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101.
在当前中国经济快速增长和市场化改革逐步推进的过程中,始终面临着较为严重的土地违法问题;土地违法行为的主体不仅包括企事业单位和令人,更涉及各级地方政府以及农村集体组织.为深入了解经济增长与市场化改革对不同主体土地违法行为的影响,本文进行了初步的理论探讨,并运用全国层面的统计数据开展了相应的实证分析.结果表明,随着经济增长速度的加快,政府和企业的土地违法面积均显著增加;而土地市场化水平的提高则能有效减少土地违法的案件数.进一步地,经济增长和市场化改革对各级政府以及企事业单位、个人和农村集体组织土地违法行为的影响也存在一定的差异.本文的研究也指出,为有效控制土地违法行为的扩大,中国政府仍需采取转变经济增长方式、稳步推进市场化改革、引导企事业单位有序用地和不断完善土地督察制度等措施.  相似文献   
102.
西部生态环境脆弱而屏障作用显著.在新一轮西部大开发的背景下,对过去西部地区生态环境保护与管理政策进行回顾和总结,辨析其实施成效与存在的问题,并进一步提出相关政策建议,对今后西部国土开发和生态环境保护具有重要意义.本文通过对我国西部生态环境政策进行梳理和分析,发现:①西部地区的生态环境政策在不同阶段具有不同特征,改革开放以前(1949-1977年)主要是开发带动治理,改革开放-西部大开发之前(1978-1999年)逐渐由开发转变为以保护为主,西部大开发十年期间(2000-2010年)开始全面实施生态环境保护和建设;②在空间上,通过自然保护区设置、生态移民、财政转移支付和差别化的生态环境政策,在一定程度上促进了生态、社会、经济的协调发展;③在各项政策和工程实施下,西部生态环境退化趋势得到明显缓解,同时,农牧民的生活条件和经济收入得到较大提高,在生态环境治理、全社会参与、环保投资等方面探索出诸多成功经验;④生态环境政策还存在一些亟待解决的问题,如生态环境建设多以各个部门主导,缺乏统一规划和政策协调,有些政策缺乏充足的科学依据,生态补偿政策缺乏总体还需进一步完善,环境政策实施效果评估,反馈环节还较薄弱等.针对这些问题,本文最后提出建议.  相似文献   
103.
Abstract

Land-use change is an important aspect of global environment change. It is, in a sense, the direct result of human activities influencing our physical environment. This paper analyzed the land- use change in Northeast China during 1985–2000 based on Landsat TM images. It divides Northeast China into five land-use zones based on the dynamic degree model of land-use: woodland/grassland-arable land conversion zone, dry land-paddy field conversion zone; urban expansion zone, interlocked zone of farming and pasturing and reclamation and abandon zone. The findings include the obvious increase of cropland area, paddy field and dry land increased by 75 and 276 thousand hm2 respectively; urban areas expanded rapidly, areas of town and rural residence increased by 76.8 thousand hm2; areas of forests and grassland decreased sharply with the amounts of 1399 and 1521 thousand hm2 respectively; areas of water body and unused land increased by 148 and 514 thousand hm2 respectively. This paper also discusses the driving forces in each land-use dynamic zone and finds that some key biophysical factors affect conspicuously the conversion of different land-use types. The relation between land-use conversion and DEM, accumulated temperature (≤10°C) and precipitation was analyzed and represented. The land-use changes In Northeast China resulted from the changing macro social and economic factors and local physical elements. Rapid population growth and management changes can explain the shaping of woodland/grassland-cropland conversion zone. The conversion from dry land to paddy field in the dry land-paddy field conversion zone, apart from the change of physical elements promoting the expansion of paddy field, results from two reasons: one is that the implementation of market economy in China has given farmers the right to decide what and how they plant their crops, the other factor is originated partially from the change of the dietary habit along with the social and economic development. The conversion from paddy field to dry land is caused primarily by the shortfall of irrigation water, which in turn is caused by poor water allocation managed by local governments. The shaping of the reclamation and abandon zone is partially due to the lack of environment protection consciousness among pioneer settlers. The reason for the conversion from grassland to cropland is the relatively higher profits of farming than that of pasturing in the interlocked zone of farming and pasturing. In Northeast China, the rapid expansion of built-up areas results from two factors: the existence of a small number of towns and the huge potential for expansion of the existing towns and cities. The urban land expanded mainly in areas with a gentle topographic relief and low population density.  相似文献   
104.
Abstract

The Clean Development Mechanism, a flexibility mechanism contained in the Kyoto Protocol, offers China an important tool to attract investment in clean energy technology and processes into its electricity sector. The Chinese electricity sector places centrally in the country's economy and environment, being a significant contributor to the acid rain and air pollution problems that plague many of China's cities and regions, and therefore a focus of many related energy and environmental policies. China's electricity sector has also been the subject of a number of economic analyses that have showed that it contains the highest potential for clean energy investment through the Clean Development Mechanism of any economic sector in China. This mechanism, through the active participation from investors in more industrialized countries, can help alleviate the environmental problems attributable to electricity generation in China through advancing such technology as wind electricity generation, clean coal technology, high efficient natural gas electricity generation, or utilization of coal mine methane. In this context, the Clean Development Mechanism also compliments a range of environmental and energy policies which are strategizing to encourage the sustainable development of China's economy.  相似文献   
105.
Abstract

From angles of administrative law and private law, the article analyzes relations between environmental right for citizens and the right to use environmental resources owned by company and enterprise and points out three principles to balancing two relations: A principle of equal protection, a principle that general interest is superior to special interest as well as taking an account for special interest, in specific circumstances, for example, in the circumstance that clashes between environmental and economic interests can not be avoided, policy makers can put an emphasis on more important social interest according after considering weight of each interest. Finally, the article reaches a conclusion that China should establish system of environmental right for citizens from legislative and administrative levels so that a harmonious society can be constructed with guarantee.  相似文献   
106.
Abstract

Rapid urbanization in Beijing stimulates the urban land expansion and diminishes available agricultural land. Monofunctional agricultural land use can not meet the demand of the development of the multifunctional agriculture and urbanization any more, so multifunctional agricultural land use is going to be promoted in the city. This article proposes the evolvement of the land use change from 1992 to 2004 and discusses some evolvement views.  相似文献   
107.
Abstract

Nowadays the rising of opportunity cost of farm labor comes to the forefront of attention in China. In order to understand its impact on agricultural land-use structure, a theoretical framework of household economics is formulated drawn on Low’s model. Under the theoretical framework, the impact of the rising opportunity cost of on-farm on cropping structure is deduced in theory. And then, using statistic and survey data, taking mountain area of southern Ningxia as an example, the theoretical assumes are verified. The results show that the rise of opportunity cost of farm labor leads to less diversified cropping structure.  相似文献   
108.
Few other policy zones are as complex as the issue of climate change. If the more pessimistic projections of climate change doom are correct, then the failure to address the issue is likely to be catastrophic and irreversible. The Inter-governmental Panel on Climate Change has predicted the potential extinction of many species and that the existence of small-island and other vulnerable countries will be threatened if business-as-usual greenhouse gas emissions continue. Climate change is a transboundary problem and requires unprecedented levels of cooperation between states and serious and sustained responses from major emitters. However, the growing demand and consumption of natural resources for continued energy security and cornucopian economic growth have undermined the outcomes of international climate change negotiations. It is argued here that there is a strong connection between the major emitters’ positions at United Nations’ climate talks, their possessions, dependence and consumption of natural resources, and the continued undermining of international climate change policy for unsustainable growth. This paper assesses the resource politics of the US, China, India, Canada, Russia, and Saudi Arabia and their positions at climate talks to show the link between lack of climate change policy progress and the positions of these main players.  相似文献   
109.
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   
110.
Carbon dioxide (CO2) emission has drawn a great attention in recent years all over the world, and it plays a very important role in the process of global warming. The off-road equipment, which includes construction equipment, accounted for 7.5% emission of CO2. The objective of this article is to propose a groundwork for a methodology that can be used to estimate the total fuel use and CO2 emissions from construction equipment activities based on its productivity rate. Currently, there is not a methodology or technique for estimating productivity, fuel use and emissions at once. The multiple linear regression analysis has successfully modelled the productivity rate and good to be used as a benchmark for estimating fuel use and CO2 emissions from various types of construction equipment performing earthwork activities. The proposed methodology will help the contractor to estimate the total expected pollutant emissions for the project, which would be valuable information for a preliminary environmental assessment of the project. By using construction plans and specifications, the methodology and tool presented in this research can be used to estimate cost, fuel use and emissions from commercial, residential, industrial or heavy highway. By the proposed approach, it is possible to develop new fuel use and emissions inventories for construction industry in general.  相似文献   
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