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461.
The extent of wetland in New Zealand has decreased by approximately 90% since European settlement began in 1840. Remaining
wetlands continue to be threatened by drainage, weeds, and pest invasion. This article presents a rapid method for broad-scale
mapping and prioritising palustrine and estuarine wetlands for conservation. Classes of wetland (lacustrine, estuarine, riverine,
marine, and palustrine) were mapped using Landsat ETM+ imagery and centre-points of palustrine and estuarine sites as ancillary
data. The results shown are for the Manawatu–Wanganui region, which was found to have 3060 ha of palustrine and 250 ha of
estuarine wetlands. To set conservation priorities, landscape indicators were computed from a land-cover map and a digital
terrain model. Four global indicators were used (representativeness, area, surrounding naturalness, and connectivity), and
each was assigned a value to score wetland sites in the region. The final score is an additive function that weights the relative
importance of each indicator (i.e., multicriteria decision analysis). The whole process of mapping and ranking wetlands in
the Manawatu–Wanganui region took only 6 weeks. The rapid methodology means that consistent wetland inventories and ranking
can now actually be produced at reasonable cost, and conservation resources may therefore be better targeted. With complete
inventories and priority lists of wetlands, managers will be able to plan for conservation without having to wait for the
collection of detailed biologic information, which may now also be prioritised. 相似文献
462.
463.
To help stem the continuing decline of biodiversity, effective transfer of technology from resource‐rich to biodiversity‐rich countries is required. Biodiversity technology as defined by the Convention on Biological Diversity (CBD) is a complex term, encompassing a wide variety of activities and interest groups. As yet, there is no robust framework by which to monitor the extent to which technology transfer might benefit biodiversity. We devised a definition of biodiversity technology and a framework for the monitoring of technology transfer between CBD signatories. Biodiversity technology within the scope of the CBD encompasses hard and soft technologies that are relevant to the conservation and sustainable use of biodiversity, or make use of genetic resources, and that relate to all aspects of the CBD, with a particular focus on technology transfer from resource‐rich to biodiversity‐rich countries. Our proposed framework introduces technology transfer as a response indicator: technology transfer is increased to stem pressures on biodiversity. We suggest an initial approach of tracking technology flow between countries; charting this flow is likely to be a one‐to‐many relationship (i.e., the flow of a specific technology from one country to multiple countries). Future developments should then focus on integrating biodiversity technology transfer into the current pressure‐state‐response indicator framework favored by the CBD (i.e., measuring the influence of technology transfer on changes in state and pressure variables). Structured national reporting is important to obtaining metrics relevant to technology and knowledge transfer. Interim measures, that can be used to assess biodiversity technology or knowledge status while more in‐depth indicators are being developed, include the number of species inventories, threatened species lists, or national red lists; databases on publications and project funding may provide measures of international cooperation. Such a pragmatic approach, followed by rigorous testing of specific technology transfer metrics submitted by CBD signatories in a standardized manner may in turn improve the focus of future targets on technology transfer for biodiversity conservation. 相似文献
464.
对我国生态市(县)建设的几点思考 总被引:1,自引:0,他引:1
李克国 《中国环境管理干部学院学报》2011,(5):25-29
通过对我国生态市(县)的建设现状、建设指标的修订情况及建设意义进行深入分析,从组织领导、建设规划、建设机制等方面提出了建设生态市(县)的可行性措施。 相似文献
465.
M.M. JiangB. Chen 《Ecological modelling》2011,222(13):2149-2165
This paper presented a thermodynamic synthesis that involved resource accounting, evaluation and modeling of urban ecosystems based on embodied cosmic exergy (EcE), which redefined embodied exergy with the cosmic microwave background radiation (CMBR) as the reference for solar exergy. In a case study of the Beijing urban ecosystem, the major resources supporting the urban ecosystem, both from free natural resources and from the economy, were accounted for, analyzed and evaluated in the same units, Cosmic Joules (Jc). These indicators revealed the current performance of the Beijing urban ecosystem by considering five aspects of the system: EcE sources, EcE intensity, EcE welfare, environmental impacts and economic efficiency. Moreover, through the combination of the EcE synthesis with a systems dynamics, this research constructed an embodied cosmic exergy-based urban system model (EESM) using Beijing as an example of urban development. The results show that the 10 years from 2010 to 2020 will be very critical for the sustainable development of Beijing because many key factors, such as water resources, wastes and urban assets, might be confronted with great changes during this period. These changes will inevitably transform the urban system not only in its external circumstances but also in its inner structure and may lead to serious consequences. Of all the necessary resources, the most sensitive factor is water supply. 相似文献
466.
中国生态修复成效评估方法研究 总被引:2,自引:0,他引:2
目前已有很多的生境、自然资源以及水质修复措施被开发出来,而生态修复后的监测、成效评估等研究内容相对较少。在分析国内外生态修复概念的研究进展基础上,从生态修复目标、评价指标体系、评估方法以及数据获取方法等4个方面对生态修复后的效果评估的当前研究进行了分析,探讨了国内现有研究中存在的问题,指出应加强生态修复成效评估的理论和方法研究,并对今后中国生态修复成效评估研究进行了展望。 相似文献
467.
五溴联苯醚是一种典型的持久性有机污染物,其广泛使用对环境造成的污染以及对生物产生的毒性越来越严重,因此研究五溴联苯醚的修复技术具有重要意义.结合当前国内外的研究进展,综述了污染环境中五溴联苯醚的多种修复方法,包括物理修复、化学修复及生物修复等,并介绍了修复技术的机理及影响因素.今后发展的主要方向是寻求多种方法协同作用,以达到快速、彻底的对五溴联苯醚进行降解的效果. 相似文献
468.
深圳市一次典型春季臭氧污染事件成因研究 总被引:1,自引:0,他引:1
以往珠三角地区臭氧污染普遍发生在秋季,但近年来春季臭氧污染事件不断发生,并且污染出现时间愈发提前.本研究聚焦于深圳市2022年春季(2月26日)一次臭氧污染过程,系统性地分析了此次臭氧污染过程的主要成因与关键驱动因素.结果表明,在春季臭氧污染的形成过程中,气象条件扮演着重要角色,在高压天气系统影响下的强太阳辐射、高温、低湿和低风速是导致此次臭氧污染的重要因素.通过臭氧的垂直观测数据分析发现,夜间残留层中的高浓度臭氧能够在上午时段混入边界层内,加速地面臭氧浓度累积.此外,通过臭氧前体物浓度的变化特征分析发现,在污染日的下午时段出现臭氧及其前体物浓度的快速升高,推测为上风向区域的外部输送贡献加强,这也是导致此次春季臭氧污染发生的重要原因.敏感性分析表明,污染日的臭氧生成主要受VOCs控制,但在污染加剧时受到NOx控制,因此,对春季臭氧污染的 防控需要从区域角度开展VOCs和NOx的协同减排与治理. 相似文献
469.
Zhen Lin Zhou Hailin & Xie Gaodi Institute of Geographic Sciences Natural Resources Research Chinese Academy of Sciences Beijing China The Administrative Center for China''''s Agenda Beijing China 《中国人口.资源与环境(英文版)》2005,3(3)
1 INTRODUCTION Growing pressure on the land of North China Plain (NCP - a food bowl of the country, has made many of th traditional farming practices increasingly difficult to sustain such as manuring, composting, mulching, legume-based rotations, field levelling and fertilizing with mud from rivers and canals. The pressure on the farmlands has also led to a decrease in farm sizes and shortened fallow periods To cope with this pressure on the land and to maintain its fertility, farmers … 相似文献
470.
Shim Yoffe Aaron T. Wolf Mark Giordano 《Journal of the American Water Resources Association》2003,39(5):1109-1126
ABSTRACT: In this paper we seek to identify historical indicators of international freshwater conflict and cooperation and to create a framework to identify and evaluate international river basins at potential risk for future conflict. We derived biophysical, socioeco‐nomic, and geopolitical variables at multiple spatial and temporal scales from GIS datasets of international basins and associated countries, and we tested these variables against a database of historical incidents of international water related cooperation and conflict from 1948 to 1999. International relations over freshwater resources were overwhelmingly cooperative and covered a wide range of issues, including water quantity, water quality, joint management, and hydropower. Conflictive relations tended to center on quantity and infrastructure. No single indicator—including climate, water stress, government type, and dependence on water for agriculture or energy—explained conflict/cooperation over water. Even indicators showing a significant correlation with water conflict, such as high population density, low per capita GDP, and overall unfriendly international relations, explained only a small percentage of data variability. The most promising sets of indicators for water conflict were those associated with rapid or extreme physical or institutional change within a basin (e.g., large dams or internationalization of a basin) and the key role of institutional mechanisms, such as freshwater treaties, in mitigating such conflict. 相似文献