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1.
张掖黑河湿地自然保护区生态服务功能价值评估   总被引:6,自引:9,他引:6  
孔东升  张灏 《生态学报》2015,35(4):972-983
张掖黑河湿地国家级自然保护区地处内陆干旱区,是西北典型的内陆河流湿地生态系统,具有多种重要的生态服务功能。通过野外调查和实验室分析,借助市场价值法、碳税法、影子工程法、生态价值法、旅行费用法等生态服务功能评估方法,对研究区湿地的各项生态功能进行了价值估算。结果表明,黑河湿地自然保护区生态服务功能总价值约为32.89×108元,其中各生态服务功能的价值量依次为:调蓄洪水功能湿地固碳释氧功能旅游休闲功能提供水源功能气候调节功能物质生产功能生物栖息地功能科研教育价值功能降解污染物功能。直观的货币价值突显了保护区湿地对区域经济发展的重要性,同时也为我国湿地生态系统的保护和管理提供科学的理论依据。  相似文献   

2.
The biological and ecological integrity of marine ecosystems in the Pearl River Estuary (PRE) has been compromised due to overfishing and water pollution. Fishing moratorium and artificial reef construction have been implemented in Wanshan and Miaowan for resource protection and restoration. Therefore, food web structure and trophic pathways of Wanshan, Miaowan, and Wailingding in different temporal and spatial situation will be determined using the Ecopath model, as well as the keystone species affecting these ecosystems, which can provide a basis for fishery management. The results showed that the energy transfer efficiency of IV and V trophic levels (TL) was higher than that of II and III‐TL before and after fishing moratorium, and the energy transfer efficiency of artificial reefs II and III‐TL was only slightly higher than that of nonartificial reefs in Wanshan. In addition, the mean values of ecosystem property indicators (consumption, respiration flow, total system throughput, and total biomass) after the fishing moratorium were significantly higher than those before the fishing moratorium. The average value of the ecosystem attribute indicators (consumption, respiration flow, total system throughput, and total biomass) of artificial reefs is lower than those of nonartificial reef areas, which may be related to the differences in community composition between artificial reefs and non‐artificial reefs. Finally, Nemipterus japonicus and Gastrophysus spadiceus are keystone species that distinguish the Wanshan and Miaowan artificial reefs from other areas. Overall, the fishing moratorium has a positive effect on the short‐term restoration of fishery resources, mainly restoring short‐life cycle organisms. However, the construction of artificial reefs will be more conducive to the persistence of ecosystem restoration. In addition, reasonable proliferation, release and fishing of N. japonicus and G. spadiceus will be beneficial to the sustainable utilization of fishery resources.  相似文献   

3.
Whole‐body morphometrics and 15 nuclear DNA microsatellite loci were analysed for 158 Perca flavescens collected during the spawning season from four spawning locations in central Lake Erie, two along the northern shore and two along the southern shore, to evaluate fine‐scale variation (spanning 17–94 km). Results showed significant morphological and genetic differences among P. flavescens from the four locations. The magnitudes of differences were unrelated to geographic distance, demonstrating spatially heterogeneous levels of genetic divergence. These results linked morphometric and genetic variation, showing a discontinuity of scale between currently defined management units and population structure of P. flavescens in Lake Erie, and support that P. flavescens might exist as one or more metapopulations. Findings demonstrate the value of using complementary techniques for evaluating population structure.  相似文献   

4.
Dramatic coral loss has significantly altered many Caribbean reefs, with potentially important consequences for the ecological functions and ecosystem services provided by reef systems. Many studies examine coral loss and its causes—and often presume a universal decline of ecosystem services with coral loss—rather than evaluating the range of possible outcomes for a diversity of ecosystem functions and services at reefs varying in coral cover. We evaluate 10 key ecosystem metrics, relating to a variety of different reef ecosystem functions and services, on 328 Caribbean reefs varying in coral cover. We focus on the range and variability of these metrics rather than on mean responses. In contrast to a prevailing paradigm, we document high variability for a variety of metrics, and for many the range of outcomes is not related to coral cover. We find numerous “bright spots,” where herbivorous fish biomass, density of large fishes, fishery value, and/or fish species richness are high, despite low coral cover. Although it remains critical to protect and restore corals, understanding variability in ecosystem metrics among low‐coral reefs can facilitate the maintenance of reefs with sustained functions and services as we work to restore degraded systems. This framework can be applied to other ecosystems in the Anthropocene to better understand variance in ecosystem service outcomes and identify where and why bright spots exist.  相似文献   

5.
Recent evidence strongly suggests that biodiversity loss and ecosystem degradation continue. How might a systems approach to ecology help us better understand and address these issues? Systems approaches play a very limited role in the science that underpins traditional biodiversity conservation, but could provide important insights into mechanisms that affect population growth. This potential is illustrated using data from a critically endangered bird population. Although species-specific insights have practical value, the main applied challenge for a systems approach is to help improve our understanding of the role of biodiversity in the context of ecosystem services (ES) and the associated values and benefits people derive from these services. This has profound implications for the way we conceptualize and address ecological problems. Instead of focusing directly on biodiversity, the important response variables become measures of values and benefits, ES or ecosystem processes. We then need to understand the sensitivity of these variables to biodiversity change relative to other abiotic or anthropogenic factors, which includes exploring the role of variability at different levels of biological organization. These issues are discussed using the recent UK National Ecosystems Assessment as a framework.  相似文献   

6.
Valley‐bottom wetlands are valuable assets as they provide many ecosystem services to mankind. Despite their value, valley‐bottom wetlands are often exploited and land‐use/land‐cover (LULC) change results in trade‐offs in ecosystem services. We coupled physically based hydrological modeling and spatial analysis to examine the effects of LULC change on water‐related ecosystem services in the Kromme catchment: an important water‐providing catchment for the city of Port Elizabeth. LULC scenarios were constructed to match 5 different decades in the last 50 years to explore the potential effects of restoring the catchment to different historic benchmarks. In the Kromme catchment, valley‐bottom wetlands have declined by 84%, driven by key LULC changes: an increase in irrigated land (307 ha) and invasion by alien trees (336 ha). If the wetlands were restored to the relatively pristine extent and condition of the 1950s, riverflow could increase by approximately 1.13 million m3/a, about 6% of the current supply to Port Elizabeth. Wetland restoration would also significantly improve the catchment's ability to absorb extreme rainfall events, decreasing flood damage. We conclude that in the face of the water scarcity in this region, all ecosystem services, particularly those related to water flow regulation, should be taken into account by decision makers in charge of land zonation. Zonation decisions should not continue to be made on the basis of provisioning ecosystem services alone (i.e. food provision or dam yield). We recommend prioritization of the preservation and restoration of valley‐bottom wetlands providing water‐related ecosystem services to settlements downstream.  相似文献   

7.
This paper considers traditional resources and fire management practices of Aboriginal people living in a near-coastal region of western Arnhem Land, monsoonal northern Australia. The data illustrate that before the arrival of Europeans freshwater floodplains and riverine habitats provided the major proportion of food resources over much of the seasonal cycle. By contrast, the extensive lowland woodlands and open forests, the sparser vegetation of the Arnhem Land escarpment and plateau, and the generally small patches of rain forest (jungle), provided relatively few resources, although jungle yams were of critical importance through the relatively lean wet season. The paper then considers burning as a management tool through the seasonal cycle. In broad terms, burning commenced in the early dry season and was applied systematically and purposefully over the landscape. Burning in the late dry season was undertaken with care, and resumed in earnest with the onset of the first storms of the new wet season, particularly on floodplains. These general patterns of resource use and fire management are shown to have applied widely over much of near-coastal northern Australia. The implications of these data for prehistory and for contemporary land management practices in the region, are considered. It is suggested that pre-European patterns of fire management in the region are likely to have been practiced only over the past few thousand years, given the development of abundant food resources in the late Holocene. It is shown that traditional burning practice offers a generally useful, conservative model for living in and managing a highly fire-prone savanna environment.  相似文献   

8.
This review addresses the main issues concerning anticipated demands for the use of land for food and for bioenergy. It should be possible to meet increasing demands for food using existing and new technologies although this may not be easily or cheaply accomplished. The alleviation of hunger depends on food accessibility as well as food availability. Modern civilizations also require energy. This article presents the vision for bioenergy in terms of four major gains for society: a reduction in C emissions from the substitution of fossil fuels with appropriate energy crops; a significant contribution to energy security by reductions in fossil fuel dependence, for example, to meet government targets; new options that stimulate rural and urban economic development, and reduced dependence of global agriculture on fossil fuels. This vision is likely to be best fulfilled by the use of dedicated perennial bioenergy crops. We outline a number of factors that need to be taken into account in estimating the land area available for bioenergy. In terms of provisioning services, the value of biofuels is estimated at $54.7?$330 bn per year at a crude oil price of $100 per barrel. In terms of regulatory services, the value of carbon emissions saved is estimated at $56?$218 bn at a carbon price of $40 per tonne. Although global government subsidies for biofuels have been estimated at $20 bn (IEA, 2010b), these are dwarfed by subsidies for fossil fuel consumption ($312 bn; IEA, 2010b) and by total agricultural support for food and commodity crops ($383.7 bn in 2009; OECD, 2010).  相似文献   

9.
Terra Preta soils of central Amazonia exhibit approximately three times more soil organic matter, nitrogen and phosphorus and 70 times more charcoal compared to adjacent infertile soils. The Terra Preta soils were generated by pre-Columbian native populations by chance or intentionally adding large amounts of charred residues (charcoal), organic wastes, excrements and bones. In this paper, it is argued that generating new Terra Preta sites ('Terra Preta nova') could be the basis for sustainable agriculture in the twenty-first century to produce food for billions of people, and could lead to attaining three Millennium Development Goals: (i) to combat desertification, (ii) to sequester atmospheric CO2 in the long term, and (iii) to maintain biodiversity hotspots such as tropical rainforests. Therefore, large-scale generation and utilization of Terra Preta soils would decrease the pressure on primary forests that are being extensively cleared for agricultural use with only limited fertility and sustainability and, hence, only providing a limited time for cropping. This would maintain biodiversity while mitigating both land degradation and climate change. However, it should not be overlooked that the infertility of most tropical soils (and associated low population density) is what could have prevented tropical forests undergoing large-scale clearance for agriculture. Increased fertility may increase the populations supported by shifting cultivation, thereby maintaining and increasing pressure on forests.  相似文献   

10.
杨海乐  危起伟  陈家宽 《生态学报》2020,40(10):3218-3228
选择容量价值是指,一项人类生存生产所必需的生态系统服务,其总量为消费该生态系统服务的消费活动所提供的选择自由度(即选择容量,optional capacity)与该消费活动所产生的经济社会价值的乘积。选择容量价值将经济发展状况和资源环境状况融合了起来,实现了经济社会发展与生态环境保护的价值统一,这对于推进保护与发展相辅相成的生态文明建设具有积极意义。为了探索以选择容量价值为指标的生态补偿标准与自然资源资产价值核算框架和核算方法,以珠江流域水资源供应为例,对跨水文单元的水资源供应流动进行了生态补偿核算,对各水文单元的水资源供应的自然资源资产价值进行了量化评估研究。研究结果显示,珠江三角洲地区的水资源供应的选择容量价值大部分(约74%)来自上游水文单元的跨区输入,而上游水文单元所提供的水资源供应的选择容量价值也在相当程度上依赖于下游水文单元的经济社会发展。基于跨区流动的水资源供应的选择容量价值,可以按照"共享共担"和"同工同酬"原则进行跨区生态补偿核算;基于各水文单元所提供的水资源供应的选择容量价值,可以对各单元内自然资源资产价值进行核定,这对于协调区域发展推进西江-珠江经济带流域生态文明...  相似文献   

11.
厘清生态系统服务权衡关系的驱动因素对实现生态系统高效管理至关重要。然而,在不同气候区生态系统服务权衡关系在空间上如何变化及其驱动机制是否一致,尚不清楚。以川滇-黄土高原生态屏障带为例,基于InVEST模型、CASA模型评估生态系统服务空间分布特征,采用RMSE量化生态系统服务权衡关系,利用地理探测器探究不同气候区生态系统服务权衡的驱动机制,以期为生态系统管理提供参考依据。结果如下:(1)不同生态系统服务在不同气候区存在明显差异,WY整体由东北向西南呈递减趋势,NPP和SC呈现由北向南递减的趋势。(2)WY∩NPP的权衡最高值在中温带为0.317,最低值在高原气候区为0.181。WY∩SC在不同气候区RMSE变化幅度较小,由南向北呈现递减趋势;中亚热带气候区WY∩SC的权衡程度最高,为0.295,南温带的权衡程度最低,为0.229。NPP∩SC的RMSE差值最小,仅有0.064,高原气候区权衡程度略低于温带和亚热带。(3)在不同气候区自然因素对权衡关系作用显著高于社会因素,但在人口密集区,人为活动可以部分突破自然因素的约束,使其对权衡的影响有所提升。因此,在制定不同气候区生态系统服务管理...  相似文献   

12.
粟晓玲  康绍忠  佟玲 《生态学报》2006,26(6):2011-2019
Costanza等提出的单位面积生态系统服务价值没有考虑生态系统服务的空间异质性,是与生态系统结构和功能有关的生态系统本身的价值,这里称为静态价值。在实际应用于指导以社会、经济、生态综合效益最大为目标的流域水土资源优化配置决策时,不能反映资源的稀缺程度和随社会经济发展水平变化的对生态价值的支付意愿,使得静态生态价值的研究成果难以得到应用。提出了动态生态价值的概念,某一特定区域生态系统服务的动态价值是指其相应的生态服务功能在特定人群一定支付意愿下的现实价值。在Costanza等人提出的单位面积生态价值的基础上,考虑生态类型的覆盖度等特点结合专家咨询法提出了林地、草地单位面积生态价值的修正系数,估算流域生态系统服务的静态生态价值;建立了基于发展阶段系数和资源紧缺度的生态价值动态估算方法。以甘肃河西走廊石羊河流域为例,估算出2000年流域生态系统服务的静态价值为4.17亿美元,相当于当年流域GDP的0.3657倍,且在空间上呈现从上游山区向下游荒漠区递减的规律;动态生态价值为2.35亿美元,下游和上游大,中游较小。动态生态价值的研究为生态价值研究成果进一步在资源合理配置中的应用提供了途径。  相似文献   

13.
生态管理分区是建设用地扩张指引和生态空间管控的重要依据,对维护区域生态安全和生态文明建设具有重要意义。以我国北方沿海重要中心城市——大连市为例,选取食物供给、水源涵养、固碳释氧、土壤保持、生境维持和美学景观6项指标,综合运用模型法及生态经济学方法量化生态系统服务供给,并结合土地利用、人口和经济现状定量评估2015年生态系统服务需求。利用象限匹配法和耦合协调度模型,探究千米网格尺度下生态系统服务供需匹配关系和协调关系及其区域差异,进而通过空间叠置分析划分生态管理分区并提出相应管理措施,旨在为区域内生态修复以及差异化建设提供科学参考。研究结果表明:①大连市生态系统服务供需具有显著空间异质性,总体呈现北部林地和东西部沿海生态系统服务供给高、需求低,中南内陆城镇区生态系统服务供给低、需求高的空间格局;②生态系统服务供需不匹配和失调特征明显,匹配类型以高供给-低需求和低供给-高需求为主,生态系统服务供需耦合协调度平均值为0.38,表现为轻度失调;③综合分析将大连分为4个生态管理区,其中,生态涵养区为高供低需-供需失调区,要以保护为主培育为辅,重点保护;生态农业区为高需-供需平衡区,以生态保护和生态建设为主,提高其投入产出效率;生态改良为低供高需-供需失调区,以生态建设和整治为主,综合改善生态系统服务水平;生态一般保护区为高供-供需失调区,以综合保护为主,提高生态溢出效应。  相似文献   

14.
15.
补偿标准是生态补偿项目研究的核心内容。为提高补偿标准的可操作性,以渭河干流甘肃段为研究区,基于流域生态补偿标准范围界定,在考虑耕地向多种林地转化情况下采用In VEST模型和加权法核算流域新增生态服务量,并以新增生态服务价值为补偿上限,农户机会成本为补偿下限,先从国家新一轮退耕还林政策导向视角,探讨15°—25°和25°以上坡耕地退耕还林的差异化补偿标准。再从利益公平分配视角,耦合机会成本投入与生态系统服务产出,探讨生态补偿净收益不同地区的差异化补偿标准。结果表明:(1)渭河干流甘肃段退耕还林,生态补偿标准范围为146.39—481.98万元km~(-2)a~(-1)。(2)重要水源地一级保护区和保留区迎水面15°—25°坡耕地全部退耕还林需补偿金额13.95—33.55亿元。25°以上坡耕地全部退耕还林需要补偿金额12.96—28.35亿元。(3)各县/区比较,退耕还林净收益麦积区最大,陇西县最小。其生态补偿范围分别为202.23—727.92、96.99—136.53万元km~(-2)a~(-1)。  相似文献   

16.
李慧杰  牛香  王兵  赵志江 《生态学报》2020,40(13):4316-4326
生态系统服务功能与景观格局演变关系极为密切,研究生态系统服务功能与景观格局的耦合协调度对于区域发展具有重要意义。以武陵山区退耕还林工程为例,参照国家标准和行业标准,采用分布式测算方法、景观格局指数分析和耦合协调度模型等方法,旨在揭示武陵山区退耕还林工程生态系统服务功能与景观格局二者耦合协调关系。结果表明:(1)2005—2017年间武陵山区退耕还林工程各项生态服务功能物质量均以15倍左右速度增长,生态系统服务空间分布格局最佳区域由西部地区逐渐向东南扩大;(2)武陵山区景观演变存在时空差异,1995—2005年景观格局变化更为明显,变化区域集中在中西部地区,2005—2015年与之相比,景观格局变化空间上更为分散;(3)武陵山区退耕还林工程生态系统服务与景观格局演变存在较高水平的耦合以及高水平的协调性。研究结果可为武陵山区土地利用规划及退耕还林工程进一步实施提供科学依据。  相似文献   

17.
Trophic cascade hypotheses for biological communities, linking predation by upper trophic levels to major features of ecological structure and dynamics at lower trophic levels, are widely subscribed and may influence conservation policy. Few such hypotheses have been evaluated for temporal or spatial generality. Previous studies of sea otter (Enhydra lutris) predation along the outer coast of North America suggest a pattern, often elevated to the status of paradigm, in which sea otter presence leads to reduced sea urchin (Strongylocentrotus spp.) biomass and rapid increases in abundance and diversity of annual algal species, followed by a decline in diversity as one or a few perennial algal species become dominant. Both sea otter predation and commercial sea urchin harvest are ecologically and economically important sources of urchin mortality in nearshore benthic systems in northern Washington marine waters. We recorded changes in density of macroalgae in San Juan Channel, a marine reserve in the physically protected inland waters of northern Washington, resulting from three levels of experimental urchin harvest: (1) simulated sea otter predation (monthly complete harvest of sea urchins), (2) simulated commercial urchin harvest (annual size-selective harvest of sea urchins), and (3) no harvest (control). The two experimental urchin removal treatments did not significantly increase the density of perennial (Agarum and Laminaria) or annual (Desmarestia, Costaria, Alaria and Nereocystis) species of macroalgae after 2 years, despite significant and persistent decreases in urchin densities. Our results suggest that other factors such as grazing by other invertebrates, the presence of dense Agarum stands, and recruitment frequency of macroalgae and macroinvertebrates may play a large role in influencing community structure in San Juan Channel and other physically protected marine waters within the range of sea otters. Handling editor: J. Trexler  相似文献   

18.
《Ecological Indicators》2008,8(2):170-179
There are many fruit trees that could be integrated into dryland farming systems in Sub-Saharan Africa to support income and nutritional security. Fruit contains almost all known vitamins and many essential minerals. Five important fruit species that are cross-regional include: Adansonia digitata, Tamarindus indica, Zizyphus mauritiana, Sclerocarya birrea, and Mangifera indica. While these species are well integrated in the Sahel region, besides mango, they are generally absent from smallholder farms in East and Central Africa. Fruits of the species in this region are mostly harvested unsustainably from the wild communal areas. Unlike the situation in the neighboring Southern Africa region, where S. birrea is utilized extensively in the wine industry, there is virtually no use for the tree in this region, largely because of limited knowledge. Z. mauritiana use is also limited because of low quality germplasm—the hard stone clings to the flesh. An analytical framework based on five factors (site requirements, genetic variability, propagation methods, nutritional properties and utilization, and commercial potential) is used to compare knowledge status and gaps on the species in the region. While this analysis reveals the existence of considerable knowledge between and within the species, lack of improved germplasm and markets emerge as two key constraints limiting their conservation through on-farm planting. Key research and development needs identified are: (a) fostering cross-collaboration and knowledge exchange with other regions where the species are fairly well utilized, and (b) developing criteria and indicators for monitoring impacts and increased investments on the “Big Five” on livelihood of dryland communities and on biodiversity conservation.  相似文献   

19.
Swans, geese and some ducks (Anatidae) are obligate herbivores, many are important quarry species and all contribute to a variety of ecosystem services. Population growth and shifting ranges have led to increasing proximity to man and thus increasing conflicts. We review and synthesize the role of these birds as herbivores on agricultural land (cropland, rotational grassland and pasture) and other terrestrial habitats where conflict with human interests may occur. A bibliographic analysis of peer‐reviewed papers (N = 359) shows that publication activity peaked in 1991–2000 in North America and 2000–2010 in Europe, and has decreased since. Taxonomic and geographical biases are obvious in research to date: Snow Goose Chen caerulescens was the most studied species (N = 98), and Canada Branta canadensis, Barnacle B. leucopsis and Brent geese B. bernicla all featured in more than 40 studies; most studies originated in northwest Europe or North America, very few have been carried out in Asia and European Russia. On the basis of nutrient/energy budgets of herbivorous waterfowl, it is evident that dense single‐species crops (such as rotational grassland, early‐growth cereals and root crops) and spilled grain in agricultural landscapes offer elevated energetic and nutritional intake rates of food of higher quality compared to natural or semi‐natural vegetation. Hence, although affected by seasonal nutritional demands, proximity to roost, field size, disturbance levels, access to water, food depletion and snow cover, agricultural landscapes tend to offer superior foraging opportunities over natural habitats, creating potential conflict with agriculture. Herbivorous waterfowl select for high protein, soluble carbohydrate and water content, high digestibility as well as low fibre and phenolic compounds, but intake rates from grazing varied with goose body and bill morphology, creating species‐specific loci for conflict. Crop damage by trampling and puddling has not been demonstrated convincingly, nor do waterfowl faeces deter grazing stock, but where consumption of crops evidently reduces yields this causes conflict with farmers. Studies show that it is difficult and expensive to assess the precise impacts of waterfowl feeding on yield loss because of other sources of variation. However, less damage has been documented from winter grazing compared to spring grazing and yield loss after spring grazing on grassland appears more pronounced than losses on cereal fields. Although yield losses at national scales are trivial, individual farmers in areas of greatest waterfowl feeding concentrations suffer disproportionately, necessitating improved solutions to conflict. Accordingly, we review the efficacy of population management, disturbance, provision of alternative feeding areas, compensation and large‐scale stakeholder involvement and co‐management as options for resolving conflict based on the existing literature and present a framework of management advice for the future. We conclude with an assessment of the research needs for the immediate future to inform policy development, improve management of waterfowl populations and reduce conflict with agriculture.  相似文献   

20.
Indigenous forest reserves represent approximately one fifth of Brazilian Amazonia and pose enormous challenges for sustainable natural resource management by native Amazonians. In collaboration with the Kayapó Indians of A’Ukre of southeastern Amazonia, we obtained a game harvest profile of over 1360 forest vertebrates consumed at this village over a 20-month period, including 743 mammals, 361 forest tortoises and 256 birds from a minimum of 42 game species. This amounted to a total of 13,775 kg of game animals harvested over the entire study (mean = 26.2 kg d−1). We also obtained some 450 km of line transect census data of midsized to large-bodied vertebrates within the core hunting catchment of this village and in an unhunted but otherwise comparable site upriver of A’Ukre. Population density estimates of 16 of the 18 species censused were significantly depressed by hunting by central place foragers within the village catchment, and a number of harvest-sensitive prey species showed clear evidence of local depletion. For the time being, however, we can conclude that hunting was sustainable at the landscape scale largely because source-sink dynamics in the context of low village catchment density is made possible by large surrounding tracts of primary forest that remain unharvested or underharvested.  相似文献   

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