842 resultados para ECOSYSTEM SERVICES
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时空尺度和生态系统的健康状况是影响生态系统服务功能的重要因素。锡林河流域天然草地关键的地理位置和独特的生境条件使其具有十分重要的生态意义和经济价值。评估锡林河流域天然草地在不同时空尺度及生态系统健康状况的生态系统服务功能的价值,不仅能够全面客观的评价该流域天然草地的生态服务功能,而且还能够为当地经济政策的制定,经济的建设发展提供科学依据。 本研究以锡林河流域天然草地为例,通过对草地生态系统服务功能价值评估和计算机情景模拟,研究了不同空间尺度及放牧影响锡林河流域天然草地生态系统服务功能价值。对于不同空间尺度下草地生态系统服务价值的研究,根据草地的产草量和退化程度将锡林河流域天然草地划分成5个级别,利用Costanza等的基本思路和方法,进行了价值评估。结果表明锡林河流域草地生态系统每年的服务价值为76.154×108元。受各级草场的生产量和放牧强度的综合影响,健康程度不同的各等级天然草地的单位面积生态系统服务功能的价值存在着很大差异,从1级草地到5级草地,单位面积服务价值比重从38.1%下降到4.8%。参考国际、国内和锡林浩特当地三种不同的生态系统服务单价,计算得出这三种不同空间尺度下锡林河流域天然草场生态系统服务价值分别为:88.199×108元/年、76.154×108元/年、14.236×108元/年,并且各项服务功能在总价值中所占的比例也随空间尺度变化。以气体调节为例,服务价值的比重分别占3.7%、11.0%和7.9%,这说明生态系统服务功能的价值与空间尺度有关。 通过草地生态系统服务功能当量因子得到不同类型草地生态系统单位面积服务价值,研究放牧影响下各类型草地生态系统单位面积服务价值以及年平均累积服务价值。草地生态系统服务功能当量因子说明生态系统各项服务功能不仅与生态系统的生物量有关,同时受到生态系统内环境因子、生物因子、生态系统过程多方面因素的共同作用。最大直接经济价值放牧率大于生态系统服务功能最大时的放牧率,但是获得经济利润小于生态系统服务功能最大时的价值。同时,在各类草地生态系统中单位面积服务价值以贝加尔针茅草原最高为2242.347元/公顷,克氏针茅草原最低为1655.413元/公顷。草地生态系统的累积服务价值在时间范围一定时随放牧率变化明显,并且时间范围越大变化越大。重牧状态下的草地生态系统累积服务价值最低,且随时间的增加而减少;无牧、轻牧和中牧状态下草地生态系统的累积服务价值则随时间的延续而增长。以上结果说明放牧对草地生态系统服务功能有显著影响,以经济利益为目的获得最大利润的放牧方式带来的经济价值是短期的,从长远看,只有科学管理,合理放牧,才能使草地生态系统长期稳定的提供最佳的生态系统服务功能。
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草地退化不仅仅是今天中国才发生的事情。历史上曾经发生“黑尘暴”的美国North Dakota州,现在仍然有62.7%土地被用作耕作,林地所占面积仅仅占1%。私有制和种植业较畜牧业的高的利润率,是该州种植业比重高于畜牧业的重要原因。草原保护项目(CRP)得到了美国政府财政的大力支持, 在North Dakota州采用了以草地恢复为主的措施。美国发达的教育体系带来的高流动率,使得North Dakota州自30年代后居住人口稳定在60-70万成为可能,从而避免了我国出现的草原地区不断增加的人口压力。由此可见:草地作为重要的自然资源,不可能完全保护起来;没有其他配套措施,私有制可能会带来新一轮垦殖;草地畜牧业仍然是畜牧业的重要组成部分,畜牧业发展需要结合种植业尤其需要与饲料生产相结合。 依据生态系统服务的理念,首次发展了生态系统服务指数(ESI),试图通过对生态系统服务功能的综合考虑,提出科学的适宜放牧率的评价方法。本文利用美国北达科他州立大学中部草原研究站17年长期放牧试验数据,选取植物多样性Shannon-Wiener指数、地上净初级生产力、土壤表层含水量和单位面积家畜增重等四个指标,通过对不同指标分别赋予不同的权重,计算不同管理目标下ESI及其稳定性,并对单目标管理与多目标管理进行了比较研究。结果表明,对于北美混合普列里(Prairie)草地,围封不利用或建立自然保护区,虽然生态系统比较稳定,但既不能有效的提高植物多样性、初级生产力和土壤水分含量等生态功能,又没有畜产品产出;而在重牧或极重牧处理下虽然获得了较大的畜产品生产,但导致了草地生态系统的退化和较大的系统不稳定性。因此,这两种管理方式在实践中都是不可取的。应用生态系统服务指数综合考虑,认为应该权衡各项生态功能和生产功能,此时轻牧或中牧是最适宜的。因此,ESI的建立避免了单项指标的评价偏差,使得适宜放牧率的确定更加合理。 利用前面构建的多目标权重评价体系,结合内蒙古草原生态系统定位站放牧试验样地的数据,探讨了锡林郭勒盟定位站附近的适宜放牧率为2.67羊/ha,低于单目标条件下的每公顷绵羊4羊/ha。同时在经济学和生态系统系统服务理论的基础上,依据谢高地等人(2001年)的研究,并提出了环境税和生态补偿的标准,分别是每公顷15元和90元。
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生态补偿机制因为能有效解决环境保护领域的外部性问题而日益引起关注。它是一套对造成自然环境破坏的行为进行处罚、对生态环境保护的行为实行奖励的制度。生态补偿机制不但能为生态保护筹措资金,而且能统筹协调各区域和各行业的关系,从而达到经济发展与保护生态平衡协调、区域协调发展和可持续发展的最终目标。 首先进行了生态补偿的理论研究。分析了生态补偿的概念、经济学原理、生态补偿网络的构成、以及目前在确定生态补偿的补偿依据和补偿额度方面所面临的问题和争议。引进生态系统服务功能评价的原理与方法,探讨将生态系统服务功能评价应用于生态补偿的可行性,并提出了生态补偿的组成部分和一般机制。 区域补偿是一类重要的生态补类型。山东省是一个面积较大、经济较发达、但各地发展还不够平衡的省份,在山东开展生态补偿具有重要意义。以山东省为研究案例,研究了在山东省开展区域生态补偿的可行性和实施办法,并根据山东省各地的生态系统服务功能提出优先补偿地区。提出了综合考虑各区域的单位面积非市场生态系统服务功能价值和单位面积GDP的生态补偿决策因子,并对山东不同生态功能区和17市的生态补偿决策因子分别进行了计算。从研究的结果来看,山东西部地区由于经济较落后和生态系统服务功能中的非市场价值较大而拥有相对较大的生态补偿决策因子,应该优先给与区域生态补偿,以促进山东整个区域的协调发展。 生态系统类型转换的补偿是生态补偿的重要组成部分。在山东省南四湖地区开展退耕还湿生态工程对保障南水北调东线工程水质安全具有重要意义,但要在当地开展大规模退耕还湿,合理的生态补偿机制至关重要。以南四湖地区退耕还湿地生态工程的生态效益和生态补偿机制为研究案例,探讨了生态系统类型转换的生态补偿方法。研究发现南四湖退耕还湿后生态系统服务功能大为增强,但当地农民的收入会受到显著负面影响,因此应该给与一定的资金补偿以提高农民参与退耕还湿的积极性和促进整个区域的可持续发展。另外,生态补偿的方式应该多样化和结合当地实际,除资金补偿以外,南四湖地区还应该重点采取技术补偿的方式,由政府组织专家给当地居民提供湿地恢复和湿地植物资源开发的技术。资金补偿和技术补偿对以提高农民退耕还湿的积极性和湿地系统的长期稳定运行具有重要意义。 最后对生态补偿的实施和保障机制进行了理论探讨。结合山东的研究案例和参考国内外经验,讨论和提出了生态补偿的主管部门、补偿费用征收机制、补偿费用使用的机制、生态补偿费用使用的监督机制等,并对生态补偿机制存在的问题进行了分析。根据研究结果对山东实施生态补偿的优先领域进行了讨论并提出了建议。 总之,通过生态补偿机制的理论研究和在山东开展生态补偿的案例研究,提出了生态补偿的一般机制和保障措施,以及对山东省开展生态补偿的建议,研究结果对促进生态补偿和可持续发展具有重要意义。
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There is increasing awareness that integrating gender into development frameworks is critical for effective implementation of development strategies. In working to alleviate rural poverty, the CGIAR Research Program on Aquatic Agricultural Systems (AAS) recognizes that “business as usual” gender integration approaches will not deliver lasting and widespread improvements in agricultural productivity, poverty reduction and food security. In response, AAS operationalized a gender transformative approach. The approach is informed by conceptual frameworks that explicitly recognize the potent influence of social relations on creating and perpetuating gender inequalities. In this way, AAS aims to address the underlying causes of rural poverty and gender inequality in Zambia’s Barotse Floodplain, where people rely extensively on riverine and wetland ecosystems for food and livelihood security. A central question guiding the research program is “How do social norms and gendered power relations influence agricultural development outcomes?” The findings presented in this report provide insights that help answer this question. The report presents a review of literature relevant to livelihoods, ecosystem services, and gender and social relations in Zambia, with a specific focus on Western Province, where AAS is currently implemented. It also presents a synthesis of findings of a social and gender analysis conducted in 2013 in 10 focal communities situated in and around the Barotse Floodplain.
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生态系统服务评价可清晰地揭示生态环境问题产生的经济根源。由于生态系统服务的复杂性、多样性、重叠性,需选择合适的研究尺度及方法才可使评价结果进入管理、决策过程。 本文以本溪县森林生态系统服务评价为例,确定适合县域尺度的评价方法,借助GIS技术,揭示森林生态系统提供林木生产、水源涵养、土壤保持、气体调节等四种服务的物质量、价值量及其空间分布规律。不同生态系统服务空间分布规律的研究对于维护和提高区域森林生态系统提供生态系统服务能力具有重要意义。主要研究结果如下: (1)研究区森林面积2.72×105ha,以天然次生林为主,中、幼龄林比重较大,森林郁闭度大。按优势树种可划分为蒙古栎、落叶松、色木、胡桃楸、红松、油松、千金榆、枫桦和杂木林等九种类型。 (2)研究区森林生态系统活立木生长量为2.56 m³•ha-1•a-1,森林水源涵养量为873m³•ha-2,土壤保持量为6.77 t•ha-1•a-1,固定CO2为5.15t•ha-1•a-1;活立木生产价值为200元•ha-1•a-1,水源涵养价值为611元•ha-1,土壤保持经济价值为663元•ha-1•a-1,固定CO2为6411元•ha-1•a-1;研究区总活立木生产价值为5.43×107元•a-1,水源涵养价值为1.66×108元,土壤保持价值为1.80×108元•a-1, CO2年固定价值1.74×109元•a-1。 (3)生态系统服务价值较高的区域在研究区中部偏南、偏北集中分布,在南部、东南部零星分布。
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21世纪,中国的人口和经济的持续增长面临着资源短缺和生态脆弱的限制。提高资源利用效率和消减资源利用引起的环境影响是学术界和决策者面临的新课题。本文从资源流动的视角研究资源利用过程及其引起的环境影响。我们把资源流动过程分解为开采、加工、转化、消费等几个关键环节,评价其资源利用效率和环境影响,并寻求改善的途径。因其资源消耗量大、生态环境影响严重,我们选取了林木、煤炭及石油研究其资源与产品流动及其环境影响。林木产品的产量、进出口量和消费量数据来自中国森林统计年鉴(1949-2001)。煤炭、石油的开采量、进出口
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Science & Technology Basic Work Program of China: Scientific Survey of the Middle-lower Reaches of Lantsang River and the Great Shangri-La Region [2008FY110300]; National Basic Research Program of China (973 Program): Ecosystem Services and Ecological Safety of the Major Terrestrial Ecosystems of China [2009CB421106]; National Natural Science Foundation of China [30670374]; EU ; European Commission, DG Research [003874]
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The interactions among industrial development, land use/cover change (LUCC), and environmental effects in Changshu in the eastern coastal China were analyzed using high-resolution Landsat TM data in 1990, 1995, 2000, and 2006, socio-economic data and water environmental quality monitoring data from research institutes and governmental departments. Three phases of industrial development in Changshu were examined (i.e., the three periods of 1990 to 1995, 1995 to 2000, and 2000 to 2006). Besides industrial development and rapid urbanization, land use/cover in Changshu had changed drastically from 1990 to 2006. This change was characterized by major replacements of farmland by urban and rural settlements, artificial ponds, forested and constructed land. Industrialization, urbanization, agricultural structure adjustment, and rural housing construction were the major socio-economic driving forces of LUCC in Changshu. In addition, the annual value of ecosystem services in Changshu decreased slightly during 1990-2000, but increased significantly during 2000-2006. Nevertheless, the local environmental quality in Changshu, especially in rural areas, has not yet been improved significantly. Thus, this paper suggests an increased attention to fully realize the role of land supply in adjustment of environment-friendly industrial structure and urban-rural spatial restructuring, and translating the land management and environmental protection policies into an optimized industrial distribution and land-use pattern.
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Experimental studies of how global changes and human activities affect plant diversity often focus on broad measures of diversity and discuss the implications of these changes for ecosystem function. We examined how experimental warming and grazing affected species within plant groups of direct importance to Tibetan pastoralists: medicinal plants used by humans and palatable plants consumed by livestock. Warming resulted in species losses from both the medicinal and palatable plant groups; however, differential relative vulnerability to warming occurred. With respect to the percent of warming-induced species losses, the overall plant community lost 27%, medicinal plants lost 21%, and non-medicinal plants lost 40% of species. Losses of palatable and non-palatable species were similar to losses in the overall plant community. The deep-rootedness of medicinal plants resulted in lowered sensitivity to warming, whereas the shallow-rootedness of non-medicinal plants resulted in greater sensitivity to warming; the variable rooting depth of palatable and non-palatable plants resulted in an intermediate response to warming. Predicting the vulnerability of plant groups to human activities can be enhanced by knowledge of plant traits, their response to specific drivers, and their distribution within plant groups. Knowledge of the mechanisms through which a driver operates, and the evolutionary interaction of plants with that driver, will aid predictions. Future steps to protect ecosystem services furnished by medicinal and palatable plants will be required under the novel stress of a warmer climate. Grazing may be an important tool in maintaining some of these services under future warming.
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This paper outlines what we have learned about the impacts of the Deepwater Horizon (DWH) oil disaster from the economics discipline as well as what effect the DWH disaster has had on the economics discipline. It appears that what we know about the economic impact of the DWH spill today is limited, possibly because such analysis is tied up in the federal Natural Resource Damage Assessment (NRDA) process and other state-led efforts. There is evidence, however, that the NRDA process has changed over time to de-emphasize economic valuation of damages. There is also evidence that economists may be producing fewer outputs as a result of the DWH relative to scholars from other disciplines because of an apparent absence of funding for it. Of the research that has taken place, this paper provides a summary and highlights the main directions of future research. It appears that the most pressing topic is addressing the incentives and policies in place to promote a culture of safety in the offshore oil industry. Also, it appears that the most prominent, and challenging, direction of future research resulting from the DWH is the expansion of an ecosystems services approach to damage assessment and marine policy. Lea el abstracto en español 请点击此处阅读中文摘要
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A model to estimate the mean monthly growth of Crassostrea virginica oysters in Chesapeake Bay was developed. This model is based on the classic von Bertalanffy growth function, however the growth constant is changed every monthly timestep in response to short term changes in temperature and salinity. Using a dynamically varying growth constant allows the model to capture seasonal oscillations in growth, and growth responses to changing environmental conditions that previous applications of the von Bertalanffy model do not capture. This model is further expanded to include an estimation of Perkinsus marinus impacts on growth rates as well as estimations of ecosystem services provided by a restored oyster bar over time. The model was validated by comparing growth estimates from the model to oyster shell height observations from a variety of restoration sites in the upper Chesapeake Bay. Without using the P. marinus impact on growth, the model consistently overestimates mean oyster growth. However, when P. marinus effects are included in the model, the model estimates match the observed mean shell height closely for at least the first 3 years of growth. The estimates of ecosystem services suggested by this model imply that even with high levels of mortality on an oyster reef, the ecosystem services provided by that reef can still be maintained by growth for several years. Because larger oyster filter more water than smaller ones, larger oysters contribute more to the filtration and nutrient removal ecosystem services of the reef. Therefore a reef with an abundance of larger oysters will provide better filtration and nutrient removal. This implies that if an oyster restoration project is trying to improve water quality through oyster filtration, it is important to maintain the larger older oysters on the reef.
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Marine protected areas (MPAs) are often implemented to conserve or restore species, fisheries, habitats, ecosystems, and ecological functions and services; buffer against the ecological effects of climate change; and alleviate poverty in coastal communities. Scientific research provides valuable insights into the social and ecological impacts of MPAs, as well as the factors that shape these impacts, providing useful guidance or "rules of thumb" for science-based MPA policy. Both ecological and social factors foster effective MPAs, including substantial coverage of representative habitats and oceanographic conditions; diverse size and spacing; protection of habitat bottlenecks; participatory decisionmaking arrangements; bounded and contextually appropriate resource use rights; active and accountable monitoring and enforcement systems; and accessible conflict resolution mechanisms. For MPAs to realize their full potential as a tool for ocean governance, further advances in policy-relevant MPA science are required. These research frontiers include MPA impacts on nontarget and wide-ranging species and habitats; impacts beyond MPA boundaries, on ecosystem services, and on resource-dependent human populations, as well as potential scale mismatches of ecosystem service flows. Explicitly treating MPAs as "policy experiments" and employing the tools of impact evaluation holds particular promise as a way for policy-relevant science to inform and advance science-based MPA policy. © 2011 Wiley Periodicals, Inc.
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Restoration has been elevated as an important strategy to reverse the decline of coastal wetlands worldwide. Current practice in restoration science emphasizes minimizing competition between outplanted propagules to maximize planting success. This paradigm persists despite the fact that foundational theory in ecology demonstrates that positive species interactions are key to organism success under high physical stress, such as recolonization of bare substrate. As evidence of how entrenched this restoration paradigm is, our survey of 25 restoration organizations in 14 states in the United States revealed that >95% of these agencies assume minimizing negative interactions (i.e., competition) between outplants will maximize propagule growth. Restoration experiments in both Western and Eastern Atlantic salt marshes demonstrate, however, that a simple change in planting configuration (placing propagules next to, rather than at a distance from, each other) results in harnessing facilitation and increased yields by 107% on average. Thus, small adjustments in restoration design may catalyze untapped positive species interactions, resulting in significantly higher restoration success with no added cost. As positive interactions between organisms commonly occur in coastal ecosystems (especially in more physically stressful areas like uncolonized substrate) and conservation resources are limited, transformation of the coastal restoration paradigm to incorporate facilitation theory may enhance conservation efforts, shoreline defense, and provisioning of ecosystem services such as fisheries production.
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The effect of elevated pCO(2)/low pH on marine invertebrate benthic biodiversity, community structure and selected functional responses which underpin ecosystem services (such as community production and calcification) was tested in a medium-term (30 days) mesocosm experiment in June 2010. Standardised intertidal macrobenthic communities, collected (50.3567A degrees N, 4.1277A degrees W) using artificial substrate units (ASUs), were exposed to one of seven pH treatments (8.05, 7.8. 7.6, 7.4, 7.2, 6.8 and 6.0). Community net calcification/dissolution rates, as well as changes in biomass, community structure and diversity, were measured at the end of the experimental period. Communities showed significant changes in structure and reduced diversity in response to reduced pH: shifting from a community dominated by calcareous organisms to one dominated by non-calcareous organisms around either pH 7.2 (number of individuals and species) or pH 7.8 (biomass). These results were supported by a reduced total weight of CaCO3 structures in all major taxa at lowered pH and a switch from net calcification to net dissolution around pH 7.4 (a"broken vertical bar(calc) = 0.78, a"broken vertical bar(ara) = 0.5). Overall community soft tissue biomass did not change with pH and high mortality was observed only at pH 6.0, although molluscs and arthropods showed significant decreases in soft tissue. This study supports and refines previous findings on how elevated pCO(2) can induce changes in marine biodiversity, underlined by differential vulnerability of different phyla. In addition, it shows significant elevated pCO(2)-/low pH-dependent changes in fundamental community functional responses underpinning changes in ecosystem services.
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Sustainable development depends on maintaining ecosystem services which are concentrated in coastal marine and estuarine ecosystems. Analyses of the science needed to manage human uses of ecosystem services have concentrated on terrestrial ecosystems. Our focus is on the provision of multidisciplinary data needed to inform adaptive, ecosystem-based approaches (EBAs) for maintaining coastal ecosystem services based on comparative ecosystem analyses. Key indicators of pressures on coastal ecosystems, ecosystem states and the impacts of changes in states on services are identified for monitoring and analysis at a global coastal network of sentinel sites nested in the ocean-climate observing system. Biodiversity is targeted as the “master” indicator because of its importance to a broad spectrum of services. Ultimately, successful implementation of EBAs will depend on establishing integrated, holistic approaches to ocean governance that oversee the development of integrated, operational ocean observing systems based on the data and information requirements specified by a broad spectrum of stakeholders for sustainable development. Sustained engagement of such a spectrum of stakeholders on a global scale is not feasible. The global coastal network will need to be customized locally and regionally based on priorities established by stakeholders in their respective regions. The E.U. Marine Strategy Framework Directive and the U.S. Recommendations of the Interagency Ocean Policy Task Force are important examples of emerging regional scale approaches. The effectiveness of these policies will depend on the co-evolution of ocean policy and the observing system under the auspices of integrated ocean governance.