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731.
福建三沙湾海洋生态环境研究   总被引:4,自引:0,他引:4  
2000~2004年对三沙湾海洋生态环境进行了调查,分析了三沙湾海区多年来水质、水域养殖力(营养盐、叶绿素a和初级生产力)和浮游植物多样性的变化。调查后发现,养殖水域富营养化已经成为制约水产养殖业可持续发展的瓶颈,如何有效控制水体富营养化过程,降低海水养殖对环境产生的负面影响是一个非常现实的问题。因此,合理设置养殖容量、养殖方式、养殖种类,使退化的养殖海域得以修复,将对三沙湾海水养殖业的发展产生深远影响。  相似文献   
732.
Abstract

Rural–urban land conversion is an inevitable phenomenon in urbanization and industrialization. And the decision-making issue about this conversion is multi-objective because the social decision maker (the whole of central government and local authority) has to integrate the requirements of different interest groups (rural collective economic organizations, peasants, urban land users and the ones affected indirectly) and harmonize the sub-objects (economic, social and ecological outcomes) of this land allocation process. This paper established a multi-objective programming model for rural–urban land conversion decision-making and made some social welfare analysis correspondingly. Result shows that the general object of rural–urban land conversion decision-making is to reach the optimal level of social welfare in a certain state of resources allocation, while the preference of social decision makers and the value judgment of interest groups are two crucial factors which determine the realization of the rural–urban land conversion decision-making objects.  相似文献   
733.
ABSTRACT

As the space carrier of the construction of ecological civilization, land’s green and efficient utilization is an important guarantee for realizing national sustainable development. Based on traditional land evaluation, this paper scientifically defines the green land use, puts land as one of the production factors, and brings energy consumption, environmental pollution, etc. into the input-output system to measure the green land utilization efficiency of the urban construction land of Beijing-Tianjin-Hebei Urban Agglomeration from 2006 to 2016. The study shows that the overall efficiency variation of the urban agglomeration is related with the land and environment policies. Efficiency of 2016 is higher than that of 2006, and energy and environment are the principal factors affecting the green land use. The efficiency of each city is positively correlated with its economic development, negatively correlated with the construction land expansion. Efficiency gaps in different cities are expanding. There is positive correlation with overall weak space between cities, and the partial spatial agglomeration phenomenon appears. Therefore, the green land use efficiency could be improved by improving land utilization efficiency, coordinating economic growth of construction land utilization with environmental protection and taking feasible ways to transregional renovation of the stock ecological land utilization, etc.  相似文献   
734.
中国西部能源及矿业开发与环境保护协调发展研究   总被引:4,自引:0,他引:4  
中国西部地区自然环境脆弱且恶劣,但能源及矿产资源分布相对集中,能源及矿业开发已经成为其经济社会发展的支柱产业.本文力图从西部能源及矿业开发与环境保护协调发展、促进资源开发与生态保护的视角,综合辨析出西部地区能源及矿业开发引发的地质环境及生态环境恶化问题,主要包括土壤污染与土地破坏、水资源污染与短缺、矿区大气污染、噪声污染以及采矿诱发的各类地质灾害和生态环境破坏等.文章认为:西部地区矿产资源和能源开发等人为因素引发的地质环境及生态环境恶化问题日益突出,增强西部地区可持续发展能力,确保资源开发与环境保护的协调发展是西部地区提高能源资源保障能力的现实选择,也是转变发展方式、建设“两型”社会的必然要求.为此,本文对西部地区能矿资源开发与环境保护的协调发展提出了相关建议,主要包括:大力推行绿色发展,极开发绿色新能源;加强资源管理与污染控制,建立、健全矿产资源开发环境保护相关法律法规和体系,健全生态补偿机制;通过市场准入制度设立绿色门槛,继续整合小矿山;加强西部资源型城市与沿海地区的区域融合,减少资源开发的负外部性,破除“资源诅咒”;借鉴国际上“责任矿产开发倡议”,提高能源及矿产资源开发利益相关者的参与能力;统筹协调资源税费、地方发展基金,明确资源税的调节作用,健全利益分配机制,设立绿色发展基金;加强能矿资源开发全过程的第三方独立监管,在能源及矿产资源开发过程中实行有效透明的监管等.  相似文献   
735.
Urban and rural dual structure in Western China is obvious.The economic development of the central cities is relatively quick while that of the rural areas is lagging behind.The speeding up of urbanization contributes to the intensively uncoordinated development of urban and rural areas.Besides,the eco-fragile environment,shortage of available water resources,adverse geographic location,and relatively backward social economy restrict the development of urbanization in Western China.However,Western China also has the advantages of backwardness.This paper analyzes the present situation and development trend of urbanization in Western China.The results show that Western China has basically formed a development pattern with"industry promotes agriculture and urban leads to village".Therefore,combined with the present situation of Western China,this paper describes and analyzes the opportunities and challenges that may appear in the process of urbanization in Western China,puts forward the development pattern in which urban and rural areas can gain mutual support and co-development,and provides related recommendations.  相似文献   
736.
High population growth and continued economic development have caused serious environmental damage in the Asia Pacific region.However,the recent experience is that the pace of environmental degradation is faster in developing countries than in developed countries.To this end,the study seeks to assess the impact of population pressure on India’s environment,with particular reference to the degradation of natural endowments like land and water resources and the resultant environmental pollution in the six regions of India.The rapid economic growth and expansion of infrastructure development in recent decades have not come without serious environmental consequences particularly in the southern,northern,and western regions.But in the eastern,north-eastern,and central regions of the country,environmental damage has been mainly due to rapid population growth.  相似文献   
737.
WATCH     
Abstract

The development of everthing follows its own law, which does not change at people's own sweet will. Therefore, we must study the development of things so as to grasp the essence of things in their deep meanings, explore the direction of their development, and make them better serve the people. As a part of the thought of sustainable development, city environment art will be of active significance to the perfection of the thought and will also be the concrete embodiment of the synthetic index of economic development. Such a thesis, starting from the macroscopic angle, and relying on the leading thought of sustainable development, takes hold of the development trend of city environment art, and explores the various problems that have arisen in city environment in the process of city management by combining thoughts on city planning, so as to guide urban harmonious development theoretically. The present paper expounds on the views comprehensively and, through the synthetic analysis on city planning, city environment, art esthetics and the thought of sustainable development, makes a detailed analysis of the effects of the present rapid city development on city environment.  相似文献   
738.
Abstract

Although chemical control of pests increases crop production, it brings a lot of damage to environment and human health. There exist a number of alternative methods that are not so harmful to environment and human health. However, whether and how much in extent these technologies adopted are plausible depends on the comparison of benefit- cost between chemical control and the alternative control methods (such as Integrated Pest Management, IPM) and farmers' willingness-to-pay (WTP) for environment and human health. Using contingent valuation method (CVM), the author investigates farmers' WTP for environment and human health, recognizes the factors influencing WTP, and accordingly points out the importance of pest control technology extension and government regulation of pesticides.  相似文献   
739.
基于分形理论的江苏沿江城镇体系研究   总被引:7,自引:0,他引:7  
开放条件下,“全球 地方”作用深刻影响着区域城镇体系,沿江发达地区表现尤其典型。基于分形的相关理论和方法,以2006年为时空断面,对江苏沿江地区城镇体系的空间分布进行实证研究。结果表明:(1)区域城镇规模等级结构服从Zipf定律,首位城市南京在区域城市体系中的垄断性相对较强,但并非处于绝对垄断地位;(2)空间关联维数显示,沿江地区城镇体系的交通网络通达性优良,各城镇间联系紧密;(3)根据分维数和无标度区分析,三大城市群中,宁镇扬城市群分形发育最好,苏锡常次之,通泰城市群分形发育最差;(4)扬州、镇江、南京和苏州的城镇集聚程度较高,分形发育较为成熟;南通、泰州、无锡和常州的集聚程度均较低,分形结构不佳。扬州在区域城镇体系中分形发育最为完善,中心性最好,历史上形成的这种空间格局至今没有变化.  相似文献   
740.
近年来,随着我国经济的飞速发展、社会经济的转型,以及人们环境意识的提高,滨水区开发已成为我国城市开发建设的热点。城市滨水区景观规划设计研究对于合理、充分利用城市滨水区景观资源,塑造特色鲜明的城市形象,提高城市生态环境质量,促进城市滨水区开发有着重要意义。从复合生态系统理论的角度,在湘江滨水区景观资源调查、景观资源分类的基础上,运用灰色聚类法对湘江滨水区景观资源进行定量评价,提出景观资源优化思路,探讨滨水区景观规划设计的途径。认为现代城市大规模滨水区更新改造和开发大背景下的城市滨水区景观规划设计,应尊重城市地域性特点、文化内涵和风土人情,并与传统的滨水活动有机结合,保护和突出城市历史格局和风貌特色。  相似文献   
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