WorldWideScience

Sample records for ecosystem ecology interactions

  1. Ecosystem management via interacting models of political and ecological processes

    Directory of Open Access Journals (Sweden)

    Haas, T. C.

    2004-01-01

    Full Text Available The decision to implement environmental protection options is a political one. Political realities may cause a country to not heed the most persuasive scientific analysis of an ecosystem's future health. A predictive understanding of the political processes that result in ecosystem management decisions may help guide ecosystem management policymaking. To this end, this article develops a stochastic, temporal model of how political processes influence and are influenced by ecosystem processes. This model is realized in a system of interacting influence diagrams that model the decision making of a country's political bodies. These decisions interact with a model of the ecosystem enclosed by the country. As an example, a model for Cheetah (Acinonyx jubatus management in Kenya is constructed and fitted to decision and ecological data.

  2. Pollutant threshold concentration determination in marine ecosystems using an ecological interaction endpoint

    International Nuclear Information System (INIS)

    Wang, Changyou; Liang, Shengkang; Guo, Wenting; Yu, Hua; Xing, Wenhui

    2015-01-01

    The threshold concentrations of pollutants are determined by extrapolating single-species effect data to community-level effects. This assumes the most sensitive endpoint of the life cycle of individuals and the species sensitivity distribution from single-species toxic effect tests, thus, ignoring the ecological interactions. The uncertainties due to this extrapolation can be partially overcome using the equilibrium point of a customized ecosystem. This method incorporates ecological interactions and integrates the effects on growth, survival, and ingestion into a single effect measure, the equilibrium point excursion in the customized ecosystem, in order to describe the toxic effects on plankton. A case study showed that the threshold concentration of copper calculated with the endpoint of the equilibrium point was 10 μg L −1 , which is significantly different from the threshold calculated with a single-species endpoint. The endpoint calculated using this method provides a more relevant measure of the ecological impact than any single individual-level endpoint. - Highlights: • Ecotoxicological effect of exposure to copper was tested on a customized ecosystem. • Equilibrium point of biomasses in the customized ecosystem was used as an endpoint. • Exposure–response relationship in a community level was built on equilibrium point. • A threshold concentration incorporating ecological interactions was derived. - The equilibrium biomass incorporating ecological interactions in a customized ecosystem was used as an endpoint to calculate the threshold concentration at a community level

  3. Parallel ecological networks in ecosystems

    NARCIS (Netherlands)

    Olff, Han; Alonso, David; Berg, Matty P.; Eriksson, B. Klemens; Loreau, Michel; Piersma, Theunis; Rooney, Neil

    2009-01-01

    In ecosystems, species interact with other species directly and through abiotic factors in multiple ways, often forming complex networks of various types of ecological interaction. Out of this suite of interactions, predator-prey interactions have received most attention. The resulting food webs,

  4. Parallel ecological networks in ecosystems

    Science.gov (United States)

    Olff, Han; Alonso, David; Berg, Matty P.; Eriksson, B. Klemens; Loreau, Michel; Piersma, Theunis; Rooney, Neil

    2009-01-01

    In ecosystems, species interact with other species directly and through abiotic factors in multiple ways, often forming complex networks of various types of ecological interaction. Out of this suite of interactions, predator–prey interactions have received most attention. The resulting food webs, however, will always operate simultaneously with networks based on other types of ecological interaction, such as through the activities of ecosystem engineers or mutualistic interactions. Little is known about how to classify, organize and quantify these other ecological networks and their mutual interplay. The aim of this paper is to provide new and testable ideas on how to understand and model ecosystems in which many different types of ecological interaction operate simultaneously. We approach this problem by first identifying six main types of interaction that operate within ecosystems, of which food web interactions are one. Then, we propose that food webs are structured among two main axes of organization: a vertical (classic) axis representing trophic position and a new horizontal ‘ecological stoichiometry’ axis representing decreasing palatability of plant parts and detritus for herbivores and detrivores and slower turnover times. The usefulness of these new ideas is then explored with three very different ecosystems as test cases: temperate intertidal mudflats; temperate short grass prairie; and tropical savannah. PMID:19451126

  5. Pollutant threshold concentration determination in marine ecosystems using an ecological interaction endpoint.

    Science.gov (United States)

    Wang, Changyou; Liang, Shengkang; Guo, Wenting; Yu, Hua; Xing, Wenhui

    2015-09-01

    The threshold concentrations of pollutants are determined by extrapolating single-species effect data to community-level effects. This assumes the most sensitive endpoint of the life cycle of individuals and the species sensitivity distribution from single-species toxic effect tests, thus, ignoring the ecological interactions. The uncertainties due to this extrapolation can be partially overcome using the equilibrium point of a customized ecosystem. This method incorporates ecological interactions and integrates the effects on growth, survival, and ingestion into a single effect measure, the equilibrium point excursion in the customized ecosystem, in order to describe the toxic effects on plankton. A case study showed that the threshold concentration of copper calculated with the endpoint of the equilibrium point was 10 μg L(-1), which is significantly different from the threshold calculated with a single-species endpoint. The endpoint calculated using this method provides a more relevant measure of the ecological impact than any single individual-level endpoint. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Analysis of Ecosystem Service Supply, Trade-Offs and Soical-Ecological Interactions in European Wood-Pastures

    DEFF Research Database (Denmark)

    Torralba Viorreta, Mario

    (Östergötland in Sweden, Southern Transylvania in Romania, Llanos de Trujillo in Spain and La Serena in Spain). The thesis provides an understanding of the dynamics and mechanisms interacting in the generation of ecosystem services in European wood-pastures, and the factors that govern this supply. The results...... show that wood-pastures offer a wide range of ecosystem services, which is due to, on the one hand, the high multifunctionality that characterizes them and, on the other hand, the multiple socio-cultural values they host. However, the specific interactions between the social and ecological components...

  7. Broadening the ecological context of ungulate-ecosystem interactions: the importance of space, seasonality, and nitrogen.

    Science.gov (United States)

    Murray, Bryan D; Webster, Christopher R; Bump, Joseph K

    2013-06-01

    Spatial heterogeneity of soil resources, particularly nitrogen availability, affects herbaceous-layer cover and diversity in temperate forest ecosystems. Current hypotheses predict that ungulate herbivores influence nitrogen availability at the stand scale, but how ungulates affect nitrogen availability at finer spatial scales that are relevant to the herb layer is less understood. We tested the hypothesis that ungulate exclusion reduces the spatial complexity of nitrogen availability at neighborhood scales (1-26 m) apart from mean stand scale effects. This outcome was expected due to a lack of ungulate nitrogenous waste deposition within exclosures and seasonally variable ungulate habitat use. To test this hypothesis we examined spatial patterning of ammonium and nitrate availability, herb-layer cover and diversity, and under-canopy solar radiation using geostatistical models. Our study sites included six stands of eastern hemlock (Tsuga canadensis) forest: three where white-tailed deer (Odocoileus virginianus) were excluded and three that were accessible to deer. Where deer were present, patch sizes of ammonium availability, cover, and diversity were smaller compared to deer exclosures, whereas mean site-level effects were not significant. Within deer exclosures cover and solar radiation were more similar in patch size than were cover and nitrogen availability. Our results suggest that browsing ungulates affect spatial patterns of herb-layer cover and diversity through the excretion of nitrogenous wastes in small, discrete patches. Ungulate-excreted nitrogen deposition and herbivory were concentrated in the dormant season, allowing herb-layer plants a greater opportunity to benefit from nitrogen additions. Therefore, the impact of ungulates on nitrogen cycling in forest ecosystems varies with spatial scale and the seasonal timing of ungulate impacts. In this way, ungulates may function as a seasonally dependent link between fine-scale and landscape

  8. Volcano ecology at Chaiten, Chile: geophysical processes interact with forest ecosystems

    Science.gov (United States)

    Swanson, F. J.; Crisafulli, C.; Jones, J. A.; Lara, A.

    2010-12-01

    The May 2008 eruption of Chaiten Volcano (Chile) offers many insights into volcano ecology -ecological responses to volcanic and associated hydrologic processes and ecosystem development in post-eruption landscapes. Varied intensities of pyroclastic density currents (PDC) and thickness of tephra fall deposits (to 50+ cm) created strong gradients of disturbance in several hundred square kilometers of native forest in a sector north to southeast from the volcano. A gradient from tree removal to toppled forest to standing, scorched forest extends 1.5 km northward from the caldera rim along the trajectory of a PDC. Close to the vent (e.g., 2 km NE from rim) a rain of ca. 10 cm of gravel tephra stripped foliage and twigs from tree canopies; farther away (23 km SE) 10 cm of fine tephra loaded the canopy, causing extensive fall of limbs >8 cm diameter. Even in the severely disturbed, north-flank PDC zone, surviving bamboo, ferns, and other herbs sprouted from pre-eruption soil and other refugia; sprouts of new foliage appeared on the boles and major limbs of several species of toppled and scorched, standing trees; animals including vertebrates (rodents and amphibians) and terrestrial invertebrates (e.g., insects and arachnids) either survived or quickly recolonized; and a diverse fungal community began decomposing the vast dead wood resource. During the second growing season we documented the presence of some plant species that had colonized by seed. Within two years after the eruption secondary ecological disturbances resulting from channel change and overbank deposition of fluvially transported tephra created new patches of damaged forest in riparian zones of streams draining the north flank and along the Rio Rayas and Rio Chaiten. These features parallel observations in the intensively-studied, post-1980-eruption landscape of Mount St. Helens over a similar time period. However, several aspects of ecological response to the two eruptions differ because of differences

  9. Ecological Values of Mangrove Forest Ecosystem

    OpenAIRE

    Kusmana, Cecep

    1996-01-01

    Research on quantification of ecological values of mangrove forest ecosystem are urgently needed, due to its importance as the basics for utilization and management of resources. From the ecological point of vlew, the main prohlem of mangrove ecosystem is rarity and inconsistency of data and limited accurate methods inquantifying ecological values of that ecosystem. Results show that mangrove has the significant ecological values on coastal ecosystem. However, there must be further research t...

  10. The Ecology and Evolution of Constructed Ecosystems as Green Infrastructure

    Directory of Open Access Journals (Sweden)

    Jeremy eLundholm

    2015-09-01

    Full Text Available Green infrastructure consists of ecosystems that provide valuable services to urban areas. Constructed ecosystems, including green roofs, bioretention systems, constructed wetlands and bioreactors are artificial, custom-built components of green infrastructure that are becoming more common in cities. Small size, strong spatial boundaries, ecological novelty and the role of human design characterize all constructed ecosystems, influencing their functions and interactions with other urban ecosystems. Here I outline the relevance of ecology and evolution in understanding the functioning of constructed ecosystems. In turn, a research focus on the distinctive aspects of constructed ecosystems can contribute to fundamental science.

  11. Towards a network ecology of software ecosystems

    DEFF Research Database (Denmark)

    Hansen, Klaus Marius; Manikas, Konstantinos

    2013-01-01

    of the "network ecology'' approach to the analysis of natural ecosystems. In doing so, we mine the Maven central Java repository and analyze two OSGi ecosystems: Apache Felix and Eclipse Equinox. In particular, we define the concept of an ecosystem ``neighborhood'', apply network ecology metrics...

  12. Integrative ecology: from molecules to ecosystems

    National Research Council Canada - National Science Library

    Woodward, G

    2010-01-01

    .... As such, none of these chapters are typical representatives of any single traditional field in ecology, as between them they attempt to forge new links from molecular biology to ecosystems ecology...

  13. Ecosystem services classification: A systems ecology perspective of the cascade framework

    CSIR Research Space (South Africa)

    La Notte, A

    2017-03-01

    Full Text Available and the environment. We present a refreshed conceptualization of ecosystem services which can support ecosystem service assessment techniques and measurement. We combine the notions of biomass, information and interaction from system ecology, with the ecosystem...

  14. Ecology in Small Aquatic Ecosystems

    DEFF Research Database (Denmark)

    Andersen, Mikkel René

    Small ecosystems are many-fold more abundant than their larger counterparts. Both on regional and global scale small lakes outnumber medium and large lakes and account for a much larger surface area. Small streams are also far more common than rivers. Despite their abundance small ecosystems are ...

  15. Reconnecting Social and Ecological Resilience in Salmon Ecosystems

    Directory of Open Access Journals (Sweden)

    Daniel L. Bottom

    2009-06-01

    Full Text Available Fishery management programs designed to control Pacific salmon (Oncorhynchus spp. for optimum production have failed to prevent widespread fish population decline and have caused greater uncertainty for salmon, their ecosystems, and the people who depend upon them. In this special feature introduction, we explore several key attributes of ecosystem resilience that have been overlooked by traditional salmon management approaches. The dynamics of salmon ecosystems involve social-ecological interactions across multiple scales that create difficult mismatches with the many jurisdictions that manage fisheries and other natural resources. Of particular importance to ecosystem resilience are large-scale shifts in oceanic and climatic regimes or in global economic conditions that unpredictably alter social and ecological systems. Past management actions that did not account for such changes have undermined salmon population resilience and increased the risk of irreversible regime shifts in salmon ecosystems. Because salmon convey important provisioning, cultural, and supporting services to their local watersheds, widespread population decline has undermined both human well-being and ecosystem resilience. Strengthening resilience will require expanding habitat opportunities for salmon populations to express their maximum life-history variation. Such actions also may benefit the "response diversity" of local communities by expanding the opportunities for people to express diverse social and economic values. Reestablishing social-ecological connections in salmon ecosystems will provide important ecosystem services, including those that depend on clean water, ample stream flows, functional wetlands and floodplains, intact riparian systems, and abundant fish populations.

  16. Chasing Ecological Interactions.

    Science.gov (United States)

    Jordano, Pedro

    2016-09-01

    Basic research on biodiversity has concentrated on individual species-naming new species, studying distribution patterns, and analyzing their evolutionary relationships. Yet biodiversity is more than a collection of individual species; it is the combination of biological entities and processes that support life on Earth. To understand biodiversity we must catalog it, but we must also assess the ways species interact with other species to provide functional support for the Tree of Life. Ecological interactions may be lost well before the species involved in those interactions go extinct; their ecological functions disappear even though they remain. Here, I address the challenges in studying the functional aspects of species interactions and how basic research is helping us address the fast-paced extinction of species due to human activities.

  17. Making research relevant? Ecological methods and the ecosystem services framework

    Science.gov (United States)

    Root-Bernstein, Meredith; Jaksic, Fabián. M.

    2017-07-01

    We examine some unexpected epistemological conflicts that arise at the interfaces between ecological science, the ecosystem services framework, policy, and industry. We use an example from our own research to motivate and illustrate our main arguments, while also reviewing standard approaches to ecological science using the ecosystem services framework. While we agree that the ecosystem services framework has benefits in its industrial applications because it may force economic decision makers to consider a broader range of costs and benefits than they would do otherwise, we find that many alignments of ecology with the ecosystem services framework are asking questions that are irrelevant to real-world applications, and generating data that does not serve real-world applications. We attempt to clarify why these problems arise and how to avoid them. We urge fellow ecologists to reflect on the kind of research that can lead to both scientific advances and applied relevance to society. In our view, traditional empirical approaches at landscape scales or with place-based emphases are necessary to provide applied knowledge for problem solving, which is needed once decision makers identify risks to ecosystem services. We conclude that the ecosystem services framework is a good policy tool when applied to decision-making contexts, but not a good theory either of social valuation or ecological interactions, and should not be treated as one.

  18. Ecological resilience indicators for mangrove ecosystems

    Science.gov (United States)

    Day, Richard H.; Allen, Scott T.; Brenner, Jorge; Goodin, Kathleen; Faber-Langendoen, Don; Ames, Katherine Wirt

    2018-01-01

    Mangrove ecosystems are coastal wetland ecosystems dominated by mangrove species that are typically found in the intertidal zone, characterized by frequently flooded saline soil conditions. The majority of the approximately 500,000 acres of mangrove ecosystem in the United States occurs in the NGoM, and almost all of that is in Florida, with over 90 percent in the four southern counties of Lee, Collier, Miami-Dade, and Monroe. Scattered stands and individuals occur north and westward into Louisiana and Texas (Osland et al., 2016). The three common mangrove species are: black mangrove (Avicennia germinans), white mangrove (Laguncularia racemosa), and red mangrove (Rhizophora mangle). The mangrove system described in this project includes Tidal Mangrove Shrubland and Tidal Mangrove Forest as classified in CMECS (FGDC, 2012). It is classified as Caribbean Fringe Mangrove (G004) in the USNVC (2016), with a variety of distinct associations, based on species dominance and ecological setting.

  19. Interaction webs in arctic ecosystems

    DEFF Research Database (Denmark)

    Schmidt, Niels Martin; Hardwick, Bess; Gilg, Olivier

    2017-01-01

    How species interact modulate their dynamics, their response to environmental change, and ultimately the functioning and stability of entire communities. Work conducted at Zackenberg, Northeast Greenland, has changed our view on how networks of arctic biotic interactions are structured, how they ...... that the combination of long-term, ecosystem-based monitoring, and targeted research projects offers the most fruitful basis for understanding and predicting the future of arctic ecosystems....

  20. Using ecological production functions to link ecological processes to ecosystem services.

    Science.gov (United States)

    Ecological production functions (EPFs) link ecosystems, stressors, and management actions to ecosystem services (ES) production. Although EPFs are acknowledged as being essential to improve environmental management, their use in ecological risk assessment has received relatively ...

  1. Interaction webs in arctic ecosystems

    DEFF Research Database (Denmark)

    Schmidt, Niels M.; Hardwick, Bess; Gilg, Olivier

    2017-01-01

    How species interact modulate their dynamics, their response to environmental change, and ultimately the functioning and stability of entire communities. Work conducted at Zackenberg, Northeast Greenland, has changed our view on how networks of arctic biotic interactions are structured, how...... they vary in time, and how they are changing with current environmental change: firstly, the high arctic interaction webs are much more complex than previously envisaged, and with a structure mainly dictated by its arthropod component. Secondly, the dynamics of species within these webs reflect changes...... that the combination of long-term, ecosystem-based monitoring, and targeted research projects offers the most fruitful basis for understanding and predicting the future of arctic ecosystems....

  2. Ecological restoration of southwestern ponderosa pine ecosystems: A broad perspective

    Science.gov (United States)

    Allen, Craig D.; Savage, Melissa; Falk, Donald A.; Suckling, Kieran F.; Swetnam, Thomas W.; Schulke, Todd; Stacey, Peter B.; Morgan, Penelope; Hoffman, Martos; Klingel, Jon T.

    2002-01-01

    The purpose of this paper is to promote a broad and flexible perspective on ecological restoration of Southwestern (U.S.) ponderosa pine forests. Ponderosa pine forests in the region have been radically altered by Euro-American land uses, including livestock grazing, fire suppression, and logging. Dense thickets of young trees now abound, old-growth and biodiversity have declined, and human and ecological communities are increasingly vulnerable to destructive crown fires. A consensus has emerged that it is urgent to restore more natural conditions to these forests. Efforts to restore Southwestern forests will require extensive projects employing varying combinations of young-tree thinning and reintroduction of low-intensity fires. Treatments must be flexible enough to recognize and accommodate: high levels of natural heterogeneity; dynamic ecosystems; wildlife and other biodiversity considerations; scientific uncertainty; and the challenges of on-the-ground implementation. Ecological restoration should reset ecosystem trends toward an envelope of “natural variability,” including the reestablishment of natural processes. Reconstructed historic reference conditions are best used as general guides rather than rigid restoration prescriptions. In the long term, the best way to align forest conditions to track ongoing climate changes is to restore fire, which naturally correlates with current climate. Some stands need substantial structural manipulation (thinning) before fire can safely be reintroduced. In other areas, such as large wilderness and roadless areas, fire alone may suffice as the main tool of ecological restoration, recreating the natural interaction of structure and process. Impatience, overreaction to crown fire risks, extractive economics, or hubris could lead to widespread application of highly intrusive treatments that may further damage forest ecosystems. Investments in research and monitoring of restoration treatments are essential to refine

  3. Ecology

    Science.gov (United States)

    Ternjej, Ivancica; Mihaljevic, Zlatko

    2017-10-01

    Ecology is a science that studies the mutual interactions between organisms and their environment. The fundamental subject of interest in ecology is the individual. Topics of interest to ecologists include the diversity, distribution and number of particular organisms, as well as cooperation and competition between organisms, both within and among ecosystems. Today, ecology is a multidisciplinary science. This is particularly true when the subject of interest is the ecosystem or biosphere, which requires the knowledge and input of biologists, chemists, physicists, geologists, geographists, climatologists, hydrologists and many other experts. Ecology is applied in a science of restoration, repairing disturbed sites through human intervention, in natural resource management, and in environmental impact assessments.

  4. Interactions between ecology and economics

    OpenAIRE

    Bittig, Bernhard

    1983-01-01

    Interactions between economics and ecology are analyzed by means of a deductive approach as well as by means of an iteration model. Additional approaches are briefly touched upon, with the Black box approach being considered as particularly suitable. Finally, the limits of all thought models are defined.

  5. Long-term, Ecosystem-Scale Changes in the Southern Benguela Marine Pelagic Social-Ecological System: Interaction of Natural and Human Drivers

    Directory of Open Access Journals (Sweden)

    Astrid Jarre

    2013-12-01

    Full Text Available South Africa's small pelagics fishery is currently the largest in volume and second largest in value in the southern Benguela. It exploits short-lived, small pelagic fishes such as anchovy (for reduction into fish meal and oil and sardine (for reduction as well as human consumption through canned products, and to a lesser extent redeye round herring and mesopelagics, largely for reduction. We explore the recent history (1940s to present of the social-ecological system around this fishery. The natural subsystem, at the scales of the ocean environment and the ecosystem, is characterized by high interannual and documented decadal-scale variability. We characterize the human social subsystem at the scales of the fishing industry, legislation, and west coast fishing towns, and demonstrate interdependencies between the natural and social subsystems by following system-scale changes. The pelagic fishing industry has evolved to deal with variability through consolidation, diversification, and range expansion. Legislation has increasingly looked for conservation of the resource while ensuring economic viability of the industry, and hence factory- and vessel-related jobs. Fishing communities under apartheid stayed largely dependent on company-generated infrastructure, combining seasonal employment in the fishing factories with inshore fishing, targeting rock lobster and line fish. While the pelagic industry persisted and communities survived, the resource base for both offshore and inshore fisheries gradually eroded. The advent of democracy in the mid-1990s brought allocation of long-term fishing rights to individuals or companies under conditions of depleted inshore resources aggravated by a shift in the distribution of pelagic fish away from the west coast towards the Cape south coast in the second half of the 1990s. The resultant loss of employment and fishing rights in the inshore has generated community coping strategies that include poaching and

  6. Bacterial - Fungal Interactions: ecology, mechanisms and challenges.

    Science.gov (United States)

    Deveau, A; Bonito, G; Uehling, J; Paoletti, M; Becker, M; Bindschedler, S; Hacquard, S; Hervé, V; Labbé, J; Lastovetsky, O A; Mieszkin, S; Millet, L J; Vajna, B; Junier, P; Bonfante, P; Krom, B P; Olsson, S; Elsas, J D van; Wick, L Y

    2018-02-19

    Fungi and bacteria are found living together in a wide variety of environments. Their interactions are significant drivers of many ecosystem functions and are important for the health of plants and animals. A large number of fungal and bacterial families are engaged in complex interactions that lead to critical behavioural shifts of the microorganisms ranging from mutualism to pathogenicity. The importance of bacterial-fungal interactions (BFI) in environmental science, medicine and biotechnology has led to the emergence of a dynamic and multidisciplinary research field that combines highly diverse approaches including molecular biology, genomics, geochemistry, chemical and microbial ecology, biophysics and ecological modelling. In this review, we discuss most recent advances that underscore the roles of BFI across relevant habitats and ecosystems. A particular focus is placed on the understanding of BFI within complex microbial communities and in regards of the metaorganism concept. We also discuss recent discoveries that clarify the (molecular) mechanisms involved in bacterial-fungal relationships, and the contribution of new technologies to decipher generic principles of BFI in terms of physical associations and molecular dialogues. Finally, we discuss future directions for researches in order to catalyse a synergy within the BFI research area and to resolve outstanding questions.

  7. Ecological risks of pesticides in freshwater ecosystems; Part 1: herbicides

    NARCIS (Netherlands)

    Brock, T.C.M.; Lahr, J.; Brink, van den P.J.

    2000-01-01

    A literature review of freshwater model ecosystem studies with herbicides was performed to assess the NOEC[sub]ecosystem for individual compounds, to compare these threshold levels with water quality standards, and to evaluate the ecological consequences of exceeding these standards. Studies were

  8. Bioassessment of the ecological integrity of river ecosystems using ...

    African Journals Online (AJOL)

    Bioassessment of the ecological integrity of river ecosystems using aquatic macroinvertebrates: an overview with a focus on South Africa. ... In conclusion, a number of potential avenues for further research regarding the use of macroinvertebrates in the bioassessment of river ecosystems are identified. Keywords: benthic ...

  9. Toward a social-ecological theory of forest macrosystems for improved ecosystem management

    Science.gov (United States)

    Kleindl, William J.; Stoy, Paul C.; Binford, Michael W.; Desai, Ankur R.; Dietze, Michael C.; Schultz, Courtney A.; Starr, Gregory; Staudhammer, Christina; Wood, David J. A.

    2018-01-01

    The implications of cumulative land-use decisions and shifting climate on forests, require us to integrate our understanding of ecosystems, markets, policy, and resource management into a social-ecological system. Humans play a central role in macrosystem dynamics, which complicates ecological theories that do not explicitly include human interactions. These dynamics also impact ecological services and related markets, which challenges economic theory. Here, we use two forest macroscale management initiatives to develop a theoretical understanding of how management interacts with ecological functions and services at these scales and how the multiple large-scale management goals work either in consort or conflict with other forest functions and services. We suggest that calling upon theories developed for organismal ecology, ecosystem ecology, and ecological economics adds to our understanding of social-ecological macrosystems. To initiate progress, we propose future research questions to add rigor to macrosystem-scale studies: (1) What are the ecosystem functions that operate at macroscales, their necessary structural components, and how do we observe them? (2) How do systems at one scale respond if altered at another scale? (3) How do we both effectively measure these components and interactions, and communicate that information in a meaningful manner for policy and management across different scales?

  10. Ecological interactions and the Netflix problem

    Directory of Open Access Journals (Sweden)

    Philippe Desjardins-Proulx

    2017-08-01

    Full Text Available Species interactions are a key component of ecosystems but we generally have an incomplete picture of who-eats-who in a given community. Different techniques have been devised to predict species interactions using theoretical models or abundances. Here, we explore the K nearest neighbour approach, with a special emphasis on recommendation, along with a supervised machine learning technique. Recommenders are algorithms developed for companies like Netflix to predict whether a customer will like a product given the preferences of similar customers. These machine learning techniques are well-suited to study binary ecological interactions since they focus on positive-only data. By removing a prey from a predator, we find that recommenders can guess the missing prey around 50% of the times on the first try, with up to 881 possibilities. Traits do not improve significantly the results for the K nearest neighbour, although a simple test with a supervised learning approach (random forests show we can predict interactions with high accuracy using only three traits per species. This result shows that binary interactions can be predicted without regard to the ecological community given only three variables: body mass and two variables for the species’ phylogeny. These techniques are complementary, as recommenders can predict interactions in the absence of traits, using only information about other species’ interactions, while supervised learning algorithms such as random forests base their predictions on traits only but do not exploit other species’ interactions. Further work should focus on developing custom similarity measures specialized for ecology to improve the KNN algorithms and using richer data to capture indirect relationships between species.

  11. Ecological interactions and the Netflix problem.

    Science.gov (United States)

    Desjardins-Proulx, Philippe; Laigle, Idaline; Poisot, Timothée; Gravel, Dominique

    2017-01-01

    Species interactions are a key component of ecosystems but we generally have an incomplete picture of who-eats-who in a given community. Different techniques have been devised to predict species interactions using theoretical models or abundances. Here, we explore the K nearest neighbour approach, with a special emphasis on recommendation, along with a supervised machine learning technique. Recommenders are algorithms developed for companies like Netflix to predict whether a customer will like a product given the preferences of similar customers. These machine learning techniques are well-suited to study binary ecological interactions since they focus on positive-only data. By removing a prey from a predator, we find that recommenders can guess the missing prey around 50% of the times on the first try, with up to 881 possibilities. Traits do not improve significantly the results for the K nearest neighbour, although a simple test with a supervised learning approach (random forests) show we can predict interactions with high accuracy using only three traits per species. This result shows that binary interactions can be predicted without regard to the ecological community given only three variables: body mass and two variables for the species' phylogeny. These techniques are complementary, as recommenders can predict interactions in the absence of traits, using only information about other species' interactions, while supervised learning algorithms such as random forests base their predictions on traits only but do not exploit other species' interactions. Further work should focus on developing custom similarity measures specialized for ecology to improve the KNN algorithms and using richer data to capture indirect relationships between species.

  12. Radioactive cesium in a boreal forest ecosystem. Ecological concepts in radioecology

    International Nuclear Information System (INIS)

    Palo, R.T.

    1991-01-01

    Radioecology is traditionally viewing ecosystems as process functional units while modern ecology focus more on interactions among populations and communities. Taken separately they may lead to incomplete conclusion about radionuclide behaviour and give a too simplified view of the system. I adopt an hierarchical approach by focusing on the forest ecosystem, populations and individuals. I present a theoretical framework commonly used in analysis of herbivore- plant interactions and give an example on how individual behaviour perturbate to higher levels of ecological organizations. (au) (20 refs.)

  13. Book Reviews Concepts of Ecosystem Ecology

    African Journals Online (AJOL)

    and emergent properties), and scientific method in ecology. ... this science: particularly the interface of habitat dynamics ... characteristic trophic structure and material cycles, six separate .... tion in using parts of it for extra readings in my senior.

  14. Nitrogen Deposition Effects on Ecosystem Services and Interactions with other Pollutants and Climate Change

    NARCIS (Netherlands)

    Erisman, J.W.; Leach, A.; Adams, M.; Vries, de W.

    2014-01-01

    Ecosystem services are defined as the ecological and socio-economic value of goods and services provided by natural and semi-natural ecosystems. Ecosystem services are being impacted by many human induced stresses, one of them being nitrogen (N) deposition and its interactions with other pollutants

  15. Examining Ecological and Ecosystem Level Impacts of Aquatic Invasive Species in Lake Michigan Using An Ecosystem Productivity Model, LM-Eco

    Science.gov (United States)

    Ecological and ecosystem-level impacts of aquatic invasive species in Lake Michigan were examined using the Lake Michigan Ecosystem Model (LM-Eco). The LM-Eco model includes a detailed description of trophic levels and their interactions within the lower food web of Lake Michiga...

  16. Ecosystem services as assessment endpoints for ecological risk assessment.

    Science.gov (United States)

    Munns, Wayne R; Rea, Anne W; Suter, Glenn W; Martin, Lawrence; Blake-Hedges, Lynne; Crk, Tanja; Davis, Christine; Ferreira, Gina; Jordan, Steve; Mahoney, Michele; Barron, Mace G

    2016-07-01

    Ecosystem services are defined as the outputs of ecological processes that contribute to human welfare or have the potential to do so in the future. Those outputs include food and drinking water, clean air and water, and pollinated crops. The need to protect the services provided by natural systems has been recognized previously, but ecosystem services have not been formally incorporated into ecological risk assessment practice in a general way in the United States. Endpoints used conventionally in ecological risk assessment, derived directly from the state of the ecosystem (e.g., biophysical structure and processes), and endpoints based on ecosystem services serve different purposes. Conventional endpoints are ecologically important and susceptible entities and attributes that are protected under US laws and regulations. Ecosystem service endpoints are a conceptual and analytical step beyond conventional endpoints and are intended to complement conventional endpoints by linking and extending endpoints to goods and services with more obvious benefit to humans. Conventional endpoints can be related to ecosystem services even when the latter are not considered explicitly during problem formulation. To advance the use of ecosystem service endpoints in ecological risk assessment, the US Environmental Protection Agency's Risk Assessment Forum has added generic endpoints based on ecosystem services (ES-GEAE) to the original 2003 set of generic ecological assessment endpoints (GEAEs). Like conventional GEAEs, ES-GEAEs are defined by an entity and an attribute. Also like conventional GEAEs, ES-GEAEs are broadly described and will need to be made specific when applied to individual assessments. Adoption of ecosystem services as a type of assessment endpoint is intended to improve the value of risk assessment to environmental decision making, linking ecological risk to human well-being, and providing an improved means of communicating those risks. Integr Environ Assess Manag

  17. The relationship between ecological restoration and the ecosystem services concept

    Directory of Open Access Journals (Sweden)

    Sasha Alexander

    2016-03-01

    Full Text Available Ecological restoration and the mainstreaming of the concept of ecosystem services will be critical if global society is to move toward sustainability. Conference of the Parties 21 (COP21 of the United Nations Framework Convention on Climate Change and COP12 of the Convention on Biological Diversity should help foster support for vastly increased investment in the better management and restoration of natural capital. Large-scale restoration demonstrably improves ecological functioning to sustain both biodiversity and human well-being. However, much progress is needed to improve the effectiveness and cost efficiency of any restoration. The ecosystem services concept provides a framework for identifying the types of restorative interventions needed to target different forms and degrees of degradation, and achieve goals related to both ecosystem health and delivery of services to people. Moreover, it can strengthen the argument for, and planning of, large-scale restoration and conservation of natural capital. We use case studies from four continents to help demonstrate how the interconnection between ecological restoration and the ecosystem services concept is being utilized in land-use planning and enlightened ecosystem management. We offer ways in which this relationship can be better understood and communicated to support the scaling up of restoration activities to the landscape and regional scales across the full spectrum of land uses and ecosystem types.

  18. The role of ecological models in linking ecological risk assessment to ecosystem services in agroecosystems

    NARCIS (Netherlands)

    Galic, N.G.; Schmolke, A.; Forbes, V.; Baveco, J.M.; Brink, van den P.J.

    2012-01-01

    Agricultural practices are essential for sustaining the human population, but at the same time they can directly disrupt ecosystem functioning. Ecological risk assessment (ERA) aims to estimate possible adverse effects of human activities on ecosystems and their parts. Current ERA practices,

  19. Nonlinear disruption of ecological interactions in response to nitrogen deposition.

    Science.gov (United States)

    Ochoa-Hueso, Raúl

    2016-10-01

    Global environmental change (GEC) is affecting species interactions and causing a rapid decline in biodiversity. In this study, I present a new Ecosystem Disruption Index to quantify the impacts of simulated nitrogen (N) deposition (0, 10, 20, and 50 kg N·ha -1 ·yr -1  + 6-7 kg N·ha -1 ·yr -1 background) on abiotic and biotic ecological interactions. This comparative index is based on pairwise linear and quadratic regression matrices. These matrices, calculated at the N treatment level, were constructed using a range of abiotic and biotic ecosystem constituents: soil pH, shrub cover, and the first component of several separate principal component analyses using soil fertility data (total carbon and N) and community data (annual plants, microorganisms, biocrusts, edaphic fauna) for a total of seven ecosystem constituents. Four years of N fertilization in a semiarid shrubland completely disrupted the network of ecological interactions, with a greater proportional increase in ecosystem disruption at low N addition levels. Biotic interactions, particularly those involving microbes, shrubs, and edaphic fauna, were more prone to be lost in response to N, whereas interactions involving soil properties were more resilient. In contrast, edaphic fauna was the only group directly affected by N addition, with mites and collembolans increasing their abundance with up to 20 kg N·ha -1 ·yr -1 and then decreasing, which supports the idea of higher-trophic-level organisms being more sensitive to disturbance due to more complex links with other ecosystem constituents. Future experimental studies evaluating the impacts of N deposition, and possibly other GEC drivers, on biodiversity and biotic and abiotic interactions may be able to explain results more effectively in the context of ecological networks as a key feature of ecosystem sensitivity. © 2016 by the Ecological Society of America.

  20. Interactions between temperature and nutrients across levels of ecological organization.

    Science.gov (United States)

    Cross, Wyatt F; Hood, James M; Benstead, Jonathan P; Huryn, Alexander D; Nelson, Daniel

    2015-03-01

    Temperature and nutrient availability play key roles in controlling the pathways and rates at which energy and materials move through ecosystems. These factors have also changed dramatically on Earth over the past century as human activities have intensified. Although significant effort has been devoted to understanding the role of temperature and nutrients in isolation, less is known about how these two factors interact to influence ecological processes. Recent advances in ecological stoichiometry and metabolic ecology provide a useful framework for making progress in this area, but conceptual synthesis and review are needed to help catalyze additional research. Here, we examine known and potential interactions between temperature and nutrients from a variety of physiological, community, and ecosystem perspectives. We first review patterns at the level of the individual, focusing on four traits--growth, respiration, body size, and elemental content--that should theoretically govern how temperature and nutrients interact to influence higher levels of biological organization. We next explore the interactive effects of temperature and nutrients on populations, communities, and food webs by synthesizing information related to community size spectra, biomass distributions, and elemental composition. We use metabolic theory to make predictions about how population-level secondary production should respond to interactions between temperature and resource supply, setting up qualitative predictions about the flows of energy and materials through metazoan food webs. Last, we examine how temperature-nutrient interactions influence processes at the whole-ecosystem level, focusing on apparent vs. intrinsic activation energies of ecosystem processes, how to represent temperature-nutrient interactions in ecosystem models, and patterns with respect to nutrient uptake and organic matter decomposition. We conclude that a better understanding of interactions between temperature and

  1. Ecological Diversity of Soil Fauna as Ecosystem Engineers in Small-Holder Cocoa Plantation in South Konawe

    Directory of Open Access Journals (Sweden)

    Laode Muhammad Harjoni Kilowasid

    2012-05-01

    Full Text Available Taxa diversity within soil fauna functional groups can affected ecosystem functioning such as ecosystem engineers,which influence decomposition and nutrient cycling. The objective of this study is to describe ecological diversityvariation within soil fauna as ecosystem engineers in soil ecosystem of cocoa (Theobroma cacao L. plantation.Sampling was conducted during one year period from five different ages of plantation. Soil fauna removed from soilcore using hand sorting methods. A total of 39 genera of soil fauna as ecosystem engineers were found during thesestudies. Thirty five genera belong to the group of Formicidae (ants, three genera of Isoptera (termites, and onegenera of Oligochaeta (earthworms. Ecological diversity variation within ecosystem engineers was detected withSimpson indices for dominance and evenness. The highest diversity of ecosystem engineers was in the young ageof plantation. This study reinforces the importance biotic interaction which contributed to the distribution andabundance within soil fauna community as ecosystem engineers in small-holder cocoa plantation.

  2. Ecological impacts of atmospheric pollution and interactions with climate change in terrestrial ecosystems of the Mediterranean Basin: Current research and future directions.

    Science.gov (United States)

    Ochoa-Hueso, Raúl; Munzi, Silvana; Alonso, Rocío; Arróniz-Crespo, María; Avila, Anna; Bermejo, Victoria; Bobbink, Roland; Branquinho, Cristina; Concostrina-Zubiri, Laura; Cruz, Cristina; Cruz de Carvalho, Ricardo; De Marco, Alessandra; Dias, Teresa; Elustondo, David; Elvira, Susana; Estébanez, Belén; Fusaro, Lina; Gerosa, Giacomo; Izquieta-Rojano, Sheila; Lo Cascio, Mauro; Marzuoli, Riccardo; Matos, Paula; Mereu, Simone; Merino, José; Morillas, Lourdes; Nunes, Alice; Paoletti, Elena; Paoli, Luca; Pinho, Pedro; Rogers, Isabel B; Santos, Arthur; Sicard, Pierre; Stevens, Carly J; Theobald, Mark R

    2017-08-01

    Mediterranean Basin ecosystems, their unique biodiversity, and the key services they provide are currently at risk due to air pollution and climate change, yet only a limited number of isolated and geographically-restricted studies have addressed this topic, often with contrasting results. Particularities of air pollution in this region include high O 3 levels due to high air temperatures and solar radiation, the stability of air masses, and dominance of dry over wet nitrogen deposition. Moreover, the unique abiotic and biotic factors (e.g., climate, vegetation type, relevance of Saharan dust inputs) modulating the response of Mediterranean ecosystems at various spatiotemporal scales make it difficult to understand, and thus predict, the consequences of human activities that cause air pollution in the Mediterranean Basin. Therefore, there is an urgent need to implement coordinated research and experimental platforms along with wider environmental monitoring networks in the region. In particular, a robust deposition monitoring network in conjunction with modelling estimates is crucial, possibly including a set of common biomonitors (ideally cryptogams, an important component of the Mediterranean vegetation), to help refine pollutant deposition maps. Additionally, increased attention must be paid to functional diversity measures in future air pollution and climate change studies to establish the necessary link between biodiversity and the provision of ecosystem services in Mediterranean ecosystems. Through a coordinated effort, the Mediterranean scientific community can fill the above-mentioned gaps and reach a greater understanding of the mechanisms underlying the combined effects of air pollution and climate change in the Mediterranean Basin. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Ecosystem services as assessment endpoints for ecological risk assessment

    Science.gov (United States)

    Ecosystem services (ES) are defined as the outputs of ecological processes that contribute to human welfare or have the potential to do so in the future, and include the production of food and drinking water, purification of air and water, pollination, and nutrient cycling. The n...

  4. Microbial ecology and nematode control in natural ecosystems

    NARCIS (Netherlands)

    Costa, S.R.; Van der Putten, W.H.; Kerry, B.R.

    2011-01-01

    Plant-parasitic nematodes have traditionally been studied in agricultural systems, where they can be pests of importance on a wide range of crops. Nevertheless, nematode ecology in natural ecosystems is receiving increasing interest because of the role of nematodes in soil food webs, nutrient

  5. Economics, socio-ecological resilience and ecosystem services

    NARCIS (Netherlands)

    Farley, J.; Voinov, A.

    2016-01-01

    The economic process transforms raw materials and energy into economic products and waste. On a finite planet, continued economic growth threatens to surpass critical socio-ecological thresholds and undermine ecosystem services upon which humans and all other species depend. For most systems,

  6. Attempts for an integrative (ecological) assessment of groundwater ecosystems status

    Science.gov (United States)

    Griebler, Christian; Kellermann, Claudia; Jürgen Hahn, Hans; Stein, Heide; Brielmann, Heike; Berkhoff, Sven; Fuchs, Andreas

    2014-05-01

    Today the assessment of the ecological status of surface waters is routine and made its way into national and international (e.g. European Water Framework Directive) regulations. For groundwater and aquifers a comparable approach, considering ecological aspects, is still missing. In contrast, groundwater monitoring and management schemes follow exclusively physical-chemical and quantitative criteria. However, groundwater systems are, although persistently neglected, ecosystems harboring diverse communities of microorganisms and invertebrates. Directly linked to the biological components, groundwater systems provide various ecosystem services of societal relevance (natural production of clean drinking water). In the recent past, we developed a first concept of an ecologically sound assessment scheme for groundwater systems. Work included (1) the selection of appropriate biological/ecological criteria, (2) set-up of a groundwater ecosystem typology, (3) deduction of natural biological groundwater background values and definition of reference conditions for selected sites, and (4) a first evaluation model. Groundwater has been analyzed repeatedly of more than 100 wells distributed over five investigation areas spread all over Germany. The investigated sites could be assigned to different natural regions, geological regions, hydrogeological units, and aquifer types. The mismatch of groundwater faunal communities with the established classification schemes led to the proposal of 'stygoregions' for Germany. The presentation introduces a number of microbial and faunistic assessment criteria, which have been tested and natural background values which have been deduced. Finally, a tiered framework for assessing groundwater ecosystem status which allows an easy and fast evaluation is introduced.

  7. Economic value of ecological information in ecosystem-based natural resource management depends on exploitation history.

    Science.gov (United States)

    Essington, Timothy E; Sanchirico, James N; Baskett, Marissa L

    2018-02-13

    Ecosystem approaches to natural resource management are seen as a way to provide better outcomes for ecosystems and for people, yet the nature and strength of interactions among ecosystem components is usually unknown. Here we characterize the economic benefits of ecological knowledge through a simple model of fisheries that target a predator (piscivore) and its prey. We solve for the management (harvest) trajectory that maximizes net present value (NPV) for different ecological interactions and initial conditions that represent different levels of exploitation history. Optimal management trajectories generally approached similar harvest levels, but the pathways toward those levels varied considerably by ecological scenario. Application of the wrong harvest trajectory, which would happen if one type of ecological interaction were assumed but in fact another were occurring, generally led to only modest reductions in NPV. However, the risks were not equal across fleets: risks of incurring large losses of NPV and missing management targets were much higher in the fishery targeting piscivores, especially when piscivores were heavily depleted. Our findings suggest that the ecosystem approach might provide the greatest benefits when used to identify system states where management performs poorly with imperfect knowledge of system linkages so that management strategies can be adopted to avoid those states. Copyright © 2018 the Author(s). Published by PNAS.

  8. Ecological impacts of atmospheric pollution and interactions with climate change in terrestrial ecosystems of the Mediterranean Basin: Current research and future directions

    International Nuclear Information System (INIS)

    Ochoa-Hueso, Raúl; Munzi, Silvana; Alonso, Rocío; Arróniz-Crespo, María; Avila, Anna; Bermejo, Victoria; Bobbink, Roland; Branquinho, Cristina; Concostrina-Zubiri, Laura; Cruz, Cristina; Cruz de Carvalho, Ricardo; De Marco, Alessandra; Dias, Teresa; Elustondo, David

    2017-01-01

    Mediterranean Basin ecosystems, their unique biodiversity, and the key services they provide are currently at risk due to air pollution and climate change, yet only a limited number of isolated and geographically-restricted studies have addressed this topic, often with contrasting results. Particularities of air pollution in this region include high O 3 levels due to high air temperatures and solar radiation, the stability of air masses, and dominance of dry over wet nitrogen deposition. Moreover, the unique abiotic and biotic factors (e.g., climate, vegetation type, relevance of Saharan dust inputs) modulating the response of Mediterranean ecosystems at various spatiotemporal scales make it difficult to understand, and thus predict, the consequences of human activities that cause air pollution in the Mediterranean Basin. Therefore, there is an urgent need to implement coordinated research and experimental platforms along with wider environmental monitoring networks in the region. In particular, a robust deposition monitoring network in conjunction with modelling estimates is crucial, possibly including a set of common biomonitors (ideally cryptogams, an important component of the Mediterranean vegetation), to help refine pollutant deposition maps. Additionally, increased attention must be paid to functional diversity measures in future air pollution and climate change studies to establish the necessary link between biodiversity and the provision of ecosystem services in Mediterranean ecosystems. Through a coordinated effort, the Mediterranean scientific community can fill the above-mentioned gaps and reach a greater understanding of the mechanisms underlying the combined effects of air pollution and climate change in the Mediterranean Basin. - Highlights: • Mediterranean Basin ecosystems are at risk due to air pollution and climate change. • A more robust monitoring network in conjunction with modelling estimates is crucial. • Monitoring networks should

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

    DEFF Research Database (Denmark)

    Bailey, Kevin M.; Ciannelli, Lorenzo; Hunsicker, Mary

    2010-01-01

    in marine ecosystems was held at the Oregon State University, Corvallis, OR, USA on 16–18 March 2010. The meeting brought together scientists from diverse fields of expertise including theoretical ecology, animal behaviour, fish and seabird ecology, statistics, fisheries science and ecosystem modelling......Climate and human influences on marine ecosystems are largely manifested by changes in predator–prey interactions. It follows that ecosystem-based management of the world's oceans requires a better understanding of food web relationships. An international workshop on predator–prey interactions...

  10. [Ecological regulation services of Hainan Island ecosystem and their valuation].

    Science.gov (United States)

    Ouyang, Zhiyun; Zhao, Tongqian; Zhao, Jingzhu; Xiao, Han; Wang, Xiaoke

    2004-08-01

    Ecosystem services imply the natural environmental conditions on which human life relies for existence, and their effectiveness formed and sustained by ecosystem and its ecological processes. In newly research reports, they were divided into four groups, i. e., provisioning services, regulation services, cultural services, and supporting services. To assess and valuate ecosystem services is the foundation of regional environmental reserve and development. Taking Hainan Island as an example and based on the structure and processes of natural ecosystem, this paper discussed the proper methods for regulation services assessment. The ecosystems were classified into 13 types including valley rain forest, mountainous rain forest, tropical monsoon forest, mountainous coppice forest, mountainous evergreen forest, tropical coniferous forest, shrubs, plantation, timber forest, windbreak forest, mangrove, savanna, and cropland, and then, the regulation services and their economic values of Hainan Island ecosystem were assessed and evaluated by terms of water-holding, soil conservancy, nutrient cycle, C fixation, and windbreak function. The economic value of the regulation services of Hainan Island ecosystem was estimated as 2035.88 x 10(8)-2153.39 x 10(8) RMB yuan, 8 times higher to its provisioning services (wood and agricultural products) which were estimated as only 254.06 x 10(8) RMB yuan. The result implied that ecosystem regulation services played an even more important role in the sustainable development of society and economy in Hainan Island.

  11. Complex trophic interactions in kelp forest ecosystems

    Science.gov (United States)

    Estes, J.A.; Danner, E.M.; Doak, D.F.; Konar, B.; Springer, A.M.; Steinberg, P.D.; Tinker, M. Tim; Williams, T.M.

    2004-01-01

    The distributions and abundances of species and populations change almost continuously. Understanding the processes responsible is perhaps ecology’s most fundamental challenge. Kelp-forest ecosystems in southwest Alaska have undergone several phase shifts between alga- and herbivore-dominated states in recent decades. Overhunting and recovery of sea otters caused the earlier shifts. Studies focusing on these changes demonstrate the importance of top-down forcing processes, a variety of indirect food-web interactions associated with the otter-urchin-kelp trophic cascade, and the role of food-chain length in the coevolution of defense and resistance in plants and their herbivores. This system unexpectedly shifted back to an herbivore-dominated state during the 1990s, because of a sea-otter population collapse that apparently was driven by increased predation by killer whales. Reasons for this change remain uncertain but seem to be linked to the whole-sale collapse of marine mammals in the North Pacific Ocean and southern Bering Sea. We hypothesize that killer whales sequentially "fished down" pinniped and sea-otter populations after their earlier prey, the great whales, were decimated by commercial whaling. The dynamics of kelp forests in southwest Alaska thus appears to have been influenced by an ecological chain reaction that encompassed numerous species and large scales of space and time.

  12. Interactions among ecosystem stressors and their importance in conservation

    Science.gov (United States)

    Darling, Emily S.; Brown, Christopher J.

    2016-01-01

    Interactions between multiple ecosystem stressors are expected to jeopardize biological processes, functions and biodiversity. The scientific community has declared stressor interactions—notably synergies—a key issue for conservation and management. Here, we review ecological literature over the past four decades to evaluate trends in the reporting of ecological interactions (synergies, antagonisms and additive effects) and highlight the implications and importance to conservation. Despite increasing popularity, and ever-finer terminologies, we find that synergies are (still) not the most prevalent type of interaction, and that conservation practitioners need to appreciate and manage for all interaction outcomes, including antagonistic and additive effects. However, it will not be possible to identify the effect of every interaction on every organism's physiology and every ecosystem function because the number of stressors, and their potential interactions, are growing rapidly. Predicting the type of interactions may be possible in the near-future, using meta-analyses, conservation-oriented experiments and adaptive monitoring. Pending a general framework for predicting interactions, conservation management should enact interventions that are robust to uncertainty in interaction type and that continue to bolster biological resilience in a stressful world. PMID:26865306

  13. Microbial ecology of mountain glacier ecosystems: biodiversity, ecological connections and implications of a warming climate.

    Science.gov (United States)

    Hotaling, Scott; Hood, Eran; Hamilton, Trinity L

    2017-08-01

    Glacier ecosystems are teeming with life on, beneath, and to a lesser degree, within their icy masses. This conclusion largely stems from polar research, with less attention paid to mountain glaciers that overlap environmentally and ecologically with their polar counterparts in some ways, but diverge in others. One difference lies in the susceptibility of mountain glaciers to the near-term threat of climate change, as they tend to be much smaller in both area and volume. Moreover, mountain glaciers are typically steeper, more dependent upon basal sliding for movement, and experience higher seasonal precipitation. Here, we provide a modern synthesis of the microbial ecology of mountain glacier ecosystems, and particularly those at low- to mid-latitudes. We focus on five ecological zones: the supraglacial surface, englacial interior, subglacial bedrock-ice interface, proglacial streams and glacier forefields. For each, we discuss the role of microbiota in biogeochemical cycling and outline ecological and hydrological connections among zones, underscoring the interconnected nature of these ecosystems. Collectively, we highlight the need to: better document the biodiversity and functional roles of mountain glacier microbiota; describe the ecological implications of rapid glacial retreat under climate change and resolve the relative contributions of ecological zones to broader ecosystem function. © 2017 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

  14. Ecological restoration, ecosystem services, and land use: a European perspective

    Directory of Open Access Journals (Sweden)

    Anne Tolvanen

    2016-12-01

    Full Text Available This special feature provides an overview on how the ecosystem service concept has been and can be incorporated into the science, practice, and policies of ecological restoration (ER and evidence-based land-use. It includes an edited selection of eleven invited and peer-reviewed papers based on presentations given during the 9th European Conference on Ecological Restoration in 2014. The focus is on Europe, but many contributors also make appraisals and recommendations at the global scale. Based on the contributors' papers, and our own overview of the promise of ecological restoration in the existing international treaties, coalitions, and conventions, we propose that the following actions could contribute to the positive impacts of ER on biodiversity maintenance, ecosystem functioning, progressive mainstreaming the concepts of both ER and ecosystem services, significant mitigation and offsetting of anthropogenic climate change, and lasting enhancement of both ecosystem and human health: •\tER should be incorporated into land use planning, wherever needed, and the synergies and trade-offs of different land use scenarios should be assessed in terms of their impacts on ecosystem services. •\tThe discourse of ER should be enlarged, wherever it is needed, to include multifunctional land use that simultaneously supports sustainable production systems, built environments, and the quality and quantity of diverse ecosystem services. This approach will generate ecological, social, and economic benefits in the long run. •\tMonitoring and evaluation of ER projects should be a continuous process involving careful selection of indicators chosen with the full range of stakeholders in mind, and a sufficiently long-term perspective to catch the progress of long-term or highly dynamic ecosystem processes. •\tScientists should actively participate in policy and land management discussions in order to give their views on the potential outcomes of decisions.

  15. Parasites, ecosystems and sustainability: an ecological and complex systems perspective.

    Science.gov (United States)

    Horwitz, Pierre; Wilcox, Bruce A

    2005-06-01

    Host-parasite relationships can be conceptualised either narrowly, where the parasite is metabolically dependent on the host, or more broadly, as suggested by an ecological-evolutionary and complex systems perspective. In this view Host-parasite relationships are part of a larger set of ecological and co-evolutionary interdependencies and a complex adaptive system. These interdependencies affect not just the hosts, vectors, parasites, the immediate agents, but also those indirectly or consequentially affected by the relationship. Host-parasite relationships also can be viewed as systems embedded within larger systems represented by ecological communities and ecosystems. So defined, it can be argued that Host-parasite relationships may often benefit their hosts and contribute significantly to the structuring of ecological communities. The broader, complex adaptive system view also contributes to understanding the phenomenon of disease emergence, the ecological and evolutionary mechanisms involved, and the role of parasitology in research and management of ecosystems in light of the apparently growing problem of emerging infectious diseases in wildlife and humans. An expanded set of principles for integrated parasite management is suggested by this perspective.

  16. Microbial ecology of fermentative hydrogen producing bioprocesses: useful insights for driving the ecosystem function.

    Science.gov (United States)

    Cabrol, Lea; Marone, Antonella; Tapia-Venegas, Estela; Steyer, Jean-Philippe; Ruiz-Filippi, Gonzalo; Trably, Eric

    2017-03-01

    One of the most important biotechnological challenges is to develop environment friendly technologies to produce new sources of energy. Microbial production of biohydrogen through dark fermentation, by conversion of residual biomass, is an attractive solution for short-term development of bioH2 producing processes. Efficient biohydrogen production relies on complex mixed communities working in tight interaction. Species composition and functional traits are of crucial importance to maintain the ecosystem service. The analysis of microbial community revealed a wide phylogenetic diversity that contributes in different-and still mostly unclear-ways to hydrogen production. Bridging this gap of knowledge between microbial ecology features and ecosystem functionality is essential to optimize the bioprocess and develop strategies toward a maximization of the efficiency and stability of substrate conversion. The aim of this review is to provide a comprehensive overview of the most up-to-date biodata available and discuss the main microbial community features of biohydrogen engineered ecosystems, with a special emphasis on the crucial role of interactions and the relationships between species composition and ecosystem service. The elucidation of intricate relationships between community structure and ecosystem function would make possible to drive ecosystems toward an improved functionality on the basis of microbial ecology principles. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  17. Terrestrial ecosystems: an ecological content for radionuclide research

    International Nuclear Information System (INIS)

    Heal, O.W.; Horrill, A.D.

    1983-01-01

    The distribution and retention of radionuclides within terrestrial ecosystems varies greatly with both the radionuclide and the environmental conditions. Physico-chemical conditions, particularly those of the soil, strongly influence element retention but superimposed and interacting with these conditions are the biological processes which control the dynamics of the labile fraction of most elements. Net ecosystem production expresses the complementary biological processes of primary production and decomposition which control the internal element dynamics and the balance of inputs to and outputs from terrestrial ecosystems. Analysis of ecosystem structure and function has shown that although research often concentrates on relatively stable stages of ecosystem development, element retention is high during the early stages of ecosystem succession through the accumulation of plant biomass and dead organic matter. Element output tends to increase with time reaching a balance with inputs in mature ecosystems. Following disturbance, plant uptake tends to be reduced and decomposition stimulated, resulting in increased output until secondary succession and accumulation is re-established. Research on element dynamics in ecosystems indicates that major factors influencing the mobility of radionuclides in terrestrial systems will be the successional state of the ecosystem and intensity of disturbance. (author)

  18. Approaches to modelling hydrology and ecosystem interactions

    Science.gov (United States)

    Silberstein, Richard P.

    2014-05-01

    As the pressures of industry, agriculture and mining on groundwater resources increase there is a burgeoning un-met need to be able to capture these multiple, direct and indirect stresses in a formal framework that will enable better assessment of impact scenarios. While there are many catchment hydrological models and there are some models that represent ecological states and change (e.g. FLAMES, Liedloff and Cook, 2007), these have not been linked in any deterministic or substantive way. Without such coupled eco-hydrological models quantitative assessments of impacts from water use intensification on water dependent ecosystems under changing climate are difficult, if not impossible. The concept would include facility for direct and indirect water related stresses that may develop around mining and well operations, climate stresses, such as rainfall and temperature, biological stresses, such as diseases and invasive species, and competition such as encroachment from other competing land uses. Indirect water impacts could be, for example, a change in groundwater conditions has an impact on stream flow regime, and hence aquatic ecosystems. This paper reviews previous work examining models combining ecology and hydrology with a view to developing a conceptual framework linking a biophysically defensable model that combines ecosystem function with hydrology. The objective is to develop a model capable of representing the cumulative impact of multiple stresses on water resources and associated ecosystem function.

  19. Trait- and density-mediated indirect interactions initiated by an exotic invasive plant autogenic ecosystem engineer

    Science.gov (United States)

    Dean E. Pearson

    2010-01-01

    Indirect interactions are important for structuring ecological systems. However, research on indirect effects has been heavily biased toward top-down trophic interactions, and less is known about other indirect-interaction pathways. As autogenic ecosystem engineers, plants can serve as initiators of nontrophic indirect interactions that, like top-down pathways, can...

  20. Ecosystem Services are Social-ecological Services in a Traditional Pastoral System: the Case of California's Mediterranean Rangelands

    Directory of Open Access Journals (Sweden)

    Lynn Huntsinger

    2014-03-01

    Full Text Available When attempting to value ecosystem services and support their production, two critical aspects may be neglected. The term "ecosystem services" implies that they are a function of natural processes; yet, human interaction with the environment may be key to the production of many. This can contribute to a misconception that ecosystem service production depends on, or is enhanced by, the coercion or removal of human industry. Second, in programs designed to encourage ecosystem service production and maintenance, too often the inter-relationship of such services with social and ecological processes and drivers at multiple scales is ignored. Thinking of such services as "social-ecological services" can reinforce the importance of human culture, perspectives, and economies to the production of ecosystem services. Using a social-ecological systems perspective, we explore the integral role of human activity and decisions at pasture, ranch, and landscape scales. Just as it does for understanding ecosystems, a hierarchical, multiscaled framework facilitates exploring the complexity of social-ecological systems as producers of ecosystem services, to develop approaches for the conservation of such services. Using California's Mediterranean rangelands as a study area, we suggest that using a multiscaled approach that considers the importance of the differing drivers and processes at each scale and the interactions among scales, and that incorporates social-ecological systems concepts, may help avoid mistakes caused by narrow assumptions about "natural" systems, and a lack of understanding of the need for integrated, multiscaled conservation programs.

  1. Integrating plant ecological responses to climate extremes from individual to ecosystem levels.

    Science.gov (United States)

    Felton, Andrew J; Smith, Melinda D

    2017-06-19

    Climate extremes will elicit responses from the individual to the ecosystem level. However, only recently have ecologists begun to synthetically assess responses to climate extremes across multiple levels of ecological organization. We review the literature to examine how plant responses vary and interact across levels of organization, focusing on how individual, population and community responses may inform ecosystem-level responses in herbaceous and forest plant communities. We report a high degree of variability at the individual level, and a consequential inconsistency in the translation of individual or population responses to directional changes in community- or ecosystem-level processes. The scaling of individual or population responses to community or ecosystem responses is often predicated upon the functional identity of the species in the community, in particular, the dominant species. Furthermore, the reported stability in plant community composition and functioning with respect to extremes is often driven by processes that operate at the community level, such as species niche partitioning and compensatory responses during or after the event. Future research efforts would benefit from assessing ecological responses across multiple levels of organization, as this will provide both a holistic and mechanistic understanding of ecosystem responses to increasing climatic variability.This article is part of the themed issue 'Behavioural, ecological and evolutionary responses to extreme climatic events'. © 2017 The Author(s).

  2. Predicting and detecting reciprocity between indirect ecological interactions and evolution.

    Science.gov (United States)

    Estes, James A; Brashares, Justin S; Power, Mary E

    2013-05-01

    Living nature can be thought of as a tapestry, defined not only by its constituent parts but also by how these parts are woven together. The weaving of this tapestry is a metaphor for species interactions, which can be divided into three broad classes: competitive, mutualistic, and consumptive. Direct interactions link together as more complex networks, for example, the joining of consumptive interactions into food webs. Food web dynamics are driven, in turn, by changes in the abundances of web members, whose numbers or biomass respond to bottom-up (resource limitation) and top-down (consumer limitation) forcing. The relative strengths of top-down and bottom-up forcing on the abundance of a given web member depend on its ecological context, including its topological position within the food web. Top-down effects by diverse consumers are nearly ubiquitous, in many cases influencing the structure and operation of ecosystems. While the ecological effects of such interactions are well known, far less is known of their evolutionary consequences. In this essay, we describe sundry consequences of these interaction chains on species and ecosystem processes, explain several known or suspected evolutionary effects of consumer-induced interaction chains, and identify areas where reciprocity between ecology and evolution involving the indirect effects of consumer-prey interaction chains might be further explored.

  3. Biological soil crusts (biocrusts) as a model system in community, landscape and ecosystem ecology

    Science.gov (United States)

    Bowker, Matthew A.; Maestre, Fernando T.; Eldridge, David; Belnap, Jayne; Castillo-Monroy, Andrea; Escolar, Cristina; Soliveres, Santiago

    2014-01-01

    Model systems have had a profound influence on the development of ecological theory and general principles. Compared to alternatives, the most effective models share some combination of the following characteristics: simpler, smaller, faster, general, idiosyncratic or manipulable. We argue that biological soil crusts (biocrusts) have unique combinations of these features that should be more widely exploited in community, landscape and ecosystem ecology. In community ecology, biocrusts are elucidating the importance of biodiversity and spatial pattern for maintaining ecosystem multifunctionality due to their manipulability in experiments. Due to idiosyncrasies in their modes of facilitation and competition, biocrusts have led to new models on the interplay between environmental stress and biotic interactions and on the maintenance of biodiversity by competitive processes. Biocrusts are perhaps one of the best examples of micro-landscapes—real landscapes that are small in size. Although they exhibit varying patch heterogeneity, aggregation, connectivity and fragmentation, like macro-landscapes, they are also compatible with well-replicated experiments (unlike macro-landscapes). In ecosystem ecology, a number of studies are imposing small-scale, low cost manipulations of global change or state factors in biocrust micro-landscapes. The versatility of biocrusts to inform such disparate lines of inquiry suggests that they are an especially useful model system that can enable researchers to see ecological principles more clearly and quickly.

  4. Communicative interactions involving plants: information, evolution, and ecology.

    Science.gov (United States)

    Mescher, Mark C; Pearse, Ian S

    2016-08-01

    The role of information obtained via sensory cues and signals in mediating the interactions of organisms with their biotic and abiotic environments has been a major focus of work on sensory and behavioral ecology. Information-mediated interactions also have important implications for broader ecological patterns emerging at the community and ecosystem levels that are only now beginning to be explored. Given the extent to which plants dominate the sensory landscapes of terrestrial ecosystems, information-mediated interactions involving plants should be a major focus of efforts to elucidate these broader patterns. Here we explore how such efforts might be enhanced by a clear understanding of information itself-a central and potentially unifying concept in biology that has nevertheless been the subject of considerable confusion-and of its relationship to adaptive evolution and ecology. We suggest that information-mediated interactions should be a key focus of efforts to more fully integrate evolutionary biology and ecology. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Integration of research infrastructures and ecosystem models toward development of predictive ecology

    Science.gov (United States)

    Luo, Y.; Huang, Y.; Jiang, J.; MA, S.; Saruta, V.; Liang, G.; Hanson, P. J.; Ricciuto, D. M.; Milcu, A.; Roy, J.

    2017-12-01

    The past two decades have witnessed rapid development in sensor technology. Built upon the sensor development, large research infrastructure facilities, such as National Ecological Observatory Network (NEON) and FLUXNET, have been established. Through networking different kinds of sensors and other data collections at many locations all over the world, those facilities generate large volumes of ecological data every day. The big data from those facilities offer an unprecedented opportunity for advancing our understanding of ecological processes, educating teachers and students, supporting decision-making, and testing ecological theory. The big data from the major research infrastructure facilities also provides foundation for developing predictive ecology. Indeed, the capability to predict future changes in our living environment and natural resources is critical to decision making in a world where the past is no longer a clear guide to the future. We are living in a period marked by rapid climate change, profound alteration of biogeochemical cycles, unsustainable depletion of natural resources, and deterioration of air and water quality. Projecting changes in future ecosystem services to the society becomes essential not only for science but also for policy making. We will use this panel format to outline major opportunities and challenges in integrating research infrastructure and ecosystem models toward developing predictive ecology. Meanwhile, we will also show results from an interactive model-experiment System - Ecological Platform for Assimilating Data into models (EcoPAD) - that have been implemented at the Spruce and Peatland Responses Under Climatic and Environmental change (SPRUCE) experiment in Northern Minnesota and Montpellier Ecotron, France. EcoPAD is developed by integrating web technology, eco-informatics, data assimilation techniques, and ecosystem modeling. EcoPAD is designed to streamline data transfer seamlessly from research infrastructure

  6. Linking microbial and ecosystem ecology using ecological stoichiometry: a synthesis of conceptual and empirical approaches

    Science.gov (United States)

    Hall, E.K.; Maixner, F.; Franklin, O.; Daims, H.; Richter, A.; Battin, T.

    2011-01-01

    Currently, one of the biggest challenges in microbial and ecosystem ecology is to develop conceptual models that organize the growing body of information on environmental microbiology into a clear mechanistic framework with a direct link to ecosystem processes. Doing so will enable development of testable hypotheses to better direct future research and increase understanding of key constraints on biogeochemical networks. Although the understanding of phenotypic and genotypic diversity of microorganisms in the environment is rapidly accumulating, how controls on microbial physiology ultimately affect biogeochemical fluxes remains poorly understood. We propose that insight into constraints on biogeochemical cycles can be achieved by a more rigorous evaluation of microbial community biomass composition within the context of ecological stoichiometry. Multiple recent studies have pointed to microbial biomass stoichiometry as an important determinant of when microorganisms retain or recycle mineral nutrients. We identify the relevant cellular components that most likely drive changes in microbial biomass stoichiometry by defining a conceptual model rooted in ecological stoichiometry. More importantly, we show how X-ray microanalysis (XRMA), nanoscale secondary ion mass spectroscopy (NanoSIMS), Raman microspectroscopy, and in situ hybridization techniques (for example, FISH) can be applied in concert to allow for direct empirical evaluation of the proposed conceptual framework. This approach links an important piece of the ecological literature, ecological stoichiometry, with the molecular front of the microbial revolution, in an attempt to provide new insight into how microbial physiology could constrain ecosystem processes.

  7. A tool for assessing ecological status of forest ecosystem

    Science.gov (United States)

    Rahman Kassim, Abd; Afizzul Misman, Muhammad; Azahari Faidi, Mohd; Omar, Hamdan

    2016-06-01

    Managers and policy makers are beginning to appreciate the value of ecological monitoring of artificially regenerated forest especially in urban areas. With the advent of more advance technology in precision forestry, high resolution remotely sensed data e.g. hyperspectral and LiDAR are becoming available for rapid and precise assessment of the forest condition. An assessment of ecological status of forest ecosystem was developed and tested using FRIM campus forest stand. The forest consisted of three major blocks; the old growth artificially regenerated native species forests, naturally regenerated forest and recent planted forest for commercial timber and other forest products. Our aim is to assess the ecological status and its proximity to the mature old growth artificially regenerated stand. We used airborne LiDAR, orthophoto and thirty field sampling quadrats of 20x20m for ground verification. The parameter assessments were grouped into four broad categories: a. forest community level-composition, structures, function; landscape structures-road network and forest edges. A metric of parameters and rating criteria was introduced as indicators of the forest ecological status. We applied multi-criteria assessment to categorize the ecological status of the forest stand. The paper demonstrates the application of the assessment approach using FRIM campus forest as its first case study. Its potential application to both artificially and naturally regenerated forest in the variety of Malaysian landscape is discussed

  8. Carbon-nitrogen interactions in forest ecosystems

    DEFF Research Database (Denmark)

    Gundersen, Per; Berg, Bjørn; Currie, W.S.

    This report is a summary of the main results from the EU project “Carbon – Nitrogen Interactions in Forest Ecosystems” (CNTER). Since carbon (C) and nitrogen (N) are bound together in organic matter we studied both the effect of N deposition on C cycling in forest ecosystems, and the effect of C ...

  9. Competition for vitamin B1 (thiamin) structures numerous ecological interactions.

    Science.gov (United States)

    Kraft, Clifford E; Angert, Esther R

    2017-06-01

    Thiamin (vitamin B1) is a cofactor required for essential biochemical reactions in all living organisms, yet free thiamin is scarce in the environment. The diversity of biochemical pathways involved in the acquisition, degradation, and synthesis of thiamin indicates that organisms have evolved numerous ecological strategies for meeting this nutritional requirement. In this review we synthesize information from multiple disciplines to show how the complex biochemistry of thiamin influences ecological outcomes of interactions between organisms in environments ranging from the open ocean and the Australian outback to the gastrointestinal tract of animals. We highlight population and ecosystem responses to the availability or absence of thiamin. These include widespread mortality of fishes, birds, and mammals, as well as the thiamin-dependent regulation of ocean productivity. Overall, we portray thiamin biochemistry as the foundation for molecularly mediated ecological interactions that influence survival and abundance of a vast array of organisms.

  10. Precipitation alters interactions in a grassland ecological community.

    Science.gov (United States)

    Deguines, Nicolas; Brashares, Justin S; Prugh, Laura R

    2017-03-01

    Climate change is transforming precipitation regimes world-wide. Changes in precipitation regimes are known to have powerful effects on plant productivity, but the consequences of these shifts for the dynamics of ecological communities are poorly understood. This knowledge gap hinders our ability to anticipate and mitigate the impacts of climate change on biodiversity. Precipitation may affect fauna through direct effects on physiology, behaviour or demography, through plant-mediated indirect effects, or by modifying interactions among species. In this paper, we examined the response of a semi-arid ecological community to a fivefold change in precipitation over 7 years. We examined the effects of precipitation on the dynamics of a grassland ecosystem in central California from 2007 to 2013. We conducted vegetation surveys, pitfall trapping of invertebrates, visual surveys of lizards and capture-mark-recapture surveys of rodents on 30 plots each year. We used structural equation modelling to evaluate the direct, indirect and modifying effects of precipitation on plants, ants, beetles, orthopterans, kangaroo rats, ground squirrels and lizards. We found pervasive effects of precipitation on the ecological community. Although precipitation increased plant biomass, direct effects on fauna were often stronger than plant-mediated effects. In addition, precipitation altered the sign or strength of consumer-resource and facilitative interactions among the faunal community such that negative or neutral interactions became positive or vice versa with increasing precipitation. These findings indicate that precipitation influences ecological communities in multiple ways beyond its recognized effects on primary productivity. Stochastic variation in precipitation may weaken the average strength of biotic interactions over time, thereby increasing ecosystem stability and resilience to climate change. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological

  11. Farming for Ecosystem Services: An Ecological Approach to Production Agriculture

    Science.gov (United States)

    Philip Robertson, G.; Gross, Katherine L.; Hamilton, Stephen K.; Landis, Douglas A.; Schmidt, Thomas M.; Snapp, Sieglinde S.; Swinton, Scott M.

    2014-01-01

    A balanced assessment of ecosystem services provided by agriculture requires a systems-level socioecological understanding of related management practices at local to landscape scales. The results from 25 years of observation and experimentation at the Kellogg Biological Station long-term ecological research site reveal services that could be provided by intensive row-crop ecosystems. In addition to high yields, farms could be readily managed to contribute clean water, biocontrol and other biodiversity benefits, climate stabilization, and long-term soil fertility, thereby helping meet society's need for agriculture that is economically and environmentally sustainable. Midwest farmers—especially those with large farms—appear willing to adopt practices that deliver these services in exchange for payments scaled to management complexity and farmstead benefit. Surveyed citizens appear willing to pay farmers for the delivery of specific services, such as cleaner lakes. A new farming for services paradigm in US agriculture seems feasible and could be environmentally significant. PMID:26955069

  12. Farming for Ecosystem Services: An Ecological Approach to Production Agriculture.

    Science.gov (United States)

    Philip Robertson, G; Gross, Katherine L; Hamilton, Stephen K; Landis, Douglas A; Schmidt, Thomas M; Snapp, Sieglinde S; Swinton, Scott M

    2014-05-01

    A balanced assessment of ecosystem services provided by agriculture requires a systems-level socioecological understanding of related management practices at local to landscape scales. The results from 25 years of observation and experimentation at the Kellogg Biological Station long-term ecological research site reveal services that could be provided by intensive row-crop ecosystems. In addition to high yields, farms could be readily managed to contribute clean water, biocontrol and other biodiversity benefits, climate stabilization, and long-term soil fertility, thereby helping meet society's need for agriculture that is economically and environmentally sustainable. Midwest farmers-especially those with large farms-appear willing to adopt practices that deliver these services in exchange for payments scaled to management complexity and farmstead benefit. Surveyed citizens appear willing to pay farmers for the delivery of specific services, such as cleaner lakes. A new farming for services paradigm in US agriculture seems feasible and could be environmentally significant.

  13. Ecological perspective: Linking ecology, GIS, and remote sensing to ecosystem management

    Science.gov (United States)

    Allen, Craig D.; Sample, V. Alaric

    1994-01-01

    Awareness of significant human impacts on the ecology of Earth's landscapes is not new (Thomas 1956). Over the past decade (Forman and Godron 1986, Urban et a1. 1987) applications of geographic information systems (GIS) and remote sensing technologies have supported a rapid rise in landscape.stale research. The heightened recognition within the research community of the ecological linkages between local sites and larger spatial scales has spawned increasing calls for more holistic management of landscapes (Noss 1983, Harris 1984, Risser 1985, Norse et al. 1986, Agee and Johnson 1988, Franklin 1989, Brooks and Grant 1992, Endangered Species Update-Special Issue 1993, Crow 1994, Grumbine 1994). As a result agencies such as the U.S. Forest Service, U.S. Fish and Wildlife Service, and National Park Service are now converging on "ecosystem management" as a new paradigm to sustainably manage wildlands and maintain biodiversity. However, as this transition occurs, several impediments to implementation of this new paradigm persist, including(1) significant uncenainty among many land managers about the definition and goals of ecosystem management,(2) inadequate ecological information on the past and present processes and structural conditions of target ecosystems,(3) insufficient experience on the part of land managers with the rapidly diversifying array of GIS and remote sensing tools to effectively use them to support ecology-based land management, and(4) a paucity of intimate, long-term relationships between people (including land managers) and the particular landscape communities to which they belong.This chapter provides an ecological perspective on these issues as applied to ecosystem management in a southwestern U.S. landscape.

  14. Ecosystem-atmosphere interactions in the Arctic

    DEFF Research Database (Denmark)

    López-Blanco, Efrén

    The terrestrial CO2 exchange in the Arctic plays an important role in the global carbon (C) cycle. The Arctic ecosystems, containing a large amount of organic carbon (C), are experiencing on-going warming in recent decades, which is affecting the C cycling and the feedback interactions between its...... of measurement sites, particularly covering full annual cycles, but also the frequent gaps in data affected by extreme conditions and remoteness. Combining ecosystem models and field observations we are able to study the underlying processes of Arctic CO2 exchange in changing environments. The overall aim...... of the research is to use data-model approaches to analyse the patterns of C exchange and their links to biological processes in Arctic ecosystems, studied in detail both from a measurement and a modelling perspective, but also from a local to a pan-arctic scale. In Paper I we found a compensatory response...

  15. Economics, socio-ecological resilience and ecosystem services.

    Science.gov (United States)

    Farley, Joshua; Voinov, Alexey

    2016-12-01

    The economic process transforms raw materials and energy into economic products and waste. On a finite planet, continued economic growth threatens to surpass critical socio-ecological thresholds and undermine ecosystem services upon which humans and all other species depend. For most systems, whether such thresholds exist, where they lie and whether they are reversible cannot be known with certainty until they are crossed. We argue that our central economic challenge is to maintain the resilience of the current socio-ecological regime. We must reduce net impacts of economic activity to avoid critical ecological thresholds while ensuring economic necessities. Conventional economists pursue continuous growth as the central goal of economic activity, and assume that the price mechanism and technological breakthroughs ensure system resilience. Unfortunately, the price mechanism fails to address ecological thresholds because it ignores unowned ecosystem services, and fails to address economic thresholds because it ignores the needs of the poorest individuals, who live on the edge of them. Panarchy theory suggests that systems go through a cycle of growth, conservation, release and renewal. Managing a subsystem too long for growth or conservation-which many consider to be the goal of sustainability-actually threatens to collapse the higher-level system upon which that subsystem depends. Black Swan theory suggests we should seek to reduce the risk of catastrophic thresholds and promote the likelihood of technological breakthroughs. Economic degrowth, or planned release, is required to avoid catastrophic collapse. At the same time, publicly funded, open source information can help stimulate the technological breakthroughs economists count on to ensure resilience. Copyright © 2016. Published by Elsevier Ltd.

  16. Algae-bacteria interactions: Evolution, ecology and emerging applications.

    Science.gov (United States)

    Ramanan, Rishiram; Kim, Byung-Hyuk; Cho, Dae-Hyun; Oh, Hee-Mock; Kim, Hee-Sik

    2016-01-01

    Algae and bacteria have coexisted ever since the early stages of evolution. This coevolution has revolutionized life on earth in many aspects. Algae and bacteria together influence ecosystems as varied as deep seas to lichens and represent all conceivable modes of interactions - from mutualism to parasitism. Several studies have shown that algae and bacteria synergistically affect each other's physiology and metabolism, a classic case being algae-roseobacter interaction. These interactions are ubiquitous and define the primary productivity in most ecosystems. In recent years, algae have received much attention for industrial exploitation but their interaction with bacteria is often considered a contamination during commercialization. A few recent studies have shown that bacteria not only enhance algal growth but also help in flocculation, both essential processes in algal biotechnology. Hence, there is a need to understand these interactions from an evolutionary and ecological standpoint, and integrate this understanding for industrial use. Here we reflect on the diversity of such relationships and their associated mechanisms, as well as the habitats that they mutually influence. This review also outlines the role of these interactions in key evolutionary events such as endosymbiosis, besides their ecological role in biogeochemical cycles. Finally, we focus on extending such studies on algal-bacterial interactions to various environmental and bio-technological applications. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  17. Bridging Food Webs, Ecosystem Metabolism, and Biogeochemistry Using Ecological Stoichiometry Theory

    Directory of Open Access Journals (Sweden)

    Nina Welti

    2017-07-01

    Full Text Available Although aquatic ecologists and biogeochemists are well aware of the crucial importance of ecosystem functions, i.e., how biota drive biogeochemical processes and vice-versa, linking these fields in conceptual models is still uncommon. Attempts to explain the variability in elemental cycling consequently miss an important biological component and thereby impede a comprehensive understanding of the underlying processes governing energy and matter flow and transformation. The fate of multiple chemical elements in ecosystems is strongly linked by biotic demand and uptake; thus, considering elemental stoichiometry is important for both biogeochemical and ecological research. Nonetheless, assessments of ecological stoichiometry (ES often focus on the elemental content of biota rather than taking a more holistic view by examining both elemental pools and fluxes (e.g., organismal stoichiometry and ecosystem process rates. ES theory holds the promise to be a unifying concept to link across hierarchical scales of patterns and processes in ecology, but this has not been fully achieved. Therefore, we propose connecting the expertise of aquatic ecologists and biogeochemists with ES theory as a common currency to connect food webs, ecosystem metabolism, and biogeochemistry, as they are inherently concatenated by the transfer of carbon, nitrogen, and phosphorous through biotic and abiotic nutrient transformation and fluxes. Several new studies exist that demonstrate the connections between food web ecology, biogeochemistry, and ecosystem metabolism. In addition to a general introduction into the topic, this paper presents examples of how these fields can be combined with a focus on ES. In this review, a series of concepts have guided the discussion: (1 changing biogeochemistry affects trophic interactions and ecosystem processes by altering the elemental ratios of key species and assemblages; (2 changing trophic dynamics influences the transformation and

  18. Evaluation of the ecological integrity and ecosystem health of three benthic networks influenced by coastal upwelling in the northern Chile

    Science.gov (United States)

    The ecological health of ecosystems relates to the maintenance or restoration of optimal system function when confronted with a disturbance. A healthy ecosystem is a prerequisite for ecological sustainability. Ecological integrity has been defined as an emergent property of ecosy...

  19. Transitions in Arctic ecosystems: Ecological implications of a changing hydrological regime

    Science.gov (United States)

    Wrona, Frederick J.; Johansson, Margareta; Culp, Joseph M.; Jenkins, Alan; Mârd, Johanna; Myers-Smith, Isla H.; Prowse, Terry D.; Vincent, Warwick F.; Wookey, Philip A.

    2016-03-01

    Numerous international scientific assessments and related articles have, during the last decade, described the observed and potential impacts of climate change as well as other related environmental stressors on Arctic ecosystems. There is increasing recognition that observed and projected changes in freshwater sources, fluxes, and storage will have profound implications for the physical, biogeochemical, biological, and ecological processes and properties of Arctic terrestrial and freshwater ecosystems. However, a significant level of uncertainty remains in relation to forecasting the impacts of an intensified hydrological regime and related cryospheric change on ecosystem structure and function. As the terrestrial and freshwater ecology component of the Arctic Freshwater Synthesis, we review these uncertainties and recommend enhanced coordinated circumpolar research and monitoring efforts to improve quantification and prediction of how an altered hydrological regime influences local, regional, and circumpolar-level responses in terrestrial and freshwater systems. Specifically, we evaluate (i) changes in ecosystem productivity; (ii) alterations in ecosystem-level biogeochemical cycling and chemical transport; (iii) altered landscapes, successional trajectories, and creation of new habitats; (iv) altered seasonality and phenological mismatches; and (v) gains or losses of species and associated trophic interactions. We emphasize the need for developing a process-based understanding of interecosystem interactions, along with improved predictive models. We recommend enhanced use of the catchment scale as an integrated unit of study, thereby more explicitly considering the physical, chemical, and ecological processes and fluxes across a full freshwater continuum in a geographic region and spatial range of hydroecological units (e.g., stream-pond-lake-river-near shore marine environments).

  20. Ecological processes in the cycling of radionuclides within arctic ecosystems

    International Nuclear Information System (INIS)

    Hanson, W.C.

    1986-01-01

    Worldwide fallout radionuclides in arctic ecosystems was investigated ecologically by circumpolar nations during 1959-80. Several of the radionuclides are isotopes of elements which currently contribute to arctic haze; they thus serve as effective tracers of biogeochemical processes. Investigations demonstrated the effective concentration of several radionuclides, particularly strontium-90 (an alkaline earth metal) and cesium-137 (a light alkali metal) which are chemical analogs of calcium and potassium, two very important stable elements in biotic systems. Transfer of 137 Cs through the lichen-cariboureindeer-man food chain characteristic of circumpolar nations, resulted in body burdens in Inuit that were 20 to 200 times greater than those in human populations of temperature latitudes. Radiation exposures from 90 Sr, 137 Cs and other natural and worldwide fallout radionuclides, were two to three times greater than for most other world populations. These results demonstrate the concentration capabilities of arctic ecosystems for several groups of chemical elements that have counterparts in arctic haze. These elements, therefore, provide the basis for considering the ecological implications of current situations

  1. A policy-driven large scale ecological restoration: quantifying ecosystem services changes in the Loess Plateau of China.

    Science.gov (United States)

    Lü, Yihe; Fu, Bojie; Feng, Xiaoming; Zeng, Yuan; Liu, Yu; Chang, Ruiying; Sun, Ge; Wu, Bingfang

    2012-01-01

    As one of the key tools for regulating human-ecosystem relations, environmental conservation policies can promote ecological rehabilitation across a variety of spatiotemporal scales. However, quantifying the ecological effects of such policies at the regional level is difficult. A case study was conducted at the regional level in the ecologically vulnerable region of the Loess Plateau, China, through the use of several methods including the Universal Soil Loss Equation (USLE), hydrological modeling and multivariate analysis. An assessment of the changes over the period of 2000-2008 in four key ecosystem services was undertaken to determine the effects of the Chinese government's ecological rehabilitation initiatives implemented in 1999. These ecosystem services included water regulation, soil conservation, carbon sequestration and grain production. Significant conversions of farmland to woodland and grassland were found to have resulted in enhanced soil conservation and carbon sequestration, but decreased regional water yield under a warming and drying climate trend. The total grain production increased in spite of a significant decline in farmland acreage. These trends have been attributed to the strong socioeconomic incentives embedded in the ecological rehabilitation policy. Although some positive policy results have been achieved over the last decade, large uncertainty remains regarding long-term policy effects on the sustainability of ecological rehabilitation performance and ecosystem service enhancement. To reduce such uncertainty, this study calls for an adaptive management approach to regional ecological rehabilitation policy to be adopted, with a focus on the dynamic interactions between people and their environments in a changing world.

  2. Multimodal Student Interaction Online: An Ecological Perspective

    Science.gov (United States)

    Berglund, Therese Ornberg

    2009-01-01

    This article describes the influence of tool and task design on student interaction in language learning at a distance. Interaction in a multimodal desktop video conferencing environment, FlashMeeting, is analyzed from an ecological perspective with two main foci: participation rates and conversational feedback strategies. The quantitative…

  3. West Nile virus ecology in a tropical ecosystem in Guatemala.

    Science.gov (United States)

    Morales-Betoulle, Maria E; Komar, Nicholas; Panella, Nicholas A; Alvarez, Danilo; López, María R; Betoulle, Jean-Luc; Sosa, Silvia M; Müller, María L; Kilpatrick, A Marm; Lanciotti, Robert S; Johnson, Barbara W; Powers, Ann M; Cordón-Rosales, Celia

    2013-01-01

    West Nile virus ecology has yet to be rigorously investigated in the Caribbean Basin. We identified a transmission focus in Puerto Barrios, Guatemala, and established systematic monitoring of avian abundance and infection, seroconversions in domestic poultry, and viral infections in mosquitoes. West Nile virus transmission was detected annually between May and October from 2005 to 2008. High temperature and low rainfall enhanced the probability of chicken seroconversions, which occurred in both urban and rural sites. West Nile virus was isolated from Culex quinquefasciatus and to a lesser extent, from Culex mollis/Culex inflictus, but not from the most abundant Culex mosquito, Culex nigripalpus. A calculation that combined avian abundance, seroprevalence, and vertebrate reservoir competence suggested that great-tailed grackle (Quiscalus mexicanus) is the major amplifying host in this ecosystem. West Nile virus transmission reached moderate levels in sentinel chickens during 2007, but less than that observed during outbreaks of human disease attributed to West Nile virus in the United States.

  4. Advances in animal ecology from 3D ecosystem mapping with LiDAR

    Science.gov (United States)

    Davies, A.; Asner, G. P.

    2015-12-01

    The advent and recent advances of Light Detection and Ranging (LiDAR) have enabled accurate measurement of 3D ecosystem structure. Although the use of LiDAR data is widespread in vegetation science, it has only recently (3D ecosystem structure for animals. We reviewed the studies to date that have used LiDAR in animal ecology, synthesising the insights gained. Structural heterogeneity is most conducive to increased animal richness and abundance, and increased complexity of vertical vegetation structure is more positively influential than traditionally measured canopy cover, which produces mixed results. However, different taxonomic groups interact with a variety of 3D canopy traits and some groups with 3D topography. LiDAR technology can be applied to animal ecology studies in a wide variety of environments to answer an impressive array of questions. Drawing on case studies from vastly different groups, termites and lions, we further demonstrate the applicability of LiDAR and highlight new understanding, ranging from habitat preference to predator-prey interactions, that would not have been possible from studies restricted to field based methods. We conclude with discussion of how future studies will benefit by using LiDAR to consider 3D habitat effects in a wider variety of ecosystems and with more taxa to develop a better understanding of animal dynamics.

  5. Ecological state of the Romanian Black Sea littoral lacustrine ecosystems

    Science.gov (United States)

    Gomoiu, M.-T.

    2009-04-01

    The author uses the results of his own researches as well as data from specialty literature to assess the ecological state of some typical lacustrine ecosystems considered, about 50 years ago, of major importance by their functions, services and researches, for the human populations in the settlements nearby. Based on this assessment the author recommends a few criteria which can be taken into account when programs of integrated management of these coastal ecosystems are initiated. The paper focuses on the study cases regarding the following major ecosystems: 1. Razelm-Sinoie Lagoon Complex - tightly linked to the Danube River and Delta systems, 2. Taşaul Lake - interfered in the last two decades by a branch of the DanubeRiver - Black Sea Canal and 3. Techirghiol Lake - for a long time under the sea level, a hyperhaline lake with therapeutic, sapropelic mud, disturbed by huge quantities of freshwaters infiltrated from the irrigation system. At present, the state of the lacustrine ecosystems at the Romanian Black Sea Coast can be characterized, mainly, by the following aspects: · Increase in the quantities of nutrients and chemical toxicants; · Rise in the level and frequency of eutrophication and pollution phenomena; · Drastic reduction of specific diversity; · Simplification of communities' structure - biocoenosis homogeneity; · Decrease in numerical abundance and biomass of benthic populations and consequently, low biofilter power by the decrease of the filter-feeder populations; · Worsening of the qualitative and the quantitative state of the biological benthic resources; · Thriving opportunistic forms (e.g. the worms causing sediment bioturbation); · Invasion by some exotic species, with harmful, unexpected consequences; · All populations undergo quantitative fluctuations; · Decrease in the fish population and in the use values of lacustrine assets, with strong impact on the welfare of the human society. Almost all pressure forms associated with the

  6. Ecological interactions drive evolutionary loss of traits.

    Science.gov (United States)

    Ellers, Jacintha; Kiers, E Toby; Currie, Cameron R; McDonald, Bradon R; Visser, Bertanne

    2012-10-01

    Loss of traits can dramatically alter the fate of species. Evidence is rapidly accumulating that the prevalence of trait loss is grossly underestimated. New findings demonstrate that traits can be lost without affecting the external phenotype, provided the lost function is compensated for by species interactions. This is important because trait loss can tighten the ecological relationship between partners, affecting the maintenance of species interactions. Here, we develop a new perspective on so-called `compensated trait loss' and how this type of trait loss may affect the evolutionary dynamics between interacting organisms. We argue that: (1) the frequency of compensated trait loss is currently underestimated because it can go unnoticed as long as ecological interactions are maintained; (2) by analysing known cases of trait loss, specific factors promoting compensated trait loss can be identified and (3) genomic sequencing is a key way forwards in detecting compensated trait loss. We present a comprehensive literature survey showing that compensated trait loss is taxonomically widespread, can involve essential traits, and often occurs as replicated evolutionary events. Despite its hidden nature, compensated trait loss is important in directing evolutionary dynamics of ecological relationships and has the potential to change facultative ecological interactions into obligatory ones. © 2012 Blackwell Publishing Ltd/CNRS.

  7. Ecosystem Services as a Boundary Concept: Arguments from Social Ecology

    Directory of Open Access Journals (Sweden)

    Christian Schleyer

    2017-06-01

    Full Text Available Ecosystem services (ES are defined as the interdependencies between society and nature. Despite several years of conceptual discussions, some challenges of the ES concept are far from being resolved. In particular, the usefulness of the concept for nature protection is questioned, and a strong critique is expressed concerning its contribution towards the neoliberal commodification of nature. This paper argues that these challenges can be addressed by dealing more carefully with ES as a boundary concept between different disciplines and between science and society. ES are neither about nature nor about human wellbeing, but about the mutual dependencies between nature and human wellbeing. These mutual interdependencies, however, create tensions and contradictions that manifest themselves in the boundary negotiations between different scientific disciplines and between science and society. This paper shows that approaches from Social Ecology can address these boundary negotiations and the power relations involved more explicitly. Finally, this implies the urgent need for more inter- and transdisciplinary collaboration in ES research. We conclude (1 that the social–ecological nature of ES must be elaborated more carefully while explicitly focussing on the interdependencies between nature and society; (2 to better implement inter- and transdisciplinary methods into ES research; and (3 that such ES research can—and to some extent already does—substantially enhance international research programmes such as Future Earth.

  8. Ecological effects of ionizing radiation on population and ecosystem: a computational model ecosystem study

    International Nuclear Information System (INIS)

    Doi, Masahiro; Fuma, Shoichi; Ishii, Nobuyuki; Sakashita, Tetsuya; Miyamoto, Kiriko; Takeda, Hiroshi; Kawabata, Zenichiro

    2003-01-01

    Ecosystem is a self-sustaining system of complexity, and their responses to the impacts are synergistic and subjected to the demographic stochasticity of the species, environmental stochasticity and randomness. Environmental fate and effects of radiation has ranged from observable DNA damage of the cell to the fare on tissues, individual, population, community and ecosystems. The quantitative, systematic individual-based model, SIM-COSM was developed to simulate impacts of radiation exposure and other toxicants on an aquatic microbial ecosystem (microcosm). The microcosm consists of heterotroph ciliate protozoa (Tetrahymena thermophila B) as a consumer, autotroph flagellate algae (Euglena gracilis Z) as a producer and saprotroph bacteria (Escherichia coli DH5) as a decomposer. The symbiosis among microbes is self-organized by realizing material cycle and sustained for more than 2 years after inoculation. The system can not afford to lose any one of the microbes to maintain its sustainability. Experimental ecotoxicological tests for (a) gamma radiation, (b) Manganese ions and (c) Gadolinium are summarized. Population dynamics of microbes in Microcosm and its computer simulations by SIM-COSM are shown together in a figure. Population dynamics in Microcosm and SIM-COSM exposed to 500 Gy of gamma-radiation at 50 days after inoculation are shown also in a figure. To take the effects on the interactions between species and environment into account, one option is to put the ecotoxicity tests as experimental micro ecosystem study and theoretical model ecosystem analysis. (M. Suetake)

  9. Social-ecological outcomes in recreational fisheries: the interaction of lakeshore development and stocking.

    Science.gov (United States)

    Ziegler, Jacob P; Golebie, Elizabeth J; Jones, Stuart E; Weidel, Brian C; Solomon, Christopher T

    2017-01-01

    Many ecosystems continue to experience rapid transformations due to processes like land use change and resource extraction. A systems approach to maintaining natural resources focuses on how interactions and feedbacks among components of complex social-ecological systems generate social and ecological outcomes. In recreational fisheries, residential shoreline development and fish stocking are two widespread human behaviors that influence fisheries, yet emergent social-ecological outcomes from these potentially interacting behaviors remain under explored. We applied a social-ecological systems framework using a simulation model and empirical data to determine whether lakeshore development is likely to promote stocking through its adverse effects on coarse woody habitat and thereby also on survival of juvenile and adult fish. We demonstrate that high lakeshore development is likely to generate dependency of the ecosystem on the social system, in the form of stocking. Further, lakeshore development can interact with social-ecological processes to create deficits for state-level governments, which threatens the ability to fund further ecosystem subsidies. Our results highlight the value of a social-ecological framework for maintaining ecosystem services like recreational fisheries. © 2016 by the Ecological Society of America.

  10. Preface: Biogeochemistry–ecosystem interaction on changing continental margins in the Anthropocene

    Digital Repository Service at National Institute of Oceanography (India)

    Liu, K-K.; Emeis, K.-C.; Levin, L.A.; Naqvi, S.W.A.; Roman, M.

    and hypercapnia in upwelling systems • Interactions between natural and social sciences for better steward- ship of continental margins. It has long been acknowledged (e.g., Doney, 2010; Liu et al., 2010) that marine ecosystems on continental margins, including... and possibly manage margin ecosystems in a changing world. Effective governance of social–ecological systems on continental margins is key to reducing the pervasive over- exploitation, depletion and destruction of marine resources and http://dx.doi.org/10...

  11. [Measuring water ecological carrying capacity with the ecosystem-service-based ecological footprint (ESEF) method: Theory, models and application].

    Science.gov (United States)

    Jiao, Wen-jun; Min, Qing-wen; Li, Wen-hua; Fuller, Anthony M

    2015-04-01

    Integrated watershed management based on aquatic ecosystems has been increasingly acknowledged. Such a change in the philosophy of water environment management requires recognizing the carrying capacity of aquatic ecosystems for human society from a more general perspective. The concept of the water ecological carrying capacity is therefore put forward, which considers both water resources and water environment, connects socio-economic development to aquatic ecosystems and provides strong support for integrated watershed management. In this paper, the authors proposed an ESEF-based measure of water ecological carrying capacity and constructed ESEF-based models of water ecological footprint and capacity, aiming to evaluate water ecological carrying capacity with footprint methods. A regional model of Taihu Lake Basin was constructed and applied to evaluate the water ecological carrying capacity in Changzhou City which located in the upper reaches of the basin. Results showed that human demand for water ecosystem services in this city had exceeded the supply capacity of local aquatic ecosystems and the significant gap between demand and supply had jeopardized the sustainability of local aquatic ecosystems. Considering aqua-product provision, water supply and pollutant absorption in an integrated way, the scale of population and economy aquatic ecosystems in Changzhou could bear only 54% of the current status.

  12. [Assessment on the changing conditions of ecosystems in key ecological function zones in China].

    Science.gov (United States)

    Huang, Lin; Cao, Wei; Wu, Dan; Gong, Guo-li; Zhao, Guo-song

    2015-09-01

    In this paper, the dynamics of ecosystem macrostructure, qualities and core services during 2000 and 2010 were analyzed for the key ecological function zones of China, which were classified into four types of water conservation, soil conservation, wind prevention and sand fixation, and biodiversity maintenance. In the water conservation ecological function zones, the areas of forest and grassland ecosystems were decreased whereas water bodies and wetland were increased in the past 11 years, and the water conservation volume of forest, grassland and wetland ecosystems increased by 2.9%. This region needs to reverse the decreasing trends of forest and grassland ecosystems. In the soil conservation ecological function zones, the area of farmland ecosystem was decreased, and the areas of forest, grassland, water bodies and wetland ecosystems were increased. The total amount of the soil erosion was reduced by 28.2%, however, the soil conservation amount of ecosystems increased by 38.1%. In the wind prevention and sand fixation ecological function zones, the areas of grassland, water bodies and wetland ecosystems were decreased, but forest and farmland ecosystems were increased. The unit amount of the soil. wind erosion was reduced and the sand fixation amount of ecosystems increased lightly. In this kind of region that is located in arid and semiarid areas, ecological conservation needs to reduce farmland area and give priority to the protection of the original ecological system. In the biodiversity maintenance ecological function zones, the areas of grassland and desert ecosystems were decreased and other types were increased. The human disturbances showed a weakly upward trend and needs to be reduced. The key ecological function zones should be aimed at the core services and the protecting objects, to assess quantitatively on the effectiveness of ecosystem conservation and improvement.

  13. Ecological Production Functions Linking Multiple Stressors to Ecosystem Services – A Case Study

    Science.gov (United States)

    The ecosystem services concept is being used to frame environmental protection goals that guide management of the risks of chemicals. Ecosystem services link changes in ecological systems to the benefits received by people. The use of ecosystem services in risk assessments and th...

  14. Global simulation of interactions between groundwater and terrestrial ecosystems

    Science.gov (United States)

    Braakhekke, M. C.; Rebel, K.; Dekker, S. C.; Smith, B.; Van Beek, L. P.; Sutanudjaja, E.; van Kampenhout, L.; Wassen, M. J.

    2016-12-01

    In many places in the world ecosystems are influenced by the presence of a shallow groundwater table. In these regions upward water flux due to capillary rise increases soil moisture availability in the root zone, which has strong positive effect on evapotranspiration. Additionally it has important consequences for vegetation dynamics and fluxes of carbon and nitrogen. Under water limited conditions shallow groundwater stimulates vegetation productivity, and soil organic matter decomposition while under saturated conditions groundwater may have a negative effect on these processes due to lack of oxygen. Furthermore, since plant species differ with respect to their root distribution, preference for moisture conditions, and resistance to oxygen stress, shallow groundwater also influences vegetation type. Finally, processes such as denitrification and methane production occur under strictly anaerobic conditions and are thus strongly influenced by moisture availability. Most global hydrological models and several land surface models simulate groundwater table dynamics and their effects on land surface processes. However, these models typically have relatively simplistic representation of vegetation and do not consider changes in vegetation type and structure and are therefore less suitable to represent effects of groundwater on biogeochemical fluxes. Dynamic global vegetation models (DGVMs), describe land surface from an ecological perspective, combining detailed description of vegetation dynamics and structure and biogeochemical processes. These models are thus more appropriate to simulate the ecological and biogeochemical effects of groundwater interactions. However, currently virtually all DGVMs ignore these effects, assuming that water tables are too deep to affect soil moisture in the root zone. We have implemented a tight coupling between the dynamic global ecosystem model LPJ-GUESS and the global hydrological model PCR-GLOBWB. Using this coupled model we aim to

  15. Beyond urban legends: an emerging framework of urban ecology, as illustrated by the Baltimore Ecosystem Study

    Science.gov (United States)

    Steward T.A. Pickett; Mary L. Cadenasso; J. Morgan Grove; Peter M. Groffman; Lawrence E. Band; Christopher G. Boone; William R., Jr. Burch; Susan B. Grimmond; John Hom; Jennifer C. Jenkins; Neely L. Law; Charles H. Nilon; Richard V. Pouyat; Katalin Szlavecz; Paige S. Warren; Matthew A. Wilson

    2008-01-01

    The emerging discipline of urban ecology is shifting focus from ecological processes embedded within cities to integrative studies of large urban areas as biophysical-social complexes. Yet this discipline lacks a theory. Results from the Baltimore Ecosystem Study, part of the Long Term Ecological Research Network, expose new assumptions and test existing assumptions...

  16. Social-ecological enabling conditions for payments for ecosystem services

    Directory of Open Access Journals (Sweden)

    Heidi R. Huber-Stearns

    2017-03-01

    Full Text Available The concept of "enabling conditions" centers on conditions that facilitate approaches to addressing social and ecological challenges. Although multiple fields have independently addressed the concept of enabling conditions, the literature lacks a shared understanding or integration of concepts. We propose a more synthesized understanding of enabling conditions beyond disciplinary boundaries by focusing on the enabling conditions that influence the implementation of a range of environmental policies termed payments for ecosystem services (PES. Through an analysis of key literature from different disciplinary perspectives, we examined how researchers and practitioners refer to and identify enabling conditions within the context of PES. Through our synthesis, we identified 24 distinct enabling conditions organized within 4 broad themes: biophysical, economic, governance, and social-cultural conditions. We found that the literature coalesces around certain enabling conditions, such as strong ecosystem science and existing institutions, regardless of disciplinary background or journal audience. We also observed key differences in how authors perceive the direction of influence for property type, program objectives, and number of actors. Additionally, we noted an emphasis on the importance of the contextual nature of many enabling conditions that may cause certain conditions to have a disproportionate impact on successful implementation in some circumstances. Unraveling the relative importance of specific enabling conditions in diverse contexts remains a research frontier. Ultimately, no single disciplinary perspective is likely to provide all necessary insights for PES creation, and given the intertwined nature of enabling conditions, practitioners need to consider insights from multiple dimensions. Our work suggests opportunities to better connect diverse conversations through integration of concepts, a common vocabulary, and a synthetic framework.

  17. Chemical ecology of insects and tritrophic interactions

    International Nuclear Information System (INIS)

    Ahmad, F.; Aslam, M.; Razaq, M.

    2004-01-01

    This paper reviews the chemical ecology of insects to explain the role of semiochemicals in plant-herbivore, herbivore-carnivore and plant-carnivore interactions. The semiochemical, mediating tritrophic interactions may be produced by plants, herbivores or their natural enemies (carnivores). Some semiochemicals attract the herbivores and carnivores and mediate interaction among them, while on the other hand some repel them. The semiochemicals are used by heribivores, parasites and predators as cues to locate food, host or prey. The same chemicals are also used for defensive purpose by some herbivores against their natural enemies as they are sequestered through their bodies. (author)

  18. Valuing Ecosystem Services in Terms of Ecological Risks and Returns

    DEFF Research Database (Denmark)

    Abson, Dave; Termansen, Mette

    2011-01-01

    Abstract: The economic valuation of ecosystem services is a key policy tool in stemming losses of biological diversity. It is proposed that the loss of ecosystem function and the biological resources within ecosystems is due in part to the failure of markets to recognize the benefits humans derive...... from ecosystems. Placing monetary values on ecosystem services is often suggested as a necessary step in correcting such market failures. We consider the effects of valuing different types of ecosystem services within an economic framework. We argue that provisioning and regulating ecosystem services...

  19. Introduction. Antarctic ecology: from genes to ecosystems. Part 2. Evolution, diversity and functional ecology.

    Science.gov (United States)

    Rogers, Alex D; Murphy, Eugene J; Johnston, Nadine M; Clarke, Andrew

    2007-12-29

    The Antarctic biota has evolved over the last 100 million years in increasingly isolated and cold conditions. As a result, Antarctic species, from micro-organisms to vertebrates, have adapted to life at extremely low temperatures, including changes in the genome, physiology and ecological traits such as life history. Coupled with cycles of glaciation that have promoted speciation in the Antarctic, this has led to a unique biota in terms of biogeography, patterns of species distribution and endemism. Specialization in the Antarctic biota has led to trade-offs in many ecologically important functions and Antarctic species may have a limited capacity to adapt to present climate change. These include the direct effects of changes in environmental parameters and indirect effects of increased competition and predation resulting from altered life histories of Antarctic species and the impacts of invasive species. Ultimately, climate change may alter the responses of Antarctic ecosystems to harvesting from humans. The unique adaptations of Antarctic species mean that they provide unique models of molecular evolution in natural populations. The simplicity of Antarctic communities, especially from terrestrial systems, makes them ideal to investigate the ecological implications of climate change, which are difficult to identify in more complex systems.

  20. Plant–insect interactions: the role of ecological stoichiometry

    Directory of Open Access Journals (Sweden)

    Michał Filipiak

    2017-03-01

    Full Text Available The energy budget of organisms is a primary factor used to generate hypotheses in ecosystem ecology and evolutionary theory. Therefore, previous studies have focused on the energy costs and benefits of adaptations, the efficiency of energy acquisition and investment, and energy budget limitations. The maintenance of stoichiometric balance is equally important because inconsistency between the chemical composition of the consumer’s tissues and that of its food sources strongly affects the major life-history traits of the consumer and may influence the consumer’s fitness and shape plant–herbivore interactions. In this short review, the framework of ecological stoichiometry is introduced, focusing on plant–insect interactions in terrestrial ecosystems. The use of the trophic stoichiometric ratio (TSR index is presented as a useful tool for indicating the chemical elements that are scarce in food and have the potential to limit the growth and development of herbivores, thereby influencing plant – herbivorous insect interactions. As an example, the elemental composition and stoichiometry of a pollen consumer (mason bee Osmia bicornis and its preferred pollen are compared. The growth and development of O. bicornis may be colimited by the scarcity of K, Na, and N in pollen, whereas the development of the cocoon might be colimited by the scarcity of P, Mg, K, Na, Zn, Ca, and N. A literature review of the elemental composition of pollen shows high taxonomical variability in the concentrations of bee-limiting elements. The optimized collection of pollen species based on the elemental composition may represent a strategy used by bees to overcome stoichiometric mismatches, influencing their interactions with plants. It is concluded that the dependence of life-history traits on food stoichiometry should be considered when discussing life history evolution and plant–herbivore interactions. The TSR index may serve as a convenient and powerful tool

  1. Social-ecological outcomes in recreational fisheries: The interaction of lakeshore development and stocking

    Science.gov (United States)

    Ziegler, Jacob P.; Golebie, Elizabeth J.; Jones, Stuart E.; Weidel, Brian C.; Solomon, Christopher T.

    2017-01-01

    Many ecosystems continue to experience rapid transformations due to processes like land use change and resource extraction. A systems approach to maintaining natural resources focuses on how interactions and feedbacks among components of complex social‐ecological systems generate social and ecological outcomes. In recreational fisheries, residential shoreline development and fish stocking are two widespread human behaviors that influence fisheries, yet emergent social‐ecological outcomes from these potentially interacting behaviors remain under explored. We applied a social‐ecological systems framework using a simulation model and empirical data to determine whether lakeshore development is likely to promote stocking through its adverse effects on coarse woody habitat and thereby also on survival of juvenile and adult fish. We demonstrate that high lakeshore development is likely to generate dependency of the ecosystem on the social system, in the form of stocking. Further, lakeshore development can interact with social‐ecological processes to create deficits for state‐level governments, which threatens the ability to fund further ecosystem subsidies. Our results highlight the value of a social‐ecological framework for maintaining ecosystem services like recreational fisheries.

  2. Spatially explicit assessment of ecosystem services in China's Loess Plateau: Patterns, interactions, drivers, and implications

    Science.gov (United States)

    Jiang, Chong; Zhang, Haiyan; Zhang, Zhidong

    2018-02-01

    Human demands for natural resources have significantly changed the natural landscape and induced ecological degradation and associated ecosystem services. An understanding of the patterns, interactions, and drivers of ecosystem services is essential for the ecosystem management and guiding targeted land use policy-making. The Losses Plateau (LP) provides ecosystem services including the carbon sequestration and soil retention, and exerts tremendous impacts on the midstream and downstream of the Yellow River. Three dominant ecosystem services between 2000 and 2012 within the LP were presented based on multiple source datasets and biophysical models. In addition, paired ecosystem services interactions were quantified using the correlation analysis and constraint line approach. The main conclusions are as follows. It was observed that the warming and wetting climate and ecological program jointly promoted the vegetation growth and carbon sequestration. The increasing precipitation throughout 2000-2012 was related to the soil retention and hydrological regulation fluctuations. The vegetation restoration played a positive role in the soil retention enhancement, thus substantially reduced water and sediment yields. The relationships between ecosystem services were not only correlations (tradeoffs or synergies), but rather constraint effects. The constraint effects between the three paired ecosystem services could be classified as the negative convex (carbon sequestration vs. hydrological regulation) and hump-shaped (soil retention vs. carbon sequestration and soil retention vs. hydrological regulation), and the coefficients of determination for the entire LP were 0.78, 0.84, and 0.65, respectively. In the LP, the rainfall (water availability) was the key constraint factor that affected the relationships between the paired ecosystem services. The spatially explicit mapping of ecosystem services and interaction analyses utilizing constraint line approach enriched the

  3. Linking the benefits of ecosystem services to sustainable spatial planning of ecological conservation strategies.

    Science.gov (United States)

    Huang, Lin; Cao, Wei; Xu, Xinliang; Fan, Jiangwen; Wang, Junbang

    2018-09-15

    The maintenance and improvement of ecosystem services on the Tibet Plateau are critical for national ecological security in China and are core objectives of ecological conservation in this region. In this paper, ecosystem service benefits of the Tibet Ecological Conservation Project were comprehensively assessed by estimating and mapping the spatiotemporal variation patterns of critical ecosystem services on the Tibet Plateau from 2000 to 2015. Furthermore, we linked the benefit assessment to the sustainable spatial planning of future ecological conservation strategies. Comparing the 8 years before and after the project, the water retention and carbon sink services of the forest, grassland and wetland ecosystems were slightly increased after the project, and the ecosystem sand fixation service has been steadily enhanced. The increasing forage supply service of grassland significantly reduced the grassland carrying pressure and eased the conflict between grassland and livestock. However, enhanced rainfall erosivity occurred due to increased rainfall, and root-layer soils could not recover in a short period of time, both factors have led to a decline in soil conservation service. The warm and humid climate is beneficial for the restoration of ecosystems on the Tibet Plateau, and the implementation of the Tibet Ecological Conservation Project has had a positive effect on the local improvement of ecosystem services. A new spatial planning strategy for ecological conservation was introduced and aims to establish a comprehensive, nationwide system to protect important natural ecosystems and wildlife, and to promote the sustainable use of natural resources. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Socio-ecological dynamics of Caribbean coral reef ecosystems and conservation opinion propagation.

    Science.gov (United States)

    Thampi, Vivek A; Anand, Madhur; Bauch, Chris T

    2018-02-07

    The Caribbean coral reef ecosystem has experienced a long history of deterioration due to various stressors. For instance, over-fishing of parrotfish - an important grazer of macroalgae that can prevent destructive overgrowth of macroalgae - has threatened reef ecosystems in recent decades and stimulated conservation efforts such as the formation of marine protected areas. Here we develop a mathematical model of coupled socio-ecological interactions between reef dynamics and conservation opinion dynamics to better understand how natural and human factors interact individually and in combination to determine coral reef cover. We find that the coupling opinion and reef systems generates complex dynamics that are difficult to anticipate without use of a model. For instance, instead of converging to a stable state of constant coral cover and conservationist opinion, the system can oscillate between low and high live coral cover as human opinion oscillates in a boom-bust cycle between complacency and concern. Out of various possible parameter manipulations, we also find that raising awareness of coral reef endangerment best avoids counter-productive nonlinear feedbacks and always increases and stabilizes live coral reef cover. In conclusion, an improved understanding of coupled opinion-reef dynamics under anthrogenic stressors is possible using coupled socio-ecological models, and such models should be further researched.

  5. Different types of interactions of links in artificial and natural ecosystems under anthropogenic pressure

    Science.gov (United States)

    Somova, Lydia; Pisman, Tamara; Mikheeva, Galina; Pechurkin, Nickolay

    The life of organisms in an ecosystem depends not only on abiotic factors, but also on the interaction of organisms in which they come with each other. The study of mechanisms of the bioregulation based on ecological - biochemical interactions of ecosystem links is necessary to know the ecosystem development, its stability, survival of ecosystem organisms. It is of high importance as for the creation of artificial ecosystems, and also for the study of natural ecosystems under anthropogenic pressure on them. To create well-functioning ecosystems is necessary to study and consider the basic types of relationships between organisms. The basic types of interactions between organisms have been studied with simple terrestrial and water ecosystems. 1. The interaction of microbiocenoses and plants were studied in experiments with agrocenoses. Microbiocenosis proposed for increase of productivity of plants and for obtaining ecologically pure production of plants has been created taking into account mutual relationships between species of microorganisms. 2. The experimental model of the atmosphere closed «autotroph - heterotroph» system in which heterotrophic link was the mixed population of yeasts (Candida utilis and Candida guilliermondii) was studied. The algae Chlorella vulgaris was used as an autotroph link. It was shown, that the competition result for heterotrophic link depended on strategy of populations of yeast in relation to a substrate and oxygen utilization. 3. As a result of experimental and theoretical modelling of a competition of algae Chlorella vulgaris and Scenedesmus quadricauda at continuous cultivation, the impossibility of their coexistence in the conditions of limitation on nitrogen was shown. 4. Pray-predator interactions between algae (Chlorella vulgaris, Scenedesmus quadricauda) and invertebrates (Paramecium caudatum, Brachionus plicatilis) were studied in experimental closed ecosystem. This work was partly supported by the Russian Foundation for

  6. Soil and water related forest ecosystem services and resilience of social ecological system in the Central Highlands of Ethiopia

    Science.gov (United States)

    Tekalign, Meron; Muys, Bart; Nyssen, Jan; Poesen, Jean

    2014-05-01

    In the central highlands of Ethiopia, deforestation and forest degradation are occurring and accelerating during the last century. The high population pressure is the most repeatedly mentioned reason. However, in the past 30 years researchers agreed that the absence of institutions, which could define the access rights to particular forest resources, is another underlying cause of forest depletion and loss. Changing forest areas into different land use types is affecting the biodiversity, which is manifested through not proper functioning of ecosystem services. Menagesha Suba forest, the focus of this study has been explored from various perspectives. However the social dimension and its interaction with the ecology have been addressed rarely. This research uses a combined theoretical framework of Ecosystem Services and that of Resilience thinking for understanding the complex social-ecological interactions in the forest and its influence on ecosystem services. For understanding the history and extent of land use land cover changes, in-depth literature review and a GIS and remote sensing analysis will be made. The effect of forest conversion into plantation and agricultural lands on soil and above ground carbon sequestration, fuel wood and timber products delivery will be analyzed with the accounting of the services on five land use types. The four ecosystem services to be considered are Supporting, Provisioning, Regulating, and Cultural services as set by the Millennium Ecosystem Assessment. A resilience based participatory framework approach will be used to analyze how the social and ecological systems responded towards the drivers of change that occurred in the past. The framework also will be applied to predict future uncertainties. Finally this study will focus on the possible interventions that could contribute to the sustainable management and conservation of the forest. An ecosystem services trade-off analysis and an environmental valuation of the water

  7. Ecological and resource economics as ecosystem management tools

    Science.gov (United States)

    Stephen Farber; Dennis. Bradley

    1999-01-01

    Economic pressures on ecosystems will only intensify in the future. Increased population levels, settlement patterns, and increased incomes will raise the demands for ecosystem resources and their services. The pressure to transform ecosystem natural assets into marketable commodities, whether by harvesting and mining resources or altering landscapes through...

  8. The estimation ecological risk for ground ecosystems in case of nuclear power plant failures

    International Nuclear Information System (INIS)

    Kremlenkov, D.Yu.; Kremlenkov, M.Yu.

    2004-01-01

    The results of probabilistic estimation of the damage for forest and agricultural ecosystems connected with cesium-137 and strontium-90 release during hypothetical accidents at NPPs are analyzed. The concept of radioecological risk including application of the models for radioactivity transport in atmosphere and calculation of of absorbed doses in ecosystem critical groups is used for the analysis. It is proved that the probable ecological damage expressed in terms of ecosystem destruction area depends on the scale of accidental radioisotope releases, meteorological conditions and radiation resistance of critical groups in plant associations. The conclusion is made that ecological risks expressed in the form of probable area of ecosystem destruction in the zone where dose loads lay in the range from minimal ecologically significant limit up to ecologically significant limit amount to 4-9% for conifers contaminated with cesium-137 and to 2-4% for agricultural crops contaminated with strontium-90 [ru

  9. Meeting the challenge of interacting threats in freshwater ecosystems: A call to scientists and managers

    Directory of Open Access Journals (Sweden)

    Laura S. Craig

    2017-12-01

    Full Text Available Human activities create threats that have consequences for freshwater ecosystems and, in most watersheds, observed ecological responses are the result of complex interactions among multiple threats and their associated ecological alterations. Here we discuss the value of considering multiple threats in research and management, offer suggestions for filling knowledge gaps, and provide guidance for addressing the urgent management challenges posed by multiple threats in freshwater ecosystems. There is a growing literature assessing responses to multiple alterations, and we build off this background to identify three areas that require greater attention: linking observed alterations to threats, understanding when and where threats overlap, and choosing metrics that best quantify the effects of multiple threats. Advancing science in these areas will help us understand existing ecosystem conditions and predict future risk from multiple threats. Because addressing the complex issues and novel ecosystems that arise from the interaction of multiple threats in freshwater ecosystems represents a significant management challenge, and the risks of management failure include loss of biodiversity, ecological goods, and ecosystem services, we also identify actions that could improve decision-making and management outcomes. These actions include drawing insights from management of individual threats, using threat attributes (e.g., causes and spatio-temporal dynamics to identify suitable management approaches, testing management strategies that are likely to be successful despite uncertainties about the nature of interactions among threats, avoiding unintended consequences, and maximizing conservation benefits. We also acknowledge the broadly applicable challenges of decision-making within a socio-political and economic framework, and suggest that multidisciplinary teams will be needed to innovate solutions to meet the current and future challenge of interacting

  10. Meeting the challenge of interacting threats in freshwater ecosystems: A call to scientists and managers

    Science.gov (United States)

    Craig, Laura S.; Olden, Julian D.; Arthington, Angela; Entrekin, Sally; Hawkins, Charles P.; Kelly, John J.; Kennedy, Theodore A.; Maitland, Bryan M.; Rosi, Emma J.; Roy, Allison; Strayer, David L.; Tank, Jennifer L.; West, Amie O.; Wooten, Matthew S.

    2017-01-01

    Human activities create threats that have consequences for freshwater ecosystems and, in most watersheds, observed ecological responses are the result of complex interactions among multiple threats and their associated ecological alterations. Here we discuss the value of considering multiple threats in research and management, offer suggestions for filling knowledge gaps, and provide guidance for addressing the urgent management challenges posed by multiple threats in freshwater ecosystems. There is a growing literature assessing responses to multiple alterations, and we build off this background to identify three areas that require greater attention: linking observed alterations to threats, understanding when and where threats overlap, and choosing metrics that best quantify the effects of multiple threats. Advancing science in these areas will help us understand existing ecosystem conditions and predict future risk from multiple threats. Because addressing the complex issues and novel ecosystems that arise from the interaction of multiple threats in freshwater ecosystems represents a significant management challenge, and the risks of management failure include loss of biodiversity, ecological goods, and ecosystem services, we also identify actions that could improve decision-making and management outcomes. These actions include drawing insights from management of individual threats, using threat attributes (e.g., causes and spatio-temporal dynamics) to identify suitable management approaches, testing management strategies that are likely to be successful despite uncertainties about the nature of interactions among threats, avoiding unintended consequences, and maximizing conservation benefits. We also acknowledge the broadly applicable challenges of decision-making within a socio-political and economic framework, and suggest that multidisciplinary teams will be needed to innovate solutions to meet the current and future challenge of interacting threats in

  11. Ecosystem development in roadside grasslands: Biotic control, plant-soil interactions, and dispersal limitations

    Science.gov (United States)

    Garcia-Palacios, P.; Bowker, M.A.; Maestre, F.T.; Soliveres, S.; Valladares, F.; Papadopoulos, J.; Escudero, A.

    2011-01-01

    Roadside grasslands undergoing secondary succession are abundant, and represent ecologically meaningful examples of novel, human-created ecosystems. Interactions between plant and soil communities (hereafter plant-soil interactions) are of major importance in understanding the role of biotic control in ecosystem functioning, but little is known about these links in the context of ecosystem restoration and succession. The assessment of the key biotic communities and interactions driving ecosystem development will help practitioners to better allocate the limited resources devoted to roadside grassland restoration. We surveyed roadside grasslands from three successional stages (0-2, 7-9, and > 20 years) in two Mediterranean regions of Spain. Structural equation modeling was used to evaluate how interactions between plants, biological soil crusts (BSCs), and soil microbial functional diversity (soil microorganisms) affect indicators of ecosystem development and restoration: plant similarity to the reference ecosystem, erosion control, and soil C storage and N accumulation. Changes in plant community composition along the successional gradient exerted the strongest influence on these indicators. High BSC cover was associated with high soil stability, and high soil microbial functional diversity from late-successional stages was associated with high soil fertility. Contrary to our expectations, the indirect effects of plants, mediated by either BSCs or soil microorganisms, were very weak in both regions, suggesting a minor role for plant-soil interactions upon ecosystem development indicators over long periods. Our results suggest that natural vegetation dynamics effectively improved ecosystem development within a time frame of 20 years in the grasslands evaluated. They also indicate that this time could be shortened if management actions focus on: (1) maintaining wellconserved natural areas close to roadsides to enhance plant compositional changes towards late

  12. [Calculation on ecological security baseline based on the ecosystem services value and the food security].

    Science.gov (United States)

    He, Ling; Jia, Qi-jian; Li, Chao; Xu, Hao

    2016-01-01

    The rapid development of coastal economy in Hebei Province caused rapid transition of coastal land use structure, which has threatened land ecological security. Therefore, calculating ecosystem service value of land use and exploring ecological security baseline can provide the basis for regional ecological protection and rehabilitation. Taking Huanghua, a city in the southeast of Hebei Province, as an example, this study explored the joint point, joint path and joint method between ecological security and food security, and then calculated the ecological security baseline of Huanghua City based on the ecosystem service value and the food safety standard. The results showed that ecosystem service value of per unit area from maximum to minimum were in this order: wetland, water, garden, cultivated land, meadow, other land, salt pans, saline and alkaline land, constructive land. The order of contribution rates of each ecological function value from high to low was nutrient recycling, water conservation, entertainment and culture, material production, biodiversity maintenance, gas regulation, climate regulation and environmental purification. The security baseline of grain production was 0.21 kg · m⁻², the security baseline of grain output value was 0.41 yuan · m⁻², the baseline of ecosystem service value was 21.58 yuan · m⁻², and the total of ecosystem service value in the research area was 4.244 billion yuan. In 2081 the ecological security will reach the bottom line and the ecological system, in which human is the subject, will be on the verge of collapse. According to the ecological security status, Huanghua can be divided into 4 zones, i.e., ecological core protection zone, ecological buffer zone, ecological restoration zone and human activity core zone.

  13. The roles of amensalistic and commensalistic interactions in large ecological network stability.

    Science.gov (United States)

    Mougi, Akihiko

    2016-07-13

    Ecological communities comprise diverse species and their interactions. Notably, ecological and evolutionary studies have revealed that reciprocal interactions such as predator-prey, competition, and mutualism, are key drivers of community dynamics. However, there is an argument that many species interactions are asymmetric, where one species unilaterally affects another species (amensalism or commensalism). This raises the unanswered question of what is the role of unilateral interactions in community dynamics. Here I use a theoretical approach to demonstrate that unilateral interactions greatly enhance community stability. The results suggested that amensalism and commensalism were more stabilizing than symmetrical interactions, such as competition and mutualism, but they were less stabilizing than an asymmetric antagonistic interaction. A mix of unilateral interactions increased stability. Furthermore, in communities with all interaction types, unilateral interactions tended to increase stability. This study suggests that unilateral interactions play a major role in maintaining communities, underlining the need to further investigate their roles in ecosystem dynamics.

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

    Directory of Open Access Journals (Sweden)

    Niels Jobstvogt

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

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

    Science.gov (United States)

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

    2014-01-01

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

  16. Spatial transferring of ecosystem services and property rights allocation of ecological compensation

    Science.gov (United States)

    Wen, Wujun; Xu, Geng; Wang, Xingjie

    2011-09-01

    Ecological compensation is an important means to maintain the sustainability and stability of ecosystem services. The property rights analysis of ecosystem services is indispensable when we implement ecological compensation. In this paper, ecosystem services are evaluated via spatial transferring and property rights analysis. Take the Millennium Ecosystem Assessment (MA) as an example, we attempt to classify the spatial structure of 31 categories of ecosystem services into four dimensions, i.e., local, regional, national and global ones, and divide the property rights structure into three types, i.e., private property rights, common property rights and state-owned property rights. Through the case study of forestry, farming industry, drainage area, development of mineral resources, nature reserves, functional areas, agricultural land expropriation, and international cooperation on ecological compensation, the feasible ecological compensation mechanism is illustrated under the spatial structure and property rights structure of the concerned ecosystem services. For private property rights, the ecological compensation mode mainly depends on the market mechanism. If the initial common property rights are "hidden," the implementation of ecological compensation mainly relies on the quota market transactions and the state investment under the state-owned property rights, and the fairness of property rights is thereby guaranteed through central administration.

  17. Antimicrobial discovery inspired by ecological interactions.

    Science.gov (United States)

    Molloy, Evelyn M; Hertweck, Christian

    2017-10-01

    Bacteria represent an unparalleled source of antibiotics used to treat infectious diseases. Yet, genome analyses have revealed that their full biosynthetic potential is much larger than expected. Valuable strategies to unearth hidden antibiotics are genome mining, pathway engineering and triggering, as well as co-cultivation approaches. Nevertheless, there is growing understanding that it is often essential to consider the ecological context and that there is a great potential for antimicrobial discovery from bacteria engaged in well-defined interactions with other organisms. Various ecological scenarios involving antimicrobial agents are outlined in this review: predator-prey and pathogenic interactions, the protection of insect assets such as offspring and cultivars, as well as host protection in symbiotic relationships with plants, invertebrates and animals/humans. The illustrative examples given reinforce the idea that examination of interactions between organisms can yield new antimicrobial compounds, and ultimately further our understanding of the function of these molecules in the environment. Copyright © 2017. Published by Elsevier Ltd.

  18. 'Ecological value added' in an integrated ecosystem-economy model. An indicator for sustainability

    International Nuclear Information System (INIS)

    Kratena, Kurt

    2004-01-01

    This paper sets up an input-output system of the relevant ecosystem flows that determine the carbon cycle in the global ecosystem. Introducing energy as the value added component in the ecosystem allows to calculate ecosystem prices expressed in 'energy values'. Linking the ecosystem with the economy in an integrated input-output model then allows to calculate prices of economic activities and of ecosystem activities. In analogy to the 'Ecological Footprint', where productive land is needed to absorb anthropogenic emissions, in this integrated input-output model additional carbon sinks are introduced for emission absorption. These carbon sinks need solar energy input, i.e. 'ecological value added'. Emission absorption as well as GDP therefore become activities valued in the numeraire of the integrated system, i.e.'energy values'. From that sustainability indicators can be derived

  19. Microbial interactions involving sulfur bacteria : implications for the ecology and evolution of bacterial communities

    NARCIS (Netherlands)

    Overmann, J; van Gemerden, H

    2000-01-01

    A major goal of microbial ecology is the identification and characterization of those microorganisms which govern transformations in natural ecosystems. This review summarizes our present knowledge of microbial interactions in the natural sulfur cycle. Central to the discussion is the recent

  20. Social-Ecological System in Seagrass Ecosystem Management at Kotania Bay Waters, Western Seram, Indonesia

    Science.gov (United States)

    Wawo, Mintje

    2017-10-01

    The concept of the Social-Ecological System (SES) of the coastal region, can be found in the seagrass ecosystem in the Kotania Bay Waters. Seagrass ecosystem as one of the productive ecosystem is part of an ecological system that can influence and influenced social system, in this case by people living around the seagrass ecosystem. This aim to estimating the socio-ecological vulnerability system of the seagrass ecosystem in the Kotania Bay Waters, the Linkage Matrix is used (de Chazal et al., 2008). This linkage matrix was created to determine the perception and understanding of the community on the ecosystem services provided by the seagrass ecosystem through the appraisal of various stakeholders. The results show that social values are rooted in the public perception of ecosystem goods and services, which are rarely considered. The ecological and economic value of natural resources is increasingly being used to determine the priority areas in the planning and management of coastal areas. The social value that exists in natural resources is highly recognized in conservation.

  1. Integral statistical eco-indices - effective complementary tool for assessment of ecological state of and ecological risks for water ecosystems

    International Nuclear Information System (INIS)

    Bashamkova, I

    2010-01-01

    Eco-indices are successfully used for assessment of the ecological state and risks of water reservoirs. They allow, already at early stages, to detect negative effects on water ecosystems caused by progressive anthropogenic impacts and widening of the spectrum of pollutants, and to quantitatively evaluate ecological risks and damage for water reservoirs. Implementing these modern tools to water quality assessment is one of the lines to make decisions concerning challenging environmental problems.

  2. Ecology and functional roles of biological soil crusts in semi-arid ecosystems of Spain

    Science.gov (United States)

    Maestre, Fernando T.; Bowker, Matthew A.; Cantón, Yolanda; Castillo-Monroy, Andrea P.; Cortina, Jordi; Escolar, Cristina; Escudero, Adrián; Lázaro, Roberto; Martínez, Isabel

    2015-01-01

    Biological soil crusts (BSCs), composed of lichens, cyanobacteria, mosses, liverworts and microorganisms, are key biotic components of arid and semi-arid ecosystems worldwide. Despite they are widespread in Spain, these organisms have been historically understudied in this country. This trend is beginning to change as a recent wave of research has been identifying BSCs as a model ecological system. Many studies and research projects carried out in Spain have explored the role of BSCs on water, carbon and nitrogen fluxes, the interactions between BSCs and vascular plants, their dynamics after disturbances, and their response to global change, among other topics. In this article we review the growing body of research on BSCs available from semi-arid areas of Spain, highlighting its importance for increasing our knowledge on this group of organisms. We also discuss how it is breaking new ground in emerging research areas on the ecology of BSCs, and how it can be use to guide management and restoration efforts. Finally, we provide directions for future research on the ecology of BSCs in Spain and abroad. PMID:25908884

  3. Mapping ecosystem types by means of ecological species groups

    NARCIS (Netherlands)

    Witte, J.P.M.; Meijden, van der R.

    2000-01-01

    A method is presented to deduce nation-wide maps of ecosystem types from FLORBASE. This national database contains data, per km2, on the presence of indigenous plant species that grow in the wild. The ecosystem types on the maps are defined on the basis of abiotic factors that determine the plant

  4. An automated platform for phytoplankton ecology and aquatic ecosystem monitoring

    NARCIS (Netherlands)

    Pomati, F.; Jokela, J.; Simona, M.; Veronesi, M.; Ibelings, B.W.

    2011-01-01

    High quality monitoring data are vital for tracking and understanding the causes of ecosystem change. We present a potentially powerful approach for phytoplankton and aquatic ecosystem monitoring, based on integration of scanning flow-cytometry for the characterization and counting of algal cells

  5. Ecological and Social Dynamics in Simple Models of Ecosystem Management

    Directory of Open Access Journals (Sweden)

    Stephen R. Carpenter

    1999-12-01

    Full Text Available Simulation models were developed to explore and illustrate dynamics of socioecological systems. The ecosystem is a lake subject to phosphorus pollution. Phosphorus flows from agriculture to upland soils, to surface waters, where it cycles between water and sediments. The ecosystem is multistable, and moves among domains of attraction depending on the history of pollutant inputs. The alternative states yield different economic benefits. Agents form expectations about ecosystem dynamics, markets, and/or the actions of managers, and choose levels of pollutant inputs accordingly. Agents have heterogeneous beliefs and/or access to information. Their aggregate behavior determines the total rate of pollutant input. As the ecosystem changes, agents update their beliefs and expectations about the world they co-create, and modify their actions accordingly. For a wide range of scenarios, we observe irregular oscillations among ecosystem states and patterns of agent behavior. These oscillations resemble some features of the adaptive cycle of panarchy theory.

  6. Microbial interactions: ecology in a molecular perspective.

    Science.gov (United States)

    Braga, Raíssa Mesquita; Dourado, Manuella Nóbrega; Araújo, Welington Luiz

    2016-12-01

    The microorganism-microorganism or microorganism-host interactions are the key strategy to colonize and establish in a variety of different environments. These interactions involve all ecological aspects, including physiochemical changes, metabolite exchange, metabolite conversion, signaling, chemotaxis and genetic exchange resulting in genotype selection. In addition, the establishment in the environment depends on the species diversity, since high functional redundancy in the microbial community increases the competitive ability of the community, decreasing the possibility of an invader to establish in this environment. Therefore, these associations are the result of a co-evolution process that leads to the adaptation and specialization, allowing the occupation of different niches, by reducing biotic and abiotic stress or exchanging growth factors and signaling. Microbial interactions occur by the transference of molecular and genetic information, and many mechanisms can be involved in this exchange, such as secondary metabolites, siderophores, quorum sensing system, biofilm formation, and cellular transduction signaling, among others. The ultimate unit of interaction is the gene expression of each organism in response to an environmental (biotic or abiotic) stimulus, which is responsible for the production of molecules involved in these interactions. Therefore, in the present review, we focused on some molecular mechanisms involved in the microbial interaction, not only in microbial-host interaction, which has been exploited by other reviews, but also in the molecular strategy used by different microorganisms in the environment that can modulate the establishment and structuration of the microbial community. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  7. Functional genetics of intraspecific ecological interactions in Arabidopsis thaliana

    OpenAIRE

    Wolf, Jason B.; Mutic, Joshua J.; Kover, Paula X.

    2011-01-01

    Studying the genetic basis of traits involved in ecological interactions is a fundamental part of elucidating the connections between evolutionary and ecological processes. Such knowledge allows one to link genetic models of trait evolution with ecological models describing interactions within and between species. Previous work has shown that connections between genetic and ecological processes in Arabidopsis thaliana may be mediated by the fact that quantitative trait loci (QTL) with ‘direct...

  8. [Connotation characterization and evaluation of ecological well-being based on ecosystem service theory.

    Science.gov (United States)

    Zang, Zheng; Zou, Xin- Qing

    2016-04-22

    China is advocating ecological civilization construction nowadays. Further researches on the relation between ecosystem service and humanity well-being are full of theoretical and practical significance. Combining related researches, this paper defined the concept and connotation of ecological well-being based on ecosystem service theory. Referencing theory of national economic accounting and relative researches, the evaluation indicators of ecological well-being supply and consumption were established. The quantitative characterization and evaluation method of red line of regional ecological well-being was proposed on the basis of location quotient. Then the evaluation of ecological well-being in mainland China in 2012 was set as an example for empirical research. The results showed that the net product values of 6 ecosystems, includingcultivated land, forest land, grassland, wetland, water area and unused land, were respectively 1481.925, 8194.806, 4176.277, 4245.760, 3177.084 and 133.762 billion CNY. Spatial heterogeneity of ecosystem net product in different provinces was distinct. Ecological well-being per capita of forest land, grassland, wetland, cultivated land and unused land in eastern and middle provinces were under the red line and less than the national average. The spatial distribution of 9 kinds of ecological well-being per capita split at Hu's line with high value in northwest and low value in southeast, and was aggravated by differences in density of population and land resources gift.

  9. Applications of C and N stable isotopes to ecological and environmental studies in seagrass ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Lepoint, Gilles [Centre MARE, Laboratoire d' Oceanologie, Institut de Chimie, B6, Universite de Liege, B-4000 Liege (Belgium)]. E-mail: g.lepoint@ulg.ac.be; Dauby, Patrick [Centre MARE, Laboratoire d' Oceanologie, Institut de Chimie, B6, Universite de Liege, B-4000 Liege (Belgium); Institut Royal des Sciences Naturelles de Belgique, rue Vautier, B1000 Brussels (Belgium); Gobert, Sylvie [Centre MARE, Laboratoire d' Oceanologie, Institut de Chimie, B6, Universite de Liege, B-4000 Liege (Belgium)

    2004-12-01

    Stable isotopes of carbon and nitrogen are increasingly used in marine ecosystems, for ecological and environmental studies. Here, we examine some applications of stable isotopes as ecological integrators or tracers in seagrass ecosystem studies. We focus on both the use of natural isotope abundance as food web integrators or environmental tracers and on the use of stable isotopes as experimental tools. As ecosystem integrators, stable isotopes have helped to elucidate the general structure of trophic webs in temperate, Mediterranean and tropical seagrass ecosystems. As environmental tracers, stable isotopes have proven their utility in sewage impact measuring and mapping. However, to make such environmental studies more comprehensible, future works on understanding of basic reasons for variations of N and C stable isotopes in seagrasses should be encouraged. At least, as experimental tracers, stable isotopes allow the study of many aspects of N and C cycles at the scale of a plant or at the scale of the seagrass ecosystem.

  10. Ecosystem process interactions between central Chilean habitats

    Directory of Open Access Journals (Sweden)

    Meredith Root-Bernstein

    2015-01-01

    Full Text Available Understanding ecosystem processes is vital for developing dynamic adaptive management of human-dominated landscapes. We focus on conservation and management of the central Chilean silvopastoral savanna habitat called “espinal”, which often occurs near matorral, a shrub habitat. Although matorral, espinal and native sclerophyllous forest are linked successionally, they are not jointly managed and conserved. Management goals in “espinal” include increasing woody cover, particularly of the dominant tree Acacia caven, improving herbaceous forage quality, and increasing soil fertility. We asked whether adjacent matorral areas contribute to espinal ecosystem processes related to the three main espinal management goals. We examined input and outcome ecosystem processes related to these goals in matorral and espinal with and without shrub understory. We found that matorral had the largest sets of inputs to ecosystem processes, and espinal with shrub understory had the largest sets of outcomes. Moreover, we found that these outcomes were broadly in the directions preferred by management goals. This supports our prediction that matorral acts as an ecosystem process bank for espinal. We recommend that management plans for landscape resilience consider espinal and matorral as a single landscape cover class that should be maintained as a dynamic mosaic. Joint management of espinal and matorral could create new management and policy opportunities.

  11. The Economics of Ecosystems and Biodiversity: Ecological and Economic Foundations.

    OpenAIRE

    John M. Gowdy; Richard Howarth; Clem Tisdell

    2010-01-01

    This chapter presents the economic logic behind the concept of discounting the future and discusses how it applies to biodiversity conservation. How should economists account for the effects of biodiversity and ecosystem losses in the immediate and distant future? We discuss how to integrate traditional cost-benefit analysis with other approaches to understand and measure, where possible, environmental values. We conclude that losses of biodiversity and ecosystems have properties that make it...

  12. Changes in biodiversity and trade-offs among ecosystem services, stakeholders, and components of well-being: the contribution of the International Long-Term Ecological Research network (ILTER to Programme on Ecosystem Change and Society (PECS

    Directory of Open Access Journals (Sweden)

    Manuel Maass

    2016-09-01

    Full Text Available The International Long-Term Ecological Research (ILTER network comprises > 600 scientific groups conducting site-based research within 40 countries. Its mission includes improving the understanding of global ecosystems and informs solutions to current and future environmental problems at the global scales. The ILTER network covers a wide range of social-ecological conditions and is aligned with the Programme on Ecosystem Change and Society (PECS goals and approach. Our aim is to examine and develop the conceptual basis for proposed collaboration between ILTER and PECS. We describe how a coordinated effort of several contrasting LTER site-based research groups contributes to the understanding of how policies and technologies drive either toward or away from the sustainable delivery of ecosystem services. This effort is based on three tenets: transdisciplinary research; cross-scale interactions and subsequent dynamics; and an ecological stewardship orientation. The overarching goal is to design management practices taking into account trade-offs between using and conserving ecosystems toward more sustainable solutions. To that end, we propose a conceptual approach linking ecosystem integrity, ecosystem services, and stakeholder well-being, and as a way to analyze trade-offs among ecosystem services inherent in diverse management options. We also outline our methodological approach that includes: (i monitoring and synthesis activities following spatial and temporal trends and changes on each site and by documenting cross-scale interactions; (ii developing analytical tools for integration; (iii promoting trans-site comparison; and (iv developing conceptual tools to design adequate policies and management interventions to deal with trade-offs. Finally, we highlight the heterogeneity in the social-ecological setting encountered in a subset of 15 ILTER sites. These study cases are diverse enough to provide a broad cross-section of contrasting

  13. Ecosystem-based fishery management: a critical review of concepts and ecological economic models

    DEFF Research Database (Denmark)

    Nguyen, Thanh Viet

      An ecosystem approach means different things to different people. As a result the concept of ecosystem-based fishery management is evolving and it has no universal definition or consistent application. As regards ecosystem modeling, most economic models of fishery ignore the linkages to lower...... trophic levels. In particular, environmental data and other bottom-up information is widely disregarded. The objective of this paper is to provide a critical review of concepts and ecological economic models relating to ecosystem-based fishery management....

  14. The fundamental role of ecological feedback mechanisms for the adaptive management of seagrass ecosystems - a review.

    Science.gov (United States)

    Maxwell, Paul S; Eklöf, Johan S; van Katwijk, Marieke M; O'Brien, Katherine R; de la Torre-Castro, Maricela; Boström, Christoffer; Bouma, Tjeerd J; Krause-Jensen, Dorte; Unsworth, Richard K F; van Tussenbroek, Brigitta I; van der Heide, Tjisse

    2017-08-01

    Seagrass meadows are vital ecosystems in coastal zones worldwide, but are also under global threat. One of the major hurdles restricting the success of seagrass conservation and restoration is our limited understanding of ecological feedback mechanisms. In these ecosystems, multiple, self-reinforcing feedbacks can undermine conservation efforts by masking environmental impacts until the decline is precipitous, or alternatively they can inhibit seagrass recovery in spite of restoration efforts. However, no clear framework yet exists for identifying or dealing with feedbacks to improve the management of seagrass ecosystems. Here we review the causes and consequences of multiple feedbacks between seagrass and biotic and/or abiotic processes. We demonstrate how feedbacks have the potential to impose or reinforce regimes of either seagrass dominance or unvegetated substrate, and how the strength and importance of these feedbacks vary across environmental gradients. Although a myriad of feedbacks have now been identified, the co-occurrence and likely interaction among feedbacks has largely been overlooked to date due to difficulties in analysis and detection. Here we take a fundamental step forward by modelling the interactions among two distinct above- and belowground feedbacks to demonstrate that interacting feedbacks are likely to be important for ecosystem resilience. On this basis, we propose a five-step adaptive management plan to address feedback dynamics for effective conservation and restoration strategies. The management plan provides guidance to aid in the identification and prioritisation of likely feedbacks in different seagrass ecosystems. © 2016 Cambridge Philosophical Society.

  15. Interactions between ecosystems and hydrology in the Loess Plateau

    Science.gov (United States)

    Fu, B.; Wang, S.

    2017-12-01

    The Loess Plateau is located in the arid and semi-arid temperate continental monsoon climatic zone. Large-scale "Grain-for-Green" project has been implemented in the since 1999, which has made remarkable contribution to the soil and water control, but also has led to some negative ecological effects. Understanding the interactions between ecosystems and hydrology is significant for the vegetation carrying capacity assessment and guiding the vegetation restoration. We observed the soil moisture at multiple scales including slope, catchment and transect across Loess Plateau to analyze the effects of land use change and its trend along the precipitation gradient. Remote sensing data also used to capture the spatiotemporal variance of soil moisture in the Loess Plateau, as well as the in-situ measured soil moisture decrease following the massive re-vegetation. We found soil moisture decrease in response to the massive re-vegetation occurred in a transition zone of grass-forest ecosystems with annual precipitation between 450-550 mm. The average runoff in the Loess Plateau also decreased continuously during the period 1961-2009 (average rate of -0.9 mm yr-1, P < 0.001). Human intervention played a dominant role in creating the transition points, Water yield (i.e., the ratio of runoff to precipitation) decreased following each anthropogenic transition, causing a 56% reduction in available freshwater resources during the period 1961-2009. From currently revegetated areas and human water demand, we estimate a threshold of NPP of 400±5 g C m-2 yr-1 above which the population will suffer water shortages. NPP in this region is found to be already close to this limit.

  16. Ecosystem development in roadside grasslands: biotic control, plant–soil interactions and dispersal limitations

    Science.gov (United States)

    García-Palacios, Pablo; Bowker, Matthew A.; Maestre, Fernando T.; Soliveres, Santiago; Valladares, Fernando; Papadopoulos, Jorge; Escudero, Adrián

    2015-01-01

    Roadside grasslands undergoing secondary succession are abundant, and represent ecologically meaningful examples of novel, human-created ecosystems. Interactions between plant and soil communities (hereafter plant–soil interactions) are of major importance in understanding the role of biotic control in ecosystem functioning, but little is known about these links in the context of ecosystem restoration and succession. The assessment of the key biotic communities and interactions driving ecosystem development will help practitioners to better allocate the limited resources devoted to roadside grassland restoration. We surveyed roadside grasslands from three successional stages (0–2, 7–9 and > 20 years) in two Mediterranean regions of Spain. Structural equation modeling was used to evaluate how interactions between plants, biological soil crusts [BSCs], and soil microbial functional diversity [soil microorganisms] affect indicators of ecosystem development and restoration: plant similarity to the reference ecosystem, erosion control and soil C storage and N accumulation. Changes in plant community composition along the successional gradient exerted the strongest influence on these indicators. High BSC cover was associated with high soil stability, and high soil microbial functional diversity from late-successional stages was associated with high soil fertility. Contrary to our expectations, the indirect effects of plants, mediated by either BSCs or soil microorganisms, were very weak in both regions, suggesting a minor role for plant–soil interactions upon ecosystem development indicators over long periods. Our results suggest that natural vegetation dynamics effectively improved ecosystem development within a time frame of 20 years in the grasslands evaluated. They also indicate that this time could be shortened if management actions focus on: 1) maintain well-conserved natural areas close to roadsides to enhance plant compositional changes towards late

  17. An assessment of adherence to basic ecological principles by payments for ecosystem service projects.

    Science.gov (United States)

    Prager, C M; Varga, A; Olmsted, P; Ingram, J C; Cattau, M; Freund, C; Wynn-Grant, R; Naeem, S

    2016-08-01

    Programs and projects employing payments for ecosystem service (PES) interventions achieve their objectives by linking buyers and sellers of ecosystem services. Although PES projects are popular conservation and development interventions, little is known about their adherence to basic ecological principles. We conducted a quantitative assessment of the degree to which a global set of PES projects adhered to four ecological principles that are basic scientific considerations for any project focused on ecosystem management: collection of baseline data, identification of threats to an ecosystem service, monitoring, and attention to ecosystem dynamics or the formation of an adaptive management plan. We evaluated 118 PES projects in three markets-biodiversity, carbon, and water-compiled using websites of major conservation organizations; ecology, economic, and climate-change databases; and three scholarly databases (ISI Web of Knowledge, Web of Science, and Google Scholar). To assess adherence to ecological principles, we constructed two scientific indices (one additive [ASI] and one multiplicative [MSI]) based on our four ecological criteria and analyzed index scores by relevant project characteristics (e.g., sector, buyer, seller). Carbon-sector projects had higher ASI values (P < 0.05) than water-sector projects and marginally higher ASI scores (P < 0.1) than biodiversity-sector projects, demonstrating their greater adherence to ecological principles. Projects financed by public-private partnerships had significantly higher ASI values than projects financed by governments (P < 0.05) and marginally higher ASI values than those funded by private entities (P < 0.1). We did not detect differences in adherence to ecological principles based on the inclusion of cobenefits, the spatial extent of a project, or the size of a project's budget. These findings suggest, at this critical phase in the rapid growth of PES projects, that fundamental ecological principles should be

  18. Toxicity Bioassays for Ecological Risk Assessment in Arid and Semiarid Ecosystems. Reviews Environmental Contamination and Toxicology 168:43-98.

    Energy Technology Data Exchange (ETDEWEB)

    Markwiese, J.T.; Ryti, R.T.; Hooten, M.M.; Michael, D.I.; Hlohowskyj, I.

    2001-02-01

    This paper discusses current limitations for performing ecological risk assessments in dry environments (i.e., ecosystems that are characteristic of many DOE Facilities) and presents novel approaches to addressing ecological risk in such systems.

  19. Toxicity Bioassays for Ecological Risk Assessment in Arid and Semiarid Ecosystems. Reviews Environmental Contamination and Toxicology 168:43-98

    International Nuclear Information System (INIS)

    Markwiese, J.T.; Ryti, R.T.; Hooten, M.M.; Michael, D.I.; Hlohowskyj, I.

    2001-01-01

    This paper discusses current limitations for performing ecological risk assessments in dry environments (i.e., ecosystems that are characteristic of many DOE Facilities) and presents novel approaches to addressing ecological risk in such systems

  20. Imaging spectroscopy for ecological analysis in forest and grassland ecosystems

    NARCIS (Netherlands)

    Homolova, L.

    2014-01-01

    Terrestrial vegetation is an important component of the Earth’s biosphere and therefore playing an essential role in climate regulation, carbon sequestration, and it provides large variety of services to humans. For a sustainable management of terrestrial ecosystems it is essential to understand

  1. Credit of ecological interactions: A new conceptual framework to support conservation in a defaunated world.

    Science.gov (United States)

    Genes, Luísa; Cid, Bruno; Fernandez, Fernando A S; Pires, Alexandra S

    2017-03-01

    As defaunation spreads through the world, there is an urgent need for restoring ecological interactions, thus assuring ecosystem processes. Here, we define the new concept of credit of ecological interactions , as the number of interactions that can be restored in a focal area by species colonization or reintroduction. We also define rewiring time , as the time span until all the links that build the credit of ecological interactions of a focal area have become functional again. We expect that the credit will be gradually cashed following refaunation in rates that are proportional to (1) the abundance of the reintroduced species (that is expected to increase in time since release), (2) the abundance of the local species that interact with them, and (3) the traits of reintroduced species. We illustrated this approach using a theoretical model and an empirical case study where the credit of ecological interactions was estimated. This new conceptual framework is useful for setting reintroduction priorities and for evaluating the success of conservation initiatives that aim to restore ecosystem services.

  2. Coprolites reveal ecological interactions lost with the extinction of New Zealand birds.

    Science.gov (United States)

    Boast, Alexander P; Weyrich, Laura S; Wood, Jamie R; Metcalf, Jessica L; Knight, Rob; Cooper, Alan

    2018-02-13

    Over the past 50,000 y, biotic extinctions and declines have left a legacy of vacant niches and broken ecological interactions across global terrestrial ecosystems. Reconstructing the natural, unmodified ecosystems that preceded these events relies on high-resolution analyses of paleoecological deposits. Coprolites are a source of uniquely detailed information about trophic interactions and the behaviors, gut parasite communities, and microbiotas of prehistoric animal species. Such insights are critical for understanding the legacy effects of extinctions on ecosystems, and can help guide contemporary conservation and ecosystem restoration efforts. Here we use high-throughput sequencing (HTS) of ancient eukaryotic DNA from coprolites to reconstruct aspects of the biology and ecology of four species of extinct moa and the critically endangered kakapo parrot from New Zealand (NZ). Importantly, we provide evidence that moa and prehistoric kakapo consumed ectomycorrhizal fungi, suggesting these birds played a role in dispersing fungi that are key to NZ's natural forest ecosystems. We also provide the first DNA-based evidence that moa frequently supplemented their broad diets with ferns and mosses. Finally, we also find parasite taxa that provide insight into moa behavior, and present data supporting the hypothesis of coextinction between moa and several parasite species. Our study demonstrates that HTS sequencing of coprolites provides a powerful tool for resolving key aspects of ancient ecosystems and may rapidly provide information not obtainable by conventional paleoecological techniques, such as fossil analyses.

  3. Bridging food webs, ecosystem metabolism, and biogeochemistry using ecological stoichiometry theory

    DEFF Research Database (Denmark)

    Welti, Nina; Striebel, Maren; Ulseth, Amber J.

    2017-01-01

    process rates). ES theory holds the promise to be a unifying concept to link across hierarchical scales of patterns and processes in ecology, but this has not been fully achieved. Therefore, we propose connecting the expertise of aquatic ecologists and biogeochemists with ES theory as a common currency......, we propose that using ES to link nutrient cycling, trophic dynamics, and ecosystem metabolism would allow for a more holistic understanding of ecosystem functions in a changing environment....

  4. Proceedings of the first international congress of ecology: structure, functioning, and management of ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    1974-01-01

    Ninety-six papers were presented; one paper, dealing with ecosystems stability, was abstracted and indexed separately for Energy Research Abstracts. Other subjects included are of interest to limnologists, biologists, botanists, zoologists, microbiologists, and agriculturists. An interdiscipline approach discussed subjects such as energy flow, productivity, diversity, stability and maturity from their different points of view. Special reports are included on systems analysis, remote sensing and methods of experimentation with ecosystems. Biological control, parasitic system, aerobiology and human ecology are also treated in relation to general ecology. Tropical forests are treated with ecological consequences of deforestation for vegetation, soil and aquatic systems in the tropics. In these proceedings, contributions to the plenary sessions are represented only in the form of abstracts. Full texts and summaries of the discussions will be published in a separate book: Unifying Concepts of Ecology. (PCS)

  5. Does ecosystem variability explain phytoplankton diversity? Solving an ecological puzzle with long-term data sets

    Science.gov (United States)

    Sarker, Subrata; Lemke, Peter; Wiltshire, Karen H.

    2018-05-01

    Explaining species diversity as a function of ecosystem variability is a long-term discussion in community-ecology research. Here, we aimed to establish a causal relationship between ecosystem variability and phytoplankton diversity in a shallow-sea ecosystem. We used long-term data on biotic and abiotic factors from Helgoland Roads, along with climate data to assess the effect of ecosystem variability on phytoplankton diversity. A point cumulative semi-variogram method was used to estimate the long-term ecosystem variability. A Markov chain model was used to estimate dynamical processes of species i.e. occurrence, absence and outcompete probability. We identified that the 1980s was a period of high ecosystem variability while the last two decades were comparatively less variable. Ecosystem variability was found as an important predictor of phytoplankton diversity at Helgoland Roads. High diversity was related to low ecosystem variability due to non-significant relationship between probability of a species occurrence and absence, significant negative relationship between probability of a species occurrence and probability of a species to be outcompeted by others, and high species occurrence at low ecosystem variability. Using an exceptional marine long-term data set, this study established a causal relationship between ecosystem variability and phytoplankton diversity.

  6. An ecosystem services approach to the ecological effects of salvage logging: valuation of seed dispersal.

    Science.gov (United States)

    Leverkus, Alexandro B; Castro, Jorge

    2017-06-01

    Forest disturbances diminish ecosystem services and boost disservices. Because post-disturbance management intends to recover the greatest possible value, selling timber often prevails over other considerations. Ecological research has shown diverse effects of salvage logging, yet such research has focused on the biophysical component of post-disturbance ecosystems and lacks the link with human well-being. Here we bridge that gap under the ecosystem services framework by assessing the impact of post-fire management on a non-timber value. By employing the replacement cost method, we calculated the value of the post-fire natural regeneration of Holm oaks in southern Spain under three post-fire management options by considering the cost of planting instead. The value of this ecosystem service in non-intervention areas doubled that of salvage-logged stands due to the preference for standing dead trees by the main seed disperser. Still, most of the value resulted from the resprouting capacity of oaks. The value of this and other ecosystem services should be added to traditional cost/benefit analyses of post-disturbance management. We thus call for a more holistic approach to salvage logging research, one that explicitly links ecological processes with human well-being through ecosystem services, to better inform decision-makers on the outcomes of post-disturbance management. © 2017 by the Ecological Society of America.

  7. Benthic macroinvertebrates as ecological indicators for estuarine and coastal ecosystems : assessment and intercalibration

    OpenAIRE

    Teixeira, Heliana Lilita Gonçalves

    2010-01-01

    Tese de doutoramento em Biologia (Ecologia) apresentada à Faculdade de Ciências e Tecnologia da Universidade de Coimbra The aim of the research work presented in this thesis is to be a contribution to the field of ecological assessment in coastal and transitional ecosystems. The main goals were: a) to present a method for the assessment of the ecological status of benthic macroinvertebrate communities in Portuguese transitional waters that would meet the requirements of the Eur...

  8. River basins as social-ecological systems: linking levels of societal and ecosystem water metabolism in a semiarid watershed

    Directory of Open Access Journals (Sweden)

    Violeta Cabello

    2015-09-01

    Full Text Available River basin modeling under complexity requires analytical frameworks capable of dealing with the multiple scales and dimensions of environmental problems as well as uncertainty in the evolution of social systems. Conceptual and methodological developments can now be framed using the wide socio-eco-hydrological approach. We add hierarchy theory into the mix to discuss the conceptualization of river basins as complex, holarchic social-ecological systems. We operationalize the social-ecological systems water metabolism framework in a semiarid watershed in Spain, and add the governance dimension that shapes human-environment reciprocity. To this purpose, we integrate an eco-hydrological model with the societal metabolism accounting scheme for land use, human activity, and water use. We explore four types of interactions: between societal organization and water uses/demands, between ecosystem organization and their water requirements/supplies, between societal metabolism and aquatic ecosystem health, and between water demand and availability. Our results reveal a metabolic pattern of a high mountain rural system striving to face exodus and agricultural land abandonment with a multifunctional economy. Centuries of social-ecological evolution shaping waterscapes through traditional water management practices have influenced the eco-hydrological functioning of the basin, enabling adaptation to aridity. We found a marked spatial gradient on water supply, use pattern, and impact on water bodies from the head to the mouth of the basin. Management challenges posed by the European water regulatory framework as a new driver of social-ecological change are highlighted.

  9. Biogeochemistry and ecology of terrestrial ecosystems of Amazonia

    Science.gov (United States)

    Malhi, Yadvinder; Davidson, Eric A.

    The last decade of research associated with the Large-Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) has led to substantial advances in our understanding of the biogeochemistry and ecology of Amazonian forests and savannas, in particular in relation to the carbon cycle of Amazonia. In this chapter, we present a synthesis of results and ideas that are presented in more detail in subsequent chapters, drawing together evidence from studies of forest ecology, ecophysiology, trace gas fluxes and atmospheric flux towers, large-scale rainfall manipulation experiments and soil surveys, satellite remote sensing, and quantification of carbon and nutrient stocks and flows. The studies have demonstrated the variability of the functioning and biogeochemistry of Amazonian forests at a range of spatial and temporal scales, and they provide clues as to how Amazonia will respond to ongoing direct pressure and global atmospheric change. We conclude by highlighting key questions for the next decade of research to address.

  10. Social-ecological enabling conditions for payments for ecosystem services

    OpenAIRE

    Heidi R. Huber-Stearns; Drew E. Bennett; Stephen Posner; Ryan C. Richards; Jenn Hoyle. Fair; Stella J. M. Cousins; Chelsie L. Romulo

    2017-01-01

    The concept of "enabling conditions" centers on conditions that facilitate approaches to addressing social and ecological challenges. Although multiple fields have independently addressed the concept of enabling conditions, the literature lacks a shared understanding or integration of concepts. We propose a more synthesized understanding of enabling conditions beyond disciplinary boundaries by focusing on the enabling conditions that influence the implementation of a range of environmental p...

  11. Social interactions among grazing reef fish drive material flux in a coral reef ecosystem.

    Science.gov (United States)

    Gil, Michael A; Hein, Andrew M

    2017-05-02

    In human financial and social systems, exchanges of information among individuals cause speculative bubbles, behavioral cascades, and other correlated actions that profoundly influence system-level function. Exchanges of information are also widespread in ecological systems, but their effects on ecosystem-level processes are largely unknown. Herbivory is a critical ecological process in coral reefs, where diverse assemblages of fish maintain reef health by controlling the abundance of algae. Here, we show that social interactions have a major effect on fish grazing rates in a reef ecosystem. We combined a system for observing and manipulating large foraging areas in a coral reef with a class of dynamical decision-making models to reveal that reef fish use information about the density and actions of nearby fish to decide when to feed on algae and when to flee foraging areas. This "behavioral coupling" causes bursts of feeding activity that account for up to 68% of the fish community's consumption of algae. Moreover, correlations in fish behavior induce a feedback, whereby each fish spends less time feeding when fewer fish are present, suggesting that reducing fish stocks may not only reduce total algal consumption but could decrease the amount of algae each remaining fish consumes. Our results demonstrate that social interactions among consumers can have a dominant effect on the flux of energy and materials through ecosystems, and our methodology paves the way for rigorous in situ measurements of the behavioral rules that underlie ecological rates in other natural systems.

  12. Combining ecosystem services assessment with structured decision making to support ecological restoration planning.

    Science.gov (United States)

    Martin, David M; Mazzotta, Marisa; Bousquin, Justin

    2018-04-10

    Accounting for ecosystem services in environmental decision making is an emerging research topic. Modern frameworks for ecosystem services assessment emphasize evaluating the social benefits of ecosystems, in terms of who benefits and by how much, to aid in comparing multiple courses of action. Structured methods that use decision analytic-approaches are emerging for the practice of ecological restoration. In this article, we combine ecosystem services assessment with structured decision making to estimate and evaluate measures of the potential benefits of ecological restoration with a case study in the Woonasquatucket River watershed, Rhode Island, USA. We partnered with a local watershed management organization to analyze dozens of candidate wetland restoration sites for their abilities to supply five ecosystem services-flood water retention, scenic landscapes, learning opportunities, recreational opportunities, and birds. We developed 22 benefit indicators related to the ecosystem services as well as indicators for social equity and reliability that benefits will sustain in the future. We applied conceptual modeling and spatial analysis to estimate indicator values for each candidate restoration site. Lastly, we developed a decision support tool to score and aggregate the values for the organization to screen the restoration sites. Results show that restoration sites in urban areas can provide greater social benefits than sites in less urban areas. Our research approach is general and can be used to investigate other restoration planning studies that perform ecosystem services assessment and fit into a decision-making process.

  13. Digital Ecology: Coexistence and Domination among Interacting Networks

    Science.gov (United States)

    Kleineberg, Kaj-Kolja; Boguñá, Marián

    2015-05-01

    The overwhelming success of Web 2.0, within which online social networks are key actors, has induced a paradigm shift in the nature of human interactions. The user-driven character of Web 2.0 services has allowed researchers to quantify large-scale social patterns for the first time. However, the mechanisms that determine the fate of networks at the system level are still poorly understood. For instance, the simultaneous existence of multiple digital services naturally raises questions concerning which conditions these services can coexist under. Analogously to the case of population dynamics, the digital world forms a complex ecosystem of interacting networks. The fitness of each network depends on its capacity to attract and maintain users’ attention, which constitutes a limited resource. In this paper, we introduce an ecological theory of the digital world which exhibits stable coexistence of several networks as well as the dominance of an individual one, in contrast to the competitive exclusion principle. Interestingly, our theory also predicts that the most probable outcome is the coexistence of a moderate number of services, in agreement with empirical observations.

  14. The estimate of ecological risk for ground ecosystems in case of nuclear power plant failures

    International Nuclear Information System (INIS)

    Kremlenkov, D.Y.; Kremlenkov, M.Y.

    2003-01-01

    Full text: The stochastic nature of radiation damage generates a need of forecasting information about possible consequences for environment and people. In this article it is given the estimate of probable damage to forest-and agricultural ecosystems from radionuclide emergency pollution in case of nuclear plant failures (for early emergency period). This estimate is based on radio-ecological risk conception which provide with the application of radioactive substances distribution models in atmosphere, as were calculation of absorbent radiation dose in critical ecosystem groups-calculation of probable area of lost ecosystems has been done by using the program written in Pascal. The quantitative estimate of environmental loss has been conducted for diverse classes of atmospheric stability. The value of ecological dose range (ELD) to coniferous forest is 30 Gy, deciduous forest - 300 Gy, agricultural crop - 60 Gy. The value of minimum ecological dose range (MELD) for all ecosystems is 10 Gy. In dose spread from MELD to ELD the ecological damage is proportional to absorbed dose. The ecological damage to ground ecosystems caused by cesium-137 and strontium-90 emergency pollution is primarily depended on the scale of radionuclide emergency pollution as well as weather conditions and radio-stability of critical vegetal ecosystem groups. On the assumption of a dose spread from MELD to ELD, ecological risk defined in probable ecosystem's destruction area is estimated: for cesium-137 pollution about 2 % of coniferous forest and from 4 to 9 % of deciduous forest; for strontium-90 pollution from 2 to 4 % of agricultural crop. As the scale of cesium-137 emergency pollution rise from 10 4 to 10 5 Cu the probable damage determined in ecosystem's destruction area increase 12-19 times to coniferous forest ecosystem and 15-36 times to deciduous forest according to weather conditions. The probable damage to coniferous and deciduous forest rise 11-17 times in proportion as the scale

  15. Biodiversity and Ecosystem Functioning: Exploring Principles of Ecology with Agricultural Plants

    Science.gov (United States)

    Ruesink, Jennifer; O'Connor, Eileen; Sparks, Grace

    2006-01-01

    To date, little of the ecological research on biological diversity and ecosystem functioning has been carried out in agricultural systems, despite the fact that agriculture is a major contributor to loss of native habitats and species. However, agricultural research has demonstrated that polycultures of multiple crop species can have higher total…

  16. Program on ecosystem change and society: An international research strategy for integrated social-ecological systems

    NARCIS (Netherlands)

    Carpenter, S.R.; Folke, C.; Norström, A.V.; Olsson, O.; Schultz, L.; Agarwal, B.; Balvanera, P.; Campbell, B.; Castilla, J.C.; Cramer, W.; DeFries, R.; Eyzaguirre, P.; Hughes, T.P.; Polasky, S.; Sanusi, Z.A.; Scholes, R.J.; Spierenburg, M.J.

    2012-01-01

    The Program on Ecosystem Change and Society (PECS), a new initiative within the ICSU global change programs, aims to integrate research on the stewardship of social-ecological systems, the services they generate, and the relationships among natural capital, human wellbeing, livelihoods, inequality

  17. Program on ecosystem change and society: an international research strategy for integrated social–ecological systems

    NARCIS (Netherlands)

    Carpenter, S.R; Folke, C.; Nordström, A.; Olsson, O.; Schultz, L.; Agarwal, B.; Balvanera, P.; Campbell, B.; Castilla, J.C.; Cramer, W.; DeFries, R.; Eyzaguirre, P.; Hughes, T.P.; Polasky, S.; Sanusi, Z.; Spierenburg, M.J.

    2012-01-01

    The Program on Ecosystem Change and Society (PECS), a new initiative within the ICSU global change programs, aims to integrate research on the stewardship of social-ecological systems, the services they generate, and the relationships among natural capital, human wellbeing, livelihoods, inequality

  18. Ecological economic simulation model of mountain fynbos ecosystems - dynamics, valuation and management

    CSIR Research Space (South Africa)

    Higgins, SI

    1997-08-01

    Full Text Available Mountain fynbos ecosystems in South Africa are threatened by alien plant invasions and by a lack of funding for effective management of these invasions. This paper develops an ecological-economic argument for the effective management of plant...

  19. Nitrogen deposition effects on Mediterranean-type ecosystems: An ecological assessment

    Science.gov (United States)

    R. Ochoa-Hueso; E.B. Allen; C. Branquinho; C. Cruz; T. Dias; Mark Fenn; E. Manrique; M.E. Pérez-Corona; L.J. Sheppard; W.D. Stock

    2011-01-01

    We review the ecological consequences of N deposition on the five Mediterranean regions of the world. Seasonality of precipitation and fires regulate the N cycle in these water-limited ecosystems, where dry N deposition dominates. Nitrogen accumulation in soils and on plant surfaces results in peaks of availability with the first winter rains. Decoupling between N...

  20. Ecological community traits and traditional knowledge shape palm ecosystem services in northwestern South America

    DEFF Research Database (Denmark)

    Cámara-Leret, Rodrigo; Paniagua-Zambrana, Narel; Balslev, Henrik

    2014-01-01

    Tropical rainforest ecosystems support the maximum expression of biocultural diversity on Earth and preserving them requires understanding and working with the needs of their inhabitants. Here, we com- bine traditional knowledge with ecological data to quantify cross-scale variation in the ecosys...

  1. Climate-driven changes in the ecological stoichiometry of aquatic ecosystems

    NARCIS (Netherlands)

    van de Waal, D.B.; Verschoor, A.M.; Verspagen, J.M.H.; van Donk, E.; Huisman, J.

    2010-01-01

    Advances in ecological stoichiometry, a rapidly expanding research field investigating the elemental composition of organisms and their environment, have shed new light on the impacts of climate change on freshwater and marine ecosystems. Current changes in the Earth's climate alter the availability

  2. Learning Ecosystem Complexity: A Study on Small-Scale Fishers' Ecological Knowledge Generation

    Science.gov (United States)

    Garavito-Bermúdez, Diana

    2018-01-01

    Small-scale fisheries are learning contexts of importance for generating, transferring and updating ecological knowledge of natural environments through everyday work practices. The rich knowledge fishers have of local ecosystems is the result of the intimate relationship fishing communities have had with their natural environments across…

  3. Optimising the management of complex dynamic ecosystems. An ecological-economic modelling approach

    NARCIS (Netherlands)

    Hein, L.G.

    2005-01-01

    Keywords: ecological-economic modelling; ecosystem services; resource use; efficient; sustainability; wetlands, rangelands.

  4. Mimicking natural ecosystems to develop sustainable supply chains : A theory of socio-ecological intergradation

    NARCIS (Netherlands)

    Gruner, Richard L.; Power, Damien

    2017-01-01

    For most firms, the development of sustainable supply chain practices remains challenging. Using a theory-building approach, we develop a theory of socio-ecological intergradation to provide managers with guidance in mimicking natural ecosystems to develop more local and thus sustainable supply

  5. How the Second Law of Thermodynamics Has Informed Ecosystem Ecology through Its History

    Science.gov (United States)

    Chapman, E. J.; Childers, D. L.; Vallino, J. J.

    2014-12-01

    Throughout the history of ecosystem ecology many attempts have been made to develop a general principle governing how systems develop and organize. We reviewed the historical developments that led to conceptualization of several goal-oriented principles in ecosystem ecology and the relationships among them. We focused our review on two prominent principles—the Maximum Power Principle and the Maximum Entropy Production Principle—and the literature that applies to both. While these principles have considerable conceptual overlap and both use concepts in physics (power and entropy), we found considerable differences in their historical development, the disciplines that apply these principles, and their adoption in the literature. We reviewed the literature using Web of Science keyword searches for the MPP, the MEPP, as well as for papers that cited pioneers in the MPP and the MEPP development. From the 6000 papers that our keyword searches returned, we limited our further meta-analysis to 32 papers by focusing on studies with a foundation in ecosystems research. Despite these seemingly disparate pasts, we concluded that the conceptual approaches of these two principles were more similar than dissimilar and that maximization of power in ecosystems occurs with maximum entropy production. We also found that these two principles have great potential to explain how systems develop, organize, and function, but there are no widely agreed upon theoretical derivations for the MEPP or the MPP, possibly hindering their broader use in ecological research. We end with recommendations for how ecosystems-level studies may better use these principles.

  6. Uranium bioaccumulation in a freshwater ecosystem: Impact of feeding ecology

    Energy Technology Data Exchange (ETDEWEB)

    Kraemer, Lisa D., E-mail: lisakraemer@trentu.ca [Trent University, 1600 West Bank Drive, Peterborough, ON, K9J 7B8 (Canada); Evans, Douglas [Trent University, 1600 West Bank Drive, Peterborough, ON, K9J 7B8 (Canada)

    2012-11-15

    Uranium bioaccumulation in a lake that had been historically affected by a U mine and (2) to use a combined approach of gut content examination and stable nitrogen and carbon isotope analysis to determine if U bioaccumulation in fish was linked to foodweb ecology. We collected three species of fish: smallmouth bass (Micropterus dolomieu), yellow perch (Perca flavescens) and bluegill (Lepomis macrochirus), in addition to several invertebrate species including freshwater bivalves (family: Sphaeriidae), dragonfly nymphs (order: Odonata), snails (class: Gastropoda) and zooplankton (family: Daphniidae). Results showed significant U bioaccumulation in the lake impacted by historical mining activities. Uranium accumulation was 2-3 orders of magnitude higher in invertebrates than in the fish species. Within fish, U was measured in operculum (bone), liver and muscle tissue and accumulation followed the order: operculum > liver > muscle. There was a negative relationship between stable nitrogen ratios ({sup 15}N/{sup 14}N) and U bioaccumulation, suggesting U biodilution in the foodweb. Uranium bioaccumulation in all three tissues (bone, liver, muscle) varied among fish species in a consistent manner and followed the order: bluegill > yellow perch > smallmouth bass. Collectively, gut content and stable isotope analysis suggests that invertebrate-consuming fish species (i.e. bluegill) have the highest U levels, while fish species that were mainly piscivores (i.e. smallmouth bass) have the lowest U levels. Our study highlights the importance of understanding the feeding ecology of fish when trying to predict U accumulation.

  7. Ecological conversion efficiency and its influencers in twelve species of fish in the Yellow Sea Ecosystem

    Science.gov (United States)

    Tang, Qisheng; Guo, Xuewu; Sun, Yao; Zhang, Bo

    2007-09-01

    The ecological conversion efficiencies in twelve species of fish in the Yellow Sea Ecosystem, i.e., anchovy ( Engraulis japonicus), rednose anchovy ( Thrissa kammalensis), chub mackerel ( Scomber japonicus), halfbeak ( Hyporhamphus sajori), gizzard shad ( Konosirus punctatus), sand lance ( Ammodytes personatus), red seabream ( Pagrus major), black porgy ( Acanthopagrus schlegeli), black rockfish ( Sebastes schlegeli), finespot goby ( Chaeturichthys stigmatias), tiger puffer ( Takifugu rubripes), and fat greenling ( Hexagrammos otakii), were estimated through experiments conducted either in situ or in a laboratory. The ecological conversion efficiencies were significantly different among these species. As indicated, the food conversion efficiencies and the energy conversion efficiencies varied from 12.9% to 42.1% and from 12.7% to 43.0%, respectively. Water temperature and ration level are the main factors influencing the ecological conversion efficiencies of marine fish. The higher conversion efficiency of a given species in a natural ecosystem is acquired only under the moderate environment conditions. A negative relationship between ecological conversion efficiency and trophic level among ten species was observed. Such a relationship indicates that the ecological efficiency in the upper trophic levels would increase after fishing down marine food web in the Yellow Sea ecosystem.

  8. Balkanized research in ecological engineering revealed by a bibliometric analysis of earthworms and ecosystem services.

    Science.gov (United States)

    Blouin, Manuel; Sery, Nicolas; Cluzeau, Daniel; Brun, Jean-Jacques; Bédécarrats, Alain

    2013-08-01

    Energy crisis, climate changes, and biodiversity losses have reinforced the drive for more ecologically-based approaches for environmental management. Such approaches are characterized by the use of organisms rather than energy-consuming technologies. Although earthworms are believed to be potentially useful organisms for managing ecosystem services, there is actually no quantification of such a trend in literature. This bibliometric analysis aimed to measure the evolution of the association of "earthworms" and other terms such as ecosystem services (primary production, nutrient cycling, carbon sequestration, soil structure, and pollution remediation), "ecological engineering" or "biodiversity," to assess their convergence or divergence through time. In this aim, we calculated the similarity index, an indicator of the paradigmatic proximity defined in applied epistemology, for each year between 1900 and 2009. We documented the scientific fields and the geographical origins of the studies, as well as the land uses, and compare these characteristics with a 25 years old review on earthworm management. The association of earthworm related keywords with ecosystem services related keywords was increasing with time, reflecting the growing interest in earthworm use in biodiversity and ecosystem services management. Conversely, no significant increase in the association between earthworms and disciplines such as ecological engineering or restoration ecology was observed. This demonstrated that general ecologically-based approaches have yet to emerge and that there is little exchange of knowledge, methods or concepts among balkanized application realms. Nevertheless, there is a strong need for crossing the frontiers between fields of application and for developing an umbrella discipline to provide a framework for the use of organisms to manage ecosystem services.

  9. Morphological and ecological complexity in early eukaryotic ecosystems.

    Science.gov (United States)

    Javaux, E J; Knoll, A H; Walter, M R

    2001-07-05

    Molecular phylogeny and biogeochemistry indicate that eukaryotes differentiated early in Earth history. Sequence comparisons of small-subunit ribosomal RNA genes suggest a deep evolutionary divergence of Eukarya and Archaea; C27-C29 steranes (derived from sterols synthesized by eukaryotes) and strong depletion of 13C (a biogeochemical signature of methanogenic Archaea) in 2,700 Myr old kerogens independently place a minimum age on this split. Steranes, large spheroidal microfossils, and rare macrofossils of possible eukaryotic origin occur in Palaeoproterozoic rocks. Until now, however, evidence for morphological and taxonomic diversification within the domain has generally been restricted to very late Mesoproterozoic and Neoproterozoic successions. Here we show that the cytoskeletal and ecological prerequisites for eukaryotic diversification were already established in eukaryotic microorganisms fossilized nearly 1,500 Myr ago in shales of the early Mesoproterozoic Roper Group in northern Australia.

  10. Microconchids from microbialite ecosystem immediately after end-Permian mass extinction: ecologic selectivity and implications for microbialite ecosystem structure

    Science.gov (United States)

    Yang, H.; Chen, Z.; Wang, Y. B.; Ou, W.; Liao, W.; Mei, X.

    2013-12-01

    The Permian-Triassic (P-Tr) carbonate successions are often characterized by the presence of microbialite buildups worldwide. The widespread microbialites are believed as indication of microbial proliferation immediately after the P-Tr mass extinction. The death of animals representing the primary consumer trophic structure of marine ecosystem in the P-Tr crisis allows the bloom of microbes as an important primary producer in marine trophic food web structure. Thus, the PTB microbialite builders have been regarded as disaster taxa of the P-Tr ecologic crisis. Microbialite ecosystems were suitable for most organisms to inhabit. However, increasing evidence show that microbialite dwellers are also considerably abundant and diverse, including mainly foraminifers Earlandia sp. and Rectocornuspira sp., lingulid brachiopods, ostrocods, gastropods, and microconchids. In particular, ostracods are extremely abundant in this special ecosystem. Microconchid-like calcareous tubes are also considerably abundant. Here, we have sampled systematically a PTB microbialite deposit from the Dajiang section, southern Guizhou Province, southwest China and have extracted abundant isolated specimens of calcareous worm tubes. Quantitative analysis enables to investigate stratigraphic and facies preferences of microconchids in the PTB microbialites. Our preliminary result indicates that three microconchid species Microconchus sp., Helicoconchus elongates and Microconchus aberrans inhabited in microbialite ecosystem. Most microconchilds occurred in the upper part of the microbialite buildup and the grainstone-packstone microfacies. Very few microconchilds were found in the rocks bearing well-developed microbialite structures. Their stratigraphic and environmental preferences indicate proliferation of those metazoan organisms is coupled with ebb of the microbialite development. They also proliferated in some local niches in which microbial activities were not very active even if those

  11. Trophic interactions, ecosystem structure and function in the southern Yellow Sea

    Science.gov (United States)

    Lin, Qun; Jin, Xianshi; Zhang, Bo

    2013-01-01

    The southern Yellow Sea is an important fishing ground, providing abundant fishery resources. However, overfishing and climate change have caused a decline in the resource and damaged the ecosystem. We developed an ecosystem model to analyze the trophic interactions and ecosystem structure and function to guide sustainable development of the ecosystem. A trophic mass-balance model of the southern Yellow Sea during 2000-2001 was constructed using Ecopath with Ecosim software. We defined 22 important functional groups and studied their diet composition. The trophic levels of fish, shrimp, crabs, and cephalopods were between 2.78 and 4.39, and the mean trophic level of the fisheries was 3.24. The trophic flows within the food web occurred primarily in the lower trophic levels. The mean trophic transfer efficiency was 8.1%, of which 7.1% was from primary producers and 9.3% was from detritus within the ecosystem. The transfer efficiency between trophic levels II to III to IV to V to >V was 5.0%, 5.7%, 18.5%, and 19.7%-20.4%, respectively. Of the total flow, phytoplankton contributed 61% and detritus contributed 39%. Fishing is defined as a top predator within the ecosystem, and has a negative impact on most commercial species. Moreover, the ecosystem had a high gross efficiency of the fishery and a high value of primary production required to sustain the fishery. Together, our data suggest there is high fishing pressure in the southern Yellow Sea. Based on analysis of Odum's ecological parameters, this ecosystem was at an immature stage. Our results provide some insights into the structure and development of this ecosystem.

  12. An assessment of long term ecosystem research activities across European socio-ecological gradients.

    Science.gov (United States)

    Metzger, M J; Bunce, R G H; van Eupen, M; Mirtl, M

    2010-06-01

    Integration of European long term ecosystem research (LTER) would provide important support for the management of the pan-European environment and ecosystems, as well as international policy commitments. This does require appropriate coverage of Europe and standardised frameworks and research methods between countries. Emerging interest in socio-ecological systems prompted the present assessment of the distribution of LTER activities across European socio-ecological gradients. This paper presents a European stratification with a 1 km(2) resolution, delineating 48 broad socio-ecological regions. The dataset is based on an existing biogeophysical stratification constructed using multivariate clustering of mainly climatic variables and a newly developed socio-economic stratification based on an economic density indicator. The coverage of European LTER facilities across the socio-ecological gradients is tested using this dataset. The analysis shows two strong biases in the present LTER effort. Firstly, urban and disturbed regions are consistently under-represented, illustrating a bias for traditional ecological research away from human activity. Secondly, the Mediterranean, for which some of the most extreme global change impacts are projected, is receiving comparatively little attention. Both findings can help guide future investment in the European LTER network - and especially in a Long Term Socio-Ecological Research (LTSER) component- to provide a more balanced coverage. This will provide better scientific understanding of pan-European environmental concerns and support the management of natural resources and international policy commitments in the European Union. (c) 2010 Elsevier Ltd. All rights reserved.

  13. The Rise of the Anthroposphere since 50,000 Years: An Ecological Replacement of Megaherbivores by Humans in Terrestrial Ecosystems?

    Directory of Open Access Journals (Sweden)

    Hervé Bocherens

    2018-01-01

    Full Text Available Megaherbivores fulfilled a number of important ecological functions in terrestrial ecosystems and behaved as ecological engineers since 300 million years until around 12,000 years ago. These essential ecological functions include opening vegetation cover, selective seed dispersal and nutrient recycling and spreading. Thanks to these effects, megaherbivores change the vegetation structure where they live, with cascading effects on smaller herbivores and also on climate. The late Pleistocene extinction strongly impacted the megaherbivores almost all over the world and led to the loss of these important ecological functions in terrestrial ecosystems. These functions were partially restored by agriculturist humans through an ecological replacement that occurred through an ecological shift within the species Homo sapiens. A better understanding of the differences and similarities between the ecological impacts of megaherbivores and those of agricultural humans should help to predict the future of terrestrial ecosystems.

  14. Organism-Sediment Interactions Govern Post-Hypoxia Recovery of Ecosystem Functioning

    Science.gov (United States)

    Van Colen, Carl; Rossi, Francesca; Montserrat, Francesc; Andersson, Maria G. I.; Gribsholt, Britta; Herman, Peter M. J.; Degraer, Steven; Vincx, Magda; Ysebaert, Tom; Middelburg, Jack J.

    2012-01-01

    Hypoxia represents one of the major causes of biodiversity and ecosystem functioning loss for coastal waters. Since eutrophication-induced hypoxic events are becoming increasingly frequent and intense, understanding the response of ecosystems to hypoxia is of primary importance to understand and predict the stability of ecosystem functioning. Such ecological stability may greatly depend on the recovery patterns of communities and the return time of the system properties associated to these patterns. Here, we have examined how the reassembly of a benthic community contributed to the recovery of ecosystem functioning following experimentally-induced hypoxia in a tidal flat. We demonstrate that organism-sediment interactions that depend on organism size and relate to mobility traits and sediment reworking capacities are generally more important than recovering species richness to set the return time of the measured sediment processes and properties. Specifically, increasing macrofauna bioturbation potential during community reassembly significantly contributed to the recovery of sediment processes and properties such as denitrification, bedload sediment transport, primary production and deep pore water ammonium concentration. Such bioturbation potential was due to the replacement of the small-sized organisms that recolonised at early stages by large-sized bioturbating organisms, which had a disproportionately stronger influence on sediment. This study suggests that the complete recovery of organism-sediment interactions is a necessary condition for ecosystem functioning recovery, and that such process requires long periods after disturbance due to the slow growth of juveniles into adult stages involved in these interactions. Consequently, repeated episodes of disturbance at intervals smaller than the time needed for the system to fully recover organism-sediment interactions may greatly impair the resilience of ecosystem functioning. PMID:23185440

  15. Tritrophic Interactions Mediated by Herbivore-Induced Plant Volatiles: Mechanisms, Ecological Relevance, and Application Potential.

    Science.gov (United States)

    Turlings, Ted C J; Erb, Matthias

    2018-01-07

    Tritrophic interactions between plants, herbivores, and their natural enemies are an integral part of all terrestrial ecosystems. Herbivore-induced plant volatiles (HIPVs) play a key role in these interactions, as they can attract predators and parasitoids to herbivore-attacked plants. Thirty years after this discovery, the ecological importance of the phenomena is widely recognized. However, the primary function of HIPVs is still subject to much debate, as is the possibility of using these plant-produced cues in crop protection. In this review, we summarize the current knowledge on the role of HIPVs in tritrophic interactions from an ecological as well as a mechanistic perspective. This overview focuses on the main gaps in our knowledge of tritrophic interactions, and we argue that filling these gaps will greatly facilitate efforts to exploit HIPVs for pest control.

  16. Social-ecological drivers of multiple ecosystem services: what variables explain patterns of ecosystem services across the Norrström drainage basin?

    Directory of Open Access Journals (Sweden)

    Megan Meacham

    2016-03-01

    Full Text Available In human dominated landscapes many diverse, and often antagonistic, human activities are intentionally and inadvertently determining the supply of various ecosystem services. Understanding how different social and ecological factors shape the availability of ecosystem services is essential for fair and effective policy and management. In this paper, we evaluate how well alternative social-ecological models of human impact on ecosystems explain patterns of 16 ecosystem services (ES across the 62 municipalities of the Norrström drainage basin in Sweden. We test four models of human impact on ecosystems, land use, ecological modernization, ecological footprint, and location theory, and test their ability to predict both individual ES and bundles of ES. We find that different models do best to predict different types of individual ES. Land use is the best model for predicting provisioning services, standing water quality, biodiversity appreciation, and cross-country skiing, while other models work better for the remaining services. However, this range of models is not able to predict some of the cultural ES. ES bundles are predicted worse than individual ES by these models, but provide a clear picture of variation in multiple ecosystem services based on limited information. Based on our results, we offer suggestions on how social-ecological modeling and assessments of ecosystems can be further developed.

  17. Interaction networks, ecological stability, and collective antibiotic tolerance in polymicrobial infections

    Science.gov (United States)

    de Vos, Marjon G. J.; Bollenbach, Tobias

    2017-01-01

    Polymicrobial infections constitute small ecosystems that accommodate several bacterial species. Commonly, these bacteria are investigated in isolation. However, it is unknown to what extent the isolates interact and whether their interactions alter bacterial growth and ecosystem resilience in the presence and absence of antibiotics. We quantified the complete ecological interaction network for 72 bacterial isolates collected from 23 individuals diagnosed with polymicrobial urinary tract infections and found that most interactions cluster based on evolutionary relatedness. Statistical network analysis revealed that competitive and cooperative reciprocal interactions are enriched in the global network, while cooperative interactions are depleted in the individual host community networks. A population dynamics model parameterized by our measurements suggests that interactions restrict community stability, explaining the observed species diversity of these communities. We further show that the clinical isolates frequently protect each other from clinically relevant antibiotics. Together, these results highlight that ecological interactions are crucial for the growth and survival of bacteria in polymicrobial infection communities and affect their assembly and resilience. PMID:28923953

  18. An Assessment of Students' Understanding of Ecosystem Concepts: Conflating Ecological Systems and Cycles

    Science.gov (United States)

    Jordan, Rebecca; Gray, Steven; Demeter, Marylee; Lui, Lei; Hmelo-Silver, Cindy E.

    2009-01-01

    Teaching ecological concepts in schools is important in promoting natural science and environmental education for young learners. Developing educational programs is difficult, however, because of complicated ecological processes operating on multiple levels, the unlimited nature of potential system interactions (given the openness of systems), and…

  19. Shifting species interactions in terrestrial dryland ecosystems under altered water availability and climate change

    Science.gov (United States)

    McCluney, Kevin E.; Belnap, Jayne; Collins, Scott L.; González, Angélica L.; Hagen, Elizabeth M.; Holland, J. Nathaniel; Kotler, Burt P.; Maestre, Fernando T.; Smith, Stanley D.; Wolf, Blair O.

    2012-01-01

    Species interactions play key roles in linking the responses of populations, communities, and ecosystems to environmental change. For instance, species interactions are an important determinant of the complexity of changes in trophic biomass with variation in resources. Water resources are a major driver of terrestrial ecology and climate change is expected to greatly alter the distribution of this critical resource. While previous studies have documented strong effects of global environmental change on species interactions in general, responses can vary from region to region. Dryland ecosystems occupy more than one-third of the Earth's land mass, are greatly affected by changes in water availability, and are predicted to be hotspots of climate change. Thus, it is imperative to understand the effects of environmental change on these globally significant ecosystems. Here, we review studies of the responses of population-level plant-plant, plant-herbivore, and predator-prey interactions to changes in water availability in dryland environments in order to develop new hypotheses and predictions to guide future research. To help explain patterns of interaction outcomes, we developed a conceptual model that views interaction outcomes as shifting between (1) competition and facilitation (plant-plant), (2) herbivory, neutralism, or mutualism (plant-herbivore), or (3) neutralism and predation (predator-prey), as water availability crosses physiological, behavioural, or population-density thresholds. We link our conceptual model to hypothetical scenarios of current and future water availability to make testable predictions about the influence of changes in water availability on species interactions. We also examine potential implications of our conceptual model for the relative importance of top-down effects and the linearity of patterns of change in trophic biomass with changes in water availability. Finally, we highlight key research needs and some possible broader impacts

  20. Non-linear interactions determine the impact of sea-level rise on estuarine benthic biodiversity and ecosystem processes.

    Science.gov (United States)

    Yamanaka, Tsuyuko; Raffaelli, David; White, Piran C L

    2013-01-01

    Sea-level rise induced by climate change may have significant impacts on the ecosystem functions and ecosystem services provided by intertidal sediment ecosystems. Accelerated sea-level rise is expected to lead to steeper beach slopes, coarser particle sizes and increased wave exposure, with consequent impacts on intertidal ecosystems. We examined the relationships between abundance, biomass, and community metabolism of benthic fauna with beach slope, particle size and exposure, using samples across a range of conditions from three different locations in the UK, to determine the significance of sediment particle size beach slope and wave exposure in affecting benthic fauna and ecosystem function in different ecological contexts. Our results show that abundance, biomass and oxygen consumption of intertidal macrofauna and meiofauna are affected significantly by interactions among sediment particle size, beach slope and wave exposure. For macrofauna on less sloping beaches, the effect of these physical constraints is mediated by the local context, although for meiofauna and for macrofauna on intermediate and steeper beaches, the effects of physical constraints dominate. Steeper beach slopes, coarser particle sizes and increased wave exposure generally result in decreases in abundance, biomass and oxygen consumption, but these relationships are complex and non-linear. Sea-level rise is likely to lead to changes in ecosystem structure with generally negative impacts on ecosystem functions and ecosystem services. However, the impacts of sea-level rise will also be affected by local ecological context, especially for less sloping beaches.

  1. Interactive Videos Enhance Learning about Socio-Ecological Systems

    Science.gov (United States)

    Smithwick, Erica; Baxter, Emily; Kim, Kyung; Edel-Malizia, Stephanie; Rocco, Stevie; Blackstock, Dean

    2018-01-01

    Two forms of interactive video were assessed in an online course focused on conservation. The hypothesis was that interactive video enhances student perceptions about learning and improves mental models of social-ecological systems. Results showed that students reported greater learning and attitudes toward the subject following interactive video.…

  2. Interactive effects of climate change and biodiversity loss on ecosystem functioning.

    Science.gov (United States)

    Pires, Aliny P F; Srivastava, Diane S; Marino, Nicholas A C; MacDonald, A Andrew M; Figueiredo-Barros, Marcos Paulo; Farjalla, Vinicius F

    2018-05-01

    Climate change and biodiversity loss are expected to simultaneously affect ecosystems, however research on how each driver mediates the effect of the other has been limited in scope. The multiple stressor framework emphasizes non-additive effects, but biodiversity may also buffer the effects of climate change, and climate change may alter which mechanisms underlie biodiversity-function relationships. Here, we performed an experiment using tank bromeliad ecosystems to test the various ways that rainfall changes and litter diversity may jointly determine ecological processes. Litter diversity and rainfall changes interactively affected multiple functions, but how depends on the process measured. High litter diversity buffered the effects of altered rainfall on detritivore communities, evidence of insurance against impacts of climate change. Altered rainfall affected the mechanisms by which litter diversity influenced decomposition, reducing the importance of complementary attributes of species (complementarity effects), and resulting in an increasing dependence on the maintenance of specific species (dominance effects). Finally, altered rainfall conditions prevented litter diversity from fueling methanogenesis, because such changes in rainfall reduced microbial activity by 58%. Together, these results demonstrate that the effects of climate change and biodiversity loss on ecosystems cannot be understood in isolation and interactions between these stressors can be multifaceted. © 2018 by the Ecological Society of America.

  3. Ecological Diversity of Soil Fauna as Ecosystem Engineers in Small-Holder Cocoa Plantation in South Konawe

    OpenAIRE

    Laode Muhammad Harjoni Kilowasid; Tati Suryati Syamsudin; Franciscus Xaverius Susilo; Endah Sulistyawati

    2012-01-01

    Taxa diversity within soil fauna functional groups can affected ecosystem functioning such as ecosystem engineers,which influence decomposition and nutrient cycling. The objective of this study is to describe ecological diversityvariation within soil fauna as ecosystem engineers in soil ecosystem of cocoa (Theobroma cacao L.) plantation.Sampling was conducted during one year period from five different ages of plantation. Soil fauna removed from soilcore using hand sorting methods. A total of ...

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

    Science.gov (United States)

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

    2012-11-01

    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, it 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 toward a better understanding of the factors governing the emergence and dynamics of polymicrobial interactions.

  5. Managing for interactions between local and global stressors of ecosystems.

    Science.gov (United States)

    Brown, Christopher J; Saunders, Megan I; Possingham, Hugh P; Richardson, Anthony J

    2013-01-01

    Global stressors, including climate change, are a major threat to ecosystems, but they cannot be halted by local actions. Ecosystem management is thus attempting to compensate for the impacts of global stressors by reducing local stressors, such as overfishing. This approach assumes that stressors interact additively or synergistically, whereby the combined effect of two stressors is at least the sum of their isolated effects. It is not clear, however, how management should proceed for antagonistic interactions among stressors, where multiple stressors do not have an additive or greater impact. Research to date has focussed on identifying synergisms among stressors, but antagonisms may be just as common. We examined the effectiveness of management when faced with different types of interactions in two systems--seagrass and fish communities--where the global stressor was climate change but the local stressors were different. When there were synergisms, mitigating local stressors delivered greater gains, whereas when there were antagonisms, management of local stressors was ineffective or even degraded ecosystems. These results suggest that reducing a local stressor can compensate for climate change impacts if there is a synergistic interaction. Conversely, if there is an antagonistic interaction, management of local stressors will have the greatest benefits in areas of refuge from climate change. A balanced research agenda, investigating both antagonistic and synergistic interaction types, is needed to inform management priorities.

  6. Managing for interactions between local and global stressors of ecosystems.

    Directory of Open Access Journals (Sweden)

    Christopher J Brown

    Full Text Available Global stressors, including climate change, are a major threat to ecosystems, but they cannot be halted by local actions. Ecosystem management is thus attempting to compensate for the impacts of global stressors by reducing local stressors, such as overfishing. This approach assumes that stressors interact additively or synergistically, whereby the combined effect of two stressors is at least the sum of their isolated effects. It is not clear, however, how management should proceed for antagonistic interactions among stressors, where multiple stressors do not have an additive or greater impact. Research to date has focussed on identifying synergisms among stressors, but antagonisms may be just as common. We examined the effectiveness of management when faced with different types of interactions in two systems--seagrass and fish communities--where the global stressor was climate change but the local stressors were different. When there were synergisms, mitigating local stressors delivered greater gains, whereas when there were antagonisms, management of local stressors was ineffective or even degraded ecosystems. These results suggest that reducing a local stressor can compensate for climate change impacts if there is a synergistic interaction. Conversely, if there is an antagonistic interaction, management of local stressors will have the greatest benefits in areas of refuge from climate change. A balanced research agenda, investigating both antagonistic and synergistic interaction types, is needed to inform management priorities.

  7. Ecological Security and Ecosystem Services in Response to Land Use Change in the Coastal Area of Jiangsu, China

    Directory of Open Access Journals (Sweden)

    Caiyao Xu

    2016-08-01

    Full Text Available Urbanization, and the resulting land use/cover change, is a primary cause of the degradation of coastal wetland ecosystems. Reclamation projects are seen as a way to strike a balance between socioeconomic development and maintenance of coastal ecosystems. Our aim was to understand the ecological changes to Jiangsu’s coastal wetland resulting from land use change since 1977 by using remote sensing and spatial analyses. The results indicate that: (1 The area of artificial land use expanded while natural land use was reduced, which emphasized an increase in production-orientated land uses at the expense of ecologically important wetlands; (2 It took 34 years for landscape ecological security and 39 years for ecosystem services to regain equilibrium. The coastal reclamation area would recover ecological equilibrium only after a minimum of 30 years; (3 The total ecosystem service value decreased significantly from $2.98 billion per year to $2.31 billion per year from 1977 to 2014. Food production was the only one ecosystem service function that consistently increased, mainly because of government policy; (4 The relationship between landscape ecological security and ecosystem services is complicated, mainly because of the scale effect of landscape ecology. Spatial analysis of changing gravity centers showed that landscape ecological security and ecosystem service quality became better in the north than the south over the study period.

  8. Ecological Performances of Plant Species of Halophilous Hydromorphic Ecosystems

    Directory of Open Access Journals (Sweden)

    Maria Speranza

    2015-12-01

    Full Text Available Coastal wetlands are very special environments, characterized by soils permanently or seasonally saturated by salt or brackish water. They host microorganisms and plants able to adapt to anoxic conditions. This paper proposes a review of recent scientific papers dealing with the study of coastal wetlands from different points of view. Some studies examine the species composition and the pattern of the spatial distribution of plant communities, depending on the depth of the salt water table, as well as on other related factors. A significant number of studies analyse instead the coastal wetlands in their ability for the phytoremediation (phytostabilisation and/or phytoextraction and highlight the importance of interactions between the rhizosphere of the halophytes and the physical environment. Finally, more recent studies consider the plant species of the coastal wetlands as a source of useful products (food, feed, oils and expose the results of promising researches on their cultivation.

  9. Towards More Effective Water Quality Governance : A Review of Social-Economic, Legal and Ecological Perspectives and Their Interactions

    NARCIS (Netherlands)

    van Rijswick, H.F.M.W.|info:eu-repo/dai/nl/099909189; Wuijts, S.; Driessen, P.P.J.|info:eu-repo/dai/nl/069081417

    2018-01-01

    In this article, social-economic, legal and ecological perspectives on effectiveness of water quality governance and their interactions have been studied. Worldwide, authorities are facing the challenge of restoring and preserving aquatic ecosystems in accordance with the United Nations Sustainable

  10. Evolution of nutrient uptake reveals a trade-off in the ecological stoichiometry of plant-herbivore interactions

    NARCIS (Netherlands)

    Branco, P.; Stomp, M.; Egas, M.; Huisman, J.

    2010-01-01

    Nutrient limitation determines the primary production and species composition of many ecosystems. Here we apply an adaptive dynamics approach to investigate evolution of the ecological stoichiometry of primary producers and its implications for plant‐herbivore interactions. The model predicts a

  11. Environmental research programme. Ecological research. Annual report 1995. Urban-industrial landscapes, forests, agricultural landscapes, river and lake landscapes, terrestrial ecosystem research, environmental pollution and health

    International Nuclear Information System (INIS)

    1996-01-01

    In promoting ecology research, the federal ministry of science and technology (BMBF) pursues the aim to enhance understanding of the natural resources indispensable to the life of man, animals and plant societies and their interrelations, and to point out existing scope for action to preserve or replenish them. Consequently, ecology research makes an essential contribution towards effective nature conservancy and environmental protection. The interactions between climate and ecosystems also form an important part of this. With regard to topical environmental issues concerning agricultural landscapes, rivers and lakes, forests and urban-industrial agglomerations, system interrelations in representative ecosystems are investigated. The results are to be embodied in directives for the protection or appropriate use of these ecosystems in order to contribute towards a sustainable development of these types of landscapes. The book also evaluates and assesses which types of nuisances, interventions and modes of use represent hazards for the respective systems. (orig./VHE) [de

  12. Human ecology and environmentalism: Two different approaches to the relationships ecosystem/culture

    International Nuclear Information System (INIS)

    Leon Sicard, Tomas

    2001-01-01

    A comparative analysis of the human ecology focus versus the environmental dimension analysis, emphasizing that the first one does not have theoretical instruments to adequately consider the human action inside the ecosystems, while the second one considers the concept of culture as an explanation of the human niche and then of the environmental problem. It ends with thoughts about the environmental or ecologist conception that is discussed in the Colombian peace negotiations

  13. The roles of large top predators in coastal ecosystems: new insights from long term ecological research

    Science.gov (United States)

    Rosenblatt, Adam E.; Heithaus, Michael R.; Mather, Martha E.; Matich, Philip; Nifong, James C.; Ripple, William J.; Silliman, Brian R.

    2013-01-01

    During recent human history, human activities such as overhunting and habitat destruction have severely impacted many large top predator populations around the world. Studies from a variety of ecosystems show that loss or diminishment of top predator populations can have serious consequences for population and community dynamics and ecosystem stability. However, there are relatively few studies of the roles of large top predators in coastal ecosystems, so that we do not yet completely understand what could happen to coastal areas if large top predators are extirpated or significantly reduced in number. This lack of knowledge is surprising given that coastal areas around the globe are highly valued and densely populated by humans, and thus coastal large top predator populations frequently come into conflict with coastal human populations. This paper reviews what is known about the ecological roles of large top predators in coastal systems and presents a synthesis of recent work from three coastal eastern US Long Term Ecological Research (LTER) sites where long-term studies reveal what appear to be common themes relating to the roles of large top predators in coastal systems. We discuss three specific themes: (1) large top predators acting as mobile links between disparate habitats, (2) large top predators potentially affecting nutrient and biogeochemical dynamics through localized behaviors, and (3) individual specialization of large top predator behaviors. We also discuss how research within the LTER network has led to enhanced understanding of the ecological roles of coastal large top predators. Highlighting this work is intended to encourage further investigation of the roles of large top predators across diverse coastal aquatic habitats and to better inform researchers and ecosystem managers about the importance of large top predators for coastal ecosystem health and stability.

  14. Equivalency of Galápagos giant tortoises used as ecological replacement species to restore ecosystem functions.

    Science.gov (United States)

    Hunter, Elizabeth A; Gibbs, James P; Cayot, Linda J; Tapia, Washington

    2013-08-01

    Loss of key plant-animal interactions (e.g., disturbance, seed dispersal, and herbivory) due to extinctions of large herbivores has diminished ecosystem functioning nearly worldwide. Mitigating for the ecological consequences of large herbivore losses through the use of ecological replacements to fill extinct species' niches and thereby replicate missing ecological functions has been proposed. It is unknown how different morphologically and ecologically a replacement can be from the extinct species and still provide similar functions. We studied niche equivalency between 2 phenotypes of Galápagos giant tortoises (domed and saddlebacked) that were translocated to Pinta Island in the Galápagos Archipelago as ecological replacements for the extinct saddlebacked giant tortoise (Chelonoidis abingdonii). Thirty-nine adult, nonreproductive tortoises were introduced to Pinta Island in May 2010, and we observed tortoise resource use in relation to phenotype during the first year following release. Domed tortoises settled in higher, moister elevations than saddlebacked tortoises, which favored lower elevation arid zones. The areas where the tortoises settled are consistent with the ecological conditions each phenotype occupies in its native range. Saddlebacked tortoises selected areas with high densities of the arboreal prickly pear cactus (Opuntia galapageia) and mostly foraged on the cactus, which likely relied on the extinct saddlebacked Pinta tortoise for seed dispersal. In contrast, domed tortoises did not select areas with cactus and therefore would not provide the same seed-dispersal functions for the cactus as the introduced or the original, now extinct, saddlebacked tortoises. Interchangeability of extant megaherbivores as replacements for extinct forms therefore should be scrutinized given the lack of equivalency we observed in closely related forms of giant tortoises. Our results also demonstrate the value of trial introductions of sterilized individuals to test

  15. Species interactions in the western Baltic Sea: With focus on the ecological role of whiting

    DEFF Research Database (Denmark)

    Ross, Stine Dalmann

    , which potentially prey on and compete for food with whiting. Here, the growth dynamics and feeding ecology of whiting in the western Baltic Sea is investigated and discussed in an ecosystem context. Furthermore, the diet of the harbour porpoise is examined and the interactions between whiting, cod......, implementation of the models in strategic management advice for commercially important fish stocks and protected marine mammals is not common practice. This is due to the lack of sufficient information about species interactions including knowledge about the diet, food intake and growth dynamics. This thesis...

  16. An evaluation of the ecological and environmental security on China's terrestrial ecosystems.

    Science.gov (United States)

    Zhang, Hongqi; Xu, Erqi

    2017-04-11

    With rapid economic growth, industrialization, and urbanization, various ecological and environmental problems occur, which threaten and undermine the sustainable development and domestic survival of China. On the national scale, our progress remains in a state of qualitative or semi-quantitative evaluation, lacking a quantitative evaluation and a spatial visualization of ecological and environmental security. This study collected 14 indictors of water, land, air, and biodiversity securities to compile a spatial evaluation of ecological and environmental security in terrestrial ecosystems of China. With area-weighted normalization and scaling transformations, the veto aggregation (focusing on the limit indicator) and balanced aggregation (measuring balanced performance among different indicators) methods were used to aggregate security evaluation indicators. Results showed that water, land, air, and biodiversity securities presented different spatial distributions. A relatively serious ecological and environmental security crisis was found in China, but presented an obviously spatial variation of security evaluation scores. Hotspot areas at the danger level, which are scattered throughout the entirety of the country, were identified. The spatial diversities and causes of ecological and environmental problems in different regions were analyzed. Spatial integration of regional development and proposals for improving the ecological and environmental security were put forward.

  17. Specific non-monotonous interactions increase persistence of ecological networks.

    Science.gov (United States)

    Yan, Chuan; Zhang, Zhibin

    2014-03-22

    The relationship between stability and biodiversity has long been debated in ecology due to opposing empirical observations and theoretical predictions. Species interaction strength is often assumed to be monotonically related to population density, but the effects on stability of ecological networks of non-monotonous interactions that change signs have not been investigated previously. We demonstrate that for four kinds of non-monotonous interactions, shifting signs to negative or neutral interactions at high population density increases persistence (a measure of stability) of ecological networks, while for the other two kinds of non-monotonous interactions shifting signs to positive interactions at high population density decreases persistence of networks. Our results reveal a novel mechanism of network stabilization caused by specific non-monotonous interaction types through either increasing stable equilibrium points or reducing unstable equilibrium points (or both). These specific non-monotonous interactions may be important in maintaining stable and complex ecological networks, as well as other networks such as genes, neurons, the internet and human societies.

  18. A resilience framework for chronic exposures: water quality and ecosystem services in coastal social-ecological systems

    Science.gov (United States)

    We outline a tailored resilience framework that applies ecosystem service concepts to coastal social-ecological systems (SES) affected by water quality degradation. Unlike acute coastal disturbances such as hurricanes or oil spills, water quality issues, particularly those relate...

  19. Prehistoric Human-environment Interactions and Their Impact on Aquatic Ecosystems

    Science.gov (United States)

    Mackay, H.; Henderson, A. C. G.; van Hardenbroek, M.; Cavers, G.; Crone, A.; Davies, K. L.; Fonville, T. R.; Head, K.; Langdon, P. G.; Matton, R.; McCormick, F.; Murray, E.; Whitehouse, N. J.; Brown, A. G.

    2017-12-01

    One of the first widespread human-environment interactions in Scotland and Ireland occurred 3000 years ago when communities first inhabited wetlands, building artificial islands in lakes called crannogs. The reason behind the development and intermittent occupation of crannogs is unclear. We don't know if they were a response to changes in environment or if they were driven by societal influences. Furthermore, the impact of the construction, settlement and human activities on lake ecosystems is unknown, but is a key example of early anthropogenic signatures on the environment. Our research characterises the prehistoric human-environment interactions associated with crannogs by analysing geochemical and biological signals preserved within the crannog and wetland sediments. Records of anthropogenic activities and environmental change have been produced using lipid biomarkers of faecal matter, sedimentary DNA, and the remains of beetles, aquatic invertebrates (chironomids), siliceous algae (diatoms) and pollen. Results of these analyses reveal settlement occupations occurred in phases from the Iron Age to the Medieval Period. The main effects of occupation on the wetland ecosystems are nutrient-driven increases in productivity and shifts in aquatic species from clear water taxa to those associated with more eutrophic conditions. Crannog abandonment reduces nutrient inputs and therefore levels of aquatic productivity, as evidenced by decreases in the abundance of siliceous algae. Despite returns to pre-settlement nutrient and productivity levels, the lake ecosystems do not recover to their previous ecological state: dominant aquatic invertebrate and siliceous algae taxa shift in response to elevated levels of macrophytes within the lakes. Whilst these phase changes in lake ecosystems highlight their adaptive capacity to environmental change, the temporary human interactions associated with crannogs had persisting environmental impacts that shaped the long

  20. Ecology and evolution of plant–pollinator interactions

    Science.gov (United States)

    Mitchell, Randall J.; Irwin, Rebecca E.; Flanagan, Rebecca J.; Karron, Jeffrey D.

    2009-01-01

    Background Some of the most exciting advances in pollination biology have resulted from interdisciplinary research combining ecological and evolutionary perspectives. For example, these two approaches have been essential for understanding the functional ecology of floral traits, the dynamics of pollen transport, competition for pollinator services, and patterns of specialization and generalization in plant–pollinator interactions. However, as research in these and other areas has progressed, many pollination biologists have become more specialized in their research interests, focusing their attention on either evolutionary or ecological questions. We believe that the continuing vigour of a synthetic and interdisciplinary field like pollination biology depends on renewed connections between ecological and evolutionary approaches. Scope In this Viewpoint paper we highlight the application of ecological and evolutionary approaches to two themes in pollination biology: (1) links between pollinator behaviour and plant mating systems, and (2) generalization and specialization in pollination systems. We also describe how mathematical models and synthetic analyses have broadened our understanding of pollination biology, especially in human-modified landscapes. We conclude with several suggestions that we hope will stimulate future research. This Viewpoint also serves as the introduction to this Special Issue on the Ecology and Evolution of Plant–Pollinator Interactions. These papers provide inspiring examples of the synergy between evolutionary and ecological approaches, and offer glimpses of great accomplishments yet to come. PMID:19482881

  1. Ecology and evolution of plant-pollinator interactions.

    Science.gov (United States)

    Mitchell, Randall J; Irwin, Rebecca E; Flanagan, Rebecca J; Karron, Jeffrey D

    2009-06-01

    Some of the most exciting advances in pollination biology have resulted from interdisciplinary research combining ecological and evolutionary perspectives. For example, these two approaches have been essential for understanding the functional ecology of floral traits, the dynamics of pollen transport, competition for pollinator services, and patterns of specialization and generalization in plant-pollinator interactions. However, as research in these and other areas has progressed, many pollination biologists have become more specialized in their research interests, focusing their attention on either evolutionary or ecological questions. We believe that the continuing vigour of a synthetic and interdisciplinary field like pollination biology depends on renewed connections between ecological and evolutionary approaches. In this Viewpoint paper we highlight the application of ecological and evolutionary approaches to two themes in pollination biology: (1) links between pollinator behaviour and plant mating systems, and (2) generalization and specialization in pollination systems. We also describe how mathematical models and synthetic analyses have broadened our understanding of pollination biology, especially in human-modified landscapes. We conclude with several suggestions that we hope will stimulate future research. This Viewpoint also serves as the introduction to this Special Issue on the Ecology and Evolution of Plant-Pollinator Interactions. These papers provide inspiring examples of the synergy between evolutionary and ecological approaches, and offer glimpses of great accomplishments yet to come.

  2. Ecosystem heterogeneity determines the ecological resilience of the Amazon to climate change.

    Science.gov (United States)

    Levine, Naomi M; Zhang, Ke; Longo, Marcos; Baccini, Alessandro; Phillips, Oliver L; Lewis, Simon L; Alvarez-Dávila, Esteban; Segalin de Andrade, Ana Cristina; Brienen, Roel J W; Erwin, Terry L; Feldpausch, Ted R; Monteagudo Mendoza, Abel Lorenzo; Nuñez Vargas, Percy; Prieto, Adriana; Silva-Espejo, Javier Eduardo; Malhi, Yadvinder; Moorcroft, Paul R

    2016-01-19

    Amazon forests, which store ∼ 50% of tropical forest carbon and play a vital role in global water, energy, and carbon cycling, are predicted to experience both longer and more intense dry seasons by the end of the 21st century. However, the climate sensitivity of this ecosystem remains uncertain: several studies have predicted large-scale die-back of the Amazon, whereas several more recent studies predict that the biome will remain largely intact. Combining remote-sensing and ground-based observations with a size- and age-structured terrestrial ecosystem model, we explore the sensitivity and ecological resilience of these forests to changes in climate. We demonstrate that water stress operating at the scale of individual plants, combined with spatial variation in soil texture, explains observed patterns of variation in ecosystem biomass, composition, and dynamics across the region, and strongly influences the ecosystem's resilience to changes in dry season length. Specifically, our analysis suggests that in contrast to existing predictions of either stability or catastrophic biomass loss, the Amazon forest's response to a drying regional climate is likely to be an immediate, graded, heterogeneous transition from high-biomass moist forests to transitional dry forests and woody savannah-like states. Fire, logging, and other anthropogenic disturbances may, however, exacerbate these climate change-induced ecosystem transitions.

  3. Modelling the ecological vulnerability to forest fires in mediterranean ecosystems using geographic information technologies.

    Science.gov (United States)

    Duguy, Beatriz; Alloza, José Antonio; Baeza, M Jaime; De la Riva, Juan; Echeverría, Maite; Ibarra, Paloma; Llovet, Juan; Cabello, Fernando Pérez; Rovira, Pere; Vallejo, Ramon V

    2012-12-01

    Forest fires represent a major driver of change at the ecosystem and landscape levels in the Mediterranean region. Environmental features and vegetation are key factors to estimate the ecological vulnerability to fire; defined as the degree to which an ecosystem is susceptible to, and unable to cope with, adverse effects of fire (provided a fire occurs). Given the predicted climatic changes for the region, it is urgent to validate spatially explicit tools for assessing this vulnerability in order to support the design of new fire prevention and restoration strategies. This work presents an innovative GIS-based modelling approach to evaluate the ecological vulnerability to fire of an ecosystem, considering its main components (soil and vegetation) and different time scales. The evaluation was structured in three stages: short-term (focussed on soil degradation risk), medium-term (focussed on changes in vegetation), and coupling of the short- and medium-term vulnerabilities. The model was implemented in two regions: Aragón (inland North-eastern Spain) and Valencia (eastern Spain). Maps of the ecological vulnerability to fire were produced at a regional scale. We partially validated the model in a study site combining two complementary approaches that focused on testing the adequacy of model's predictions in three ecosystems, all very common in fire-prone landscapes of eastern Spain: two shrublands and a pine forest. Both approaches were based on the comparison of model's predictions with values of NDVI (Normalized Difference Vegetation Index), which is considered a good proxy for green biomass. Both methods showed that the model's performance is satisfactory when applied to the three selected vegetation types.

  4. Quantifying Forest Ecosystem Services Tradeoff—Coupled Ecological and Economic Models

    Science.gov (United States)

    Haff, P. K.; Ling, P. Y.

    2015-12-01

    Quantification of the effect of carbon-related forestland management activities on ecosystem services is difficult, because knowledge about the dynamics of coupled social-ecological systems is lacking. Different forestland management activities, such as various amount, timing, and methods of harvesting, and natural disturbances events, such as wind and fires, create shocks and uncertainties to the forest carbon dynamics. A spatially explicit model, Landis-ii, was used to model the forest succession for different harvest management scenarios at the Grandfather District, North Carolina. In addition to harvest, the model takes into account of the impact of natural disturbances, such as fire and insects, and species competition. The result shows the storage of carbon in standing biomass and in wood product for each species for each scenario. In this study, optimization is used to analyze the maximum profit and the number of tree species that each forest landowner can gain at different prices of carbon, roundwood, and interest rates for different harvest management scenarios. Time series of roundwood production of different types were estimated using remote sensing data. Econometric analysis is done to understand the possible interaction and relations between the production of different types of roundwood and roundwood prices, which can indicate the possible planting scheme that a forest owner may make. This study quantifies the tradeoffs between carbon sequestration, roundwood production, and forest species diversity not only from an economic perspective, but also takes into account of the forest succession mechanism in a species-diverse region. The resulting economic impact on the forest landowners is likely to influence their future planting decision, which in turn, will influence the species composition and future revenue of the landowners.

  5. The relative importance of rapid evolution for plant-microbe interactions depends on ecological context.

    Science.gov (United States)

    Terhorst, Casey P; Lennon, Jay T; Lau, Jennifer A

    2014-06-22

    Evolution can occur on ecological time-scales, affecting community and ecosystem processes. However, the importance of evolutionary change relative to ecological processes remains largely unknown. Here, we analyse data from a long-term experiment in which we allowed plant populations to evolve for three generations in dry or wet soils and used a reciprocal transplant to compare the ecological effect of drought and the effect of plant evolutionary responses to drought on soil microbial communities and nutrient availability. Plants that evolved under drought tended to support higher bacterial and fungal richness, and increased fungal : bacterial ratios in the soil. Overall, the magnitudes of ecological and evolutionary effects on microbial communities were similar; however, the strength and direction of these effects depended on the context in which they were measured. For example, plants that evolved in dry environments increased bacterial abundance in dry contemporary environments, but decreased bacterial abundance in wet contemporary environments. Our results suggest that interactions between recent evolutionary history and ecological context affect both the direction and magnitude of plant effects on soil microbes. Consequently, an eco-evolutionary perspective is required to fully understand plant-microbe interactions.

  6. Accounting for ecosystem services in Life Cycle Assessment, Part II: toward an ecologically based LCA.

    Science.gov (United States)

    Zhang, Yi; Baral, Anil; Bakshi, Bhavik R

    2010-04-01

    Despite the essential role of ecosystem goods and services in sustaining all human activities, they are often ignored in engineering decision making, even in methods that are meant to encourage sustainability. For example, conventional Life Cycle Assessment focuses on the impact of emissions and consumption of some resources. While aggregation and interpretation methods are quite advanced for emissions, similar methods for resources have been lagging, and most ignore the role of nature. Such oversight may even result in perverse decisions that encourage reliance on deteriorating ecosystem services. This article presents a step toward including the direct and indirect role of ecosystems in LCA, and a hierarchical scheme to interpret their contribution. The resulting Ecologically Based LCA (Eco-LCA) includes a large number of provisioning, regulating, and supporting ecosystem services as inputs to a life cycle model at the process or economy scale. These resources are represented in diverse physical units and may be compared via their mass, fuel value, industrial cumulative exergy consumption, or ecological cumulative exergy consumption or by normalization with total consumption of each resource or their availability. Such results at a fine scale provide insight about relative resource use and the risk and vulnerability to the loss of specific resources. Aggregate indicators are also defined to obtain indices such as renewability, efficiency, and return on investment. An Eco-LCA model of the 1997 economy is developed and made available via the web (www.resilience.osu.edu/ecolca). An illustrative example comparing paper and plastic cups provides insight into the features of the proposed approach. The need for further work in bridging the gap between knowledge about ecosystem services and their direct and indirect role in supporting human activities is discussed as an important area for future work.

  7. Cophylogenetic signal is detectable in pollination interactions across ecological scales.

    Science.gov (United States)

    Hutchinson, Matthew C; Cagua, Edgar Fernando; Stouffer, Daniel B

    2017-10-01

    That evolutionary history can influence the way that species interact is a basic tenet of evolutionary ecology. However, when the role of evolution in determining ecological interactions is investigated, focus typically centers on just one side of the interaction. A cophylogenetic signal, the congruence of evolutionary history across both sides of an ecological interaction, extends these previous explorations and provides a more complete picture of how evolutionary patterns influence the way species interact. To date, cophylogenetic signal has most typically been studied in interactions that occur between fine taxonomic clades that show high intimacy. In this study, we took an alternative approach and made an exhaustive assessment of cophylogeny in pollination interactions. To do so, we assessed the strength of cophylogenetic signal at four distinct scales of pollination interaction: (1) across plant-pollinator associations globally, (2) in local pollination communities, (3) within the modular structure of those communities, and (4) in individual modules. We did so using a globally distributed dataset comprised of 54 pollination networks, over 4000 species, and over 12,000 interactions. Within these data, we detected cophylogenetic signal at all four scales. Cophylogenetic signal was found at the level of plant-pollinator interactions on a global scale and in the majority of pollination communities. At the scale defined by the modular structure within those communities, however, we observed a much weaker cophylogenetic signal. Cophylogenetic signal was detectable in a significant proportion of individual modules and most typically when within-module phylogenetic diversity was low. In sum, the detection of cophylogenetic signal in pollination interactions across scales provides a new dimension to the story of how past evolution shapes extant pollinator-angiosperm interactions. © 2017 by the Ecological Society of America.

  8. Context-Specific Trophic and Functional Ecology of Fishes of Small Stream Ecosystems in the Ouachita National Forest

    Science.gov (United States)

    William J. Matthews; A. Maria Miller-Lemke; Melvin L. Warren; Donna Cobb; Jeffery G. Stewart; Betty Crump; Frances P. Gelwick

    2004-01-01

    Abstract - Fish play diverse and important roles in stream ecosystems, but details about ecosystem effects are poorly known for many freshwater fish species. A requisite first step to understanding functional roles of individual species is information on their trophic ecology in the context of particular environmental settings. Stomach contents were...

  9. Ecosystem Fabrication (EcoFAB) Protocols for The Construction of Laboratory Ecosystems Designed to Study Plant-microbe Interactions.

    Science.gov (United States)

    Gao, Jian; Sasse, Joelle; Lewald, Kyle M; Zhalnina, Kateryna; Cornmesser, Lloyd T; Duncombe, Todd A; Yoshikuni, Yasuo; Vogel, John P; Firestone, Mary K; Northen, Trent R

    2018-04-10

    Beneficial plant-microbe interactions offer a sustainable biological solution with the potential to boost low-input food and bioenergy production. A better mechanistic understanding of these complex plant-microbe interactions will be crucial to improving plant production as well as performing basic ecological studies investigating plant-soil-microbe interactions. Here, a detailed description for ecosystem fabrication is presented, using widely available 3D printing technologies, to create controlled laboratory habitats (EcoFABs) for mechanistic studies of plant-microbe interactions within specific environmental conditions. Two sizes of EcoFABs are described that are suited for the investigation of microbial interactions with various plant species, including Arabidopsis thaliana, Brachypodium distachyon, and Panicum virgatum. These flow-through devices allow for controlled manipulation and sampling of root microbiomes, root chemistry as well as imaging of root morphology and microbial localization. This protocol includes the details for maintaining sterile conditions inside EcoFABs and mounting independent LED light systems onto EcoFABs. Detailed methods for addition of different forms of media, including soils, sand, and liquid growth media coupled to the characterization of these systems using imaging and metabolomics are described. Together, these systems enable dynamic and detailed investigation of plant and plant-microbial consortia including the manipulation of microbiome composition (including mutants), the monitoring of plant growth, root morphology, exudate composition, and microbial localization under controlled environmental conditions. We anticipate that these detailed protocols will serve as an important starting point for other researchers, ideally helping create standardized experimental systems for investigating plant-microbe interactions.

  10. Contemporary Ecological Interactions Improve Models of Past Trait Evolution.

    Science.gov (United States)

    Hutchinson, Matthew C; Gaiarsa, Marília P; Stouffer, Daniel B

    2018-02-20

    Despite the fact that natural selection underlies both traits and interactions, evolutionary models often neglect that ecological interactions may, and in many cases do, influence the evolution of traits. Here, we explore the interdependence of ecological interactions and functional traits in the pollination associations of hawkmoths and flowering plants. Specifically, we develop an adaptation of the Ornstein-Uhlenbeck model of trait evolution that allows us to study the influence of plant corolla depth and observed hawkmoth-plant interactions on the evolution of hawkmoth proboscis length. Across diverse modelling scenarios, we find that the inclusion of contemporary interactions can provide a better description of trait evolution than the null expectation. Moreover, we show that the pollination interactions provide more-likely models of hawkmoth trait evolution when interactions are considered at increasingly finescale groups of hawkmoths. Finally, we demonstrate how the results of best-fit modelling approaches can implicitly support the association between interactions and trait evolution that our method explicitly examines. In showing that contemporary interactions can provide insight into the historical evolution of hawkmoth proboscis length, we demonstrate the clear utility of incorporating additional ecological information to models designed to study past trait evolution.

  11. ECOLOGIC FEATURES OF WOOD ANATOMY OF Casearia sylvestris SW (SALICACEAE IN THREE BRAZILIAN ECOSYSTEMS

    Directory of Open Access Journals (Sweden)

    Graciene da Silva Mota

    2017-12-01

    Full Text Available Casearia sylvestris SW (Salicaceae is a highly adaptive perennial species that is found throughout Latin America and widely spread in Brazil. This work analyzed the ecological features of wood anatomy of C. sylvestris occurring in three ecosystem types: Cerrado, Gallery Forest (Northern of Minas Gerais and Mata Atlântica (Southern of Minas Gerais. Qualitative features were similar among plants in the three ecosystems, differing only in the distribution of pith flecks and neighboring tyloses that were more frequent in Cerrado and Gallery Forest. The quantitative results showed significant differences for several parameters, as well as variation between individuals of vegetation types of Northern and Southern of Minas Gerais. The correlation matrix of variables including quantitative anatomical characteristics, soil characteristics, height and diameter of the plants showed that plants were grouped by ecosystem type. Casearia sylvestris might adopt different survival strategies regarding safety and efficiency of water transport by wood anatomy ecological adaptation. The adaptive anatomical features to drought were mostly an decrease of vessel frequency and an increase of ray width and frequency.

  12. Ecological and Social Dimensions of Ecosystem Restoration in the Nordic Countries

    Directory of Open Access Journals (Sweden)

    Dagmar Hagen

    2013-12-01

    Full Text Available An international overview of the extent and type of ecological restoration can offer new perspectives for understanding, planning, and implementation. The Nordic countries, with a great range of natural conditions but historically similar social and political structures, provide an opportunity to compare restoration approaches and efforts across borders. The aim of this study was to explore variation in ecological restoration using the Nordic countries as an example. We used recent national assessments and expert evaluations of ecological restoration. Restoration efforts differed among countries: forest and peatland restoration was most common in Finland, freshwater restoration was most common in Sweden, restoration of natural heathlands and grasslands was most common in Iceland, restoration of natural and semi-cultural heathlands was most common in Norway, and restoration of cultural ecosystems, mainly abandoned agricultural land, was most common in Denmark. Ecological restoration currently does not occur on the Faroe Islands. Economic incentives influence ecological restoration and depend on laws and policies in each country. Our analyses suggest that habitat types determine the methods of ecological restoration, whereas socio-economic drivers are more important for the decisions concerning the timing and location of restoration. To improve the understanding, planning, and implementation of ecological restoration, we advocate increased cooperation and knowledge sharing across disciplines and among countries, both in the Nordic countries and internationally. An obvious advantage of such cooperation is that a wider range of experiences from different habitats and different socio-economic conditions becomes available and thus provides a more solid basis for developing practical solutions for restoration methods and policies.

  13. Complexity of human and ecosystem interactions in an agricultural landscape

    Science.gov (United States)

    Coupe, Richard H.; Barlow, Jeannie R.; Capel, Paul D.

    2012-01-01

    The complexity of human interaction in the commercial agricultural landscape and the resulting impacts on the ecosystem services of water quality and quantity is largely ignored by the current agricultural paradigm that maximizes crop production over other ecosystem services. Three examples at different spatial scales (local, regional, and global) are presented where human and ecosystem interactions in a commercial agricultural landscape adversely affect water quality and quantity in unintended ways in the Delta of northwestern Mississippi. In the first example, little to no regulation of groundwater use for irrigation has caused declines in groundwater levels resulting in loss of baseflow to streams and threatening future water supply. In the second example, federal policy which subsidizes corn for biofuel production has encouraged many producers to switch from cotton to corn, which requires more nutrients and water, counter to national efforts to reduce nutrient loads to the Gulf of Mexico and exacerbating groundwater level declines. The third example is the wholesale adoption of a system for weed control that relies on a single chemical, initially providing many benefits and ultimately leading to the widespread occurrence of glyphosate and its degradates in Delta streams and necessitating higher application rates of glyphosate as well as the use of other herbicides due to increasing weed resistance. Although these examples are specific to the Mississippi Delta, analogous situations exist throughout the world and point to the need for change in how we grow our food, fuel, and fiber, and manage our soil and water resources.

  14. The ecology, evolution, impacts and management of host-parasite interactions of marine molluscs.

    Science.gov (United States)

    Coen, Loren D; Bishop, Melanie J

    2015-10-01

    Molluscs are economically and ecologically important components of aquatic ecosystems. In addition to supporting valuable aquaculture and wild-harvest industries, their populations determine the structure of benthic communities, cycling of nutrients, serve as prey resources for higher trophic levels and, in some instances, stabilize shorelines and maintain water quality. This paper reviews existing knowledge of the ecology of host-parasite interactions involving marine molluscs, with a focus on gastropods and bivalves. It considers the ecological and evolutionary impacts of molluscan parasites on their hosts and vice versa, and on the communities and ecosystems in which they are a part, as well as disease management and its ecological impacts. An increasing number of case studies show that disease can have important effects on marine molluscs, their ecological interactions and ecosystem services, at spatial scales from centimeters to thousands of kilometers and timescales ranging from hours to years. In some instances the cascading indirect effects arising from parasitic infection of molluscs extend well beyond the temporal and spatial scales at which molluscs are affected by disease. In addition to the direct effects of molluscan disease, there can be large indirect impacts on marine environments resulting from strategies, such as introduction of non-native species and selective breeding for disease resistance, put in place to manage disease. Much of our understanding of impacts of molluscan diseases on the marine environment has been derived from just a handful of intensively studied marine parasite-host systems, namely gastropod-trematode, cockle-trematode, and oyster-protistan interactions. Understanding molluscan host-parasite dynamics is of growing importance because: (1) expanding aquaculture; (2) current and future climate change; (3) movement of non-native species; and (4) coastal development are modifying molluscan disease dynamics, ultimately leading to

  15. Insect-plant interactions: new pathways to a better comprehension of ecological communities in Neotropical savannas.

    Science.gov (United States)

    Del-Claro, Kleber; Torezan-Silingardi, Helena M

    2009-01-01

    The causal mechanisms shaping and structuring ecological communities are among the most important themes in ecology. The study of insect-plant interactions in trophic nets is pointed out as basic to improve our knowledge on this issue. The cerrado tropical savanna, although extremely diverse, distributed in more than 20% of the Brazilian territory and filled up with rich examples of multitrophic interactions, is underexplored in terms of biodiversity interaction. Here, this ecosystem is suggested as valuable to the study of insect-plant interactions whose understanding can throw a new light at the ecological communities' theory. Three distinct systems: extrafloral nectary plants or trophobiont herbivores and the associated ant fauna; floral herbivores-predators-pollinators; and plants-forest engineers and associated fauna, will serve as examples to illustrate promising new pathways in cerrado. The aim of this brief text is to instigate young researchers, mainly entomologists, to initiate more elaborated field work, including experimental manipulations in multitrophic systems, to explore in an interactive way the structure that maintain preserved viable communities in the Neotropical savanna.

  16. Agrochemical residue-biota interactions in soil and aquatic ecosystems

    International Nuclear Information System (INIS)

    1980-01-01

    Two FAO/IAEA coordinated research programmes are concerned with isotopic tracer-aided studies of agrochemical residue-biota interactions in soils and aquatic ecosystems. They currently involve 18 studies in 14 countries: Brazil, Canada, Egypt, F.R. Germany, Hungary, India, Indonesia, Iraq, Israel, Malaysia, Thailand, Turkey, USA and USSR. The aim was to develop, standardize and apply labelled substrate techniques for comparative assays of primary autotrophic and microheterotrophic production and decay, and complementary tracer techniques to determine the fate, persistence and bioconcentration of trace contaminants. Comparable data were studied concerning the current status of water bodies and likely changes due to contaminants. Soil capacity to decompose undesirable contaminants and residues, and to promote desirable transformations were studied. The techniques were also applied as a diagnostic and prognostic tool, with priority given to rice ecosystems

  17. Interactions among hydrogeomorphology, vegetation, and nutrient biogeochemistry in floodplain ecosystems

    Science.gov (United States)

    Noe, G.B.

    2013-01-01

    Hydrogeomorphic, vegetative, and biogeochemical processes interact in floodplains resulting in great complexity that provides opportunities to better understand linkages among physical and biological processes in ecosystems. Floodplains and their associated river systems are structured by four dimensional gradients of hydrogeomorphology: longitudinal, lateral, vertical, and temporal components. These four dimensions create dynamic hydrologic and geomorphologic mosaics that have a large imprint on the vegetation and nutrient biogeochemistry of floodplains. Plant physiology, population dynamics, community structure, and productivity are all very responsive to floodplain hydrogeomorphology. The strength of this relationship between vegetation and hydrogeomorphology is evident in the use of vegetation as an indicator of hydrogeomorphic processes. However, vegetation also influences hydrogeomorphology by modifying hydraulics and sediment entrainment and deposition that typically stabilize geomorphic patterns. Nitrogen and phosphorus biogeochemistry commonly influence plant productivity and community composition, although productivity is not limited by nutrient availability in all floodplains. Conversely, vegetation influences nutrient biogeochemistry through direct uptake and storage as well as production of organic matter that regulates microbial biogeochemical processes. The biogeochemistries of nitrogen and phosphorus cycling are very sensitive to spatial and temporal variation in hydrogeomorphology, in particular floodplain wetness and sedimentation. The least studied interaction is the direct effect of biogeochemistry on hydrogeomorphology, but the control of nutrient availability over organic matter decomposition and thus soil permeability and elevation is likely important. Biogeochemistry also has the more documented but indirect control of hydrogeomorphology through regulation of plant biomass. In summary, the defining characteristics of floodplain ecosystems

  18. Scaling Soil Microbe-Water Interactions from Pores to Ecosystems

    Science.gov (United States)

    Manzoni, S.; Katul, G. G.

    2014-12-01

    The spatial scales relevant to soil microbial activity are much finer than scales relevant to whole-ecosystem function and biogeochemical cycling. On the one hand, how to link such different scales and develop scale-aware biogeochemical and ecohydrological models remains a major challenge. On the other hand, resolving these linkages is becoming necessary for testing ecological hypotheses and resolving data-theory inconsistencies. Here, the relation between microbial respiration and soil moisture expressed in water potential is explored. Such relation mediates the water availability effects on ecosystem-level heterotrophic respiration and is of paramount importance for understanding CO2 emissions under increasingly variable rainfall regimes. Respiration has been shown to decline as the soil dries in a remarkably consistent way across climates and soil types (open triangles in Figure). Empirical models based on these respiration-moisture relations are routinely used in Earth System Models to predict moisture effects on ecosystem respiration. It has been hypothesized that this consistency in microbial respiration decline is due to breakage of water film continuity causing in turn solute diffusion limitations in dry conditions. However, this hypothesis appears to be at odds with what is known about soil hydraulic properties. Water film continuity estimated from soil water retention (SWR) measurements at the 'Darcy' scale breaks at far less negative water potential (micro-level relevant to microbial activity. Such downscaling resolves the inconsistency between respiration thresholds and hydrological thresholds. This result, together with observations of residual microbial activity well below -15 MPa (dashed back curve in Figure), lends support to the hypothesis that soil microbes are substrate-limited in dry conditions.

  19. Poor livestock keepers: ecosystem-poverty-health interactions.

    Science.gov (United States)

    Grace, Delia; Lindahl, Johanna; Wanyoike, Francis; Bett, Bernard; Randolph, Tom; Rich, Karl M

    2017-07-19

    Humans have never been healthier, wealthier or more numerous. Yet, present success may be at the cost of future prosperity and in some places, especially in sub-Saharan Africa, poverty persists. Livestock keepers, especially pastoralists, are over-represented among the poor. Poverty has been mainly attributed to a lack of access, whether to goods, education or enabling institutions. More recent insights suggest ecosystems may influence poverty and the self-reinforcing mechanisms that constitute poverty traps in more subtle ways. The plausibility of zoonoses as poverty traps is strengthened by landmark studies on disease burden in recent years. While in theory, endemic zoonoses are best controlled in the animal host, in practice, communities are often left to manage disease themselves, with the focus on treatment rather than prevention. We illustrate this with results from a survey on health costs in a pastoral ecosystem. Epidemic zoonoses are more likely to elicit official responses, but these can have unintended consequences that deepen poverty traps. In this context, a systems understanding of disease control can lead to more effective and pro-poor disease management. We illustrate this with an example of how a system dynamics model can help optimize responses to Rift Valley fever outbreaks in Kenya by giving decision makers real-time access to the costs of the delay in vaccinating. In conclusion, a broader, more ecological understanding of poverty and of the appropriate responses to the diseases of poverty can contribute to improved livelihoods for livestock keepers in Africa.This article is part of the themed issue 'One Health for a changing world: zoonoses, ecosystems and human well-being'. © 2017 The Authors.

  20. Bayesian Inference of Ecological Interactions from Spatial Data

    Directory of Open Access Journals (Sweden)

    Christopher R. Stephens

    2017-11-01

    Full Text Available The characterization and quantification of ecological interactions and the construction of species’ distributions and their associated ecological niches are of fundamental theoretical and practical importance. In this paper, we discuss a Bayesian inference framework, which, using spatial data, offers a general formalism within which ecological interactions may be characterized and quantified. Interactions are identified through deviations of the spatial distribution of co-occurrences of spatial variables relative to a benchmark for the non-interacting system and based on a statistical ensemble of spatial cells. The formalism allows for the integration of both biotic and abiotic factors of arbitrary resolution. We concentrate on the conceptual and mathematical underpinnings of the formalism, showing how, using the naive Bayes approximation, it can be used to not only compare and contrast the relative contribution from each variable, but also to construct species’ distributions and ecological niches based on an arbitrary variable type. We also show how non-linear interactions between distinct niche variables can be identified and the degree of confounding between variables accounted for.

  1. Assessing Freshwater Ecosystem Service Risk over Ecological, Socioeconomic, and Cultural Gradients: Problem Space Characterization and Methodology

    Science.gov (United States)

    Harmon, T. C.; Villamizar, S. R.; Conde, D.; Rusak, J.; Reid, B.; Astorga, A.; Perillo, G. M.; Piccolo, M. C.; Zilio, M.; London, S.; Velez, M.; Hoyos, N.; Escobar, J.

    2014-12-01

    Freshwater ecosystems and the services they provide are under increasing anthropogenic pressure at local (e.g., irrigation diversions, wastewater discharge) and global scales (e.g., climate change, global trading). The impact depends on an ecosystem's sensitivity, which is determined by its geophysical and ecological settings, and the population and activities in its surrounding watershed. Given the importance of ecosystem services, it is critical that we improve our ability to identify and understand changes in aquatic ecosystems, and translate them to risk of service loss. Furthermore, to inspire changes in human behavior, it is equally critical that we learn to communicate risk, and pose risk mitigation strategies, in a manner acceptable to a broad spectrum of stakeholders. Quantifying the nature and timing of the risk is difficult because (1) we often fail to understand the connection between anthropogenic pressures and the timing and extent of ecosystem changes; and (2) the concept of risk is inherently coupled to human perception, which generally differs with cultural and socio-economic conditions. In this study, we endeavor to assess aquatic ecosystem risks across an international array of six study sites. The challenge is to construct a methodology capable of capturing the marked biogeographical, socioeconomic, and cultural differences among the sites, which include: (1) Muskoka River watershed in humid continental Ontario, Canada; (2) Lower San Joaquin River, an impounded snow-fed river in semi-arid Central California; (3) Ciénaga Grande de Santa Marta, a tropical coastal lagoon in Colombia; (4) Senguer River basin in the semi-arid part of Argentina; (5) Laguna de Rocha watershed in humid subtropical Uruguay; and (6) Palomas Lake complex in oceanic Chilean Patagonia. Results will include a characterization of the experimental gradient over the six sites, an overview of the risk assessment methodology, and preliminary findings for several of the sites.

  2. Extrapolating ecological risks of ionizing radiation from individuals to populations to ecosystems

    International Nuclear Information System (INIS)

    Barnthouse, L.W.

    1997-01-01

    Approaches for protecting ecosystems from ionizing radiation are quite different from those used for protecting ecosystems from adverse effects of toxic chemicals. The methods used for chemicals are conceptually similar to those used to assess risks of chemicals to human health in that they focus on the protection of the most sensitive or most highly exposed individuals. The assumption is that if sensitive or maximally exposed species and life stages are protected, then ecosystems will be protected. Radiological protection standards, on the other hand, are explicitly premised on the assumption that organisms, populations and ecosystems all possess compensatory capabilities to allow them to survive in the face of unpredictable natural variation in their environments. These capabilities are assumed to persist in the face of at least some exposure to ionizing radiation. The prevailing approach to radiological protection was developed more than 30 years ago, at a time when the terms risk assessment and risk management were rarely used. The expert review approach used to derive radiological protection standards is widely perceived to be inconsistent with the open, participatory approach that prevails today for the regulation of toxic chemicals. The available data for environmental radionuclides vastly exceeds that available for any chemical. Therefore, given an understanding of dose-response relationships for radiation effects and exposures for individual organisms, it should be possible to develop methods for quantifying effects of radiation on populations. A tiered assessment scheme as well as available population models that could be used for the ecological risk assessment of radionuclides is presented. (author)

  3. Ecosystem services capacity across heterogeneous forest types: understanding the interactions and suggesting pathways for sustaining multiple ecosystem services.

    Science.gov (United States)

    Alamgir, Mohammed; Turton, Stephen M; Macgregor, Colin J; Pert, Petina L

    2016-10-01

    As ecosystem services supply from tropical forests is declining due to deforestation and forest degradation, much effort is essential to sustain ecosystem services supply from tropical forested landscapes, because tropical forests provide the largest flow of multiple ecosystem services among the terrestrial ecosystems. In order to sustain multiple ecosystem services, understanding ecosystem services capacity across heterogeneous forest types and identifying certain ecosystem services that could be managed to leverage positive effects across the wider bundle of ecosystem services are required. We sampled three forest types, tropical rainforests, sclerophyll forests, and rehabilitated plantation forests, over an area of 32,000m(2) from Wet Tropics bioregion, Australia, aiming to compare supply and evaluate interactions and patterns of eight ecosystem services (global climate regulation, air quality regulation, erosion regulation, nutrient regulation, cyclone protection, habitat provision, energy provision, and timber provision). On average, multiple ecosystem services were highest in the rainforests, lowest in sclerophyll forests, and intermediate in rehabilitated plantation forests. However, a wide variation was apparent among the plots across the three forest types. Global climate regulation service had a synergistic impact on the supply of multiple ecosystem services, while nutrient regulation service was found to have a trade-off impact. Considering multiple ecosystem services, most of the rehabilitated plantation forest plots shared the same ordination space with rainforest plots in the ordination analysis, indicating that rehabilitated plantation forests may supply certain ecosystem services nearly equivalent to rainforests. Two synergy groups and one trade-off group were identified. Apart from conserving rainforests and sclerophyll forests, our findings suggest two additional integrated pathways to sustain the supply of multiple ecosystem services from a

  4. Chemical ecology of the marine plankton.

    Science.gov (United States)

    Roy, Jessie S; Poulson-Ellestad, Kelsey L; Drew Sieg, R; Poulin, Remington X; Kubanek, Julia

    2013-10-11

    This review summarizes recent work in the chemical ecology of pelagic marine ecosystems. In order to provide a comprehensive overview of advances in the field over the period covered, we have organized this review by ecological interaction type beginning with intraspecific interactions, then interspecific interactions (including mutualism, parasitism, competition, and predation), and finally community- and ecosystem-wide interactions.

  5. Local ecological knowledge related with marine ecosystems in two coastal communities: El Valle and Sapzurro

    International Nuclear Information System (INIS)

    Correa, Sandra Liliana; Turbay, Sandra; Velez, Madelene

    2012-01-01

    The inhabitants of the Colombian coastal populations of El Valle, in the Pacific, and Sapzurro, in the Caribbean Darien, have ecological knowledge about coastal ecosystems that is a result of their constant relation with the sea, through fishing and navigation. The sea is a source of food and economical resources, but it is also the sphere where the male personality is forged. The accurate knowledge about mangrove, coral, coral reef, beaches and fishing grounds has been enriched through the dialog between local inhabitants and researchers in the conservation biology field. However, the tensions with researchers and environmental authorities still exist. The paper suggests that local ecological knowledge studies could be a starting point for maintaining a more horizontal dialogue between environmentalist and the populations with livelihoods derived of fishing.

  6. Functional genetics of intraspecific ecological interactions in Arabidopsis thaliana.

    Science.gov (United States)

    Wolf, Jason B; Mutic, Joshua J; Kover, Paula X

    2011-05-12

    Studying the genetic basis of traits involved in ecological interactions is a fundamental part of elucidating the connections between evolutionary and ecological processes. Such knowledge allows one to link genetic models of trait evolution with ecological models describing interactions within and between species. Previous work has shown that connections between genetic and ecological processes in Arabidopsis thaliana may be mediated by the fact that quantitative trait loci (QTL) with 'direct' effects on traits of individuals also have pleiotropic 'indirect' effects on traits expressed in neighbouring plants. Here, we further explore these connections by examining functional relationships between traits affected directly and indirectly by the same QTL. We develop a novel approach using structural equation models (SEMs) to determine whether observed pleiotropic effects result from traits directly affected by the QTL in focal individuals causing the changes in the neighbours' phenotypes. This hypothesis was assessed using SEMs to test whether focal plant phenotypes appear to mediate the connection between the focal plants' genotypes and the phenotypes of their neighbours, or alternatively, whether the connection between the focal plants' genotypes and the neighbours' phenotypes is mediated by unmeasured traits. We implement this analysis using a QTL of major effect that maps to the well-characterized flowering locus, FRIGIDA. The SEMs support the hypothesis that the pleiotropic indirect effects of this locus arise from size and developmental timing-related traits in focal plants affecting the expression of developmental traits in their neighbours. Our findings provide empirical insights into the genetics and nature of intraspecific ecological interactions. Our technique holds promise in directing future work into the genetic basis and functional relationship of traits mediating and responding to ecological interactions.

  7. Bioaerosols in the Earth system: Climate, health, and ecosystem interactions

    Energy Technology Data Exchange (ETDEWEB)

    Fröhlich-Nowoisky, Janine; Kampf, Christopher J.; Weber, Bettina; Huffman, J. Alex; Pöhlker, Christopher; Andreae, Meinrat O.; Lang-Yona, Naama; Burrows, Susannah M.; Gunthe, Sachin S.; Elbert, Wolfgang; Su, Hang; Hoor, Peter; Thines, Eckhard; Hoffmann, Thorsten; Després, Viviane R.; Pöschl, Ulrich

    2016-12-01

    Aerosols of biological origin play a vital role in the Earth system, particularly in the in-teractions between atmosphere, biosphere, climate, and public health. Airborne bacteria, fungal spores, pollen, and other bioparticles are essential for the reproduction and spread of organisms across various ecosystems, and they can cause or enhance human, animal, and plant diseases. Moreover, they can serve as nuclei for cloud droplets, ice crystals, and precipitation, thus influencing the hydrological cycle and climate. The actual formation, abundance, composition, and effects of biological aerosols and the atmospheric microbi-ome are, however, not yet well characterized and constitute a large gap in the scientific understanding of the interaction and co-evolution of life and climate in the Earth system. This review presents an overview of the state of bioaerosol research and highlights recent advances in terms of bioaerosol identification, characterization, transport, and transfor-mation processes, as well as their interactions with climate, health, and ecosystems, focus-ing on the role bioaerosols play in the Earth system.

  8. Molecular ecological insights into neotropical bird-tick interactions

    NARCIS (Netherlands)

    Miller, Matthew J.; Esser, Helen J.; Loaiza, Jose R.; Herre, Edward Allen; Aguilar, Celestino; Quintero, Diomedes; Alvarez, Eric; Bermingham, Eldredge

    2016-01-01

    In the tropics, ticks parasitize many classes of vertebrate hosts. However, because many tropical tick species are only identifiable in the adult stage, and these adults usually parasitize mammals, most attention on the ecology of tick-host interactions has focused on mammalian hosts. In

  9. Tick-Pathogen Ensembles: Do Molecular Interactions Lead Ecological Innovation?

    Czech Academy of Sciences Publication Activity Database

    Cabezas Cruz, Alejandro; Estrada-Peňa, A.; Rego, Ryan O. M.; de la Fuente, J.

    2017-01-01

    Roč. 7, 13 March (2017), č. článku 74. ISSN 2235-2988 Institutional support: RVO:60077344 Keywords : tick-pathogen interactions * transcriptional reprogramming * epigenetics * ecological adaptation * Anaplasma phagocytophilum Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Biochemistry and molecular biology Impact factor: 4.300, year: 2016

  10. MI-Sim: A MATLAB package for the numerical analysis of microbial ecological interactions.

    Directory of Open Access Journals (Sweden)

    Matthew J Wade

    Full Text Available Food-webs and other classes of ecological network motifs, are a means of describing feeding relationships between consumers and producers in an ecosystem. They have application across scales where they differ only in the underlying characteristics of the organisms and substrates describing the system. Mathematical modelling, using mechanistic approaches to describe the dynamic behaviour and properties of the system through sets of ordinary differential equations, has been used extensively in ecology. Models allow simulation of the dynamics of the various motifs and their numerical analysis provides a greater understanding of the interplay between the system components and their intrinsic properties. We have developed the MI-Sim software for use with MATLAB to allow a rigorous and rapid numerical analysis of several common ecological motifs. MI-Sim contains a series of the most commonly used motifs such as cooperation, competition and predation. It does not require detailed knowledge of mathematical analytical techniques and is offered as a single graphical user interface containing all input and output options. The tools available in the current version of MI-Sim include model simulation, steady-state existence and stability analysis, and basin of attraction analysis. The software includes seven ecological interaction motifs and seven growth function models. Unlike other system analysis tools, MI-Sim is designed as a simple and user-friendly tool specific to ecological population type models, allowing for rapid assessment of their dynamical and behavioural properties.

  11. MI-Sim: A MATLAB package for the numerical analysis of microbial ecological interactions.

    Science.gov (United States)

    Wade, Matthew J; Oakley, Jordan; Harbisher, Sophie; Parker, Nicholas G; Dolfing, Jan

    2017-01-01

    Food-webs and other classes of ecological network motifs, are a means of describing feeding relationships between consumers and producers in an ecosystem. They have application across scales where they differ only in the underlying characteristics of the organisms and substrates describing the system. Mathematical modelling, using mechanistic approaches to describe the dynamic behaviour and properties of the system through sets of ordinary differential equations, has been used extensively in ecology. Models allow simulation of the dynamics of the various motifs and their numerical analysis provides a greater understanding of the interplay between the system components and their intrinsic properties. We have developed the MI-Sim software for use with MATLAB to allow a rigorous and rapid numerical analysis of several common ecological motifs. MI-Sim contains a series of the most commonly used motifs such as cooperation, competition and predation. It does not require detailed knowledge of mathematical analytical techniques and is offered as a single graphical user interface containing all input and output options. The tools available in the current version of MI-Sim include model simulation, steady-state existence and stability analysis, and basin of attraction analysis. The software includes seven ecological interaction motifs and seven growth function models. Unlike other system analysis tools, MI-Sim is designed as a simple and user-friendly tool specific to ecological population type models, allowing for rapid assessment of their dynamical and behavioural properties.

  12. Offshore Fish Community: Ecological Interactions | Science ...

    Science.gov (United States)

    The offshore (>80 m) fish community of Lake Superior is made up of predominately native species. The most prominent species are deepwater sculpin, kiyi, cisco, siscowet lake trout, burbot, and the exotic sea lamprey. Bloater and shortjaw cisco are also found in the offshore zone. Bloater is abundant in the offshore zone but appears restricted to depths shallower than 150 m (Selgeby and Hoff 1996; Stockwell et al. 2010), although it occuppied greater depths several decades ago (Dryer 1966; Peck 1977). Shortjaw is relatively rare in the offshore zone (Hoff and Todd 2004; Gorman and Hoff 2009; Gorman and Todd 2007). Lake whitefish is also known to frequent bathymetric depths >100 m (Yule et al. 2008b). In this chapter, we develop a conceptual model of the offshore food web based on data collected during 2001-2005 and on inferences from species interactions known for the nearshore fish community. We then develop a framework for examination of energy and nutrient movements within the pelagic and benthic habitats of the offshore zone and across the offshore and nearshore zones. To document research results.

  13. Making the ecosystem approach operational-Can regime shifts in ecological- and governance systems facilitate the transition?

    DEFF Research Database (Denmark)

    Österblom, H.; Gårdmark, A.; Bergström, L.

    2010-01-01

    Effectively reducing cumulative impacts on marine ecosystems requires co-evolution between science, policy and practice. Here, long-term social–ecological changes in the Baltic Sea are described, illustrating how the process of making the ecosystem approach operational in a large marine ecosystem...... stimulating innovations and re-organizing governance structures at drainage basin level to the Baltic Sea catchment as a whole. Experimentation and innovation at local to the regional levels is critical for a transition to ecosystem-based management. Establishing science-based learning platforms at sub...

  14. Temporal scale dependent interactions between multiple environmental disturbances in microcosm ecosystems.

    Science.gov (United States)

    Garnier, Aurélie; Pennekamp, Frank; Lemoine, Mélissa; Petchey, Owen L

    2017-12-01

    Global environmental change has negative impacts on ecological systems, impacting the stable provision of functions, goods, and services. Whereas effects of individual environmental changes (e.g. temperature change or change in resource availability) are reasonably well understood, we lack information about if and how multiple changes interact. We examined interactions among four types of environmental disturbance (temperature, nutrient ratio, carbon enrichment, and light) in a fully factorial design using a microbial aquatic ecosystem and observed responses of dissolved oxygen saturation at three temporal scales (resistance, resilience, and return time). We tested whether multiple disturbances combine in a dominant, additive, or interactive fashion, and compared the predictability of dissolved oxygen across scales. Carbon enrichment and shading reduced oxygen concentration in the short term (i.e. resistance); although no other effects or interactions were statistically significant, resistance decreased as the number of disturbances increased. In the medium term, only enrichment accelerated recovery, but none of the other effects (including interactions) were significant. In the long term, enrichment and shading lengthened return times, and we found significant two-way synergistic interactions between disturbances. The best performing model (dominant, additive, or interactive) depended on the temporal scale of response. In the short term (i.e. for resistance), the dominance model predicted resistance of dissolved oxygen best, due to a large effect of carbon enrichment, whereas none of the models could predict the medium term (i.e. resilience). The long-term response was best predicted by models including interactions among disturbances. Our results indicate the importance of accounting for the temporal scale of responses when researching the effects of environmental disturbances on ecosystems. © 2017 The Authors. Global Change Biology Published by John Wiley

  15. Ecology

    International Nuclear Information System (INIS)

    Kalusche, D.

    1978-01-01

    The book turns to the freshment, the teacher, for preparation of ecological topics for lessons, but also to pupils of the secondary stage II, and the main course ecology. The book was knowingly held simple with the restriction to: the ecosystem and its abiotic basic functions, simple articles on population biology, bioceonotic balance ith the questions of niche formation and the life form types coherent with it, of the substance and energy household, the production biology and space-wise and time-wise differentations within an ecological system form the main points. A central role in the volume is given to the illustrations. Their variety is to show and deepen the coherences shown. (orig./HP) [de

  16. Shifting species interactions in terrestrial dryland ecosystems under altered water availability and climate change.

    Science.gov (United States)

    McCluney, Kevin E; Belnap, Jayne; Collins, Scott L; González, Angélica L; Hagen, Elizabeth M; Nathaniel Holland, J; Kotler, Burt P; Maestre, Fernando T; Smith, Stanley D; Wolf, Blair O

    2012-08-01

    Species interactions play key roles in linking the responses of populations, communities, and ecosystems to environmental change. For instance, species interactions are an important determinant of the complexity of changes in trophic biomass with variation in resources. Water resources are a major driver of terrestrial ecology and climate change is expected to greatly alter the distribution of this critical resource. While previous studies have documented strong effects of global environmental change on species interactions in general, responses can vary from region to region. Dryland ecosystems occupy more than one-third of the Earth's land mass, are greatly affected by changes in water availability, and are predicted to be hotspots of climate change. Thus, it is imperative to understand the effects of environmental change on these globally significant ecosystems. Here, we review studies of the responses of population-level plant-plant, plant-herbivore, and predator-prey interactions to changes in water availability in dryland environments in order to develop new hypotheses and predictions to guide future research. To help explain patterns of interaction outcomes, we developed a conceptual model that views interaction outcomes as shifting between (1) competition and facilitation (plant-plant), (2) herbivory, neutralism, or mutualism (plant-herbivore), or (3) neutralism and predation (predator-prey), as water availability crosses physiological, behavioural, or population-density thresholds. We link our conceptual model to hypothetical scenarios of current and future water availability to make testable predictions about the influence of changes in water availability on species interactions. We also examine potential implications of our conceptual model for the relative importance of top-down effects and the linearity of patterns of change in trophic biomass with changes in water availability. Finally, we highlight key research needs and some possible broader impacts

  17. Historical ecology provides new insights for ecosystem management: Eastern Baltic cod case study

    DEFF Research Database (Denmark)

    MacKenzie, Brian; Ojaveer, Henn; Eero, Margit

    2011-01-01

    A recent historical marine ecological case study (cod in the eastern Baltic Sea) is used to show how long-term data and knowledge of fluctuations can contribute to revisions of fishery management policy. The case study first developed new longer analytical time series of spawner biomass and recru......A recent historical marine ecological case study (cod in the eastern Baltic Sea) is used to show how long-term data and knowledge of fluctuations can contribute to revisions of fishery management policy. The case study first developed new longer analytical time series of spawner biomass...... catch data from the late 1500s to early 1600s also contributed new perspectives to cod population dynamics under alternative ecosystem forcings. These new perspectives have contributed, and will likely continue to contribute to new management policies (e.g., revision of fishery management reference...... points), which should lead to higher sustainability of the population and fishery yields, and improved overall ecosystem health. These perspectives will likely continue to provide baseline information as ICES and the EU develop new policies based on maximum sustainable yield concepts....

  18. Bioremediation in marine ecosystems: a computational study combining ecological modelling and flux balance analysis

    Directory of Open Access Journals (Sweden)

    Marianna eTaffi

    2014-09-01

    Full Text Available The pressure to search effective bioremediation methodologies for contaminated ecosystems has led to the large-scale identification of microbial species and metabolic degradation pathways. However, minor attention has been paid to the study of bioremediation in marine food webs and to the definition of integrated strategies for reducing bioaccumulation in species. We propose a novel computational framework for analysing the multiscale effects of bioremediation at the ecosystem level, based on coupling food web bioaccumulation models and metabolic models of degrading bacteria. The combination of techniques from synthetic biology and ecological network analysis allows the specification of arbitrary scenarios of contaminant removal and the evaluation of strategies based on natural or synthetic microbial strains.In this study, we derive a bioaccumulation model of polychlorinated biphenyls (PCBs in the Adriatic food web, and we extend a metabolic reconstruction of Pseudomonas putida KT2440 (iJN746 with the aerobic pathway of PCBs degradation. We assess the effectiveness of different bioremediation scenarios in reducing PCBs concentration in species and we study indices of species centrality to measure their importance in the contaminant diffusion via feeding links.The analysis of the Adriatic sea case study suggests that our framework could represent a practical tool in the design of effective remediation strategies, providing at the same time insights into the ecological role of microbial communities within food webs.

  19. The hidden ecological resource of andic soils in mountain ecosystems: evidence from Italy

    Directory of Open Access Journals (Sweden)

    F. Terribile

    2018-01-01

    Full Text Available Andic soils have unique morphological, physical, and chemical properties that induce both considerable soil fertility and great vulnerability to land degradation. Moreover, they are the most striking mineral soils in terms of large organic C storage and long C residence time. This is especially related to the presence of poorly crystalline clay minerals and metal–humus complexes. Recognition of andic soils is then very important.Here we attempt to show, through a combined analysis of 35 sampling points chosen in accordance to specific physical and vegetation rules, that some andic soils have an utmost ecological importance.More specifically, in Italian non-volcanic mountain ecosystems ( > 600 m a.s.l. combining low slope (< 21 % and highly active green biomass (high NDVI values and in agreement to recent findings, we found the widespread occurrence of andic soils having distinctive physical and hydrological properties including low bulk density and remarkably high water retention. Most importantly, we report a demonstration of the ability of these soils to affect ecosystem functions by analysing their influence on the timescale acceleration of photosynthesis estimated by NDVI measurements.Our results are hoped to be a starting point for better understanding of the ecological importance of andic soils and also possibly to better consider pedological information in C balance calculations.

  20. The hidden ecological resource of andic soils in mountain ecosystems: evidence from Italy

    Science.gov (United States)

    Terribile, Fabio; Iamarino, Michela; Langella, Giuliano; Manna, Piero; Mileti, Florindo Antonio; Vingiani, Simona; Basile, Angelo

    2018-01-01

    Andic soils have unique morphological, physical, and chemical properties that induce both considerable soil fertility and great vulnerability to land degradation. Moreover, they are the most striking mineral soils in terms of large organic C storage and long C residence time. This is especially related to the presence of poorly crystalline clay minerals and metal-humus complexes. Recognition of andic soils is then very important.Here we attempt to show, through a combined analysis of 35 sampling points chosen in accordance to specific physical and vegetation rules, that some andic soils have an utmost ecological importance.More specifically, in Italian non-volcanic mountain ecosystems ( > 600 m a.s.l.) combining low slope (highly active green biomass (high NDVI values) and in agreement to recent findings, we found the widespread occurrence of andic soils having distinctive physical and hydrological properties including low bulk density and remarkably high water retention. Most importantly, we report a demonstration of the ability of these soils to affect ecosystem functions by analysing their influence on the timescale acceleration of photosynthesis estimated by NDVI measurements.Our results are hoped to be a starting point for better understanding of the ecological importance of andic soils and also possibly to better consider pedological information in C balance calculations.

  1. Traits to Ecosystems: The Ecological Sustainability Challenge When Developing Future Energy Crops

    International Nuclear Information System (INIS)

    Weih, Martin; Hoeber, Stefanie; Beyer, Friderike; Fransson, Petra

    2014-01-01

    Today, we are undertaking great efforts to improve biomass production and quality traits of energy crops. Major motivation for developing those crops is based on environmental and ecological sustainability considerations, which however often are de-coupled from the trait-based crop improvement programs. It is now time to develop appropriate methods to link crop traits to production system characteristics set by the plant and the biotic communities influencing it; and to the ecosystem processes affecting ecological sustainability. The relevant ecosystem processes involve the net productivity in terms of biomass and energy yields, the depletion of energy-demanding resources (e.g., nitrogen, N), the carbon dynamics in soil and atmosphere, and the resilience and temporal stability of the production system. In a case study, we compared aspects of N use efficiency in various varieties of an annual (spring wheat) and perennial (Salix) energy crop grown under two nutrient regimes in Sweden. For example, we found considerable variation among crops, varieties, and nutrient regimes in the energy yield per plant-internal N (megajoule per gram per year), which would result in different N resource depletion per unit energy produced.

  2. Traits to Ecosystems: The Ecological Sustainability Challenge When Developing Future Energy Crops

    Energy Technology Data Exchange (ETDEWEB)

    Weih, Martin, E-mail: martin.weih@slu.se; Hoeber, Stefanie; Beyer, Friderike [Department of Crop Production Ecology, Swedish University of Agricultural Sciences, Uppsala (Sweden); Fransson, Petra [Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Sciences, Uppsala (Sweden)

    2014-05-22

    Today, we are undertaking great efforts to improve biomass production and quality traits of energy crops. Major motivation for developing those crops is based on environmental and ecological sustainability considerations, which however often are de-coupled from the trait-based crop improvement programs. It is now time to develop appropriate methods to link crop traits to production system characteristics set by the plant and the biotic communities influencing it; and to the ecosystem processes affecting ecological sustainability. The relevant ecosystem processes involve the net productivity in terms of biomass and energy yields, the depletion of energy-demanding resources (e.g., nitrogen, N), the carbon dynamics in soil and atmosphere, and the resilience and temporal stability of the production system. In a case study, we compared aspects of N use efficiency in various varieties of an annual (spring wheat) and perennial (Salix) energy crop grown under two nutrient regimes in Sweden. For example, we found considerable variation among crops, varieties, and nutrient regimes in the energy yield per plant-internal N (megajoule per gram per year), which would result in different N resource depletion per unit energy produced.

  3. Ecological interactions and the distribution, abundance, and diversity of sponges.

    Science.gov (United States)

    Wulff, Janie

    2012-01-01

    Although abiotic factors may be important first-order filters dictating which sponge species can thrive at a particular site, ecological interactions can play substantial roles influencing distribution and abundance, and thus diversity. Ecological interactions can modify the influences of abiotic factors both by further constraining distribution and abundance due to competitive or predatory interactions and by expanding habitat distribution or abundance due to beneficial interactions that ameliorate otherwise limiting circumstances. It is likely that the importance of ecological interactions has been greatly underestimated because they tend to only be revealed by experiments and time-series observations in the field. Experiments have revealed opportunistic predation to be a primary enforcer of sponge distribution boundaries that coincide with habitat boundaries in several systems. Within habitats, by contrast, dramatic effects of predators on sponge populations seem to occur primarily in cases of unusually high recruitment rates or unusually low mortality rates for the predators, which are often specialists on the sponge species affected. Competitive interactions have been demonstrated to diminish populations or exclude sponge species from a habitat in only a few cases. Cases in which competitive interactions have appeared obvious have often turned out to be neutral or even beneficial interactions when observed over time. Especially striking in this regard are sponge-sponge interactions in dense sponge-dominated communities, which may promote the continued coexistence of all participating species. Mutualistic symbioses of sponges with other animals, plants, or macroalgae have been demonstrated to increase abundance, habitat distribution, and diversity of all participants. Symbiotic microbes can enhance sponge distribution and abundance but also render their hosts more vulnerable to environmental changes. And while photosynthetic symbionts can boost growth and

  4. Interactions between Cryptosporidium parvum and the Intestinal Ecosystem

    KAUST Repository

    Douvropoulou, Olga

    2017-04-01

    Cryptosporidium parvum is an apicomplexan protozoan parasite commonly causing diarrhea, particularly in infants in developing countries. The research challenges faced in the development of therapies against Cryptosporidium slow down the process of drug discovery. However, advancement of knowledge towards the interactions of the intestinal ecosystem and the parasite could provide alternative approaches to tackle the disease. Under this perspective, the primary focus of this work was to study interactions between Cryptosporidium parvum and the intestinal ecosystem in a mouse model. Mice were treated with antibiotics with different activity spectra and the resulted perturbation of the native gut microbiota was identified by microbiome studies. In particular, 16S amplicon sequencing and Whole Genome Sequencing (WGS) were used to determine the bacterial composition and the genetic repertoire of the fecal microbial communities in the mouse gut. Following alteration of the microbial communities of mice by application of antibiotic treatment, Cryptosporidium parasites were propagated in mice with perturbed microbiota and the severity of the infection was quantified. This approach enabled the prediction of the functional capacity of the microbial communities in the mouse gut and led to the identification of bacterial taxa that positively or negatively correlate in abundance with Cryptosporidium proliferation.

  5. Recent advances in dental biofilm: impacts of microbial interactions on the biofilm ecology and pathogenesis

    Directory of Open Access Journals (Sweden)

    Yung-Hua Li

    2017-05-01

    Full Text Available The human oral cavity is a complex ecosystem harboring hundreds species of microbes that are largely living on the tooth surfaces as dental biofilms. Most microbes in dental biofilms promote oral health by stimulating the immune system or by preventing invasion of pathogens. Species diversity, high cell density and close proximity of cells are typical of life in dental biofilms, where microbes interact with each other and develop complex interactions that can be either competitive or cooperative. Competition between species is a well-recognized ecological force to drive microbial metabolism, species diversity and evolution. However, it was not until recently that microbial cooperative activities are also recognized to play important roles in microbial physiology and ecology. Importantly, these interactions profoundly affect the overall biomass, function, diversity and the pathogenesis in dental biofilms. It is now recognized that every human body contains a personalized oral microbiome that is essential to maintaining the oral health. Remarkably, the indigenous species in dental biofilms often maintain a relatively stable and harmless relationship with the host, despite regular exposure to environmental perturbations and the host defense factors. Such stability or homeostasis results from a dynamic balance of microbial-microbial and microbial-host interactions. Under certain circumstances, however, the homeostasis may breakdown, predisposing a site to diseases. In this review, we describe several examples of microbial interactions and their impacts on the homeostasis and pathogenesis of dental biofilms. We hope to encourage research on microbial interactions in the regulation of the homeostasis in biofilms.

  6. A Foray into Fungal Ecology: Understanding Fungi and Their Functions Across Ecosystems

    Science.gov (United States)

    Francis, N.; Dunkirk, N. C.; Peay, K.

    2015-12-01

    Despite their incredible diversity and importance to terrestrial ecosystems, fungi are not included in a standard high school science curriculum. This past summer, however, my work for the Stanford EARTH High School Internship program introduced me to fungal ecology through experiments involving culturing, genomics and root dissections. The two fungal experiments I worked on had very different foci, both searching for answers to broad ecological questions of fungal function and physiology. The first, a symbiosis experiment, sought to determine if the partners of the nutrient exchange between pine trees and their fungal symbionts could choose one another. The second experiment, a dung fungal succession project, compared the genetic sequencing results of fungal extractions from dung versus fungal cultures from dung. My part in the symbiosis experiment involved dissection, weighing and encapsulation of root tissue samples characterized based on the root thickness and presence of ectomycorrhizal fungi. The dung fungi succession project required that I not only learn how to culture various genera of dung fungi but also learn how to extract DNA and RNA for sequencing from the fungal tissue. Although I primarily worked with dung fungi cultures and thereby learned about their unique physiologies, I also learned about the different types of genetic sequencing since the project compared sequences of cultured fungi versus Next Generation sequencing of all fungi present within a dung pellet. Through working on distinct fungal projects that reassess how information about fungi is known within the field of fungal ecology, I learned not only about the two experiments I worked on but also many past related experiments and inquiries through reading scientific papers. Thanks to my foray into fungal research, I now know not only the broader significance of fungi in ecological research but also how to design and conduct ecological experiments.

  7. An ecological perspective on U.S. industrial poultry production: the role of anthropogenic ecosystems on the emergence of drug-resistant bacteria from agricultural environments.

    Science.gov (United States)

    Davis, Meghan F; Price, Lance B; Liu, Cindy Meng-Hsin; Silbergeld, Ellen K

    2011-06-01

    The industrialization of food animal production, specifically the widespread use of antimicrobials, not only increased pressure on microbial populations, but also changed the ecosystems in which antimicrobials and bacteria interact. In this review, we argue that industrial food animal production (IFAP) is appropriately defined as an anthropogenic ecosystem. This paper uses an ecosystem perspective to frame an examination of these changes in the context of U.S. broiler chicken production. This perspective emphasizes multiple modes by which IFAP has altered microbiomes and also suggests a means of generating hypotheses for understanding and predicting the ecological impacts of IFAP in terms of the resistome and the flow of resistance within and between microbiomes. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Ecological thresholds as a basis for defining management triggers for National Park Service vital signs: case studies for dryland ecosystems

    Science.gov (United States)

    Bowker, Matthew A.; Miller, Mark E.; Belote, R. Travis; Garman, Steven L.

    2013-01-01

    Threshold concepts are used in research and management of ecological systems to describe and interpret abrupt and persistent reorganization of ecosystem properties (Walker and Meyers, 2004; Groffman and others, 2006). Abrupt change, referred to as a threshold crossing, and the progression of reorganization can be triggered by one or more interactive disturbances such as land-use activities and climatic events (Paine and others, 1998). Threshold crossings occur when feedback mechanisms that typically absorb forces of change are replaced with those that promote development of alternative equilibria or states (Suding and others, 2004; Walker and Meyers, 2004; Briske and others, 2008). The alternative states that emerge from a threshold crossing vary and often exhibit reduced ecological integrity and value in terms of management goals relative to the original or reference system. Alternative stable states with some limited residual properties of the original system may develop along the progression after a crossing; an eventual outcome may be the complete loss of pre-threshold properties of the original ecosystem. Reverting to the more desirable reference state through ecological restoration becomes increasingly difficult and expensive along the progression gradient and may eventually become impossible. Ecological threshold concepts have been applied as a heuristic framework and to aid in the management of rangelands (Bestelmeyer, 2006; Briske and others, 2006, 2008), aquatic (Scheffer and others, 1993; Rapport and Whitford 1999), riparian (Stringham and others, 2001; Scott and others, 2005), and forested ecosystems (Allen and others, 2002; Digiovinazzo and others, 2010). These concepts are also topical in ecological restoration (Hobbs and Norton 1996; Whisenant 1999; Suding and others, 2004; King and Hobbs, 2006) and ecosystem sustainability (Herrick, 2000; Chapin and others, 1996; Davenport and others, 1998). Achieving conservation management goals requires the

  9. Interim report to the Northern Ecosystem Initiative from the Northern Ecological Monitoring and Assessment Network (EMAN-North)

    International Nuclear Information System (INIS)

    Wakelyn, L.; Eamer, J.

    2001-01-01

    The Northern Ecological Monitoring and Assessment Network (EMAN-North) has received funding for a proposal submitted to the Northern Ecosystems Initiative (NEI) in January 2001. EMAN-North is a network that coordinates ecological monitoring in northern Canada. Its geographic scope comprises 40 per cent of the geographic area of Canada, including Yukon, Northwest Territories and Nunavut, and an area near Churchill, Manitoba. Funding was awarded because the proposed EMAN-North project addressed the NEI priority of Monitoring Ecosystem Status and Trends, and Ecosystem Impacts of Climate Change. The project was also aimed at improving the network's capacity for long-term ecological monitoring, assessment and reporting. Several activities deal specifically with ecological impacts of climate change. This paper described the need and the context for ecological monitoring in northern Canada and defined a strategic direction for EMAN-North. The project will include many individuals involved in ecological monitoring in the north to deliver information on ecosystem changes to decision-makers and the public. refs., tabs., figs

  10. Interaction networks, ecological stability, and collective antibiotic tolerance in polymicrobial infections

    NARCIS (Netherlands)

    Vos, de Marjon G.J.; Zagorski, Marcin; McNally, Alan; Bollenbach, Tobias

    2017-01-01

    Polymicrobial infections constitute small ecosystems that accommodate several bacterial species. Commonly, these bacteria are investigated in isolation. However, it is unknown to what extent the isolates interact and whether their interactions alter bacterial growth and ecosystem resilience in

  11. Nitrogen deposition effects on Mediterranean-type ecosystems: An ecological assessment

    Energy Technology Data Exchange (ETDEWEB)

    Ochoa-Hueso, Raul, E-mail: raul.ochoa@ccma.csic.es [Department of Plant Physiology and Ecology, Centro de Ciencias Medioambientales, Consejo Superior de Investigaciones Cientificas, C/Serrano 115 Dpdo., 28006 Madrid (Spain); Allen, Edith B. [Department of Botany and Plant Sciences and Center for Conservation Biology, University of California, Riverside, CA 92521 (United States); Branquinho, Cristina; Cruz, Cristina; Dias, Teresa [Universidade de Lisboa, Faculdade de Ciencias, Centro de Biologia Ambiental, Campo Grande, Bloco C4, 1749-016 Lisboa (Portugal); Fenn, Mark E. [US Department of Agriculture (USDA) Forest Service, Pacific Southwest Research Station, 4955 Canyon Crest Drive, Riverside, CA 92507 (United States); Manrique, Esteban [Department of Plant Physiology and Ecology, Centro de Ciencias Medioambientales, Consejo Superior de Investigaciones Cientificas, C/Serrano 115 Dpdo., 28006 Madrid (Spain); Perez-Corona, M. Esther [Department of Ecology, Faculty of Biology, Universidad Complutense de Madrid, C/Jose Antonio Novais 2, 28040 Madrid (Spain); Sheppard, Lucy J. [Centre of Ecology and Hydrology, Bush Estate, Penicuik EH26 0QB (United Kingdom); Stock, William D. [Centre for Ecosystem Management, School of Natural Sciences, Edith Cowan University, 100 Joondalup Drive, Joondalup, Perth, WA 6027 (Australia)

    2011-10-15

    We review the ecological consequences of N deposition on the five Mediterranean regions of the world. Seasonality of precipitation and fires regulate the N cycle in these water-limited ecosystems, where dry N deposition dominates. Nitrogen accumulation in soils and on plant surfaces results in peaks of availability with the first winter rains. Decoupling between N flushes and plant demand promotes losses via leaching and gas emissions. Differences in P availability may control the response to N inputs and susceptibility to exotic plant invasion. Invasive grasses accumulate as fuel during the dry season, altering fire regimes. California and the Mediterranean Basin are the most threatened by N deposition; however, there is limited evidence for N deposition impacts outside of California. Consequently, more research is needed to determine critical loads for each region and vegetation type based on the most sensitive elements, such as changes in lichen species composition and N cycling. - Highlights: > N deposition impacts are understudied in Mediterranean ecosystems out of California. > Dry N deposition is dominant and N flushes are common after rainless periods. > Water availability and P fertility regulate ecosystem responses to N deposition. > Research is needed to determine critical loads for each region and vegetation type. - Nitrogen deposition threatens the Mediterranean regions of the world.

  12. Nitrogen deposition effects on Mediterranean-type ecosystems: An ecological assessment

    International Nuclear Information System (INIS)

    Ochoa-Hueso, Raul; Allen, Edith B.; Branquinho, Cristina; Cruz, Cristina; Dias, Teresa; Fenn, Mark E.; Manrique, Esteban; Perez-Corona, M. Esther; Sheppard, Lucy J.; Stock, William D.

    2011-01-01

    We review the ecological consequences of N deposition on the five Mediterranean regions of the world. Seasonality of precipitation and fires regulate the N cycle in these water-limited ecosystems, where dry N deposition dominates. Nitrogen accumulation in soils and on plant surfaces results in peaks of availability with the first winter rains. Decoupling between N flushes and plant demand promotes losses via leaching and gas emissions. Differences in P availability may control the response to N inputs and susceptibility to exotic plant invasion. Invasive grasses accumulate as fuel during the dry season, altering fire regimes. California and the Mediterranean Basin are the most threatened by N deposition; however, there is limited evidence for N deposition impacts outside of California. Consequently, more research is needed to determine critical loads for each region and vegetation type based on the most sensitive elements, such as changes in lichen species composition and N cycling. - Highlights: → N deposition impacts are understudied in Mediterranean ecosystems out of California. → Dry N deposition is dominant and N flushes are common after rainless periods. → Water availability and P fertility regulate ecosystem responses to N deposition. → Research is needed to determine critical loads for each region and vegetation type. - Nitrogen deposition threatens the Mediterranean regions of the world.

  13. Molecular Ecological Insights into Neotropical Bird-Tick Interactions.

    Science.gov (United States)

    Miller, Matthew J; Esser, Helen J; Loaiza, Jose R; Herre, Edward Allen; Aguilar, Celestino; Quintero, Diomedes; Alvarez, Eric; Bermingham, Eldredge

    2016-01-01

    In the tropics, ticks parasitize many classes of vertebrate hosts. However, because many tropical tick species are only identifiable in the adult stage, and these adults usually parasitize mammals, most attention on the ecology of tick-host interactions has focused on mammalian hosts. In contrast, immature Neotropical ticks are often found on wild birds, yet difficulties in identifying immatures hinder studies of birds' role in tropical tick ecology and tick-borne disease transmission. In Panama, we found immature ticks on 227 out of 3,498 individually-sampled birds representing 93 host species (24% of the bird species sampled, and 13% of the Panamanian land bird fauna). Tick parasitism rates did not vary with rainfall or temperature, but did vary significantly with several host ecological traits. Likewise, Neotropical-Nearctic migratory birds were significantly less likely to be infested than resident species. Using a molecular library developed from morphologically-identified adult ticks specifically for this study, we identified eleven tick species parasitizing birds, indicating that a substantial portion of the Panamanian avian species pool is parasitized by a diversity of tick species. Tick species that most commonly parasitized birds had the widest diversity of avian hosts, suggesting that immature tick species are opportunistic bird parasites. Although certain avian ecological traits are positively associated with parasitism, we found no evidence that individual tick species show specificity to particular avian host ecological traits. Finally, our data suggest that the four principal vectors of Rocky Mountain Spotted Fever in the Neotropics rarely, if ever, parasitize Panamanian birds. However, other tick species that harbor newly-discovered rickettsial parasites of unknown pathogenicity are frequently found on these birds. Given our discovery of broad interaction between Panamanian tick and avian biodiversity, future work on tick ecology and the dynamics of

  14. Molecular Ecological Insights into Neotropical Bird-Tick Interactions.

    Directory of Open Access Journals (Sweden)

    Matthew J Miller

    Full Text Available In the tropics, ticks parasitize many classes of vertebrate hosts. However, because many tropical tick species are only identifiable in the adult stage, and these adults usually parasitize mammals, most attention on the ecology of tick-host interactions has focused on mammalian hosts. In contrast, immature Neotropical ticks are often found on wild birds, yet difficulties in identifying immatures hinder studies of birds' role in tropical tick ecology and tick-borne disease transmission. In Panama, we found immature ticks on 227 out of 3,498 individually-sampled birds representing 93 host species (24% of the bird species sampled, and 13% of the Panamanian land bird fauna. Tick parasitism rates did not vary with rainfall or temperature, but did vary significantly with several host ecological traits. Likewise, Neotropical-Nearctic migratory birds were significantly less likely to be infested than resident species. Using a molecular library developed from morphologically-identified adult ticks specifically for this study, we identified eleven tick species parasitizing birds, indicating that a substantial portion of the Panamanian avian species pool is parasitized by a diversity of tick species. Tick species that most commonly parasitized birds had the widest diversity of avian hosts, suggesting that immature tick species are opportunistic bird parasites. Although certain avian ecological traits are positively associated with parasitism, we found no evidence that individual tick species show specificity to particular avian host ecological traits. Finally, our data suggest that the four principal vectors of Rocky Mountain Spotted Fever in the Neotropics rarely, if ever, parasitize Panamanian birds. However, other tick species that harbor newly-discovered rickettsial parasites of unknown pathogenicity are frequently found on these birds. Given our discovery of broad interaction between Panamanian tick and avian biodiversity, future work on tick ecology

  15. Intercalibrating classifications of ecological status: Europe's quest for common management objectives for aquatic ecosystems.

    Science.gov (United States)

    Birk, S; Willby, N J; Kelly, M G; Bonne, W; Borja, A; Poikane, S; van de Bund, W

    2013-06-01

    Halting and reversing the deterioration of aquatic ecosystems requires concerted action across state boundaries and administrative barriers. However, the achievement of common management objectives is jeopardised by different national quality targets and ambitions. The European Water Framework Directive requires that quality classifications are harmonised via an intercalibration exercise, ensuring a consistent level of ambition in the protection and restoration of surface water bodies across the Member States of the European Union. We outline the key principles of the intercalibration methodology, review the achievements of intercalibration and discuss its benefits and drawbacks. Less than half of the required intercalibration has been completed, mostly due to a lack of national assessment methods. The process has fostered a scientific debate on ecological classification with important implications for environmental management. Despite a significant level of statistical abstraction, intercalibration yielded a fundamental and unified vision of what constitutes good ecology across Europe, in principle ensuring greater parity in the funds invested to achieve good ecological status. Copyright © 2013 Elsevier B.V. All rights reserved.

  16. A review of ecological interactions between crayfish and fish, indigenous and introduced

    Directory of Open Access Journals (Sweden)

    Reynolds J.D.

    2011-05-01

    Full Text Available Crayfish (decapods and fish are both long-lived large members of freshwater communities, often functioning as keystone species. This paper reviews interactions between these, with emphasis on the European context. Native crayfish and fish are in ecological balance, which may involve mutual predation, competition and sometimes habitat disturbance. This balance is disrupted by range extensions and translocations of native fish or crayfish into exotic situations. Some fish and crayfish have been translocated globally, chiefly from North America to other continents. Non-indigenous crayfish species (NICS may impact on native fish, just as introduced fish impact on indigenous crayfish species (ICS. Competition between ICS and NICS may result in making the former susceptible to various mechanisms of interaction with fish, indigenous or introduced. In Europe, long-established NICS – signals, spiny-cheek and red swamp crayfish – may occur in greater densities than ICS; they are more tolerant and aggressive and show more interactions with fish. More recent introductions, still restricted in distribution, have not yet received enough study for their impacts to be assessed. Interactions between fish and crayfish in North and South America, Madagascar and Australasia are also explored. Mechanisms of interaction between fish and crayfish include mutual predation, competition for food and spatial resources, food-web alteration and habitat modification. Resultant changes in communities and ecosystems may be physical or biotal, and affect both ecosystem services and exploitation potential.

  17. Effects of Ocean Ecosystem on Marine Aerosol-Cloud Interaction

    Directory of Open Access Journals (Sweden)

    Nicholas Meskhidze

    2010-01-01

    Full Text Available Using satellite data for the surface ocean, aerosol optical depth (AOD, and cloud microphysical parameters, we show that statistically significant positive correlations exist between ocean ecosystem productivity, the abundance of submicron aerosols, and cloud microphysical properties over different parts of the remote oceans. The correlation coefficient for remotely sensed surface chlorophyll a concentration ([Chl-a] and liquid cloud effective radii over productive areas of the oceans varies between −0.2 and −0.6. Special attention is given to identifying (and addressing problems from correlation analysis used in the previous studies that can lead to erroneous conclusions. A new approach (using the difference between retrieved AOD and predicted sea salt aerosol optical depth, AODdiff is developed to explore causal links between ocean physical and biological systems and the abundance of cloud condensation nuclei (CCN in the remote marine atmosphere. We have found that over multiple time periods, 550 nm AODdiff (sensitive to accumulation mode aerosol, which is the prime contributor to CCN correlates well with [Chl-a] over the productive waters of the Southern Ocean. Since [Chl-a] can be used as a proxy of ocean biological productivity, our analysis demonstrates the role of ocean ecology in contributing CCN, thus shaping the microphysical properties of low-level marine clouds.

  18. Species-Specific Effects on Ecosystem Functioning Can Be Altered by Interspecific Interactions.

    Science.gov (United States)

    Clare, David S; Spencer, Matthew; Robinson, Leonie A; Frid, Christopher L J

    2016-01-01

    Biological assemblages are constantly undergoing change, with species being introduced, extirpated and experiencing shifts in their densities. Theory and experimentation suggest that the impacts of such change on ecosystem functioning should be predictable based on the biological traits of the species involved. However, interspecific interactions could alter how species affect functioning, with the strength and sign of interactions potentially depending on environmental context (e.g. homogenous vs. heterogeneous conditions) and the function considered. Here, we assessed how concurrent changes to the densities of two common marine benthic invertebrates, Corophium volutator and Hediste diversicolor, affected the ecological functions of organic matter consumption and benthic-pelagic nutrient flux. Complementary experiments were conducted within homogenous laboratory microcosms and naturally heterogeneous field plots. When the densities of the species were increased within microcosms, interspecific interactions enhanced effects on organic matter consumption and reduced effects on nutrient flux. Trait-based predictions of how each species would affect functioning were only consistently supported when the density of the other species was low. In field plots, increasing the density of either species had a positive effect on organic matter consumption (with no significant interspecific interactions) but no effect on nutrient flux. Our results indicate that species-specific effects on ecosystem functioning can be altered by interspecific interactions, which can be either facilitative (positive) or antagonistic (negative) depending on the function considered. The impacts of biodiversity change may therefore not be predictable based solely on the biological traits of the species involved. Possible explanations for why interactions were detected in microcosms but not in the field are discussed.

  19. Species-Specific Effects on Ecosystem Functioning Can Be Altered by Interspecific Interactions.

    Directory of Open Access Journals (Sweden)

    David S Clare

    Full Text Available Biological assemblages are constantly undergoing change, with species being introduced, extirpated and experiencing shifts in their densities. Theory and experimentation suggest that the impacts of such change on ecosystem functioning should be predictable based on the biological traits of the species involved. However, interspecific interactions could alter how species affect functioning, with the strength and sign of interactions potentially depending on environmental context (e.g. homogenous vs. heterogeneous conditions and the function considered. Here, we assessed how concurrent changes to the densities of two common marine benthic invertebrates, Corophium volutator and Hediste diversicolor, affected the ecological functions of organic matter consumption and benthic-pelagic nutrient flux. Complementary experiments were conducted within homogenous laboratory microcosms and naturally heterogeneous field plots. When the densities of the species were increased within microcosms, interspecific interactions enhanced effects on organic matter consumption and reduced effects on nutrient flux. Trait-based predictions of how each species would affect functioning were only consistently supported when the density of the other species was low. In field plots, increasing the density of either species had a positive effect on organic matter consumption (with no significant interspecific interactions but no effect on nutrient flux. Our results indicate that species-specific effects on ecosystem functioning can be altered by interspecific interactions, which can be either facilitative (positive or antagonistic (negative depending on the function considered. The impacts of biodiversity change may therefore not be predictable based solely on the biological traits of the species involved. Possible explanations for why interactions were detected in microcosms but not in the field are discussed.

  20. DEPENDENCE OF GRASS COVER TAXONOMIC AND ECOLOGICAL STRUCTURE ON THE ANTHROPOGENIC IMPACT IN FOREST ECOSYSTEMS

    Directory of Open Access Journals (Sweden)

    N. V. Miroshnik

    2016-01-01

    revealed the domination of plant species that are tolerant to transformed forest conditions due to drastic anthropogenic changes of ecological regimes in Chygyryn's Bor. Key words: grass cover, Chigirin's Bor, anthropogenic impact, forest ecosystem, industrial transformation and degradation of grass cover.

  1. Using Flow-Ecology Relationships to Evaluate Ecosystem Service Trade-Offs and Complementarities in the Nation's Largest River Swamp

    Science.gov (United States)

    Kozak, Justin P.; Bennett, Micah G.; Hayden-Lesmeister, Anne; Fritz, Kelley A.; Nickolotsky, Aaron

    2015-06-01

    Large river systems are inextricably linked with social systems; consequently, management decisions must be made within a given ecological, social, and political framework that often defies objective, technical resolution. Understanding flow-ecology relationships in rivers is necessary to assess potential impacts of management decisions, but translating complex flow-ecology relationships into stakeholder-relevant information remains a struggle. The concept of ecosystem services provides a bridge between flow-ecology relationships and stakeholder-relevant data. Flow-ecology relationships were used to explore complementary and trade-off relationships among 12 ecosystem services and related variables in the Atchafalaya River Basin, Louisiana. Results from Indicators of Hydrologic Alteration were reduced to four management-relevant hydrologic variables using principal components analysis. Multiple regression was used to determine flow-ecology relationships and Pearson correlation coefficients, along with regression results, were used to determine complementary and trade-off relationships among ecosystem services and related variables that were induced by flow. Seven ecosystem service variables had significant flow-ecology relationships for at least one hydrologic variable ( R 2 = 0.19-0.64). River transportation and blue crab ( Callinectes sapidus) landings exhibited a complementary relationship mediated by flow; whereas transportation and crawfish landings, crawfish landings and crappie ( Pomoxis spp.) abundance, and blue crab landings and blue catfish ( Ictalurus furcatus) abundance exhibited trade-off relationships. Other trade-off and complementary relationships among ecosystem services and related variables, however, were not related to flow. These results give insight into potential conflicts among stakeholders, can reduce the dimensions of management decisions, and provide initial hypotheses for experimental flow modifications.

  2. Using Flow-Ecology Relationships to Evaluate Ecosystem Service Trade-Offs and Complementarities in the Nation's Largest River Swamp.

    Science.gov (United States)

    Kozak, Justin P; Bennett, Micah G; Hayden-Lesmeister, Anne; Fritz, Kelley A; Nickolotsky, Aaron

    2015-06-01

    Large river systems are inextricably linked with social systems; consequently, management decisions must be made within a given ecological, social, and political framework that often defies objective, technical resolution. Understanding flow-ecology relationships in rivers is necessary to assess potential impacts of management decisions, but translating complex flow-ecology relationships into stakeholder-relevant information remains a struggle. The concept of ecosystem services provides a bridge between flow-ecology relationships and stakeholder-relevant data. Flow-ecology relationships were used to explore complementary and trade-off relationships among 12 ecosystem services and related variables in the Atchafalaya River Basin, Louisiana. Results from Indicators of Hydrologic Alteration were reduced to four management-relevant hydrologic variables using principal components analysis. Multiple regression was used to determine flow-ecology relationships and Pearson correlation coefficients, along with regression results, were used to determine complementary and trade-off relationships among ecosystem services and related variables that were induced by flow. Seven ecosystem service variables had significant flow-ecology relationships for at least one hydrologic variable (R (2) = 0.19-0.64). River transportation and blue crab (Callinectes sapidus) landings exhibited a complementary relationship mediated by flow; whereas transportation and crawfish landings, crawfish landings and crappie (Pomoxis spp.) abundance, and blue crab landings and blue catfish (Ictalurus furcatus) abundance exhibited trade-off relationships. Other trade-off and complementary relationships among ecosystem services and related variables, however, were not related to flow. These results give insight into potential conflicts among stakeholders, can reduce the dimensions of management decisions, and provide initial hypotheses for experimental flow modifications.

  3. A tale of two phylogenies: comparative analyses of ecological interactions.

    Science.gov (United States)

    Hadfield, Jarrod D; Krasnov, Boris R; Poulin, Robert; Nakagawa, Shinichi

    2014-02-01

    The evolution of traits involved in ecological interactions such as predator-prey, host-parasite, and plant-pollinator interactions, are likely to be shaped by the phylogenetic history of both parties. We develop generalized linear mixed-effects models (GLMM) that estimate the effect of both parties' phylogenetic history on trait evolution, both in isolation but also in terms of how the two histories interact. Using data on the incidence and abundance of 206 flea species on 121 mammal species, we illustrate our method and compare it to previously used methods for detecting host-parasite coevolution. At large spatial scales we find that the phylogenetic interaction effect was substantial, indicating that related parasite species were more likely to be found on related host species. At smaller spatial scales, and when sampling effort was not controlled for, phylogenetic effects on the number and types of parasite species harbored by hosts were found to dominate. We go on to show that in situations where these additional phylogenetic effects exist, then previous methods have very high Type I error rates when testing for the phylogenetic interaction. Our GLMM method represents a robust and reliable approach to quantify the phylogenetic effects of traits determined by, or defined by, ecological interactions and has the advantage that it can easily be extended and interpreted in a broader context than existing permutation tests.

  4. Coupled hydrological, ecological, decision and economic models for monetary valuation of riparian ecosystem services

    Science.gov (United States)

    Goodrich, D. C.; Brookshire, D.; Broadbent, C.; Dixon, M. D.; Brand, L. A.; Thacher, J.; Benedict, K. K.; Lansey, K. E.; Stromberg, J. C.; Stewart, S.; McIntosh, M.

    2011-12-01

    Water is a critical component for sustaining both natural and human systems. Yet the value of water for sustaining ecosystem services is not well quantified in monetary terms. Ideally decisions involving water resource management would include an apples-to-apples comparison of the costs and benefits in dollars of both market and non-market goods and services - human and ecosystem. To quantify the value of non-market ecosystem services, scientifically defensible relationships must be developed that link the effect of a decision (e.g. human growth) to the change in ecosystem attributes from current conditions. It is this linkage that requires the "poly-disciplinary" coupling of knowledge and models from the behavioral, physical, and ecological sciences. In our experience another key component of making this successful linkage is development of a strong poly-disciplinary scientific team that can readily communicate complex disciplinary knowledge to non-specialists outside their own discipline. The time to build such a team that communicates well and has a strong sense of trust should not be underestimated. The research described in the presentation incorporated hydrologic, vegetation, avian, economic, and decision models into an integrated framework to determine the value of changes in ecological systems that result from changes in human water use. We developed a hydro-bio-economic framework for the San Pedro River Region in Arizona that considers groundwater, stream flow, and riparian vegetation, as well as abundance, diversity, and distribution of birds. In addition, we developed a similar framework for the Middle Rio Grande of New Mexico. There are six research components for this project: (1) decision support and scenario specification, (2) regional groundwater model, (3) the riparian vegetation model, (4) the avian model, (5) methods for displaying the information gradients in the valuation survey instruments (Choice Modeling and Contingent Valuation), and (6

  5. Frontiers of torenia research: innovative ornamental traits and study of ecological interaction networks through genetic engineering

    Science.gov (United States)

    2013-01-01

    Advances in research in the past few years on the ornamental plant torenia (Torenia spps.) have made it notable as a model plant on the frontier of genetic engineering aimed at studying ornamental characteristics and pest control in horticultural ecosystems. The remarkable advantage of torenia over other ornamental plant species is the availability of an easy and high-efficiency transformation system for it. Unfortunately, most of the current torenia research is still not very widespread, because this species has not become prominent as an alternative to other successful model plants such as Arabidopsis, snapdragon and petunia. However, nowadays, a more global view using not only a few selected models but also several additional species are required for creating innovative ornamental traits and studying horticultural ecosystems. We therefore introduce and discuss recent research on torenia, the family Scrophulariaceae, for secondary metabolite bioengineering, in which global insights into horticulture, agriculture and ecology have been advanced. Floral traits, in torenia particularly floral color, have been extensively studied by manipulating the flavonoid biosynthetic pathways in flower organs. Plant aroma, including volatile terpenoids, has also been genetically modulated in order to understand the complicated nature of multi-trophic interactions that affect the behavior of predators and pollinators in the ecosystem. Torenia would accordingly be of great use for investigating both the variation in ornamental plants and the infochemical-mediated interactions with arthropods. PMID:23803155

  6. Assessing the grass Schizachyrium gracile for capacity to ecologically restore the polluted soils of ecosystems in a bauxite mining area

    Energy Technology Data Exchange (ETDEWEB)

    Pastor, J.; Alexis, S.; Hernandez, A. J.

    2009-07-01

    Abandoned bauxite mines in the tropical forest of the Dominican Republics only biosphere reserve are leaving behind extensive areas and landfills, whose negative impacts need restoring because of the ecological interest of the sites they occupy. Given that any realistic recovery program should be based on knowledge of the ecological succession, in this report we present the results derived from the study of two populations of a pioneer species of these ecosystems. (Author)

  7. Assessing the grass Schizachyrium gracile for capacity to ecologically restore the polluted soils of ecosystems in a bauxite mining area

    International Nuclear Information System (INIS)

    Pastor, J.; Alexis, S.; Hernandez, A. J.

    2009-01-01

    Abandoned bauxite mines in the tropical forest of the Dominican Republics only biosphere reserve are leaving behind extensive areas and landfills, whose negative impacts need restoring because of the ecological interest of the sites they occupy. Given that any realistic recovery program should be based on knowledge of the ecological succession, in this report we present the results derived from the study of two populations of a pioneer species of these ecosystems. (Author)

  8. Baseflow vs floods: Linking geomorphology and ecology by blurring disciplinary and ecosystem boundaries

    Science.gov (United States)

    Doyle, M. W.; Stanley, E. H.; Small, M.

    2011-12-01

    emerge from drawing in geomorphology or hydrology into ecology, or vice versa. We suggest two approaches to continuing to bridge disciplines and potentially push forward river science. First, by looking for concepts formative in one discipline for which there are no analogous counter-parts in the other discipline, we may be able to re-analyze existing data in ways that are more conducive to interpretation by other disciplines. Converting nutrient spiraling metrics into effective discharge metrics is one such example. Another example worth exploring is Schumm and Licthy's classic time, space, and causality, but applied to stream ecology or biogeochemistry. A second approach is to blur the boundaries of ecosystems studied, either temporally or spatially. For example, expanding the spatial scale beyond the 'obvious' boundary of the streambed led to the discovery of the hyporheic zone; expanding traditional ecology study reaches led to the spate of research on tributary junctions network geometry. We suspect that there are similar opportunities for new discoveries or concepts through the intentional blurring of oft-used boundaries to stream studies.

  9. Plant-aphid interactions: molecular and ecological perspectives.

    Science.gov (United States)

    Goggin, Fiona L

    2007-08-01

    Many aphids are major agricultural pests because of their unparalleled reproductive capacity and their ability to manipulate host plant physiology. Aphid population growth and its impact on plant fitness are strongly influenced by interactions with other organisms, including plant pathogens, endophytes, aphid endosymbionts, predators, parasitoids, ants, and other herbivores. Numerous molecular and genomic resources have recently been developed to identify sources of aphid resistance in plants, as well as potentially novel targets for control in aphids. Moreover, the same model systems that are used to explore direct molecular interactions between plants and aphids can be utilized to study the ecological context in which they occur.

  10. Quorum sensing is a language of chemical signals and plays an ecological role in algal-bacterial interactions.

    Science.gov (United States)

    Zhou, Jin; Lyu, Yihua; Richlen, Mindy; Anderson, Donald M; Cai, Zhonghua

    2016-01-01

    Algae are ubiquitous in the marine environment, and the ways in which they interact with bacteria are of particular interest in marine ecology field. The interactions between primary producers and bacteria impact the physiology of both partners, alter the chemistry of their environment, and shape microbial diversity. Although algal-bacterial interactions are well known and studied, information regarding the chemical-ecological role of this relationship remains limited, particularly with respect to quorum sensing (QS), which is a system of stimuli and response correlated to population density. In the microbial biosphere, QS is pivotal in driving community structure and regulating behavioral ecology, including biofilm formation, virulence, antibiotic resistance, swarming motility, and secondary metabolite production. Many marine habitats, such as the phycosphere, harbour diverse populations of microorganisms and various signal languages (such as QS-based autoinducers). QS-mediated interactions widely influence algal-bacterial symbiotic relationships, which in turn determine community organization, population structure, and ecosystem functioning. Understanding infochemicals-mediated ecological processes may shed light on the symbiotic interactions between algae host and associated microbes. In this review, we summarize current achievements about how QS modulates microbial behavior, affects symbiotic relationships, and regulates phytoplankton chemical ecological processes. Additionally, we present an overview of QS-modulated co-evolutionary relationships between algae and bacterioplankton, and consider the potential applications and future perspectives of QS.

  11. Re-establishing an ecological discourse in the policy debate over how to value ecosystems and biodiversity.

    Science.gov (United States)

    Spash, Clive L; Aslaksen, Iulie

    2015-08-15

    In this paper we explore the discourses of ecology, environmental economics, new environmental pragmatism and social ecological economics as they relate to the value of ecosystems and biodiversity. Conceptualizing biodiversity and ecosystems as goods and services that can be represented by monetary values in policy processes is an economic discourse being increasingly championed by ecologists and conservation biologists. The latter promote a new environmental pragmatism internationally as hardwiring biodiversity and ecosystems services into finance. The approach adopts a narrow instrumentalism, denies value pluralism and incommensurability, and downplays the role of scientific knowledge. Re-establishing an ecological discourse in biodiversity policy implies a crucial role for biophysical indicators as independent policy targets, exemplified in this paper by the Nature Index for Norway. Yet, there is a recognisable need to go beyond a traditional ecological approach to one recognising the interconnections of social, ecological and economic problems. This requires reviving and relating to a range of alternative ecologically informed discourses, including an ecofeminist perspective, in order to transform the increasingly dominant and destructive relationship of humans separated from and domineering over Nature. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Foraging ecology and spatial behavior of the red fox (Vulpes vulpes) in a wet grassland ecosystem

    DEFF Research Database (Denmark)

    Meisner, Katrine; Sunde, Peter; Clausen, Kevin Kuhlmann

    2014-01-01

    We investigated diet composition, habitat selection and spatial behaviour of the red fox (Vulpes vulpes) in relation to the availability of wader nests in a coastal polder area in southwest Denmark. The predatory role of the red fox in wet grassland ecosystems has profound implications...... for conservation status of declining populations of grassland breeding waders. However, few studies have focussed on the foraging ecology and behaviour of the red fox in these landscapes. Faecal analyses revealed that fox diet consisted of birds (43 % of prey remains / 32 % of biomass), rodents (39 % / 21...... %), sheep (mainly as carrion, 14 % / 41 %) and lagomorphs (4 % / 7 %). Charadriiformes (including waders) comprised 3–12 % of prey remains throughout the year. Telemetry data and spotlight counts indicated that foxes did not select areas with high densities of breeding waders, suggesting that foxes did...

  13. The evolutionary ecology of cytonuclear interactions in angiosperms.

    Science.gov (United States)

    Caruso, Christina M; Case, Andrea L; Bailey, Maia F

    2012-11-01

    Interactions between cytoplasmic and nuclear genomes have significant evolutionary consequences. In angiosperms, the most common cytonuclear interaction is between mitochondrial genes that disrupt pollen production (cytoplasmic male sterility, CMS) and nuclear genes that restore it (nuclear male fertility restorers, Rf). The outcome of CMS/Rf interactions can depend on whether Rf alleles have negative pleiotropic effects on fitness. Although these fitness costs are often considered to be independent of the ecological context, we argue that the effects of Rf alleles on fitness should be context dependent. Thus, measuring the cost of restoration across a range of environments could help explain geographic and phylogenetic variation in the distribution of Rf alleles and the outcome of CMS/Rf interactions. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Seeing Cooperation or Competition: Ecological Interactions in Cultural Perspectives.

    Science.gov (United States)

    Ojalehto, Bethany L; Medin, Douglas L; Horton, William S; Garcia, Salino G; Kays, Estefano G

    2015-10-01

    Do cultural models facilitate particular ways of perceiving interactions in nature? We explore variability in folkecological principles of reasoning about interspecies interactions (specifically, competitive or cooperative). In two studies, Indigenous Panamanian Ngöbe and U.S. participants interpreted an illustrated, wordless nonfiction book about the hunting relationship between a coyote and badger. Across both studies, the majority of Ngöbe interpreted the hunting relationship as cooperative and the majority of U.S. participants as competitive. Study 2 showed that this pattern may reflect different beliefs about, and perhaps different awareness of, plausible interspecies interactions. Further probes suggest that these models of ecological interaction correlate with recognition of social agency (e.g., communication, morality) in nonhuman animals. We interpret our results in terms of cultural models of nature and nonhuman agency. Copyright © 2015 Cognitive Science Society, Inc.

  15. Genetic Allee effects and their interaction with ecological Allee effects.

    Science.gov (United States)

    Wittmann, Meike J; Stuis, Hanna; Metzler, Dirk

    2018-01-01

    It is now widely accepted that genetic processes such as inbreeding depression and loss of genetic variation can increase the extinction risk of small populations. However, it is generally unclear whether extinction risk from genetic causes gradually increases with decreasing population size or whether there is a sharp transition around a specific threshold population size. In the ecological literature, such threshold phenomena are called 'strong Allee effects' and they can arise for example from mate limitation in small populations. In this study, we aim to (i) develop a meaningful notion of a 'strong genetic Allee effect', (ii) explore whether and under what conditions such an effect can arise from inbreeding depression due to recessive deleterious mutations, and (iii) quantify the interaction of potential genetic Allee effects with the well-known mate-finding Allee effect. We define a strong genetic Allee effect as a genetic process that causes a population's survival probability to be a sigmoid function of its initial size. The inflection point of this function defines the critical population size. To characterize survival-probability curves, we develop and analyse simple stochastic models for the ecology and genetics of small populations. Our results indicate that inbreeding depression can indeed cause a strong genetic Allee effect, but only if individuals carry sufficiently many deleterious mutations (lethal equivalents). Populations suffering from a genetic Allee effect often first grow, then decline as inbreeding depression sets in and then potentially recover as deleterious mutations are purged. Critical population sizes of ecological and genetic Allee effects appear to be often additive, but even superadditive interactions are possible. Many published estimates for the number of lethal equivalents in birds and mammals fall in the parameter range where strong genetic Allee effects are expected. Unfortunately, extinction risk due to genetic Allee effects

  16. Spatial interactions among ecosystem services in an urbanizing agricultural watershed.

    Science.gov (United States)

    Qiu, Jiangxiao; Turner, Monica G

    2013-07-16

    Understanding spatial distributions, synergies, and tradeoffs of multiple ecosystem services (benefits people derive from ecosystems) remains challenging. We analyzed the supply of 10 ecosystem services for 2006 across a large urbanizing agricultural watershed in the Upper Midwest of the United States, and asked the following: (i) Where are areas of high and low supply of individual ecosystem services, and are these areas spatially concordant across services? (ii) Where on the landscape are the strongest tradeoffs and synergies among ecosystem services located? (iii) For ecosystem service pairs that experience tradeoffs, what distinguishes locations that are "win-win" exceptions from other locations? Spatial patterns of high supply for multiple ecosystem services often were not coincident; locations where six or more services were produced at high levels (upper 20th percentile) occupied only 3.3% of the landscape. Most relationships among ecosystem services were synergies, but tradeoffs occurred between crop production and water quality. Ecosystem services related to water quality and quantity separated into three different groups, indicating that management to sustain freshwater services along with other ecosystem services will not be simple. Despite overall tradeoffs between crop production and water quality, some locations were positive for both, suggesting that tradeoffs are not inevitable everywhere and might be ameliorated in some locations. Overall, we found that different areas of the landscape supplied different suites of ecosystem services, and their lack of spatial concordance suggests the importance of managing over large areas to sustain multiple ecosystem services.

  17. Ecological feedbacks. Termite mounds can increase the robustness of dryland ecosystems to climatic change.

    Science.gov (United States)

    Bonachela, Juan A; Pringle, Robert M; Sheffer, Efrat; Coverdale, Tyler C; Guyton, Jennifer A; Caylor, Kelly K; Levin, Simon A; Tarnita, Corina E

    2015-02-06

    Self-organized spatial vegetation patterning is widespread and has been described using models of scale-dependent feedback between plants and water on homogeneous substrates. As rainfall decreases, these models yield a characteristic sequence of patterns with increasingly sparse vegetation, followed by sudden collapse to desert. Thus, the final, spot-like pattern may provide early warning for such catastrophic shifts. In many arid ecosystems, however, termite nests impart substrate heterogeneity by altering soil properties, thereby enhancing plant growth. We show that termite-induced heterogeneity interacts with scale-dependent feedbacks to produce vegetation patterns at different spatial grains. Although the coarse-grained patterning resembles that created by scale-dependent feedback alone, it does not indicate imminent desertification. Rather, mound-field landscapes are more robust to aridity, suggesting that termites may help stabilize ecosystems under global change. Copyright © 2015, American Association for the Advancement of Science.

  18. Ecological health status of the Lagos wetland ecosystems: Implications for coastal risk reduction

    Science.gov (United States)

    Agboola, Julius I.; Ndimele, Prince E.; Odunuga, Shakirudeen; Akanni, Adeniran; Kosemani, Bosede; Ahove, Michael A.

    2016-12-01

    Lagos, a major urban agglomeration in the world is characterized by wetlands and basin for upstream rivers such as Ogun, Oshun and Yewa Rivers. Ongoing environmental pressures exerted by large-scale land reclamation for residential quarters, refuse and sewage dumping, and other uses, however, are suspected to have had a substantial impact on ecological health of the Lagos wetland ecosystems over the last few decades. To determine the impact of these pressures, we examined spatial changes in three wetlands areas- Badore/Langbasa (BL), Festac/Iba/Ijegun (FI) and Ologe/Otto-Awori (OO) through field sample collection and analyses of surface water, sediments, air-water interface gas fluxes and vegetations. Surface water conductivity, total suspended solids (TSS), alkalinity, chloride, biological oxygen demand (BOD), nitrate, phosphate and heavy metals (Zn, Cu, Fe, Na, Mn, Pb, Cd, K and Ni) exhibited relative spatial stability while other water quality parameters varied significantly (P International Union for Conservation of Nature (IUCN). There are indications of steady rise in greenhouse gas levels in Lagos since air CO2 value at BL have reached global threshold of 400 ppm with OO and FI closely approaching. We conclude that the Lagos wetland ecosystems, especially OO and FI still have some semblance of natural habitat. However, further destruction and unwise use of the resources could cause damage to physical, chemical, geological and biological processes in nature, which could result to grave socio-economic and cultural consequences to the local communities whose livelihood and lifestyle depend on these valued wetlands.

  19. Reprint of Ecological health status of the Lagos wetland ecosystems: Implications for coastal risk reduction

    Science.gov (United States)

    Agboola, Julius I.; Ndimele, Prince E.; Odunuga, Shakirudeen; Akanni, Adeniran; Kosemani, Bosede; Ahove, Michael A.

    2016-12-01

    Lagos, a major urban agglomeration in the world is characterized by wetlands and basin for upstream rivers such as Ogun, Oshun and Yewa Rivers. Ongoing environmental pressures exerted by large-scale land reclamation for residential quarters, refuse and sewage dumping, and other uses, however, are suspected to have had a substantial impact on ecological health of the Lagos wetland ecosystems over the last few decades. To determine the impact of these pressures, we examined spatial changes in three wetlands areas- Badore/Langbasa (BL), Festac/Iba/Ijegun (FI) and Ologe/Otto-Awori (OO) through field sample collection and analyses of surface water, sediments, air-water interface gas fluxes and vegetations. Surface water conductivity, total suspended solids (TSS), alkalinity, chloride, biological oxygen demand (BOD), nitrate, phosphate and heavy metals (Zn, Cu, Fe, Na, Mn, Pb, Cd, K and Ni) exhibited relative spatial stability while other water quality parameters varied significantly (P International Union for Conservation of Nature (IUCN). There are indications of steady rise in greenhouse gas levels in Lagos since air CO2 value at BL have reached global threshold of 400 ppm with OO and FI closely approaching. We conclude that the Lagos wetland ecosystems, especially OO and FI still have some semblance of natural habitat. However, further destruction and unwise use of the resources could cause damage to physical, chemical, geological and biological processes in nature, which could result to grave socio-economic and cultural consequences to the local communities whose livelihood and lifestyle depend on these valued wetlands.

  20. Revising ecological assumptions about Human papillomavirus interactions and type replacement.

    Science.gov (United States)

    Murall, Carmen Lía; McCann, Kevin S; Bauch, Chris T

    2014-06-07

    The controversy over whether vaccine-targeted HPV types will be replaced by other oncogenic, non-vaccine-targeted types remains unresolved. This is in part because little is known about the ecology of HPV types. Patient data has been interpreted to suggest independence or facilitative interactions between types and therefore replacement is believed to be unlikely. With a novel mathematical model, we investigated which HPV type interactions and their immune responses gave qualitatively similar patterns frequently observed in patients. To assess the possibility of type replacement, vaccination was added to see if non-vaccine-targeted types increased their 'niche'. Our model predicts that independence and facilitation are not necessary for the coexistence of types inside hosts, especially given the patchy nature of HPV infection. In fact, independence and facilitation inadequately represented co-infected patients. We found that some form of competition is likely in natural co-infections. Hence, non-vaccine-targeted types that are not cross-reactive with the vaccine could spread to more patches and can increase their viral load in vaccinated hosts. The degree to which this happens will depend on replication and patch colonization rates. Our results suggest that independence between types could be a fallacy, and so without conclusively untangling HPV within-host ecology, type replacement remains theoretically viable. More ecological thinking is needed in future studies. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Planning Water Resources in an Agroforest Ecosystem for Improvement of Regional Ecological Function Under Uncertainties

    Directory of Open Access Journals (Sweden)

    Xueting Zeng

    2018-04-01

    Full Text Available In this study, an agroforestry ecosystem project (AEP is developed for confronting the conflict between agricultural development and forest protection. A fuzzy stochastic programming with Laplace scenario analysis (FSL is proposed for planning water resources in an AEP issue under uncertainties. FSL can not only deal with spatial and temporal variations of hydrologic elements and meteorological conditions; but also handle uncertainties that are expressed in terms of probability, possibility distributions and fuzzy sets; meanwhile, policy scenario analysis with Laplace’s criterion (PSL is introduced to handle probability of each scenario occurrence under the supposition of no data available. The developed FSL can be applied to an AEP issue in Xixian county, located in north of China. The result of ecological effects, water allocation patterns, pollution mitigation schemes and system benefits under various scenarios are obtained, which can support policymakers adjusting current strategy to improve regional ecological function with cost-effective and sustainable manners. Meanwhile, it can support generating a robust water plan for regional sustainability in an AEP issue under uncertainties.

  2. A review of ecological effects and environmental fate of illicit drugs in aquatic ecosystems.

    Science.gov (United States)

    Rosi-Marshall, E J; Snow, D; Bartelt-Hunt, S L; Paspalof, A; Tank, J L

    2015-01-23

    Although illicit drugs are detected in surface waters throughout the world, their environmental fate and ecological effects are not well understood. Many illicit drugs and their breakdown products have been detected in surface waters and temporal and spatial variability in use translates into "hot spots and hot moments" of occurrence. Illicit drug occurrence in regions of production and use and areas with insufficient wastewater treatment are not well studied and should be targeted for further study. Evidence suggests that illicit drugs may not be persistent, as their half-lives are relatively short, but may exhibit "pseudo-persistence" wherein continual use results in persistent occurrence. We reviewed the literature on the ecological effects of these compounds on aquatic organisms and although research is limited, a wide array of aquatic organisms, including bacteria, algae, invertebrates, and fishes, have receptors that make them potentially sensitive to these compounds. In summary, illicit drugs occur in surface waters and aquatic organisms may be affected by these compounds; research is needed that focuses on concentrations of illicit drugs in areas of production and high use, environmental fate of these compounds, and effects of these compounds on aquatic ecosystems at the concentrations that typically occur in the environment. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Focusing Conservation Efforts on Ecosystem Service Supply May Increase Vulnerability of Socio-Ecological Systems.

    Directory of Open Access Journals (Sweden)

    Pedro Laterra

    Full Text Available Growing concern about the loss of ecosystem services (ES promotes their spatial representation as a key tool for the internalization of the ES framework into land use policies. Paradoxically, mapping approaches meant to inform policy decisions focus on the magnitude and spatial distribution of the biophysical supply of ES, largely ignoring the social mechanisms by which these services influence human wellbeing. If social mechanisms affecting ES demand, enhancing it or reducing it, are taken more into account, then policies are more effective. By developing and applying a new mapping routine to two distinct socio-ecological systems, we show a strong spatial uncoupling between ES supply and socio-ecological vulnerability to the loss of ES, under scenarios of land use and cover change. Public policies based on ES supply might not only fail at detecting priority conservation areas for the wellbeing of human societies, but may also increase their vulnerability by neglecting areas of currently low, but highly valued ES supply.

  4. Bridging the gap between theoretical ecology and real ecosystems: modeling invertebrate community composition in streams.

    Science.gov (United States)

    Schuwirth, Nele; Reichert, Peter

    2013-02-01

    For the first time, we combine concepts of theoretical food web modeling, the metabolic theory of ecology, and ecological stoichiometry with the use of functional trait databases to predict the coexistence of invertebrate taxa in streams. We developed a mechanistic model that describes growth, death, and respiration of different taxa dependent on various environmental influence factors to estimate survival or extinction. Parameter and input uncertainty is propagated to model results. Such a model is needed to test our current quantitative understanding of ecosystem structure and function and to predict effects of anthropogenic impacts and restoration efforts. The model was tested using macroinvertebrate monitoring data from a catchment of the Swiss Plateau. Even without fitting model parameters, the model is able to represent key patterns of the coexistence structure of invertebrates at sites varying in external conditions (litter input, shading, water quality). This confirms the suitability of the model concept. More comprehensive testing and resulting model adaptations will further increase the predictive accuracy of the model.

  5. Exposure to Violence across the Social Ecosystem and the Development of Aggression: A Test of Ecological Theory in the Israeli-Palestinian Conflict

    Science.gov (United States)

    Boxer, Paul; Huesmann, L. Rowell; Dubow, Eric F.; Landau, Simha F.; Gvirsman, Shira Dvir; Shikaki, Khalil; Ginges, Jeremy

    2013-01-01

    Bronfenbrenner's (1979) ecological model proposes that events in higher order social ecosystems should influence human development through their impact on events in lower order social ecosystems. This proposition was tested with respect to ecological violence and the development of children's aggression via analyses of 3 waves of data (1 wave…

  6. Biomechanical warfare in ecology; negative interactions between species by habitat modification

    NARCIS (Netherlands)

    van Wesenbeeck, B. K.; van de Koppel, J.; Herman, P. M. J.; Bakker, J. P.; Bouma, T. J.

    Since the introduction of the term ecosystem engineering by Jones et al. many studies have focused on positive, facilitative interactions caused by ecosystem engineering. Much less emphasis has been placed on the role of ecosystem engineering in causing negative interactions between species. Here,

  7. Biomechanical warfare in ecology; negative interactions between species by habitat modification

    NARCIS (Netherlands)

    Van Wesenbeeck, B.K.; Van de Koppel, J.; Herman, P.M.J.; Bakker, J.P.; Bouma, T.J.

    2007-01-01

    Since the introduction of the term ecosystem engineering by Jones et al. many studies have focused on positive, facilitative interactions caused by ecosystem engineering. Much less emphasis has been placed on the role of ecosystem engineering in causing negative interactions between species. Here,

  8. Ecological function as a target for ecosystem-based management: Defining when change matters in decision making

    Science.gov (United States)

    Ecosystem-based management (EBM) accounts for both direct and indirect drivers of ecological change for decision making. Just as with direct management of a resource, EBM requires a definition of management thresholds that define when change in function is sufficient to merit ma...

  9. Findings Brief External Review of the Ecosystem Approaches to ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    External Review of the Ecosystem Approaches to Human. Health Program ... Improved understanding of social, political, economic, and ecological interactions and .... global learning, communication among partners and others stakeholders.

  10. Biotic Interactions Shape the Ecological Distributions of Staphylococcus Species.

    Science.gov (United States)

    Kastman, Erik K; Kamelamela, Noelani; Norville, Josh W; Cosetta, Casey M; Dutton, Rachel J; Wolfe, Benjamin E

    2016-10-18

    Many metagenomic sequencing studies have observed the presence of closely related bacterial species or genotypes in the same microbiome. Previous attempts to explain these patterns of microdiversity have focused on the abiotic environment, but few have considered how biotic interactions could drive patterns of microbiome diversity. We dissected the patterns, processes, and mechanisms shaping the ecological distributions of three closely related Staphylococcus species in cheese rind biofilms. Paradoxically, the most abundant species (S. equorum) is the slowest colonizer and weakest competitor based on growth and competition assays in the laboratory. Through in vitro community reconstructions, we determined that biotic interactions with neighboring fungi help resolve this paradox. Species-specific stimulation of the poor competitor by fungi of the genus Scopulariopsis allows S. equorum to dominate communities in vitro as it does in situ Results of comparative genomic and transcriptomic experiments indicate that iron utilization pathways, including a homolog of the S. aureus staphyloferrin B siderophore operon pathway, are potential molecular mechanisms underlying Staphylococcus-Scopulariopsis interactions. Our integrated approach demonstrates that fungi can structure the ecological distributions of closely related bacterial species, and the data highlight the importance of bacterium-fungus interactions in attempts to design and manipulate microbiomes. Decades of culture-based studies and more recent metagenomic studies have demonstrated that bacterial species in agriculture, medicine, industry, and nature are unevenly distributed across time and space. The ecological processes and molecular mechanisms that shape these distributions are not well understood because it is challenging to connect in situ patterns of diversity with mechanistic in vitro studies in the laboratory. Using tractable cheese rind biofilms and a focus on coagulase-negative staphylococcus (CNS

  11. Two prototype tools for assessing good environmental/ecological status (GES) in aquatic ecosystems – DEVOTES and WATERS

    DEFF Research Database (Denmark)

    Murray, Ciarán; Carstensen, Jacob; Andersen, Jesper

    2015-01-01

    -based tools, which classify ecological/environmental status in two classes (good or not good) and five classes (High, Good, Moderate, Poor or Bad) by comparing observed indicator values with specified status classification boundaries. Assessments are made for geographical entities (“sectors” in DEVOTES......We present two prototype tools for assessment of GES (good ecological status and good environmental status) in aquatic ecosystems: the DEVOTES biodiversity assessment tool (for the MSFD) and the WATERS ecological status assessment tool (for the WFD). Both tools are multi-metric indicator...... for sub-division of sectors and habitat types into hierarchical structures. The DEVOTES tool weights indicator results from different sectors according to their geographical extent and/or assigned quantitative value scores. The DEVOTES tool allows the assessment to be targeted to a particular ecosystem...

  12. Transient Social-Ecological Stability: the Effects of Invasive Species and Ecosystem Restoration on Nutrient Management Compromise in Lake Erie

    Directory of Open Access Journals (Sweden)

    Eric D. Roy

    2010-03-01

    Full Text Available Together, lake ecosystems and local human activity form complex social-ecological systems (SESs characterized by feedback loops and discontinuous change. Researchers in diverse fields have suggested that complex systems do not have single stable equilibria in the long term because of inevitable perturbation. During this study, we sought to address the general question of whether or not stable social-ecological equilibria exist in highly stressed and managed lacustrine systems. Using an integrated human-biophysical model, we investigated the impacts of a species invasion and ecosystem restoration on SES equilibrium, defined here as a compromise in phosphorus management among opposing stakeholders, in western Lake Erie. Our integrated model is composed of a calibrated ecological submodel representing Sandusky Bay, and a phosphorus management submodel that reflects the societal benefits and costs of phosphorus regulation. These two submodels together form a dynamic feedback loop that includes freshwater ecology, ecosystem services, and phosphorus management. We found that the invasion of dreissenid mussels decreased ecosystem resistance to eutrophication, necessitating increased phosphorus management to preserve ecosystem services and thus creating the potential for a shift in social-ecological equilibrium. Additionally, our results suggest that net benefits in the region following the invasion of dreissenids may never again reach the pre-invasion level if on-site phosphorus control is the sole management lever. Further demonstrating transient system stability, large-scale wetland restoration shifted points of management compromise to states characterized by less on-site phosphorus management and higher environmental quality, resulting in a significant increase in net benefits in the region. We conclude that lacustrine SESs are open and dynamic, and we recommend that future models of these systems emphasize site-specific perturbation over

  13. Chemical ecology of insect-plant interactions: ecological significance of plant secondary metabolites.

    Science.gov (United States)

    Nishida, Ritsuo

    2014-01-01

    Plants produce a diverse array of secondary metabolites as chemical barriers against herbivores. Many phytophagous insects are highly adapted to these allelochemicals and use such unique substances as the specific host-finding cues, defensive substances of their own, and even as sex pheromones or their precursors by selectively sensing, incorporating, and/or processing these phytochemicals. Insects also serve as pollinators often effectively guided by specific floral fragrances. This review demonstrates the ecological significance of such plant secondary metabolites in the highly diverse interactions between insects and plants.

  14. Dental biofilm: ecological interactions in health and disease.

    Science.gov (United States)

    Marsh, P D; Zaura, Egija

    2017-03-01

    The oral microbiome is diverse and exists as multispecies microbial communities on oral surfaces in structurally and functionally organized biofilms. To describe the network of microbial interactions (both synergistic and antagonistic) occurring within these biofilms and assess their role in oral health and dental disease. PubMed database was searched for studies on microbial ecological interactions in dental biofilms. The search results did not lend themselves to systematic review and have been summarized in a narrative review instead. Five hundred and forty-seven original research articles and 212 reviews were identified. The majority (86%) of research articles addressed bacterial-bacterial interactions, while inter-kingdom microbial interactions were the least studied. The interactions included physical and nutritional synergistic associations, antagonism, cell-to-cell communication and gene transfer. Oral microbial communities display emergent properties that cannot be inferred from studies of single species. Individual organisms grow in environments they would not tolerate in pure culture. The networks of multiple synergistic and antagonistic interactions generate microbial inter-dependencies and give biofilms a resilience to minor environmental perturbations, and this contributes to oral health. If key environmental pressures exceed thresholds associated with health, then the competitiveness among oral microorganisms is altered and dysbiosis can occur, increasing the risk of dental disease. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. Development of concepts of plants activity, its ecological role and methods of its assessment in ecosystems

    Directory of Open Access Journals (Sweden)

    Savinov Alexander

    2017-09-01

    Full Text Available When studying the species activity in the phytocoenoses, three methodological approaches are used: coenotipic, status and ergontic. The latter is proposed for the first time and based on the fact that the activity of plant organisms of a given species is considered as a set of interactions of these organisms with each other, with other organisms and abiotic components of ecosystems. This interaction essentially reflects the rate of accumulation and generation of substances, energy and information by plant organisms. To calculate the activity of the plant species in this aspect, the appropriate formulas were proposed. When comparing the coenotipic, status and ergontic approaches, it was stated that these approaches can complement each other.

  16. Priorities for research in soil ecology

    NARCIS (Netherlands)

    Eisenhauer, N.; Antunes, P.M.; Bennett, A.E.; Birkhofer, K.; Bisset, A.; Bowker, M.A.; T., Caruso; B., Chen; Coleman, D.C.; W., De Boer; van Straalen, N.M.

    2017-01-01

    The ecological interactions that occur in and with soil are of consequence in many ecosystems on the planet. These interactions provide numerous essential ecosystem services, and the sustainable management of soils has attracted increasing scientific and public attention. Although soil ecology

  17. Preserving and maintaining vital Ecosystem Services: the importance of linking knowledge from Geosciences and social-ecological System analysis

    Science.gov (United States)

    Finger, David; Petursdottir, Thorunn

    2013-04-01

    Human kind has always been curios and motivated to understand and quantify environmental processes in order to predict and anticipate the evolution of vital ecosystem services. Even the very first civilizations used empirical correlations to predict outcomes of rains and subsequent harvest efficiencies. Along with the insights into the functioning of ecosystems, humans also became aware that their anthropogenic activities can have positive and negative impact on ecosystem services. In recent years, geosciences have brought forward new sophisticated observations and modeling tools, with the aim to improve predictions of ecological developments. At the same time, the added value of linking ecological factors to the surrounding social structure has received a growing acceptance among scientists. A social-ecological system approach brings in a holistic understanding of how these systems are inevitably interlinked and how their sustainability can be better maintained. We claim that the biggest challenge for geoscience in the coming decades will be to link these two disciplines in order to establish adequate strategies to preserve natural ecosystems and their services, parallel to their utilization. We will present various case studies from more than a decade of research, ranging from water quality in mountain lakes, climate change impacts on water availability and declining fishing yields in freshwaters and discuss how the studies outcomes could be given added value by interpreting them via social-ecological system analysis. For instance, sophisticated field investigations revealed that deep water mixing in lake Issyk-Kul, Kirgizstan, is intensively distributing pollutants in the entire lake. Although fishery is an important sector in the region, the local awareness of the importance of water quality is low. In Switzerland, strict water protection laws led to ologotrophication of alpine lakes, reducing fishing yields. While local fishermen argued that local fishery is

  18. New ecological mechanism of formation of spatial distribution of radionuclides in river ecosystem

    International Nuclear Information System (INIS)

    Degermendzhy, A.G.; Shevyrnogov, A.P.; Kosolapova, L.G.; Levin, L.A.; Chernousov, A.V.; Vlasik, P.V.

    1996-01-01

    Radioecological expeditions on the Yenissei river revealed 'spotty' distribution of radioisotopes in bottom sediments and along the coastline of the river. This work presents results of theoretical analysis of the formation mechanism of stable spatial non-uniformities of river ecosystem components by population interactions of 'predator-prey' type between the phytoplukton and zooplankton. 'Patchiness contrast' (i.e. the amplitude of the radionuclide spatial propagation wave in the water) for the large oscillations control by increasing or decreasing current velocity depends both on the boundary concentrations of phytoplankton and zooplankton and on the established nature of their interpopulation interactions (or coefficients of interactions). Variation of the below given interaction parameters within the 'phytoplanbon-zooplankton' system makes increase the amplitude of spatial distribution wave: decrease of algal growth rate; increase of algal death rate; decrease of zooplankton death rate; increase of interaction coefficients. It was shown for small oscillations that the period of component distribution waves is in proportion to the current velocity and the amplitude of 'small' waves does not depend on the water current velocity. Theoretically it has been also found that with deep limitation of phytoplankton growth by biogenous elements the 'standing wave' is observed to deteriorate and monotonous distribution of radionuclide concentration fields is found to form. (author)

  19. Bubble Curtains: Herbivore Exclusion Devices for Ecology and Restoration of Marine Ecosystems?

    Directory of Open Access Journals (Sweden)

    Scott Bennett

    2017-09-01

    Full Text Available Herbivorous fishes play a critical role in maintaining or disrupting the ecological resilience of many kelp forests, coral reefs and seagrass ecosystems, worldwide. The increasing rate and scale of benthic habitat loss under global change has magnified the importance of herbivores and highlights the need to study marine herbivory at ecologically relevant scales. Currently, underwater herbivore exclusions (or inclusions have been restricted to small scale experimental plots, in large part due to the challenges of designing structures that can withstand the physical forces of waves and currents, without drastically altering the physical environment inside the exclusion area. We tested the ability of bubble curtains to deter herbivorous fishes from feeding on seaweeds as an alternative to the use of rigid exclusion cages. Kelps (Ecklonia radiata were transplanted onto reefs with high browsing herbivore pressure into either unprotected plots, exclusion cages or plots protected by bubble curtains of 0.785 m2 and 3.14 m2. Remote underwater video was used to compare the behavioral response of fishes to kelps protected and unprotected by bubble curtains. Kelp biomass loss was significantly lower inside the bubble curtains compared to unprotected kelps and did not differ from kelp loss rates in traditional exclusion cages. Consistent with this finding, no herbivorous fishes were observed entering into the bubble curtain at any point during the experiment. In contrast, fish bite rates on unprotected kelps were 1,621 ± 702 bites h−1 (mean ± SE. Our study provides initial evidence that bubble curtains can exclude herbivorous fishes, paving the way for future studies to examine their application at larger spatial and temporal scales, beyond what has been previously feasible using traditional exclusion cages.

  20. Ecological interactions in Aedes species on Reunion Island.

    Science.gov (United States)

    Bagny Beilhe, L; Delatte, H; Juliano, S A; Fontenille, D; Quilici, S

    2013-12-01

    Two invasive, container-breeding mosquito species, Aedes aegypti (Stegomyia aegypti) and Aedes albopictus (Stegomyia albopicta) (Diptera: Culicidae), have different distribution patterns on Reunion Island. Aedes albopictus occurs in all areas and Ae. aegypti colonizes only some restricted areas already occupied by Ae. albopictus. This study investigates the abiotic and biotic ecological mechanisms that determine the distribution of Aedes species on Reunion Island. Life history traits (duration of immature stages, survivorship, fecundity, estimated finite rate of increase) in Ae. aegypti and Ae. albopictus were compared at different temperatures. These fitness measures were characterized in both species in response to competitive interactions among larvae. Aedes aegypti was drastically affected by temperature, performing well only at around 25 °C, at which it achieved its highest survivorship and greatest estimated rate of increase. The narrow distribution of this species in the field on Reunion Island may thus relate to its poor ability to cope with unfavourable temperatures. Aedes aegypti was also more negatively affected by high population densities and to some extent by interactions with Ae. albopictus, particularly in the context of limited food supplies. Aedes albopictus exhibited better population performance across a range of environmental conditions. Its ecological plasticity and its superior competitive ability relative to its congener may further enhance its invasion success on Reunion Island. © 2012 The Royal Entomological Society.

  1. Regular pattern formation in real ecosystems

    NARCIS (Netherlands)

    Rietkerk, Max; Koppel, Johan van de

    2008-01-01

    Localized ecological interactions can generate striking large-scale spatial patterns in ecosystems through spatial self-organization. Possible mechanisms include oscillating consumer–resource interactions, localized disturbance-recovery processes and scale-dependent feedback. Despite abundant

  2. Functional and ecological consequences of saprotrophic fungus-grazer interactions.

    Science.gov (United States)

    Crowther, Thomas W; Boddy, Lynne; Hefin Jones, T

    2012-11-01

    Saprotrophic fungi are key regulators of nutrient cycling in terrestrial ecosystems. They are the primary agents of plant litter decomposition and their hyphal networks, which grow throughout the soil-litter interface, represent highly dynamic channels through which nutrients are readily distributed. By ingesting hyphae and dispersing spores, soil invertebrates, including Arthropoda, Oligochaetae and Nematoda, influence fungal-mediated nutrient distribution within soil. Fungal physiological responses to grazing include changes to hydrolytic enzyme production and respiration rates. These directly affect nutrient mineralisation and the flux of CO(2) between terrestrial and atmospheric pools. Preferential grazing may also exert selective pressures on saprotrophic communities, driving shifts in fungal succession and community composition. These functional and ecological consequences of grazing are intrinsically linked, and influenced by invertebrate grazing intensity. High-intensity grazing often reduces fungal growth and activity, whereas low-intensity grazing can have stimulatory effects. Grazing intensity is directly related to invertebrate abundance, and varies dramatically between species and functional groups. Invertebrate diversity and community composition, therefore, represent key factors determining the functioning of saprotrophic fungal communities and the services they provide.

  3. Above and belowground connections and species interactions: Controls over ecosystem fluxes

    Energy Technology Data Exchange (ETDEWEB)

    Trowbridge, Amy Marie [Montana State Univ., Bozeman, MT (United States); Phillips, Richard [Indiana Univ., Bloomington, IN (United States); Stoy, Paul Christopher [Montana State Univ., Bozeman, MT (United States)

    2016-11-01

    The ultimate goal of this work was to quantify soil and volatile organic compound fluxes as a function of tree species and associated mycorrhizal associations in an intact forest, but also to describe the physical and biological factors that control these emissions. The results of this research lay the foundation toward an improved mechanistic understanding of carbon pathways, fluxes, and ecosystem function, ultimately improving the representation of forest ecosystems in Earth System models. To this end, a multidisciplinary approach was necessary to fill a critical gap in our understanding of how soil and root processes may influence whole-ecosystem carbon-based volatile fluxes in the face of a rapidly changing climate. We developed a series of novel sampling protocols and coupled a variety of advanced analytical techniques, resulting in findings relevant across disciplines. Furthermore, we leveraged existing infrastructure, research sites, and datasets to design a low-cost exploratory project that links belowground processes, soil volatile emissions, and total ecosystem carbon budgets. Measurements from soil collars installed across a species/mycorrhizal gradient at the DOE-supported Moran Monroe State Forest Ameriflux tower site suggest that leaf litter is the primary source of belowground and forest floor volatile emissions, but the strength of this source is significantly affected not only by leaf litter type, but the strength of the soil as a sink. Results suggest that the strength of the sink is influenced by tree species-specific associated microbial communities that change throughout the season as a function of temperature, soil moisture, leaf litter inputs, and phenology. The magnitude of the observed volatile fluxes from the forest floor is small relative to total aboveground ecosystem flux, but the contribution of these emissions to volatile-mediated ecological interactions and soil processes (e.g. nitrification) varies substantially across the growing

  4. Cloud Coverage Acts as an Amplifier for Ecological Light Pollution in Urban Ecosystems

    Science.gov (United States)

    Kyba, Christopher C. M.; Ruhtz, Thomas; Fischer, Jürgen; Hölker, Franz

    2011-01-01

    The diurnal cycle of light and dark is one of the strongest environmental factors for life on Earth. Many species in both terrestrial and aquatic ecosystems use the level of ambient light to regulate their metabolism, growth, and behavior. The sky glow caused by artificial lighting from urban areas disrupts this natural cycle, and has been shown to impact the behavior of organisms, even many kilometers away from the light sources. It could be hypothesized that factors that increase the luminance of the sky amplify the degree of this “ecological light pollution”. We show that cloud coverage dramatically amplifies the sky luminance, by a factor of 10.1 for one location inside of Berlin and by a factor of 2.8 at 32 km from the city center. We also show that inside of the city overcast nights are brighter than clear rural moonlit nights, by a factor of 4.1. These results have important implications for choronobiological and chronoecological studies in urban areas, where this amplification effect has previously not been considered. PMID:21399694

  5. Ecological Variability and Carbon Stock Estimates of Mangrove Ecosystems in Northwestern Madagascar

    Directory of Open Access Journals (Sweden)

    Trevor G. Jones

    2014-01-01

    Full Text Available Mangroves are found throughout the tropics, providing critical ecosystem goods and services to coastal communities and supporting rich biodiversity. Despite their value, world-wide, mangroves are being rapidly degraded and deforested. Madagascar contains approximately 2% of the world’s mangroves, >20% of which has been deforested since 1990 from increased extraction for charcoal and timber and conversion to small to large-scale agriculture and aquaculture. Loss is particularly prominent in the northwestern Ambaro and Ambanja bays. Here, we focus on Ambaro and Ambanja bays, presenting dynamics calculated using United States Geological Survey (USGS national-level mangrove maps and the first localized satellite imagery derived map of dominant land-cover types. The analysis of USGS data indicated a loss of 7659 ha (23.7% and a gain of 995 ha (3.1% from 1990–2010. Contemporary mapping results were 93.4% accurate overall (Kappa 0.9, with producer’s and user’s accuracies ≥85%. Classification results allowed partitioning mangroves in to ecologically meaningful, spectrally distinct strata, wherein field measurements facilitated estimating the first total carbon stocks for mangroves in Madagascar. Estimates suggest that higher stature closed-canopy mangroves have average total vegetation carbon values of 146.8 Mg/ha (±10.2 and soil organic carbon of 446.2 (±36.9, supporting a growing body of studies that mangroves are amongst the most carbon-dense tropical forests.

  6. Cloud coverage acts as an amplifier for ecological light pollution in urban ecosystems.

    Science.gov (United States)

    Kyba, Christopher C M; Ruhtz, Thomas; Fischer, Jürgen; Hölker, Franz

    2011-03-02

    The diurnal cycle of light and dark is one of the strongest environmental factors for life on Earth. Many species in both terrestrial and aquatic ecosystems use the level of ambient light to regulate their metabolism, growth, and behavior. The sky glow caused by artificial lighting from urban areas disrupts this natural cycle, and has been shown to impact the behavior of organisms, even many kilometers away from the light sources. It could be hypothesized that factors that increase the luminance of the sky amplify the degree of this "ecological light pollution". We show that cloud coverage dramatically amplifies the sky luminance, by a factor of 10.1 for one location inside of Berlin and by a factor of 2.8 at 32 km from the city center. We also show that inside of the city overcast nights are brighter than clear rural moonlit nights, by a factor of 4.1. These results have important implications for choronobiological and chronoecological studies in urban areas, where this amplification effect has previously not been considered.

  7. Improving the effectiveness of ecological site descriptions: General state-and-transition models and the Ecosystem Dynamics Interpretive Tool (EDIT)

    Science.gov (United States)

    Bestelmeyer, Brandon T.; Williamson, Jeb C.; Talbot, Curtis J.; Cates, Greg W.; Duniway, Michael C.; Brown, Joel R.

    2016-01-01

    State-and-transition models (STMs) are useful tools for management, but they can be difficult to use and have limited content.STMs created for groups of related ecological sites could simplify and improve their utility. The amount of information linked to models can be increased using tables that communicate management interpretations and important within-group variability.We created a new web-based information system (the Ecosystem Dynamics Interpretive Tool) to house STMs, associated tabular information, and other ecological site data and descriptors.Fewer, more informative, better organized, and easily accessible STMs should increase the accessibility of science information.

  8. Modelling Carbon Emissions in Calluna vulgaris–Dominated Ecosystems when Prescribed Burning and Wildfires Interact

    Science.gov (United States)

    Santana, Victor M.; Alday, Josu G.; Lee, HyoHyeMi; Allen, Katherine A.; Marrs, Rob H.

    2016-01-01

    A present challenge in fire ecology is to optimize management techniques so that ecological services are maximized and C emissions minimized. Here, we modeled the effects of different prescribed-burning rotation intervals and wildfires on carbon emissions (present and future) in British moorlands. Biomass-accumulation curves from four Calluna-dominated ecosystems along a north-south gradient in Great Britain were calculated and used within a matrix-model based on Markov Chains to calculate above-ground biomass-loads and annual C emissions under different prescribed-burning rotation intervals. Additionally, we assessed the interaction of these parameters with a decreasing wildfire return intervals. We observed that litter accumulation patterns varied between sites. Northern sites (colder and wetter) accumulated lower amounts of litter with time than southern sites (hotter and drier). The accumulation patterns of the living vegetation dominated by Calluna were determined by site-specific conditions. The optimal prescribed-burning rotation interval for minimizing annual carbon emissions also differed between sites: the optimal rotation interval for northern sites was between 30 and 50 years, whereas for southern sites a hump-backed relationship was found with the optimal interval either between 8 to 10 years or between 30 to 50 years. Increasing wildfire frequency interacted with prescribed-burning rotation intervals by both increasing C emissions and modifying the optimum prescribed-burning interval for minimum C emission. This highlights the importance of studying site-specific biomass accumulation patterns with respect to environmental conditions for identifying suitable fire-rotation intervals to minimize C emissions. PMID:27880840

  9. Modelling Carbon Emissions in Calluna vulgaris-Dominated Ecosystems when Prescribed Burning and Wildfires Interact.

    Science.gov (United States)

    Santana, Victor M; Alday, Josu G; Lee, HyoHyeMi; Allen, Katherine A; Marrs, Rob H

    2016-01-01

    A present challenge in fire ecology is to optimize management techniques so that ecological services are maximized and C emissions minimized. Here, we modeled the effects of different prescribed-burning rotation intervals and wildfires on carbon emissions (present and future) in British moorlands. Biomass-accumulation curves from four Calluna-dominated ecosystems along a north-south gradient in Great Britain were calculated and used within a matrix-model based on Markov Chains to calculate above-ground biomass-loads and annual C emissions under different prescribed-burning rotation intervals. Additionally, we assessed the interaction of these parameters with a decreasing wildfire return intervals. We observed that litter accumulation patterns varied between sites. Northern sites (colder and wetter) accumulated lower amounts of litter with time than southern sites (hotter and drier). The accumulation patterns of the living vegetation dominated by Calluna were determined by site-specific conditions. The optimal prescribed-burning rotation interval for minimizing annual carbon emissions also differed between sites: the optimal rotation interval for northern sites was between 30 and 50 years, whereas for southern sites a hump-backed relationship was found with the optimal interval either between 8 to 10 years or between 30 to 50 years. Increasing wildfire frequency interacted with prescribed-burning rotation intervals by both increasing C emissions and modifying the optimum prescribed-burning interval for minimum C emission. This highlights the importance of studying site-specific biomass accumulation patterns with respect to environmental conditions for identifying suitable fire-rotation intervals to minimize C emissions.

  10. BUSINESS TRANSFER ECOSYSTEM IN CROATIA - MISSING COMPONENTS AND INTERACTIONS

    Directory of Open Access Journals (Sweden)

    Alpeza Mirela

    2016-10-01

    Full Text Available Business transfer is an important issue that the European Commission has been actualising since the early 1990s, when the first recommendations for the improvement of national business transfer ecosystems of the EU countries were created. Neglecting business transfer as a critical phase in the development of a company can have significant negative implications for companies, their owners and wide network of stakeholders. Business transfer is a particularly important topic for the Croatian economy where more than 5,300 businesses with around 57,000 employees represent a risk group whose owners underestimate the complexity and longevity of the business transfer process. The aim of this paper is to analyse the structure and quality of the business transfer ecosystem in Croatia. For this purpose, secondary research and a qualitative study in the form of interviews with representatives of key stakeholders were conducted. The Croatian business transfer ecosystem is benchmarked to the national business transfer ecosystems of Spain, Finland, Sweden and France, based on the data collected through the EU project BTAR. The research results indicate low level of development, interconnection and complementarity of individual components of the business transfer ecosystem in Croatia. Policy recommendations for improving the quality of the business transfer ecosystem in Croatia were identified.

  11. Biological and Management Implications of Fire-Pathogen Interactions in the Giant Sequoia Ecosystem

    Science.gov (United States)

    Douglas D. Piirto; John R. Parmeter; Fields W. Cobb; Kevin L. Piper; Amy C. Workinger; William J. Otrosina

    1998-01-01

    An overriding management goal for national parks is the maintenance or, where necessary, the restoration of natural ecological processes. In Sequoia-Kings Canyon and Yosemite National Parks, there is concern about the effects of fire suppression on the giant sequoia-mixed conifer forest ecosystem. The National Park Service is currently using prescribed fire management...

  12. Sierra Nevada grasslands: interactions between livestock grazing and ecosystem structure and function

    Science.gov (United States)

    Barbara H. Allen-Diaz

    2004-01-01

    Livestock grazing plays an integral role in the grass-dominated ecosystems of the Sierra Nevada. Grazing has been asserted to influence such key ecological characteristics as water quality, net primary productivity, nutrient cycling, plant and animal diversity, wildlife habitat availability, and oak regeneration (Belsky and others 1999, Kauffmann and Krueger 1984)....

  13. Soil ecology of a rock outcrop ecosystem: Abiotic stresses, soil respiration, and microbial community profiles in limestone cedar glades

    Science.gov (United States)

    Cartwright, Jennifer M.; Advised by Dzantor, E. Kudjo

    2015-01-01

    Limestone cedar glades are a type of rock outcrop ecosystem characterized by shallow soil and extreme hydrologic conditions—seasonally ranging from xeric to saturated—that support a number of plant species of conservation concern. Although a rich botanical literature exists on cedar glades, soil biochemical processes and the ecology of soil microbial communities in limestone cedar glades have largely been ignored. This investigation documents the abiotic stress regime of this ecosystem (shallow soil, extreme hydrologic fluctuations and seasonally high soil surface temperatures) as well as soil physical and chemical characteristics, and relates both types of information to ecological structures and functions including vegetation, soil respiration, and soil microbial community metabolic profiles and diversity. Methods used in this investigation include field observations and measurements of soil physical and chemical properties and processes, laboratory analyses, and microbiological assays of soil samples.

  14. A social-ecological analysis of ecosystem services supply and trade-offs in European wood-pastures

    Science.gov (United States)

    Hartel, Tibor

    2018-01-01

    Wood-pastures are complex social-ecological systems (SES), which are the product of long-term interaction between society and its surrounding landscape. Traditionally characterized by multifunctional low-intensity management that enhanced a wide range of ecosystem services (ES), current farm management has shifted toward more intensive farm models. This study assesses the supply of ES in four study areas dominated by managed wood-pastures in Spain, Sweden, and Romania. On the basis of 144 farm surveys and the use of multivariate techniques, we characterize farm management and structure in the study areas and identify the trade-offs in ES supply associated with this management. We link these trade-offs to multiple factors that characterize the landholding: economic, social, environmental, technological, and governance. Finally, we analyze how landholders’ values and perspectives have an effect on management decisions. Results show a differentiated pattern of ES supply in the four study areas. We identified four types of trade-offs in ES supply that appear depending on what is being promoted by the farm management and that are associated with different dimensions of wood-pasture management: productivity-related trade-offs, crop production–related trade-offs, multifunctionality-related trade-offs, and farm accessibility–related trade-offs. These trade-offs are influenced by complex interactions between the properties of the SES, which have a direct influence on landholders’ perspectives and motivations. The findings of this paper advance the understanding of the dynamics between agroecosystems and society and can inform system-based agricultural and conservation policies. PMID:29732404

  15. A New Perspective on the Foraging Ecology of Apex Predators in the California Current: Results from a Fully Coupled Ecosystem Model

    Science.gov (United States)

    Fiechter, J.; Huckstadt, L. A.; Rose, K.; Costa, D. P.; Curchitser, E. N.; Hedstrom, K.; Edwards, C. A.; Moore, A. M.

    2016-02-01

    Results from a fully coupled end-to-end ecosystem model for the California Current Large Marine Ecosystem are used to describe the impact of environmental variability on the foraging ecology of its most abundant apex predator, California sea lions (Zalophus californianus). The ecosystem model consists of a biogeochemical submodel embedded in a regional ocean circulation submodel, and both coupled with a multi-species individual-based submodel for forage fish (sardine and anchovy) and California sea lions. For sea lions, bioenergetics and behavioral attributes are specified using available TOPP (Tagging Of Pacific Predators) data on their foraging patterns and diet in the California Current. Sardine and anchovy are explicitly included in the model as they represent important prey sources for California sea lions and exhibit significant interannual and decadal variability in population abundances. Output from a 20-year run (1989-2008) of the model demonstrates how different physical and biological processes control habitat utilization and foraging success of California sea lions on interannual time scales. A principal component analysis of sea lion foraging patterns indicates that the first mode of variability is alongshore and tied to sardine availability, while the second mode is cross-shore and associated with coastal upwelling intensity (a behavior consistent with male sea lion tracking data collected in 2004 vs. 2005). The results also illustrate how variability in environmental conditions and forage fish distribution affects sea lions feeding success. While specifically focusing on the foraging ecology of sea lions, our modeling framework has the ability to provide new and unique perspectives on trophic interactions in the California Current, or other regions where similar end-to-end ecosystem models may be implemented.

  16. Partial valuation of the goods and services that it provides the mangrove ecosystem: An integrated ecological-economic analysis

    International Nuclear Information System (INIS)

    Castiblanco R, Carmenza

    2002-01-01

    The article presents a methodology to value the economic benefits of the use of some goods and services that provides the mangrove ecosystem, located in the municipality of Tumaco. An ecological analysis is developed integrated to an economic evaluation that allows expressing in monetary terms some values of use of the mangrove; this value are compared with the profitability that reports the Camaroniculture, productive activity that is constituted at the moment, in the most profitable alternative use

  17. Mapping Ecological Processes and Ecosystem Services for Prioritizing Restoration Efforts in a Semi-arid Mediterranean River Basin

    Science.gov (United States)

    Trabucchi, Mattia; O'Farrell, Patrick J.; Notivol, Eduardo; Comín, Francisco A.

    2014-06-01

    Semi-arid Mediterranean regions are highly susceptible to desertification processes which can reduce the benefits that people obtain from healthy ecosystems and thus threaten human wellbeing. The European Union Biodiversity Strategy to 2020 recognizes the need to incorporate ecosystem services into land-use management, conservation, and restoration actions. The inclusion of ecosystem services into restoration actions and plans is an emerging area of research, and there are few documented approaches and guidelines on how to undertake such an exercise. This paper responds to this need, and we demonstrate an approach for identifying both key ecosystem services provisioning areas and the spatial relationship between ecological processes and services. A degraded semi-arid Mediterranean river basin in north east Spain was used as a case study area. We show that the quantification and mapping of services are the first step required for both optimizing and targeting of specific local areas for restoration. Additionally, we provide guidelines for restoration planning at a watershed scale; establishing priorities for improving the delivery of ecosystem services at this scale; and prioritizing the sub-watersheds for restoration based on their potential for delivering a combination of key ecosystem services for the entire basin.

  18. Mapping ecological processes and ecosystem services for prioritizing restoration efforts in a semi-arid Mediterranean river basin.

    Science.gov (United States)

    Trabucchi, Mattia; O'Farrell, Patrick J; Notivol, Eduardo; Comín, Francisco A

    2014-06-01

    Semi-arid Mediterranean regions are highly susceptible to desertification processes which can reduce the benefits that people obtain from healthy ecosystems and thus threaten human wellbeing. The European Union Biodiversity Strategy to 2020 recognizes the need to incorporate ecosystem services into land-use management, conservation, and restoration actions. The inclusion of ecosystem services into restoration actions and plans is an emerging area of research, and there are few documented approaches and guidelines on how to undertake such an exercise. This paper responds to this need, and we demonstrate an approach for identifying both key ecosystem services provisioning areas and the spatial relationship between ecological processes and services. A degraded semi-arid Mediterranean river basin in north east Spain was used as a case study area. We show that the quantification and mapping of services are the first step required for both optimizing and targeting of specific local areas for restoration. Additionally, we provide guidelines for restoration planning at a watershed scale; establishing priorities for improving the delivery of ecosystem services at this scale; and prioritizing the sub-watersheds for restoration based on their potential for delivering a combination of key ecosystem services for the entire basin.

  19. Socio-cultural valuation of ecosystem services in a transhumance social-ecological network

    NARCIS (Netherlands)

    Oteros Rozas, E.; Martín-López, B.; González, J.A.; Plieninger, T.; López, C.A.; Montes, C.

    2014-01-01

    The ecosystem services framework is receiving increasing attention in the fields of policy and research. The assessment of human attitudes and perceptions regarding ecosystem services has been proposed as a promising tool for addressing complex problems associated with environmental change,

  20. Improving ecosystem-scale modeling of evapotranspiration using ecological mechanisms that account for compensatory responses following disturbance

    Science.gov (United States)

    Millar, David J.; Ewers, Brent E.; Mackay, D. Scott; Peckham, Scott; Reed, David E.; Sekoni, Adewale

    2017-09-01

    Mountain pine beetle outbreaks in western North America have led to extensive forest mortality, justifiably generating interest in improving our understanding of how this type of ecological disturbance affects hydrological cycles. While observational studies and simulations have been used to elucidate the effects of mountain beetle mortality on hydrological fluxes, an ecologically mechanistic model of forest evapotranspiration (ET) evaluated against field data has yet to be developed. In this work, we use the Terrestrial Regional Ecosystem Exchange Simulator (TREES) to incorporate the ecohydrological impacts of mountain pine beetle disturbance on ET for a lodgepole pine-dominated forest equipped with an eddy covariance tower. An existing degree-day model was incorporated that predicted the life cycle of mountain pine beetles, along with an empirically derived submodel that allowed sap flux to decline as a function of temperature-dependent blue stain fungal growth. The eddy covariance footprint was divided into multiple cohorts for multiple growing seasons, including representations of recently attacked trees and the compensatory effects of regenerating understory, using two different spatial scaling methods. Our results showed that using a multiple cohort approach matched eddy covariance-measured ecosystem-scale ET fluxes well, and showed improved performance compared to model simulations assuming a binary framework of only areas of live and dead overstory. Cumulative growing season ecosystem-scale ET fluxes were 8 - 29% greater using the multicohort approach during years in which beetle attacks occurred, highlighting the importance of including compensatory ecological mechanism in ET models.

  1. Socio-cultural valuation of ecosystem services in a transhumance social-ecological network

    DEFF Research Database (Denmark)

    Oteros-Rozas, E.; Martín-López, B.; González, J.A.

    2014-01-01

    the importance of 34 ecosystem services (10 provisioning, 12 regulating, and 12 cultural) for both social and personal well-being. Overall, the ecosystem services considered to be the most important for social well-being were fire prevention, air purification and livestock. Most of the ecosystem services...

  2. Novel ecosystems: theoretical and management aspects of the new ecological world order

    Science.gov (United States)

    Richard J. Hobbs; Salvatore Arico; James Aronson; Jill S. Baron; Peter Bridgewater; Viki A. Cramer; Paul R. Epstein; John J. Ewel; Carlos A. Klink; Ariel E. Lugo; David Norton; Dennis Ojima; Richardson David M.; Eric W. Sanderson; Fernando Valladares; Montserrat Vilà; Regino Zamora; Martin Zobel

    2006-01-01

    We explore the issues relevant to those types of ecosystems containing new combinations of species that arise through human action, environmental change, and the impacts of the deliberate and inadvertent introduction of species from other regions. Novel ecosystems (also termed ‘emerging ecosystems’) result when species occur in combinations and relative abundances that...

  3. Brief communication: the ecosystem perspective in ecotoxicology as a way forward for the ecological risk assessment of chemicals.

    Science.gov (United States)

    De Laender, Frederik; Janssen, Colin R

    2013-07-01

    One of the objectives of the European Union (EU) ecological risk assessment of chemicals (ERA) is to derive maximum environmental concentrations that are not expected to cause adverse ecological effects. To this end, related EU directives list protection goals as well as guidelines that should be used to reach these goals. It is generally accepted that the individual-level endpoints on which these guidelines are based do not correspond to the listed population- and ecosystem-level protection goals. In this article, we identify 5 research topics that are key to bridging this gap: 1) the refinement of population-level effects and recovery rates by explicitly taking into account competition and 2) predation, 3) the assessment of chemical effects on biodiversity, 4) the assessment of chemical stress on ecosystem functions and services, and 5) the quantification of the effects of chemical mixtures. In addition, we illustrate why an ecosystem perspective is needed to address these topics and to inform the risk assessment process. We propose the use of existing ecotoxicological community, food web, and ecosystem models to tackle these issues and discuss why new models are needed to predict chemical effects on biodiversity. Copyright © 2013 SETAC.

  4. Remote sensing for restoration ecology: Application for restoring degraded, damaged, transformed, or destroyed ecosystems.

    Science.gov (United States)

    Reif, Molly K; Theel, Heather J

    2017-07-01

    Restoration monitoring is generally perceived as costly and time consuming, given the assumptions of successfully restoring ecological functions and services of a particular ecosystem or habitat. Opportunities exist for remote sensing to bolster the restoration science associated with a wide variety of injured resources, including resources affected by fire, hydropower operations, chemical releases, and oil spills, among others. In the last decade, the role of remote sensing to support restoration monitoring has increased, in part due to the advent of high-resolution satellite sensors as well as other sensor technology, such as lidar. Restoration practitioners in federal agencies require monitoring standards to assess restoration performance of injured resources. This review attempts to address a technical need and provides an introductory overview of spatial data and restoration metric considerations, as well as an in-depth review of optical (e.g., spaceborne, airborne, unmanned aerial vehicles) and active (e.g., radar, lidar) sensors and examples of restoration metrics that can be measured with remotely sensed data (e.g., land cover, species or habitat type, change detection, quality, degradation, diversity, and pressures or threats). To that end, the present article helps restoration practitioners assemble information not only about essential restoration metrics but also about the evolving technological approaches that can be used to best assess them. Given the need for monitoring standards to assess restoration success of injured resources, a universal monitoring framework should include a range of remote sensing options with which to measure common restoration metrics. Integr Environ Assess Manag 2017;13:614-630. Published 2016. This article is a US Government work and is in the public domain in the USA. Published 2016. This article is a US Government work and is in the public domain in the USA.

  5. Metal bioavailability in ecological risk assessment of freshwater ecosystems: From science to environmental management.

    Science.gov (United States)

    Väänänen, Kristiina; Leppänen, Matti T; Chen, XuePing; Akkanen, Jarkko

    2018-01-01

    Metal contamination in freshwater ecosystems is a global issue and metal discharges to aquatic environments are monitored in order to protect aquatic life and human health. Bioavailability is an important factor determining metal toxicity. In aquatic systems, metal bioavailability depends on local water and sediment characteristics, and therefore, the risks are site-specific. Environmental quality standards (EQS) are used to manage the risks of metals in aquatic environments. In the simplest form of EQSs, total concentrations of metals in water or sediment are compared against pre-set acceptable threshold levels. Now, however, the environmental administration bodies have stated the need to incorporate metal bioavailability assessment tools into environmental regulation. Scientific advances have been made in metal bioavailability assessment, including passive samplers and computational models, such as biotic ligand models (BLM). However, the cutting-edge methods tend to be too elaborate or laborious for standard environmental monitoring. We review the commonly used metal bioavailability assessment methods and introduce the latest scientific advances that might be applied to environmental management in the future. We present the current practices in environmental management in North America, Europe and China, highlighting the good practices and the needs for improvement. Environmental management has met these new challenges with varying degrees of success: the USA has implemented site-specific environmental risk assessment for water and sediment phases, and they have already implemented metal mixture toxicity evaluation. The European Union is promoting the use of bioavailability and BLMs in ecological risk assessment (ERA), but metal mixture toxicity and sediment phase are still mostly neglected. China has regulation only for total concentrations of metals in surface water. We conclude that there is a need for (1) Advanced and up-to-date guidelines and legislation

  6. Lessons from Philippines MPA Management: Social Ecological Interactions, Participation, and MPA Performance

    Science.gov (United States)

    Twichell, Julia; Pollnac, Richard; Christie, Patrick

    2018-06-01

    International interest in increasing marine protected area (MPA) coverage reflects broad recognition of the MPA as a key tool for marine ecosystems and fisheries management. Nevertheless, effective management remains a significant challenge. The present study contributes to enriching an understanding of best practices for MPA management through analysis of archived community survey data collected in the Philippines by the Learning Project (LP), a collaboration with United States Coral Triangle Initiative (USCTI), United States Agency for International Development (USAID), and partners. We evaluate stakeholder participation and social ecological interactions among resource users in MPA programs in the Palawan, Occidental Mindoro, and Batangas provinces in the Philippines. Analysis indicates that a complex suite of social ecological factors, including demographics, conservation beliefs, and scientifically correct knowledge influence participation, which in turn is related to perceived MPA performance. Findings indicate positive feedbacks within the system that have potential to strengthen perceptions of MPA success. The results of this evaluation provide empirical reinforcement to current inquiries concerning the role of participation in influencing MPA performance.

  7. Lessons from Philippines MPA Management: Social Ecological Interactions, Participation, and MPA Performance.

    Science.gov (United States)

    Twichell, Julia; Pollnac, Richard; Christie, Patrick

    2018-06-01

    International interest in increasing marine protected area (MPA) coverage reflects broad recognition of the MPA as a key tool for marine ecosystems and fisheries management. Nevertheless, effective management remains a significant challenge. The present study contributes to enriching an understanding of best practices for MPA management through analysis of archived community survey data collected in the Philippines by the Learning Project (LP), a collaboration with United States Coral Triangle Initiative (USCTI), United States Agency for International Development (USAID), and partners. We evaluate stakeholder participation and social ecological interactions among resource users in MPA programs in the Palawan, Occidental Mindoro, and Batangas provinces in the Philippines. Analysis indicates that a complex suite of social ecological factors, including demographics, conservation beliefs, and scientifically correct knowledge influence participation, which in turn is related to perceived MPA performance. Findings indicate positive feedbacks within the system that have potential to strengthen perceptions of MPA success. The results of this evaluation provide empirical reinforcement to current inquiries concerning the role of participation in influencing MPA performance.

  8. Ecological interactions are evolutionarily conserved across the entire tree of life.

    Science.gov (United States)

    Gómez, José M; Verdú, Miguel; Perfectti, Francisco

    2010-06-17

    Ecological interactions are crucial to understanding both the ecology and the evolution of organisms. Because the phenotypic traits regulating species interactions are largely a legacy of their ancestors, it is widely assumed that ecological interactions are phylogenetically conserved, with closely related species interacting with similar partners. However, the existing empirical evidence is inadequate to appropriately evaluate the hypothesis of phylogenetic conservatism in ecological interactions, because it is both ecologically and taxonomically biased. In fact, most studies on the evolution of ecological interactions have focused on specialized organisms, such as some parasites or insect herbivores, belonging to a limited subset of the overall tree of life. Here we study the evolution of host use in a large and diverse group of interactions comprising both specialist and generalist acellular, unicellular and multicellular organisms. We show that, as previously found for specialized interactions, generalized interactions can be evolutionarily conserved. Significant phylogenetic conservatism of interaction patterns was equally likely to occur in symbiotic and non-symbiotic interactions, as well as in mutualistic and antagonistic interactions. Host-use differentiation among species was higher in phylogenetically conserved clades, irrespective of their generalization degree and taxonomic position within the tree of life. Our findings strongly suggest a shared pattern in the organization of biological systems through evolutionary time, mediated by marked conservatism of ecological interactions among taxa.

  9. The South Florida Ecosystem Portfolio Model - A Map-Based Multicriteria Ecological, Economic, and Community Land-Use Planning Tool

    Science.gov (United States)

    Labiosa, William B.; Bernknopf, Richard; Hearn, Paul; Hogan, Dianna; Strong, David; Pearlstine, Leonard; Mathie, Amy M.; Wein, Anne M.; Gillen, Kevin; Wachter, Susan

    2009-01-01

    The South Florida Ecosystem Portfolio Model (EPM) prototype is a regional land-use planning Web tool that integrates ecological, economic, and social information and values of relevance to decision-makers and stakeholders. The EPM uses a multicriteria evaluation framework that builds on geographic information system-based (GIS) analysis and spatially-explicit models that characterize important ecological, economic, and societal endpoints and consequences that are sensitive to regional land-use/land-cover (LULC) change. The EPM uses both economics (monetized) and multiattribute utility (nonmonetized) approaches to valuing these endpoints and consequences. This hybrid approach represents a methodological middle ground between rigorous economic and ecological/ environmental scientific approaches. The EPM sacrifices some degree of economic- and ecological-forecasting precision to gain methodological transparency, spatial explicitness, and transferability, while maintaining credibility. After all, even small steps in the direction of including ecosystem services evaluation are an improvement over current land-use planning practice (Boyd and Wainger, 2003). There are many participants involved in land-use decision-making in South Florida, including local, regional, State, and Federal agencies, developers, environmental groups, agricultural groups, and other stakeholders (South Florida Regional Planning Council, 2003, 2004). The EPM's multicriteria evaluation framework is designed to cut across the objectives and knowledge bases of all of these participants. This approach places fundamental importance on social equity and stakeholder participation in land-use decision-making, but makes no attempt to determine normative socially 'optimal' land-use plans. The EPM is thus a map-based set of evaluation tools for planners and stakeholders to use in their deliberations of what is 'best', considering a balancing of disparate interests within a regional perspective. Although

  10. Modelling the dynamic interactions between food production and ecosystem services

    NARCIS (Netherlands)

    Duku, C.

    2017-01-01

    Given the high levels of food insecurity and the loss of vital ecosystem services associated with deforestation, countries in sub-Saharan Africa (SSA) face a major dilemma. How can they produce enough food in a changing climate to feed an increasing population while protecting natural forests and

  11. The metabolic and ecological interactions of oxalate-degrading bacteria in the Mammalian gut.

    Science.gov (United States)

    Miller, Aaron W; Dearing, Denise

    2013-12-06

    Oxalate-degrading bacteria comprise a functional group of microorganisms, commonly found in the gastrointestinal tract of mammals. Oxalate is a plant secondary compound (PSC) widely produced by all major taxa of plants and as a terminal metabolite by the mammalian liver. As a toxin, oxalate can have a significant impact on the health of mammals, including humans. Mammals do not have the enzymes required to metabolize oxalate and rely on their gut microbiota for this function. Thus, significant metabolic interactions between the mammalian host and a complex gut microbiota maintain the balance of oxalate in the body. Over a dozen species of gut bacteria are now known to degrade oxalate. This review focuses on the host-microbe and microbe-microbe interactions that regulate the degradation of oxalate by the gut microbiota. We discuss the pathways of oxalate throughout the body and the mammalian gut as a series of differentiated ecosystems that facilitate oxalate degradation. We also explore the mechanisms and functions of microbial oxalate degradation along with the implications for the ecological and evolutionary interactions within the microbiota and for mammalian hosts. Throughout, we consider questions that remain, as well as recent technological advances that can be employed to answer them.

  12. Environmental research programme. Ecological research. Annual report 1994. Urban-industrial landscapes, forests, agricultural landscapes, river and lake landscapes, terrestrial ecosystem research, environmental pollution and health

    International Nuclear Information System (INIS)

    1995-01-01

    In the annual report 1994 of the Federal Ministry of Research and Technology, the points of emphasis of the ecological research programme and their financing are discussed. The individual projects in the following subject areas are described in detail: urban-industrial landscapes, forests, agricultural landscapes, river and lake landscapes, other ecosystems and landscapes, terrestrial ecosystem research, environmental pollution and human health and cross-sectional activities in ecological research. (vhe) [de

  13. Effect of ecological restoration and climate change on ecosystems: a case study in the Three-Rivers Headwater Region, China.

    Science.gov (United States)

    Jiang, Chong; Zhang, Linbo

    2016-06-01

    The Three-Rivers Headwater Region (TRHR) is the headwater of the Yangtze River Basin (YARB), Yellow River Basin (YRB), and Lancang River Basin (LRB); it is known as China's 'Water Tower' owing to its important supply of freshwater. In order to assess ecosystem changes in the TRHR during 2000-2012, we systematically and comprehensively evaluated a combination of model simulation results and actual observational data. The results showed the following: (1) Ecosystem pattern was relatively stable during 2000-2010, with a slight decrease in farmland and desert areas, and a slight increase in grassland and wetland/water-body areas. (2) A warmer and wetter climate, and ecological engineering, caused the vegetation cover and productivity to significantly improve. (3) Precipitation was the main controlling factor for streamflow. A significant increase in precipitation during 2000-2012 resulted in an obvious increase in annual and seasonal streamflow. Glacier melting also contributed to the streamflow increase. (4) The total amount of soil conservation increased slightly from 2000 to 2012. The increase in precipitation caused rainfall erosivity to increase, which enhanced the intensity of soil erosion. The decrease in wind speed decreased wind erosion and the frequency of sandstorms. (5) The overall habitat quality in the TRHR was stable between 2000 and 2010, and the spatial pattern exhibited obvious heterogeneity. In some counties that included nature reserves, habitat quality was slightly higher in 2010 than in 2000, which reflected the effectiveness of the ecological restoration. Overall, the aforementioned ecosystem changes are the combined results of ecological restoration and climate change, and they are likely a local and temporary improvement, rather than a comprehensive and fundamental change. Therefore, more investments and efforts are needed to preserve natural ecosystems.

  14. Interactions between nutrients and toxicants in shallow freshwater model ecosystems

    NARCIS (Netherlands)

    Roessink, I.

    2008-01-01

    This thesis investigates the influence of the trophic status of a shallow freshwater system and/or the presence of persistent pollutants in the sediment on the fate and ecological effects of an insecticide and a fungicide/biocide. Additionally, this thesis aims to shed light on the influence of

  15. Ecological risk assessment for the terrestrial ecosystem under chronic radioactive pollution - Ecological risk assessment for the biota on regional radioactive waste storage

    Energy Technology Data Exchange (ETDEWEB)

    Lavrentyeva, G.V.; Synzynys, B.I.; Shoshina, R.R.; Mirzeabasov, O.A. [Obninsk Institute for Nuclear Power Engineering, branch of the National Research Nuclear University MEPhI, Department of Ecology, Studgorodok,1, 249040 Obninsk, Kaluga region (Russian Federation)

    2014-07-01

    Now the methods of ecological regulation of a radiation factor from risk assessment are developed poorly. The paper attempts to assess and forecast the terrestrial ecosystem conditions under chronic ionizing radiation by calculating the critical loads. The paper is aimed at developing a methodology to assess the ecological risk for a terrestrial ecosystem under chronic radioactive pollution in a biotope of a regional radioactive waste storage. Objects and Methods: Biotope monitoring of a radioactive waste storage makes clear that the radioecological situation in this territory is stipulated by technogenic {sup 90}Sr found in soil, ground water and biota. Terrestrial mollusks of a shrubby Snail type (Bradybaena fruticum) were chosen as reference species due to their activity to accumulate {sup 90}Sr in shells and the number of colony-forming soil units (CFU) as reference indices. The number of CFU was determined by inoculation of solid medium. Soil and mollusk samples have been collected at most representative sites identified in the previous studies. To assess {sup 90}Sr content in the samples collected, radiochemical separation was used with further radionuclide activity measurements by a 'BETA-01C' scintillation beta-ray spectrometer according to a standard procedure of {sup 90}Sr content assessment from beta-radiation of its daughter radionuclide {sup 90}Y. Ecological risk was calculated from analyzed critical loads using a 'dose-effect' dependence. Statistical data processing was realized with Excell 2007 and R software programs [R Development Core Team, 2010]. The software R was also used for GIS creation. Results and Discussion: A methodology of ecological risk assessment for the terrestrial ecosystem under chronic radioactive pollution of a biotope near a regional radioactive waste storage has been developed in terms of the critical environmental loads analyzed. It consists of five stages: determination of effect indicators and assessment

  16. A new quantitative model of ecological compensation based on ecosystem capital in Zhejiang Province, China*

    Science.gov (United States)

    Jin, Yan; Huang, Jing-feng; Peng, Dai-liang

    2009-01-01

    Ecological compensation is becoming one of key and multidiscipline issues in the field of resources and environmental management. Considering the change relation between gross domestic product (GDP) and ecological capital (EC) based on remote sensing estimation, we construct a new quantitative estimate model for ecological compensation, using county as study unit, and determine standard value so as to evaluate ecological compensation from 2001 to 2004 in Zhejiang Province, China. Spatial differences of the ecological compensation were significant among all the counties or districts. This model fills up the gap in the field of quantitative evaluation of regional ecological compensation and provides a feasible way to reconcile the conflicts among benefits in the economic, social, and ecological sectors. PMID:19353749

  17. Diversity-interaction modeling: estimating contributions of species identities and interactions to ecosystem function

    DEFF Research Database (Denmark)

    Kirwan, L; Connolly, J; Finn, J A

    2009-01-01

    to the roles of evenness, functional groups, and functional redundancy. These more parsimonious descriptions can be especially useful in identifying general diversity-function relationships in communities with large numbers of species. We provide an example of the application of the modeling framework......We develop a modeling framework that estimates the effects of species identity and diversity on ecosystem function and permits prediction of the diversity-function relationship across different types of community composition. Rather than just measure an overall effect of diversity, we separately....... These models describe community-level performance and thus do not require separate measurement of the performance of individual species. This flexible modeling approach can be tailored to test many hypotheses in biodiversity research and can suggest the interaction mechanisms that may be acting....

  18. Construction of Industrial Ecosystem of an Electric Company under Ecological Perspective

    Science.gov (United States)

    Li, Xin; Zhang, Yuan; Wu, Han

    2018-01-01

    Be confronted with more and more fierce competition environment, only by constantly integrating, constructing and restructuring internal and external resources as well as capabilities can enterprises adapt themselves to the rapidly changing environment and maintain the advantages of sustained competition. Business competition has changed from product competition of single enterprise to competition of bussiness ecosystem. Therefore, how to build a business system is the key to win competition. This paper draws lessons from business ecosystem and industrial ecosystem concept and takes the subordinate industry company of a large enterprise as the research object. On the the basis of combing its characteristics and organizational structure, an industrial ecosystem is tired to constructed.

  19. Ecological concerns following Superstorm Sandy: stressor level and recreational activity levels affect perceptions of ecosystem.

    Science.gov (United States)

    Burger, Joanna

    2015-06-01

    Coastal habitats are vulnerable to storms, and with increasing urbanization, sea level rise, and storm frequency, some urban populations are at risk. This study examined perceptions of respondents in coastal and central New Jersey to Superstorm Sandy , including: 1) concerns about ecological resources and effects (open-ended question), 2) information sources for ecology of the coast (open-ended), and 3) ratings of a list of ecological services as a function of demographics, location (coastal, central Jersey), stressor level (power outages, high winds, flooding) and recreational rates. "Wildlife" and "fish" were the ecological concerns mentioned most often, while beaches and dunes were most often mentioned for environmental concerns. Television, radio, and web/internet were sources trusted for ecological information. The data indicate 1) stressor level was a better predictor of ratings of ecological services than geographical location, but days engaged in recreation contributed the most to variations in ratings, 2) ecological services were rated the highest by respondents with the highest stressor levels, and by those from the coast, compared to others, 3) Caucasians rated ecological services higher than all others, and 4) recreational rates were highest for coastal respondents, and ratings for ecological services increased with recreational rates. Only 20 % of respondents listed specific ecological services as one of their three most important environmental concerns. These data will be useful for increasing preparedness, enhancing educational strategies for shore protection, and providing managers and public policy makers with data essential to developing resiliency strategies.

  20. Benthic indicators to use in Ecological Quality classification of Mediterranean soft bottom marine ecosystems, including a new Biotic Index

    Directory of Open Access Journals (Sweden)

    N. SIMBOURA

    2002-12-01

    Full Text Available A general scheme for approaching the objective of Ecological Quality Status (EcoQ classification of zoobenthic marine ecosystems is presented. A system based on soft bottom benthic indicator species and related habitat types is suggested to be used for testing the typological definition of a given water body in the Mediterranean. Benthic indices including the Shannon-Wiener diversity index and the species richness are re-evaluated for use in classification. Ranges of values and of ecological quality categories are given for the diversity and species richness in different habitat types. A new biotic index (BENTIX is proposed based on the relative percentages of three ecological groups of species grouped according to their sensitivity or tolerance to disturbance factors and weighted proportionately to obtain a formula rendering a five step numerical scale of ecological quality classification. Its advantage against former biotic indices lies in the fact that it reduces the number of the ecological groups involved which makes it simpler and easier in its use. The Bentix index proposed is tested and validated with data from Greek and western Mediterranean ecosystems and examples are presented. Indicator species associated with specific habitat types and pollution indicator species, scored according to their degree of tolerance to pollution, are listed in a table. The Bentix index is compared and evaluated against the indices of diversity and species richness for use in classification. The advantages of the BENTIX index as a classification tool for ECoQ include independence from habitat type, sample size and taxonomic effort, high discriminative power and simplicity in its use which make it a robust, simple and effective tool for application in the Mediterranean Sea.

  1. EcoPrinciples Connect: A Pilot Project Matching Ecological Principles with Available Data to Promote Ecosystem-Based Management

    Science.gov (United States)

    Martone, R. G.; Erickson, A.; Mach, M.; Hale, T.; McGregor, A.; Prahler, E. E.; Foley, M.; Caldwell, M.; Hartge, E. H.

    2016-12-01

    Ocean and coastal practitioners work within existing financial constraints, jurisdictions, and legislative authorities to manage coastal and marine resources while seeking to promote and maintain a healthy and productive coastal economy. Fulfilling this mandate necessitates incorporation of best available science, including ecosystem-based management (EBM) into coastal and ocean management decisions. To do this, many agencies seek ways to apply lessons from ecological theory into their decision processes. However, making direct connections between science and management can be challenging, in part because there is no process for linking ecological principles (e.g., maintaining species diversity, habitat diversity, connectivity and populations of key species) with available data. Here we explore how incorporating emerging data and methods into resource management at a local scale can improve the overall health of our coastal and marine ecosystems. We introduce a new web-based interface, EcoPrinciples Connect, that links marine managers to scientific and geospatial information through the lens of these ecological principles, ultimately helping managers become more efficient, more consistent, and advance the integration of EBM. The EcoPrinciples Connect tool grew directly out of needs identified in response to a Center for Ocean Solutions reference guide, Incorporating Ecological Principles into California Ocean and Coastal Management: Examples from Practice. Here we illustrate how we have worked to translate the information in this guide into a co-developed, user-centric tool for agency staff. Specifically, we present a pilot project where we match publicly available data to the ecological principles for the California San Francisco Bay Conservation and Development Commission. We will share early lessons learned from pilot development and highlight opportunities for future transferability to an expanded group of practitioners.

  2. The influence of ecological processes on the accumulation of persistent organochlorines in aquatic ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Berglund, Olof

    1999-09-01

    Several ecological problems influences the fate, transport, and accumulation of persistent organochlorines (OCs) in aquatic ecosystems. In this thesis, I have focused on two processes, namely (i) the food chain bioaccumulation of OCs, and (ii) the trophic status of the aquatic system. To test the biomagnification theory, I investigated PCB concentrations in planktonic food chains in lakes. The concentrations of PCB on a lipid basis did not increase with increasing trophic level. Hence, I could give no support to the theory of biomagnification. Instead, lipid content explained most of the variation in PCB accumulation in these food chains. PCBs were differentially fractionated in the food chains, the relative amount of high molecular weight PCBs increased with increasing trophic level, indicating congener specific differences in either the accumulation or the elimination of PCBs at the different trophic levels. In another study, I investigated the relationship between OC concentrations and trophic level, measured as {delta}{sup 15}N, in a specific predatory fish population. The dry weight OC concentrations and {delta}{sup 15}N were related, indicating effects of prey choice on the OC accumulation. However, here also, lipid content explained the major part of the variation in OC concentrations, independent of trophic level (e. g. {delta}{sup 15}N). I investigated the effects of trophic status, measured as Tot-P concentration in water, on the concentrations of OCs in water, planktonic food chains and sediment in lakes. The dry weight concentrations of PCBs in phytoplankton were negatively related to the trophic status of the lakes. However, this relationship was explained by the decreasing lipid content of phytoplankton with lake trophic status. The phytoplankton in eutrophic lakes had lower lipid content than phytoplankton in oligotrophic lakes, possibly due to inter- and intraspecific differences in lipid content due to nutrient stress. The sediment accumulation and

  3. Transforming "Ecosystem" from a Scientific Concept into a Teachable Topic: Philosophy and History of Ecology Informs Science Textbook Analysis

    Science.gov (United States)

    Schizas, Dimitrios; Papatheodorou, Efimia; Stamou, George

    2017-04-01

    This study conducts a textbook analysis in the frame of the following working hypothesis: The transformation of scientific knowledge into school knowledge is expected to reproduce the problems encountered with the scientific knowledge itself or generate additional problems, which may both induce misconceptions in textbook users. Specifically, we describe four epistemological problems associated with how the concept of "ecosystem" is elaborated within ecological science and we examine how each problem is reproduced in the biology textbook utilized by Greek students in the 12th grade and the resulting teacher and student misunderstandings that may occur. Our research demonstrates that the authors of the textbook address these problems by appealing simultaneously to holistic and reductionist ideas. This results in a meaningless and confused depiction of "ecosystem" and may provoke many serious misconceptions on the part of textbook users, for example, that an ecosystem is a system that can be applied to every set of interrelated ecological objects irrespective of the organizational level to which these entities belong or how these entities are related to each other. The implications of these phenomena for science education research are discussed from a perspective that stresses the role of background assumptions in the understanding of declarative knowledge.

  4. The Importance of Ecology-Based Nature Education Project in Terms of Nature Integration and Understanding the Human-Ecosystem Relationship

    Science.gov (United States)

    Meydan, Ali

    2011-01-01

    The aim of this project is to define the importance of 12-day ecology-based education training upon integration with nature and understanding the human-ecosystem relationship. In accordance with this purpose, there has been collected some survey data interviewing with the participants of "Lake Beysehir National Park and Ecology-based Nature…

  5. Predation and Ecology in Deep-Time: How Modern Marine Ecosystems Develop and Deteriorate

    Science.gov (United States)

    Tackett, L.

    2017-12-01

    Anti-predator adaptations in shelly prey and specialized feeding-capture structures in predators can be observed nearly everywhere in modern oceans. The conditions in which these adaptive "arms-races" between predators and prey developed in the oceans can yield important insights to predict how these relationships are affected by environmental change. However, in the fossil record it can be difficult to determine if an adaptation in a shelly animal is related to predation, or some other factor, such as competition for nutrients or space. To address (1) the problem of interpreting the function of shelly invertebrate adaptations, and (2) to identify environmental factors in the development of modern predator-prey interactions, I carefully study the relative abundances of shelly prey animals and microfossil remains of their predators in marine sediments. In the Late Triassic (220-204 million years ago), a dramatic paleoecological shift occurred among shelly marine animals—immobile surface-dwelling animals that had been abundant in the oceans for 300 million years became rare, and were replaced by burrowing clams, swimming scallops, cementing oysters, and many other new taxa with surprising adaptations. This proliferation of adaptive strategies seems to be synchronous with the appearance of many predator taxa specialized for shell-crushing that mainly moved along the seafloor. To test this hypothesis, I examine microfossils of these predators in the sediments containing macrofossils of their shelly prey, to find teeth or claw features that can exhibit specializations for shell-crushing or other predation modes. With the development of this very modern system of predator-prey interactions, we can better understand how these food-webs were disrupted by climatic perturbations later in the Triassic, and make meaningful comparisons to modern ocean ecosystems.

  6. Biocultural Ecology: Exploring the Social Construction of the Southern Appalachain Ecosystem

    Science.gov (United States)

    David P. Robertson; R. Bruce Hull

    2003-01-01

    The idea of a Southern Appalachian Ecosystem is now so much a part of our everyday language that many of the people who talk, write, and make decisions about thc place are unaware of the long and complicated history behind the idea. One primary purpose of this case study was to demonstrate how the Southern Appalachian Ecosystem has been socially constructed and reified...

  7. An assessment of long term ecosystem research activities across European socio-ecological gradients

    NARCIS (Netherlands)

    Metzger, M.J.; Bunce, R.G.H.; Eupen, van M.; Mirtl, M.

    2010-01-01

    Integration of European long term ecosystem research (LTER) would provide important support for the management of the pan-European environment and ecosystems, as well as international policy commitments. This does require appropriate coverage of Europe and standardised frameworks and research

  8. Unsuitability of TAC management within an ecosystem approach to fisheries: An ecological perspective

    NARCIS (Netherlands)

    Reiss, H.; Greenstreet, S.P.R.; Robinson, L.; Ehrich, S.; Jorgensen, L.L.; Piet, G.J.; Wolff, W.J.

    2010-01-01

    Fisheries management in European waters is gradually moving from a single-species perspective towards a more holistic ecosystem approach to management (EAM), acknowledging the need to take all ecosystem components into account. Prerequisite within an EAM is the need for management processes that

  9. Connecting Social Networks with Ecosystem Services for Watershed Governance: a Social-Ecological Network Perspective Highlights the Critical Role of Bridging Organizations

    Directory of Open Access Journals (Sweden)

    Kaitlyn J. Rathwell

    2012-06-01

    Full Text Available In many densely settled agricultural watersheds, water quality is a point of conflict between amenity and agricultural activities because of the varied demands and impacts on shared water resources. Successful governance of these watersheds requires coordination among different activities. Recent research has highlighted the role that social networks between management entities can play to facilitate cross-scale interaction in watershed governance. For example, bridging organizations can be positioned in social networks to bridge local initiatives done by single municipalities across whole watersheds. To better understand the role of social networks in social-ecological system dynamics, we combine a social network analysis of the water quality management networks held by local governments with a social-ecological analysis of variation in water management and ecosystem services across the Montérégie, an agricultural landscape near Montréal, Québec, Canada. We analyze municipal water management networks by using one-mode networks to represent direct collaboration between municipalities, and two-mode networks to capture how bridging organizations indirectly connect municipalities. We find that municipalities do not collaborate directly with one another but instead are connected via bridging organizations that span the water quality management network. We also discovered that more connected municipalities engaged in more water management activities. However, bridging organizations preferentially connected with municipalities that used more tourism related ecosystem services rather than those that used more agricultural ecosystem services. Many agricultural municipalities were relatively isolated, despite being the main producers of water quality problems. In combination, these findings suggest that further strengthening the water management network in the Montérégie will contribute to improving water quality in the region. However, such

  10. Aspects of elephant behavior, ecology, and interactions with humans

    Science.gov (United States)

    O'Connell, Caitlin Elizabeth

    This dissertation is comprised of two chapters relating to the acoustic behavior of elephants, their surrounding ecology and interactions with humans. The first chapter investigates the seismic aspects of Asian elephant (Elephus maximus) acoustic communication. The second chapter is comprised of a synthesis of two separate studies conducted on the African elephant (Loxodonta africana) in Namibia, both in Etosha National Park and the Caprivi region. The two studies were combined and published in Biological Conservation as one large study on aspects of the economic and social impacts of elephant/human conflict and experiments conducted to reduce conflict. In chapter one, seismic and acoustic data were recorded simultaneously from Asian elephants during periods of vocalizations and locomotion. Acoustic and seismic signals from rumbles were highly correlated at near and far distances and were in phase near the elephant and were out of phase at an increased distance from the elephant. Data analyses indicated that elephant generated signals associated with rumbles and "foot stomps" propagated at different velocities in the two media, the acoustic signals traveling at 309 m/s and the seismic signals at 248--264 m/s. Both types of signals had predominant frequencies in the range of 20 Hz. Seismic signal amplitudes considerably above background noise were recorded at 40 m from the generating elephants for both the rumble and the stomp. Seismic propagation models suggest that seismic waveforms from vocalizations are potentially detectable by instruments at distances of up to 16 km, and up to 32 km for locomotion generated signals. Thus, if detectable by elephants, these seismic signals could be useful for long distance communication. In chapter two, the economic impact of elephants, Loxodonta africana , and predators, particularly lions, Panthera leo, on rural agriculturists in the Kwando region of the East Caprivi, Namibia was assessed from the years 1991 to 1995. Elephants

  11. Species-environment interactions changed by introduced herbivores in an oceanic high-mountain ecosystem.

    Science.gov (United States)

    Seguí, Jaume; López-Darias, Marta; Pérez, Antonio J; Nogales, Manuel; Traveset, Anna

    2017-01-05

    Summit areas of oceanic islands constitute some of the most isolated ecosystems on earth, highly vulnerable to climate change and introduced species. Within the unique high-elevation communities of Tenerife (Canary Islands), reproductive success and thus long-term survival of species may depend on environmental suitability as well as threat by introduced herbivores. By experimentally modifying the endemic and vulnerable species Viola cheiranthifolia along its entire altitudinal occurrence range, we studied plant performance, autofertility, pollen limitation and visitation rate and the interactive effect of grazing by non-native rabbits on them. We assessed the grazing effects by recording (1) the proportion of consumed plants and flowers along the gradient, (2) comparing fitness traits of herbivore-excluded plants along the gradient, and (3) comparing fitness traits, autofertility and pollen limitation between plants excluded from herbivores with unexcluded plants at the same locality. Our results showed that V. cheiranthifolia performance is mainly affected by inter-annual and microhabitat variability along the gradient, especially in the lowest edge. Despite the increasingly adverse environmental conditions, the plant showed no pollen limitation with elevation, which is attributed to the increase in autofertility levels (≥ 50% of reproductive output) and decrease in competition for pollinators at higher elevations. Plant fitness is, however, extremely reduced owing to the presence of non-native rabbits in the area (consuming more than 75% of the individuals in some localities), which in turn change plant trait-environment interactions along the gradient. Taken together, these findings indicate that the elevational variation found on plant performance results from the combined action of non-native rabbits with the microhabitat variability, exerting intricate ecological influences that threaten the survival of this violet species. Published by Oxford University

  12. Hyperspectral remote sensing and long term monitoring reveal watershed-estuary ecosystem interactions

    Science.gov (United States)

    Hestir, E. L.; Schoellhamer, D. H.; Santos, M. J.; Greenberg, J. A.; Morgan-King, T.; Khanna, S.; Ustin, S.

    2016-02-01

    Estuarine ecosystems and their biogeochemical processes are extremely vulnerable to climate and environmental changes, and are threatened by sea level rise and upstream activities such as land use/land cover and hydrological changes. Despite the recognized threat to estuaries, most aspects of how change will affect estuaries are not well understood due to the poorly resolved understanding of the complex physical, chemical and biological processes and their interactions in estuarine systems. Remote sensing technologies such as high spectral resolution optical systems enable measurements of key environmental parameters needed to establish baseline conditions and improve modeling efforts. The San Francisco Bay-Delta is a highly modified estuary system in a state of ecological crisis due to the numerous threats to its sustainability. In this study, we used a combination of hyperspectral remote sensing and long-term in situ monitoring records to investigate how water clarity has been responding to extreme climatic events, anthropogenic watershed disturbances, and submerged aquatic vegetation (SAV) invasions. From the long-term turbidity monitoring record, we found that water clarity underwent significant increasing step changes associated with sediment depletion and El Nino-extreme run-off events. Hyperspectral remote sensing data revealed that invasive submerged aquatic pant species have facultative C3 and C4-like photosynthetic pathways that give them a competitive advantage under the changing water clarity conditions of the Bay-Delta system. We postulate that this adaptation facilitated the rapid expansion of SAV following the significant step changes in increasing water clarity caused by watershed disturbances and the 1982-1983 El Nino events. Using SAV maps from hyperspectral remote sensing, we estimate that SAV-water clarity feedbacks were responsible for 20-70% of the increasing water clarity trend in the Bay-Delta. Ongoing and future developments in airborne and

  13. Interactive visual analysis promotes exploration of long-term ecological data

    Science.gov (United States)

    T.N. Pham; J.A. Jones; R. Metoyer; F.J. Swanson; R.J. Pabst

    2013-01-01

    Long-term ecological data are crucial in helping ecologists understand ecosystem function and environmental change. Nevertheless, these kinds of data sets are difficult to analyze because they are usually large, multivariate, and spatiotemporal. Although existing analysis tools such as statistical methods and spreadsheet software permit rigorous tests of pre-conceived...

  14. Towards an Ecological Inquiry in Child-Computer Interaction

    DEFF Research Database (Denmark)

    Smith, Rachel Charlotte; Iversen, Ole Sejer; Hjermitslev, Thomas

    2013-01-01

    The paper introduces an Ecological Inquiry as a methodological approach for designing technology with children. The inquiry is based on the ‘ecological turn’ in HCI, Ubiquitous Computing and Participatory Design that shift the emphasis of design from technological artifacts to entire use ecologies...... into which technologies are integrated. Our Ecological Inquiry extends Cooperative Inquiry in three directions: from understanding to emergence of social practices and meanings, from design of artifacts to hybrid environments, and from a focus on technology to appropriations through design and use. We...... exemplify our approach in a case study in which we designed social technologies for hybrid learning environments with children in two schools, and discuss how an Ecological Inquiry can inform existing approaches in CCI....

  15. Better BAT to Bolster Ecosystem Resilience : Operationalizing Ecological Governance through the Concept of Best Available Techniques

    NARCIS (Netherlands)

    Giljam, Renske A.

    This article examines to what extent ecological governance can be implemented by extending the concept of Best Available Techniques (BAT) at the European Union level. It therefore firstly analyses what ecological governance would require and what this implies for employing the use of BAT. The

  16. Land-use change in Indian tropical agro-ecosystems: eco-energy estimation for socio-ecological sustainability.

    Science.gov (United States)

    Nautiyal, Sunil; Kaechele, Harald; Umesh Babu, M S; Tikhile, Pavan; Baksi, Sangeeta

    2017-04-01

    This study was carried out to understand the ecological and economic sustainability of floriculture and other main crops in Indian agro-ecosystems. The cultivation practices of four major flower crops, namely Jasminum multiflorum, Crossandra infundibuliformis, Chrysanthemum and Tagetes erecta, were studied in detail. The production cost of flowers in terms of energy was calculated to be 99,622-135,996 compared to 27,681-69,133 MJ ha -1 for the main crops, namely Oryza sativa, Eleusine coracana, Zea mays and Sorghum bicolor. The highest-energy input amongst the crops was recorded for Z. mays (69,133 MJ ha -1 ) as this is a resource-demanding crop. However, flower cultivation requires approximately twice the energy required for the cultivation of Z. mays. In terms of both energy and monetary inputs, flower cultivation needs two to three times the requirements of the main crops cultivated in the region. The monetary inputs for main crop cultivation were calculated to be ₹ 27,349 to ₹ 46,930 as compared to flower crops (₹ 62,540 to ₹ 144,355). Floriculture was found to be more efficient in monetary terms when compared to the main crops cultivated in the region. However, the energy efficiency of flower crops is lower than that of the main crops, and the energy output from flower cultivation was found to be declining in tropical agro-ecosystems in India. Amongst the various inputs, farmyard manure accounts for the highest proportion, and for its preparation, most of the raw material comes from the surrounding ecosystems. Thus, flower cultivation has a direct impact on the ecosystem resource flow. Therefore, keeping the economic and environmental sustainability in view, this study indicates that a more field-based research is required to frame appropriate policies for flower cultivation to achieve sustainable socio-ecological development.

  17. Effects of ionizing radiation upon natural populations and ecosystems. Final report. [Ecological perspectives in land use planning

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, J.F.

    1976-01-01

    Accomplishments throughout a 10-year period summarized include: a study of the effects of radiation from a ..gamma.. source on the ecology of the El Verde rain forest in Puerto Rico, with emphasis on the role of secondary succession in the recovery of forest ecosystems following irradiation; the effects of light and temperature on gaseous exchange in trees using /sup 14/CO/sub 2/ as a tracer in Palcourea; the nature of the sensitivity of pine trees to ionizing radiation and the possible synergistic effects of elevated ozone levels on radiosensitivity; the combined effects of radioactive and thermal effluents on plant communities of a swamp hardwood forest; and the development of a new conceptual approach to the evaluation of environmental quality, with emphasis on ecological perspectives in land use planning. (CH)

  18. Modelling of spatially complex human-ecosystem, rural-urban and rich-poor interactions

    CSIR Research Space (South Africa)

    Naude, AH

    2008-06-01

    Full Text Available The paper outlines the challenges of modelling and assessing spatially complex human-ecosystem interactions, and the need to simultaneously consider rural-urban and rich-poor interactions. The context for exploring these challenges is South Africa...

  19. Interactions between nutrients and organic micro-pollutants in shallow freshwater ecosystems

    NARCIS (Netherlands)

    Roessink, I.; Koelmans, A.A.; Brock, T.C.M.

    2008-01-01

    Effects of nutrients and toxicants in aquatic ecosystems may interact in several ways. Here, we (a) present an overview of reported mechanisms that may play a role in these interactions, and (b) compare these reported mechanisms against the results of a suite of experiments performed with organic

  20. Assessing the potential to restore historic grazing ecosystems with tortoise ecological replacements.

    Science.gov (United States)

    Griffiths, Christine J; Zuël, Nicolas; Jones, Carl G; Ahamud, Zairabee; Harris, Stephen

    2013-08-01

    The extinction of large herbivores, often keystone species, can dramatically modify plant communities and impose key biotic thresholds that may prevent an ecosystem returning to its previous state and threaten native biodiversity. A potentially innovative, yet controversial, landscape-based long-term restoration approach is to replace missing plant-herbivore interactions with non-native herbivores. Aldabran giant (Aldabrachelys gigantea) and Madagascan radiated (Astrochelys radiata) tortoises, taxonomically and functionally similar to the extinct Mauritian giant tortoises (Cylindraspis spp.), were introduced to Round Island, Mauritius, in 2007 to control the non-native plants that were threatening persistence of native species. We monitored the response of the plant community to tortoise grazing for 11 months in enclosures before the tortoises were released and, compared the cost of using tortoises as weeders with the cost of using manual labor. At the end of this period, plant biomass; vegetation height and cover; and adult, seedling, flower, and seed abundance were 3-136 times greater in adjacent control plots than in the tortoise enclosures. After their release, the free-roaming tortoises grazed on most non-native plants and significantly reduced vegetation cover, height, and seed production, reflecting findings from the enclosure study. The tortoises generally did not eat native species, although they consumed those native species that increased in abundance following the eradication of mammalian herbivores. Our results suggest that introduced non-native tortoises are a more cost-effective approach to control non-native vegetation than manual weeding. Numerous long-term outcomes (e.g., change in species composition and soil seed bank) are possible following tortoise releases. Monitoring and adaptive management are needed to ensure that the replacement herbivores promote the recovery of native plants. © 2013 Society for Conservation Biology.

  1. Eco-logical : an ecosystem approach to developing transportation infrastructure projects in a changing environment

    Science.gov (United States)

    2009-09-13

    The development of infrastructure facilities can negatively impact critical habitat and essential ecosystems. There are a variety of techniques available to avoid, minimize, and mitigate negative impacts of existing infrastructure as well as future i...

  2. Economic impact of ecosystem services provided by ecologically sustainable roadside right of way vegetation management practices.

    Science.gov (United States)

    2014-03-01

    The economic value of runoff prevention, carbon sequestration, pollination and other insect services, air quality, : invasive species resistance, and aesthetics was estimated for Floridas State Highway System roadside right-of-way (ROW) ecosystem ...

  3. Historical and projected carbon balance of mature black spruce ecosystems across north america: The role of carbon-nitrogen interactions

    Science.gov (United States)

    Clein, Joy S.; McGuire, A.D.; Zhang, X.; Kicklighter, D.W.; Melillo, J.M.; Wofsy, S.C.; Jarvis, P.G.; Massheder, J.M.

    2002-01-01

    The role of carbon (C) and nitrogen (N) interactions on sequestration of atmospheric CO2 in black spruce ecosystems across North America was evaluated with the Terrestrial Ecosystem Model (TEM) by applying parameterizations of the model in which C-N dynamics were either coupled or uncoupled. First, the performance of the parameterizations, which were developed for the dynamics of black spruce ecosystems at the Bonanza Creek Long-Term Ecological Research site in Alaska, were evaluated by simulating C dynamics at eddy correlation tower sites in the Boreal Ecosystem Atmosphere Study (BOREAS) for black spruce ecosystems in the northern study area (northern site) and the southern study area (southern site) with local climate data. We compared simulated monthly growing season (May to September) estimates of gross primary production (GPP), total ecosystem respiration (RESP), and net ecosystem production (NEP) from 1994 to 1997 to available field-based estimates at both sites. At the northern site, monthly growing season estimates of GPP and RESP for the coupled and uncoupled simulations were highly correlated with the field-based estimates (coupled: R2= 0.77, 0.88 for GPP and RESP; uncoupled: R2 = 0.67, 0.92 for GPP and RESP). Although the simulated seasonal pattern of NEP generally matched the field-based data, the correlations between field-based and simulated monthly growing season NEP were lower (R2 = 0.40, 0.00 for coupled and uncoupled simulations, respectively) in comparison to the correlations between field-based and simulated GPP and RESP. The annual NEP simulated by the coupled parameterization fell within the uncertainty of field-based estimates in two of three years. On the other hand, annual NEP simulated by the uncoupled parameterization only fell within the field-based uncertainty in one of three years. At the southern site, simulated NEP generally matched field-based NEP estimates, and the correlation between monthly growing season field-based and

  4. Ecological consequences of interactions between ants and honeydew-producing insects

    OpenAIRE

    Styrsky, John D; Eubanks, Micky D

    2006-01-01

    Interactions between ants and honeydew-producing hemipteran insects are abundant and widespread in arthropod food webs, yet their ecological consequences are very poorly known. Ant–hemipteran interactions have potentially broad ecological effects, because the presence of honeydew-producing hemipterans dramatically alters the abundance and predatory behaviour of ants on plants. We review several studies that investigate the consequences of ant–hemipteran interactions as ‘keystone interactions’...

  5. Recording of ecological half-lives of 90Sr and 137Cs in terrestrial and aquatic ecosystems

    International Nuclear Information System (INIS)

    Proehl, G.; Fiedler, I.; Ehlken, S.

    2004-01-01

    Within this project, the long-term behaviour of 90 Sr and 137 Cs in foods, feeds and a variety of environmental was analysed. The long-term behaviour is quantified by means of the ecological half-life which integrates all processes that cause a decrease of activity in a given medium as leaching, fixation and erosion. The following results were achieved: - For plant and animal food products, the ecological half-lives are in the range of 4 to 6 and 10 to 20 years for cesium and strontium respectively. The ecological half-lives for the period 1965 to 1985 are slightly shorter than those derived from monitoring measurements performed after 1987, due to the ongoing deposition in the post weapons' fallout period. - According to the German radioecological model that is applied during licensing of nuclear installations to assess radiation exposures to the general due to planned releases, the ecological half-lives for plant food products are 26 and 13 a for cesium and strontium respectively. In radioecological model that is used within the decision support system RODOS, the ecological half-lives are 8 years for Cesium and 14 years for strontium, which agrees well with the finding of this study. - For roe deer, deer, wild boar and forest plants (including mushrooms), under Middle European conditions, the ecological half-lives are about 12 years for cesium. However, in Ukraine, the cesium levels in forest products are much more persistent; in some cases the decrease of activity is only caused by the radioactive decay. - The variability of the long-term behaviour of 137Cs and 90Sr in freshwater ecosystems is much more pronounced than for terrestrial systems. It depends strongly on the sitespecific characteristics. The observed ecological half-lives for 137Cs and 90Sr cover a wide range from several days to several years. - The data to derive ecological half-lives of cesium in soil is relatively poor. For the upper soil layer of 0-10 cm, ecological half-lives were derived

  6. Symmetry of interactions rules in incompletely connected random replicator ecosystems.

    Science.gov (United States)

    Kärenlampi, Petri P

    2014-06-01

    The evolution of an incompletely connected system of species with speciation and extinction is investigated in terms of random replicators. It is found that evolving random replicator systems with speciation do become large and complex, depending on speciation parameters. Antisymmetric interactions result in large systems, whereas systems with symmetric interactions remain small. A co-dominating feature is within-species interaction pressure: large within-species interaction increases species diversity. Average fitness evolves in all systems, however symmetry and connectivity evolve in small systems only. Newcomers get extinct almost immediately in symmetric systems. The distribution in species lifetimes is determined for antisymmetric systems. The replicator systems investigated do not show any sign of self-organized criticality. The generalized Lotka-Volterra system is shown to be a tedious way of implementing the replicator system.

  7. How ecological restoration alters ecosystem services: an analysis of carbon sequestration in China's Loess Plateau.

    Science.gov (United States)

    Feng, Xiaoming; Fu, Bojie; Lu, Nan; Zeng, Yuan; Wu, Bingfang

    2013-10-03

    Restoring disturbed and over-exploited ecosystems is important to mitigate human pressures on natural ecosystems. China has launched an ambitious national ecosystem restoration program called Grain to Green Program (GTGP) over the last decade. By using remote sensing techniques and ecosystem modelling, we quantitatively evaluated the changes in ecosystem carbon sequestration since China's GTGP program during period of 2000-2008. It was found the NPP and NEP in this region had steadily increased after the initiative of the GTGP program, and a total of 96.1 Tg of additional carbon had been sequestered during that period. Changes in soil carbon storage were lagged behind and thus insignificant over the period, but was expected to follow in the coming decades. As a result, the Loess Plateau ecosystem had shifted from a net carbon source in 2000 to a net carbon sink in 2008. The carbon sequestration efficiency was constrained by precipitation, and appropriate choices of restoration types (trees, shrubs, and grasses) in accordance to local climate are critical for achieving the best benefit/cost efficiency.

  8. Ecological half-lives in the Faeroe Islands' and in Danish agricultural ecosystems

    International Nuclear Information System (INIS)

    Aarkrog, A.

    1992-01-01

    It is important to be conversant with the ecological halving times when determining doses from radioactive pollution of the environment. This subject is elaborated and dose calculations and transfer factors are dealt with. It is stated that Sr-90 shows a longer ecological halving time then Cs-137. Cs-137 from global fallout has a longer halving time than that originating from the Chernobyl accident. Unexpectedly, global fallout in Danish food products has a longer ecological halving time than is found in products from the Faroe Islands. These factors are discussed further. (AB)

  9. Ecology and Distribution of Copepods from the Salt Pan Ecosystems of Mumbai, West Coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Stephen, R.; Jayalakshmy, K.V.; NaveenKumar, K.R.; Nair, V.R.

    Ecology, distribution and diversity of Copepod collected from two salt pans of Mumbai, India, are presented. Copepods, the mai zooplankton components, consisted mainly of Bestiolina similis, Acartia southwelli, Oithona sp., O. similis, O. hebes...

  10. Genomics meets applied ecology : Characterizing habitat quality for sloths in a tropical agro-ecosystem

    NARCIS (Netherlands)

    Fountain, Emily D; Kang, Jung Koo; Tempel, Douglas J; Palsbøll, Per J; Pauli, Jonathan N; Peery, M Zachariah

    Understanding how habitat quality in heterogeneous landscapes governs the distribution and fitness of individuals is a fundamental aspect of ecology. While mean individual fitness is generally considered a key to assessing habitat quality, a comprehensive understanding of habitat quality in

  11. The Ecology of Parasite-Host Interactions at Montezuma Well National Monument, Arizona - Appreciating the Importance of Parasites

    Science.gov (United States)

    O'Brien, Chris; van Riper, Charles

    2009-01-01

    Although parasites play important ecological roles through the direct interactions they have with their hosts, historically that fact has been underappreciated. Today, scientists have a growing appreciation of the scope of such impacts. Parasites have been reported to dominate food webs, alter predator-prey relationships, act as ecosystem engineers, and alter community structure. In spite of this growing awareness in the scientific community, parasites are still often neglected in the consideration of the management and conservation of resources and ecosystems. Given that at least half of the organisms on earth are probably parasitic, it should be evident that the ecological functions of parasites warrant greater attention. In this report, we explore different aspects of parasite-host relationships found at a desert spring pond within Montezuma Well National Monument, Arizona. In three separate but related chapters, we explore interactions between a novel amphipod host and two parasites. First, we identify how host behavior responds to this association and how this association affects interactions with both invertebrate non-host predators and a vertebrate host predator. Second, we look at the human dimension, investigating how human recreation can indirectly affect patterns of disease by altering patterns of vertebrate host space use. Finally - because parasites and diseases are of increasing importance in the management of wildlife species, especially those that are imperiled or of management concern - the third chapter argues that research would benefit from increased attention to the statistical analysis of wildlife disease studies. This report also explores issues of statistical parasitology, providing information that may better inform those designing research projects and analyzing data from studies of wildlife disease. In investigating the nature of parasite-host interactions, the role that relationships play in ecological communities, and how human

  12. An ecological method to understand agricultural standardization in peach orchard ecosystems.

    Science.gov (United States)

    Wan, Nian-Feng; Zhang, Ming-Yi; Jiang, Jie-Xian; Ji, Xiang-Yun; Hao-Zhang

    2016-02-22

    While the worldwide standardization of agricultural production has been advocated and recommended, relatively little research has focused on the ecological significance of such a shift. The ecological concerns stemming from the standardization of agricultural production may require new methodology. In this study, we concentrated on how ecological two-sidedness and ecological processes affect the standardization of agricultural production which was divided into three phrases (pre-, mid- and post-production), considering both the positive and negative effects of agricultural processes. We constructed evaluation indicator systems for the pre-, mid- and post-production phases and here we presented a Standardization of Green Production Index (SGPI) based on the Full Permutation Polygon Synthetic Indicator (FPPSI) method which we used to assess the superiority of three methods of standardized production for peaches. The values of SGPI for pre-, mid- and post-production were 0.121 (Level IV, "Excellent" standard), 0.379 (Level III, "Good" standard), and 0.769 × 10(-2) (Level IV, "Excellent" standard), respectively. Here we aimed to explore the integrated application of ecological two-sidedness and ecological process in agricultural production. Our results are of use to decision-makers and ecologists focusing on eco-agriculture and those farmers who hope to implement standardized agricultural production practices.

  13. Loss of an ecological baseline through the eradication of oyster reefs from coastal ecosystems and human memory.

    Science.gov (United States)

    Alleway, Heidi K; Connell, Sean D

    2015-06-01

    Oyster reefs form over extensive areas and the diversity and productivity of sheltered coasts depend on them. Due to the relatively recent population growth of coastal settlements in Australia, we were able to evaluate the collapse and extirpation of native oyster reefs (Ostrea angasi) over the course of a commercial fishery. We used historical records to quantify commercial catch of O. angasi in southern Australia from early colonization, around 1836, to some of the last recorded catches in 1944 and used our estimates of catch and effort to map their past distribution and assess oyster abundance over 180 years. Significant declines in catch and effort occurred from 1886 to 1946 and no native oyster reefs occur today, but historically oyster reefs extended across more than 1,500 km of coastline. That oyster reefs were characteristic of much of the coastline of South Australia from 1836 to 1910 appears not to be known because there is no contemporary consideration of their ecological and economic value. Based on the concept of a shifted baseline, we consider this contemporary state to reflect a collective, intergenerational amnesia. Our model of generational amnesia accounts for differences in intergenerational expectations of food, economic value, and ecosystem services of nearshore areas. An ecological system that once surrounded much of the coast and possibly the past presence of oyster reefs altogether may be forgotten and could not only undermine progress towards their recovery, but also reduce our expectations of these coastal ecosystems. © 2015 Society for Conservation Biology.

  14. Coastal livelihood transitions under globalization with implications for trans-ecosystem interactions.

    Science.gov (United States)

    Kramer, Daniel B; Stevens, Kara; Williams, Nicholas E; Sistla, Seeta A; Roddy, Adam B; Urquhart, Gerald R

    2017-01-01

    Anthropogenic threats to natural systems can be exacerbated due to connectivity between marine, freshwater, and terrestrial ecosystems, complicating the already daunting task of governance across the land-sea interface. Globalization, including new access to markets, can change social-ecological, land-sea linkages via livelihood responses and adaptations by local people. As a first step in understanding these trans-ecosystem effects, we examined exit and entry decisions of artisanal fishers and smallholder farmers on the rapidly globalizing Caribbean coast of Nicaragua. We found that exit and entry decisions demonstrated clear temporal and spatial patterns and that these decisions differed by livelihood. In addition to household characteristics, livelihood exit and entry decisions were strongly affected by new access to regional and global markets. The natural resource implications of these livelihood decisions are potentially profound as they provide novel linkages and spatially-explicit feedbacks between terrestrial and marine ecosystems. Our findings support the need for more scientific inquiry in understanding trans-ecosystem tradeoffs due to linked-livelihood transitions as well as the need for a trans-ecosystem approach to natural resource management and development policy in rapidly changing coastal regions.

  15. Coastal livelihood transitions under globalization with implications for trans-ecosystem interactions.

    Directory of Open Access Journals (Sweden)

    Daniel B Kramer

    Full Text Available Anthropogenic threats to natural systems can be exacerbated due to connectivity between marine, freshwater, and terrestrial ecosystems, complicating the already daunting task of governance across the land-sea interface. Globalization, including new access to markets, can change social-ecological, land-sea linkages via livelihood responses and adaptations by local people. As a first step in understanding these trans-ecosystem effects, we examined exit and entry decisions of artisanal fishers and smallholder farmers on the rapidly globalizing Caribbean coast of Nicaragua. We found that exit and entry decisions demonstrated clear temporal and spatial patterns and that these decisions differed by livelihood. In addition to household characteristics, livelihood exit and entry decisions were strongly affected by new access to regional and global markets. The natural resource implications of these livelihood decisions are potentially profound as they provide novel linkages and spatially-explicit feedbacks between terrestrial and marine ecosystems. Our findings support the need for more scientific inquiry in understanding trans-ecosystem tradeoffs due to linked-livelihood transitions as well as the need for a trans-ecosystem approach to natural resource management and development policy in rapidly changing coastal regions.

  16. Towards More Effective Water Quality Governance: A Review of Social-Economic, Legal and Ecological Perspectives and Their Interactions

    Directory of Open Access Journals (Sweden)

    Susanne Wuijts

    2018-03-01

    Full Text Available In this article, social-economic, legal and ecological perspectives on effectiveness of water quality governance and their interactions have been studied. Worldwide, authorities are facing the challenge of restoring and preserving aquatic ecosystems in accordance with the United Nations Sustainable Development Goals (SDG 6. Over the last few decades, governance approaches have often been used to realise these ambitions. To date, scholars have identified that it is difficult to relate governance approaches to water quality improvement and have offered several different explanations for this. Combined with a targeted conceptualisation of the perspectives and their interactions, the systematic literature review demonstrates the gap that exists in the current understanding of these interactions and what their effects are on water quality improvement, especially in regard to the identification of ecological issues and their boundary conditions for the legal framework and the development of measures and follow-up. The review also reveals that the scientific debate is focused on the planning rather than implementation phase. A step forward can be made by supplementing existing analytical frameworks by the interactions between the different perspectives, especially those related to problem definition and the development and realisation of measures.

  17. Decadal-scale ecosystem memory reveals interactive effects of drought and insect defoliation on boreal forest productivity

    Science.gov (United States)

    Itter, M.; D'Orangeville, L.; Dawson, A.; Kneeshaw, D.; Finley, A. O.

    2017-12-01

    Drought and insect defoliation have lasting impacts on the dynamics of the boreal forest. Impacts are expected to worsen under global climate change as hotter, drier conditions forecast for much of the boreal increase the frequency and severity of drought and defoliation events. Contemporary ecological theory predicts physiological feedbacks in tree responses to drought and defoliation amplify impacts potentially causing large-scale productivity losses and forest mortality. Quantifying the interactive impacts of drought and insect defoliation on regional forest health is difficult given delayed and persistent responses to disturbance events. We developed a Bayesian hierarchical model to estimate forest growth responses to interactions between drought and insect defoliation by species and size class. Delayed and persistent responses to past drought and defoliation were quantified using empirical memory functions allowing for improved detection of interactions. The model was applied to tree-ring data from stands in Western (Alberta) and Eastern (Québec) regions of the Canadian boreal forest with different species compositions, disturbance regimes, and regional climates. Western stands experience chronic water deficit and forest tent caterpillar (FTC) defoliation; Eastern stands experience irregular water deficit and spruce budworm (SBW) defoliation. Ecosystem memory to past water deficit peaked in the year previous to growth and decayed to zero within 5 (West) to 8 (East) years; memory to past defoliation ranged from 8 (West) to 12 (East) years. The drier regional climate and faster FTC defoliation dynamics (compared to SBW) likely contribute to shorter ecosystem memory in the West. Drought and defoliation had the largest negative impact on large-diameter, host tree growth. Surprisingly, a positive interaction was observed between drought and defoliation for large-diameter, non-host trees likely due to reduced stand-level competition for water. Results highlight the

  18. Putative bacterial interactions from metagenomic knowledge with an integrative systems ecology approach.

    Science.gov (United States)

    Bordron, Philippe; Latorre, Mauricio; Cortés, Maria-Paz; González, Mauricio; Thiele, Sven; Siegel, Anne; Maass, Alejandro; Eveillard, Damien

    2016-02-01

    Following the trend of studies that investigate microbial ecosystems using different metagenomic techniques, we propose a new integrative systems ecology approach that aims to decipher functional roles within a consortium through the integration of genomic and metabolic knowledge at genome scale. For the sake of application, using public genomes of five bacterial strains involved in copper bioleaching: Acidiphilium cryptum, Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, Leptospirillum ferriphilum, and Sulfobacillus thermosulfidooxidans, we first reconstructed a global metabolic network. Next, using a parsimony assumption, we deciphered sets of genes, called Sets from Genome Segments (SGS), that (1) are close on their respective genomes, (2) take an active part in metabolic pathways and (3) whose associated metabolic reactions are also closely connected within metabolic networks. Overall, this SGS paradigm depicts genomic functional units that emphasize respective roles of bacterial strains to catalyze metabolic pathways and environmental processes. Our analysis suggested that only few functional metabolic genes are horizontally transferred within the consortium and that no single bacterial strain can accomplish by itself the whole copper bioleaching. The use of SGS pinpoints a functional compartmentalization among the investigated species and exhibits putative bacterial interactions necessary for promoting these pathways. © 2015 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  19. Microbial Interactions and the Ecology and Evolution of Hawaiian Drosophilidae

    Directory of Open Access Journals (Sweden)

    Timothy eO'Connor

    2014-12-01

    Full Text Available Adaptive radiations are characterized by an increased rate of speciation and expanded range of habitats and ecological niches exploited by those species. The Hawaiian Drosophilidae is a classic adaptive radiation; a single ancestral species colonized Hawaii approximately 25 million years ago and gave rise to two monophyletic lineages, the Hawaiian Drosophila and the genus Scaptomyza. The Hawaiian Drosophila are largely saprophagous and rely on approximately 40 endemic plant families and their associated microbes to complete development. Scaptomyza are even more diverse in host breadth. While many species of Scaptomyza utilize decomposing plant substrates, some species have evolved to become herbivores, parasites on spider egg masses, and exploit microbes on living plant tissue. Understanding the origin of the ecological diversity encompassed by these nearly 700 described species has been a challenge. The central role of microbes in drosophilid ecology suggests bacterial and fungal associates may have played a role in the diversification of the Hawaiian Drosophilidae. Here we synthesize recent ecological and microbial community data from the Hawaiian Drosophilidae to examine the forces that may have led to this adaptive radiation. We propose that the evolutionary success of the Hawaiian Drosophilidae is due to a combination of factors, including adaptation to novel ecological niches facilitated by microbes.

  20. Effects on parathion on the ecology of a eutrophic aquatic ecosystem: limnocorral experiment

    International Nuclear Information System (INIS)

    Gasith, A.; Perry, A.S.; Mozel, Y.; Albright, J.L.

    1983-01-01

    Repetitive exposure of a eutrophic fish pond ecosystem, enclosed in limnocorrals, to 30 ppb parathion resulted in elimination of the potentially dominant zooplankton species, Moina micrura. Consequently, the populations of the rotifers Brachionus and Asplanchna markedly increased. Changes in the zooplankton composition and abundance were followed by increased fluctuations in phytoplankton biomass, phytoplankton photosynthesis, plankton respiration and community metabolism. Similar responses to parathion treatment were observed in previous studies under fish pond conditions. In the presence of fish the effect of parathion on the ecosystem was generally less pronounced and not uniform. The collapse of the zooplankton community and the rapid changes in limnological conditions in the control (untreated) limnocorrals severely limited the duration of the experiment. The results suggest that under eutrophic conditions, small enclosures may be useful for evaluation of the effect of toxicants on the ecosystem only in short term experiments with short lived chemicals. (author)

  1. How sulfate-rich mine drainage affected aquatic ecosystem degradation in northeastern China, and potential ecological risk.

    Science.gov (United States)

    Zhao, Qian; Guo, Fen; Zhang, Yuan; Ma, Shuqin; Jia, Xiaobo; Meng, Wei

    2017-12-31

    Mining activity is an increasingly important stressor for freshwater ecosystems. However, the mechanism on how sulfate-rich mine drainage affects freshwater ecosystems is largely unknown, and its potential ecological risk has not been assessed so far. During 2009-2016, water and macroinvertebrate samples from 405 sample sites were collected along the mine drainage gradient from circum-neutral to alkaline waters in Hun-Tai River, Northeastern China. Results of linear regressions showed that sulfate-rich mine drainage was significantly positively correlated with the constituents typically derived from rock weathering (Ca 2+ , Mg 2+ and HCO 3 - +CO 3 2- ); the diversity of intolerant stream macroinvertebrates exhibited a steep decline along the gradient of sulfate-rich mine drainage. Meanwhile, stressor-response relationships between sulfate-rich mine drainage and macroinvertebrate communities were explored by two complementary statistical approaches in tandem (Threshold Indicator Taxa Analysis and the field-based method developed by USEPA). Results revealed that once stream sulfate concentrations in mine drainage exceeded 35mg/L, significant decline in the abundance of intolerant macroinvertebrate taxa occurred. An assessment of ecological risk posed by sulfate-rich mine drainage was conducted based on a tiered approach consisting of simple deterministic method (Hazard Quotient, HQ) to probabilistic method (Joint Probability Curve, JPC). Results indicated that sulfate-rich mine drainage posed a potential risk, and 64.62-84.88% of surface waters in Hun-Tai River exist serious risk while 5% threshold (HC 05 ) and 1% threshold (HC 01 ) were set up to protect macroinvertebrates, respectively. This study provided us a better understanding on the impacts of sulfate-rich mine drainage on freshwater ecosystems, and it would be helpful for future catchment management to protect streams from mining activity. Copyright © 2017. Published by Elsevier B.V.

  2. Mutualistic interactions drive ecological niche convergence in a diverse butterfly community.

    Science.gov (United States)

    Elias, Marianne; Gompert, Zachariah; Jiggins, Chris; Willmott, Keith

    2008-12-02

    Ecological communities are structured in part by evolutionary interactions among their members. A number of recent studies incorporating phylogenetics into community ecology have upheld the paradigm that competition drives ecological divergence among species of the same guild. However, the role of other interspecific interactions, in particular positive interactions such as mutualism, remains poorly explored. We characterized the ecological niche and inferred phylogenetic relationships among members of a diverse community of neotropical Müllerian mimetic butterflies. Müllerian mimicry is one of the best studied examples of mutualism, in which unpalatable species converge in wing pattern locally to advertize their toxicity to predators. We provide evidence that mutualistic interactions can drive convergence along multiple ecological axes, outweighing both phylogeny and competition in shaping community structure. Our findings imply that ecological communities are adaptively assembled to a much greater degree than commonly suspected. In addition, our results show that phenotype and ecology are strongly linked and support the idea that mimicry can cause ecological speciation through multiple cascading effects on species' biology.

  3. Mutualistic interactions drive ecological niche convergence in a diverse butterfly community.

    Directory of Open Access Journals (Sweden)

    Marianne Elias

    2008-12-01

    Full Text Available Ecological communities are structured in part by evolutionary interactions among their members. A number of recent studies incorporating phylogenetics into community ecology have upheld the paradigm that competition drives ecological divergence among species of the same guild. However, the role of other interspecific interactions, in particular positive interactions such as mutualism, remains poorly explored. We characterized the ecological niche and inferred phylogenetic relationships among members of a diverse community of neotropical Müllerian mimetic butterflies. Müllerian mimicry is one of the best studied examples of mutualism, in which unpalatable species converge in wing pattern locally to advertize their toxicity to predators. We provide evidence that mutualistic interactions can drive convergence along multiple ecological axes, outweighing both phylogeny and competition in shaping community structure. Our findings imply that ecological communities are adaptively assembled to a much greater degree than commonly suspected. In addition, our results show that phenotype and ecology are strongly linked and support the idea that mimicry can cause ecological speciation through multiple cascading effects on species' biology.

  4. Developing a framework for integrating turbulence measurements and modeling of ecosystem-atmosphere interactions

    Science.gov (United States)

    Markfort, C. D.

    2017-12-01

    Aquatic ecosystems are integrators of nutrient and carbon from their watersheds. The effects of climate change in many cases will enhance the rate of these inputs and change the thermodynamics within aquatic environments. It is unclear the extent these changes will have on water quality and carbon assimilation, but the drivers of these processes will be determined by the complex interactions at the land-water and air-water interfaces. For example, flow over and beneath wind-driven surface waves generate turbulence that plays an important role in aquatic ecology and biogeochemistry, exchange of gases such as oxygen and carbon dioxide, and it is important for the transfer of energy and controlling evaporation. Energy transferred from the atmosphere promotes the generation and maintenance of waves. A fraction of the energy is transferred to the surface mixed layer through the generation of turbulence. Energy is also transferred back to the atmosphere by waves. There is a need to quantify the details of the coupled boundary layers of the air-water system to better understand how turbulence plays a role in the interactions. We have developed capabilities to conduct field and laboratory experiments using eddy covariance on tall-towers and rafts, UAS platforms integrated with remote sensing, and detailed wind-wave measurements with time-resolved PIV in a new boundary layer wind-wave tunnel. We will show measurements of the detailed structure of the air and water boundary layers under varying wind and wave conditions in the newly developed IIHR Boundary-Layer Wind-Wave Tunnel. The facility combines a 30-m long recirculating water channel with an open-return boundary layer wind tunnel. A thick turbulent boundary layer is developed in the 1 m high air channel, over the water surface, allowing for the study of boundary layer turbulence interacting with a wind-driven wave field. Results will help interpret remote sensing, energy budget measurements, and turbulence transport

  5. Role of the noise on the transient dynamics of an ecosystem of interacting species

    Science.gov (United States)

    Spagnolo, B.; La Barbera, A.

    2002-11-01

    We analyze the transient dynamics of an ecosystem described by generalized Lotka-Volterra equations in the presence of a multiplicative noise and a random interaction parameter between the species. We consider specifically three cases: (i) two competing species, (ii) three interacting species (one predator-two preys), (iii) n-interacting species. The interaction parameter in case (i) is a stochastic process which obeys a stochastic differential equation. We find noise delayed extinction of one of two species, which is akin to the noise-enhanced stability phenomenon. Other two noise-induced effects found are temporal oscillations and spatial patterns of the two competing species. In case (ii) the noise induces correlated spatial patterns of the predator and of the two preys concentrations. Finally, in case (iii) we find the asymptotic behavior of the time average of the ith population when the ecosystem is composed of a great number of interacting species.

  6. Natural Length Scales of Ecological Systems: Applications at Community and Ecosystem Levels

    Directory of Open Access Journals (Sweden)

    Craig R. Johnson

    2009-06-01

    Full Text Available The characteristic, or natural, length scales of a spatially dynamic ecological landscape are the spatial scales at which the deterministic trends in the dynamic are most sharply in focus. Given recent development of techniques to determine the characteristic length scales (CLSs of real ecological systems, I explore the potential for using CLSs to address three important and vexing issues in applied ecology, viz. (i determining the optimum scales to monitor ecological systems, (ii interpreting change in ecological communities, and (iii ascertaining connectivity between species in complex ecologies. In summarizing the concept of characteristic length scales as system-level scaling thresholds, I emphasize that the primary CLS is, by definition, the optimum scale at which to monitor a system if the objective is to observe its deterministic dynamics at a system level. Using several different spatially explicit individual-based models, I then explore predictions of the underlying theory of CLSs in the context of interpreting change and ascertaining connectivity among species in ecological systems. Analysis of these models support predictions that systems with strongly fluctuating community structure, but an otherwise stable long-term dynamic defined by a stationary attractor, indicate an invariant length scale irrespective of community structure at the time of analysis, and irrespective of the species analyzed. In contrast, if changes in the underlying dynamic are forcibly induced, the shift in dynamics is reflected by a change in the primary length scale. Thus, consideration of the magnitude of the CLS through time enables distinguishing between circumstances where there are temporal changes in community structure but not in the long-term dynamic, from that where changes in community structure reflect some kind of fundamental shift in dynamics. In this context, CLSs emerge as a diagnostic tool to identify phase shifts to alternative stable states

  7. Ecological interactions of bark beetles with host trees

    Science.gov (United States)

    Certain species of bark beetles in the insect order Coleoptera, family Curculionidae (formerly Scolytidae) are keystone species in forest ecosystems. However, the tree-killing and woodboring bark and ambrosia beetles are also among the most damaging insects of forest products including lumber, paper...

  8. Diversity in a complex ecological network with two interaction types

    Czech Academy of Sciences Publication Activity Database

    Melián, C. J.; Bascompte, J.; Jordano, P.; Křivan, Vlastimil

    2009-01-01

    Roč. 118, č. 1 (2009), s. 122-130 ISSN 0030-1299 R&D Projects: GA AV ČR IAA100070601 Grant - others:University of California(US) DEB-0553768; The Spanish Ministry of Science and Technology (ES) REN2003-04774; The Spanish Ministry of Science and Technology (ES) REN2003-00273 Institutional research plan: CEZ:AV0Z50070508 Keywords : complex ecological network Subject RIV: EH - Ecology, Behaviour Impact factor: 3.147, year: 2009

  9. Ecosystems and climate interactions in the boreal zone of northern Eurasia

    International Nuclear Information System (INIS)

    Vygodskaya, N N; Groisman, P Ya; Tchebakova, N M; Kurbatova, J A; Panfyorov, O; Parfenova, E I; Sogachev, A F

    2007-01-01

    The climate system and terrestrial ecosystems interact as they change. In northern Eurasia these interactions are especially strong, span all spatial and timescales, and thus have become the subject of an international program: the Northern Eurasia Earth Science Partnership Initiative (NEESPI). Without trying to cover all areas of these interactions, this paper introduces three examples of the principal micrometeorological, mesometeorological and subcontinental feedbacks that control climate-terrestrial ecosystem interactions in the boreal zone of northern Eurasia. Positive and negative feedbacks of forest paludification, of windthrow, and of climate-forced displacement of vegetation zones are presented. Moreover the interplay of different scale feedbacks, the multi-faceted nature of ecosystems-climate interactions and their potential to affect the global Earth system are shown. It is concluded that, without a synergetic modeling approach that integrates all major feedbacks and relationships between terrestrial ecosystems and climate, reliable projections of environmental change in northern Eurasia are impossible, which will also bring into question the accuracy of global change projections

  10. Development and application of an interactive climate-ecosystem model system

    Institute of Scientific and Technical Information of China (English)

    CHEN Ming; D. Pollard

    2003-01-01

    A regional climate-ecosystem model system is developed in this study. It overcomes the weakness in traditional one-way coupling models and enables detailed description of interactive process between climate and natural ecosystem. It is applied to interaction study between monsoon climate and ecosystem in East Asia, with emphasis on future climate and ecosystem change scenario forced by doubled CO2. The climate tends to be warmer and wetter under doubled CO2 in Jianghuai and the Yangzi River valley, but it becomes warmer and drier in inland areas of northern and northwestern China. The largest changes and feedbacks between vegetation and climate occur in northern China. Northern inland ecosystems experience considerable degradation and desertification, indicating a marked sensitivity and vulnerability to climatic change. The strongest vegetation response to climate change occurs in northern China and the weakest in southern China. Vegetation feedbacks intensify warming and reduce drying due to increased CO2 during summer in northern China. Generally, vegetation-climate interactions are much stronger in northern China than in southern China.

  11. Ecological half-lives of 9Sr and 137Cs in terrestrial and aquatic ecosystems

    International Nuclear Information System (INIS)

    Proehl, G.; Ehlken, S.; Fiedler, I.; Kirchner, G.; Klemt, E.; Zibold, G.

    2006-01-01

    This paper describes the long-term behaviour of 9 Sr and 137 Cs in foods, feeds and a variety of environmental media. The long-term behaviour is quantified by means of the ecological half-life which integrates all processes that cause a decrease of activity in a given medium such as leaching, fixation and erosion. A large number of long-term time series of concentrations of radiocaesium and radiostrontium in these media have been identified and re-evaluated using a standardised statistical procedure to establish reference data sets of ecological half-lives. By example of undisturbed soils and marine water bodies it is shown that the ecological half-life concept is questionable if the distribution of the radionuclide of interest within the medium studied is non-uniform and if mixing and transport processes within this medium, therefore, are of considerable importance during the time period of observation

  12. Ecological and social dimensions of ecosystem restoration in the Nordic countries

    DEFF Research Database (Denmark)

    Hagen, Dagmar; Svavarsdottir, Kristin; Nilsson, Christer

    2013-01-01

    An international overview of the extent and type of ecological restoration can offer new perspectives for understanding, planning, and implementation. The Nordic countries, with a great range of natural conditions but historically similar social and political structures, provide an opportunity...... and among countries, both in the Nordic countries and internationally. An obvious advantage of such cooperation is that a wider range of experiences from different habitats and different socio-economic conditions becomes available and thus provides a more solid basis for developing practical solutions...... to compare restoration approaches and efforts across borders. The aim of this study was to explore variation in ecological restoration using the Nordic countries as an example. We used recent national assessments and expert evaluations of ecological restoration. Restoration efforts differed among countries...

  13. How a clogged canal impacts ecological health in a tropical urban wetland ecosystem

    Science.gov (United States)

    The coastal city of San Juan, Puerto Rico is a tropical urban ecosystem interwoven among a series of interconnected bays, lagoons, canals, and mangrove wetlands. As the city has expanded, infilling and urban encroachment on what was previously mangrove wetland and open estuarine ...

  14. How a clogged canal effects ecological and human health in a tropical urban wetland ecosystem

    Science.gov (United States)

    The coastal city of San Juan, Puerto Rico is a tropical urban ecosystem interwoven among a series of interconnected bays, lagoons, canals, and mangrove wetlands. As the city has expanded, infilling and urban encroachment on what was previously mangrove wetland and open estuarine ...

  15. Current research trends on plastic pollution and ecological impacts on the soil ecosystem: A review.

    Science.gov (United States)

    Chae, Yooeun; An, Youn-Joo

    2018-05-09

    Plastic pollution in the environment is currently receiving worldwide attention. Improper dumping of disused or abandoned plastic wastes leads to contamination of the environment. In particular, the disposal of municipal wastewater effluent, sewage sludge landfill, and plastic mulch from agricultural activities is a serious issue and of major concern regarding soil pollution. Compared to plastic pollution in the marine and freshwater ecosystems, that in the soil ecosystem has been relatively neglected. In this study, we discussed plastic pollution in the soil environment and investigated research on the effects of plastic wastes, especially microplastics, on the soil ecosystem. We found that earthworms have been predominantly used as the test species in investigating the effects of soil plastic pollution on organisms. Therefore, further research investigating the effects of plastic on other species models (invertebrates, plants, microorganisms, and insects) are required to understand the effects of plastic pollution on the overall soil ecosystem. In addition, we suggest other perspectives for future studies on plastic pollution and soil ecotoxicity of plastics wastes, providing a direction for such research. Copyright © 2018 Elsevier Ltd. All rights reserved.

  16. Soil ecology and ecosystem services of dairy and semi-natural grasslands on peat

    NARCIS (Netherlands)

    Deru, Joachim G.C.; Bloem, Jaap; Goede, de Ron; Keidel, Harm; Kloen, Henk; Rutgers, Michiel; Akker, van den Jan; Brussaard, Lijbert; Eekeren, van Nick

    2018-01-01

    Peat wetlands are of major importance for ecosystem services such as carbon storage, water regulation and maintenance of biodiversity. However, peat drainage for farming leads to CO2 emission, soil subsidence and biodiversity losses. In the peat areas in the Netherlands, solutions are sought in

  17. Major changes in the ecology of the Wadden Sea: human impacts, ecosystem engineering and sediment dynamics

    NARCIS (Netherlands)

    Eriksson, B.K.; van der Heide, T.; Van de Koppel, J.; Piersma, T.; Van der Veer, H.W.; Olff, H.

    2010-01-01

    Shallow soft-sediment systems are mostly dominated by species that, by strongly affecting sediment dynamics, modify their local environment. Such ecosystem engineering species can have either sediment-stabilizing or sediment-destabilizing effects on tidal flats. They interplay with abiotic forcing

  18. An integrated ecosystem model for coral reef management where oceanography, ecology and socio-economics meet

    NARCIS (Netherlands)

    Weijerman, M.

    2015-01-01

    Summary

    Widespread coral reef decline, including decline in reef fish populations upon which many coastal human populations depend, have led to phase-shifts from the coral-dominated systems, found desirable by humans, to algal-dominated systems that provide less ecosystem

  19. Applications of the First Law to Ecological Systems. Physical Processes in Terrestrial and Aquatic Ecosystems, Thermodynamics.

    Science.gov (United States)

    Stevenson, R. D.

    These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This report describes concepts presented in another module called "The First Law of…

  20. Linking Soil Microbial Ecology to Ecosystem Functioning in Integrated Crop-Livestock Systems

    Science.gov (United States)

    Enhanced soil stability, nutrient cycling and C sequestration potential are important ecosystem functions driven by soil microbial processes and are directly influenced by agricultural management. Integrated crop-livestock agroecosystems (ICL) can enhance these functions via high-residue returning c...

  1. A demonstration project to test ecological restoration of a pinyon-juniper ecosystem

    Science.gov (United States)

    David W. Huffman; Michael T. Stoddard; Peter Z. Fule; W. Wallace Covington; H. B. Smith

    2008-01-01

    To test an approach for restoring historical stand densities and increasing plant species diversity of a pinyon-juniper ecosystem, we implemented a demonstration project at two sites (CR and GP) on the Grand Canyon-Parashant National Monument in northern Arizona. Historical records indicated that livestock grazing was intensive on the sites beginning in the late 1800s...

  2. Habitat and Recreational Fishing Opportunity in Tampa Bay: Linking Ecological and Ecosystem Services to Human Beneficiaries

    Science.gov (United States)

    Estimating value of estuarine habitat to human beneficiaries requires that we understand how habitat alteration impacts function through both production and delivery of ecosystem goods and services (EGS). Here we expand on the habitat valuation technique of Bell (1997) with an es...

  3. An integrated ecosystem model for coral reef management where oceanography, ecology and socio-economics meet

    NARCIS (Netherlands)

    Weijerman, Mariska

    2015-01-01

    Widespread coral reef decline, including decline in reef fish populations upon which many coastal human populations depend, have led to phase-shifts from the coral-dominated systems, found desirable by humans, to algal-dominated systems that provide less ecosystem services, and the loss of

  4. ECOLOGICAL AND ENZYMATHICAL STUDY UPON SOIL RESOURCES FROM FOREST ECOSYSTEMS IN MIDDLE PRUT RIVER COURSE

    Directory of Open Access Journals (Sweden)

    Geanina Bireescu

    2006-10-01

    Full Text Available Rezultatele experimentale prezentate în lucrarea de faţă fac parte dintr-un studiu ecologic multidisciplinar desfăşurat în cadrul Programului Naţional de Cercetare BIOSTAR în ecosisteme forestiere naturale şi antropizate din Lunca Prutului (Prisecani Iaşi. Diagnoza ecologică a solului evidenţiază un potenţial trofic ridicat care nu-i utilizat la optim în sezonul estival foarte secetos. Studiul potenţialului enzimatic ne prezintă valori mijlocii, ceva mai ridicate în păduri naturale.

  5. Cross-Surface: Workshop on Interacting with Multi-Device Ecologies in the Wild

    DEFF Research Database (Denmark)

    Houben, Steven; Vermeulen, Jo; Klokmose, Clemens Nylandsted

    2015-01-01

    In this workshop, we will review and discuss opportunities, technical challenges and problems with cross-device interactions in interactive multi-surface and multi-device ecologies. We aim to bring together researchers and practitioners currently working on novel techniques for cross......-surface interactions, identify application domains and enabling technologies for cross-surface interactions in the wild, and establish a research community to develop effective strategies for successful design of cross-device interactions....

  6. The Ecology of Interactive Learning Environments: Situating Traditional Theory

    Science.gov (United States)

    Johnson, Genevieve Marie

    2014-01-01

    In educational discourse on human learning (i.e. the result of experience) and development (i.e. the result of maturation), there are three fundamental theoretical frameworks, -- behaviourism, cognitivism and constructivism, each of which have been applied, with varying degrees of success, in online environments. An ecological framework of human…

  7. Small mammal populations and ecology in the Kings River Sustainable Forest Ecosystems Project area

    Science.gov (United States)

    William F. Jr. Laudenslayer; Roberta J. Fargo

    2002-01-01

    Small mammals are important components of woodlands and forests. Since 1992, we have been studying several aspects of small mammal ecology in oak woodlands in western foothills of the southern Sierra Nevada. Assemblages of small, nocturnal mammal species are dominated by the brush mouse (Peromyscus boylii), California mouse (P. californicus...

  8. Determination of the Ecological and Geographic Distributions of Armillaria Species in Missouri Ozark Forest Ecosystems

    Science.gov (United States)

    Johann N. Bruhn; James J. Wetteroff; Jeanne D. Mihail; Susan. Burks

    1997-01-01

    Armillaria root rot contributes to oak decline in the Ozarks. Three Armillaria species were detected in Ecological Landtypes (ELT's) representing south- to west-facing side slopes (ELT 17), north- to east-facing side slopes (ELT 18), and ridge tops (ELT 11). Armillaria mellea was detected in 91 percent...

  9. Trophic ecology of Lepidoptera larvae associated with woody vegetation in a savanna ecosystem

    CSIR Research Space (South Africa)

    Scholtz, CH

    1982-06-01

    Full Text Available This study represents a quantitative survey of a Lepidoptera community and deals with the trophic ecology of the 27 species of foliage-feeding Lepidoptera on the eight dominant woody plants in the Burkea africana-Eragrostis pallens savanna...

  10. Climate change as an ecosystem architect: implications to rare plant ecology, conservation, and restoration

    Science.gov (United States)

    Constance I. Millar

    2003-01-01

    Recent advances in earth system sciences have revealed significant new information relevant to rare plant ecology and conservation. Analysis of climate change at high resolution with new and precise proxies of paleotemperatures reveals a picture over the past two million years of oscillatory climate change operating simultaneously at multiple timescales. Low-frequency...

  11. Using ecological site information to improve landscape management for ecosystem services

    Science.gov (United States)

    People and their societies, have a complicated relationship with land. The unofficial patron saint of ecologists, Aldo Leopold, in “The Sand County Almanac,” traced the modern human relationship with land from a purely economic to an ecologically based approach, culminating in his “ Land Ethic.” In...

  12. The assessment of the required groundwater quantity for the conservation of ecosystems and the achievement of a good ecological status of surface waters

    OpenAIRE

    Mitja Janža; Dejan Šram; Kim Mezga; Mišo Andjelov; Jože Uhan

    2016-01-01

    Assessment of the available quantity of groundwater is of essential importance for its sustainable use. Modern approaches for estimation of groundwater availability take into account all potential impacts of abstractions, including impacts on groundwater dependent ecosystems and impacts on surface waters ecological status. Groundwater body is in good quantitative status if groundwater abstractions do not cause signifiant damages to groundwater dependent ecosystems and signifiant d...

  13. Long-Distance Interactions Regulate the Structure and Resilience of Coastal Ecosystems

    NARCIS (Netherlands)

    van de Koppel, J.; van der Heide, T.; Altieri, A.H.; Eriksson, B.K.; Bouma, T.J.; Olff, H.; Silliman, B.R.

    2015-01-01

    Mounting evidence indicates that spatial interactions are important in structuring coastal ecosystems. Until recently, however, most of this work has been focused on seemingly exceptional systems that are characterized by regular, self-organized patterns. In this review, we document that

  14. Host-microbiota interactions within the fish intestinal ecosystem.

    Science.gov (United States)

    Pérez, T; Balcázar, J L; Ruiz-Zarzuela, I; Halaihel, N; Vendrell, D; de Blas, I; Múzquiz, J L

    2010-07-01

    Teleost fish are in direct contact with the aquatic environment, and are therefore in continual contact with a complex and dynamic microbiota, some of which may have implications for health. Mucosal surfaces represent the main sites in which environmental antigens and intestinal microbiota interact with the host. Thus, the gut-associated lymphoid tissues (GALT) must develop mechanisms to discriminate between pathogenic and commensal microorganisms. Colonization of intestinal mucosal surfaces with a normal microbiota has a positive effect on immune regulatory functions of the gut, and disturbance in these immune regulatory functions by an imbalanced microbiota may contribute to the development of diseases. Significant attention has therefore been recently focused on the role of probiotics in the induction or restoration of a disturbed microbiota to its normal beneficial composition. Given this, this article explores the fascinating relationship between the fish immune system and the bacteria that are present in its intestinal microbiota, focusing on the bacterial effect on the development of certain immune responses.

  15. Ecological Stoichiometric Characteristics of Two Typical Plantations in the Karst Ecosystem of Southwestern China

    Directory of Open Access Journals (Sweden)

    Danbo Pang

    2018-01-01

    Full Text Available Reforestation has been widely adopted to restore soil fertility and ecosystem service function in the rocky desertification region of southwestern China. However, there has been limited research concerning the stoichiometry of carbon (C, nitrogen (N, and phosphorus (P and nutrient resorption rate of plantations in karst ecosystems. In this study, we selected plantations of Pinus yunnanensis Franch. (PY and Eucalyptus maideni F. Muell. (EM in Yunnan Province. The C, N, and P concentrations and the C:N:P stoichiometry in different soil layers (0–10 cm, 10–20 cm, and 20–30 cm were examined. The nutrient limitation and nutrient resorption efficiency were also analyzed. The leaf C and N concentrations in the PY plantation were higher than that in the EM plantation; the P concentration demonstrated the opposite trend, both in green and senesced leaves. Soil C, N, and P concentrations in the EM plantation were much greater than in the PY plantation at all three depths and decreased with the depth of the soil. In addition, the high ratios of C:P, N:P, C:Available P, and N:Available P in soil coupled with the ratios of N:P in leaves indicate that the EM plantation has a greater P deficiency than the PY plantation. In the EM plantation, the relatively low P concentrations in senesced leaves indicates efficient TP (Total phosphorus resorption, which highlights that the high reuse proficiency of P could have favored moderating P limitation in the karst ecosystem. This research aids in understanding the stoichiometric characteristics that mediate forest properties, and provides a basis for management of vegetation in karst ecosystems.

  16. Newtonian boreal forest ecology: The Scots pine ecosystem as an example.

    Directory of Open Access Journals (Sweden)

    Pertti Hari

    Full Text Available Isaac Newton's approach to developing theories in his book Principia Mathematica proceeds in four steps. First, he defines various concepts, second, he formulates axioms utilising the concepts, third, he mathematically analyses the behaviour of the system defined by the concepts and axioms obtaining predictions and fourth, he tests the predictions with measurements. In this study, we formulated our theory of boreal forest ecosystems, called NewtonForest, following the four steps introduced by Newton. The forest ecosystem is a complicated entity and hence we needed altogether 27 concepts to describe the material and energy flows in the metabolism of trees, ground vegetation and microbes in the soil, and to describe the regularities in tree structure. Thirtyfour axioms described the most important features in the behaviour of the forest ecosystem. We utilised numerical simulations in the analysis of the behaviour of the system resulting in clear predictions that could be tested with field data. We collected retrospective time series of diameters and heights for test material from 6 stands in southern Finland and five stands in Estonia. The numerical simulations succeeded to predict the measured diameters and heights, providing clear corroboration with our theory.

  17. Ecological role of the giant root-rat (Tachyoryctes macrocephalus) in the Afroalpine ecosystem.

    Science.gov (United States)

    Šklíba, Jan; Vlasatá, Tereza; Lövy, Matěj; Hrouzková, Ema; Meheretu, Yonas; Sillero-Zubiri, Claudio; Šumbera, Radim

    2017-07-01

    Rodents with prevailing subterranean activity usually play an important role in the ecosystems of which they are a part due to the combined effect of herbivory and soil perturbation. This is the case for the giant root-rat Tachyoryctes macrocephalus endemic to the Afroalpine ecosystem of the Bale Mountains, Ethiopia. We studied the impact of root-rats on various ecosystem features within a 3.5-ha study locality dominated by Alchemilla pasture, which represents an optimal habitat for this species, in 2 periods of a year. The root-rats altered plant species composition, reducing the dominant forb, Alchemilla abyssinica, while enhancing Salvia merjame and a few other species, and reduced vegetation cover, but not the fresh plant biomass. Where burrows were abandoned by root-rats, other rodents took them over and A. abyssinica increased again. Root-rat burrowing created small-scale heterogeneity in soil compactness due to the backfilling of some unused burrow segments. Less compacted soil tended to be rich in nutrients, including carbon, nitrogen and phosphorus, which likely affected the plant growth on sites where the vegetation has been reduced as a result of root-rat foraging and burrowing. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  18. Evolutionary ecology of the interactions between aphids and their parasitoids.

    Science.gov (United States)

    Le Ralec, Anne; Anselme, Caroline; Outreman, Yannick; Poirié, Marylène; van Baaren, Joan; Le Lann, Cécile; van Alphen, Jacques J-M

    2010-01-01

    Many organisms, including entomopathogenous fungi, predators or parasites, use aphids as ressources. Parasites of aphids are mostly endoparasitoid insects, i.e. insects which lay eggs inside the body of an other insect which will die as a result of their development. In this article, we review the consequences of the numerous pecularities of aphid biology and ecology for their endoparasitoids, notably the Aphidiinae (Hymenoptera: Braconidae). We first examine the various mechanisms used by aphids for defence against these enemies. We then explore the strategies used by aphidiine parasitoids to exploit their aphid hosts. Finally, we consider the responses of both aphids and parasitoids to ecological constraints induced by seasonal cycles and to environmental variations linked to host plants and climate. The fundamental and applied interest of studying these organisms is discussed. Copyright 2010 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  19. The Human Threat to River Ecosystems at the Watershed Scale: An Ecological Security Assessment of the Songhua River Basin, Northeast China

    Directory of Open Access Journals (Sweden)

    Yuan Shen

    2017-03-01

    Full Text Available Human disturbances impact river basins by reducing the quality of, and services provided by, aquatic ecosystems. Conducting quantitative assessments of ecological security at the watershed scale is important for enhancing the water quality of river basins and promoting environmental management. In this study, China’s Songhua River Basin was divided into 204 assessment units by combining watershed and administrative boundaries. Ten human threat factors were identified based on their significant influence on the river ecosystem. A modified ecological threat index was used to synthetically evaluate the ecological security, where frequency was weighted by flow length from the grids to the main rivers, while severity was weighted by the potential hazard of the factors on variables of river ecosystem integrity. The results showed that individual factors related to urbanization, agricultural development and facility construction presented different spatial distribution characteristics. At the center of the plain area, the provincial capital cities posed the highest level of threat, as did the municipal districts of prefecture-level cities. The spatial relationships between hot spot locations of the ecological threat index and water quality, as well as the distribution areas of critically endangered species, were analyzed. The sensitivity analysis illustrated that alteration of agricultural development largely changed the ecological security level of the basin. By offering a reference for assessing ecological security, this study can enhance water environmental planning and management.

  20. Egocentric interaction as a tool for designing ambient ecologies – The case of the easy ADL ecology

    DEFF Research Database (Denmark)

    Surie, Dipak; Janlert, Lars-Erik; Pederson, Thomas

    2012-01-01

    ambient intelligence could be realised. This work describes such an ambient ecological system comprising of a set of smart everyday objects, a personal activity-centric middleware, a set of mock-up ubiquitous computing applications and a human agent within a living laboratory home environment......Ambient intelligence is a human-centered vision characterized by the seamless integration of information, communication, sensing and actuation, and interface technologies for supporting human agents with their everyday activities. There are many challenges to address including the need...... for an interaction paradigm that encompasses the multiple dimensions of a human agent and their environment. This work describes a human-centered interaction paradigm referred to as the egocentric interaction paradigm that considers a human agents body and mind as a centre of reference to which all interaction...

  1. Uncovering stability mechanisms in microbial ecosystems - combining microcosm experiments, computational modelling and ecological theory in a multidisciplinary approach

    Science.gov (United States)

    Worrich, Anja; König, Sara; Banitz, Thomas; Centler, Florian; Frank, Karin; Kästner, Matthias; Miltner, Anja; Thullner, Martin; Wick, Lukas

    2015-04-01

    Although bacterial degraders in soil are commonly exposed to fluctuating environmental conditions, the functional performance of the biodegradation processes can often be maintained by resistance and resilience mechanisms. However, there is still a gap in the mechanistic understanding of key factors contributing to the stability of such an ecosystem service. Therefore we developed an integrated approach combining microcosm experiments, simulation models and ecological theory to directly make use of the strengths of these disciplines. In a continuous interplay process, data, hypotheses, and central questions are exchanged between disciplines to initiate new experiments and models to ultimately identify buffer mechanisms and factors providing functional stability. We focus on drying and rewetting-cycles in soil ecosystems, which are a major abiotic driver for bacterial activity. Functional recovery of the system was found to depend on different spatial processes in the computational model. In particular, bacterial motility is a prerequisite for biodegradation if either bacteria or substrate are heterogeneously distributed. Hence, laboratory experiments focussing on bacterial dispersal processes were conducted and confirmed this finding also for functional resistance. Obtained results will be incorporated into the model in the next step. Overall, the combination of computational modelling and laboratory experiments identified spatial processes as the main driving force for functional stability in the considered system, and has proved a powerful methodological approach.

  2. Law for Country: the Structure of Warlpiri Ecological Knowledge and Its Application to Natural Resource Management and Ecosystem Stewardship

    Directory of Open Access Journals (Sweden)

    Miles C. C. Holmes

    2013-09-01

    Full Text Available Indigenous Ecological Knowledge (IEK is deeply encoded in social processes. Our research shows that from an Indigenous perspective, IEK is a way of living whose core aim is to sustain the healthy functioning of people and country through relationships of reciprocity. However, IEK is often portrayed more prosaically as a body of knowledge about the environment. We introduce a framework, called ngurra-kurlu, that enables appreciation of indigenous perspectives on IEK. The framework was identified from the collaborative work of the authors with Warlpiri aboriginal elders in the Tanami Desert region of central Australia. Ngurra-kurlu facilitates cross-cultural understanding by distilling, from a complex cultural system, the five distinct conceptual categories that comprise IEK: law, skin, ceremony, language, and country. The framework enables engagement with nuanced environmental knowledge because it synthesizes, for cross-cultural audiences, all the key areas of knowledge and practice in which IEK is located. In particular, the framework highlights how social systems mediate the transmission, deployment, and regulation of environmental knowledge in on-ground situations, including collaborative natural resource management. Although the framework was generated in relation to one indigenous group, the epistemological structure of Warlpiri IEK is relevant throughout Australia, and the framework can be applied internationally to the emerging interest in fostering ecosystem stewardship in which the cultural connections between people and place are an integral part of ecosystems management.

  3. When ecosystem services interact: crop pollination benefits depend on the level of pest control

    Science.gov (United States)

    Lundin, Ola; Smith, Henrik G.; Rundlöf, Maj; Bommarco, Riccardo

    2013-01-01

    Pollination is a key ecosystem service which most often has been studied in isolation although effects of pollination on seed set might depend on, and interact with, other services important for crop production. We tested three competing hypotheses on how insect pollination and pest control might jointly affect seed set: independent, compensatory or synergistic effects. For this, we performed a cage experiment with two levels of insect pollination and simulated pest control in red clover (Trifolium pratense L.) grown for seed. There was a synergistic interaction between the two services: the gain in seed set obtained when simultaneously increasing pollination and pest control outweighed the sum of seed set gains obtained when increasing each service separately. This study shows that interactions can alter the benefits obtained from service-providing organisms, and this needs to be considered to properly manage multiple ecosystem services. PMID:23269852

  4. Limitations of a metabolic network-based reverse ecology method for inferring host-pathogen interactions.

    Science.gov (United States)

    Takemoto, Kazuhiro; Aie, Kazuki

    2017-05-25

    Host-pathogen interactions are important in a wide range of research fields. Given the importance of metabolic crosstalk between hosts and pathogens, a metabolic network-based reverse ecology method was proposed to infer these interactions. However, the validity of this method remains unclear because of the various explanations presented and the influence of potentially confounding factors that have thus far been neglected. We re-evaluated the importance of the reverse ecology method for evaluating host-pathogen interactions while statistically controlling for confounding effects using oxygen requirement, genome, metabolic network, and phylogeny data. Our data analyses showed that host-pathogen interactions were more strongly influenced by genome size, primary network parameters (e.g., number of edges), oxygen requirement, and phylogeny than the reserve ecology-based measures. These results indicate the limitations of the reverse ecology method; however, they do not discount the importance of adopting reverse ecology approaches altogether. Rather, we highlight the need for developing more suitable methods for inferring host-pathogen interactions and conducting more careful examinations of the relationships between metabolic networks and host-pathogen interactions.

  5. Farmers’ Value Assessment of Sociocultural and Ecological Ecosystem Services in Agricultural Landscapes

    Directory of Open Access Journals (Sweden)

    Habtamu Temesgen

    2018-03-01

    Full Text Available Biophysical and economic values of ecosystem services (ESs are commonly used to define areas for land use and management planning. To date, there has been limited research conducted in Ethiopia regarding farmers’ evaluations of ESs. This article addresses farmers’ evaluations and perceptions of 16 ESs that are provided by five major land uses within two catchments, using a combined method of data generation and synthesis. Most farmers perceived the majority of land use/land cover (LUC types as multifunctional; however, they showed distinctly diverse opinions of the benefits and services that the land uses provide. The farmers also distinguished pristine ESs as different importantance depending on their location in up- or downstream regions. Accordingly, shade and shelter values in the upstream region and fodder sources in the downstream regions were among the services perceived as the most important, followed by erosion control. Conversely, water treatment and tenure security were attributed poor value. Farmers’ also identified various threats to the studied ESs that were believed to be the consequences of overpopulation coupled with climate change. Routine anthropogenic activities, woodlots extraction, agribusiness investment, and drought and rainfall variability appeared to be the main drivers of these threats. The farmers’ perceptions recorded in this study generally parallel empirical research, wherein anthropogenic and environmental challenges affect the ecosystems. This general consensus represents an important basis for the establishment of collaborative land management activities.

  6. Biological nitrogen fixation: rates, patterns and ecological controls in terrestrial ecosystems

    Science.gov (United States)

    Vitousek, Peter M.; Menge, Duncan N.L.; Reed, Sasha C.; Cleveland, Cory C.

    2013-01-01

    New techniques have identified a wide range of organisms with the capacity to carry out biological nitrogen fixation (BNF)—greatly expanding our appreciation of the diversity and ubiquity of N fixers—but our understanding of the rates and controls of BNF at ecosystem and global scales has not advanced at the same pace. Nevertheless, determining rates and controls of BNF is crucial to placing anthropogenic changes to the N cycle in context, and to understanding, predicting and managing many aspects of global environmental change. Here, we estimate terrestrial BNF for a pre-industrial world by combining information on N fluxes with 15N relative abundance data for terrestrial ecosystems. Our estimate is that pre-industrial N fixation was 58 (range of 40–100) Tg N fixed yr−1; adding conservative assumptions for geological N reduces our best estimate to 44 Tg N yr−1. This approach yields substantially lower estimates than most recent calculations; it suggests that the magnitude of human alternation of the N cycle is substantially larger than has been assumed.

  7. Ecological risk assessment of ecosystem services in the Taihu Lake Basin of China from 1985 to 2020.

    Science.gov (United States)

    Xu, Xibao; Yang, Guishan; Tan, Yan; Zhuang, Qianlai; Li, Hengpeng; Wan, Rongrong; Su, Weizhong; Zhang, Jian

    2016-06-01

    There are tremendous theoretical, methodological and policy challenges in evaluating the impact of land-use change on the degradation of ecosystem services (ES) at the regional scale. This study addresses these challenges by developing an interdisciplinary methodology based on the Procedure for Ecological Tiered Assessment of Risk (PETAR). This novel methodology integrates ecological models with a land-use change model. This study quantifies the multi-dimensional degradation risks of ES in the Taihu Lake Basin (TLB) of China from 1985 to 2020. Four key ES related to water purification, water quantity adjustment, carbon sequestration and grain production are selected. The study employs models of Denitrification-Decomposition (DNDC), Soil-Water-Atmosphere-Plant (SWAP), Biome-BGC and Agro-ecological Zoning (AEZ) for assimilations. Land-use changes by 2020 were projected using a geographically weighted multinomial logit-cellular automata (GWML-CA) model. The results show that rapid land-use change has posed a great degradation risk of ES in the region in 1985-2020. Slightly less than two-thirds of the basin experienced degradation of ES over the 1985-2010 period, and about 12% of the basin will continue to experience degradation until 2020. Hot spots with severe deterioration in 2010-2020 are projected to be centered around some small and less developed cities in the region. Regulating accelerated urban sprawl and population growth, reinforcing current environmental programs, and establishing monitoring systems for observing dynamics of regional ES are suggested as practical counter-measures. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Functional-trait ecology of the plateau pika Ochotona curzoniae (Hodgson, 1858) in the Qinghai-Tibetan Plateau ecosystem.

    Science.gov (United States)

    Smith, Andrew T; Badingqiuying; Wilson, Maxwell C; Hogan, Brigitte W

    2018-01-09

    Understanding a species' functional traits allows for a directed and productive perspective on the role a species plays in nature, thus its relative importance to conservation planning. The functional trait ecology of the plateau pika Ochotona curzoniae (Hodgson, 1858) is examined to better understand the resilience and sustainability of the high alpine grasslands of the Qinghai-Tibetan Plateau (QTP). The key functional traits of plateau pikas are their abundance and behavior of digging extensive burrow systems. Plateau pikas have been poisoned over a significant part of their original geographic distribution across the QTP, allowing comparison of ecological communities with and without pikas. Nearly all mammalian and avian carnivores, most of which are obligate predators on pikas, have been lost in regions where pikas have been poisoned. Most endemic birds on the QTP nest in pika burrows; when pikas are poisoned, burrows collapse, and these birds are greatly reduced in number. Due to the biopedturbation resulting from their burrows, regional plant species richness is higher in areas with pikas than without. The presence of pika burrows allows higher rates of infiltration during heavy monsoon rains compared to poisoned areas, possibly mitigating runoff and the potential for serious downslope erosion and flooding. Thus the functional traits of plateau pikas enhance native biodiversity and other important ecosystem functions; these traits are irreplaceable. As plateau pikas are not natural colonizers, active re-introduction programs are needed to restore pikas to areas from which they have been poisoned to restore the important functional ecological traits of pikas. This article is protected by copyright. All rights reserved.

  9. Utilization and control of ecological interactions in polymicrobial infections and community-based microbial cell factories

    DEFF Research Database (Denmark)

    Wigneswaran, Vinoth; Amador Hierro, Cristina Isabel; Jelsbak, Lotte

    2016-01-01

    Microbial activities are most often shaped by interactions between co-existing microbes within mixed-species communities. Dissection of the molecular mechanisms of species interactions within communities is a central issue in microbial ecology, and our ability to engineer and control microbial co...

  10. Mechanisms and ecological implications of plant-mediated interactions between belowground and aboveground insect herbivores

    NARCIS (Netherlands)

    Papadopoulou, G.V.; Dam, N.M. van

    2017-01-01

    Plant-mediated interactions between belowground (BG) and aboveground (AG) herbivores have received increasing interest recently. However, the molecular mechanisms underlying ecological consequences of BG–AG interactions are not fully clear yet. Herbivore-induced plant defenses are complex and

  11. Natural products mediating ecological interactions in Antarctic benthic communities: a mini-review of the known molecules.

    Science.gov (United States)

    Núñez-Pons, L; Avila, C

    2015-07-01

    Out of the many bioactive compounds described from the oceans, only a small fraction have been studied for their ecological significance. Similarly, most chemically mediated interactions are not well understood, because the molecules involved remain unrevealed. In Antarctica, this gap in knowledge is even more acute in comparison to tropical or temperate regions, even though polar organisms are also prolific producers of chemical defenses, and pharmacologically relevant products are being reported from the Southern Ocean. The extreme and unique marine environments surrounding Antarctica along with the numerous unusual interactions taking place in benthic communities are expected to select for novel functional secondary metabolites. There is an urgent need to comprehend the evolutionary role of marine derived substances in general, and particularly at the Poles, since molecules of keystone significance are vital in species survival, and therefore, in structuring the communities. Here we provide a mini-review on the identified marine natural products proven to have an ecological function in Antarctic ecosystems. This report recapitulates some of the bibliography from original Antarctic reviews, and updates the new literature in the field from 2009 to the present.

  12. [Evaluation of ecosystem service value and strategies for ecological design in land consolidation: a case of land consolidation project in Da'an City, Jilin Province, China].

    Science.gov (United States)

    Wang, Jun; Yan, Shen-Chun; Yu, Li; Zhang, Ya-Nan

    2014-04-01

    Land consolidation, as one of the major driving forces for the changes of land use/cover, has significant impacts on landscape patterns, ecological functions, and ecosystem services. In this paper, a land consolidation project conducted in Da'an City, Jinlin Province, China, was selected to evaluate the ecosystem service values before and after land consolidation at three spatial scales, i. e., village, town, and county. The results indicated that the land consolidation with the goal to increase the area of cultivated land might cause the decrease of the saline and alkaline land, grassland, and wetland. In addition, land consolidation resulted in the reduction of the total ecosystem service values at varying degree at the three scales. Compared to the pre-consolidation status, the total post-consolidation ecosystem service values at the village, town and county scales were 7.96, 843.01 and 1205.86 million yuan, and reduced by 10.5%, 14.2% and 33.1%, respectively. Based on the evaluation of ecosystem service value, strategies of landscape ecological design were discussed to improve the ecological functions and to provide the guidance for the sustainable development of land consolidation.

  13. What can we learn from the microbial ecological interactions associated with polymicrobial diseases?

    Science.gov (United States)

    Antiabong, J F; Boardman, W; Ball, A S

    2014-03-15

    Periodontal diseases in humans and animals are model polymicrobial diseases which are associated with a shift in the microbial community structure and function; there is therefore a need to investigate these diseases from a microbial ecological perspective. This review highlights three important areas of microbial ecological investigation of polymicrobial diseases and the lessons that could be learnt: (1) identification of disease-associated microbes and the implications for choice of anti-infective treatment; (2) the implications associated with vaccine design and development and (3) application of the dynamics of microbial interaction in the discovery of novel anti-infective agents. This review emphasises the need to invigorate microbial ecological approaches to the study of periodontal diseases and other polymicrobial diseases for greater understanding of the ecological interactions between and within the biotic and abiotic factors of the environment. Copyright © 2013 Elsevier B.V. All rights reserved.

  14. Diptera, fly pollination, flower visit, mutualism, ecological interaction, alternative pollinators

    Directory of Open Access Journals (Sweden)

    Barbara Gemmill-Herren

    2014-02-01

    Full Text Available While it is well recognised that pollination is an ecosystem service of vital importance to human well-being through its role in food production, it is still remarkable how little is known, on a crop-by-crop basis, about this role, and the extent and causes of declines in the service. Without better documentation of the specific contribution of pollination to crop yields, there have been mounting - and justified - questions about how relevant pollination may be to agricultural development and food security. In addition, the vast majority of studies of pollination services to crops have been carried out in Europe and North America; and certainly the problems we know to impact pollinators most severely – a high dependence on agricultural chemicals and monocropped landscapes offering little diet diversity to pollinators – are typical features of industrialised, Northern hemisphere agriculture.

  15. Dental biofilm: ecological interactions in health and disease

    NARCIS (Netherlands)

    Marsh, P.D.; Zaura, E.

    Background: The oral microbiome is diverse and exists as multispecies microbial communities on oral surfaces in structurally and functionally organized biofilms. Aim: To describe the network of microbial interactions (both synergistic and antagonistic) occurring within these biofilms and assess

  16. Cold fronts and reservoir limnology: an integrated approach towards the ecological dynamics of freshwater ecosystems.

    Science.gov (United States)

    Tundisi, J G; Matsumura-Tundisi, T; Pereira, K C; Luzia, A P; Passerini, M D; Chiba, W A C; Morais, M A; Sebastien, N Y

    2010-10-01

    In this paper the authors discuss the effects of cold fronts on the dynamics of freshwater ecosystems of southeast South America. Cold fronts originating from the Antarctic show a monthly frequency that promotes turbulence and vertical mixing in reservoirs with a consequence to homogenize nutrient distribution, dissolved oxygen and temperature. Weak thermoclines and the athelomixis process immediately before, during and after the passage of cold fronts interfere with phytoplankton succession in reservoirs. Cyanobacteria blooms in eutrophic reservoirs are frequently connected with periods of stratification and stability of the water column. Cold fronts in the Amazon and Pantanal lakes may produce fish killings during the process of "friagem" associated mixing events. Further studies will try to implement a model to predict the impact of cold fronts and prepare management procedures in order to cope with cyanobacteria blooms during warm and stable water column periods. Changes in water quality of reservoirs are expected during circulation periods caused by cold fronts.

  17. Ecology of Florida black bears in the Okefenokee-Osceola ecosystem

    Science.gov (United States)

    Dobey, S.; Masters, D.V.; Scheick, B.K.; Clark, J.D.; Pelton, M.R.; Sunquist, M.E.

    2005-01-01

    The population status of the Florida black bear (Ursus americanus floridanus) is problematic within many portions of its range and its potential listing as a federally threatened species has been the subject of legal debate. We studied Florida black bears in 2 areas in the Okefenokee-Osceola ecosystem in southeast Georgia (i.e.,Okefenokee) and north Florida (i.e., Osceola) from 1995 to 1999 to evaluate relationships between population characteristics, habitat conditions, and human activities. Bears in Okefenokee were hunted and those in Osceola were not. We captured 205 different black bears (124M:81F) 345 times from June 1995 to September  1998. We obtained 13,573 radiolocations from 87 (16M:71F) individual bears during the study.

  18. Cold fronts and reservoir limnology: an integrated approach towards the ecological dynamics of freshwater ecosystems

    Directory of Open Access Journals (Sweden)

    JG. Tundisi

    Full Text Available In this paper the authors discuss the effects of cold fronts on the dynamics of freshwater ecosystems of southeast South America. Cold fronts originating from the Antarctic show a monthly frequency that promotes turbulence and vertical mixing in reservoirs with a consequence to homogenize nutrient distribution, dissolved oxygen and temperature. Weak thermoclines and the athelomixis process immediately before, during and after the passage of cold fronts interfere with phytoplankton succession in reservoirs. Cyanobacteria blooms in eutrophic reservoirs are frequently connected with periods of stratification and stability of the water column. Cold fronts in the Amazon and Pantanal lakes may produce fish killings during the process of "friagem" associated mixing events. Further studies will try to implement a model to predict the impact of cold fronts and prepare management procedures in order to cope with cyanobacteria blooms during warm and stable water column periods. Changes in water quality of reservoirs are expected during circulation periods caused by cold fronts.

  19. Exposure to violence across the social ecosystem and the development of aggression: a test of ecological theory in the Israeli-Palestinian conflict.

    Science.gov (United States)

    Boxer, Paul; Rowell Huesmann, L; Dubow, Eric F; Landau, Simha F; Gvirsman, Shira Dvir; Shikaki, Khalil; Ginges, Jeremy

    2013-01-01

    Bronfenbrenner's (1979) ecological model proposes that events in higher order social ecosystems should influence human development through their impact on events in lower order social ecosystems. This proposition was tested with respect to ecological violence and the development of children's aggression via analyses of 3 waves of data (1 wave yearly for 3 years) from 3 age cohorts (starting ages: 8, 11, and 14) representing three populations in the Middle East: Palestinians (N = 600), Israeli Jews (N = 451), and Israeli Arabs (N = 450). Results supported a hypothesized model in which ethnopolitical violence increases community, family, and school violence and children's aggression. Findings are discussed with respect to ecological and observational learning perspectives on the development of aggressive behavior. © 2012 The Authors. Child Development © 2012 Society for Research in Child Development, Inc.

  20. Metrics to assess ecological condition, change, and impacts in sandy beach ecosystems.

    Science.gov (United States)

    Schlacher, Thomas A; Schoeman, David S; Jones, Alan R; Dugan, Jenifer E; Hubbard, David M; Defeo, Omar; Peterson, Charles H; Weston, Michael A; Maslo, Brooke; Olds, Andrew D; Scapini, Felicita; Nel, Ronel; Harris, Linda R; Lucrezi, Serena; Lastra, Mariano; Huijbers, Chantal M; Connolly, Rod M

    2014-11-01

    Complexity is increasingly the hallmark in environmental management practices of sandy shorelines. This arises primarily from meeting growing public demands (e.g., real estate, recreation) whilst reconciling economic demands with expectations of coastal users who have modern conservation ethics. Ideally, shoreline management is underpinned by empirical data, but selecting ecologically-meaningful metrics to accurately measure the condition of systems, and the ecological effects of human activities, is a complex task. Here we construct a framework for metric selection, considering six categories of issues that authorities commonly address: erosion; habitat loss; recreation; fishing; pollution (litter and chemical contaminants); and wildlife conservation. Possible metrics were scored in terms of their ability to reflect environmental change, and against criteria that are widely used for judging the performance of ecological indicators (i.e., sensitivity, practicability, costs, and public appeal). From this analysis, four types of broadly applicable metrics that also performed very well against the indicator criteria emerged: 1.) traits of bird populations and assemblages (e.g., abundance, diversity, distributions, habitat use); 2.) breeding/reproductive performance sensu lato (especially relevant for birds and turtles nesting on beaches and in dunes, but equally applicable to invertebrates and plants); 3.) population parameters and distributions of vertebrates associated primarily with dunes and the supralittoral beach zone (traditionally focused on birds and turtles, but expandable to mammals); 4.) compound measurements of the abundance/cover/biomass of biota (plants, invertebrates, vertebrates) at both the population and assemblage level. Local constraints (i.e., the absence of birds in highly degraded urban settings or lack of dunes on bluff-backed beaches) and particular issues may require alternatives. Metrics - if selected and applied correctly - provide

  1. Key features for more successful place-based sustainability research on social-ecological systems: a Programme on Ecosystem Change and Society (PECS perspective

    Directory of Open Access Journals (Sweden)

    Patricia Balvanera

    2017-03-01

    Full Text Available The emerging discipline of sustainability science is focused explicitly on the dynamic interactions between nature and society and is committed to research that spans multiple scales and can support transitions toward greater sustainability. Because a growing body of place-based social-ecological sustainability research (PBSESR has emerged in recent decades, there is a growing need to understand better how to maximize the effectiveness of this work. The Programme on Ecosystem Change and Society (PECS provides a unique opportunity for synthesizing insights gained from this research community on key features that may contribute to the relative success of PBSESR. We surveyed the leaders of PECS-affiliated projects using a combination of open, closed, and semistructured questions to identify which features of a research project are perceived to contribute to successful research design and implementation. We assessed six types of research features: problem orientation, research team, and contextual, conceptual, methodological, and evaluative features. We examined the desirable and undesirable aspects of each feature, the enabling factors and obstacles associated with project implementation, and asked respondents to assess the performance of their own projects in relation to these features. Responses were obtained from 25 projects working in 42 social-ecological study cases within 25 countries. Factors that contribute to the overall success of PBSESR included: explicitly addressing integrated social-ecological systems; a focus on solution- and transformation-oriented research; adaptation of studies to their local context; trusted, long-term, and frequent engagement with stakeholders and partners; and an early definition of the purpose and scope of research. Factors that hindered the success of PBSESR included: the complexities inherent to social-ecological systems, the imposition of particular epistemologies and methods on the wider research group

  2. Naïveté in novel ecological interactions: lessons from theory and experimental evidence.

    Science.gov (United States)

    Carthey, Alexandra J R; Banks, Peter B

    2014-11-01

    The invasion of alien species into areas beyond their native ranges is having profound effects on ecosystems around the world. In particular, novel alien predators are causing rapid extinctions or declines in many native prey species, and these impacts are generally attributed to ecological naïveté or the failure to recognise a novel enemy and respond appropriately due to a lack of experience. Despite a large body of research concerning the recognition of alien predation risk by native prey, the literature lacks an extensive review of naïveté theory that specifically asks how naïveté between novel pairings of alien predators and native prey disrupts our classical understanding of predator-prey ecological theory. Here we critically review both classic and current theory relating to predator-prey interactions between both predators and prey with shared evolutionary histories, and those that are ecologically 'mismatched' through the outcomes of biological invasions. The review is structured around the multiple levels of naïveté framework of Banks & Dickman (2007), and concepts and examples are discussed as they relate to each stage in the process from failure to recognise a novel predator (Level 1 naïveté), through to appropriate (Level 2) and effective (Level 3) antipredator responses. We discuss the relative contributions of recognition, cue types and the implied risk of cues used by novel alien and familiar native predators, to the probability that prey will recognise a novel predator. We then cover the antipredator response types available to prey and the factors that predict whether these responses will be appropriate or effective against novel alien and familiar native predators. In general, the level of naïveté of native prey can be predicted by the degree of novelty (in terms of appearance, behaviour or habitat use) of the alien predator compared to native predators with which prey are experienced. Appearance in this sense includes cue types

  3. Ecological Interactions of Bacteria in the Human Gut

    Science.gov (United States)

    Falony, Gwen; de Vuyst, Luc

    The colon or large intestine is one of the most important organs of the human body (Macfarlane and Cummings, 1991). Moreover, its inhabitants, the colon microbiota, are the key elements of the human digestive ecosystem. The vast complexity of the human large-intestinal microbiota has inspired researchers to consider it as an organ itself, located inside the colon and acquired postnatally (Bäckhed et al., 2005; Zocco et al., 2007). From a physiologist's point of view, this image of the colon microbiota is relevant: like an organ, it is composed of different cell lineages that communicate with both one another and the host; it consumes, stores, and redistributes energy; it mediates physiologically important chemical transformations; and it is able to maintain and repair itself through self-replication (Bäckhed et al., 2005). As a microbial organ, the human colon community does not only broaden the digestive abilities of the host (Gill et al., 2006), but also influences body processes far beyond digestion (Roberfroid, 2005b; Turnbaugh et al., 2007).

  4. IRBAS: An online database to collate, analyze, and synthesize data on the biodiversity and ecology of intermittent rivers worldwide

    Science.gov (United States)

    Key questions dominating contemporary ecological research and management concern interactions between biodiversity, ecosystem processes, and ecosystem services provision in the face of global change. This is particularly salient for freshwater biodiversity and in the context of r...

  5. Implications of agricultural transitions and urbanization for ecosystem services.

    Science.gov (United States)

    Cumming, Graeme S; Buerkert, Andreas; Hoffmann, Ellen M; Schlecht, Eva; von Cramon-Taubadel, Stephan; Tscharntke, Teja

    2014-11-06

    Historically, farmers and hunter-gatherers relied directly on ecosystem services, which they both exploited and enjoyed. Urban populations still rely on ecosystems, but prioritize non-ecosystem services (socioeconomic). Population growth and densification increase the scale and change the nature of both ecosystem- and non-ecosystem-service supply and demand, weakening direct feedbacks between ecosystems and societies and potentially pushing social-ecological systems into traps that can lead to collapse. The interacting and mutually reinforcing processes of technological change, population growth and urbanization contribute to over-exploitation of ecosystems through complex feedbacks that have important implications for sustainable resource use.

  6. Interactions between soil thermal and hydrological dynamics in the response of Alaska ecosystems to fire disturbance

    Science.gov (United States)

    Yi, Shuhua; McGuire, A. David; Harden, Jennifer; Kasischke, Eric; Manies, Kristen L.; Hinzman, Larry; Liljedahl, Anna K.; Randerson, J.; Liu, Heping; Romanovsky, Vladimir E.; Marchenko, Sergey S.; Kim, Yongwon

    2009-01-01

    Soil temperature and moisture are important factors that control many ecosystem processes. However, interactions between soil thermal and hydrological processes are not adequately understood in cold regions, where the frozen soil, fire disturbance, and soil drainage play important roles in controlling interactions among these processes. These interactions were investigated with a new ecosystem model framework, the dynamic organic soil version of the Terrestrial Ecosystem Model, that incorporates an efficient and stable numerical scheme for simulating soil thermal and hydrological dynamics within soil profiles that contain a live moss horizon, fibrous and amorphous organic horizons, and mineral soil horizons. The performance of the model was evaluated for a tundra burn site that had both preburn and postburn measurements, two black spruce fire chronosequences (representing space-for-time substitutions in well and intermediately drained conditions), and a poorly drained black spruce site. Although space-for-time substitutions present challenges in model-data comparison, the model demonstrates substantial ability in simulating the dynamics of evapotranspiration, soil temperature, active layer depth, soil moisture, and water table depth in response to both climate variability and fire disturbance. Several differences between model simulations and field measurements identified key challenges for evaluating/improving model performance that include (1) proper representation of discrepancies between air temperature and ground surface temperature; (2) minimization of precipitation biases in the driving data sets; (3) improvement of the measurement accuracy of soil moisture in surface organic horizons; and (4) proper specification of organic horizon depth/properties, and soil thermal conductivity.

  7. Soil ecological interactions: comparisons between tropical and subalpine forests

    Science.gov (United States)

    Grizelle Gonzalez; Ruth E. Ley; Steven K. Schmidt; Xiaoming Zou; Timothy R. Seastedt

    2001-01-01

    Soil fauna can influence soil processes through interactions with the microbial community. Due to the complexity of the functional roles of fauna and their effects on microbes, little consensus has been reached on the extent to which soil fauna can regulate microbial activities. We quantified soil microbial biomass and maximum growth rates in control and fauna-excluded...

  8. Interactive effects of air pollution and climate change on forest ecosystems in the United States: current understanding and future scenarios

    Science.gov (United States)

    Andrzej Bytnerowicz; Mark Fenn; Steven McNulty; Fengming Yuan; Afshin Pourmokhtarian; Charles Driscoll; Tom Meixner

    2013-01-01

    A review of the current status of air pollution and climate change (CC) in the United States from a perspective of their impacts on forest ecosystems is provided. Ambient ozone (O3) and nitrogen (N) deposition have important and widespread ecological impacts in U.S. forests. Effects of sulphurous (S) air pollutants and other trace pollutants have...

  9. The terrestrial isopod microbiome: An all-in-one toolbox for animal-microbe interactions of ecological relevance

    Directory of Open Access Journals (Sweden)

    Didier Bouchon

    2016-09-01

    Full Text Available Bacterial symbionts represent essential drivers of arthropod ecology and evolution, influencing host traits such as nutrition, reproduction, immunity and speciation. However, the majority of work on arthropod microbiota has been conducted in insects and more studies in non-model species across different ecological niches will be needed to complete our understanding of host-microbiota interactions. In this review, we present terrestrial isopod crustaceans as an emerging model organism to investigate symbiotic associations with potential relevance to ecosystem functioning. Terrestrial isopods comprise a group of crustaceans that have evolved a terrestrial lifestyle and represent keystone species in terrestrial ecosystems, contributing to the decomposition of organic matter and regulating the microbial food web. Since their nutrition is based on plant detritus, it has long been suspected that bacterial symbionts located in the digestive tissues might play an important role in host nutrition via the provisioning of digestive enzymes, thereby enabling the utilization of recalcitrant food compounds (e.g. cellulose or lignins. If this were the case, then (i the acquisition of these bacteria might have been an important evolutionary prerequisite for the colonization of land by isopods, and (ii these bacterial symbionts would directly mediate the role of their hosts in ecosystem functioning. Several bacterial symbionts have indeed been discovered in the midgut caeca of terrestrial isopods and some of them might be specific to this group of animals (i.e. Candidatus Hepatoplasma crinochetorum, Candidatus Hepatincola porcellionum and Rhabdochlamydia porcellionis, while others are well-known intracellular pathogens (Rickettsiella spp. or reproductive parasites (Wolbachia sp.. Moreover, a recent investigation of the microbiota in Armadillidium vulgare has revealed that this species harbors a highly diverse bacterial community which varies between host

  10. The Terrestrial Isopod Microbiome: An All-in-One Toolbox for Animal-Microbe Interactions of Ecological Relevance.

    Science.gov (United States)

    Bouchon, Didier; Zimmer, Martin; Dittmer, Jessica

    2016-01-01

    Bacterial symbionts represent essential drivers of arthropod ecology and evolution, influencing host traits such as nutrition, reproduction, immunity, and speciation. However, the majority of work on arthropod microbiota has been conducted in insects and more studies in non-model species across different ecological niches will be needed to complete our understanding of host-microbiota interactions. In this review, we present terrestrial isopod crustaceans as an emerging model organism to investigate symbiotic associations with potential relevance to ecosystem functioning. Terrestrial isopods comprise a group of crustaceans that have evolved a terrestrial lifestyle and represent keystone species in terrestrial ecosystems, contributing to the decomposition of organic matter and regulating the microbial food web. Since their nutrition is based on plant detritus, it has long been suspected that bacterial symbionts located in the digestive tissues might play an important role in host nutrition via the provisioning of digestive enzymes, thereby enabling the utilization of recalcitrant food compounds (e.g., cellulose or lignins). If this were the case, then (i) the acquisition of these bacteria might have been an important evolutionary prerequisite for the colonization of land by isopods, and (ii) these bacterial symbionts would directly mediate the role of their hosts in ecosystem functioning. Several bacterial symbionts have indeed been discovered in the midgut caeca of terrestrial isopods and some of them might be specific to this group of animals (i.e., Candidatus Hepatoplasma crinochetorum, Candidatus Hepatincola porcellionum, and Rhabdochlamydia porcellionis ), while others are well-known intracellular pathogens ( Rickettsiella spp.) or reproductive parasites ( Wolbachia sp.). Moreover, a recent investigation of the microbiota in Armadillidium vulgare has revealed that this species harbors a highly diverse bacterial community which varies between host populations

  11. Ecological and Biogeochemical Impacts of Internal Waves on Mesophotic Coral Ecosystems: Testing Eddy Covariance and Isotope Approaches, Iriomote, Japan

    Science.gov (United States)

    Wyatt, A. S. J.; Miyajima, T.; Leichter, J.; Naruse, T.; Kuwae, T.; Yamamoto, S.; Satoh, N.; Nagata, T.

    2016-02-01

    Mesophotic coral ecosystems (MCE) occur in the `twilight zone' of decreasing light between 30 - 150 m water depth where they may be protected or damped from disturbances impacting shallower reefs. However insufficient information is available on the environmental conditions that support MCE to allow us to understand and conserve these `deep water refugia'. For instance, nutrient inputs and recycling have rarely been quantified over MCE, but deeper reefs may differ fundamentally to that of shallow counterparts due to the reduction in light and increasing use of oceanic nutrients at the base of the food web, leading to increased reliance on heterotrophy over autotrophy at species and ecosystem levels and stronger links to oceanic processes. For instance, due to their depth relative to typical water column density stratification, MCE are particularly likely to experience internal wave forcing, the significance of which should vary spatially depending on aspect and exposure. In this study we are focusing on MCE occurring along a continuum of oceanic-exposure along Funauki Bay on the west coast of Iriomote, Japan. Here our preliminary observations indicate that ocean-exposed MCE are subject to semi-diurnal temperature oscillations of up to 4 C during summer (range 23 - 29 deg C), while inner bay MCE occur at shallower depths in more turbid but stable environments. This continuum of oceanic exposure is ideal for testing a range of approaches for quantifying the relative ecological and biogeochemical influence of internal waves. Stable isotope analyses (SIA) are a particularly useful tool for understanding functional links between oceanic processes, local-scale nutrient cycling, and trophic ecology, with results from shallow reefs showing they likely function along a continuum of reliance on external inputs versus internal recycling depending on the degree of oceanic exposure. Although challenging to implement in deep water habitats, the combination of SIA with compound

  12. Drought effects on ecosystem functioning and interactions with CO2 and warming - results from CLIMAITE

    Science.gov (United States)

    Beier, Claus; Ibrom, Andreas; Linden, Leon G.; Selsted, Merete B.; Albert, Kristian R.; Kongstad, Jane; Andresen, Louise C.

    2010-05-01

    both processes responsible for inputs and outputs of carbon with an overall effect of drought reducing the carbon gain in the ecosystem. Long term changes in rewetting capability observed in other drought studies (Sowerby et al., 2009) are not visible in the CLIMAITE experiment yet. Elevated CO2 improves the water use efficiency and thereby reduces the water use and water stress in the ecosystem during droughts. Consequently, a higher plant growth and carbon gain can be maintained during dry periods. Higher water status during dry periods might also stimulate carbon turnover by microbes, but this effect is, at least on the short term less prominent than the effect on plant growth and CO2 in combination with drought seemed to stimulate ecosystem carbon gain. Increased temperature may amplify reduced water availability by stimulating evapotranspiration, and the responses in CLIMAITE generally support this with reduced plant growth and carbon uptake in plants when temperature and drought was combined. Furthermore, it might be expected that elevated temperature stimulates soil carbon mineralisation leading to an overall reduction in ecosystem carbon gain when the ecosystem is exposed to both warming and drought. However, the short term results from CLIMAITE are inconclusive on this point with generally small and varied responses to warming. The full factorial experiment shows clear interactions among factors and simple precipitation change experiments may not provide a valid picture of the responses to the combined climate change scenario, even at the short term. On the longer term more complex interactions may occur and make prediction even more uncertain. In relation to water this may in particular be linked to long term changes in soil structure and microbial biomass as well as changes in plant species composition leading to dominating plants with better opportunities to deal with either limited or fluctuating water availability. The CLIMAITE studies support emerging

  13. Reconstructing past ecological networks: the reconfiguration of seed-dispersal interactions after megafaunal extinction.

    Science.gov (United States)

    Pires, Mathias M; Galetti, Mauro; Donatti, Camila I; Pizo, Marco A; Dirzo, Rodolfo; Guimarães, Paulo R

    2014-08-01

    The late Quaternary megafaunal extinction impacted ecological communities worldwide, and affected key ecological processes such as seed dispersal. The traits of several species of large-seeded plants are thought to have evolved in response to interactions with extinct megafauna, but how these extinctions affected the organization of interactions in seed-dispersal systems is poorly understood. Here, we combined ecological and paleontological data and network analyses to investigate how the structure of a species-rich seed-dispersal network could have changed from the Pleistocene to the present and examine the possible consequences of such changes. Our results indicate that the seed-dispersal network was organized into modules across the different time periods but has been reconfigured in different ways over time. The episode of megafaunal extinction and the arrival of humans changed how seed dispersers were distributed among network modules. However, the recent introduction of livestock into the seed-dispersal system partially restored the original network organization by strengthening the modular configuration. Moreover, after megafaunal extinctions, introduced species and some smaller native mammals became key components for the structure of the seed-dispersal network. We hypothesize that such changes in network structure affected both animal and plant assemblages, potentially contributing to the shaping of modern ecological communities. The ongoing extinction of key large vertebrates will lead to a variety of context-dependent rearranged ecological networks, most certainly affecting ecological and evolutionary processes.

  14. A spatially explicit hydro-ecological modeling framework (BEPS-TerrainLab V2.0): Model description and test in a boreal ecosystem in Eastern North America

    Science.gov (United States)

    Govind, Ajit; Chen, Jing Ming; Margolis, Hank; Ju, Weimin; Sonnentag, Oliver; Giasson, Marc-André

    2009-04-01

    SummaryA spatially explicit, process-based hydro-ecological model, BEPS-TerrainLab V2.0, was developed to improve the representation of ecophysiological, hydro-ecological and biogeochemical processes of boreal ecosystems in a tightly coupled manner. Several processes unique to boreal ecosystems were implemented including the sub-surface lateral water fluxes, stratification of vegetation into distinct layers for explicit ecophysiological representation, inclusion of novel spatial upscaling strategies and biogeochemical processes. To account for preferential water fluxes common in humid boreal ecosystems, a novel scheme was introduced based on laboratory analyses. Leaf-scale ecophysiological processes were upscaled to canopy-scale by explicitly considering leaf physiological conditions as affected by light and water stress. The modified model was tested with 2 years of continuous measurements taken at the Eastern Old Black Spruce Site of the Fluxnet-Canada Research Network located in a humid boreal watershed in eastern Canada. Comparison of the simulated and measured ET, water-table depth (WTD), volumetric soil water content (VSWC) and gross primary productivity (GPP) revealed that BEPS-TerrainLab V2.0 simulates hydro-ecological processes with reasonable accuracy. The model was able to explain 83% of the ET, 92% of the GPP variability and 72% of the WTD dynamics. The model suggests that in humid ecosystems such as eastern North American boreal watersheds, topographically driven sub-surface baseflow is the main mechanism of soil water partitioning which significantly affects the local-scale hydrological conditions.

  15. Ecosystem Interactions Underlie the Spread of Avian Influenza A Viruses with Pandemic Potential.

    Directory of Open Access Journals (Sweden)

    Justin Bahl

    2016-05-01

    Full Text Available Despite evidence for avian influenza A virus (AIV transmission between wild and domestic ecosystems, the roles of bird migration and poultry trade in the spread of viruses remain enigmatic. In this study, we integrate ecosystem interactions into a phylogeographic model to assess the contribution of wild and domestic hosts to AIV distribution and persistence. Analysis of globally sampled AIV datasets shows frequent two-way transmission between wild and domestic ecosystems. In general, viral flow from domestic to wild bird populations was restricted to within a geographic region. In contrast, spillover from wild to domestic populations occurred both within and between regions. Wild birds mediated long-distance dispersal at intercontinental scales whereas viral spread among poultry populations was a major driver of regional spread. Viral spread between poultry flocks frequently originated from persistent lineages circulating in regions of intensive poultry production. Our analysis of long-term surveillance data demonstrates that meaningful insights can be inferred from integrating ecosystem into phylogeographic reconstructions that may be consequential for pandemic preparedness and livestock protection.

  16. Ecosystem Interactions Underlie the Spread of Avian Influenza A Viruses with Pandemic Potential

    Science.gov (United States)

    Bahl, Justin; Pham, Truc T.; Hill, Nichola J.; Hussein, Islam T. M.; Ma, Eric J.; Easterday, Bernard C.; Halpin, Rebecca A.; Stockwell, Timothy B.; Wentworth, David E.; Kayali, Ghazi; Krauss, Scott; Schultz-Cherry, Stacey; Webster, Robert G.; Webby, Richard J.; Swartz, Michael D.; Smith, Gavin J. D.; Runstadler, Jonathan A.

    2016-01-01

    Despite evidence for avian influenza A virus (AIV) transmission between wild and domestic ecosystems, the roles of bird migration and poultry trade in the spread of viruses remain enigmatic. In this study, we integrate ecosystem interactions into a phylogeographic model to assess the contribution of wild and domestic hosts to AIV distribution and persistence. Analysis of globally sampled AIV datasets shows frequent two-way transmission between wild and domestic ecosystems. In general, viral flow from domestic to wild bird populations was restricted to within a geographic region. In contrast, spillover from wild to domestic populations occurred both within and between regions. Wild birds mediated long-distance dispersal at intercontinental scales whereas viral spread among poultry populations was a major driver of regional spread. Viral spread between poultry flocks frequently originated from persistent lineages circulating in regions of intensive poultry production. Our analysis of long-term surveillance data demonstrates that meaningful insights can be inferred from integrating ecosystem into phylogeographic reconstructions that may be consequential for pandemic preparedness and livestock protection. PMID:27166585

  17. Ecological turmoil in evolutionary dynamics of plant-insect interactions: defense to offence

    Czech Academy of Sciences Publication Activity Database

    Mishra, Manasi; Lomate, P. R.; Joshi, R. S.; Punekar, S. A.; Gupta, V. S.; Giri, A. P.

    2015-01-01

    Roč. 242, č. 4 (2015), s. 761-771 ISSN 0032-0935 Institutional support: RVO:61388963 Keywords : plant-insect interaction * co-evolution * human interference * ecosystem * climatic change Subject RIV: CE - Biochemistry Impact factor: 3.239, year: 2015

  18. Evolution in a Community Context: On Integrating Ecological Interactions and Macroevolution.

    Science.gov (United States)

    Weber, Marjorie G; Wagner, Catherine E; Best, Rebecca J; Harmon, Luke J; Matthews, Blake

    2017-04-01

    Despite a conceptual understanding that evolution and species interactions are inextricably linked, it remains challenging to study ecological and evolutionary dynamics together over long temporal scales. In this review, we argue that, despite inherent challenges associated with reconstructing historical processes, the interplay of ecology and evolution is central to our understanding of macroevolution and community coexistence, and cannot be safely ignored in community and comparative phylogenetic studies. We highlight new research avenues that foster greater consideration of both ecological and evolutionary dynamics as processes that occur along branches of phylogenetic trees. By promoting new ways forward using this perspective, we hope to inspire further integration that creatively co-utilizes phylogenies and ecological data to study eco-evolutionary dynamics over time and space. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. A Socio-Ecological Approach for Identifying and Contextualising Spatial Ecosystem-Based Adaptation Priorities at the Sub-National Level

    Science.gov (United States)

    Bourne, Amanda; Holness, Stephen; Holden, Petra; Scorgie, Sarshen; Donatti, Camila I.; Midgley, Guy

    2016-01-01

    Climate change adds an additional layer of complexity to existing sustainable development and biodiversity conservation challenges. The impacts of global climate change are felt locally, and thus local governance structures will increasingly be responsible for preparedness and local responses. Ecosystem-based adaptation (EbA) options are gaining prominence as relevant climate change solutions. Local government officials seldom have an appropriate understanding of the role of ecosystem functioning in sustainable development goals, or access to relevant climate information. Thus the use of ecosystems in helping people adapt to climate change is limited partially by the lack of information on where ecosystems have the highest potential to do so. To begin overcoming this barrier, Conservation South Africa in partnership with local government developed a socio-ecological approach for identifying spatial EbA priorities at the sub-national level. Using GIS-based multi-criteria analysis and vegetation distribution models, the authors have spatially integrated relevant ecological and social information at a scale appropriate to inform local level political, administrative, and operational decision makers. This is the first systematic approach of which we are aware that highlights spatial priority areas for EbA implementation. Nodes of socio-ecological vulnerability are identified, and the inclusion of areas that provide ecosystem services and ecological resilience to future climate change is innovative. The purpose of this paper is to present and demonstrate a methodology for combining complex information into user-friendly spatial products for local level decision making on EbA. The authors focus on illustrating the kinds of products that can be generated from combining information in the suggested ways, and do not discuss the nuance of climate models nor present specific technical details of the model outputs here. Two representative case studies from rural South Africa

  20. A Socio-Ecological Approach for Identifying and Contextualising Spatial Ecosystem-Based Adaptation Priorities at the Sub-National Level.

    Directory of Open Access Journals (Sweden)

    Amanda Bourne

    Full Text Available Climate change adds an additional layer of complexity to existing sustainable development and biodiversity conservation challenges. The impacts of global climate change are felt locally, and thus local governance structures will increasingly be responsible for preparedness and local responses. Ecosystem-based adaptation (EbA options are gaining prominence as relevant climate change solutions. Local government officials seldom have an appropriate understanding of the role of ecosystem functioning in sustainable development goals, or access to relevant climate information. Thus the use of ecosystems in helping people adapt to climate change is limited partially by the lack of information on where ecosystems have the highest potential to do so. To begin overcoming this barrier, Conservation South Africa in partnership with local government developed a socio-ecological approach for identifying spatial EbA priorities at the sub-national level. Using GIS-based multi-criteria analysis and vegetation distribution models, the authors have spatially integrated relevant ecological and social information at a scale appropriate to inform local level political, administrative, and operational decision makers. This is the first systematic approach of which we are aware that highlights spatial priority areas for EbA implementation. Nodes of socio-ecological vulnerability are identified, and the inclusion of areas that provide ecosystem services and ecological resilience to future climate change is innovative. The purpose of this paper is to present and demonstrate a methodology for combining complex information into user-friendly spatial products for local level decision making on EbA. The authors focus on illustrating the kinds of products that can be generated from combining information in the suggested ways, and do not discuss the nuance of climate models nor present specific technical details of the model outputs here. Two representative case studies from

  1. Spatial effects of aboveground biomass on soil ecological parameters and trace gas fluxes in a savannah ecosystem of Mount Kilimanjaro

    Science.gov (United States)

    Becker, Joscha; Gütlein, Adrian; Sierra Cornejo, Natalia; Kiese, Ralf; Hertel, Dietrich; Kuzyakov, Yakov

    2015-04-01

    The savannah biome is a hotspot for biodiversity and wildlife conservation in Africa and recently got in the focus of research on carbon sequestration. Savannah ecosystems are under strong pressure from climate and land-use change, especially around populous areas like the Mt. Kilimanjaro region. Savannah vegetation in this area consists of grassland with isolated trees and is therefore characterized by high spatial variation of canopy cover, aboveground biomass and root structure. Canopy structure is known to affect microclimate, throughfall and evapotranspiration and thereby controls soil moisture conditions. Consequently, the canopy structure is a major regulator for soil ecological parameters and soil-atmospheric trace gas exchange (CO2, N2O, CH4) in water limited environments. The spatial distribution of these parameters and the connection between above and belowground processes are important to understand and predict ecosystem changes and estimate its vulnerability. Our objective was to determine trends and changes of soil parameters and relate their spatial variability to the vegetation structure. We chose three trees from each of the two most dominant species (Acacia nilotica and Balanites aegyptiaca) in our research area. For each tree, we selected transects with nine sampling points of the same relative distances to the stem. Distances were calculated in relation to the crown radius. At these each sampling point a soil core was taken and separated in 0-10 cm and 10-30 cm depth. We measured soil carbon (C) and nitrogen (N) storage, microbial biomass carbon C and N, soil respiration as well as root biomass and -density, soil temperature and soil water content. Each tree was characterized by crown spread, leaf area index and basal area. Preliminary results show that C and N stocks decreased about 50% with depth independently of distance to the tree. Soil water content under the tree crown increased with depth while it decreased under grass cover. Microbial

  2. Applying principles from economics to improve the transfer of ecological production estimates in fisheries ecosystem services research

    Science.gov (United States)

    Ecosystem services (ES) represent a way to represent and quantify multiple uses, values as well as connectivity between ecosystem processes and human well-being. Ecosystem-based fisheries management approaches may seek to quantify expected trade-offs in ecosystem services due to ...

  3. The Ecology of Shallow Lakes - Trophic Interactions in the Pelagial

    DEFF Research Database (Denmark)

    Jeppesen, E.

    publications. The thesis was in June 1998 approved by The Faculty of Natural Sciences at the University of Copenhagen for defence for the doctor´s degree in Natural Sciences (D.sc). This thesis describes how biological interactions in the pelagial of lakes change across both nutrients and depth gradients......The defence took place on December 11, 1998 at The Freshwater Centre, Silkeborg, Denmark. Officiel opponents was Prof. Jürgen Benndorf, University of Technology, Dresden,Germany and Prof. Dag Hessen, University of Oslo, Norway . The defence was led by Lektor Leif Lau Jeppesen, Zoological Institute...

  4. Analysis of trophic interactions reveals highly plastic response to climate change in a tri-trophic High-Arctic ecosystem

    DEFF Research Database (Denmark)

    Mortensen, Lars O.; Schmidt, Niels Martin; Hoye, Toke T.

    2016-01-01

    As a response to current climate changes, individual species have changed various biological traits, illustrating an inherent phenotypic plasticity. However, as species are embedded in an ecological network characterised by multiple consumer-resource interactions, ecological mismatches are likely...... to arise when interacting species do not respond homogeneously. The approach of biological networks analysis calls for the use of structural equation modelling (SEM), a multidimensional analytical setup that has proven particularly useful for analysing multiple interactions across trophic levels. Here we...

  5. Volcano ecology: Disturbance characteristics and assembly of biological communities

    Science.gov (United States)

    Volcanic eruptions are powerful expressions of Earth’s geophysical forces which have shaped and influenced ecological systems since the earliest days of life. The study of the interactions of volcanoes and ecosystems, termed volcano ecology, focuses on the ecological responses of organisms and biolo...

  6. Landscape ecology: what is the state of science?

    Science.gov (United States)

    Monica G. Turner

    2005-01-01

    Landscape ecology focuses on the reciprocal interactions between spatial pattern and ecological processes, and it is well integrated with ecology. The field has grown rapidly over the past 15 years. The persistent influence of land-use history and natural disturbance on contemporary ecosystems has become apparent Development of pattern metrics has largely stabilized,...

  7. Ecological effects assessment of anionic surfactant on aquatic ecosystem using microcosm system; Microcosm wo mochiita in ion kaimen kasseizai no suiken seitaikei ni oyobosu eikyo hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Takamatsu, Y. [University of Tsukuba, Tsukuba (Japan); Inamori, Y. [National Institute for Environmental Studies, Tsukuba (Japan); Sudo, R. [Tohoku University, Sendai (Japan). Faculty of Engineering; Kurihara, Y. [Ou Univ., Fukushima (Japan). Faculty of Engineering; Matsumura, M. [University of Tsukuba, Tsukuba (Japan). Institute of Applied Biochemical

    1997-11-10

    Microcosm system was applied to assess effect of anionic surfactant (LAS) on aquatic ecosystem. Anionic surfactant such as LAS was added to an flask microcosm consisting of four species of bacteria as decomposer, one species of ciliate protozoa (Cyclidium glaucoma), two rotifers (Philodina sp. and Lepadella sp.) and one aquatic oligochaete (Aeolosoma hemprichi) as predator, and a green alga (Chlorella sp.) and a filamentous blue-green alga (Tolypothrix sp.) as producer, comparing with that of an natural lake model ecosystem derived from natural lake water. In the flask microcosm system and the natural lake model ecosystem, biodegradation rates of LAS were almost same and NOECs (no observed effect concentration) of LAS were also below 1.5 mg{center_dot} l{sup -1}. It was found that flask microcosm test could provide precise ecological effect assessment of LAS on number of microorganisms because the system showed higher reproducibility and stability than natural take model ecosystem. It was suggested that flask microcosm test was useful ecological effect assessment method which can reflect natural aquatic ecosystem. 10 refs., 4 figs., 2 tabs.

  8. Interactive effects among ecosystem services and management practices on crop production: pollination in coffee agroforestry systems.

    Science.gov (United States)

    Boreux, Virginie; Kushalappa, Cheppudira G; Vaast, Philippe; Ghazoul, Jaboury

    2013-05-21

    Crop productivity is improved by ecosystem services, including pollination, but this should be set in the context of trade-offs among multiple management practices. We investigated the impact of pollination services on coffee production, considering variation in fertilization, irrigation, shade cover, and environmental variables such as rainfall (which stimulates coffee flowering across all plantations), soil pH, and nitrogen availability. After accounting for management interventions, bee abundance improved coffee production (number of berries harvested). Some management interventions, such as irrigation, used once to trigger asynchronous flowering, dramatically increased bee abundance at coffee trees. Others, such as the extent and type of tree cover, revealed interacting effects on pollination and, ultimately, crop production. The effects of management interventions, notably irrigation and addition of lime, had, however, far more substantial positive effects on coffee production than tree cover. These results suggest that pollination services matter, but managing the asynchrony of flowering was a more effective tool for securing good pollination than maintaining high shade tree densities as pollinator habitat. Complex interactions across farm and landscape scales, including both management practices and environmental conditions, shape pollination outcomes. Effective production systems therefore require the integrated consideration of management practices in the context of the surrounding habitat structure. This paper points toward a more strategic use of ecosystem services in agricultural systems, where ecosystem services are shaped by the coupling of management interventions and environmental variables.

  9. Evaluation of Heavy Metal Contamination Ecological Risk in a Food-Producing Ecosystem

    Directory of Open Access Journals (Sweden)

    mohsen Mirzaei

    2017-09-01

    Full Text Available Introduction and purpose: The consumption of agricultural products cultivated in soils contaminated with heavy metals is very health-threatening. Therefore, the implementation of an inclusive and multilateral assessment of the heavy metal risk on the verge of their entrance to the food chain is a matter of fundamental importance. Regarding this, the present study was conducted with the aim of monitoring the concentration of heavy metals in the surface soil of grape gardens and zoning the area in terms of geoaccumulation index (Igeo, contamination factor, degree of contamination, modified degree of contamination (MDC, pollution load index (PLI, and ecological risk index (RI. Methods: For the purpose of the study, 31 grape gardens were selected in Gahru region (i.e., the main center of grape production through simple random sampling technique. The surface soil samples were transferred to the laboratory for the analysis of the concentration of cadmium, lead, chromium, copper, and zinc. Results: According to the results, the concentration of the metals in the region was Zn > Cu > Pb > Cr > Cd with the mean total concentrations of 74.87, 55.31, 22.32, 9.81, and 0.91 mg/kg, respectively. Based on the results of the PLI, six grape gardens were classified as insignificantly contaminated (1≤PLI≤2, and the remaining gardens were classified as noncontaminated (PLI300, medium (150

  10. The chemical behaviour and ecological transfer in the human food chain of some radionuclides in aqueous ecosystems

    International Nuclear Information System (INIS)

    Furnica, Gh.

    1980-01-01

    The aqueous ecosystem of the Danube has been investigated in the period of 1976-1979. Data on the ecological transfer of radionuclides in the human food chain made an estimation available on the risk of the affected population. In the assessment of population exposure, the internal radiation dose for a period of one year and the continuous external irradiation determined by TLD have been considered. - The results revealed very low Sr-90 and Cs-137 contents in the Danube water and in the drinking water. The radioactivity contents are higher in the sediment and in some biota than in the water. The H-3 content in the Danube water varies in a wider range and higher concentration was found in fish than in the water. Both the Danube sediment and the irrigated sandy soil contain very low concentrations of fission products. During 1976-1979, the radioiodine content in air, milk and cow thyroid around the 679-Km is continuously decreasing. - Based on the data obtained, the corresponding collective dose equivalent value was calculated and the risk on the health of the population was found to be very low from contamination during 1975-1978. The radioactivity concentration values in critical human food chain, however, are not negligible. (author)

  11. Forbidden versus permitted interactions: Disentangling processes from patterns in ecological network analysis.

    Science.gov (United States)

    Strona, Giovanni; Veech, Joseph A

    2017-07-01

    Several studies have identified the tendency for species to share interacting partners as a key property to the functioning and stability of ecological networks. However, assessing this pattern has proved challenging in several regards, such as finding proper metrics to assess node overlap (sharing), and using robust null modeling to disentangle significance from randomness. Here, we bring attention to an additional, largely neglected challenge in assessing species' tendency to share interacting partners. In particular, we discuss and illustrate with two different case studies how identifying the set of "permitted" interactions for a given species (i.e. interactions that are not impeded, e.g. by lack of functional trait compatibility) is paramount to understand the ecological and co-evolutionary processes at the basis of node overlap and segregation patterns.

  12. Utilization and control of ecological interactions in polymicrobial infections and community-based microbial cell factories.

    Science.gov (United States)

    Wigneswaran, Vinoth; Amador, Cristina Isabel; Jelsbak, Lotte; Sternberg, Claus; Jelsbak, Lars

    2016-01-01

    Microbial activities are most often shaped by interactions between co-existing microbes within mixed-species communities. Dissection of the molecular mechanisms of species interactions within communities is a central issue in microbial ecology, and our ability to engineer and control microbial communities depends, to a large extent, on our knowledge of these interactions. This review highlights the recent advances regarding molecular characterization of microbe-microbe interactions that modulate community structure, activity, and stability, and aims to illustrate how these findings have helped us reach an engineering-level understanding of microbial communities in relation to both human health and industrial biotechnology.

  13. Impact of the Qualitative and Quantitative Aspects of Human Activity on the Ecosystem: Demonstration through the Use of Ecological Footprint Approach

    Directory of Open Access Journals (Sweden)

    Makram GAALICHE

    2012-12-01

    Full Text Available This article aims to show that the impact of human activities on the ecosystem, measured by the Ecological Footprint, depends on the qualitative and quantitative aspects of the population. Indeed, we confirmed our hypothesis by an empirical analysis on Tunisia, where it was revealed that the increase in its Ecological Footprint, is attributed mainly to massive consumption of goods, bad land management by building horizontal, and to a lesser extent, to the presence of polluting employments. The results suggest the adoption of targeted policies, according to the specific characteristics of population.

  14. A model using marginal efficiency of investment to analyse carbon and nitrogen interactions in forested ecosystems

    Science.gov (United States)

    Thomas, R. Q.; Williams, M.

    2014-12-01

    Carbon (C) and nitrogen (N) cycles are coupled in terrestrial ecosystems through multiple processes including photosynthesis, tissue allocation, respiration, N fixation, N uptake, and decomposition of litter and soil organic matter. Capturing the constraint of N on terrestrial C uptake and storage has been a focus of the Earth System modelling community. Here we explore the trade-offs and sensitivities of allocating C and N to different tissues in order to optimize the productivity of plants using a new, simple model of ecosystem C-N cycling and interactions (ACONITE). ACONITE builds on theory related to plant economics in order to predict key ecosystem properties (leaf area index, leaf C:N, N fixation, and plant C use efficiency) based on the optimization of the marginal change in net C or N uptake associated with a change in allocation of C or N to plant tissues. We simulated and evaluated steady-state and transient ecosystem stocks and fluxes in three different forest ecosystems types (tropical evergreen, temperate deciduous, and temperate evergreen). Leaf C:N differed among the three ecosystem types (temperate deciduous database describing plant traits. Gross primary productivity (GPP) and net primary productivity (NPP) estimates compared well to observed fluxes at the simulation sites. A sensitivity analysis revealed that parameterization of the relationship between leaf N and leaf respiration had the largest influence on leaf area index and leaf C:N. Also, a widely used linear leaf N-respiration relationship did not yield a realistic leaf C:N, while a more recently reported non-linear relationship simulated leaf C:N that compared better to the global trait database than the linear relationship. Overall, our ability to constrain leaf area index and allow spatially and temporally variable leaf C:N can help address challenges simulating these properties in ecosystem and Earth System models. Furthermore, the simple approach with emergent properties based on

  15. Illustrating the Interaction of Nature and People in Ecosystem Services: The Case of Terroir in Wine

    Science.gov (United States)

    Nicholas, K. A.

    2014-12-01

    The ecosystem services (ES) approach is increasingly used in research and policy, with the Common International Framework on Ecosystem Services (CICES) "cascade" gaining traction as a framework for conceptualizing the production of ecosystem services by the natural environment, and then people consuming these services and obtaining benefits depending on their values. However, uptake of the ES concept on the ground by ecosystem managers, and understanding by everyday citizens, is still limited. One barrier is the challenge of providing tangible, examples of everyday benefits and values that people can readily connect with the biophysical structures and functions that underlie their provision. Winegrowing offers one promising case to illustrate the linkages all along the chain of production and consumption of ecosystem services. The sensitive winegrape has long been known for its properties of terroir, where the taste of wine reflects the environmental conditions of the place where it is grown, a feature valued by consumers. Here the CICES framework is illustrated with the case of winegrowing, demonstrating that the current linear model of natural production and human consumption of ES needs to be modified for this case because people influence each of the five stages by shaping and responding to their environment, producing a two-way interaction between people and the environment throughout. For example, while natural drivers such as climate and soils are key to the provision of the service of winegrape yields, landowners modify the biophysical environment through site selection and growers modify plant ecophysiological function through farming practices such as pruning and irrigation in order to influence the final service. Similarly, winemakers' expertise is needed to transform the service of winegrape yields into the product of wine that can be enjoyed and valued by consumers, whose preferences shape wine styles as well. This case illustrates how incorporating

  16. Using a social-ecological systems perspective to understand tourism and landscape interactions in coastal areas

    Directory of Open Access Journals (Sweden)

    Jasper Hessel Heslinga

    2017-04-01

    Full Text Available Purpose – The purpose of this paper is to look at the potential synergies between tourism and landscapes and examine the potential contribution of tourism to build social-ecological resilience in the Dutch Wadden. Design/methodology/approach – The authors reveal how a social-ecological systems perspective can be used to conceptualize the Wadden as a coupled and dynamic system. This paper is a conceptual analysis that applies this approach to the Dutch Wadden. The data used for the inquiry primarily comes from a literature review. Findings – The authors argue that the social-ecological systems perspective is a useful approach and could be used to improve the governance of multi-functional socio-ecological systems in coastal areas. Opportunities for synergies between tourism and landscapes have been overlooked. The authors consider that tourism and nature protection are potentially compatible and that the synergies should be identified. Research limitations/implications – This paper is only a conceptual application rather than an empirical case study. Further research to actually apply the methodology is needed. Practical implications – Managers of protected areas should consider applying a social-ecological systems approach. Social implications – The views of a wide variety of stakeholders should be considered in landscape planning. Originality/value – The value of this paper lies in the articulation of the social-ecological systems perspective as a way to identify and understand the complex interactions between tourism and landscape, and the potential synergies between them.

  17. Ecological dynamics and complex interactions of Agrobacterium megaplasmids.

    Science.gov (United States)

    Platt, Thomas G; Morton, Elise R; Barton, Ian S; Bever, James D; Fuqua, Clay

    2014-01-01

    As with many pathogenic bacteria, agrobacterial plant pathogens carry most of their virulence functions on a horizontally transmissible genetic element. The tumor-inducing (Ti) plasmid encodes the majority of virulence functions for the crown gall agent Agrobacterium tumefaciens. This includes the vir genes which drive genetic transformation of host cells and the catabolic genes needed to utilize the opines produced by infected plants. The Ti plasmid also encodes, an opine-dependent quorum sensing system that tightly regulates Ti plasmid copy number and its conjugal transfer to other agrobacteria. Many natural agrobacteria are avirulent, lacking the Ti plasmid. The burden of harboring the Ti plasmid depends on the environmental context. Away from diseased hosts, plasmid costs are low but the benefit of the plasmid is also absent. Consequently, plasmidless genotypes are favored. On infected plants the costs of the Ti plasmid can be very high, but balanced by the opine benefits, locally favoring plasmid bearing cells. Cheating derivatives which do not incur virulence costs but can benefit from opines are favored on infected plants and in most other environments, and these are frequently isolated from nature. Many agrobacteria also harbor an At plasmid which can stably coexist with a Ti plasmid. At plasmid genes are less well characterized but in general facilitate metabolic activities in the rhizosphere and bulk soil, such as the ability to breakdown plant exudates. Examination of A. tumefaciens C58, revealed that harboring its At plasmid is much more costly than harboring it's Ti plasmid, but conversely the At plasmid is extremely difficult to cure. The interactions between these co-resident plasmids are complex, and depend on environmental context. However, the presence of a Ti plasmid appears to mitigate At plasmid costs, consistent with the high frequency with which they are found together.

  18. Coupled economic-ecological models for ecosystem-based fishery management: Exploration of trade-offs between model complexity and management needs

    DEFF Research Database (Denmark)

    Thunberg, Eric; Holland, Dan; Nielsen, J. Rasmus

    2012-01-01

    Ecosystem based fishery management has moved beyond rhetorical statements calling for a more holistic approach to resource management, to implementing decisions on resource use that are compatible with goals of maintaining ecosystem health and resilience. Coupled economic-ecological models...... are a primary tool for informing these decisions. Recognizing the importance of these models, the International Council for the Exploration of the Seas (ICES) formed a Study Group on Integration of Economics, Stock Assessment and Fisheries Management (SGIMM) to explore alternative modelling approaches...... and ecological systems are inherently complex, models are abstractions of these systems incorporating varying levels of complexity depending on available data and the management issues to be addressed. The objective of this special session was to assess the pros and cons of increasing model complexity...

  19. Linking niche theory to ecological impacts of successful invaders: insights from resource fluctuation-specialist herbivore interactions.

    Science.gov (United States)

    Gidoin, Cindy; Roques, Lionel; Boivin, Thomas

    2015-03-01

    Theories of species coexistence and invasion ecology are fundamentally connected and provide a common theoretical framework for studying the mechanisms underlying successful invasions and their ecological impacts. Temporal fluctuations in resource availability and differences in life-history traits between invasive and resident species are considered as likely drivers of the dynamics of invaded communities. Current critical issues in invasion ecology thus relate to the extent to which such mechanisms influence coexistence between invasive and resident species and to the ability of resident species to persist in an invasive-dominated ecosystem. We tested how a fluctuating resource, and species trait differences may explain and help predict long-term impacts of biological invasions in forest specialist insect communities. We used a simple invasion system comprising closely related invasive and resident seed-specialized wasps (Hymenoptera: Torymidae) competing for a well-known fluctuating resource and displaying divergent diapause, reproductive and phenological traits. Based on extensive long-term field observations (1977-2010), we developed a combination of mechanistic and statistical models aiming to (i) obtain a realistic description of the population dynamics of these interacting species over time, and (ii) clarify the respective contributions of fluctuation-dependent and fluctuation-independent mechanisms to long-term impact of invasion on the population dynamics of the resident wasp species. We showed that a fluctuation-dependent mechanism was unable to promote coexistence of the resident and invasive species. Earlier phenology of the invasive species was the main driver of invasion success, enabling the invader to exploit an empty niche. Phenology also had the greatest power to explain the long-term negative impact of the invasive on the resident species, through resource pre-emption. This study provides strong support for the critical role of species

  20. Addressing ecological effects of radiation on populations and ecosystems to improve protection of the environment against radiation: Agreed statements from a Consensus Symposium

    OpenAIRE

    Bréchignac, François; Oughton, Deborah; Mays, Claire; Barnthouse, Lawrence; Beasley, James C.; Bonisoli-Alquati, Andrea; Bradshaw, Clare; Brown, Justin; Dray, Stéphane; Geras'kin, Stanislav; Glenn, Travis; Higley, Kathy; Ishida, Ken; Kapustka, Lawrence; Kautsky, Ulrik

    2016-01-01

    This paper reports the output of a consensus symposium organized by the International Union of Radioecology in November 2015. The symposium gathered an academically diverse group of 30 scientists to consider the still debated ecological impact of radiation on populations and ecosystems. Stimulated by the Chernobyl and Fukushima disasters? accidental contamination of the environment, there is increasing interest in developing environmental radiation protection frameworks. Scientific research c...

  1. Longitudinal patterns and response lengths of algae in riverine ecosystems: A model analysis emphasising benthic-pelagic interactions.

    Science.gov (United States)

    Jäger, Christoph G; Borchardt, Dietrich

    2018-04-07

    In riverine ecosystems primary production is principally possible in two habitats: in the benthic layer by sessile algae and in the surface water by planktonic algae being transported downstream. The relevance of these two habitats generally changes along the rivers' continuum. However, analyses of the interaction of algae in these two habitats and their controlling factors in riverine ecosystems are, so far, very rare. We use a simplified advection-diffusion model system combined with ecological process kinetics to analyse the interaction of benthic and planktonic algae and nutrients along idealised streams and rivers at regional to large scales. Because many of the underlying processes affecting algal dynamics are influenced by depth, we focus particularly on the impact of river depth on this interaction. At constant environmental conditions all state variables approach stable spatial equilibria along the river, independent of the boundary conditions at the upstream end. Because our model is very robust against changes of turbulent diffusion and stream velocity, these spatial equilibria can be analysed by a simplified or