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1.
《Chemistry and Ecology》2006,22(6):479-488
Tin concentrations were determined in surface and core sediments from three hot spots along the Alexandria coast, namely: Abu-Qir Bay, Eastern Harbour, and Western Harbour. The mean concentrations in surface sediment were 2.434, 3.212, and 5.572 μg/g dry weight for Abu-Qir Bay, Eastern Harbour, and Western Harbour, respectively. A sharp decrease in tin level in core sediments with depth was observed in almost all locations except for core 4 in Abu-Qir Bay and core 17 in the Eastern Harbour, where the sub-sample at the 5 cm level recorded the highest tin concentrations.  相似文献   
2.
New experimental data on biological productivity of plant communities in oligotrophic and mesotrophic bogs of the middle taiga subzone over the past five years are presented. The relationship between net primary production and the stock of live phytomass is estimated. The stock of necromass in oligotrophic bog ecosystems increases from west to east, while the stock of live phytomass and net primary production decrease.  相似文献   
3.
One feature of climate change is the trends to earlier spring onset in many north temperate areas of the world. The timing of spring flowering and leafing of perennial plants is largely controlled by temperature accumulation; both temperature and phenological records illustrate changes in recent decades. Phenology studies date back over a century, with extensive databases existing for western Canada. Earlier spring flowering has been noted for many woody plants, with larger trends seen for species that develop at spring's start. Implications for ecosystems of trends to earlier spring arrival include changes in plant species composition, changes in timing and distribution of pests and disease, and potentially disrupted ecological interactions. While Alberta has extensive phenology databases (for species, years, and geographic coverage) for recent decades, these data cannot provide continuous ground coverage. There is great potential for phenological data to provide ground validation for satellite imagery interpretation, especially as new remote sensors are becoming available. Phenological networks are experiencing a resurgence of interest in Canada (www.plantwatch.ca) and globally, and linking these ground-based observations with the view from space will greatly enhance our capacity to track the biotic response to climate changes.  相似文献   
4.
对英国可持续发展进程,国家及地方的可持续发展指标体系,以及地方21世纪议程编制的内容及特点进行了分析。  相似文献   
5.
This paper considers relationships between sustainability objectives, transport, spatial design of the built environment and rational use of energy. Conventional transport modelling, housing supply and energy assessment tools are drawn together to provide a common platform for appraisal of city-wide energy use by stationary and mobile sources. The paper outlines methodologies developed for the city of Belfast, Northern Ireland. The paper concludes by briefly reviewing the effect in terms of mobile and stationary energy consumption and travel behaviour of implementing sustainable policy measures in current and future years within the study area.  相似文献   
6.
豫西地区降水资源对旱地粮食作物产量的影响与对策   总被引:4,自引:0,他引:4  
本文论述降水资源是旱地粮食作物产量的重要影响因素,揭示了豫西地区主要粮食作物的需水规律和水分盈亏规律,提出运用地理风险决策、实行适水种植的宏观对策。  相似文献   
7.
实施西部开发战略应注意矿产资源开发、土地资源开发、水资源开发、森林资源开发、草地资源开发、农业资源开发、生物资源开发和旅游资源开发等活动的环境保护问题,本文就此问题提出建议。  相似文献   
8.
美国环境保护与环境技术产业发展的主要经验和启示   总被引:1,自引:1,他引:1  
随着经济和社会的发展,保护人类赖以生存的环境,走可持续发展之路,已成为世界范围内人们的共识,环境污染问题已日益成为人们关注的焦点。美国环境保护发展的历史与现状,揭示出一些促进环境保护和环境技术产业发展的经验,值得我们借鉴。  相似文献   
9.
西部大开发中水资源保护的战略意义   总被引:1,自引:1,他引:1  
陈国阶 《四川环境》2004,23(4):1-6,11
水是生命的源泉,水资源具有维持生命与健康功能,生态系统组成与演化功能,景观组合与美学功能:水能及其服务功能;水介质的传输与净化功能;社会生活与经济服务功能等。西部水资源具有发挥各种功能的区域条件。保护西部水资源的战略意义在于:(1)它是实施西部可持续发展战略的迫切需求;(2)西部是全国水资源富集区,对其保护具有全国战略意义;(3)水资源保护是西部生态建设的重要内容,是建成西部生态屏障的重要措施;(4)西部水资源是产业发展的支撑,对其保护对全国产业发展及其布局,有特殊功能和意义;(5)水资源昌西部农业命脉,保护水资源是西部农业持续发展的保证;(6)西部水资源保护具有跨流域的功能,有广泛的国际影响;(7)水资源保护是发展我国西部旅游产业的重要支撑。总之。西部大开发需要水资源的利用和保护,而水资源的保护和利用又是西部大开发的重要内容和成功的重要标志。  相似文献   
10.
This article develops a practical proposal for progress on sustainable development law. It examines the prospects for an international sustainable development law to provide a framework for more effective, coherent governance. Sustainable development law is briefly defined and an analytical framework is provided. Different degrees of integration between economic, social and environmental law are described. Certain principles of international law related to sustainable development are also highlighted. It is argued that these principles may serve to guide law‐makers and jurists where social, economic and environmental law and policy conflict or overlap. Continuing, underlying questions of sustainable development governance are addressed and its global frameworks analysed. The article also focuses on the 2002 World Summit on Sustainable Development, held in Johannesburg in August‐September 2002, and its specific mandate for the United Nations Commission on Sustainable Development (UNCSD) to take related legal developments into account. The article advances a proposal: that governments, economic, social and environmental intergovernmental organizations and other actors establish a ‘network of inquiry’ with members from relevant groups, including legal and academic organizations, and other expert groups, in order to follow, research, analyse and debate legal developments in a balanced way.  相似文献   
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