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1.
Nature reserves have developed rapidly over the decades in China and play a significant role in the function of ecosystem services. The function of ecosystem services in nature reserves, however, has tended to decline in recent years due to natural hazards and human activities. Based on land use, the variation of ecosystem services value (ESV) during 2000–2010 in national nature reserves in Sichuan was evaluated. We analyzed the comprehensive effects of natural disasters and human activities on the decline of ESVs. Total ESV in the national nature reserves in Sichuan was approximately 2741.35 million US$ in 2000, 2616.81 million US$ in 2005, and 2499.06 million US$ in 2010, representing a decrease of 242.29 million US$, or 8.84%, in the decade. Forestland, grassland, wetland, and water bodies played vital roles in the function of ecosystem services, with an aggregated ESV of 99% of the total. The largest proportion of the total ESV was the protection of biodiversity at 48.6%. ESV of all land use types and single ecosystem services continued to decline during 2000–2010. A mechanism of adaptable risk prevention should be established, and unreasonable human activities should be avoided to protect ecosystems and to improve the functions of ecosystem services.  相似文献   

2.
A generic input-state-output scheme has been used to represent ecosystem dynamics. Systemic approaches to ecosystems use functions that are based either on inputs, state or outputs of the system. Some examples of approaches that use a combination of functions have been recently proposed. For example the use of eco-exergy to emergy flow can be seen as a mixed input-state approach; more recently, to connect the state to the output of the ecosystem, the relation of eco-exergy and ecosystems services has been proposed. This paper studies the link between the useful output of an ecosystems and its input through the relation between ecosystem services and emergy flow, in a kind of grey/black box scheme (i.e., without considering the state and the structure of the ecosystem). No direct connection between the two concepts can be determined, but identifying and quantifying the emergy flows feeding an ecosystem and the services to humans coming from them facilitate the sustainable conservation of Nature and its functions. Furthermore, this input-output relation can be established in general by calculating the ratio of the value of the ecosystem services to the emergy flow that supports the system. In particular, the ratio of the world ecosystem services to the emergy flow supporting the entire biosphere has been calculated showing that, at least at the global level, Nature is more efficacious in producing “money” (in form of ecosystem services) than economic systems (e.g., national economies and their GDP).  相似文献   

3.
Erosion control is one of the most important functions of forest ecosystems, and its accurate assessment is useful to illuminate the importance of forest ecosystem services for humans so as to rationally conserve forest resources. This paper examines Zhangjiajie National Forest Park, the first national forest park in China, to seek practical methods for assessment of the forest erosion control function using a geographical information system (GIS). The results show that the potential and actual amounts of soil erosion are 2.92 million ton and 0.14 million ton per year, respectively, in Zhangjiajie National Forest Park. The total reduction in soil loss reaches 2.77 million ton per year with the existence of a forest ecosystem. The erosion control function of near mature, mature and over mature broadleaf forest is excellent, and natural forest conservation and natural restoration of the degraded forest ecosystem can provide the largest benefits in soil erosion control. Nearly all the near mature, mature and over-mature forest in the park is at the top and in steep mountain areas, and could be rationally cut and utilized by local communities, but extensive timber felling should be strictly prohibited.  相似文献   

4.
• US tin use decreases as the GDP value added by manufacturing sector increases. • Global and China’s tin use increases as the GDP added by manufacturing increases. • A sigmoid curve can fit the US tin use data well. • US tin use patterns is not due to the finite tin reserves or resources. • Policies, substitutions, etc. play key roles in the changing tin use patterns. Tin is of key importance to daily life and national security; it is considered an essential industrial metal. The United States (US) is the world’s largest economy and consumer of natural resources. Therefore, the analysis of historical tin use in the US is helpful for understanding future tin use trends in the world as a whole and in developing countries. Time series analysis, regression analysis with GDP or GDP/capita, and historical data fitted with logistic and Gompertz models are employed in this study. Historical tin use in the US shows three stages—increase-constant-decrease, as GDP per capita has increased. Tin use in the US is negatively correlated with the GDP value added by the manufacturing sector, while the use of tin worldwide and in China continues to increase along with the GDP value added by the manufacturing sector. Although a sigmoid curve can fit the US tin use data well, that use is not directly related to the limited tin reserves or resources. Rather, policies, economic restructuring, substitutions, new end-use markets, etc. have played key roles in the changing tin use patterns. This work contributes to understanding future tin use at both the global and national levels: tin use will continue to increase with GDP at the global level, but use patterns of tin at the national level can be changed through human intervention.  相似文献   

5.
Terrestrial ecosystems store more carbon (C) than the atmosphere and provide ecosystem services (ES) such as global climate regulation, by sequestering carbon within biomass and soil. Land use land cover (LULC) change is considered a key factor, playing an important role in the dynamic variations of carbon storage. The aim of this paper is to assess the effects that LULC has had on carbon stocks and consequently on climate change regulation in north-western Morocco over 21 years. To achieve this aim, the Integrated Valuation of ES and Trade-offs (InVEST) model is used to assess status and variation in the net amount of carbon stored by the different types of LULC, and the economic value of the carbon sequestered in the remaining stock. The results show that the total carbon stock increased from 4.81TgC in 1996 to 4.98TgC in 2017. Over the 21 years, the LULC changes had the greatest effect on carbon storage - an increase of 6.87% with 0.17TgC of carbon sequestered, since the majority of unused land was changed to forest and cultivated land. Based on the global costs of atmospheric carbon, we estimate the economic value of carbon storage services to be between US$1,800,000 and US$3,570,000 for the whole period, with an average yearly increment of between US$86,000 and US$170,000. The results show that the ecosystem management has had a substantial climate mitigation effect. Also, the possibility of paying for ES could inform policy on the adoption of LULC to support livelihood and management choices.  相似文献   

6.
Abstract: Global declines in biodiversity and the widespread degradation of ecosystem services have led to urgent calls to safeguard both. Responses to this urgency include calls to integrate the needs of ecosystem services and biodiversity into the design of conservation interventions. The benefits of such integration are purported to include improvements in the justification and resources available for these interventions. Nevertheless, additional costs and potential trade‐offs remain poorly understood in the design of interventions that seek to conserve biodiversity and ecosystem services. We sought to investigate the synergies and trade‐offs in safeguarding ecosystem services and biodiversity in South Africa's Little Karoo. We used data on three ecosystem services—carbon storage, water recharge, and fodder provision—and data on biodiversity to examine several conservation planning scenarios. First, we investigated the amount of each ecosystem service captured incidentally by a conservation plan to meet targets for biodiversity only while minimizing opportunity costs. We then examined the costs of adding targets for ecosystem services into this conservation plan. Finally, we explored trade‐offs between biodiversity and ecosystem service targets at a fixed cost. At least 30% of each ecosystem service was captured incidentally when all of biodiversity targets were met. By including data on ecosystem services, we increased the amount of services captured by at least 20% for all three services without additional costs. When biodiversity targets were reduced by 8%, an extra 40% of fodder provision and water recharge were obtained and 58% of carbon could be captured for the same cost. The opportunity cost (in terms of forgone production) of safeguarding 100% of the biodiversity targets was about US$500 million. Our results showed that with a small decrease in biodiversity target achievement, substantial gains for the conservation of ecosystem services can be achieved within our biodiversity priority areas for no extra cost.  相似文献   

7.
基于遥感与GIS的黄河三角洲绿色空间生态服务价值评估   总被引:2,自引:0,他引:2  
刘庆  李伟  陆兆华 《生态环境》2010,19(8):1838-1843
基于黄河三角洲1987、1997和2007年的TM遥感影像解译数据和野外调查结果,得到研究区三个年度的土地利用空间分布图。然后从土地利用的角度重新审视绿色空间的概念和内涵,建立基于土地利用类型的绿色空间生态评估体系,分析黄河三角洲地区的绿色空间生态服务价值及其变化情况。研究结果表明,1987—2007年间黄河三角洲地区绿色空间土地利用变化显著,其中,水体面积增加明显,农田、林地面积略有增加,湿地和草地面积显著减少,未利用地面积略有减少。土地利用面积的变化直接影响到其生态服务价值的变化,研究期间湿地生态服务价值减少了77.72亿元,草地减少9.00亿元,未利用地减少0.16亿元;水体的生态服务价值增加54.54亿元,农田和林地共增加3.41亿元。研究区绿色空间生态服务价值呈逐年减少的趋势,20年间研究区生态服务价值减少了28.94亿元。通过对绿色空间单项生态服务价值功能重要性进行评价,研究表明黄河三角洲地区单项生态服务价值以湿地、农田和水体占主要地位,这与各单项生态系统的面积及其单位生态服务价值量有关。  相似文献   

8.
Urban forests provide important ecosystem services, such as urban air quality improvement by removing pollutants. While robust evidence exists that plant physiology, abundance, and distribution within cities are basic parameters affecting the magnitude and efficiency of air pollution removal, little is known about effects of plant diversity on the stability of this ecosystem service. Here, by means of a spatial analysis integrating system dynamic modeling and geostatistics, we assessed the effects of tree diversity on the removal of tropospheric ozone (O3) in Rome, Italy, in two years (2003 and 2004) that were very different for climatic conditions and ozone levels. Different tree functional groups showed complementary uptake patterns, related to tree physiology and phenology, maintaining a stable community function across different climatic conditions. Our results, although depending on the city-specific conditions of the studied area, suggest a higher function stability at increasing diversity levels in urban ecosystems. In Rome, such ecosystem services, based on published unitary costs of externalities and of mortality associated with O3, can be prudently valued to roughly US$2 and $3 million/year, respectively.  相似文献   

9.
Abstract: Following creation of the 2010 Biodiversity Target under the Convention on Biological Diversity and adoption of the United Nations Millennium Development Goals, information on status and trends of biodiversity at the national level has become increasingly important to both science and policy. National red lists (NRLs) of threatened species may provide suitable data for reporting on progress toward these goals and for informing national conservation priority setting. This information will also become increasingly important for developing species‐ and ecosystem‐based strategies for climate change adaptation. We conducted a thorough global review of NRLs in 109 countries and analyzed gaps in NRL coverage in terms of geography and taxonomy to determine priority regions and taxonomic groups for further investment. We then examined correlations between the NRL data set and gross domestic product (GDP) and vertebrate species richness. The largest geographic gap was in Oceania, followed by middle Africa, the Caribbean, and western Africa, whereas the largest taxonomic gaps were for invertebrates, fungi, and lichens. The comprehensiveness of NRL coverage within a given country was positively correlated with GDP and negatively correlated with total vertebrate richness and threatened vertebrate richness. This supports the assertion that regions with the greatest and most vulnerable biodiversity receive the least conservation attention and indicates that financial resources may be an integral limitation. To improve coverage of NRLs, we propose a combination of projects that target underrepresented taxa or regions and projects that provide the means for countries to create or update NRLs on their own. We recommend improvements in knowledge transfer within and across regions as a priority for future investment.  相似文献   

10.
重复计算一直是困扰湿地生态系统服务价值评价的一个难点问题。湿地生态系统服务的复杂性及其组成分的非线性容易导致在计算湿地生态系统服务价值时容易导致重复计算,如果不能正确的去除湿地生态系统服务价值评价中重复计算的部分,会使评估结果的可信度降低。湿地生态系统服务价值评价的重复性计算主要体现在两个方面,总服务价值评价中的重复计算和部分服务之间的重复计算。湿地生态系统服务由湿地生态系统和生物多样性产生,并为人类福祉做出贡献,在这一过程中,湿地生态系统功能与服务的复杂的关系及服务之间的因果关系容易导致在计算生态系统总的服务价值时重复计算的产生,也就是分类时存在重复计算。部分服务之间的重复计算则主要是由于指标的模糊不清、参数的重复和评价方法的选择导致的。通过分析湿地生态系统服务价值评价重复性计算产生的原因,文章提出了一个具体的解决框架,包括最终服务的确定、指标的明确、模型的构建以及评估方法的选择等。首先,将湿地生态系统服务分成中间服务和最终服务,以最终服务作为最终要评价的服务;其次,针对部分服务中可能存在的重复计算,从指标和参数的明确、评价方法的选择和数学模型的构建等方面进行解决;最后,构建一个优化的湿地生态系统服务价值评价体系。希望通过这些解决办法来降低湿地生态系统服务价值评价中重复计算的可能性,以期更加准确的评估湿地生态系统服务。  相似文献   

11.
条件价值评估法(CVM)是当前可用于确定环境物品非市场的和非使用价值的有效方法.在分析南昌市城市河湖生态环境问题的基础上,采用条件价值评估法,共回收194份单边界二分式CVM有效问卷,研究了南昌城市河湖生态系统服务改善的支付意愿及其经济价值.研究表明:1)南昌市城区河湖生态系统服务改善的平均支付意愿约为105.83元/...  相似文献   

12.
在分析流溪河流域白云区段生态系统的景观变化和生态环境现状的基础上,依据流溪河流域白云区段的土地详查数据(1993年)及其土地利用变更调查数据(2001年末),引用Constanza等对全球生态系统服务单位公顷价值的平均估算结果,对流溪河流域白云区段生态系统服务价值进行评估。评估结果表明:2001年流溪河流域白云区段生态系统服务的总价值为85190050.43美元,折合人民币70700.75万元,相当于该区域同期GDP的6.22%。由于存在影响核算结果准确性的一些因素,因此,该结果是粗略与保守的估算。  相似文献   

13.
王彤  王留锁  姜曼 《生态环境》2010,26(6):1439-1444
生态补偿标准的测算是建立生态补偿机制的核心问题,也是难点所在。研究在对现有生态补偿标准计算方法进行总结分析的基础上,分别从供给方和需求方的角度探索建立了水库流域生态补偿标准测算体系。该体系对基于水库上游水源涵养区生态系统服务功能、生态保护建设总成本和基于下游用水城市意愿支付价格的补偿标准进行了比较分析,最终选择一个既能使水消费者承受得起,又能使生态保护者体会到有所回报的补偿金数额作为上下游协商确定补偿标准的依据。此体系较为全面地对补偿标准进行了测算,使得补偿标准更为公平、合理,进一步完善了水库流域生态补偿标准测算方法。并以大伙房水库流域为例,对其补偿标准进行测算,得出基于研究区生态系统服务功能的补偿标准为64661.3万元,基于研究区生态保护建设总成本的补偿标准为9221.4万元,基于下游用水城市意愿支付价格的补偿标准分别为8637.6万元、12956.4万元,最终认为10000万元是令补偿双方都比较容易接受的一个价格,可作为确定补偿标准的依据。  相似文献   

14.
大连市森林生态系统服务功能评估   总被引:1,自引:0,他引:1  
为客观度量森林生态系统服务功能,依据2003年大连市土地利用图形数据,参照国家林业局发布的《森林生态系统服务功能评估规范》(LY/T1721-2008)标准中的评估方法,基于G IS技术对大连市森林生态系统服务功能及其空间差异性进行定量评价。结果表明:(1)大连市森林生态系统服务功能的经济价值总计为197.91亿元/a,其中涵养水源、保育土壤、固碳释氧、净化大气4种生态服务功能的经济价值比例分别为35.3%、16.7%、43.0%、5.0%;(2)大连市的生态屏障庄河市、普兰店市和瓦房店市具有显著的森林生态系统服务功能,其价值比例分别为32.6%、21.8%和25.8%,而长海县、金州区、旅顺口区、甘井子区、沙河口区、中山区、西岗区森林生态系统服务功能的经济价值比例分别为0.9%、7.8%、5.7%、3.9%、0.2%、0.5%和0.7%。  相似文献   

15.
城市生态系统服务功能的价值结构分析   总被引:28,自引:0,他引:28  
本文从城市生态系统价值体系出发,探讨城市自然资本,经济资本和社会资本综合测算的理论与方法,结果表明:示范区的自然总资本以年均4%的速度递减,其真实总资本年均增长率为4.5%而不是国内生产总值的12.6%,自然资本的增减应成为衡量一个城市或区域是否实现可持续发展的核心指标。城市生态系统中自然资本由持续递减变为递增,是实现人类共同追求的可持续发展目标必由之路。  相似文献   

16.
This analysis estimates willingness to pay to improve community-based rural water utilities in the Dodoma and Singida Regions of Central Tanzania, using Multinomial Logit functions. An estimate of willingness to pay provides an indication of the demand for improved services and potential for them being sustainable. Surveys were conducted in a total of 30 villages in the two regions. In the Dodoma Region, about 14% of respondents indicated that they were satisfied with the status quo, 64% suggested increasing water discharge and watering points, and 22% proposed other improvements relating to water quality. In the Singida Region, 31% of the respondents were satisfied with the status quo, 59% wanted deeper boreholes and watering points, and 10% indicated other types of improvement relating to water quality. The Multinomial Logit functions indicated that the interaction between the water quality variable and proposed bids were important in making choices with reference to the type of improvement desired. Respondents who wanted to increase water supply in Dodoma Region were willing to pay 32 Tsh above the existing tariff of 20 Tsh/bucket. In the Singida Region, the analogous amount was 91 Tsh per household per year above the existing user fee of 508 Tsh per household per year. If the tariff or user fees have to be increased, the estimated average potential revenue for the surveyed villages was 252 million Tsh/year (US$265 263) in the Dodoma Region, and 5.2 million Tsh/year (US$5474) in the Singida Region. In the future, strategic planning is needed to ensure that improvements proposed potentially improve cost recovery initiatives and increase the level of consumer satisfaction. Also, care will be needed to ensure that more disadvantaged community members do not suffer unduly from increases in tariff or user fees.  相似文献   

17.
An emergy evaluation was carried out to assess the carrying capacity of a small, uninhabited island (Woosedo) off the southwestern coast of Korea. The sea area within 1 km from the high tide level of the island was included in the evaluation. The total environmental emergy input to Woosedo was 1.66E19 sej/yr, with the most emergy contribution from the tidal energy. The land and marine ecosystems of Woosedo contributed 4.97 million Em$ (7600 Em$/ha/yr) to the Korean economy annually. If Woosedo was developed to the national average at the emergy investment ratio of 2.86, its carrying capacity was estimated at 1034 people at the current living standard of Korea. With this population, the island system would not be sustainable with a very low emergy sustainability index of 0.36. At the same living standard used in the developed scenario, the carrying capacity of the island would be 370 people for a sustainable development scenario and 270 people if the renewable emergy were the only source to support the population. The emergy contribution of the marine ecosystem of the island was the major source of support in determining the level of carrying capacity of the island.  相似文献   

18.
Pollinator declines have prompted efforts to assess how land-use change affects insect pollinators and pollination services in agricultural landscapes. Yet many tools to measure insect pollination services require substantial landscape-scale data and technical expertise. In expert workshops, 3 straightforward methods (desk-based method, field survey, and empirical manipulation with exclusion experiments) for rapid insect pollination assessment at site scale were developed to provide an adaptable framework that is accessible to nonspecialist with limited resources. These methods were designed for TESSA (Toolkit for Ecosystem Service Site-Based Assessment) and allow comparative assessment of pollination services at a site of conservation interest and in its most plausible alternative state (e.g., converted to agricultural land). We applied the methods at a nature reserve in the United Kingdom to estimate the value of insect pollination services provided by the reserve. The economic value of pollination services provided by the reserve ranged from US$6163 to US$11,546/year. The conversion of the reserve to arable land would provide no insect pollination services and a net annual benefit from insect-pollinated crop production of approximately $1542/year (US$24∙ha–1∙year–1). The methods had wide applicability and were readily adapted to different insect-pollinated crops: rape (Brassica napus) and beans (Vicia faba) crops. All methods were rapidly employed under a low budget. The relatively less robust methods that required fewer resources yielded higher estimates of annual insect pollination benefit.  相似文献   

19.
The ecosystem of munseom area (MA) in Jeju Island, one of the marine protected areas in South Korea, has been continuously threatened by lack of management and pollution of the surrounding sea area. As a result, the South Korean government is trying to implement the systematic management plan to conserve the marine ecosystem of the MA. This article tries to obtain information about the conservation value of the MA. To this end, this study examines household willingness to pay (WTP) for conserving the MA employing the contingent valuation (CV) approach. A total of 1000 South Korean households were involved in the CV survey using a dichotomous choice question. The mean yearly WTP for the conservation is estimated as KRW 1763 (USD 1.50) per household. The national value expanded from the sample to the population is worth KRW 34.0billion (USD 29.0 million) per year. The results imply that the conservation is supported by South Korean households.  相似文献   

20.
Abstract: Subsistence hunting affects vast tracts of tropical wilderness that otherwise remain structurally unaltered, yet distinguishing hunted from nonhunted tropical forests presents a difficult problem because this diffuse form of resource extraction leaves few visible signs of its occurrence. I used a standardized series of line-transect censuses conducted over a 10-year period to examine the effects of subsistence game harvest on the structure of vertebrate communities in 25 Amazonian forest sites subjected to varying levels of hunting pressure. Crude vertebrate biomass, which was highly correlated with hunting pressure, gradually declined from nearly 1200 kg km−2 at nonhunted sites to less than 200 kg km−2 at heavily hunted sites. Hunting had a negative effect on the total biomass and relative abundance of vertebrate species in different size classes at these forest sites, but it did not affect their overall density. In particular, persistent hunting markedly reduced the density of large-bodied game species (>5 kg), which contributed a large proportion of the overall community biomass at nonhunted sites (65–78%) and lightly hunted sites (55–71%). Nutrient-rich floodplain forests contained a consistently greater game biomass than nutrient-poor unflooded forests, once I controlled for the effects of hunting pressure. Conservative estimates of game yields indicate that as many as 23.5 million game vertebrates, equivalent to 89,224 tons of bushmeat with a market value of US$190.7 million, are consumed each year by the rural population of Brazilian Amazonia, which illustrates the enormous socioeconomic value of game resources in the region. My cross-site comparison documents the staggering effect of subsistence hunters on tropical forest vertebrate communities and highlights the importance of considering forest types and forest productivity in game management programs.  相似文献   

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