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At least 19 recordsLinked to original sources
PubMed2004

[Ecosystem approach: a new concept for ecosystem management].

Ecosystem approach (EA) was firstly proposed by ecologists in developed countries and then supported by a number of international institutions and NGOs, among which, CBD, IUCN and WWF played important roles. Ecosystem approach is an integrated strategy for the management of land, soil and bio-resources. The application of EA will help to reach a balance between conservation, sustainable use, and fair and equitable sharing of the benefits arising out of the utilization of biological resources. Ecosystem approach is a methodology of ecosystem management, focusing on the biological organisms and recognising that human beings, with their cultural diversity, are an integral component of many ecosystems. The decision V/6 adopted by the Conference of the Parties to the CBD at its fifth meeting in 2000 concretized the EA in the form of twelve principles and five operational guidelines. Our government has recently made a lot of efforts in ecosystem management at large scale with many important measures and obtained significant achievements, but the potential role of local governments, institutions and individuals has not been fully played. In the attempts of managing a specific ecosystem, there are many successful cases done by our ecologists, for example, the ecological management of Chinese fir plantation forest in central subtropical China. However, the whole ecosystem at national or regional level is confronted with a lot of serious problems, mainly because there is a lack of complete understanding of the significance of ecosystem management and a lack of guidelines or principles from an integrated scientific theory. The introduction and implementation of ecosystem approach will play an important role in improving the ecosystem management in China.

China↗
PubMed2003

Spatial pattern of ecosystem function and ecosystem conservation.

The spatial pattern of ecosystem function can affect ecosystem conservation. Ecosystem functions are often heterogeneous spatially due to physical and biological factors. We can influence ecosystem functions by changing the spatial patterns of the physical and biological elements of an ecosystem and regulating their combinations. The variation-position effect highlights a phenomenon resulting from the spatial pattern of ecosystem function. The effect shows that the identical variation of a factor may produce different effects on the over-all situation when this variation occurs in a different spatial position. In a watershed of the Yangtze River, water retention is a primary ecosystem function. The variation-position effect for water retention capacity occurs in the watershed because of the spatial heterogeneity in vegetation, soil, and slope. The change of vegetation that occurs in a complex can affect the overall situation of water retention, and the effect can be different due to the change occurring in the position holding different vegetation-soil-slope complex. To improve the ecosystem in the watershed and to meet the social needs for the ecosystem function of water retention, a strategy called "ecosystem function and spatial pattern-based forest extension" was proposed to conserve forests. The implementation of the strategy enables the watershed to attain the maximum effective increase in water retention capacity.

Conservation of Natural Resources↗
PubMed2001

Closed Artificial ecosystems as a means of ecosystem studies for Earth and space needs.

Closed Artificial ecosystems (CAES) have good prospects for wide use as new means for quantitative studies of different types of both natural ecosystems and man-made ones. The paper deals with the discussion of three points of CAES applications. The first one is of importance for theoretical ecology development and is connected with bringing together "holistic" and "merological" approaches in ecosystems studies. Using CAES, we can combine both approaches, taking into account the biotic turnover of limiting substrates which few in number even for complicated natural ecosystems. The second CAES use concerns the development of "ecosystems health" concept and application of a key-factor-approach for the indication and measurement of healthy unhealthy state and functioning of ecosystems or their links. The third use is more of an applied nature, oriented to the intensification of bioremediation or biodepollution processes in different types of ecosystems, including the global biosphere. Grant numbers: N 99-04-96017, N25.

Biodegradation, Environmental↗
PubMed1999

Sustaining Ecosystem Services in Human-Dominated Watersheds: Biohydrology and Ecosystem Processes in the South Platte River Basin.

/ Sustaining ecosystem services important to humans while providing a dependable water supply for agriculture and urban needs is a major challenge faced by managers of human-dominated watersheds. Modification of natural flow regimes alters the abundance and composition of native plant and animal communities, affecting ecosystem services such as water storage and nutrient cycling that depend on particular species or functional groups. Because complete restoration of natural hydrology is generally not an option in human-dominated watersheds, there is a need to determine which specific flow manipulations are necessary to restore species-dependent ecosystem services in particular systems. Here we propose a framework for predicting ecological consequences of flow manipulations that is based on the role of hydrology in linking population, community, and ecosystem processes. We use a case-study approach to examine how interactions among the flow regime and species' functional traits help organize local biotic communities and generate alternate states of ecosystem functioning. Results indicate the importance of integrating hydrology and biology to predict ecological consequences of flow regime manipulations and the need to apply general flow-restoration principles on a case-by-case basis.KEY WORDS: Biohydrology; Aquatic ecosystems; Community assembly; Ecological integrity; Watershed restoration; Ecosystem serviceshttp://link.springer-ny.com/link/service/journals/00267/bibs/24n1p39.html

Journal Article↗
PubMed1991

A toxicological perspective on ecosystem characteristics to track sustainable development. VII. Ecosystem health.

"Ecosystem health," an emerging science paralleling human and veterinary medicine, has as its goals the systematic diagnosis and treatment of stressed ecosystems. Ecosystems are stressed by physical factors such as boat traffic, biological factors such as introduction of an exotic species, and chemical factors such as pH change. Even if these classes of stressors affect the same trophic levels, the resulting ecosystem disease states have different etiologies because the stress is introduced and propagated by different mechanisms. This paper presents a toxicological perspective on ecosystem sustainability. I discuss how classical toxicological concepts have to be modified when the experimental unit is an ecosystem. When exposures are high, effects are acute and are often measurable (e.g., fish kill). However, when exposures are low and chronic, effects are often hard to separate from the background. Evidence of high risk for lack of sustainable development is the exceeding of ecosystem "threshold criteria."

Biomarkers↗
PubMed1994

Genetic information and ecosystem health: arguments for the application of chaos theory to identify boundary conditions for ecosystem management.

To meet the demands for goods and services of an exponentially growing human population, global ecosystems will come under increasing human management. The hallmark of successful ecosystem management will be long-term ecosystem stability. Ecosystems and the genetic information and processes which underlie interactions of organisms with the environment in populations and communities exhibit behaviors which have nonlinear characteristics. Nonlinear mathematical formulations describing deterministic chaos have been used successfully to model such systems in physics, chemistry, economics, physiology, and epidemiology. This approach can be extended to ecotoxicology and can be used to investigate how changes in genetic information determine the behavior of populations and communities. This article seeks to provide the arguments for such an approach and to give initial direction to the search for the boundary conditions within which lies ecosystem stability. The identification of a theoretical framework for ecotoxicology and the parameters which drive the underlying model is a critical component in the formulation of a prioritized research agenda and appropriate ecosystem management policy and regulation.

Ecosystem↗
PubMedDate not supplied

A new coastal marine ecosystem model study coupled with hydrodynamics and tidal flat ecosystem effect.

A new coastal marine ecosystem model was developed, which was composed of pelagic and benthic ecosystems, and was applied to Mikawa Bay, Japan. This model deals with variations of biochemical and physical interactions among dissolved oxygen and C-N-P species (composition formed out of carbon, nitrogen and phosphorus elements) so that it resolves the flux dynamics of carbon, nitrogen, phosphorus and oxygen elements. The physical and biochemical mechanism figured in this model is constructed for the purpose of simulating the estuarine lower trophic ecosystem, in areas where the sea was too deep for light to reach the sea-bottom. As a result of coupling the benthic with pelagic system, the effect of process of sedimentation and nutrient diffusion back to the pelagic system could be indicated. In addition, by implementing the tidal flat ecosystem model's calculation result, the integrated model can include the effect of water purification in tidal flats where the light can reach the sea-bottom, and where seaweed, sea grass and benthic algae exist. In this study, the model indicates that oxygen-depleted water exists at the sea-bottom especially in summer mainly caused by an increase of oxygen consumption in the benthic system and a decrease of the vertical mixing water process. Furthermore, by comparing the case--with the tidal flat ecosystem model and the case without it, the effect of water purification of tidal flat estuaries was indicated. From the viewpoint of a short time scale, the tidal flat has the potential to restrict red tide (rapid increase of phytoplankton), and from the viewpoint of a long time scale, it restricts the sedimentation of detritus. Restricting the sedimentation prevents oxygen-depleted water occurring in the coastal marine system of Mikawa Bay.

Ecosystem↗
PubMed2006

A framework for community and ecosystem genetics: from genes to ecosystems.

Can heritable traits in a single species affect an entire ecosystem? Recent studies show that such traits in a common tree have predictable effects on community structure and ecosystem processes. Because these 'community and ecosystem phenotypes' have a genetic basis and are heritable, we can begin to apply the principles of population and quantitative genetics to place the study of complex communities and ecosystems within an evolutionary framework. This framework could allow us to understand, for the first time, the genetic basis of ecosystem processes, and the effect of such phenomena as climate change and introduced transgenic organisms on entire communities.

Animals↗
PubMed2005

Measuring conditions and trends in ecosystem services at multiple scales: the Southern African Millennium Ecosystem Assessment (SAfMA) experience.

The Southern African Millennium Ecosystem Assessment (SAfMA) evaluated the relationships between ecosystem services and human well-being at multiple scales, ranging from local through to sub-continental. Trends in ecosystem services (fresh water, food, fuel-wood, cultural and biodiversity) over the period 1990-2000 were mixed across scales. Freshwater resources appear strained across the continent with large numbers of people not securing adequate supplies, especially of good quality water. This translates to high infant mortality patterns across the region. In some areas, the use of water resources for irrigated agriculture and urban-industrial expansion is taking place at considerable cost to the quality and quantity of freshwater available to ecosystems and for domestic use. Staple cereal production across the region has increased but was outstripped by population growth while protein malnutrition is on the rise. The much-anticipated wood-fuel crisis on the subcontinent has not materialized but some areas are experiencing shortages while numerous others remain vulnerable. Cultural benefits of biodiversity are considerable, though hard to quantify or track over time. Biodiversity resources remain at reasonable levels, but are declining faster than reflected in species extinction rates and appear highly sensitive to land-use decisions. The SAfMA sub-global assessment provided an opportunity to experiment with innovative ways to assess ecosystem services including the use of supply-demand surfaces, service sources and sink areas, priority areas for service provision, service 'hotspots' and trade-off assessments.

Agriculture↗
PubMed2006

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

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

Animals↗
PubMed2001

Multicompartment ecosystem mass balances as a tool for understanding and managing the biogeochemical cycles of human ecosystems.

Nitrogen remains a ubiquitous pollutant in surface and groundwater throughout the United States, despite 30 years of pollution control efforts. A detailed multicompartment N balance for the Central Arizona-Phoenix ecosystem is used to illustrate how an ecosystem-level approach can be used to develop improved N management strategies. The N balance is used to demonstrate how nitrate in pumped groundwater used for crop irrigation could be used to reduce inputs of commercial fertilizer and decrease N leaching to aquifers. Effectively managing N pollution also will require an understanding of the complex factors that control the N balance, including targeted regulations, individual human behavior, land-use conversion, and other ecosystem management practices that affect the N balance. These sometimes countervailing factors are illustrated with several scenarios of wastewater treatment technology and population growth in the Phoenix area. Management of N eventually must be coupled to management of other elements, notably carbon, phosphorus, and salts. We postulate that an ecosystem framework for pollution management will result in strategies that are more effective, fairer, and less expensive than current approaches.

Arizona↗
PubMed2005

Links between tree species, symbiotic fungal diversity and ecosystem functioning in simplified tropical ecosystems.

We studied the relationships among plant and arbuscular mycorrhizal (AM) fungal diversity, and their effects on ecosystem function, in a series of replicate tropical forestry plots in the La Selva Biological Station, Costa Rica. Forestry plots were 12 yr old and were either monocultures of three tree species, or polycultures of the tree species with two additional understory species. Relationships among the AM fungal spore community, host species, plant community diversity and ecosystem phosphorus-use efficiency (PUE) and net primary productivity (NPP) were assessed. Analysis of the relative abundance of AM fungal spores found that host tree species had a significant effect on the AM fungal community, as did host plant community diversity (monocultures vs polycultures). The Shannon diversity index of the AM fungal spore community differed significantly among the three host tree species, but was not significantly different between monoculture and polyculture plots. Over all the plots, significant positive relationships were found between AM fungal diversity and ecosystem NPP, and between AM fungal community evenness and PUE. Relative abundance of two of the dominant AM fungal species also showed significant correlations with NPP and PUE. We conclude that the AM fungal community composition in tropical forests is sensitive to host species, and provide evidence supporting the hypothesis that the diversity of AM fungi in tropical forests and ecosystem NPP covaries.

Biodiversity↗
PubMed2004

Communication in ecosystem management: a case study of cross-disciplinary integration in the assessment phase of the interior Columbia Basin Ecosystem Management Project.

Effective communication is essential to the success of collaborative ecosystem management projects. In this paper, we investigated the dynamics of the Interior Columbia Basin Ecosystem Management Project's (ICBEMP) cross-disciplinary integration process in the assessment phase. Using a case study research design, we captured the rich trail of experience through conducting in-depth interviews and collecting information from internal and public documents, videos, and meetings related to the ICBEMP. Coding and analysis was facilitated by a qualitative analysis software, NVivo. Results include the range of internal perspectives on barriers and facilitators of cross-disciplinary integration in the Science Integration Team (SIT). These are arrayed in terms of discipline-based differences, organizational structures and activities, individual traits of scientists, and previous working relationships. The ICBEMP organization included a team of communication staffs (CT), and the data described the CT as a mixed group in terms of qualifications and educational backgrounds that played a major role in communication with actors external to the ICBEMP organization but a minor one in terms of internal communication. The data indicated that the CT-SIT communication was influenced by characteristics of actors and structures related to organizations and their cultures. We conclude that the ICBEMP members may not have had a sufficient level of shared understanding of central domains, such as the task at hand and ways and timing of information sharing. The paper concludes by suggesting that future ecosystem management assessment teams use qualified communications specialists to design and monitor the development of shared cognition among organization members in order to improve the effectiveness of communication and cross-disciplinary integration.

Communication↗
PubMed1989

Ecosystem health. II. Quantifying and predicting ecosystem effects of toxic chemicals: can mammalian testing be used for lab-to-field and field-to-lab extrapolations?

An understanding of the "health" of an ecosystem after exposure to toxic chemicals can be achieved through studies which concentrate on the description of effects on ecosystem homeostasis, identification of disruption, and determination of pathways between these. Studies using native mammals to determine effects of toxicants on terrestrial ecosystems must be designed so that they identify the populations at risk, select appropriate biological effect endpoints, and obtain appropriate numbers and types of samples and contextual ecological data. Accompanying laboratory studies are often needed to complement or confirm observations from the field. Although aquatic biologists routinely use about 10 selected native species for toxicological work, terrestrial biologists seem to prefer using laboratory mammals in "ecotoxicological" studies. Some have advocated using only laboratory rodents in a field setting, while others have suggested using both laboratory mammals and native species. We take the position that there are considerable limitations in the use of laboratory rodents in toxicological studies which purport to be meaningful with regard to prediction of toxicant-induced effects on ecological systems. Nevertheless, we are able to suggest an integrated plan that includes the systematic monitoring of native species in conjunction with laboratory animals exposed in the laboratory and in the field.

Animals↗
PubMed1998

Net ecosystem productivity, net primary productivity and ecosystem carbon sequestration in a Pinus radiata plantation subject to soil water deficit.

Tree carbon (C) uptake (net primary productivity excluding fine root turnover, NPP') in a New Zealand Pinus radiata D. Don plantation (42 degrees 52' S, 172 degrees 45' E) growing in a region subject to summer soil water deficit was investigated jointly with canopy assimilation (A(c)) and ecosystem-atmosphere C exchange rate (net ecosystem productivity, NEP). Net primary productivity was derived from biweekly stem diameter growth measurements using allometric relations, established after selective tree harvesting, and a litterfall model. Estimates of A(c) and NEP were used to drive a biochemically based and environmentally constrained model validated by seasonal eddy covariance measurements. Over three years with variable rainfall, NPP' varied between 8.8 and 10.6 Mg C ha(-1) year(-1), whereas A(c) and NEP were 16.9 to 18.4 Mg C ha(-1) year(-1) and 5.0-7.2 Mg C ha(-1) year(-1), respectively. At the end of the growing season, C was mostly allocated to wood, with nearly half (47%) to stems and 27% to coarse roots. On an annual basis, the ratio of NEP to stand stem volume growth rate was 0.24 +/- 0.02 Mg C m(-3). The conservative nature of this ratio suggests that annual NEP can be estimated from forest yield tables. On a biweekly basis, NPP' repeatedly lagged A(c), suggesting the occurrence of intermediate C storage. Seasonal NPP'/A(c) thus varied between nearly zero and one. On an annual basis, however, NPP'/A(c) was 0.54 +/- 0.03, indicating a conservative allocation of C to autotrophic respiration. In the water-limited environment, variation in C sequestration rate was largely accounted for by a parameter integrative for changes in soil water content. The combination of mensurational data with canopy and ecosystem C fluxes yielded an estimate of heterotrophic respiration (NPP' - NEP) approximately 30% of NPP' and approximately 50% of NEP. The estimation of fine-root turnover rate is discussed.

Journal Article↗
PubMed2004

Natural-product diversity of the New Caledonian marine ecosystem compared to other ecosystems: a pharmacologically oriented view.

In comparison with other ecosystems, biodiversity and natural-product diversity of the New Caledonian marine ecosystem, comprising lagoons, barrier reefs, and deep waters in seamount regions, are described here phylogenetically with the aid of molecular drawings and tabulation of data. Admittedly, since the inception of these studies in 1977, the comparison is biased by selection of New Caledonian organisms on the basis of positive pharmacologically oriented bioassays. However, we show that these and other distortions must be accepted to draw any comparison on a regional basis, which, nonetheless, turn out to be useful for the progress of knowledge, particularly in directing future explorations of biodiversity in the search for new pharmacologically active metabolites.

Animals↗
PubMed2006

A review of the Northern Ecosystem Initiative in Arctic Canada: facilitating arctic ecosystem research through traditional and novel approaches.

The Canadian Arctic is undergoing considerable social and environmental change. Anthropogenic stressors on this sensitive environment include climate change, contaminants, resource extraction, tourism and increasing human populations. The Northern Ecosystem Initiative (NEI) is a program aimed at supporting the sustainability of northern communities, and at improving our understanding of how northern ecosystems respond to these environmental stressors. A key element of the NEI is to establish partnerships between all levels of government, non-governmental environmental agencies, and northern residents. The NEI is an important source of financial support critical for social and environmental scientists as well as northern residents and their community and regional organizations. Initiated in 1998, the NEI has supported numerous northern scientific and capacity-building projects, and has evaluated the information gained from this work to refine and focus its future support to address key information gaps and northern needs.

Arctic Regions↗