a representative suite of water resources applications addressing rainfall-runoff calibration, long-term groundwater monitoring (LTM), and risk-based water supply portfolio planning. The suite of problems encompasses a range of challenging problem properties including (1) many-objective formulations with 4 or more objectives, (2) multi-modality (or false optima), (3) nonlinearity, (4) discreteness, (5) severe constraints, (6) stochastic objectives, and (7) non-separability (also called epistasis). The applications are representative of the dominant problem classes that have shaped the history of MOEAs in water resources and that will be dominant foci in the future. Recommendations are provided for which modern MOEAs should serve as tools and benchmarks in the future water resources literature.

  6. Utilization potential evaluation of plant resources in the dry-hot valley of Jinsha River

    NASA Astrophysics Data System (ADS)

    Xi, Rong; Xu, Naizhong; Liu, Shengxiang; Ren, Tingyan

    2017-08-01

    Plant resources in the dry-hot valley of Jinsha River are endemic to a class of district. The article adopts the analytic hierarchy process method to evaluate the exploitation and utilization potential of plant resources of thirty typical plant resources on the basis of their characteristics in the dry-hot valley of Jinsha River, which provide scientific evidence for quantitative evaluation of regional plant resources, and we also suggest pathways offering protection and development.

  7. Food metabolomics: from farm to human.

    PubMed

    Kim, Sooah; Kim, Jungyeon; Yun, Eun Ju; Kim, Kyoung Heon

    2016-02-01

    Metabolomics, one of the latest components in the suite of systems biology, has been used to understand the metabolism and physiology of living systems, including microorganisms, plants, animals and humans. Food metabolomics can be defined as the application of metabolomics in food systems, including food resources, food processing and diet for humans. The study of food metabolomics has increased gradually in the recent years, because food systems are directly related to nutrition and human health. This review describes the recent trends and applications of metabolomics to food systems, from farm to human, including food resource production, industrial food processing and food intake by humans. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Risk of Performance Decrement and Crew Illness Due to an Inadequate Food System

    NASA Technical Reports Server (NTRS)

    Douglas, Grace L.; Cooper, Maya; Bermudez-Aguirre, Daniela; Sirmons, Takiyah

    2016-01-01

    NASA is preparing for long duration manned missions beyond low-Earth orbit that will be challenged in several ways, including long-term exposure to the space environment, impacts to crew physiological and psychological health, limited resources, and no resupply. The food system is one of the most significant daily factors that can be altered to improve human health, and performance during space exploration. Therefore, the paramount importance of determining the methods, technologies, and requirements to provide a safe, nutritious, and acceptable food system that promotes crew health and performance cannot be underestimated. The processed and prepackaged food system is the main source of nutrition to the crew, therefore significant losses in nutrition, either through degradation of nutrients during processing and storage or inadequate food intake due to low acceptability, variety, or usability, may significantly compromise the crew's health and performance. Shelf life studies indicate that key nutrients and quality factors in many space foods degrade to concerning levels within three years, suggesting that food system will not meet the nutrition and acceptability requirements of a long duration mission beyond low-Earth orbit. Likewise, mass and volume evaluations indicate that the current food system is a significant resource burden. Alternative provisioning strategies, such as inclusion of bioregenerative foods, are challenged with resource requirements, and food safety and scarcity concerns. Ensuring provisioning of an adequate food system relies not only upon determining technologies, and requirements for nutrition, quality, and safety, but upon establishing a food system that will support nutritional adequacy, even with individual crew preference and self-selection. In short, the space food system is challenged to maintain safety, nutrition, and acceptability for all phases of an exploration mission within resource constraints. This document presents the evidence for the Risk of Performance Decrement and Crew Illness Due to an Inadequate Food System and the gaps in relation to exploration, as identified by the NASA Human Research Program (HRP). The research reviewed here indicates strategies to establish methods, technologies, and requirements that increase food stability, support adequate nutrition, quality, and variety, enable supplementation with grow-pick-and-eat salad crops, ensure safety, and reduce resource use. Obtaining the evidence to establish an adequate food system is essential, as the resources allocated to the food system may be defined based on the data relating nutritional stability and food quality requirements to crew performance and health.

  9. Community Level Stressors and Their Impacts on Food Contamination

    EPA Science Inventory

    Research is needed to understand a community’s food resources, utilization of those resources, and how the built and natural environment impact access to resources and potential chemical exposures. This research will identify stressors, relationships between those stressors...

  10. The Polar Ocean in a Warming Planet: Understanding for managing a unique resource of the Humankind

    NASA Astrophysics Data System (ADS)

    Azzolini, R.; Campus, P.; Weber, J.

    2012-04-01

    There is no doubt that changes in the Polar Regions are of great significance at the global level, such as having far-reaching effects on atmospheric and ocean circulation. Changes in ocean currents, temperature conditions, ice cover and reduction of permafrost regions are having impacts on marine and terrestrial ecosystems in the Arctic Regions of Europe and Northern Hemisphere. Human activity is putting pressure on the environment in these regions; maritime transport between Europe and Asia through the northern sea route and accessibility conditions to hidden Arctic resources as well as new technologies of exploitation will have a significant impact on the marine environment, on the living resources and on the regional social organization and needs. There are still unresolved issues related to national claims on continental shelf and sea areas that involve international law; in these respects science can provide crucial elements for supporting political agreements. Such scenarios will present new opportunities for economic activities, but also risks which will result in new demands for marine management, monitoring systems, emergency response systems, search and rescue services as well as closer international cooperation. It will also require the development of an international regime based on the improvement of the present regulations on exploration, accessibility, exploitation and liability. Dialogue and international agreements based on scientific evidences and foresight are key elements for finding solutions. On the opposite hemisphere, the ocean surrounding Antarctica plays a primary role in all global climatic processes, through the annual sea ice evolution, the circum-Antarctic circulation driving the exchange of heat between low and high latitudes and the atmospheric circulation, through the density bottom currents that affect the global Thermohaline circulation (THC), and the biogeochemical cycles that have peculiar characteristics in the icy Antarctic waters. Besides this, the marine living resources and the reservoirs of energy and bio-chemical resources (e.g. gas hydrates, bio-prospecting) have a growing strategic importance in the global economy. The Antarctic Ocean, due to its isolation and extreme climatic conditions, has always been an area of international cooperation and technological challenges in support of scientific progress. In this scenario, the rapid environmental changes and the need of humankind for new and alternative reservoirs of food and energy to be exploited play a crucial role in understanding and managing the Polar oceans. The newly emerging opportunities and associated emerging threats for Arctic people increase the number of policy areas in which EU involvement is relevant and necessary. In order to gain insight into the this complex scenario and into the needs in terms of research programmes and infrastructures, policy and education to manage it, the European Polar Board launched an initiative in Polar marine science. The ESF/EPB marine initiative is intended to focus on various aspect of the Polar marine environment and to indicate a strategy focused on innovative scientific and technological topics, capable of combining together different research capacities as well as political, economic and strategic objectives, toward goals of economic and social interest. Therefore, it is based on a wide and multidisciplinary participation.

  11. Assessment of Agricultural Water Management in Punjab, India using Bayesian Methods

    NASA Astrophysics Data System (ADS)

    Russo, T. A.; Devineni, N.; Lall, U.; Sidhu, R.

    2013-12-01

    The success of the Green Revolution in Punjab, India is threatened by the declining water table (approx. 1 m/yr). Punjab, a major agricultural supplier for the rest of India, supports irrigation with a canal system and groundwater, which is vastly over-exploited. Groundwater development in many districts is greater than 200% the annual recharge rate. The hydrologic data required to complete a mass-balance model are not available for this region, therefore we use Bayesian methods to estimate hydrologic properties and irrigation requirements. Using the known values of precipitation, total canal water delivery, crop yield, and water table elevation, we solve for each unknown parameter (often a coefficient) using a Markov chain Monte Carlo (MCMC) algorithm. Results provide regional estimates of irrigation requirements and groundwater recharge rates under observed climate conditions (1972 to 2002). Model results are used to estimate future water availability and demand to help inform agriculture management decisions under projected climate conditions. We find that changing cropping patterns for the region can maintain food production while balancing groundwater pumping with natural recharge. This computational method can be applied in data-scarce regions across the world, where agricultural water management is required to resolve competition between food security and changing resource availability.

  12. The evolution of halophytes, glycophytes and crops, and its implications for food security under saline conditions.

    PubMed

    Cheeseman, John M

    2015-04-01

    The effective development of salt tolerant crops requires an understanding that the evolution of halophytes, glycophytes and our major grain crops has involved significantly different processes. Halophytes (and other edaphic endemics) generally arose through colonization of habitats in severe disequilibrium by pre-adapted individuals, rather than by gradual adaptation from populations of 'glycophytes'. Glycophytes, by contrast, occur in low sodium ecosystems, where sodium was and is the major limiting nutrient in herbivore diets, suggesting that their evolution reflects the fact that low sodium individuals experienced lower herbivory and had higher fitness. For domestication/evolution of crop plants, the selective pressure was human imposed and involved humans co-opting functions of defense and reproductive security. Unintended consequences of this included loss of tolerance to various stresses and loss of the genetic variability needed to correct that. Understanding, combining and manipulating all three modes of evolution are now critical to the development of salt tolerant crops, particularly those that will offer food security in countries with few economic resources and limited infrastructure. Such efforts will require exploiting the genetic structures of recently evolved halophytes, the genetic variability of model plants, and endemic halophytes and 'minor' crops that already exist. © 2014 The Author. New Phytologist © 2014 New Phytologist Trust.

  13. Reading the 'Net--Books in Cyberspace.

    ERIC Educational Resources Information Center

    Foster, Janet

    1999-01-01

    Discusses electronic text collections, bookstores on the Web, reader advisories, cyber book reviews, and resources for librarians explaining how to locate online reading materials. Suggests that librarians can exploit online book resources to complement current collection-development strategies or use them as virtual reader's advisories. Cites 17…

  14. A comparative assessment of the response of three fruit fly species (Diptera: Tephritidae) to a spinosad-based bait: Effect of ammonium acetate, female age, and protein hunger

    USDA-ARS?s Scientific Manuscript database

    Ammonia-releasing substances are known to play an important role in fruit fly (Diptera: Tephritidae) attraction to food sources and this information has been exploited for the development of effective synthetic food-based lures and insecticidal baits. In field studies conducted in Hawaii, we examine...

  15. Water Resource Monitoring Based n EO Data: Gained Experience After 10 Years of Dragon Programme over the Yangtze River Reaches: From ERS 1 to Sentinel 1 and from MERIS to HJ1 and Pleiades

    NASA Astrophysics Data System (ADS)

    Yesou, Herve; Huber, Claire; Huang, Shifeng; Studer, Mathias; Lai, Xijun; Chen, Xiaoling; Daillet, Sylviane

    2014-11-01

    Water resources monitoring from space is an application of remote sensing under full development, with arriving satellite such as the Sentinels, and of course the development of inland applications of altimetry and the future mission as SWOT. Since 10 years within the framework of the DRAGON ESA MOST programme, a monitoring of Chines major fresh water lakes, Poyang and Dongting lakes on Yangtze reaches, is realized exploiting large source of EO data. Thanks to EO data archive exploitation, the covered period starts in 2000 up to 2014, over these two core lakes, whereas, since a 2012, a similar approach is carried over the small lakes of Anhui Province. A key question is how to access to convenient satellite data with sufficient resource to insure a high temporal frequency, ie ideally with about 10 days of revisit. An opportunistic approach was followed in order to insure this data access thanks to a large ESA support, accessing Envisat and ESA TPM, as well Chinese data. From 2004 to April 2012, ENVISAT Medium resolution products, MERIS and ASAR WSM data, were the core of the monitoring system. Since the lost of Envisat, the data exploited moved from MR to HR (20-30 m), thanks to the access to large volume of HJ1 images in 2012 and 2014, as well as coverage CSK data (30m) thanks agreement with ASI. The assimilation of these data is a fine preparation for the future exploitation of Sentinel1 and 2 dataset. Furthermore a first Sentinel data have been exploited, less than 45 after satellite launch. In addition on most sensitive areas, such as the Poyang Lake natural Reserve (Jiangxi Pr) and Shenjing Lake (Anhui Prov.) a unique set of VHR data, Pleiades, Kompsat, have been exploited. The expect strategy for the coming months and years will be in a first period, the jointly exploitation of Sentinel 1 data if the Chinese areas are rapidly integrated within the Sentinel 1 acquisition scheme, jointly with the Chinese HJ1AB data. In a second time HJ1AB data would be substituted by the higher resolved and rich in term of radiometry Sentinel2.

  16. Water Resource Monitoring Based on EO Data: Gained Experience After 10 Years of Dragon Programme over the Yangtze Middle Reaches: From ERS 1 to Sentinel 1 and from MERIS to HJ1 and Pleiades

    NASA Astrophysics Data System (ADS)

    Yesou, Herve; Huber, Claire; Huang, Shifeng; Studer, Mathais; Lai, Xijun; Chen, Xiaoling; Daillet, Sylviane

    2014-11-01

    Water resources monitoring from space is an application of remote sensing under full development, with arriving satellite such as the Sentinels, and of course the development of inland applications of altimetry and the future mission as SWOT. Since 10 years within the framework of the DRAGON ESA MOST programme, a monitoring of Chines major fresh water lakes, Poyang and Dongting lakes on Yangtze reaches, is realized exploiting large source of EO data. Thanks to EO data archive exploitation, the covered period starts in 2000 up to 2014, over these two core lakes, whereas, since a 2012, a similar approach is carried over the small lakes of Anhui Province. A key question is how to access to convenient satellite data with sufficient resource to insure a high temporal frequency, ie ideally with about 10 days of revisit. An opportunistic approach was followed in order to insure this data access thanks to a large ESA support, accessing Envisat and ESA TPM, as well Chinese data. From 2004 to April 2012, ENVISAT Medium resolution products, MERIS and ASAR WSM data, were the core of the monitoring system. Since the lost of Envisat, the data exploited moved from MR to HR (20-30 m), thanks to the access to large volume of HJ1 images in 2012 and 2014, as well as coverage CSK data (30m) thanks agreement with ASI. The assimilation of these data is a fine preparation for the future exploitation of Sentinel1 and 2 dataset. Furthermore a first Sentinel data have been exploited, less than 45 after satellite launch. In addition on most sensitive areas, such as the Poyang Lake natural Reserve (Jiangxi Pr) and Shenjing Lake (Anhui Prov.) a unique set of VHR data, Pleiades, Kompsat, have been exploited. The expect strategy for the coming months and years will be in a first period, the jointly exploitation of Sentinel 1 data if the Chinese areas are rapidly integrated within the Sentinel 1 acquisition scheme, jointly with the Chinese HJ1AB data. In a second time HJ1AB data would be substituted by the higher resolved and rich in term of radiometry Sentinel2.

  17. Consumption stereotypes and impression management: how you are what you eat.

    PubMed

    Vartanian, Lenny R; Herman, C Peter; Polivy, Janet

    2007-05-01

    Consumption stereotypes refer to judgments about others based on their food intake. We review the empirical research on stereotypes based on what and how much people eat. The characteristics stereotypically associated with food intake pertain to domains ranging from gender roles and social appeal to health and weight. For example, people who eat "healthy" foods and smaller meals are seen as more feminine; conversely, those who eat "unhealthy" foods and larger meals are seen as more masculine. We further discuss how these stereotypes can be exploited by the eater to convey a particular impression (e.g., femininity, social appeal). Finally, we discuss the ways in which using food intake as an impression-management tactic can lead to chronic food restriction and unhealthy eating habits.

  18. Putting desire on a budget: dopamine and energy expenditure, reconciling reward and resources

    PubMed Central

    Beeler, Jeff A.; Frazier, Cristianne R. M.; Zhuang, Xiaoxi

    2012-01-01

    Accumulating evidence indicates integration of dopamine function with metabolic signals, highlighting a potential role for dopamine in energy balance, frequently construed as modulating reward in response to homeostatic state. Though its precise role remains controversial, the reward perspective of dopamine has dominated investigation of motivational disorders, including obesity. In the hypothesis outlined here, we suggest instead that the primary role of dopamine in behavior is to modulate activity to adapt behavioral energy expenditure to the prevailing environmental energy conditions, with the role of dopamine in reward and motivated behaviors derived from its primary role in energy balance. Dopamine has long been known to modulate activity, exemplified by psychostimulants that act via dopamine. More recently, there has been nascent investigation into the role of dopamine in modulating voluntary activity, with some investigators suggesting that dopamine may serve as a final common pathway that couples energy sensing to regulated voluntary energy expenditure. We suggest that interposed between input from both the internal and external world, dopamine modulates behavioral energy expenditure along two axes: a conserve-expend axis that regulates generalized activity and an explore-exploit axes that regulates the degree to which reward value biases the distribution of activity. In this view, increased dopamine does not promote consumption of tasty food. Instead increased dopamine promotes energy expenditure and exploration while decreased dopamine favors energy conservation and exploitation. This hypothesis provides a mechanistic interpretation to an apparent paradox: the well-established role of dopamine in food seeking and the findings that low dopaminergic functions are associated with obesity. Our hypothesis provides an alternative perspective on the role of dopamine in obesity and reinterprets the “reward deficiency hypothesis” as a perceived energy deficit. We propose that dopamine, by facilitating energy expenditure, should be protective against obesity. We suggest the apparent failure of this protective mechanism in Western societies with high prevalence of obesity arises as a consequence of sedentary lifestyles that thwart energy expenditure. PMID:22833718

  19. Use of alternative plant resources by common marmosets (Callithrix jacchus) in the semi-arid caatinga scrub forests of northeastern Brazil.

    PubMed

    Amora, Tacyana Duarte; Beltrão-Mendes, Raone; Ferrari, Stephen F

    2013-04-01

    The common marmoset (Callithrix jacchus) is amply distributed in the Brazilian Northeast, but little is known of its ecology in the semi-arid Caatinga scrublands. The present study provides the first detailed data on the composition of the diet of C. jacchus in Caatinga ecosystems, derived from observations at four sites in the state of Sergipe. While exudate sources were gouged at all four sites in a manner typical of the species, fruit was the principal component of the diet at the main study site during most months, and a number of unusual items were eaten, including leaves, and the reproductive parts of cacti and bromeliads. These plants are rarely recorded in marmoset diets, but are common in caatinga habitats. Leaves were ingested during 5 of the 8 months monitored at the main study site, reaching 39.74% of the diet in 1 month, and appeared to be an alternative fallback food to plant exudates during periods when fruit was scarce. Three species of cactus provided both flowers and fruits, while the terrestrial bromeliad, Encholirium spectabile, provided nectar (30.81% of the diet in November). Approximately half of the plant species (and three families) identified in this study had not been recorded previously in the diet of Callithrix. Overall, the data suggest that, while the marmosets exploit the same types of plant foods in the Caatinga, the resource base is quite distinct from that of the Atlantic Forest. Other differences, such as relatively small groups and large home ranges, may contribute to divergent ecological patterns, which require more systematic investigation. Am. J. Primatol. 75:333-341, 2013. © 2012 Wiley Periodicals, Inc. © 2012 Wiley Periodicals, Inc.

  20. Using a Water Balance Model to Bound Potential Irrigation Development in the Upper Blue Nile Basin

    NASA Astrophysics Data System (ADS)

    Jain Figueroa, A.; McLaughlin, D.

    2016-12-01

    The Grand Ethiopian Renaissance Dam (GERD), on the Blue Nile is an example of water resource management underpinning food, water and energy security. Downstream countries have long expressed concern about water projects in Ethiopia because of possible diversions to agricultural uses that could reduce flow in the Nile. Such diversions are attractive to Ethiopia as a partial solution to its food security problems but they could also conflict with hydropower revenue from GERD. This research estimates an upper bound on diversions above the GERD project by considering the potential for irrigated agriculture expansion and, in particular, the availability of water and land resources for crop production. Although many studies have aimed to simulate downstream flows for various Nile basin management plans, few have taken the perspective of bounding the likely impacts of upstream agricultural development. The approach is to construct an optimization model to establish a bound on Upper Blue Nile (UBN) agricultural development, paying particular attention to soil suitability and seasonal variability in climate. The results show that land and climate constraints impose significant limitations on crop production. Only 25% of the land area is suitable for irrigation due to the soil, slope and temperature constraints. When precipitation is also considered only 11% of current land area could be used in a way that increases water consumption. The results suggest that Ethiopia could consume an additional 3.75 billion cubic meters (bcm) of water per year, through changes in land use and storage capacity. By exploiting this irrigation potential, Ethiopia could potentially decrease the annual flow downstream of the UBN by 8 percent from the current 46 bcm/y to the modeled 42 bcm/y.

  1. Integrated Resources Management Approach to Ensuring Sustainable Food Security in Nigeria-The Nexus of Rice Production in Niger State

    NASA Astrophysics Data System (ADS)

    Omotoso, T.

    2015-12-01

    By 2050, the world will need to feed 9 billion people. This will require a 60% increase in agricultural production and subsequently a 6% increase in water use by the agricultural sector alone. By 2030, global water demand is expected to increase by 40%, mostly in developing countries like Nigeria (Addams, Boccaletti, Kerlin, & Stuchtey, 2009) and global energy demand is expected to increase by 33% in 2035, also, mostly in emerging economies (IEA, 2013). These resources have to be managed efficiently in preparation for these future demands. Population growth leads to increased demand for water, energy and food. More food production will lead to more water-for-food and energy-for-food usage; and more demand for energy will lead to more water-for-energy needs. This nexus between water, energy and food is poorly understood and furthermore, complicated by external drivers such as climate change. Niger State Nigeria, which is blessed with abundant water and arable land resources, houses the three hydropower dams in Nigeria and one of the governments' proposed Staple Crops Processing Zones (SCPZ) for rice production. Both of these capital intensive investments depend heavily on water resources and are all highly vulnerable to changes in climate. Thus, it is essential to know how the local climate in this state will likely change and its impacts on water, energy and food security, so that policy makers can make informed mitigation/adaptation plans; operational and investment decisions. The objective of this project is to provide information, using an integrated resources management approach, on the effects of future climate changes on water, energy (hydropower) and food resources in Niger State, Nigeria and improve knowledge on the interlinkages between water, energy and food at a local scale.

  2. Disentangling the root- and detritus-based food chain in the micro-food web of an arable soil by plant removal

    PubMed Central

    Glavatska, Olena; Müller, Karolin; Butenschoen, Olaf; Schmalwasser, Andreas; Kandeler, Ellen; Scheu, Stefan; Totsche, Kai Uwe

    2017-01-01

    Soil food web structure and function is primarily determined by the major basal resources, which are living plant tissue, root exudates and dead organic matter. A field experiment was performed to disentangle the interlinkage of the root-and detritus-based soil food chains. An arable site was cropped either with maize, amended with maize shoot litter or remained bare soil, representing food webs depending on roots, aboveground litter and soil organic matter as predominant resource, respectively. The soil micro-food web, i.e. microorganisms and nematodes, was investigated in two successive years along a depth transect. The community composition of nematodes was used as model to determine the changes in the rhizosphere, detritusphere and bulk soil food web. In the first growing season the impact of treatments on the soil micro-food web was minor. In the second year plant-feeding nematodes increased under maize, whereas after harvest the Channel Index assigned promotion of the detritivore food chain, reflecting decomposition of root residues. The amendment with litter did not foster microorganisms, instead biomass of Gram-positive and Gram-negative bacteria as well as that of fungi declined in the rooted zone. Likely higher grazing pressure by nematodes reduced microbial standing crop as bacterial and fungal feeders increased. However, populations at higher trophic levels were not promoted, indicating limited flux of litter resources along the food chain. After two years of bare soil microbial biomass and nematode density remained stable, pointing to soil organic matter-based resources that allow bridging periods with deprivation. Nematode communities were dominated by opportunistic taxa that are competitive at moderate resource supply. In sum, removal of plants from the system had less severe effects than expected, suggesting considerable food web resilience to the disruption of both the root and detrital carbon channel, pointing to a legacy of organic matter resources in arable soils. PMID:28704438

  3. Disentangling the root- and detritus-based food chain in the micro-food web of an arable soil by plant removal.

    PubMed

    Glavatska, Olena; Müller, Karolin; Butenschoen, Olaf; Schmalwasser, Andreas; Kandeler, Ellen; Scheu, Stefan; Totsche, Kai Uwe; Ruess, Liliane

    2017-01-01

    Soil food web structure and function is primarily determined by the major basal resources, which are living plant tissue, root exudates and dead organic matter. A field experiment was performed to disentangle the interlinkage of the root-and detritus-based soil food chains. An arable site was cropped either with maize, amended with maize shoot litter or remained bare soil, representing food webs depending on roots, aboveground litter and soil organic matter as predominant resource, respectively. The soil micro-food web, i.e. microorganisms and nematodes, was investigated in two successive years along a depth transect. The community composition of nematodes was used as model to determine the changes in the rhizosphere, detritusphere and bulk soil food web. In the first growing season the impact of treatments on the soil micro-food web was minor. In the second year plant-feeding nematodes increased under maize, whereas after harvest the Channel Index assigned promotion of the detritivore food chain, reflecting decomposition of root residues. The amendment with litter did not foster microorganisms, instead biomass of Gram-positive and Gram-negative bacteria as well as that of fungi declined in the rooted zone. Likely higher grazing pressure by nematodes reduced microbial standing crop as bacterial and fungal feeders increased. However, populations at higher trophic levels were not promoted, indicating limited flux of litter resources along the food chain. After two years of bare soil microbial biomass and nematode density remained stable, pointing to soil organic matter-based resources that allow bridging periods with deprivation. Nematode communities were dominated by opportunistic taxa that are competitive at moderate resource supply. In sum, removal of plants from the system had less severe effects than expected, suggesting considerable food web resilience to the disruption of both the root and detrital carbon channel, pointing to a legacy of organic matter resources in arable soils.

  4. Re-envisioning global agricultural trade: time for a paradigm shift to ensure food security and population health in low-income countries.

    PubMed

    Pirkle, Catherine M; Poliquin, Hélène; Sia, Drissa; Kouakou, Kouassi Joseph; Sagna, Tani

    2015-03-01

    In this commentary, we use examples from West Africa to highlight how the liberalization of global agricultural trade exacerbates population health inequalities by threatening the livelihoods and food security of communities in low-income settings. We highlight the exploitative nature of trade agreements with West African countries demonstrating how these agreements disincentivize local agricultural investment and take jobs away from small-scale farmers. Further, we link agricultural trade liberalization to increased food insecurity, malnutrition, and exposure to environmental contaminants. Finally, we propose a paradigm shift that advocates for food sovereignty and the right to food. © The Author(s) 2014.

  5. Exceptionally high levels of lead pollution in the Balkans from the Early Bronze Age to the Industrial Revolution.

    PubMed

    Longman, Jack; Veres, Daniel; Finsinger, Walter; Ersek, Vasile

    2018-05-29

    The Balkans are considered the birthplace of mineral resource exploitation and metalworking in Europe. However, since knowledge of the timing and extent of metallurgy in southeastern Europe is largely constrained by discontinuous archaeological findings, the long-term environmental impact of past mineral resource exploitation is not fully understood. Here, we present a high-resolution and continuous geochemical record from a peat bog in western Serbia, providing a clear indication of the extent and magnitude of environmental pollution in this region, and a context in which to place archaeological findings. We observe initial evidence of anthropogenic lead (Pb) pollution during the earliest part of the Bronze Age [∼3,600 years before Common Era (BCE)], the earliest such evidence documented in European environmental records. A steady, almost linear increase in Pb concentration after 600 BCE, until ∼1,600 CE is observed, documenting the development in both sophistication and extent of southeastern European metallurgical activity throughout Antiquity and the medieval period. This provides an alternative view on the history of mineral exploitation in Europe, with metal-related pollution not ceasing at the fall of the western Roman Empire, as was the case in western Europe. Further comparison with other Pb pollution records indicates the amount of Pb deposited in the Balkans during the medieval period was, if not greater, at least similar to records located close to western European mining regions, suggestive of the key role the Balkans have played in mineral resource exploitation in Europe over the last 5,600 years. Copyright © 2018 the Author(s). Published by PNAS.

  6. Resource Management in QoS-Aware Wireless Cellular Networks

    ERIC Educational Resources Information Center

    Zhang, Zhi

    2011-01-01

    Emerging broadband wireless networks that support high speed packet data with heterogeneous quality of service (QoS) requirements demand more flexible and efficient use of the scarce spectral resource. Opportunistic scheduling exploits the time-varying, location-dependent channel conditions to achieve multiuser diversity. In this work, we study…

  7. Coordinated Radar Resource Management for Networked Phased Array Radars

    DTIC Science & Technology

    2014-12-01

    Coordinated radar resource management for networked phased array radars Peter W. Moo and Zhen Ding Radar Sensing & Exploitation Section Defence...15] P.W. Moo . Scheduling for multifunction radar via two-slope benefit functions. Radar, Sonar Navigation, IET, 5(8):884 –894, Oct. 2011. [16] M.I

  8. Boldness predicts an individual's position along an exploration-exploitation foraging trade-off.

    PubMed

    Patrick, Samantha C; Pinaud, David; Weimerskirch, Henri

    2017-09-01

    Individuals do not have complete information about the environment and therefore they face a trade-off between gathering information (exploration) and gathering resources (exploitation). Studies have shown individual differences in components of this trade-off but how stable these strategies are in a population and the intrinsic drivers of these differences is not well understood. Top marine predators are expected to experience a particularly strong trade-off as many species have large foraging ranges and their prey often have a patchy distribution. This environment leads these species to exhibit pronounced exploration and exploitation phases but differences between individuals are poorly resolved. Personality differences are known to be important in foraging behaviour but also in the trade-off between exploration and exploitation. Here we test whether personality predicts an individual exploration-exploitation strategy using wide ranging wandering albatrosses (Diomedea exulans) as a model system. Using GPS tracking data from 276 wandering albatrosses, we extract foraging parameters indicative of exploration (searching) and exploitation (foraging) and show that foraging effort, time in patch and size of patch are strongly correlated, demonstrating these are indicative of an exploration-exploitation (EE) strategy. Furthermore, we show these are consistent within individuals and appear stable in the population, with no reproductive advantage. The searching and foraging behaviour of bolder birds placed them towards the exploration end of the trade-off, whereas shy birds showed greater exploitation. This result provides a mechanism through which individual foraging strategies may emerge. Age and sex affected components of the trade-off, but not the trade-off itself, suggesting these factors may drive behavioural compensation to maintain resource acquisition and this was supported by the evidence that there were no fitness consequence of any EE trait nor the trade-off itself. These results demonstrate a clear trade-off between information gathering and exploitation of prey patches, and reveals for the first time that boldness may drive these differences. This provides a mechanism through which widely reported links between personality and foraging may emerge. © 2017 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.

  9. Relating trophic resources to community structure: a predictive index of food availability

    PubMed Central

    Edgar, Graham J.

    2017-01-01

    The abundance and the distribution of trophic resources available for consumers influence the productivity and the diversity of natural communities. Nevertheless, assessment of the actual abundance of food items available for individual trophic groups has been constrained by differences in methods and metrics used by various authors. Here we develop an index of food abundance, the framework of which can be adapted for different ecosystems. The relative available food index (RAFI) is computed by considering standard resource conditions of a habitat and the influence of various generalized anthropogenic and natural factors. RAFI was developed using published literature on food abundance and validated by comparison of predictions versus observed trophic resources across various marine sites. RAFI tables here proposed can be applied to a range of marine ecosystems for predictions of the potential abundance of food available for each trophic group, hence permitting exploration of ecological theories by focusing on the deviation from the observed to the expected. PMID:28386417

  10. Patterns of distribution and abundance of the stalked barnacle (Pollicipes pollicipes) in the central and southwest coast of continental Portugal

    NASA Astrophysics Data System (ADS)

    Sousa, Alina; Jacinto, David; Penteado, Nélia; Martins, Pedro; Fernandes, Joana; Silva, Teresa; Castro, João J.; Cruz, Teresa

    2013-10-01

    The stalked barnacle Pollicipes pollicipes is a cirriped crustacean that lives on very exposed rocky shores. This barnacle is the most important economical resource on intertidal rocky shores of continental Portugal. It is highly prized as food and heavily exploited (professional and recreational fishery), but fishery data are scarce and do not estimate the real pressure upon this resource. Despite its socio-economic interest, specific regulations on this fishery are recent and different along the Portuguese coast. Four regions with different regulation can be identified: the marine reserve “Reserva Natural das Berlengas” (RNB) and the marine park “Parque Marinho Prof. Luiz Saldanha” (PMLS) (both in central Portugal); the natural park located in SW Portugal (“Parque Natural do Sudoeste Alentejano e Costa Vicentina”, PNSACV); and the rest of the coast. The main objective of the present study was to study the spatial patterns of percentage cover, biomass, density and size structure of P. pollicipes in areas with different exploitation regimes, including harvested areas and no-take areas. Additionally, variability between mid shore and low shore barnacles was also analysed. Seven areas were sampled with a variable number of sites (a total of 24) randomly sampled in each area during 2011. Photographs and image analysis (percentage cover) and destructive sampling (density, biomass and size) were used. In general, percentage cover, biomass and density were higher in mid shore when compared to low shore, namely in harvested areas. Low shore barnacles had a higher proportion of adults with moderate and high commercial value, while juveniles were relatively more abundant at mid shore. There were no consistent differences in the patterns of distribution and abundance of P. pollicipes among areas subject to different exploitation regimes. The most different area was the harvested area by professional fishers in RNB, where the highest biomass within the study was registered (mid shore, 7.7 kg·m- 2). Barnacles within this area presented a higher proportion of adults with commercial value, while recruits and juveniles were relatively more abundant in other areas. The hypothesis of a highest percentage cover, density and biomass in the low shore of no-take sites was not supported.

  11. Anthropization of groundwater resources in the Mediterranean region: processes and challenges

    NASA Astrophysics Data System (ADS)

    Leduc, Christian; Pulido-Bosch, Antonio; Remini, Boualem

    2017-09-01

    A comprehensive overview is provided of processes and challenges related to Mediterranean groundwater resources and associated changes in recent decades. While most studies are focused thematically and/or geographically, this paper addresses different stages of groundwater exploitation in the region and their consequences. Examples emphasize the complex interactions between the physical and social dimensions of uses and evolution of groundwater. In natural conditions, Mediterranean groundwater resources represent a wide range of hydrogeological contexts, recharge conditions and rates of exploitation. They have been actively exploited for millennia but their pseudo-natural regimes have been considerably modified in the last 50 years, especially to satisfy agricultural demand (80% of total water consumption in North Africa), as well as for tourism and coastal cities. Climate variability affects groundwater dynamics but the various forms of anthropization are more important drivers of hydrological change, including changes in land use and vegetation, hydraulic works, and intense pumpings. These changes affect both the quantity and quality of groundwater at different scales, and modify the nature of hydrogeological processes, their location, timing, and intensity. The frequent cases of drastic overexploitation illustrate the fragility of Mediterranean groundwater resources and the limits of present forms of management. There is no easy way to maintain or recover sustainability, which is often threatened by short-term interests. To achieve this goal, a significant improvement in hydrogeological knowledge and closer collaboration between the various disciplines of water sciences are indispensable.

  12. Study on the Potential Development of Rainwater Utilization in the Hilly City of Southern China

    NASA Astrophysics Data System (ADS)

    Fu, Xiaoran; Liu, Jiahong; Shao, Weiwei; Zhang, Haixing

    2017-12-01

    Aimed at the current flood problems and the contradiction between supply and demand of water resources in the southern cities of China, the comprehensive utilization of Urban Rainwater Resources (URRs) is a significant solution. At present, the research on the comprehensive utilization system of urban rainwater resources in China is still immature, especially the lack of a comprehensive method for the comprehensive utilization of the rainwater and flood resources in the south. Based on the current mode for utilization of URRs at home and abroad, Fenghuang County in Hunan Province was taken as a case of study, which is a typical mountainous city in the southern China. And the potential development of URRs was simulated and evaluated with a comparison of before and after the exploitation and utilization of URRs in this paper. The reduction effect of flood and waterlogging on the ancient city area is analyzed from SWMM. The simulation results show that the potential of exploitation and utilization of URRs in Fenghuang county is remarkable under the mode of exploitation and utilization which is given priority to flood prevention and control, and the annual development potential is 4.865×105 m3. The rainwater utilization measures of flood control effect is obvious with this mode, and the relevant research results can provide theoretical and technical support for enhancing urban water security capability, water conservation capacity, and disaster mitigation of urban flood.

  13. Identifying potential disaster zones around the Verkhnekamskoye potash deposit (Russia) using advanced information technology (IT)

    NASA Astrophysics Data System (ADS)

    Royer, J. J.; Filippov, L. O.

    2017-07-01

    This work aims at improving the exploitation of the K, Mg, salts ore of the Verkhnekamskoye deposit using advanced information technology (IT) such as 3D geostatistical modeling techniques together with high performance flotation. It is expected to provide a more profitable exploitation of the actual deposit avoiding the formation of dramatic sinkholes by a better knowledge of the deposit. The GeoChron modelling method for sedimentary formations (Mallet, 2014) was used to improve the knowledge of the Verkhnekamskoye potash deposit, Perm region, Russia. After a short introduction on the modern theory of mathematical modelling applied to mineral resources exploitation and geology, new results are presented on the sedimentary architecture of the ore deposit. They enlighten the structural geology and the fault orientations, a key point for avoiding catastrophic water inflows recharging zone during exploitation. These results are important for avoiding catastrophic sinkholes during exploitation.

  14. Competition between a nonallelopathic phytoplankton and an allelopathic phytoplankton species under predation.

    PubMed

    Kengwoung-Keumo, Jean-Jacques

    2016-08-01

    We propose a model of two-species competition in the chemostat for a single growth-limiting, nonreproducing resource that extends that of Roy [38]. The response functions are specified to be Michaelis-Menten, and there is no predation in Roy's work. Our model generalizes Roy's model to general uptake functions. The competition is exploitative so that species compete by decreasing the common pool of resources. The model also allows allelopathic effects of one toxin-producing species, both on itself (autotoxicity) and on its nontoxic competitor (phytotoxicity). We show that a stable coexistence equilibrium exists as long as (a) there are allelopathic effects and (b) the input nutrient concentration is above a critical value. The model is reconsidered under instantaneous nutrient recycling. We further extend this work to include a zooplankton species as a fourth interacting component to study the impact of predation on the ecosystem. The zooplankton species is allowed to feed only on the two phytoplankton species which are its perfectly substitutable resources. Each of the models is analyzed for boundedness, equilibria, stability, and uniform persistence (or permanence). Each model structure fits very well with some harmful algal bloom observations where the phytoplankton assemblage can be envisioned in two compartments, toxin producing and non-toxic. The Prymnesium parvum literature, where the suppressing effects of allelochemicals are quite pronounced, is a classic example. This work advances knowledge in an area of research becoming ever more important, which is understanding the functioning of allelopathy in food webs.

  15. POLITICS OF BIOPIRACY: AN ADVENTURE INTO HOODIA/XHOBA PATENTING IN SOUTHERN AFRICA.

    PubMed

    Amusan, Lere

    2017-01-01

    Africa is being described as the wretched of the earth, despite this, the continent is endowed with natural resources, dynamic ecosystem, and different species of plants and animals, and species derivatives. This paper area of departure is to focus on Hoodia, a plant that is being a source of food, medicine and water for the San and Khoe indigenous peoples before the advent of Europeans into southern Africa. South African Council for Scientific and Industrial Research (CSIR) dubiously patented Hoodia without observing the basic indices of geographical indications (GIs), indigenous knowledge (IK), novelty, access sharing benefit (ASB), prior informed consent (PIC) and sustainability of ecosystem before the rights was sold to Phytopharm pharmaceutical company. This article adopts neoliberal thesis with emphasis on complex interdependence theory of organic linkages between developing and developed countries. Secondary sources of information taken into account of qualitative and critical discuss content analyses dominate this paper. The paper recommends a linkage between developed and developing states based on endowment theory and comparative advantage with the notion of adhering to the Convention on Biological Diversity (CBD) which has three objectives: the conservation of biodiversity; the sustainable utilisation of indigenous biological resources (IBR); and fair and equitable benefit sharing. The paper recommends that there is a need to follow CBD and other relevant international regimes that promote equal exchange in exploitation of Africa resources as against the present skewed arrangement that is in favour of multinational corporations (MNCs).

  16. Genetic Transformation and Genomic Resources for Next-Generation Precise Genome Engineering in Vegetable Crops

    PubMed Central

    Cardi, Teodoro; D’Agostino, Nunzio; Tripodi, Pasquale

    2017-01-01

    In the frame of modern agriculture facing the predicted increase of population and general environmental changes, the securement of high quality food remains a major challenge to deal with. Vegetable crops include a large number of species, characterized by multiple geographical origins, large genetic variability and diverse reproductive features. Due to their nutritional value, they have an important place in human diet. In recent years, many crop genomes have been sequenced permitting the identification of genes and superior alleles associated with desirable traits. Furthermore, innovative biotechnological approaches allow to take a step forward towards the development of new improved cultivars harboring precise genome modifications. Sequence-based knowledge coupled with advanced biotechnologies is supporting the widespread application of new plant breeding techniques to enhance the success in modification and transfer of useful alleles into target varieties. Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 system, zinc-finger nucleases, and transcription activator-like effector nucleases represent the main methods available for plant genome engineering through targeted modifications. Such technologies, however, require efficient transformation protocols as well as extensive genomic resources and accurate knowledge before they can be efficiently exploited in practical breeding programs. In this review, we revise the state of the art in relation to availability of such scientific and technological resources in various groups of vegetables, describe genome editing results obtained so far and discuss the implications for future applications. PMID:28275380

  17. Genetic diversity and genomic resources available for the small millet crops to accelerate a New Green Revolution

    PubMed Central

    Goron, Travis L.; Raizada, Manish N.

    2015-01-01

    Small millets are nutrient-rich food sources traditionally grown and consumed by subsistence farmers in Asia and Africa. They include finger millet (Eleusine coracana), foxtail millet (Setaria italica), kodo millet (Paspalum scrobiculatum), proso millet (Panicum miliaceum), barnyard millet (Echinochloa spp.), and little millet (Panicum sumatrense). Local farmers value the small millets for their nutritional and health benefits, tolerance to extreme stress including drought, and ability to grow under low nutrient input conditions, ideal in an era of climate change and steadily depleting natural resources. Little scientific attention has been paid to these crops, hence they have been termed “orphan cereals.” Despite this challenge, an advantageous quality of the small millets is that they continue to be grown in remote regions of the world which has preserved their biodiversity, providing breeders with unique alleles for crop improvement. The purpose of this review, first, is to highlight the diverse traits of each small millet species that are valued by farmers and consumers which hold potential for selection, improvement or mechanistic study. For each species, the germplasm, genetic and genomic resources available will then be described as potential tools to exploit this biodiversity. The review will conclude with noting current trends and gaps in the literature and make recommendations on how to better preserve and utilize diversity within these species to accelerate a New Green Revolution for subsistence farmers in Asia and Africa. PMID:25852710

  18. POLITICS OF BIOPIRACY: AN ADVENTURE INTO HOODIA/XHOBA PATENTING IN SOUTHERN AFRICA

    PubMed Central

    Amusan, Lere

    2017-01-01

    Background: Africa is being described as the wretched of the earth, despite this, the continent is endowed with natural resources, dynamic ecosystem, and different species of plants and animals, and species derivatives. This paper area of departure is to focus on Hoodia, a plant that is being a source of food, medicine and water for the San and Khoe indigenous peoples before the advent of Europeans into southern Africa. South African Council for Scientific and Industrial Research (CSIR) dubiously patented Hoodia without observing the basic indices of geographical indications (GIs), indigenous knowledge (IK), novelty, access sharing benefit (ASB), prior informed consent (PIC) and sustainability of ecosystem before the rights was sold to Phytopharm pharmaceutical company. Materials and methods: This article adopts neoliberal thesis with emphasis on complex interdependence theory of organic linkages between developing and developed countries. Secondary sources of information taken into account of qualitative and critical discuss content analyses dominate this paper. Result: The paper recommends a linkage between developed and developing states based on endowment theory and comparative advantage with the notion of adhering to the Convention on Biological Diversity (CBD) which has three objectives: the conservation of biodiversity; the sustainable utilisation of indigenous biological resources (IBR); and fair and equitable benefit sharing. Conclusion: The paper recommends that there is a need to follow CBD and other relevant international regimes that promote equal exchange in exploitation of Africa resources as against the present skewed arrangement that is in favour of multinational corporations (MNCs). PMID:28480387

  19. Winter active bumblebees (Bombus terrestris) achieve high foraging rates in urban Britain.

    PubMed

    Stelzer, Ralph J; Chittka, Lars; Carlton, Marc; Ings, Thomas C

    2010-03-05

    Foraging bumblebees are normally associated with spring and summer in northern Europe. However, there have been sightings of the bumblebee Bombus terrestris during the warmer winters in recent years in southern England. But what floral resources are they relying upon during winter and how much winter forage can they collect? To test if urban areas in the UK provide a rich foraging niche for bees we set up colonies of B. terrestris in the field during two late winter periods (2005/6 & 2006/7) in London, UK, and measured their foraging performance. Fully automatic radio-frequency identification (RFID) technology was used in 2006/7 to enable us to record the complete foraging activity of individually tagged bees. The number of bumblebees present during winter (October 2007 to March 2008) and the main plants they visited were also recorded during transect walks. Queens and workers were observed throughout the winter, suggesting a second generation of bee colonies active during the winter months. Mass flowering shrubs such as Mahonia spp. were identified as important food resources. The foraging experiments showed that bees active during the winter can attain nectar and pollen foraging rates that match, and even surpass, those recorded during summer. B. terrestris in the UK are now able to utilise a rich winter foraging resource in urban parks and gardens that might at present still be under-exploited, opening up the possibility of further changes in pollinator phenology.

  20. What to eat now? Shifts in polar bear diet during the ice-free season in western Hudson Bay.

    PubMed

    Gormezano, Linda J; Rockwell, Robert F

    2013-09-01

    Under current climate trends, spring ice breakup in Hudson Bay is advancing rapidly, leaving polar bears (Ursus maritimus) less time to hunt seals during the spring when they accumulate the majority of their annual fat reserves. For this reason, foods that polar bears consume during the ice-free season may become increasingly important in alleviating nutritional stress from lost seal hunting opportunities. Defining how the terrestrial diet might have changed since the onset of rapid climate change is an important step in understanding how polar bears may be reacting to climate change. We characterized the current terrestrial diet of polar bears in western Hudson Bay by evaluating the contents of passively sampled scat and comparing it to a similar study conducted 40 years ago. While the two terrestrial diets broadly overlap, polar bears currently appear to be exploiting increasingly abundant resources such as caribou (Rangifer tarandus) and snow geese (Chen caerulescens caerulescens) and newly available resources such as eggs. This opportunistic shift is similar to the diet mixing strategy common among other Arctic predators and bear species. We discuss whether the observed diet shift is solely a response to a nutritional stress or is an expression of plastic foraging behavior.

  1. What to eat now? Shifts in polar bear diet during the ice-free season in western Hudson Bay

    PubMed Central

    Gormezano, Linda J; Rockwell, Robert F

    2013-01-01

    Under current climate trends, spring ice breakup in Hudson Bay is advancing rapidly, leaving polar bears (Ursus maritimus) less time to hunt seals during the spring when they accumulate the majority of their annual fat reserves. For this reason, foods that polar bears consume during the ice-free season may become increasingly important in alleviating nutritional stress from lost seal hunting opportunities. Defining how the terrestrial diet might have changed since the onset of rapid climate change is an important step in understanding how polar bears may be reacting to climate change. We characterized the current terrestrial diet of polar bears in western Hudson Bay by evaluating the contents of passively sampled scat and comparing it to a similar study conducted 40 years ago. While the two terrestrial diets broadly overlap, polar bears currently appear to be exploiting increasingly abundant resources such as caribou (Rangifer tarandus) and snow geese (Chen caerulescens caerulescens) and newly available resources such as eggs. This opportunistic shift is similar to the diet mixing strategy common among other Arctic predators and bear species. We discuss whether the observed diet shift is solely a response to a nutritional stress or is an expression of plastic foraging behavior. PMID:24223286

  2. Foraging movements of Audouin’s gull (Larus audouinii) in the Ebro Delta, NW Mediterranean: A preliminary satellite-tracking study

    NASA Astrophysics Data System (ADS)

    Christel, Isadora; Navarro, Joan; del Castillo, Marcos; Cama, Albert; Ferrer, Xavier

    2012-01-01

    A knowledge of the foraging strategies of marine predators is essential to understand the intrinsic factors controlling their distribution, abundance and their ecological function within the marine ecosystem. Here, we investigated for the first time the foraging movements and activity patterns of Audouin's gull Larus audouinii by using satellite-tracking data from eight breeding adults in the main colony of the species worldwide (Ebro Delta, NW Mediterranean). Tagged gulls foraged in the marine area close to the breeding colony (62% of foraging locations) and in the terrestrial area of the Ebro Delta (mainly rice fields; 38% of foraging locations). The foraging activity patterns changed significantly throughout the day; lower from dusk through the first half of the night (19-1 h; 32% of active locations) and higher during the rest of the day (1-19 h; 75.5 ± 4.3% of active locations). These results confirm the foraging plasticity of this seabird and, based on previous information about the dietary habits of this species, we hypothesize how its time-dependent activity patterns and habitat use could be associated with variations in the availability of marine food resources (e.g. diel vertical migrations of pelagic fish) and the exploitation of terrestrial resources (e.g. American crayfish Procambarus clarkii).

  3. Human response to Holocene warming on the Cantabrian Coast (northern Spain): an unexpected outcome

    NASA Astrophysics Data System (ADS)

    Marín-Arroyo, Ana B.

    2013-12-01

    Subsistence was characterized during the Pleistocene to Holocene transition on the Cantabrian Coast (northern Spain) by a progressive diet widening, with a greater exploitation of marine environments and a more intense consumption of low-ranked species. This trend was also accompanied by a general and noticeable decrease in the amount of ungulates that were recovered from a set of archaeological sites clearly dominated by shells. The causes behind this change in the economic practice of the last hunter-gatherer groups are still being debated. There are currently two opposing views on the matter, with some scholars defending the role of demographic pressure as the main driving force, while other researchers invoke the importance of the environment in the food procurement preferences that were adopted. Due to their overwhelming abundance, the debate has been mainly focused on marine resources, whereas the comparatively less-represented macromammal assemblages have been poorly interpreted. However, it is precisely this scarcity that makes them so remarkable. Here, a new interpretation of the available data is presented, with a special focus on the identification of overhunting evidence and on the comparative productivity of each type of resource. Altogether, the demographic hypothesis seems to be more coherent with the existing facts.

  4. Removal of clay by stingless bees: load size and moisture selection.

    PubMed

    Costa-Pereira, Raul

    2014-09-01

    Some organisms disperse energy, associated with the transportation of resource, which is not necessarily food. Stingless bees of Central Amazonia (Melipona flavolineata and M. lateralis) collect clay in banks along streams for nest building. The moisture of the clay varies along the bank, and bees collect clay from specific location, indicating that there is some sort of preference regarding their selection. This study aims at identifying: if larger bees carry more clay; if there is a preference for moisture of substrates; and if bees are less efficient accumulating and transporting clay when it is wet. In order to do so, I measured the size of the bees and of the pellets of clay found in the corbicula. I set up a field experiment to test substrate preferences. The amount of clay transported, increased exponentially in accordance to the size of the bee, and the preferred substrate was the driest clay. The amount and the efficiency of removal of clay were not affected by the moisture of the substrate. Despite the wet clay being denser, it does not reduce the efficiency of exploitation of the resource, but suggests that bees spend more energy to carry the same quantity of wet clay, which may be the underlying mechanism explaining their preference for removing drier clay.

  5. The microeconomics of sexual exploitation of girls and young women in the Peruvian Amazon.

    PubMed

    Mujica, Jaris

    2013-01-01

    This paper examines the sexual exploitation of girls and young women as an increasing phenomenon within the extractive industries of wood, oil, minerals and gas in Peruvian Amazonia. The analysis focuses on the city of Pucallpa and the northern part of the Ucayali River and aims to identify the social and economic dynamics underpinning the commercial sexual exploitation of female children and teenagers around the main river port. The study describes the local operating mechanisms of bars and restaurants in the port, the demand for and perceptions of the sexual exploitation of children and teenagers, and the economic logic that it entails. Using a discourse analytic approach, it is argued that this is a business whose profitability is tied to the trade in alcoholic beverages and foods and which responds to a set of family connections and networks.

  6. Space and Planetary Resources

    NASA Astrophysics Data System (ADS)

    Abbud-Madrid, Angel

    2018-02-01

    The space and multitude of celestial bodies surrounding Earth hold a vast wealth of resources for a variety of space and terrestrial applications. The unlimited solar energy, vacuum, and low gravity in space, as well as the minerals, metals, water, atmospheric gases, and volatile elements on the Moon, asteroids, comets, and the inner and outer planets of the Solar System and their moons, constitute potential valuable resources for robotic and human space missions and for future use in our own planet. In the short term, these resources could be transformed into useful materials at the site where they are found to extend mission duration and to reduce the costly dependence from materials sent from Earth. Making propellants and human consumables from local resources can significantly reduce mission mass and cost, enabling longer stays and fueling transportation systems for use within and beyond the planetary surface. Use of finely grained soils and rocks can serve for habitat construction, radiation protection, solar cell fabrication, and food growth. The same material could also be used to develop repair and replacement capabilities using advanced manufacturing technologies. Following similar mining practices utilized for centuries on Earth, identifying, extracting, and utilizing extraterrestrial resources will enable further space exploration, while increasing commercial activities beyond our planet. In the long term, planetary resources and solar energy could also be brought to Earth if obtaining these resources locally prove to be no longer economically or environmentally acceptable. Throughout human history, resources have been the driving force for the exploration and settling of our planet. Similarly, extraterrestrial resources will make space the next destination in the quest for further exploration and expansion of our species. However, just like on Earth, not all challenges are scientific and technological. As private companies start working toward exploiting the resources from asteroids, the Moon, and Mars, an international legal framework is also needed to regulate commercial exploration and the use of space and planetary resources for the benefit of all humanity. These resources hold the secret to unleash an unprecedented wave of exploration and of economic prosperity by utilizing the full potential and value of space. It is up to us humans here on planet Earth to find the best way to use these extraterrestrial resources effectively and responsibly to make this promise a reality.

  7. Influence of harvesting pressure on demographic tactics: Implications for wildlife management

    USGS Publications Warehouse

    Servanty, S.; Gaillard, J.-M.; Ronchi, F.; Focardi, S.; Baubet, E.; Gimenez, O.

    2011-01-01

    Demographic tactics within animal populations are shaped by selective pressures. Exploitation exerts additional pressures so that differing demographic tactics might be expected among populations with differences in levels of exploitation. Yet little has been done so far to assess the possible consequences of exploitation on the demographic tactics of mammals, even though such information could influence the choice of effective management strategies. Compared with similar-sized ungulate species, wild boar Sus scrofa has high reproductive capabilities, which complicates population management. Using a perturbation analysis, we investigated how population growth rates (??) and critical life-history stages differed between two wild boar populations monitored for several years, one of which was heavily harvested and the other lightly harvested. Asymptotic ?? was 1??242 in the lightly hunted population and 1??115 in the heavily hunted population, while the ratio between the elasticity of adult survival and juvenile survival was 2??63 and 1??27, respectively. A comparative analysis including 21 other ungulate species showed that the elasticity ratio in the heavily hunted population was the lowest ever observed. Compared with expected generation times of similar-sized ungulates (more than 6years), wild boar has a fast life-history speed, especially when facing high hunting pressure. This is well illustrated by our results, where generation times were 3??6years in the lightly hunted population and only 2??3years in the heavily hunted population. High human-induced mortality combined with non-limiting food resources accounted for the accelerated life history of the hunted population because of earlier reproduction. Synthesis and applications. For wild boar, we show that when a population is facing a high hunting pressure, increasing the mortality in only one age-class (e.g. adults or juveniles) may not allow managers to limit population growth. We suggest that simulations of management strategies based on context-specific demographic models are useful for selecting interventions for population control. This type of approach allows the assessment of population response to exploitation by considering a range of plausible scenarios, improving the chance of selecting appropriate management actions. ?? 2011 The Authors. Journal of Applied Ecology ?? 2011 British Ecological Society.

  8. Pyrrolizidine Alkaloids: Chemistry, Pharmacology, Toxicology and Food Safety.

    PubMed

    Moreira, Rute; Pereira, David M; Valentão, Patrícia; Andrade, Paula B

    2018-06-05

    Pyrrolizidine alkaloids (PA) are widely distributed in plants throughout the world, frequently in species relevant for human consumption. Apart from the toxicity that these molecules can cause in humans and livestock, PA are also known for their wide range of pharmacological properties, which can be exploited in drug discovery programs. In this work we review the current body of knowledge regarding the chemistry, toxicology, pharmacology and food safety of PA.

  9. Blue Mountain Lake; An Archeological Survey and an Experimental Study of Inundation Impacts.

    DTIC Science & Technology

    1978-02-01

    Seasonal exploitation of available plant and animal foods , with scheduled occupation of sites reflecting an annual cycle, is often detectable in the...Archeological Significance: Shell is found in many archeological sites, both as artifacts (culturally modified) and as food residue. Quantification of...samples. The vessels (one simal bottle of Tiboriginal manufact ire with the neck broken off and one large jar manufactured in 1973 using aboriginal

  10. Assessing Student Attitudes toward Animal Welfare, Resource Use, and Food Safety.

    ERIC Educational Resources Information Center

    Nordstrom, Patricia A.; Richards, Martha J.; Wilson, Lowell L.; Coe, Brenda L.; Fivek, Marianne L.; Brown, Michele B.

    2000-01-01

    Students participating in the Pennsylvania Governor's School for Agricultural Sciences (n=192) studied animal welfare, resource use, and food safety. They ranked food safety as a primary concern. Students with and without agricultural backgrounds showed positive changes in knowledge and perception of issues after the course. (SK)

  11. Demographic and phenotypic responses of juvenile steelhead trout to spatial predictability of food resources

    Treesearch

    Matthew R. Sloat; Gordon H. Reeves

    2014-01-01

    We manipulated food inputs among patches within experimental streams to determine how variation in foraging behavior influenced demographic and phenotypic responses of juvenile steelhead trout (Oncorhynchus mykiss) to the spatial predictability of food resources. Demographic responses included compensatory adjustments in fish abundance, mean fish...

  12. Life-Long Radar Tracking of Bumblebees

    PubMed Central

    Lim, Ka S.; Reynolds, Andrew M.; Chittka, Lars

    2016-01-01

    Insect pollinators such as bumblebees play a vital role in many ecosystems, so it is important to understand their foraging movements on a landscape scale. We used harmonic radar to record the natural foraging behaviour of Bombus terrestris audax workers over their entire foraging career. Every flight ever made outside the nest by four foragers was recorded. Our data reveal where the bees flew and how their behaviour changed with experience, at an unprecedented level of detail. We identified how each bee’s flights fit into two categories—which we named exploration and exploitation flights—examining the differences between the two types of flight and how their occurrence changed over the course of the bees’ foraging careers. Exploitation of learned resources takes place during efficient, straight trips, usually to a single foraging location, and is seldom combined with exploration of other areas. Exploration of the landscape typically occurs in the first few flights made by each bee, but our data show that further exploration flights can be made throughout the bee’s foraging career. Bees showed striking levels of variation in how they explored their environment, their fidelity to particular patches, ratio of exploration to exploitation, duration and frequency of their foraging bouts. One bee developed a straight route to a forage patch within four flights and followed this route exclusively for six days before abandoning it entirely for a closer location; this second location had not been visited since her first exploratory flight nine days prior. Another bee made only rare exploitation flights and continued to explore widely throughout its life; two other bees showed more frequent switches between exploration and exploitation. Our data shed light on the way bumblebees balance exploration of the environment with exploitation of resources and reveal extreme levels of variation between individuals. PMID:27490662

  13. Life-Long Radar Tracking of Bumblebees.

    PubMed

    Woodgate, Joseph L; Makinson, James C; Lim, Ka S; Reynolds, Andrew M; Chittka, Lars

    2016-01-01

    Insect pollinators such as bumblebees play a vital role in many ecosystems, so it is important to understand their foraging movements on a landscape scale. We used harmonic radar to record the natural foraging behaviour of Bombus terrestris audax workers over their entire foraging career. Every flight ever made outside the nest by four foragers was recorded. Our data reveal where the bees flew and how their behaviour changed with experience, at an unprecedented level of detail. We identified how each bee's flights fit into two categories-which we named exploration and exploitation flights-examining the differences between the two types of flight and how their occurrence changed over the course of the bees' foraging careers. Exploitation of learned resources takes place during efficient, straight trips, usually to a single foraging location, and is seldom combined with exploration of other areas. Exploration of the landscape typically occurs in the first few flights made by each bee, but our data show that further exploration flights can be made throughout the bee's foraging career. Bees showed striking levels of variation in how they explored their environment, their fidelity to particular patches, ratio of exploration to exploitation, duration and frequency of their foraging bouts. One bee developed a straight route to a forage patch within four flights and followed this route exclusively for six days before abandoning it entirely for a closer location; this second location had not been visited since her first exploratory flight nine days prior. Another bee made only rare exploitation flights and continued to explore widely throughout its life; two other bees showed more frequent switches between exploration and exploitation. Our data shed light on the way bumblebees balance exploration of the environment with exploitation of resources and reveal extreme levels of variation between individuals.

  14. Lineage-Specific Responses of Tooth Shape in Murine Rodents (Murinae, Rodentia) to Late Miocene Dietary Change in the Siwaliks of Pakistan

    PubMed Central

    Kimura, Yuri; Jacobs, Louis L.; Flynn, Lawrence J.

    2013-01-01

    Past ecological responses of mammals to climate change are recognized in the fossil record by adaptive significance of morphological variations. To understand the role of dietary behavior on functional adaptations of dental morphology in rodent evolution, we examine evolutionary change of tooth shape in late Miocene Siwalik murine rodents, which experienced a dietary shift toward C4 diets during late Miocene ecological change indicated by carbon isotopic evidence. Geometric morphometric analysis in the outline of upper first molars captures dichotomous lineages of Siwalik murines, in agreement with phylogenetic hypotheses of previous studies (two distinct clades: the Karnimata and Progonomys clades), and indicates lineage-specific functional responses to mechanical properties of their diets. Tooth shapes of the two clades are similar at their sympatric origin but deviate from each other with decreasing overlap through time. Shape change in the Karnimata clade is associated with greater efficiency of propalinal chewing for tough diets than in the Progonomys clade. Larger body mass in Karnimata may be related to exploitation of lower-quality food items, such as grasses, than in smaller-bodied Progonomys. The functional and ecophysiological aspects of Karnimata exploiting C4 grasses are concordant with their isotopic dietary preference relative to Progonomys. Lineage-specific selection was differentially greater in Karnimata, and a faster rate of shape change toward derived Karnimata facilitated inclusion of C4 grasses in the diet. Sympatric speciation in these clades is most plausibly explained by interspecific competition on resource utilization between the two, based on comparisons of our results with the carbon isotope data. Interspecific competition with Karnimata may have suppressed morphological innovation of the Progonomys clade. Pairwise analyses of morphological and carbon isotope data can uncover ecological causes of sympatric speciation and define functional adaptations of teeth to resources. PMID:24155885

  15. Lineage-specific responses of tooth shape in murine rodents (murinae, rodentia) to late Miocene dietary change in the Siwaliks of Pakistan.

    PubMed

    Kimura, Yuri; Jacobs, Louis L; Flynn, Lawrence J

    2013-01-01

    Past ecological responses of mammals to climate change are recognized in the fossil record by adaptive significance of morphological variations. To understand the role of dietary behavior on functional adaptations of dental morphology in rodent evolution, we examine evolutionary change of tooth shape in late Miocene Siwalik murine rodents, which experienced a dietary shift toward C4 diets during late Miocene ecological change indicated by carbon isotopic evidence. Geometric morphometric analysis in the outline of upper first molars captures dichotomous lineages of Siwalik murines, in agreement with phylogenetic hypotheses of previous studies (two distinct clades: the Karnimata and Progonomys clades), and indicates lineage-specific functional responses to mechanical properties of their diets. Tooth shapes of the two clades are similar at their sympatric origin but deviate from each other with decreasing overlap through time. Shape change in the Karnimata clade is associated with greater efficiency of propalinal chewing for tough diets than in the Progonomys clade. Larger body mass in Karnimata may be related to exploitation of lower-quality food items, such as grasses, than in smaller-bodied Progonomys. The functional and ecophysiological aspects of Karnimata exploiting C4 grasses are concordant with their isotopic dietary preference relative to Progonomys. Lineage-specific selection was differentially greater in Karnimata, and a faster rate of shape change toward derived Karnimata facilitated inclusion of C4 grasses in the diet. Sympatric speciation in these clades is most plausibly explained by interspecific competition on resource utilization between the two, based on comparisons of our results with the carbon isotope data. Interspecific competition with Karnimata may have suppressed morphological innovation of the Progonomys clade. Pairwise analyses of morphological and carbon isotope data can uncover ecological causes of sympatric speciation and define functional adaptations of teeth to resources.

  16. An ethnobotanical study of the less known wild edible figs (genus Ficus) native to Xishuangbanna, Southwest China.

    PubMed

    Shi, Yinxian; Hu, Huabin; Xu, Youkai; Liu, Aizhong

    2014-09-24

    The genus Ficus, collectively known as figs, is a key component of tropical forests and is well known for its ethnobotanical importance. In recent decades an increasing number of studies have shown the indigenous knowledge about wild edible Ficus species and their culinary or medicinal value. However, rather little is known about the role of these species in rural livelihoods, because of both species and cultural diversity. In this study we 1) collected the species and ethnic names of wild edible Ficus exploited by four cultural groups in Xishuangbanna, Southwest China, and 2) recorded the collection activities and modes of consumption through semi-structured interviews, 3) investigated the resource management by a statistical survey of their field distribution and cultivation, and 4) compared and estimated the usage intensities by the grading method. The young leaves, leaf buds and young or ripe syconia of 13 Ficus species or varieties are traditionally consumed. All the species had fixed and usually food-related ethnic names. All four cultural groups are experienced in the collection and use of edible Ficus species as vegetables, fruits or beverages, with the surplus sold for cash income. Different cultural groups use the Ficus species at different intensities because of differences in availability, forest dependency and cultural factors. Both the mountain and basin villagers make an effort to realize sustainable collection and meet their own and market needs by resource management in situ or cultivation. In comparison with reports from other parts of the world, ethnic groups in Xishuangbanna exploited more edible Ficus species for young leaves or leaf buds. Most of the edible species undergo a gradient of management intensities following a gradient of manipulation from simple field gathering to ex situ cultivation. This study contributes to our understanding of the origins and diffusion of the knowledge of perception, application and managing a group of particular plant species, and how the local culture, economic and geographical factors influence the process.

  17. Breeding short-tailed shearwaters buffer local environmental variability in south-eastern Australia by foraging in Antarctic waters.

    PubMed

    Berlincourt, Maud; Arnould, John P Y

    2015-01-01

    Establishing patterns of movements of free-ranging animals in marine ecosystems is crucial for a better understanding of their feeding ecology, life history traits and conservation. As central place foragers, the habitat use of nesting seabirds is heavily influenced by the resources available within their foraging range. We tested the prediction that during years with lower resource availability, short-tailed shearwaters (Puffinus tenuirostris) provisioning chicks should increase their foraging effort, by extending their foraging range and/or duration, both when foraging in neritic (short trips) and distant oceanic waters (long trips). Using both GPS and geolocation data-loggers, at-sea movements and habitat use were investigated over three breeding seasons (2012-14) at two colonies in southeastern Australia. Most individuals performed daily short foraging trips over the study period and inter-annual variations observed in foraging parameters where mainly due to few individuals from Griffith Island, performing 2-day trips in 2014. When performing long foraging trips, this study showed that individuals from both colonies exploited similar zones in the Southern Ocean. The results of this study suggest that individuals could increase their foraging range while exploiting distant feeding zones, which could indicate that short-tailed shearwaters forage in Antarctic waters not only to maintain their body condition but may also do so to buffer against local environmental stochasticity. Lower breeding performances were associated with longer foraging trips to distant oceanic waters in 2013 and 2014 indicating they could mediate reductions in food availability around the breeding colonies by extending their foraging range in the Southern Ocean. This study highlights the importance of foraging flexibility as a fundamental aspect of life history in coastal/pelagic marine central place foragers living in highly variable environments and how these foraging strategies are use to buffer this variability.

  18. Food preparation by young adults is associated with better diet quality.

    PubMed

    Larson, Nicole I; Perry, Cheryl L; Story, Mary; Neumark-Sztainer, Dianne

    2006-12-01

    To describe food-preparation behaviors, cooking skills, resources for preparing food, and associations with diet quality among young adults. Cross-sectional analyses were performed in a sample of young adults who responded to the second wave of a population-based longitudinal study. Measures pertaining to food preparation were self-reported and dietary intake was assessed by a food frequency questionnaire, both by a mailed survey. Males (n = 764) and females (n = 946) ages 18 to 23 years. Cross-tabulations and chi2 tests were used to examine associations between food preparation, skills/resources for preparing foods, and characteristics of young adults. Mixed regression models were used to generate expected probabilities of meeting the Healthy People 2010 dietary objectives according to reported behaviors and skills/resources. Food-preparation behaviors were not performed by the majority of young adults even weekly. Sex (male), race (African American), and living situation (campus housing) were significantly related to less frequent food preparation. Lower perceived adequacy of skills and resources for food preparation was related to reported race (African American or Hispanic) and student status (part-time or not in school). The most common barrier to food preparation was lack of time, reported by 36% of young adults. Young adults who reported frequent food preparation reported less frequent fast-food use and were more likely to meet dietary objectives for fat (P < 0.001), calcium (P < 0.001), fruit (P < 0.001), vegetable (P < 0.001), and whole-grain (P = 0.003) consumption. To improve dietary intake, interventions among young adults should teach skills for preparing quick and healthful meals.

  19. Influence of juice processing factors on quality of black chokeberry pomace as a future resource for colour extraction.

    PubMed

    Vagiri, Michael; Jensen, Martin

    2017-02-15

    Aronia melanocarpa berries are a rich source of anthocyanins and its pomace, a by-product of juice processing, could be efficiently used for extraction of natural colours for the food industry. This study evaluated the influence blanching, freezing, maceration temperatures (2°C, 50°C) and enzyme treatments before juice pressing on the yield and anthocyanin composition of both juice and pomace. Total anthocyanin levels in pomace were affected mostly by enzyme treatment followed by maceration temperature. The pre-heating of the mash prior to processing increased juice yield and retention of anthocyanins in the pomace. Cold maceration of frozen berries without enzyme addition gave the highest concentrations of anthocyanins in the pomace, and both cold and hot maceration of fresh unblanched berries with enzyme the lowest. The results support future exploitation of natural colours from pomace side streams of Aronia, thus increasing competitiveness of Aronia berry production. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. The International Oryza Map Alignment Project: development of a genus-wide comparative genomics platform to help solve the 9 billion-people question.

    PubMed

    Jacquemin, Julie; Bhatia, Dharminder; Singh, Kuldeep; Wing, Rod A

    2013-05-01

    The wild relatives of rice contain a virtually untapped reservoir of traits that can be used help drive the 21st century green revolution aimed at solving world food security issues by 2050. To better understand and exploit the 23 species of the Oryza genus the rice research community is developing foundational resources composed of: 1) reference genomes and transcriptomes for all 23 species; 2) advanced mapping populations for functional and breeding studies; and 3) in situ conservation sites for ecological, evolutionary and population genomics. To this end, 16 genome sequencing projects are currently underway, and all completed assemblies have been annotated; and several advanced mapping populations have been developed, and more will be generated, mapped, and phenotyped, to uncover useful alleles. As wild Oryza populations are threatened by human activity and climate change, we also discuss the urgent need for sustainable in situ conservation of the genus. Copyright © 2013 Elsevier Ltd. All rights reserved.

  1. Aggression in Tephritidae Flies: Where, When, Why? Future Directions for Research in Integrated Pest Management.

    PubMed

    Benelli, Giovanni

    2014-12-30

    True fruit flies (Diptera: Tephritidae) include over 4000 species, many of which constitute enormous threats to fruit and vegetable production worldwide. A number of Tephritidae are lekking species, forming aggregations in which males fight to defend a small territory where they court females and mate. Male-male contests also occur in non-lekking species, characterized by resource defense polygyny. Tephritidae females display agonistic behavior to maintain single oviposition sites and reduce larval competition for food. Here, how, where, when and why aggressive interactions occur in Tephritidae flies is reviewed. A number of neglected issues deserving further research are highlighted, with a special focus on diel periodicity of aggression, cues evoking aggressive behavior, the role of previous experience on fighting success and the evolution of behavioral lateralization of aggressive displays. In the final section, future directions to exploit this knowledge in Integrated Pest Management, with particular emphasis on enhancement of Sterile Insect Technique and interspecific competitive displacement in the field are suggested.

  2. Aggression in Tephritidae Flies: Where, When, Why? Future Directions for Research in Integrated Pest Management

    PubMed Central

    Benelli, Giovanni

    2014-01-01

    True fruit flies (Diptera: Tephritidae) include over 4000 species, many of which constitute enormous threats to fruit and vegetable production worldwide. A number of Tephritidae are lekking species, forming aggregations in which males fight to defend a small territory where they court females and mate. Male-male contests also occur in non-lekking species, characterized by resource defense polygyny. Tephritidae females display agonistic behavior to maintain single oviposition sites and reduce larval competition for food. Here, how, where, when and why aggressive interactions occur in Tephritidae flies is reviewed. A number of neglected issues deserving further research are highlighted, with a special focus on diel periodicity of aggression, cues evoking aggressive behavior, the role of previous experience on fighting success and the evolution of behavioral lateralization of aggressive displays. In the final section, future directions to exploit this knowledge in Integrated Pest Management, with particular emphasis on enhancement of Sterile Insect Technique and interspecific competitive displacement in the field are suggested. PMID:26463064

  3. Climate change impact modelling needs to include cross-sectoral interactions

    NASA Astrophysics Data System (ADS)

    Harrison, Paula A.; Dunford, Robert W.; Holman, Ian P.; Rounsevell, Mark D. A.

    2016-09-01

    Climate change impact assessments often apply models of individual sectors such as agriculture, forestry and water use without considering interactions between these sectors. This is likely to lead to misrepresentation of impacts, and consequently to poor decisions about climate adaptation. However, no published research assesses the differences between impacts simulated by single-sector and integrated models. Here we compare 14 indicators derived from a set of impact models run within single-sector and integrated frameworks across a range of climate and socio-economic scenarios in Europe. We show that single-sector studies misrepresent the spatial pattern, direction and magnitude of most impacts because they omit the complex interdependencies within human and environmental systems. The discrepancies are particularly pronounced for indicators such as food production and water exploitation, which are highly influenced by other sectors through changes in demand, land suitability and resource competition. Furthermore, the discrepancies are greater under different socio-economic scenarios than different climate scenarios, and at the sub-regional rather than Europe-wide scale.

  4. Rheological properties in relation to molecular structure of quinoa starch.

    PubMed

    Li, Guantian; Zhu, Fan

    2018-07-15

    Quinoa starch granules are small (~0.5 - 3μm) with potentials for some food and other applications. To better exploit it as a new starch resource, this study investigates the steady shear and dynamic oscillatory properties of 9 quinoa starches varying in composition and structure. Steady shear analysis shows that the flow curves could be well described by 4 selected mathematic models. Temperature sweep analysis reveals that the quinoa starch encounters a 4-stage process including 2 phase transitions. Structure-function relationship analysis showed that composition as well as unit and internal chain length distribution of amylopectin have significant impact on the rheological properties (e.g., G' at 90°C) of quinoa starch. The roles of some individual unit chains and super-long unit chains of amylopectin in determining the rheological properties of quinoa starch were revealed. This study may stimulate further interest in understanding the structural basis of starch rheology. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Genetics, Molecular, and Proteomics Advances in Filamentous Fungi.

    PubMed

    Sharma Ghimire, Prakriti; Jin, Cheng

    2017-10-01

    Filamentous fungi play a dynamic role in health and the environment. In addition, their unique and complex hyphal structures are involved in their morphogenesis, integrity, synthesis, and degradation, according to environmental and physiological conditions and resource availability. However, in biotechnology, it has a great value in the production of enzymes, pharmaceuticals, and food ingredients. The beginning of nomenclature of overall fungi started in early 1990 after which the categorization, interior and exterior mechanism, function, molecular and genetics study took pace. This mini-review has emphasized some of the important aspects of filamentous fungi, their pattern of life cycle, history, and development of different strategic methods applied to exploit this unique organism. New trends and concepts that have been applied to overcome obstacle because of their basic structure related to genomics and systems biology has been presented. Furthermore, the future aspects and challenges that need to be deciphered to get a bigger and better picture of filamentous fungi have been discussed.

  6. Recent geophysical and geological research in Antarctica related to the assessment of petroleum resources and potential environmental hazards to their development

    USGS Publications Warehouse

    Behrendt, John C.; Splettstoesser, John F.; Dreschoff, Gisela A. M.

    1990-01-01

    During the 6-year negotiation of and adoption of the Convention on the Regulation of Antarctic Mineral Resources Activities on June 2, 1988, various countries have increased their attention to the possibility of exploitation of Antarctica's petroleum resources, which are covered by this treaty. However, there are no known petroleum resources in Antarctica, and scientific information is lacking to adequately assess any undiscovered resources or the possible environmental hazards to their development. Scientific research carried out in Antarctica since the International Geophysical Year (1957-1958) has provided a great deal of information on the geological framework of this ice-covered continent and its margin and has found general indications of the types of hazards that must be considered. Antarctica covers a vast area, and likely supergiant oil fields of the type to be exploited would be tiny (e.g., a few tens of kilometers across) in comparison. Any petroleum resources located in Antarctica will be found by applying the knowledge, techniques, and experience gained developing oil fields in other parts of the world and would, therefore, be other examples of general cases; in contrast, the Antarctic environment and its associated hazards must be considered unique.

  7. Natural Resources – Food Nexus: Food-Related Environmental Footprints in the Mediterranean Countries

    PubMed Central

    Lacirignola, Cosimo; Capone, Roberto; Debs, Philipp; El Bilali, Hamid; Bottalico, Francesco

    2014-01-01

    Immediate action is required in the Mediterranean to address environmental degradation that is mainly driven by consumption patterns. Increasing stress on biological and social systems is put by unsustainable consumption patterns. Food consumption patterns are important drivers of environment degradation. The objective of this review paper is to explore natural resources-food nexus in the Mediterranean region by highlighting the environmental footprints of the current consumption and production patterns. Secondary data from different sources such as FAOSTAT, the World Bank, Water Footprint Network (WFN), and Global Footprint Network were used to analyze the situation in 21 Mediterranean countries. The region faces many environmental challenges, e.g., land degradation, water scarcity, environment pollution, biodiversity loss, and climate change. The current consumption patterns imply high ecological, carbon, and water footprints of consumption and unfavorable national virtual-water balances. Food Balance Sheets data show that the contribution of vegetal and animal-based food product groups to food supply is variable among the Mediterranean countries. This has implications also in terms of the WF of food supply, which was calculated for Bosnia, Egypt, Italy, Morocco, and Turkey. The WF of the current diet resulted lower than that of the proposed Mediterranean one in the case of Italy. There is a strong scientific evidence supporting assumption that it is so also for other Mediterranean countries. The Mediterranean is characterized by a high resource use intensity that is further exacerbated by food losses and waste (FLW). In fact, FLW implies the loss of precious resources (water, land, energy) and inputs (fertilizers). Therefore, it is crucial to increase adherence to the traditional Mediterranean diet and to reduce FLW in order to foster transition to more sustainable food consumption patterns thus reducing pressure on the scarce resources of the Mediterranean region. PMID:25988125

  8. Natural resources - food nexus: food-related environmental footprints in the mediterranean countries.

    PubMed

    Lacirignola, Cosimo; Capone, Roberto; Debs, Philipp; El Bilali, Hamid; Bottalico, Francesco

    2014-01-01

    Immediate action is required in the Mediterranean to address environmental degradation that is mainly driven by consumption patterns. Increasing stress on biological and social systems is put by unsustainable consumption patterns. Food consumption patterns are important drivers of environment degradation. The objective of this review paper is to explore natural resources-food nexus in the Mediterranean region by highlighting the environmental footprints of the current consumption and production patterns. Secondary data from different sources such as FAOSTAT, the World Bank, Water Footprint Network (WFN), and Global Footprint Network were used to analyze the situation in 21 Mediterranean countries. The region faces many environmental challenges, e.g., land degradation, water scarcity, environment pollution, biodiversity loss, and climate change. The current consumption patterns imply high ecological, carbon, and water footprints of consumption and unfavorable national virtual-water balances. Food Balance Sheets data show that the contribution of vegetal and animal-based food product groups to food supply is variable among the Mediterranean countries. This has implications also in terms of the WF of food supply, which was calculated for Bosnia, Egypt, Italy, Morocco, and Turkey. The WF of the current diet resulted lower than that of the proposed Mediterranean one in the case of Italy. There is a strong scientific evidence supporting assumption that it is so also for other Mediterranean countries. The Mediterranean is characterized by a high resource use intensity that is further exacerbated by food losses and waste (FLW). In fact, FLW implies the loss of precious resources (water, land, energy) and inputs (fertilizers). Therefore, it is crucial to increase adherence to the traditional Mediterranean diet and to reduce FLW in order to foster transition to more sustainable food consumption patterns thus reducing pressure on the scarce resources of the Mediterranean region.

  9. Consequences of Food Restriction for Immune Defense, Parasite Infection, and Fitness in Monarch Butterflies.

    PubMed

    McKay, Alexa Fritzsche; Ezenwa, Vanessa O; Altizer, Sonia

    2016-01-01

    Organisms have a finite pool of resources to allocate toward multiple competing needs, such as development, reproduction, and enemy defense. Abundant resources can support investment in multiple traits simultaneously, but limited resources might promote trade-offs between fitness-related traits and immune defenses. We asked how food restriction at both larval and adult life stages of the monarch butterfly (Danaus plexippus) affected measures of immunity, fitness, and immune-fitness interactions. We experimentally infected a subset of monarchs with a specialist protozoan parasite to determine whether parasitism further affected these relationships and whether food restriction influenced the outcome of infection. Larval food restriction reduced monarch fitness measures both within the same life stage (e.g., pupal mass) as well as later in life (e.g., adult lifespan); adult food restriction further reduced adult lifespan. Larval food restriction lowered both hemocyte concentration and phenoloxidase activity at the larval stage, and the effects of larval food restriction on phenoloxidase activity persisted when immunity was sampled at the adult stage. Adult food restriction reduced only adult phenoloxidase activity but not hemocyte concentration. Parasite spore load decreased with one measure of larval immunity, but food restriction did not increase the probability of parasite infection. Across monarchs, we found a negative relationship between larval hemocyte concentration and pupal mass, and a trade-off between adult hemocyte concentration and adult life span was evident in parasitized female monarchs. Adult life span increased with phenoloxidase activity in some subsets of monarchs. Our results emphasize that food restriction can alter fitness and immunity across multiple life stages. Understanding the consequences of resource limitation for immune defense is therefore important for predicting how increasing constraints on wildlife resources will affect fitness and resistance to natural enemies.

  10. Exploitation of Food Industry Waste for High-Value Products.

    PubMed

    Ravindran, Rajeev; Jaiswal, Amit K

    2016-01-01

    A growing global population leads to an increasing demand for food production and the processing industry associated with it and consequently the generation of large amounts of food waste. This problem is intensified due to slow progress in the development of effective waste management strategies and measures for the proper treatment and disposal of waste. Food waste is a reservoir of complex carbohydrates, proteins, lipids, and nutraceuticals and can form the raw materials for commercially important metabolites. The current legislation on food waste treatment prioritises the prevention of waste generation and least emphasises disposal. Recent valorisation studies for food supply chain waste opens avenues to the production of biofuels, enzymes, bioactive compounds, biodegradable plastics, and nanoparticles among many other molecules. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Application of the WHO keys of safer food to improve food handling practices of food vendors in a poor resource community in Ghana.

    PubMed

    Donkor, Eric S; Kayang, Boniface B; Quaye, Jonathan; Akyeh, Moses L

    2009-11-01

    Data was collected from food vendors in a poor resource community in Ghana, which showed that the vendors constituted an important source of oro-faecal transmission. Following this, the WHO five keys of safer food were utilized in an evidence based training programme for the vendors to improve their food handling practices. Impact assessment of the food safety training showed that 67.6% of the vendors had acquired some knowledge from the workshop and were putting it into practice. Lack of food safety equipment was a major hinderance to behavioral change among the vendors as far food handling practices are concerned.

  12. Producing and Scrounging during Problem Based Learning

    ERIC Educational Resources Information Center

    Vickery, William L.

    2013-01-01

    When problem based learning occurs in a social context it is open to a common social behaviour, scrounging. In the animal behaviour literature, scroungers do not attempt to find resources themselves but rather exploit resources found by other group members (referred to as producers). We know from studies of animal behaviour (including humans) that…

  13. Using Authentic Resources in Teaching French. Teaching Languages, 4.

    ERIC Educational Resources Information Center

    Jones, Barry, Ed.

    A collection of papers gives ideas for exploitation of resources easily available to the language teacher. Although the papers apply specifically to French instruction, the ideas may be of interest to all language teachers. "Realia in the Classroom" (Norman Hill) concerns the contribution to language instruction of such materials as containers,…

  14. The FLEXGene repository: exploiting the fruits of the genome projects by creating a needed resource to face the challenges of the post-genomic era.

    PubMed

    Brizuela, Leonardo; Richardson, Aaron; Marsischky, Gerald; Labaer, Joshua

    2002-01-01

    Thanks to the results of the multiple completed and ongoing genome sequencing projects and to the newly available recombination-based cloning techniques, it is now possible to build gene repositories with no precedent in their composition, formatting, and potential. This new type of gene repository is necessary to address the challenges imposed by the post-genomic era, i.e., experimentation on a genome-wide scale. We are building the FLEXGene (Full Length EXpression-ready) repository. This unique resource will contain clones representing the complete ORFeome of different organisms, including Homo sapiens as well as several pathogens and model organisms. It will consist of a comprehensive, characterized (sequence-verified), and arrayed gene repository. This resource will allow full exploitation of the genomic information by enabling genome-wide scale experimentation at the level of functional/phenotypic assays as well as at the level of protein expression, purification, and analysis. Here we describe the rationale and construction of this resource and focus on the data obtained from the Saccharomyces cerevisiae project.

  15. Online Resources for Teaching Units on: Ecological Footprint of Human Food

    ERIC Educational Resources Information Center

    Marrocco, Aldo T.

    2011-01-01

    The modern food system involves high consumption of natural resources and other forms of environmental degradation. This paper is a presentation of internet resources such as scientific contributions, graphics, tables, images, animations and interactive atlases that can help to teach this subject. The discussion contains some subjects considered…

  16. Theme--Achieving 2020. Goal 3: All Students Are Conversationally Literate in Agriculture, Food, Fiber, and Natural Resource Systems.

    ERIC Educational Resources Information Center

    Trexler, Cary, Ed.

    2000-01-01

    Nine theme articles focus on the need for students to be conversationally literate about agriculture, food, fiber, and natural resources systems. Discusses the definition of conversational literacy, the human and institutional resources needed, and exemplary models for promoting literacy. (JOW)

  17. Consumer-resource stoichiometry in detritus-based streams

    Treesearch

    Wyatt F. Cross; Jonathan P. Benstead; Amy D. Rosemond; J. Bruce Wallace

    2003-01-01

    Stoichiometric relationships between consumers and resources in detritus-based ecosystems have received little attention, despite the importance of detritus in most food webs. We analysed carbon (C), nitrogen (N), and phosphorus (P) content of invertebrate consumers, and basal food resources in two forested headwater streams (one reference and the other nutrient-...

  18. Projecting changes in the distribution and productivity of living marine resources: A critical review of the suite of modelling approaches used in the large European project VECTORS

    NASA Astrophysics Data System (ADS)

    Peck, Myron A.; Arvanitidis, Christos; Butenschön, Momme; Canu, Donata Melaku; Chatzinikolaou, Eva; Cucco, Andrea; Domenici, Paolo; Fernandes, Jose A.; Gasche, Loic; Huebert, Klaus B.; Hufnagl, Marc; Jones, Miranda C.; Kempf, Alexander; Keyl, Friedemann; Maar, Marie; Mahévas, Stéphanie; Marchal, Paul; Nicolas, Delphine; Pinnegar, John K.; Rivot, Etienne; Rochette, Sébastien; Sell, Anne F.; Sinerchia, Matteo; Solidoro, Cosimo; Somerfield, Paul J.; Teal, Lorna R.; Travers-Trolet, Morgan; van de Wolfshaar, Karen E.

    2018-02-01

    We review and compare four broad categories of spatially-explicit modelling approaches currently used to understand and project changes in the distribution and productivity of living marine resources including: 1) statistical species distribution models, 2) physiology-based, biophysical models of single life stages or the whole life cycle of species, 3) food web models, and 4) end-to-end models. Single pressures are rare and, in the future, models must be able to examine multiple factors affecting living marine resources such as interactions between: i) climate-driven changes in temperature regimes and acidification, ii) reductions in water quality due to eutrophication, iii) the introduction of alien invasive species, and/or iv) (over-)exploitation by fisheries. Statistical (correlative) approaches can be used to detect historical patterns which may not be relevant in the future. Advancing predictive capacity of changes in distribution and productivity of living marine resources requires explicit modelling of biological and physical mechanisms. New formulations are needed which (depending on the question) will need to strive for more realism in ecophysiology and behaviour of individuals, life history strategies of species, as well as trophodynamic interactions occurring at different spatial scales. Coupling existing models (e.g. physical, biological, economic) is one avenue that has proven successful. However, fundamental advancements are needed to address key issues such as the adaptive capacity of species/groups and ecosystems. The continued development of end-to-end models (e.g., physics to fish to human sectors) will be critical if we hope to assess how multiple pressures may interact to cause changes in living marine resources including the ecological and economic costs and trade-offs of different spatial management strategies. Given the strengths and weaknesses of the various types of models reviewed here, confidence in projections of changes in the distribution and productivity of living marine resources will be increased by assessing model structural uncertainty through biological ensemble modelling.

  19. Balancing water resource conservation and food security in China

    PubMed Central

    Dalin, Carole; Qiu, Huanguang; Hanasaki, Naota; Mauzerall, Denise L.; Rodriguez-Iturbe, Ignacio

    2015-01-01

    China’s economic growth is expected to continue into the next decades, accompanied by sustained urbanization and industrialization. The associated increase in demand for land, water resources, and rich foods will deepen the challenge of sustainably feeding the population and balancing agricultural and environmental policies. We combine a hydrologic model with an economic model to project China’s future food trade patterns and embedded water resources by 2030 and to analyze the effects of targeted irrigation reductions on this system, notably on national agricultural water consumption and food self-sufficiency. We simulate interprovincial and international food trade with a general equilibrium welfare model and a linear programming optimization, and we obtain province-level estimates of commodities’ virtual water content with a hydrologic model. We find that reducing irrigated land in regions highly dependent on scarce river flow and nonrenewable groundwater resources, such as Inner Mongolia and the greater Beijing area, can improve the efficiency of agriculture and trade regarding water resources. It can also avoid significant consumption of irrigation water across China (up to 14.8 km3/y, reduction by 14%), while incurring relatively small decreases in national food self-sufficiency (e.g., by 3% for wheat). Other researchers found that a national, rather than local, water policy would have similar effects on food production but would only reduce irrigation water consumption by 5%. PMID:25825748

  20. Balancing water resource conservation and food security in China.

    PubMed

    Dalin, Carole; Qiu, Huanguang; Hanasaki, Naota; Mauzerall, Denise L; Rodriguez-Iturbe, Ignacio

    2015-04-14

    China's economic growth is expected to continue into the next decades, accompanied by sustained urbanization and industrialization. The associated increase in demand for land, water resources, and rich foods will deepen the challenge of sustainably feeding the population and balancing agricultural and environmental policies. We combine a hydrologic model with an economic model to project China's future food trade patterns and embedded water resources by 2030 and to analyze the effects of targeted irrigation reductions on this system, notably on national agricultural water consumption and food self-sufficiency. We simulate interprovincial and international food trade with a general equilibrium welfare model and a linear programming optimization, and we obtain province-level estimates of commodities' virtual water content with a hydrologic model. We find that reducing irrigated land in regions highly dependent on scarce river flow and nonrenewable groundwater resources, such as Inner Mongolia and the greater Beijing area, can improve the efficiency of agriculture and trade regarding water resources. It can also avoid significant consumption of irrigation water across China (up to 14.8 km(3)/y, reduction by 14%), while incurring relatively small decreases in national food self-sufficiency (e.g., by 3% for wheat). Other researchers found that a national, rather than local, water policy would have similar effects on food production but would only reduce irrigation water consumption by 5%.

  1. Investigation and Evaluation of Groundwater Resources of Juxian

    NASA Astrophysics Data System (ADS)

    Xinyi, Li; Wanglin, Li; Xiaojiao, Zhang; Deling, Zhu; Huadan, Yan

    2018-03-01

    The investigation and evaluation of groundwater resources refers to the analysis of groundwater quantity, quality, spatial-temporal property and exploitation status. Based on the collected data and field investigation, the groundwater resources in plain and hilly area of Juxian were calculated by replenishment method, discharge method and comprehensive infiltration coefficient method, and the groundwater quality was analyzed and evaluated. The conclusions are as follows: (1) The amount of groundwater resources is 224.940 million m3/a, including 89.585 million m3/a of plain area and 142.523 million m3/a of hilly area respectively. (2) The allowable yield of groundwater is about 162.948 million m3/a, in which the amounts in the plain area and the hilly area are 74 .585million m3/a and 88.363 million m3/a, respectively. (3) The pH value of groundwater ranges from 6.5∼7.5 and the degree of mineralization of groundwater was lower than 1 g/L at most. In addition, the total hardness varies from 150 mg/L to 450 mg/L in plain area and 300 mg/L to 550 mg/L in hilly area, respectively. The investigation and evaluation of groundwater resources was of great significance in ensuring the sustainable development of groundwater resources, establishing the scheme of groundwater resources exploitation and utilization.

  2. 21 CFR 212.10 - What personnel and resources must I have?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 4 2010-04-01 2010-04-01 false What personnel and resources must I have? 212.10 Section 212.10 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR POSITRON EMISSION TOMOGRAPHY DRUGS (Eff...

  3. 21 CFR 212.10 - What personnel and resources must I have?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 4 2011-04-01 2011-04-01 false What personnel and resources must I have? 212.10 Section 212.10 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS: GENERAL CURRENT GOOD MANUFACTURING PRACTICE FOR POSITRON EMISSION TOMOGRAPHY DRUGS...

  4. Resource for Evaluating the Economic Impact of Local Food System Initiatives

    ERIC Educational Resources Information Center

    Jablonski, Becca B. R.; O'Hara, Jeffrey K.; McFadden, Dawn Thilmany; Tropp, Debra

    2016-01-01

    Local food system stakeholders are confronted with challenges when attempting to ascertain the economic impacts of food system investments. The U.S. Department of Agriculture Agricultural Marketing Service commissioned a team of economists to develop a resource to provide support to stakeholders interested in understanding the economic impacts of…

  5. World Food Security and Insecurity, 1984-2000.

    ERIC Educational Resources Information Center

    Farrell, Kenneth R.

    Effective economic demand, rather than resource constraints, will continue to be the dominant limiting factor in improving the security of world food supplies between now and the year 2000. The global demand for food will continue to grow but the rate of growth is declining in virtually all regions, easing the pressure on agricultural resources.…

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

    PubMed Central

    Morissette, Lyne; Christensen, Villy; Pauly, Daniel

    2012-01-01

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

  7. Explore or Exploit? A Generic Model and an Exactly Solvable Case

    NASA Astrophysics Data System (ADS)

    Gueudré, Thomas; Dobrinevski, Alexander; Bouchaud, Jean-Philippe

    2014-02-01

    Finding a good compromise between the exploitation of known resources and the exploration of unknown, but potentially more profitable choices, is a general problem, which arises in many different scientific disciplines. We propose a stylized model for these exploration-exploitation situations, including population or economic growth, portfolio optimization, evolutionary dynamics, or the problem of optimal pinning of vortices or dislocations in disordered materials. We find the exact growth rate of this model for treelike geometries and prove the existence of an optimal migration rate in this case. Numerical simulations in the one-dimensional case confirm the generic existence of an optimum.

  8. Explore or exploit? A generic model and an exactly solvable case.

    PubMed

    Gueudré, Thomas; Dobrinevski, Alexander; Bouchaud, Jean-Philippe

    2014-02-07

    Finding a good compromise between the exploitation of known resources and the exploration of unknown, but potentially more profitable choices, is a general problem, which arises in many different scientific disciplines. We propose a stylized model for these exploration-exploitation situations, including population or economic growth, portfolio optimization, evolutionary dynamics, or the problem of optimal pinning of vortices or dislocations in disordered materials. We find the exact growth rate of this model for treelike geometries and prove the existence of an optimal migration rate in this case. Numerical simulations in the one-dimensional case confirm the generic existence of an optimum.

  9. SMART: A Spatially Explicit Bio-Economic Model for Assessing and Managing Demersal Fisheries, with an Application to Italian Trawlers in the Strait of Sicily

    PubMed Central

    Russo, Tommaso; Parisi, Antonio; Garofalo, Germana; Gristina, Michele; Cataudella, Stefano; Fiorentino, Fabio

    2014-01-01

    Management of catches, effort and exploitation pattern are considered the most effective measures to control fishing mortality and ultimately ensure productivity and sustainability of fisheries. Despite the growing concerns about the spatial dimension of fisheries, the distribution of resources and fishing effort in space is seldom considered in assessment and management processes. Here we propose SMART (Spatial MAnagement of demersal Resources for Trawl fisheries), a tool for assessing bio-economic feedback in different management scenarios. SMART combines information from different tasks gathered within the European Data Collection Framework on fisheries and is composed of: 1) spatial models of fishing effort, environmental characteristics and distribution of demersal resources; 2) an Artificial Neural Network which captures the relationships among these aspects in a spatially explicit way and uses them to predict resources abundances; 3) a deterministic module which analyzes the size structure of catches and the associated revenues, according to different spatially-based management scenarios. SMART is applied to demersal fishery in the Strait of Sicily, one of the most productive fisheries of the Mediterranean Sea. Three of the main target species are used as proxies for the whole range exploited by trawlers. After training, SMART is used to evaluate different management scenarios, including spatial closures, using a simulation approach that mimics the recent exploitation patterns. Results evidence good model performance, with a noteworthy coherence and reliability of outputs for the different components. Among others, the main finding is that a partial improvement in resource conditions can be achieved by means of nursery closures, even if the overall fishing effort in the area remains stable. Accordingly, a series of strategically designed areas of trawling closures could significantly improve the resource conditions of demersal fisheries in the Strait of Sicily, also supporting sustainable economic returns for fishermen if not applied simultaneously for different species. PMID:24465971

  10. Dance communication affects consistency, but not breadth, of resource use in pollen-foraging honey bees.

    PubMed

    Donaldson-Matasci, Matina; Dornhaus, Anna

    2014-01-01

    In groups of cooperatively foraging individuals, communication may improve the group's performance by directing foraging effort to where it is most useful. Honey bees (Apis mellifera) use a specialized dance to communicate the location of floral resources. Because honey bees dance longer for more rewarding resources, communication may shift the colony's foraging effort towards higher quality resources, and thus narrow the spectrum of resource types used. To test the hypothesis that dance communication changes how much honey bee colonies specialize on particular resources, we manipulated their ability to communicate location, and assessed the relative abundance of different pollen taxa they collected. This was repeated across five natural habitats that differed in floral species richness and spatial distribution. Contrary to expectation, impairing communication did not change the number or diversity of pollen (resource) types used by individual colonies per day. However, colonies with intact dance communication were more consistent in their resource use, while those with impaired communication were more likely to collect rare, novel pollen types. This suggests that communication plays an important role in shaping how much colonies invest in exploring new resources versus exploiting known ones. Furthermore, colonies that did more exploration also tended to collect less pollen overall, but only in environments with greater floral abundance per patch. In such environments, the ability to effectively exploit highly rewarding resources may be especially important-and dance communication may help colonies do just that. This could help explain how communication benefits honey bee colonies, and also why it does so only under certain environmental conditions.

  11. Dance Communication Affects Consistency, but Not Breadth, of Resource Use in Pollen-Foraging Honey Bees

    PubMed Central

    Donaldson-Matasci, Matina; Dornhaus, Anna

    2014-01-01

    In groups of cooperatively foraging individuals, communication may improve the group’s performance by directing foraging effort to where it is most useful. Honey bees (Apis mellifera) use a specialized dance to communicate the location of floral resources. Because honey bees dance longer for more rewarding resources, communication may shift the colony’s foraging effort towards higher quality resources, and thus narrow the spectrum of resource types used. To test the hypothesis that dance communication changes how much honey bee colonies specialize on particular resources, we manipulated their ability to communicate location, and assessed the relative abundance of different pollen taxa they collected. This was repeated across five natural habitats that differed in floral species richness and spatial distribution. Contrary to expectation, impairing communication did not change the number or diversity of pollen (resource) types used by individual colonies per day. However, colonies with intact dance communication were more consistent in their resource use, while those with impaired communication were more likely to collect rare, novel pollen types. This suggests that communication plays an important role in shaping how much colonies invest in exploring new resources versus exploiting known ones. Furthermore, colonies that did more exploration also tended to collect less pollen overall, but only in environments with greater floral abundance per patch. In such environments, the ability to effectively exploit highly rewarding resources may be especially important–and dance communication may help colonies do just that. This could help explain how communication benefits honey bee colonies, and also why it does so only under certain environmental conditions. PMID:25271418

  12. Mixotrophy and intraguild predation - dynamic consequences of shifts between food web motifs

    NASA Astrophysics Data System (ADS)

    Karnatak, Rajat; Wollrab, Sabine

    2017-06-01

    Mixotrophy is ubiquitous in microbial communities of aquatic systems with many flagellates being able to use autotroph as well as heterotroph pathways for energy acquisition. The usage of one over the other pathway is associated with resource availability and the coupling of alternative pathways has strong implications for system stability. We investigated the impact of dominance of different energy pathways related to relative resource availability on system dynamics in the setting of a tritrophic food web motif. This motif consists of a mixotroph feeding on a purely autotroph species while competing for a shared resource. In addition, the autotroph can use an additional exclusive food source. By changing the relative abundance of shared vs. exclusive food source, we shift the food web motif from an intraguild predation motif to a food chain motif. We analyzed the dependence of system dynamics on absolute and relative resource availability. In general, the system exhibits a transition from stable to oscillatory dynamics with increasing nutrient availability. However, this transition occurs at a much lower nutrient level for the food chain in comparison to the intraguild predation motif. A similar transition is also observed with variations in the relative abundance of food sources for a range of nutrient levels. We expect this shift in food web motifs to occur frequently in microbial communities and therefore the results from our study are highly relevant for natural systems.

  13. An extended environmental input-output lifecycle assessment model to study the urban food-energy-water nexus

    NASA Astrophysics Data System (ADS)

    Sherwood, John; Clabeaux, Raeanne; Carbajales-Dale, Michael

    2017-10-01

    We developed a physically-based environmental account of US food production systems and integrated these data into the environmental-input-output life cycle assessment (EIO-LCA) model. The extended model was used to characterize the food, energy, and water (FEW) intensities of every US economic sector. The model was then applied to every Bureau of Economic Analysis metropolitan statistical area (MSA) to determine their FEW usages. The extended EIO-LCA model can determine the water resource use (kGal), energy resource use (TJ), and food resource use in units of mass (kg) or energy content (kcal) of any economic activity within the United States. We analyzed every economic sector to determine its FEW intensities per dollar of economic output. This data was applied to each of the 382 MSAs to determine their total and per dollar of GDP FEW usages by allocating MSA economic production to the corresponding FEW intensities of US economic sectors. Additionally, a longitudinal study was performed for the Los Angeles-Long Beach-Anaheim, CA, metropolitan statistical area to examine trends from this singular MSA and compare it to the overall results. Results show a strong correlation between GDP and energy use, and between food and water use across MSAs. There is also a correlation between GDP and greenhouse gas emissions. The longitudinal study indicates that these correlations can shift alongside a shifting industrial composition. Comparing MSAs on a per GDP basis reveals that central and southern California tend to be more resource intensive than many other parts of the country, while much of Florida has abnormally low resource requirements. Results of this study enable a more complete understanding of food, energy, and water as key ingredients to a functioning economy. With the addition of the food data to the EIO-LCA framework, researchers will be able to better study the food-energy-water nexus and gain insight into how these three vital resources are interconnected. Applying this extended model to MSAs has demonstrated that all three resources are important to a MSA’s vitality, though the exact proportion of each resource may differ across urban areas.

  14. Urbanization, Extreme Climate Hazards and Food, Energy Water Security

    NASA Astrophysics Data System (ADS)

    Romero-Lankao, P.; Davidson, D.; McPhearson, T.

    2016-12-01

    Research is urgently needed that incorporates the interconnected nature of three critical resources supporting our cities: food, energy and water. Cities are increasing demands for food, water and energy resources that in turn stress resource supplies, creating risks of negative impacts to human and ecological wellbeing. Simultaneously, shifts in climatic conditions, including extremes such as floods, heat, and droughts, threaten the sustainable availability of adequate quantities and qualities of food, energy and water (FEW) resources needed for resilient cities and ecosystems. These resource flows cannot be treated in isolation simply because they are interconnected: shifts in food, energy or water dynamics in turn affect the others, affecting the security of the whole - i.e., FEW nexus security. We present a framework to examine the dynamic interactions of urbanization, FEW nexus security and extreme hazard risks, with two overarching research questions: Do existing and emerging actions intended to enhance a population's food, water and energy security have the capacity to ensure FEW nexus security in the face of changing climate and urban development conditions? Can we identify a common set of social, ecological and technological conditions across a diversity of urban-regions that support the emergence of innovations that can lead to structural transformations for FEW nexus security?

  15. Determinants of emigration and their impact on survival during dispersal in fox and jackal populations

    PubMed Central

    Kapota, Dror; Dolev, Amit; Bino, Gilad; Yosha, Dotan; Guter, Amichai; King, Roni; Saltz, David

    2016-01-01

    Animals disperse in response to poor resource conditions as a strategy of escaping harsh competition and stress, but may also disperse under good resource conditions, as these provide better chances of surviving dispersal and gaining fitness benefits such as avoiding kin competition and inbreeding. Individual traits should mediate the effect of resources, yielding a complex condition-dependent dispersal response. We investigated how experimental food reductions in a food-rich environment around poultry-growing villages interact with individual-traits (age, gender, body-mass) in two sympatric canids, red foxes and golden jackals, to jointly affect emigration propensity and survival during dispersal. Sub-adult foxes emigrated more frequently from the food-rich habitat than from the pristine, food-limited habitat, while adult foxes showed the opposite trend. During dispersal, adults exhibited lower survival while sub-adults did not experience additional mortality costs. Although fox mortality rates increased in response to food reduction, dispersal remained unchanged, while jackals showed strong dispersal response in two of the three repetitions. Jackal survival under food reduction was lowest for the dispersing individuals. While resources are an important dispersal determinant, different age classes and species experience the same resource environment differently and consequently have different motivations, yielding different dispersal responses and consequences. PMID:27050564

  16. Smallholder Irrigation and Crop Diversification under Climate Change in sub-Saharan Africa: Evidence and Potential for Simultaneous Food Security, Adaptation, and Mitigation

    NASA Astrophysics Data System (ADS)

    Naylor, R.; Burney, J. A.; Postel, S.

    2011-12-01

    The poorest populations in sub-Saharan Africa live in rural areas and depend on smallholder agricultural production for their livelihoods. Over 90% of all farmed area in Sub-Saharan Africa is rainfed, with crop production centering on 3-5 months of rainfall. Rapid population growth is reducing land per capita ratios, and low yields for staple crops make food security an increasingly challenging goal. Malnutrition, most noticeable among children, peaks during the dry season. Recent data on aggregate economic growth and investment in Africa hide these patterns of seasonal hunger and income disparity. Perhaps most perversely, smallholder farmers in the dry tropical regions of sub-Saharan Africa are (and will continue to be) some of the earliest and hardest hit by climate change. Our research focuses on the role distributed, small-scale irrigation can play in food security and climate change adaptation in sub-Saharan Africa. As Asia's agricultural success has demonstrated, irrigation, when combined with the availability of inputs (fertilizer) and improved crop varieties, can enable year-round production, growth in rural incomes, and a dramatic reduction in hunger. The situation in Africa is markedly different: agroecological conditions are far more heterogeneous than in Asia and evaporation rates are relatively high; most smallholders lack access to fertilizers; and market integration is constrained by infrastructure, information, and private sector incentives. Yet from a resource perspective, national- and regional-level estimates suggest that Internal Renewable Water Resources (IRWR) are nowhere near fully exploited in Sub-Saharan Africa -- even in the Sudano-Sahel, which is considered to be one of the driest regions of the continent. Irrigation can thus be implemented on a much larger scale sustainably. We will present (a) results from controlled, experimental field studies of solar-powered drip irrigation systems in the rural Sudano-Sahel region of West Africa. We have shown that such systems can be implemented in a cost-competitive and environmentally responsible manner, with significant and sustained impact on livelihoods. These findings will be coupled with (b) case studies of successful and failed irrigation projects across the continent that reveal technical and institutional requirements for success; and (c) regional and continental data that quantify the larger-scale food security, development, adaptation, and mitigation potentials of these types of smallholder systems.

  17. [Distribution Characteristics and Source of Fluoride in Groundwater in Lower Plain Area of North China Plain: A Case Study in Nanpi County].

    PubMed

    Kong, Xiao-le; Wang, Shi-qin; Zhao, Huan; Yuan, Rui-qiang

    2015-11-01

    There is an obvious regional contradiction between water resources and agricultural produce in lower plain area of North China, however, excessive fluorine in deep groundwater further limits the use of regional water resources. In order to understand the spatial distribution characteristics and source of F(-) in groundwater, study was carried out in Nanpi County by field survey and sampling, hydrogeochemical analysis and stable isotopes methods. The results showed that the center of low fluoride concentrations of shallow groundwater was located around reservoir of Dalang Lake, and centers of high fluoride concentrations were located in southeast and southwest of the study area. The region with high fluoride concentration was consistent with the over-exploitation region of deep groundwater. Point source pollution of subsurface drainage and non-point source of irrigation with deep groundwater in some regions were the main causes for the increasing F(-) concentrations of shallow groundwater in parts of the sampling sites. Rock deposition and hydrogeology conditions were the main causes for the high F(-) concentrations (1.00 mg x L(-1), threshold of drinking water quality standard in China) in deep groundwater. F(-) released from clay minerals into the water increased the F(-) concentrations in deep groundwater because of over-exploitation. With the increasing exploitation and utilization of brackish shallow groundwater and the compressing and restricting of deep groundwater exploitation, the water environment in the middle and east lower plain area of North China will undergo significant change, and it is important to identify the distribution and source of F(-) in surface water and groundwater for reasonable development and use of water resources in future.

  18. Demographic and growth responses of a guerrilla and a phalanx perennial grass in competitive mixtures

    USGS Publications Warehouse

    Humphrey, L. David; Pyke, David A.

    1998-01-01

    The advantages of guerrilla and phalanx growth for the guerrilla Elymus lanceolatus ssp. lanceolatus and phalanx E. l. ssp. wawawaiensis were evaluated over 2 years in two taxon mixtures with a range of densities of each subspecies and under two levels of watering. Ramet numbers and biomass of the guerrilla subspecies were higher than those of the phalanx grass in the first year but in the second year declined greatly, while the phalanx grass showed no change in biomass and an increase in ramet numbers. High neighbour densities affected the phalanx subspecies more strongly than the guerrilla subspecies in the first year, but in the second year there were few differences between subspecies. Biomass of the guerrilla grass remained greater than that of the phalanx grass but ramet numbers were similar in the second year. For both subspecies in both years, probability of flowering decreased at higher neighbour densities, indicating adaptation for competitive ability. In the first year, biomass was more strongly reduced by densities than flowering was, but in the second year, when crowding was apparently greater, flowering was more severely affected. Genet survival was high and similar for both subspecies. The presumed advantage of guerrilla subspecies in exploiting open space was supported. The guerrilla grass exploited resources more quickly in the first year by faster growth and greater ramet production, but its biomass, ramet numbers and rhizome growth, and thus its advantage, were reduced in the second year. The phalanx subspecies had slower growth, produced more ramets in later years, and delayed flowering until later years. Although less able to exploit open resources, it appeared adapted to more stressful conditions, and may be able to exploit temporal resource pulses more effectively.

  19. Energy Portfolio Assessment Tool (EPAT): Sustainable Energy Planning Using the WEF Nexus Approach - Texas Case Study

    NASA Astrophysics Data System (ADS)

    Mroue, A. M.

    2017-12-01

    The future energy portfolio at the national and subnational levels should consider its impact on water resources and environment. Although energy resources are the main contributors to the national economic growth, these resources must not exploit other primary natural resources. A study of the connections between energy and natural systems, such as water, environment and land is required prior to proceeding to energy development. Policy makers are in need of a tool quantifying the interlinkages across energy, water and the environment, while demonstrating the consequent trade-offs across the nexus systems. The Energy Portfolio Assessment Tool (EPAT) is a tool that enables the policy maker to create different energy portfolio scenarios with various energy and electricity sources, and evaluate the scenario's sustainability environmentally and economically. The Water-Energy-Food nexus systematic approach is the foundation of the EPAT framework. The research evaluates the impact of the current and projected Texas energy portfolios on water and the environment, taking into consideration energy production, electricity generation and policy change. The three scenarios to be assessed include EIA projections for energy production, and EIA projections for electricity generation with and without the Clean Power Plan (CPP). Each scenario is accompanied by tradeoffs across water, land, emissions, energy revenue and electricity cost. The CPP succeeds in mitigating the emissions of the electricity portfolio, but leads to an increase in water consumption and land use. The cost of electricity generation is almost identical with and without environmental conservation. Revenue from energy production increased, but results are majorly influenced by commodity price. Therefore, conservation policies should move from the silo to the nexus mentality to avoid unintended consequences as improving one part of the nexus could end up worsening the other parts.

  20. Revenue-sharing clubs provide economic insurance and incentives for sustainability in common-pool resource systems.

    PubMed

    Tilman, Andrew R; Levin, Simon; Watson, James R

    2018-06-05

    Harvesting behaviors of natural resource users, such as farmers, fishermen and aquaculturists, are shaped by season-to-season and day-to-day variability, or in other words risk. Here, we explore how risk-mitigation strategies can lead to sustainable use and improved management of common-pool natural resources. Over-exploitation of unmanaged natural resources, which lowers their long-term productivity, is a central challenge facing societies. While effective top-down management is a possible solution, it is not available if the resource is outside the jurisdictional bounds of any management entity, or if existing institutions cannot effectively impose sustainable-use rules. Under these conditions, alternative approaches to natural resource governance are required. Here, we study revenue-sharing clubs as a mechanism by which resource users can mitigate their income volatility and importantly, as a co-benefit, are also incentivized to reduce their effort, leading to reduced over-exploitation and improved resource governance. We use game theoretic analyses and agent-based modeling to determine the conditions in which revenue-sharing can be beneficial for resource management as well as resource users. We find that revenue-sharing agreements can emerge and lead to improvements in resource management when there is large variability in production/revenue and when this variability is uncorrelated across members of the revenue-sharing club. Further, we show that if members of the revenue-sharing collective can sell their product at a price premium, then the range of ecological and economic conditions under which revenue-sharing can be a tool for management greatly expands. These results have implications for the design of bottom-up management, where resource users themselves are incentivized to operate in ecologically sustainable and economically advantageous ways. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Comparing urban solid waste recycling from the viewpoint of urban metabolism based on physical input-output model: A case of Suzhou in China

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

    Liang Sai, E-mail: liangsai09@gmail.com; Zhang Tianzhu, E-mail: zhangtz@mail.tsinghua.edu.cn

    Highlights: Black-Right-Pointing-Pointer Impacts of solid waste recycling on Suzhou's urban metabolism in 2015 are analyzed. Black-Right-Pointing-Pointer Sludge recycling for biogas is regarded as an accepted method. Black-Right-Pointing-Pointer Technical levels of reusing scrap tires and food wastes should be improved. Black-Right-Pointing-Pointer Other fly ash utilization methods should be exploited. Black-Right-Pointing-Pointer Secondary wastes from reusing food wastes and sludge should be concerned. - Abstract: Investigating impacts of urban solid waste recycling on urban metabolism contributes to sustainable urban solid waste management and urban sustainability. Using a physical input-output model and scenario analysis, urban metabolism of Suzhou in 2015 is predicted and impactsmore » of four categories of solid waste recycling on urban metabolism are illustrated: scrap tire recycling, food waste recycling, fly ash recycling and sludge recycling. Sludge recycling has positive effects on reducing all material flows. Thus, sludge recycling for biogas is regarded as an accepted method. Moreover, technical levels of scrap tire recycling and food waste recycling should be improved to produce positive effects on reducing more material flows. Fly ash recycling for cement production has negative effects on reducing all material flows except solid wastes. Thus, other fly ash utilization methods should be exploited. In addition, the utilization and treatment of secondary wastes from food waste recycling and sludge recycling should be concerned.« less

  2. China Report, Economic Affairs

    DTIC Science & Technology

    1985-01-26

    Revenue, Expenditures 83 ENERGY Briefs Tianjin Methane Pits 84 - c - MINERAL RESOURCES PRC Journal on Stepping Up Exploitation of Mines (Li Peilin ...Huayun, Zhan Jingwu, Yao Xia, Lin Yinghai, Hou Zhiying, Song [name indis- tinct], Li Baoguang, Zhang Shude, Hu Tingji, and Hao Fuhong attended the...10, 5 Oct 84 pp 4-6 [Article by Li Peilin [621 3099 2651]: "A Probe into the Policy of Stepping Up the Exploitation of Mines"] [Text] Recently

  3. Computing and Communications Infrastructure for Network-Centric Warfare: Exploiting COTS, Assuring Performance

    DTIC Science & Technology

    2004-06-01

    remote databases, has seen little vendor acceptance. Each database ( Oracle , DB2, MySQL , etc.) has its own client- server protocol. Therefore each...existing standards – SQL , X.500/LDAP, FTP, etc. • View information dissemination as selective replication – State-oriented vs . message-oriented...allowing the 8 application to start. The resource management system would serve as a broker to the resources, making sure that resources are not

  4. Improving information retrieval with multiple health terminologies in a quality-controlled gateway.

    PubMed

    Soualmia, Lina F; Sakji, Saoussen; Letord, Catherine; Rollin, Laetitia; Massari, Philippe; Darmoni, Stéfan J

    2013-01-01

    The Catalog and Index of French-language Health Internet resources (CISMeF) is a quality-controlled health gateway, primarily for Web resources in French (n=89,751). Recently, we achieved a major improvement in the structure of the catalogue by setting-up multiple terminologies, based on twelve health terminologies available in French, to overcome the potential weakness of the MeSH thesaurus, which is the main and pivotal terminology we use for indexing and retrieval since 1995. The main aim of this study was to estimate the added-value of exploiting several terminologies and their semantic relationships to improve Web resource indexing and retrieval in CISMeF, in order to provide additional health resources which meet the users' expectations. Twelve terminologies were integrated into the CISMeF information system to set up multiple-terminologies indexing and retrieval. The same sets of thirty queries were run: (i) by exploiting the hierarchical structure of the MeSH, and (ii) by exploiting the additional twelve terminologies and their semantic links. The two search modes were evaluated and compared. The overall coverage of the multiple-terminologies search mode was improved by comparison to the coverage of using the MeSH (16,283 vs. 14,159) (+15%). These additional findings were estimated at 56.6% relevant results, 24.7% intermediate results and 18.7% irrelevant. The multiple-terminologies approach improved information retrieval. These results suggest that integrating additional health terminologies was able to improve recall. Since performing the study, 21 other terminologies have been added which should enable us to make broader studies in multiple-terminologies information retrieval.

  5. Soil aggregation as mechanism for understanding the roles of soil biota in the sustainable usage of natural resources

    USDA-ARS?s Scientific Manuscript database

    Global food insecurity and rapidly diminishing water, soil, and energy resources resulting from increases in population numbers and wealth are putting pressure on agroecosystems to efficiently produce the most nutrient dense food while maintaining or enhancing natural resources. To address these ne...

  6. Matching consumer feeding behaviours and resource traits: a fourth-corner problem in food-web theory.

    PubMed

    Monteiro, Angelo Barbosa; Faria, Lucas Del Bianco

    2018-06-06

    For decades, food web theory has proposed phenomenological models for the underlying structure of ecological networks. Generally, these models rely on latent niche variables that match the feeding behaviour of consumers with their resource traits. In this paper, we used a comprehensive database to evaluate different hypotheses on the best dependency structure of trait-matching patterns between consumers and resource traits. We found that consumer feeding behaviours had complex interactions with resource traits; however, few dimensions (i.e. latent variables) could reproduce the trait-matching patterns. We discuss our findings in the light of three food web models designed to reproduce the multidimensionality of food web data; additionally, we discuss how using species traits clarify food webs beyond species pairwise interactions and enable studies to infer ecological generality at larger scales, despite potential taxonomic differences, variations in ecological conditions and differences in species abundance between communities. © 2018 John Wiley & Sons Ltd/CNRS.

  7. Natural Antioxidants in Foods and Medicinal Plants: Extraction, Assessment and Resources

    PubMed Central

    Xu, Dong-Ping; Li, Ya; Meng, Xiao; Zhou, Tong; Zhou, Yue; Zheng, Jie; Zhang, Jiao-Jiao; Li, Hua-Bin

    2017-01-01

    Natural antioxidants are widely distributed in food and medicinal plants. These natural antioxidants, especially polyphenols and carotenoids, exhibit a wide range of biological effects, including anti-inflammatory, anti-aging, anti-atherosclerosis and anticancer. The effective extraction and proper assessment of antioxidants from food and medicinal plants are crucial to explore the potential antioxidant sources and promote the application in functional foods, pharmaceuticals and food additives. The present paper provides comprehensive information on the green extraction technologies of natural antioxidants, assessment of antioxidant activity at chemical and cellular based levels and their main resources from food and medicinal plants. PMID:28067795

  8. Natural Antioxidants in Foods and Medicinal Plants: Extraction, Assessment and Resources.

    PubMed

    Xu, Dong-Ping; Li, Ya; Meng, Xiao; Zhou, Tong; Zhou, Yue; Zheng, Jie; Zhang, Jiao-Jiao; Li, Hua-Bin

    2017-01-05

    Natural antioxidants are widely distributed in food and medicinal plants. These natural antioxidants, especially polyphenols and carotenoids, exhibit a wide range of biological effects, including anti-inflammatory, anti-aging, anti-atherosclerosis and anticancer. The effective extraction and proper assessment of antioxidants from food and medicinal plants are crucial to explore the potential antioxidant sources and promote the application in functional foods, pharmaceuticals and food additives. The present paper provides comprehensive information on the green extraction technologies of natural antioxidants, assessment of antioxidant activity at chemical and cellular based levels and their main resources from food and medicinal plants.

  9. Factors determining the abundance and distribution of rodents in a shrub-steppe ecosystem: the role of shrubs.

    PubMed

    Parmenter, Robert R; MacMahon, James A

    1983-09-01

    This study addressed the relative importances of shrub "resources" on a rodent community in a sagebrush dominated shrub-steppe ecosystem in southwestern Wyoming. Direct effects of shrubs (i.e., providing rodents with "food and cover") were assessed by removing shrubs from a 1.25 ha study plot and monitoring both rodent populations and their food resources. Shrub architecture and shrub-related food resources were found to be unimportant to deermice (Peromyscus maniculatus), Great Basin pocket mice (Perognathus parvus) northern grasshopper mice (Onychomys leucogaster) and Uinta ground squirrels (Spermophilus armatus), as shrub removal caused no significant changes in population sizes, sex ratios or age structure. Least chipmunks (Eutamias minimus) responded to shrub removal by leaving the plot and moving into adjacent shrubland. The montane vole (Microtus montanus) population showed a slight increase following shrub removal. Shrub removal did not alter the abundance of major rodent food resources on the plot (percent cover of herbaceous vegetation, soil seed reserves and ground-dwelling arthropods). Micrometeorological data suggested that shrubs did not significantly ameliorate a nocturnal rodent's micro-climate, but may have affected diurnal rodents' thermal loading rates by removing shade. While shrub architecture and food resources do not directly affect most of the rodents in this shrub-steppe ecosystem, shrubs may be important to rodents in a long-term time frame. Shrubs provide "safe sites" for germination and growth of herbaceous vegetation, thereby enhancing the diversity of the potential rodent food resources.

  10. A case study of exploiting enterprise resource planning requirements

    NASA Astrophysics Data System (ADS)

    Niu, Nan; Jin, Mingzhou; Cheng, Jing-Ru C.

    2011-05-01

    The requirements engineering (RE) processes have become a key to conceptualising corporate-wide integrated solutions based on packaged enterprise resource planning (ERP) software. The RE literature has mainly focused on procuring the most suitable ERP package. Little is known about how an organisation exploits the chosen ERP RE model to frame the business application development. This article reports an exploratory case study of a key tenet of ERP RE adoption, namely that aligning business applications to the packaged RE model leads to integral practices and economic development. The case study analysed a series interrelated pilot projects developed for a business division of a large IT manufacturing and service company, using Oracle's appl1ication implementation method (AIM). The study indicated that AIM RE improved team collaboration and project management experience, but needed to make hidden assumptions explicit to support data visibility and integrity. Our study can direct researchers towards rigorous empirical evaluations of ERP RE adoption, collect experiences and lessons learned for practitioners, and help generate more effective and mature processes when exploiting ERP RE methods.

  11. Quantification of the Early Small-Scale Fishery in the North-Eastern Baltic Sea in the Late 17th Century

    PubMed Central

    Verliin, Aare; Ojaveer, Henn; Kaju, Katre; Tammiksaar, Erki

    2013-01-01

    Historical perspectives on fisheries and related human behaviour provide valuable information on fishery resources and their exploitation, helping to more appropriately set management targets and determine relevant reference levels. In this study we analyse historical fisheries and fish trade at the north-eastern Baltic Sea coast in the late 17th century. Local consumption and export together amounted to the annual removal of about 200 tonnes of fish from the nearby sea and freshwater bodies. The fishery was very diverse and exploited altogether one cyclostome and 17 fish species with over 90% of the catch being consumed locally. The exported fish consisted almost entirely of high-valued species with Stockholm (Sweden) being the most important export destination. Due to rich political history and natural features of the region, we suggest that the documented evidence of this small-scale fishery should be considered as the first quantitative summary of exploitation of aquatic living resources in the region and can provide a background for future analyses. PMID:23861914

  12. Exploitation of molecular profiling techniques for GM food safety assessment.

    PubMed

    Kuiper, Harry A; Kok, Esther J; Engel, Karl-Heinz

    2003-04-01

    Several strategies have been developed to identify unintended alterations in the composition of genetically modified (GM) food crops that may occur as a result of the genetic modification process. These include comparative chemical analysis of single compounds in GM food crops and their conventional non-GM counterparts, and profiling methods such as DNA/RNA microarray technologies, proteomics and metabolite profiling. The potential of profiling methods is obvious, but further exploration of specificity, sensitivity and validation is needed. Moreover, the successful application of profiling techniques to the safety evaluation of GM foods will require linked databases to be built that contain information on variations in profiles associated with differences in developmental stages and environmental conditions.

  13. News Release: USDA Joins Fair Food Network, State and Local Partners to

    Science.gov Websites

    Promote Nutrition Resources for Lead-Affected Flint Residents - PHE You may be trying to access Joins Fair Food Network, State and Local Partners to Promote Nutrition Resources for Lead-Affected Flint Residents News Release: USDA Joins Fair Food Network, State and Local Partners to Promote Nutrition

  14. Married Women's Resource Position and Household Food Expenditures in Cebu, Philippines

    ERIC Educational Resources Information Center

    Schmeer, Kammi K

    2005-01-01

    This study analyzes how married women use their access to and control over economic resources to increase household spending on food. Using data from Cebu, Philippines, where child malnutrition is high, this study finds that the more income women earn and control, the more households spend on food. Women's control over their income is particularly…

  15. Food First Resource Guide: Documentation on the Roots of World Hunger and Rural Poverty.

    ERIC Educational Resources Information Center

    Institute for Food and Development Policy, San Francisco, CA.

    This guide reviews resources used to develop the analysis of world hunger in "Food First: Beyond the Myth of Scarcity," Houghton Mifflin, 1977. The objectives are to help people understand the economic and political factors that contribute to food deprivation, document this analysis with credible sources, and inform high school, college, and…

  16. Electric energy production from food waste: Microbial fuel cells versus anaerobic digestion.

    PubMed

    Xin, Xiaodong; Ma, Yingqun; Liu, Yu

    2018-05-01

    A food waste resourceful process was developed by integrating the ultra-fast hydrolysis and microbial fuel cells (MFCs) for energy and resource recovery. Food waste was first ultra-fast hydrolyzed by fungal mash rich in hydrolytic enzymes in-situ produced from food waste. After which, the separated solids were readily converted to biofertilizer, while the liquid was fed to MFCs for direct electricity generation with a conversion efficiency of 0.245 kWh/kg food waste. It was estimated that about 192.5 million kWh of electricity could be produced from the food waste annually generated in Singapore, together with 74,390 tonnes of dry biofertilizer. Compared to anaerobic digestion, the proposed approach was more environmentally friendly and economically viable in terms of both electricity conversion and process cost. It is expected that this study may lead to the paradigm shift in food waste management towards ultra-fast concurrent recovery of resource and electricity with zero-solid discharge. Copyright © 2018 Elsevier Ltd. All rights reserved.

  17. Food security assessment in the coastal area of Demak Regency

    NASA Astrophysics Data System (ADS)

    Harini, R.; Handayani, H. N.; Ramdani, F. R.

    2018-04-01

    Food security is an issue of national and global level. Food is a basic human need to live. Without food will threaten human life. This research was conducted in coastal area of Demak Regency. This research is to understand the potential of human resources, natural resources and assess the level of food security of coastal communities. The data used are primary data through interviews with the local community. Also used Secondary data from government agencies. Data analysis used qualitative and quantitative descriptive methods through graphs, tables and maps. The results showed that potential of human resources in Demak coastal area (Wedung, Purworejo, and Sidogemah villages) is low. It can be indicated from education level of respondents in Demak are elementary school and junior high school. Beside, total households income are about 2-4 million. This study found that the households sampled are 90% is food insecured households. The most of households in Demak coastal area are about 90% households include on insecurity food category.

  18. Exploiting LCSH, LCC, and DDC To Retrieve Networked Resources: Issues and Challenges.

    ERIC Educational Resources Information Center

    Chan, Lois Mai

    This paper examines how the nature of the World Wide Web and characteristics of networked resources affect subject access and analyzes the requirements of effective indexing and retrieval tools. The current and potential uses of existing tools and possible courses of future development are explored in the context of recent research. The first…

  19. The forests of Michigan-from ice to axe to growth

    Treesearch

    Larry A. Leefers

    2010-01-01

    Michigan’s forests have evolved considerably during the past 4500 years. Post-glacial expansion of forests provided extensive, versatile resources for indigenous peoples. Eventually, these resources were exploited by immigrants to Michigan from Europe and the eastern US. Today, the forests are recovering and growing via natural regeneration and tree plantings, with...

  20. The opportunity cost of animal based diets exceeds all food losses.

    PubMed

    Shepon, Alon; Eshel, Gidon; Noor, Elad; Milo, Ron

    2018-04-10

    Food loss is widely recognized as undermining food security and environmental sustainability. However, consumption of resource-intensive food items instead of more efficient, equally nutritious alternatives can also be considered as an effective food loss. Here we define and quantify these opportunity food losses as the food loss associated with consuming resource-intensive animal-based items instead of plant-based alternatives which are nutritionally comparable, e.g., in terms of protein content. We consider replacements that minimize cropland use for each of the main US animal-based food categories. We find that although the characteristic conventional retail-to-consumer food losses are ≈30% for plant and animal products, the opportunity food losses of beef, pork, dairy, poultry, and eggs are 96%, 90%, 75%, 50%, and 40%, respectively. This arises because plant-based replacement diets can produce 20-fold and twofold more nutritionally similar food per cropland than beef and eggs, the most and least resource-intensive animal categories, respectively. Although conventional and opportunity food losses are both targets for improvement, the high opportunity food losses highlight the large potential savings beyond conventionally defined food losses. Concurrently replacing all animal-based items in the US diet with plant-based alternatives will add enough food to feed, in full, 350 million additional people, well above the expected benefits of eliminating all supply chain food waste. These results highlight the importance of dietary shifts to improving food availability and security. Copyright © 2018 the Author(s). Published by PNAS.

Top