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11.
加拿大海洋环境管理立法状况   总被引:4,自引:0,他引:4  
加拿大政府历来重视保护、恢复和改善海洋自然生态系统,特别是重视海洋环境的保护、管理和立法。本文较系统地介绍了加拿大的海洋环境管理的部门与职责、海洋环境立法的状况以及所采取的主要措施等。  相似文献   
12.
Human beings have had a tremendous impact on natural ecosystems and are now the principal power to change the biosphere.It is logical that we should pay close attention to the interaction between human systems and environ-mental systems.Taking Minqin bsin ,Gansu Province,as a case,this paper focuses on the evolution of regional physic-cal environments and the cultural systems by which people maintain their relationships with those environments.This pa-per presents the conceptural framework for the man-land system.Expecting to accelerate the regional sustainable develop-ment,it also analyses the evolutionary mechanism of regional man-land system.On the basis of reviewing and analyzing the evolution of man-land system in Minqin basin,the paper also brings forward an adujusting mode for the studied area, which consists of three aspects:to build up a concept that economic growth must harmonize with environmental qualityˊs and land productivityˊs improvement;to make a whole planning and management in the drainage area;and to push for-ward the technique of water-saving irrigation and establish water-saving agricultural system. Itˊs meaningful for resource exploitation and sustainable development of Chinese northwestern arid area,which is represented by Minqin basin,by under-standing what great changes the basin has experienced is experiencing at the global background,and studying its time standing what great changes the basin has experienced and is experiencing at the global background,and studying its time order and territorial structure ,the systemˊs character and law of evolution,trend and the regulating ways to improve man-land relationship.  相似文献   
13.
作者根据多年工作实践,阐述生态环境规划在国土规划中的重要地位和作用,以及生态环境规划的内容、程序、方法问题。  相似文献   
14.
全球土地利用与覆盖变化(LUCC)研究及其进展   总被引:1,自引:0,他引:1  
人类最早的土地利用方式是向自然生态系统直接索取,如采集、狩猎等。定居生活的开始标志着人类历史上土地利用方式的第一次重大转变。这一转变带来了以砍伐森林、开垦耕地为主要表现的土地利用变化,其目的是缓解人口增长所带来的粮食需求压力。这种变化过程延续了上万年,  相似文献   
15.
越来越强烈地利用地下水的同时,伴随着对自然生态系统的技术成因负栽的加强,是必须最优化利用适于不同活动方向区域并计及自然资源,特别是地下水保藏的条件。  相似文献   
16.
Net primary productivity (NPP) is the structure and function of the ecosystem. NPP can most important index that represents the be simulated by dynamic global vegetation models (DGVM), which are designed to represent vegetation dynamics relative to environ- mental change. This study simulated the NPP of China's ecosystems based on the DGVM Integrated Biosphere Simulator (IBIS) with data on climate, soil, and topography. The appli- cability of IBIS in the NPP simulation of China's terrestrial ecosystems was verified first. Comparison with other relevant studies indicates that the range and mean value of simula- tions are generally within the limits of observations; the overall pattern and total annual NPP are close to the simulations conducted with other models. The simulations are also close to the NPP estimations based on remote sensing. Validation proved that IBIS can be utilized in the large-scale simulation of NPP in China's natural ecosystem. We then simulated NPP with climate change data from 1961 to 2005, when warming was particularly striking. The following are the results of the simulation. (1) Total NPP varied from 3.61 GtC/yr to 4.24 GtC/yr in the past 45 years and exhibited minimal significant linear increase or decrease. (2) Regional differences in the increase or decrease in NPP were large but exhibited an insignificant overall linear trend. NPP declined in most parts of eastern and central China, especially in the Loess Plateau. (3) Similar to the fluctuation law of annual NPP, seasonal NPP also displayed an insignificant increase or decrease; the trend line was within the general level. (4) The re- gional differences in seasonal NPP changes were large. NPP declined in spring, summer, and autumn in the Loess Plateau but increased in most parts of the Tibetan Plateau.  相似文献   
17.
王国起 《地球》2013,(9):30-33
正极端天气的背后,其实是温室效应导致的全球变暖。全球变暖的后果,会使全球降水量重新分配、冰川和冻土消融、海平面上升等,既危害自然生态系统的平衡,更威胁人类的食物供应和居住环境。现在多数人普遍认为,是全球变暖导致越来越频繁的极端天气。全球气候变暖是一种"自然现象"。人们焚烧化石矿物或砍伐森林并将其  相似文献   
18.
Climate change has major impacts directly on the natural ecosystem and human society, of which the cryosphere is most easily affected be-cause of its frangibility and sensitivity. Similarly, cryosphere change has numerous impacts on the natural ecosystem and human society, which may resemble an indirect influence of climate change. These two types of impacts, in shared fields, are distinguished in space and time by effective mechanisms and processes. Climate change has positive and negative impacts on some systems, which may be adjusted by cryosphere change. These indirect and direct impacts may be distinguished, and then correct policies and measures can be made against these changes.  相似文献   
19.
《南方国土资源》2013,(4):16-17
十八大报告提出,加大自然生态系统和环境保护力度,国土资源管理部门该如何发挥行业优势,确保这项战略的顺利实施?党的十八大报告提出,加大自然生态系统和环境保护力度,对国土资源管理工作提出了新的更高要求。加大自然生态系统和环境保护的力度涵盖了怎样的具体内容?学习党的十八大报告,结合行业工作,我们深刻地认识到,要  相似文献   
20.
《南方国土资源》2013,(2):21-24
推进防灾减灾体系建设,特别是加大地质灾害防治力度,保护人民群众生命财产安全,是国土资源部门义不容辞的责任。党的十八大报告提出,要加大自然生态系统和环境保护力度。实施重大生态修复工程,增强生态产品生产能力,推进荒漠化、石漠化、水土流失综合治理。加快水利建设,加强防灾减灾体系建设。坚持预防为主、综合治理,解决损害群众健康的突出环境问题。  相似文献   
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