首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   189篇
  免费   26篇
  国内免费   40篇
  2023年   7篇
  2022年   10篇
  2021年   9篇
  2020年   7篇
  2019年   9篇
  2018年   11篇
  2017年   25篇
  2016年   14篇
  2015年   13篇
  2014年   11篇
  2013年   27篇
  2012年   7篇
  2011年   14篇
  2010年   10篇
  2009年   9篇
  2008年   10篇
  2007年   13篇
  2006年   10篇
  2005年   10篇
  2004年   3篇
  2003年   3篇
  2002年   3篇
  2001年   5篇
  2000年   1篇
  1999年   1篇
  1998年   5篇
  1995年   2篇
  1994年   1篇
  1988年   1篇
  1985年   4篇
排序方式: 共有255条查询结果,搜索用时 31 毫秒
31.
生态系统服务与自然资本价值评估   总被引:165,自引:9,他引:156  
张志强  徐中民  程国栋 《生态学报》2001,21(11):1918-1926
生态系统服务是生态系统提供的商品和服务,是人类生态和发展的物质基础和基本条件,是人类拥有的关键自然资本。概述了生态系统服务的内涵及类型,介绍了当前国内外有关生态系统服务及自然资本的价值理论、价值评估的各种方法及其类型;评述了研究的主要进展,存在的主要问题、难点和研究的主要趋向。认为生态系统服务及自然资本的价值评估研究是建立生态-环境-经济综合核算体系(可持续发展核算体系)的重要内容和关键环节,完善价值评估的理论与经济技术方法是生态系统服务价值评估研究亟待解决的问题。  相似文献   
32.
33.
This paper focuses on the analysis and evaluation of resilience anchored in an economic perspective. Resilience, as well as most of the benefits provided by ecosystems, is not priced on current markets. However, this does not mean that resilience is of no value for humans. On the contrary, the interest of using an economic perspective, and the respective scientific methodology, will be put forward in terms of resilience relevance for ecosystem functioning, and its impact on human welfare. The economic perspective is anchored in an anthropocentric analysis evaluating resilience in terms of provision of natural capital benefits. These in turn are interpreted as insurance against the risk of ecosystem malfunctioning and the consequent interruption of the provision of goods and services to humans. For this analysis, we make use of a conceptual framework that identifies and describes the different value components of resilience. Finally, we present an illustration that discusses the economic analysis of resilience benefits in the context of the Venice Lagoon.  相似文献   
34.
In this paper, the ecological integrity hierarchy framework (EIHF) and the natural capital index framework (NCI) are integrated as decision-making tools for evaluating the natural capital of Mexico. Two hierarchy-levels of ecological integrity indicators are used to estimate the quality and quantity of the natural capital, the amount of ecological degradation and ecological sustainability. After human transformation, the extent still considered as “natural” in the country is ∼67%; while the amount of human transformed areas is ∼33%, which gives a total estimate of NCI = 0.334; i.e., only ∼33.4% of the national capital remains available, while ∼33% is ecologically degraded. Furthermore, the critical natural capital; i.e., the legacy for future generations that remains in the country is only ∼12%. The total estimated value of the current natural capital in Mexico is ∼$457.1 billion/yr, which is ∼435 times greater than the national GDP ($1.051 billion in 2010). The cost of maintaining the degradation of the natural capital is ∼$144.6 billion/yr (∼138 times greater than national GDP in 2010). The potential value of the natural capital after restoration would be ∼$602 billion/yr. Valuing the natural capital can be helpful for strategic environmental evaluations and useful for spatial decision support systems that evaluate natural capital as a decision-making tool.  相似文献   
35.
生态资产核算与生态系统服务评估:概念交汇与重点方向   总被引:6,自引:0,他引:6  
刘焱序  傅伯杰  赵文武  王帅 《生态学报》2018,38(23):8267-8276
面向“山水林田湖草”统一管理的现实目标,对生态资产的准确刻画加深了资源管理者和使用者对生态系统服务的认识,是生态系统服务理论从学术研讨向决策实践过渡的重要桥梁。然而,当前的生态资产核算结果仍存在着较大的不确定性,使其决策支持作用受到质疑。基于对生态资产研究近今进展的总结,生态资产实际核算一般取自然资本与生态系统服务的交集分别作为存量和流量。如若将生态资产作为干部离任审计依据,则须把握先实物量后价值量的原则。在当前国际研究中,生态资产已经成为区域景观管理和农户生计决策的重要绩效评估与情景优选工具。完善生态系统服务评估模型、明晰生态系统服务供需关系、规范生态资产价值核算方法、提升生态资产决策支持能力4项内容应引起未来生态资产研究的重点关注。  相似文献   
36.
The investment in capital goods is a well‐known driver of economic activity, associated resource use, and environmental impact. In national accounting, gross fixed capital formation (GFCF) constitutes a substantial share of the total final demand of goods and services, both in terms of monetary turnover and embodied resources. In this article, we study the structure of GFCF and the environmental impacts associated with it on a global scale, and link it to measures of development. We find that the share of GFCF as part of the total carbon footprint (CF) varies more across countries than GFCF as a share of gross domestic product (GDP). Countries in early phases of development generally tend to invest in resource‐intensive assets, primarily infrastructure and machinery, whereas wealthier countries invest in less resource‐intensive assets, such as computers, software, and services. By performing a structural decomposition analysis, we assess the relative importance of investment structure and input‐output multipliers for the difference in carbon intensity of capital assets, and find that the structure of investments plays a larger role for less‐developed countries than for developed countries. We find a relative decoupling of the CF of GFCF from GDP, but we can neither confirm nor rule out the possibility of an absolute decoupling.  相似文献   
37.
38.
In group‐living species, the degree of relatedness among group members often governs the extent of reproductive sharing, cooperation and conflict within a group. Kinship among group members can be shaped by the presence and location of neighbouring groups, as these provide dispersal or mating opportunities that can dilute kinship among current group members. Here, we assessed how within‐group relatedness varies with the density and position of neighbouring social groups in Neolamprologus pulcher, a colonial and group‐living cichlid fish. We used restriction site‐associated DNA sequencing (RADseq) methods to generate thousands of polymorphic SNPs. Relative to microsatellite data, RADseq data provided much tighter confidence intervals around our relatedness estimates. These data allowed us to document novel patterns of relatedness in relation to colony‐level social structure. First, the density of neighbouring groups was negatively correlated with relatedness between subordinates and dominant females within a group, but no such patterns were observed between subordinates and dominant males. Second, subordinates at the colony edge were less related to dominant males in their group than subordinates in the colony centre, suggesting a shorter breeding tenure for dominant males at the colony edge. Finally, subordinates who were closely related to their same‐sex dominant were more likely to reproduce, supporting some restraint models of reproductive skew. Collectively, these results demonstrate that within‐group relatedness is influenced by the broader social context, and variation between groups in the degree of relatedness between dominants and subordinates can be explained by both patterns of reproductive sharing and the nature of the social landscape.  相似文献   
39.
40.
Modeling pollination ecosystem services requires a spatially explicit, process‐based approach because they depend on both the behavioral responses of pollinators to the amount and spatial arrangement of habitat and on the within‐ and between‐season dynamics of pollinator populations in response to land use. We describe a novel pollinator model predicting flower visitation rates by wild central‐place foragers (e.g., nesting bees) in spatially explicit landscapes. The model goes beyond existing approaches by: (1) integrating preferential use of more rewarding floral and nesting resources; (2) considering population growth over time; (3) allowing different dispersal distances for workers and reproductives; (4) providing visitation rates for use in crop pollination models. We use the model to estimate the effect of establishing grassy field margins offering nesting resources and a low quantity of flower resources, and/or late‐flowering flower strips offering no nesting resources but abundant flowers, on bumble bee populations and visitation rates to flowers in landscapes that differ in amounts of linear seminatural habitats and early mass‐flowering crops. Flower strips were three times more effective in increasing pollinator populations and visitation rates than field margins, and this effect increased over time. Late‐blooming flower strips increased early‐season visitation rates, but decreased visitation rates in other late‐season flowers. Increases in population size over time in response to flower strips and amounts of linear seminatural habitats reduced this apparent competition for pollinators. Our spatially explicit, process‐based model generates emergent patterns reflecting empirical observations, such that adding flower resources may have contrasting short‐ and long‐term effects due to apparent competition for pollinators and pollinator population size increase. It allows exploring these effects and comparing effect sizes in ways not possible with other existing models. Future applications include species comparisons, analysis of the sensitivity of predictions to life‐history traits, as well as large‐scale management intervention and policy assessment.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号