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961.
欧盟是世界环境保护与可持续发展的主要倡导者和推动者,在环境地质科学研究方面积累了大量先进的理念、经验和做法。在论述欧盟环境管理基本理念的基础上,从填图、监测、机理研究3个方面分析了欧盟地区环境地质调查和科学研究工作现状,概括总结了其在环境地质领域的科学发展战略重点,梳理出各成员国地质调查机构从传统地质调查工作向服务生态管理的现代地质调查工作转变的发展路线。在此基础上,提出了对中国环境地质调查和研究工作的启示:加强地质环境生态服务功能评估;加强统一的地质环境监测体系建设;开展地球关键带三维地质调查与监测;加强地质环境事件快速响应基础研究。 相似文献
962.
963.
Alpine Ecosystems of Northwest Yunnan, China: an Initial Assessment for Conservation 总被引:1,自引:1,他引:0
Ruth Sherman Renee Mullen LI Haomin FANG Zhendong WANG Yi 《山地科学学报》2007,4(3):181-192
Implementing conservation actions on-the-ground is not a straightforward process,especially when faced with high scientific uncertainty due to limited available information. This is especially acute in regions of the world that harbor many unique species that have not been well studied,such as the alpine zone of the Hengduan Mountains of Northwest Yunnan (NWY),a global biodiversity hotspot and site of The Nature Conservancy’s Yunnan Great Rivers Project. We conducted a quantitative,but rapid regional-level assessment of the alpine flora across NWY to provide a broad-based understanding of local and regional patterns of the alpine flora,the first large-scale analysis of alpine biodiversity patterns in this region. Multivariate analyses were used to classify the major plant community types and link community patterns to habitat variables. Our analysis indicated that most species had small distributions and/or small population sizes. Strong patterns emerged with higher diversity in the more northern mountains,but beta diversity was high,averaging only 10% among sites. The ordinations indicated that elevation and geographic location were the dominant environ-mental gradients underlying the differences in the species composition among communities. The high beta diversity across the alpine of these mountains implies that conservation strategies ultimately will require the protection of large numbers of species over a large geographical area. However,prioritiza-tion should be given to areas where potential payoffs are greatest. Sites with high species richness also have a greater number of endemic species,and,by focusing efforts on these sites,conservation investments would be maximized by protecting the greatest number of unique species. 相似文献
964.
China's policy on ecological compensation (eco-compensation) in watershed eco-systems is of economic,social and environmental significance for China's ecological gov-ernance and protection of natural areas.It involves balancing the interests of regional stakeholders,coordinating the development of regional environments and establishing effec-tive cooperation models,making it a classic topic for geographical research.This study in-troduces the concept of institutional "stickiness" to the theory of politics of scale to analyze the features and mechanisms of the game behavior of government entities in the process of im-plementing watershed eco-compensation in the Xin'an River Basin.Our results show the following:government entities at various levels,including the central,provincial and municipal governments,experienced the three stages of game strategy of competition,cooperation and"coopetition";building a government community of shared interests can promote watershed eco-compensation,and "appropriate intervention" by the central govemment is key to achieving inter-provincial watershed eco-compensation;there was clear institutional stickiness during the transition from a "vertical" model of watershed eco-compensation to a "vertical-horizontal"model,with government entities using policy innovations and social participation to limit and reduce stickiness so as to reshape the watershed eco-compensation system;scalar jumping is the core mechanism that promoted eco-compensation in the study basin,and government entities shaped the discourse on watershed eco-compensation by redistributing powers and capital and creating informal constraints,which promoted the transformation of eco-compensation from a "strong state-weak society" structural model,to a "strong state-strong society" model in the Xin'an River Basin.These results can provide theoretical support for the construction of inter-regional watershed eco-compensation mechanisms,pro-vide a scientific basis for the rational evaluation and guidance of watershed eco-compensation practices,and promote the coordinated and sustainable socioeconomic development of watersheds. 相似文献
965.
TAN Fang-Lin 《湿地科学》2007,5(2):105-110
Spartina is a kind of very important and invasive grass. In its native range, it is very important for erosion control, fish, wildlife, and estuary reclamation. Therefore, it was introduced to many countries. Since 1963, it was introduced to China. Up to now, it was intentionally or accidentally planted nearly all estuaries in the east coast of China and the area was estimated over 0.1×106 hm2. As other introduced plants, Spartina grows very vigorously in China, and this caused many environmental and economical problems. So, it is an emergency to develop a Spartina control strategy of China. In the paper, the history of Spartina introduction in China was reviewed, and several methods which were probably feasible for China to control Spartina were introduced, including physical/mechanical (such as mowing, digging, and dredging), chemical, and biological methods. Before taking any measurments to control Spartina, 2 things should be done. The first was to develop a plan and make an inventory; the second was to select a feasible method according to local climatic, economic, social, and ecological conditions. It was suggested that it would be very important to assess the possible effect of control methods on the environment in order to prevent from causing other environmental problems. 相似文献
966.
967.
968.
中国东北红河国家级自然保护区湿地植被空间格局与环境梯度关系(英文) 总被引:1,自引:0,他引:1
Quantifying correlation between the spatial patterns of natural wetland plants and environmental gradient gives better understanding of wetland habitats, which is the fundamental for the strategy making on the protection and restoration of natural wetlands. In this study, the spatial patterns of wetland plants and the environmental gradient of wetland habitats were assessed in the Honghe National Nature Reserve (HNNR) in Northeast China, a wetland of international importance on the Ramsar list. Biophysical parameters’ values of wetland plants were obtained by field sampling methods, and wetland mapping at the community scale was completed using remote sensing techniques. Digital delineation of the surface water system, hydrological zoning and wetness index were produced by spatial analysis methods in Geographic Information System. An ecological ordination method and two clustering methods were used to quantify the relationship between the spatial distribution patterns of wetland plants and the corresponding environmental gradients. Such quantitative analyses also present the specific diversity of different types of wetland plants based on the environmental attributes of their habitats. With the support from modern geo-information techniques, the experimental results indicate how four ecotypes of wetland plants spatially transit from forest swamp, shrub wetland and meadow into marsh wetland with increasing wetness index and water table. And they also show how wetland spatial distribution patterns are controlled by an environmental gradient of wetness. Another key finding of this research work is that our results present the exact fundamental differences between marsh and non-marsh plants of 11 wetland plant communities within the core study area. Hence, this case study gives a good sample for better understanding of the complex correlation between the spatial patterns of wetland plants and their environmental attributes using advanced digital analysis methods. It is also useful to show how to integrate geoinformatic techniques with statistical analysis methods based on the field data base. 相似文献
969.
城市公共健康风险是当代城市研究的一个重要主题,在中国人文地理学界尚未得到充分关注。国内既有研究主要集中在两个维度——健康城市建设和城市风险治理,然而这些研究受到城市/自然二元论的影响。自20世纪90年代以来,城市政治生态学在西方人文地理学界迅速崛起,提出了以社会关系为核心的城市新陈代谢理论,在空间和联系两个层面将社会与自然,人类行为体与非人类行为体联系起来,实现了对二元论的超越。基于这一理论,本文从空间和联系层面对城市公共健康风险的具体形式进行分析,指出在空间层面上,存在空间流转和重叠的公共健康风险和空间生产和再生产活动的公共健康风险;就联系层面而言,存在“新陈代谢断裂”的公共健康风险和公众认知的公共健康风险。 相似文献
970.
资源型城市土地利用变化与湿地生态安全响应--以黑龙江省大庆市为例 总被引:10,自引:1,他引:10
黑龙江省大庆市作为典型的资源型城市(以石油资源、草场资源和耕地资源发展起来),是人地关系作用最强烈的区域之一,也是土地利用发生急剧变化且具有特色的区域.揭示本区域土地利用的时空变化特征和变化规律,探讨土地利用变化引发的生态安全问题,对于资源型城市生态环境改善,产业结构调整及实现资源型城市可持续发展尤为重要.为此,本研究基于大庆市1978、1988、1992、1996和2001年5个时段的MSS和TM影像,获取20a来不同时期的土地利用信息.以GIS技术为数据集成分析平台,计算湿地景观格局指数和各湿地景观类型的时空转移过程,以期从景观格局的角度定量刻画区域湿地景观过程对土地利用变化的响应和由此产生的湿地生态安全威胁.结果表明,区域内耕地不断增加,建设用地的扩大,以及湿地盐碱化和草甸化过程,是湿地减少的重要原因之一;土地利用造成的湿地景观分割、景观破碎和景观迅速减少,对生物多样性安全、水资源安全和人类健康安全等产生威胁;因而,应根据人类与自然共生原理,对不同湿地进行景观生态的分析、评价、规划和设计,逐步恢复原有的自然湿地景观,使其发挥多种湿地功能. 相似文献