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1.
Climate impacts on coastal and estuarine systems take many forms and are dependent on the local conditions, including those set by humans. We use a biocomplexity framework to provide a perspective of the consequences of climate change for coastal wetland ecogeomorphology. We concentrate on three dimensions of climate change affects on ecogeomorphology: sea level rise, changes in storm frequency and intensity, and changes in freshwater, sediment, and nutrient inputs. While sea level rise, storms, sedimentation, and changing freshwater input can directly impact coastal and estuarine wetlands, biological processes can modify these physical impacts. Geomorphological changes to coastal and estuarine ecosystems can induce complex outcomes for the biota that are not themselves intuitively obvious because they are mediated by networks of biological interactions. Human impacts on wetlands occur at all scales. At the global scale, humans are altering climate at rapid rates compared to the historical and recent geological record. Climate change can disrupt ecological systems if it occurs at characteristic time scales shorter than ecological system response and causes alterations in ecological function that foster changes in structure or alter functional interactions. Many coastal wetlands can adjust to predicted climate change, but human impacts, in combination with climate change, will significantly affect coastal wetland ecosystems. Management for climate change must strike a balance between that which allows pulsing of materials and energy to the ecosystems and promotes ecosystem goods and services, while protecting human structures and activities. Science-based management depends on a multi-scale understanding of these biocomplex wetland systems. Causation is often associated with multiple factors, considerable variability, feedbacks, and interferences. The impacts of climate change can be detected through monitoring and assessment of historical or geological records. Attribution can be inferred through these in conjunction with experimentation and modeling. A significant challenge to allow wise management of coastal wetlands is to develop observing systems that act at appropriate scales to detect global climate change and its effects in the context of the various local and smaller scale effects.  相似文献   

2.
River ecosystems are closely linked to human economic and social development, which are the most ecosystems at risk on earth. The research of ecosystem services can provide important scientific references for the ecosystems utilization,protection and management. On basis of summarizing the basic theories,assessment frameworks,technical methods and application practices related with research findings of river ecosystem services both at home and abroad,the existing shortcomings such as weak research foundation,lack of scientific and reasonable methods in ecosystem service evaluation,narrow application scope of the research results were pointed out. In consideration of the needs of society and the research tendency,the future developing directions of river ecosystems service were described: the solid research foundation should be established by multi-disciplinary and multi-scale integrations, the standardized,normalized and scientific evaluation system for ecosystem services shall be built by innovating assessment framework and technical methodology systems comprehensively, the new research areas including trade-offs and commercialization of ecosystem services will be carried out widely to expand our research perspectives and enhance the application values of the results.  相似文献   

3.
Salt marshes are an important transition zone between terrestrial and marine ecosystems, and in their natural state, they often function to cycle or trap terrestrially derived nutrients and organic matter. Many US salt marshes were ditched during the twentieth century, potentially altering their functionality. The goal of this 4-year study was to assess the impact of water from ditches within seven salt marshes on estuarine water quality and plankton communities within four estuaries on Long Island, NY, USA. We found that concentrations of inorganic nutrients (ammonium, phosphate), dissolved and particulate organic nitrogen and carbon (POC, PON, DOC, DON), and total coliform bacteria were significantly enriched in salt marsh ditches compared to the estuaries they discharged into. In addition, concentrations of ammonium and DON became more enriched in ditches as tidal levels decreased, suggesting these constituents were generated in situ. Quantification of nitrogen sources in Flanders Bay, NY, suggested salt marsh ditches could represent a substantial source of N to this estuary during summer months. Experimental incubations demonstrated that water from salt marsh ditches was capable of significantly enhancing the growth of multiple classes of phytoplankton, with large diatoms and dinoflagellates displaying the most dramatic increases in growth. Experiments further demonstrated that salt marsh ditchwater was capable of significantly enhancing pelagic respiration rates, suggesting discharge from ditches could influence estuarine oxygen consumption. In summary, this study demonstrates that tidal draining of salt marsh ditches is capable of degrading multiple aspects of estuarine water quality.  相似文献   

4.
Allometric laws and prediction in estuarine and coastal ecology   总被引:1,自引:0,他引:1  
A theoretical and quantitative framework of first principles would benefit estuarine and coastal ecologists in search of predictions to enhance our understanding and management of marine resources. The Metabolic Theory of Ecology describes a possible unifying theory for ecology, including mechanistically derived equations that predict scaling exponents observed in empirical, allometric relationships from individuals to ecosystems. The controversy surrounding this theory should stimulate our exploration of its potential use in the coastal realm, where questions specific to an applied science may suggest new refinements and derivations, contributing to the overall progress of ecology.  相似文献   

5.
Despite the widely acknowledged threat posed by invasive species in coastal estuaries, there are substantial gaps at the intersection of science and policy that are impeding invasive species management. In the face of pressing management needs in coastal and estuarine environments, we advocate that introduced species should receive the kind of management effort dedicated, for example, to reducing pollution. We support our argument with some examples of economic costs of estuarine and coastal introduced species and a summary of recent evidence for the ecological costs. We highlight some of the issues that either thwart or facilitate the successful marriage between science and management of introduced species, including the regulatory framework for management. We use the available information on coastal eradication programs, including case histories of the programs for Caulerpa taxifolia and Spartina alterniflora (and hybrids) in the western USA, to indicate the feasibility of managing introduced species and to help point out how management and science can improve the outcome. We close with a research agenda that focuses primarily on science that will really assist with invasive species management and reflects our own experience and the opinions of managers directly involved with this issue.  相似文献   

6.
喀斯特生态系统服务研究进展与展望   总被引:1,自引:1,他引:0  
韩会庆  苏志华 《中国岩溶》2017,36(3):352-358
喀斯特生态系统是全球典型的脆弱生态系统之一,它为人类提供了重要的服务功能和价值。回顾国内外喀斯特生态系统服务研究的文献可发现,当前研究多遵循“土地利用变化—生态系统服务价值响应”的研究范式,仅重视中小尺度喀斯特生态系统服务价值的空间异质性,强调土地利用变化和生态工程对生态系统服务价值的影响。而今后应加强基于“生态系统结构、过程—功能—服务”级联框架的喀斯特生态系统服务研究,构建喀斯特生态系统服务分类体系,突出大尺度喀斯特生态系统服务评估,拓展喀斯特生态系统服务之间权衡与协同及喀斯特生态系统服务对人类福祉的影响,定量分析自然和人为因素对喀斯特生态系统服务的影响。   相似文献   

7.
A conceptual model of estuarine freshwater inflow management   总被引:1,自引:0,他引:1  
As humans continue to influence the quantity, timing, and quality of freshwater input to estuaries, it is becoming increasingly common for policies to be enacted that mandate the establishment of freshwater inflow criteria that will serve to preserve and protect estuarine ecosystems. This paper reviews the scientific literature describing how changes in freshwater inflow affect estuaries, proposes a conceptual model that explores the roles of scientists, citizens, politicians, and managers in the management of freshwater inflow to estuaries, and uses the model to explore the ways in which freshwater inflow is managed in a variety of estuaries. The scientific review is organized to provide an overview of the connections between freshwater inflow (in terms of the quantity, quality, and timing of water delivery), estuarine conditions (such as salinity and concentrations of dissolved and particulate material), and estuarine resources (such as the distribution and abundance of organisms), and to highlight our understanding of the causative mechanisms that underlie the relationships among these variables. The premise of the conceptual model is that the goal of estuarine freshwater inflow policy is to protect those resources and functions that we as a society value in estuaries, and that management measures use scientific information about the relationships among inflow, conditions, and resources to establish inflow standards that can meet this goal. The management approach can be inflow-based (flow is kept within some prescribed bounds under the assumption that taking too much away is bad for the resources), condition-based (inflow standards are set in order to maintain specified conditions in the estuary), or resource-based (inflow standards are set based on the requirements of specific resources), but each of these is carried out by regulating inflow. This model is used as a framework to describe the development of freshwater inflow criteria for estuaries in Texas, Florida, and California.  相似文献   

8.
Numerous studies have concluded that better use of scientific information could improve the quality of coastal and estuarine environmental management. Approaches for effecting such a change include ecosystem-based, integrated, and adaptive management, but such basic re-orientation of estuarine and coastal management has proved difficult to achieve. Even environmental indicators, seemingly straightforward ways of injecting scientific information into decision making, have achieved broad on-the-ground use in relatively few instances—principally the largest estuary management programs. A conceptual framework useful for examining environmental management systems affecting the five PNCERS (Pacific Northwest coastal Ecosystems Regional Study) estuaries conceives of environmental managers, researchers, and interested and affected parties in the public as interacting through the multi-layered institutional arrangements that currently promote the utilization, management, or protection of coastal and estuarine resources. Considerable variation exists in the approach and effectiveness of the region's environmental management organizations. Interaction between science and management in the region appears to be limited to an extent by high transaction costs; a cultural divide between environmental scientists and environmental managers is perceived by members of both groups who work with the PNCERS estuaries as inhibiting communications between them. Mechanisms that both groups identify as useful for improving the flow of information between science and management are little used, perhaps as a result. The two groups have very different patterns of information dissemination and acquisition, and though both chose agency archives and databases as their top methods for disseminating information, neither group relies much on these vehicles for information they seek. Both residents' and practitioners' perceptions of threats to the PNCERS estuaries show patterns of estuary-to-estuary variation. One theme that emerges is that problems associated with poor land management in adjacent uplands are common to most of these estuaries, potentially providing a sense of commonality through which a more regional approach to estuary management could emerge. A common set of estuarine environmental indicators implemented for all estuaries could help instigate such a regional approach, but resource constraints, especially at the local level, will have to be overcome for that to occur. There is currently substantial lack of common vision among coastal practitioners as to the purpose and desirability of indicators, and relatively little experience or knowledge of their use, particularly at the local level. Use of estuarine science in the management of these estuaries appears to be greatest during periods in which the largest programmatic shifts in environmental management approaches occur, an observation consistent with other studies that have concluded that the use of environmental science in environmental management tends to be episodic.  相似文献   

9.
Adaptive learning about nature, based on observations and continual rethinking, dates back to Native Americans in what we call Traditional Ecological Knowledge. Fast forward to 1950+, when Eugene, Howard, and William Odum promoted sound science and its use in managing ecosystems—called adaptive management (AM). What began as an instinctive way of thinking and deciding how to obtain resources using accumulated information became a structured, science-based process that improves over time, given continual critiques of projects, clarification of definitions, and analyses of outcomes. The basic need is still to sustain ecosystem services despite uncertainties, such as climate change. I report recent innovations in the AM of estuaries and coasts that can add knowledge and improve future efforts. Innovations include new guidelines and approaches to confront uncertainty, engage stakeholders, improve governance, prioritize actions, centralize the role of science, and manage holistically. AM has been effective along the coast of Denmark and in several estuaries, and it is evolving elsewhere. In The Netherlands, Spain, California, and Oregon, large field experiments are generating “learning while restoring” (adaptive restoration, AR). AM and AR can help managers of coastal ecosystems and watersheds mitigate the impacts of rising sea levels, sea storms, and human disturbances. Science-based decision-making will become more nimble and protection/restoration more effective as innovations and model approaches are tailored to individual estuaries and coasts.  相似文献   

10.
Many types of anthropogenic stress to estuaries lead to destruction and conversion of habitats, thus altering habitat landscapes and changing the “arena” in which the life history interactions of native fauna take place. This can lead to decreased populations of valued fauna and other negative consequences. The Tampa Bay Estuary Program (TBEP) pioneered a system-wide management framework that develops estuarine habitat restoration and protection goals based on supporting estuarine-dependent species and the habitat landscapes they require (for example, the extent of seagrass beds, mangrove forests, oyster reefs, or oligohaline marshes) within an estuary. We describe this framework and provide related statistics as methods to help managers set system-wide ecological goals using larger conceptual approaches that are easily communicated to stakeholders and the public; we also discuss applications of the approach to existing and evolving paradigms of estuarine management. The TBEP and partners used this framework to combine a simple and unifying vision with a diverse and complex set of management tools, resulting in greatly improved environmental conditions within Tampa Bay.  相似文献   

11.
以典型断陷盆地——小江流域为研究对象,以1982年的TM影像、2003年的Landsat ETM+影像和2016年的Landsat OLI影像为数据源,结合云南省测绘局所提供的150 000的土地利用状况图,采用 Costanza 公式对生态系统服务价值进行评估,精细刻画出云南小江流域“盆—山”共存的地质分异结构下生态系统服务价值的时空变化特征。结果表明:(1)小江流域以农田生态系统为主,研究期内生态系统格局总体稳定,耕地、建设用地、林地和园地都有不同程度的增加,而未利用地面积减少,水域面积基本不变;(2)1982-2016年,研究区生态系统服务总价值呈上升趋势,1982、2003和2016年生态系统服务总价值分别为90.11×108元、105.65×108元和136.81×108元,耕地、林地、园地和水域的生态系统服务价值整体上升,而未利用地的生态系统服务价值减少;(3)整体上,小江流域南部和东部生态系统服务价值增加明显,而中部和西部地区生态系统服务价值呈阶段性变化或持续下降趋势,小江岩溶河谷区的生态系统服务价值最高,而沉积平坝区的生态系统服务价值密度最低,且为唯一一个衰退型生态系统服务功能区;(4)研究期内小江流域各项生态系统服务价值均呈上升趋势,调节服务居主导地位,且以气候调节服务价值最高。小江流域生态系统服务价值缺乏弹性,水域生态系统面积变化对研究区生态系统价值的变化具有放大作用。实施封山育林、退耕还林、小流域治理工程等石漠化综合治理工程可增加生态系统服务价值。   相似文献   

12.
Worldwide estuaries have been subject to multiple and escalating anthropogenic impacts which have resulted in the loss of many ecosystem goods and services including: commercial activities, navigation and marine transportation, recreational and landscape values, and flood control and biodiversity support. An example of these losses is provided in an urban-industrial region of an estuary in northern Tasmania, Australia, where excessive silt deposition has resulted in almost complete loss of the channel at low tide. The causes of siltation have long been attributed to poor watershed management and high concentrations of flocculated and suspended sediments transported upstream by asymmetrical tides. However, historical analysis of anthropogenic changes in estuarine and riverine processes revealed different stressors. These included the decrease in the tidal prism and hence regime equilibrium, brought about by channel infilling and draining of tidal wetlands to create dry land for urban and agricultural uses, and the reduction and redirection of freshwater inflows for the generation of hydroelectricity. Watershed sediment loads exerted a relatively minor role in the estuarine equilibrium, which is solely dependent on tidal flows and river discharges for maintenance of stable cross-sectional areas. Sustainable remediation measures include increasing the tidal prism through the restoration of dynamic river flows and reconnection and restoration of tidal wetlands. However, the former will not be achievable without changes in major provisioning services, particularly the use of water to generate hydroelectricity. This study emphasises the importance of identifying stressors as the basis for examining the potential to reduce the trade-offs between the multiple ecosystem services provided by an estuary and its tributaries, particularly between provisioning and cultural ecosystem services, within a rehabilitation context.  相似文献   

13.
Carbon markets have gained traction worldwide as an ostensibly win–win solution to climate change, providing low-cost emission reductions in the Global North and sustainable development in the Global South. However, sustainable development and livelihood co-benefits have largely failed to materialize in a range of carbon offset projects, particularly those in forest communities. While some scholars explain this failure as an outcome of fundamental tradeoffs between market efficiency and sustainable development, others argue that institutions of common property land tenure can resolve tradeoffs and generate important co-benefits for local communities. Using a political ecology approach, integrating insights of Karl Polanyi and Noel Castree on the commodification of nature and evidence from a carbon forestry project in Chiapas, Mexico, this article grapples with the ways in which carbon market requirements shape forest governance within common property tenure arrangements. I argue that the centralization of forest governance and decision making into the hands of project implementers and brokers, the necessity for legible land rights and boundaries, and the technical requirements for measurement, calculation, and monitoring of carbon have reshaped forest governance in ways that have undermined the social and ecological benefits often associated with common property management schemes. This research therefore demonstrates that so-called tradeoffs between market efficiency and equitable sustainable development goals may not be inherent to carbon forestry and calls into question the reliance on disembedding market mechanisms for climate change mitigation in forest ecosystems. As such, this work has important implications for REDD+.  相似文献   

14.
山水林田湖草生态保护修复技术框架研究   总被引:1,自引:0,他引:1  
面对当前严峻的资源环境与生态压力,习近平总书记提出了山水林田湖草生命共同体的理念,截至2019年底全国共开展了25个山水林田湖草生态保护修复工程试点。虽然已有工作取得了一定成效,但也存在保护修复目标不明确、整体性与系统性不足、人工干预的工程措施过度、缺乏动态监测评价、难以实现人与自然和谐共生等诸多问题。鉴此,本研究在梳理景观生态学、恢复生态学相关理论,基于自然的解决方案、适应性管理、社会-经济-自然复合生态系统以及生态系统服务等相关理念的基础上,构建了包含有区域(省)、景观、生态系统以及子项目4个层次的山水林田湖草生态保护修复技术框架,并提出了项目实施全程监测管理的技术要求,以期为推进山水林田湖草生命共同体的整体保护、系统修复、综合治理提供理论与技术支撑。  相似文献   

15.
Numerical modeling has emerged over the last several decades as a widely accepted tool for investigations in environmental sciences. In estuarine research, hydrodynamic and ecological models have moved along parallel tracks with regard to complexity, refinement, computational power, and incorporation of uncertainty. Coupled hydrodynamic-ecological models have been used to assess ecosystem processes and interactions, simulate future scenarios, and evaluate remedial actions in response to eutrophication, habitat loss, and freshwater diversion. The need to couple hydrodynamic and ecological models to address research and management questions is clear because dynamic feedbacks between biotic and physical processes are critical interactions within ecosystems. In this review, we present historical and modern perspectives on estuarine hydrodynamic and ecological modeling, consider model limitations, and address aspects of model linkage, skill assessment, and complexity. We discuss the balance between spatial and temporal resolution and present examples using different spatiotemporal scales. Finally, we recommend future lines of inquiry, approaches to balance complexity and uncertainty, and model transparency and utility. It is idealistic to think we can pursue a “theory of everything” for estuarine models, but recent advances suggest that models for both scientific investigations and management applications will continue to improve in terms of realism, precision, and accuracy.  相似文献   

16.
The demand for ecosystem services and the ability of natural ecosystems to provide those services evolve over time as population, land use, and management practices change. Regionalization of ecosystem service activity, or the expansion of the area providing ecosystem services to a population, is a common response in densely populated coastal regions, with important consequences for watershed water and nitrogen (N) fluxes to the coastal zone. We link biophysical and historical information to explore the causes and consequences of change in ecosystem service activity—focusing on water provisioning and N regulation—from 1850 to 2010 in a coastal suburban watershed, the Ipswich River watershed in northeastern Massachusetts, USA. Net interbasin water transfers started in the late 1800s due to regionalization of water supply for use by larger populations living outside the Ipswich watershed boundaries, reaching a peak in the mid-1980s. Over much of the twentieth century, about 20 % of river runoff was diverted from reaching the estuary, with greater proportions during drought years. Ongoing regionalization of water supply has contributed to recent declines in diversions, influenced by socioecological feedbacks resulting from the river drying and fish kills. Similarly, the N budget has been greatly perturbed since the suburban era began in the 1950s due to food and lawn fertilizer imports and human waste release. However, natural ecosystems are able to remove most of this anthropogenic N, mitigating impacts on the coastal zone. We propose a conceptual model whereby the amount and type of ecosystem services provided by coastal watersheds in urban regions expand and contract over time as regional population expands and ecosystem services are regionalized. We hypothesize that suburban watersheds can be hotspots of ecosystem service sources because they retain sufficient ecosystem function to still produce services that meet increasing demand from the local population and nearby urban centers. Historical reconstruction of ecosystem service activity provides a perspective that may help to better understand coupled human–natural system processes and lead to more sustainable management of coastal ecosystems.  相似文献   

17.
Policy makers and scientists consider that land use strategies are designed to provide direct benefits to people by protecting vital ecosystem services. However, due to lack of information and evaluation methods, there is no effective and systematic tool for assessing tradeoffs between direct human benefits and ecosystem services. Land use changes influence ecosystem properties, processes and components, which are the basis for providing services. Five alternative land use scenarios (no conversion of agricultural lands, no urban expansion, agricultural expansion, forestry expansion, and riparian reforestation) were modeled for the Baiyangdian watershed, China, a densely populated, highly modified watershed with serious water shortage and pollution problems. The model InVEST (Integrated Valuation of Ecosystem Services and Tradeoffs) is designed to inform decisions about natural resource management, with an aim to align economic forces with conservation. Three ecosystem services (agricultural production, hydropower production, and water quality) were modeled to balance direct benefits and hydrological ecosystem services using InVEST. The results showed that: hydropower production was the greatest in the forestry expansion, but the lowest in agricultural expansion; agricultural production was reduced the most in forestry expansion, while retained the most in riparian reforestation. Riparian reforestation also provided the highest N and P retention and lowest N and P exportation. Riparian reforestation was the optimal land use strategy, since it protected and enhanced the vital ecosystem services without undermining direct human benefits. This research presents an initial analytical framework for integrating direct human benefits and ecosystem services in policy planning and illustrates its application. Although there are important potential tradeoffs between ecosystem services, this systematic planning framework offers a means for identifying valuable synergies between conservation and development.  相似文献   

18.
As the largest ecosystems of the earth, marine ecosystem provides many types of ecosystem service to human. More than 60% of the global population lives the coastal area. A healthy ocean is critical to our economy, health and way of life. However, with rapid population growth and densely inhabited coastal areas, our dependence on marine resources is greater than ever. The overuse and mismanagement of ecosystem services have placed great pressure on marine systems, thereby threatening the future of marine ecosystems, and the services they provide. With anthropogenic pressures increasing in coastal cities, adopting ecosystem-based management frameworks that minimize impacts on marine environments while allowing for sustainable development is critical. Marine Ecosystem-Based Management seeks to manage marine resources in ways that protect ecosystem health while providing the ecosystem services needed by people. Rather than focusing solely on a single species or resource, MEBM incorporates science and balances the demands of user groups in a manner that produces management strategies that are more likely to be sustainable than traditional approaches. The definition, principles and framework were discussed in this paper based on the summary of literature, and two examples were introduced. Last, some suggestions were put forward to marine ecosystem management for ocean ecosystem and for healthy coastal resources sustainable utilization.  相似文献   

19.
生态系统与人类健康   总被引:1,自引:0,他引:1  
简要介绍了千年生态系统评估(MA)项目针对生态系统与人类健康编写的《生态系统与人类福祉:健康综合报告》的核心内容。报告表明:① 生态系统及其服务是人类生存和维持健康的根基,但生态系统与人类健康之间的关系多是间接性的,可能出现时空移位,而且还会受到许多动态因素的影响,因而对其认知难度较大;② 在过去的50年中,主要由人类活动造成的生态系统变化,一方面显著改善了人类的健康状况,另一方面人类也为此付出了日益昂贵的代价,并对未来的人类健康构成了新的威胁;③ 对于未来50年(2000—2050年)的生态系统变化与人类健康状况,虽然MA的4种情景的模拟结果不尽相同,但是,它们一致认为人类对食物和水资源等生态系统服务的需求将大幅增长,人类活动对生态系统的快速转化将会持续,而且难以实现食物安全及消除儿童营养不良等目标;④ 长远来看,生态系统的可持续管理与人类健康状况的改善具有相互促进作用。但是,为了实现改善人类健康和保育生态系统的双赢目标,必需对现行的管理、制度、法规和政策等进行一系列的全面改革。  相似文献   

20.
Living resources in estuarine systems have been so intensively harvested that many fisheries are severely depleted at a time when demand for these resources is rising. In addition, multiple use demands on estuaries often conflict, leaving unresolved management questions. With the movement of the population to the coastal regions, conflicts among uses and users of estuarine resources are increasing. Aquaculture offers one means to reconcile the conflicting demands for use of the estuarine resource. Yet, the nation has few, if any new policy or management approaches to address these conflicts. Management on the level of the watershed is one effective tool that should be more effectively used. Involvement of the full range of stakeholders or user groups in policy setting and management options has brought remarkable success in a small number of cases where this approach has been used. The nation will need to develop other tools and approaches if estuaries are to be restored and protected as protected as planned in federal, regional, and state laws and initiatives.  相似文献   

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