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1.
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   

2.
Ecological Sustainability as a Conservation Concept   总被引:3,自引:0,他引:3  
Neither the classic resource management concept of maximum sustainable yield nor the concept of sustainable development are useful to contemporary, nonanthropocentric, ecologically informed conservation biology. As an alternative, we advance an ecological definition of sustainability that is in better accord with biological conservation: meeting human needs without compromising the health of ecosystems. In addition to familiar benefit-cost constraints on human economic activity, we urge adding ecologic constraints. Projects are not choice-worthy if they compromise the health of the ecosystems in which human economic systems are embedded. Sustainability, so defined, is proffered as an approach to conservation that would complement wildlands preservation for ecological integrity, not substitute for wildlands preservation.  相似文献   

3.
保护性耕作土壤线虫成熟度及区系分析   总被引:1,自引:0,他引:1  
土壤线虫的生活史和功能多样性能够反映土壤健康质量和生态环境的演变,耕作措施的改变可能通过影响土壤环境进而影响土壤线虫的生活史和功能多样性,然而关于保护性耕作条件下土壤线虫成熟度及区系分析的研究,国内外尚鲜见报道。为了深入揭示土壤线虫对保护性耕作土壤生态环境变化的生物指示作用,以辽宁彰武县保护性耕作示范推广基地土壤为研究对象,通过实地调查和取样分析,对比研究了传统犁耕和6年保护性耕作(免耕秸秆覆盖)条件下的土壤线虫成熟度指数及区系分析。研究发现,与犁耕相比,保护性耕作显著降低了表层土壤自由生活线虫成熟指数MI、总成熟指数MMI、c-p值为2~5的自由生活线虫成熟指数MI2–5和总成熟指数MMI2–5,降低幅度分别为11%、9%、9%和10%,然而对植物寄生线虫成熟指数PPI以及PPI/MI比值的影响不明显。线虫区系分析结果表明,保护性耕作土壤线虫的富集指数EI和结构指数SI,比犁耕土壤分别显著降低56%和24%。保护性耕作造成的土壤pH降低和可能带来的土壤农药污染,可能是导致其上述影响的主要原因。简单相关分析和主成分分析结果证明,线虫成熟指数MI、MMI、MI2–5和MMI2–5以及结构指数SI与土壤pH关系密切。综上,土壤线虫生活史多样性和功能多样性对于揭示保护性耕作对土壤环境的影响具有良好的作用。  相似文献   

4.
Abstract: Frustration with the lack of action on conservation issues by governments has sparked debate around the policy role of conservation biologists. We analyzed the political economy of conservation biology, that is, of the dynamics of the political and economic structures within which conservation biology operates, and we suggest more productive means for conservation biologists to achieve conservation goals. Within the modern state, conservation goals are marginalized because the growth needs of industrial capital have the highest priority. Environmental advocacy within this system largely addresses only proximate concerns and has limited success. Science is a product of modern society, but scientists now need to foster novel institutional arrangements in which humans can function within the limits of natural systems. This entails a larger recognition of the inherent contradictions residing within current institutions that themselves depend on unsustainably high resource flows. As one critical counterbalance to these institutions, we discuss community-based management and research as primary institutions through which sustainable use of natural resources might be achieved.  相似文献   

5.
Starting from the concept of three fundamental sustainability dimensions (environmental, social, and economic), this study investigated professional contributions to sustainability by means of principal component analysis (PCA). Graduates from the Environmental Sciences program (N?=?542) at ETH Zurich described their best professional contributions to sustainable development. Next, they evaluated whether their best practice example contributed to achieving any of the five environmental, social, and economic objectives of the Swiss national sustainability strategy. These judgments served as the basis for a PCA aiming to identify principal sustainability components (PSCs) covering typical synergies between sustainability objectives within and transcending the three fundamental dimensions. Three PSCs capturing important synergies were identified. PSC 1 Product and Process Development reflects how ecological innovation and modernization can generate social and economic benefits and at the same time facilitate the reduction in use of as well as the responsible use of natural resources. PSC 2 Education and Social Economics reflects how educational activities and sociocultural sustainability initiatives can simultaneously promote income and employment, social and human capital, and free personal development. PSC 3 Protection of Nature and Humans covers the synergetic benefits which protection of natural spaces and biodiversity and the reduction of environmental risks have for the protection of health and safety of the population. The study also revealed that integration of environmental, social, and economic aspects is often connected to conflicts between these dimensions. However, contributions which consider the economic situation of future generations or enhance social and human capital achieved considerable integration but showed no inclination toward such conflicts.  相似文献   

6.
杨学明 《生态环境》2000,9(4):311-315
大气CO  相似文献   

7.
Traditional means of assessing representativeness of conservation value in protected areas depend on measures of structural biodiversity. The effectiveness of priority conservation areas at representing critical natural capital (CNC) (i.e., an essential and renewable subset of natural capital) remains largely unknown. We analyzed the representativeness of CNC‐conservation priority areas in national nature reserves (i.e., nature reserves under jurisdiction of the central government with large spatial distribution across the provinces) in China with a new biophysical‐based composite indicator approach. With this approach, we integrated the net primary production of vegetation, topography, soil, and climate variables to map and rank terrestrial ecosystems capacities to generate CNC. National nature reserves accounted for 6.7% of CNC‐conservation priority areas across China. Considerable gaps (35.2%) existed between overall (or potential) CNC representativeness nationally and CNC representation in national reserves, and there was significant spatial heterogeneity of representativeness in CNC‐conservation priority areas at the regional and provincial levels. For example, the best and worst representations were, respectively, 13.0% and 1.6% regionally and 28.9% and 0.0% provincially. Policy in China is transitioning toward the goal of an ecologically sustainable civilization. We identified CNC‐conservation priority areas and conservation gaps and thus contribute to the policy goals of optimization of the national nature reserve network and the demarcation of areas critical to improving the representativeness and conservation of highly functioning areas of natural capital. Moreover, our method for assessing representation of CNC can be easily adapted to other large‐scale networks of conservation areas because few data are needed, and our model is relatively simple.  相似文献   

8.
SUMMARY

Studying the interactions among ecological factors and economic performance measured at the local scale is necessary to suggest policies able to mitigate natural resource depletion in complex ecosystems, like those in the Mediterranean region. The aim of this paper is to explore the relationship among natural resource depletion due to land degradation (LD) and some economic characteristics of local labour systems in Italy, a country where many areas, especially southern regions, are vulnerable. LD was estimated using an environmental sensitive area index, covering the national territory at a fine scale, which takes into account ecological factors such as climate, soil and vegetation. Economic indicators used here consider per capita income, land productivity, production and labour productivity by sector (agriculture, industry and services). A regression analysis was built-up at the LLS scale using an index change over time (1990–2000) as dependent variable and economic variables as predictors. A principal component analysis (PCA) was carried out to synthesise the outputs of the regression analysis. Results indicate a negative relationship among per capita income and LD over the whole study area. However, other variables showed a significant correlation with the dependent variable, highlighting the importance of local factors to increase land vulnerability. In order to clarify the contribution of economic factors to natural resource depletion it is necessary to drive integrate policies to combat LD in dry Mediterranean areas.  相似文献   

9.
10.
Abstract: One of the primary approaches to environmental conservation emphasizes economic development. This conservation‐and‐development approach often ignores how development affects sociocultural characteristics that may motivate environmental behaviors (actions that actively benefit or limit one's negative impacts on the environment). Evolutionary anthropologists espouse a theoretical perspective that supports the conservation‐and‐development approach. Others believe sociocultural factors are the foundation of environmental behavior and worry that development will erode the values and norms that may shape such behavior. My research assistants and I surveyed 170 individuals from eight villages in two communities in Bhutan to explore whether economic (wealth, market integration) or social (religious behaviors, environmental values, social capital) factors are better indicators of environmental behavior. I used multilevel modeling to analyze use of fuelwood, use of agricultural chemicals, and tree planting, and to determine whether social norms were associated with these behaviors. Although economic factors were more often associated with these behaviors than social factors, local conditions and control variables were the best indicators of behaviors. Furthermore, economic factors were not always associated with positive environmental outcomes. Instead, farmers attempted to make the best economic decisions given their circumstances rather than seeking to conserve resources. Although religion was not a strong predictor of any of the behaviors I examined, I found evidence that the understanding of Buddhist philosophy is growing, which suggests that social factors may play a more prominent role as Bhutan's development progresses. My results highlight the need for conservation planners to be aware of local conditions when planning and implementing policies aimed at motivating environmental behaviors and that economic and social motivations for conservation may not be mutually exclusive.  相似文献   

11.
Heavy metals are one of the hazardous contaminants in the total environment. The present study shows that the Sundarbans soil is contaminated with sludge and moderately contaminated with Cd and Co according to Contamination factor (CF), Enrichment factor (EF), Index of geo-accumulation (Igeo), and Ecological risk factor (ERF). The correlation, principle component analysis and factor analysis showed that Mn and Fe might have lithogenic origin whereas Cu, Pb, Co and Cd have anthropogenic inputs. The screening quick reference table (SQuiRT) shows that Cu and Cd may exert a possible toxic effect on the sediment dwelling biota. The phytoremediation study revealed that the endangered Heritiera fomes leaves can accumulate 80% of cadmium from the soil, which is highest based on this study as compared to other mangroves. The study also indicated that threatened date palm Phoenix paludosa leaves can accumulate 74% and 73% of Cu and Fe, respectively, from the soil. Now a day, there has been a spurt in mangrove plantations worldwide for the conservation of mangrove ecosystem using ecological engineering approaches. The present study is very much useful to choose a proper plant to decontaminate the soil from various heavy metal pollutants for effective management of mangrove wetlands.  相似文献   

12.
Abstract: Until recent decades, economic decision makers have largely ignored the nonmarket benefits provided by nature, resulting in unprecedented threats to ecological life‐support functions. The economic challenge today is to decide how much ecosystem structure can be converted to economic production and how much must be conserved to provide essential ecosystem services. Many economists and a growing number of life scientists hope to address this challenge by estimating the marginal value of environmental benefits and then using this information to make economic decisions. I assessed this approach first by examining the role and effectiveness of the price mechanism in a well‐functioning market economy, second by identifying the issues that prevent markets from pricing many ecological benefits, and third by focusing on problems inherent to valuing services generated by complex and poorly understood ecosystems subject to irreversible change. I then focus on critical natural capital (CNC), which generates benefits that are essential to human welfare and have few if any substitutes. When imminent ecological thresholds threaten CNC, conservation is essential and marginal valuation becomes inappropriate. Once conservation needs have been met, remaining ecosystem structure is potentially available for economic production. Demand for this available supply will determine prices. In other words, conservation needs should be price determining, not price determined. Conservation science must help identify CNC and the quantity and quality of ecosystem structure required to ensure its sustained provision.  相似文献   

13.
生草栽培对三种岭南水果种植系统的生态经济影响评价   总被引:4,自引:0,他引:4  
综合运用能值、经济与土壤生态学分析方法,以传统清耕模式为对照,定量研究了生草栽培对荔枝(Litchi chinensis Sonn)、龙眼(Dimocarpus longan Lour)和番荔枝(Annona squamosa Linn)三种岭南水果种植系统的生态经济影响。整合系统物质流、能量流和货币流,综合分析其自然资源基础、经济发展状况及可持续发展程度,并将土壤有机质的消耗纳入不可更新自然资源能值投入分析,为岭南水果业生草栽培与否提供科学依据。结果表明,生草栽培可以将荔枝和龙眼种植系统的能值可持续性从传统清耕模式的0.16和0.46分别提升到0.17和0.47;而使番荔枝种植系统的能值可持续性从传统清耕模式的0.59降至0.45。同时,生草栽培可提高荔枝和番荔枝种植系统的经济效益,而降低龙眼种植系统的经济效益。所有案例结果均表明,生草栽培可降低果园土壤有机质的消耗。  相似文献   

14.
Abstract: Recent literature on systematic conservation planning has focused strongly on economics. It is a necessary component of efficient conservation planning because the question is about effective resource allocation. Nevertheless, there is an increasing tendency toward economic factors overriding biological considerations. Focusing too narrowly on economic cost may lead us back toward solutions resembling those obtained by opportunistic choice of areas, the avoidance of which was the motivation for development of systematic approaches. Moreover, there are many overlooked difficulties in incorporating economic considerations reliably into conservation planning because available economic data and the free market are complex. For instance, economies based on free markets tend to be shortsighted, whereas biodiversity conservation aims far into the future. Although economic data are necessary, they should not be relied on too heavily or considered separately from other sociopolitical factors. We suggest focusing on development of more‐comprehensive ecological‐economic modeling, while not forgetting the importance of purely biological analyses that are needed as a point of reference for evaluating conservation outcomes.  相似文献   

15.
以重庆缙云山8种不同构建模式的水源涵养林及林地土壤为研究对象,用物种多样性指数(simpson指数、Shannon-Wiener指数)、均匀度指数(Pieiou指数)和物种丰富度指数(Margalef指数)以及用土壤容重、毛管孔隙度、非毛管孔隙度、pH值、有机质、全氮、全磷、全钾、速效氮、有效磷、速效钾和阳离子交换量12个指标表征土壤的物理性状和养分特征,分析了8种群落的植物多样性、土壤特征及二者的相互关系.结果表明:物种多样性以广东山胡椒(Lindera kwangtungensis)×杉木((7unninghamia anceolata)混交林最高.马尾松(Pinus massoniana)×广东山胡椒混交林次之,马尾松×柳杉(Cryptomeria fortunei Hooibrenk)混交林和毛竹(Phyllostachys pubescens)纯林最低.各模式林地土壤特征差异显著,以毛竹纯林土壤质量最差.在该地区针阔混交林对提高物种多样性和改良土壤作用显著,针叶林及纯林则较差.物种多样性指数与土壤特征因子的相关性分析表明,不同模式水源林群落植物多样性与土壤特征因子存在一定相关性,其中与土壤物理性状特征关系不显著,与养分特征关系显著.全N与全K与四个多样性指数呈显著或极显著的正相关,Shannon-Wiener指数、Simpson指数和有机质、阳离子交换量、速效P呈显著的正相关,特别是有机质和全N两因子与物种多样性关系最密切.  相似文献   

16.
四种岭南水果种植系统的能值、经济与土壤整合分析   总被引:2,自引:0,他引:2  
综合运用能值、经济与土壤生态学分析方法,定量研究了番石榴(Psidium guajava Linn)、黄皮(Clausena lansium Skeels)、枇杷(Eriobotrya japonica Lindl)、葡萄柚(Citrus paradisi Maef)4种岭南水果种植系统的物质流、能最流和货币流,综合分析其自然资源基础、经济发展状况及可持续发展程度,并将土壤有机质的消耗纳入不可更新自然资源能值投人分析,为岭南水果业的可持续发展提供科学依据.能值分析表明,4个水果种植系统的可持续发展能力依次为:葡萄柚(0.94)>枇杷(0.15)>番石榴(0.14)>黄皮(0.10).土壤有机质分布与变化分析表明,4种水果种植系统的土壤有机质消耗量依次为:葡萄柚>黄皮>枇杷>番石榴.经济分析表明,4个水果种植系统的经济效益依次为:葡萄柚>番石榴>枇杷>黄皮.综合分析表明,番石榴、黄皮、枇杷三个系统的水果生产效率有待进一步提高;葡萄柚种植系统的水果生产效率、可持续发展能力和经济效益较高,但其对土壤有机质的消耗强度在四个系统中是最高的,这一点在水土流失严重的丘陵地区显然是不容忽视的.同时,如何降低系统在市场交换中的交换性资产流失是四个系统共同面对的问题.  相似文献   

17.
保护性耕作对土壤养分及有机碳库的影响   总被引:6,自引:0,他引:6  
以稻草覆盖免耕方式稻田冬种马铃薯(Solanum tuberosum L.)为例,研究了保护性耕作对土壤养分以及有机碳库的影响.结果表明:保护性耕作能显著增加表层土层的养分含量,土壤氮素含量比传统耕作增加0.81%~7.24%,磷素含量增加14.95%~19.21%,钾素含量增加0.57%~15.40%,且全氮、全磷、全钾含量与传统耕作之间均达到了极显著差异水平,除碱解氮含量与传统耕作之间差异不显著外,速效磷与速效钾含量与传统耕作之间达到了显著差异水平与极显著差异水平;保护性耕作能增加土壤总有机碳与活性有机碳含量,提高土壤碳库管理指数,0~10 cm土层土壤的碳库管理指数分别比传统耕作高出9.10%、13.95%,10~20 cm土层则比传统耕作略低.因此保护性耕作能使土壤朝着有利于土壤质量提高的方向发展.两个保护性耕作处理:免耕稻草覆盖(8 cm)、免耕覆盖稻草(8 cm)后盖黑色地膜之间差异不大.  相似文献   

18.
This paper studies the production and attendant soil depletion choices of a risk-averse farmer in two related models. The first is a two-date model with uncertainty in both production and end-of-period land price. The second is a three-date model in which production and consumption choices are made in both periods, but there is uncertainty only in the second period. In both models, the paper identifies plausible conditions under which a higher level of initial farmer wealth and/or a lower level of production and land risk lead to a lower level of output and, as a result, a lower level of output-induced soil depletion.  相似文献   

19.
20.
鼎湖山南亚热带森林生态系统服务价值动态   总被引:1,自引:0,他引:1  
刘树华  李浩  陆宏芳 《生态环境》2011,(6):1042-1047
以鼎湖山3个南亚热带森林演替典型阶段生态系统为对象,采用我国《森林生态系统服务功能评估规范》(LY/T 1721—2008)标准化计算公式与服务价格,量化揭示南亚热带森林生态系统演替过程中生态系统服务功能价值动态。结果表明:随着演替的进行,南亚热带森林生态系统服务功能总价值不断增大;但各分项服务功能价值则表现出不同的动态规律与变化幅度,从而使得森林生态系统服务结构呈现非线性演化特征。在南亚热带森林生态系统演替的早期阶段,生态系统服务价值的最大组分是涵养水源的功能价值,而中、后期则是保育土壤。人工林营造可以有效增强区域生态系统的水源涵养能力,而保育演替中、后期森林则对于大气CO2收和土壤保育而言尤为重要。  相似文献   

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