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831.
大气污染物排放及影响因素研究,是引导区域减排实现可持续发展的重要依据。利用Tapio脱钩模型测度了1996~2013年长江经济带11个省区工业经济增长与工业废气、工业二氧化硫、工业烟粉尘3个指标之间的脱钩程度,并利用LMDI分解模型对大气污染物排放变化特征进行了影响因素分解。结果表明:(1)长江经济带11个省(市)的工业废气排放量呈持续上升的趋势,且工业废气排放量的“热”点区域主要集中在东部地区,工业二氧化硫和烟粉尘两种大气污染物排放量总体呈现“先增加后减少”的趋势,状况有所改善。(2)长江经济带工业废气排放整体经历了从扩张性负脱钩到相对脱钩发展的趋势,表明经济发展的同时带来工业废气排放的污染同步增长。经济发展效应和能源效率效应是促使工业废气排放的主要因素。(3)长江经济带的工业二氧化硫和烟粉尘排放整体上经历了从相对脱钩向绝对脱钩发展的趋势,经济发展均是造成各地区两种污染物排放量增加的主要原因,技术效应和能源效率是各地区两种污染物减排的重要影响因素。未来,在大气污染物的减排控制过程中,需加强产业结构、能源结构的调整,也需坚定依靠技术进步推动能源使用效率的提高,并且注重各省市间的减排差异和防范污染产业的区域转移。关键词: 长江经济带;经济增长;大气环境;脱钩分析模型;LMDI分解模型  相似文献   
832.
基于长江经济带11个省市2005~2015年土地变更调查数据,从土地开发均衡度和土地开发限度两方面对该地区的土地开发强度进行综合评价。研究表明:(1)长江经济带各省市土地均衡度呈现两极分化,东部和西部地区土地开发失衡,中部地区土地开发相对均衡;(2)长江经济带整体土地开发限度为5.58%,11省市均超过或临近极限值,未来需建立集约型土地开发模式;(3)长江经济带不同地区的土地开发强度差异显著,呈现出下游高上游低,东部高集聚的空间格局。因此,应参考各省市土地开发限度对规划进行修编;增强土地供给能力,为建设用地紧张地区挖掘新的开发潜力;建立跨区域的土地开发体制等,通过完善政策法规促进土地的合理开发利用。  相似文献   
833.
Land reclamation significantly affects the ecological and environmental conditions of mining areas. However, quantifying the exact effects is difficult because of the lack of reliable data. The estimation of eco-environment benefit contributes to clarify the ecological and environmental changes caused by land reclamation and to provide useful information for policy-makers concerned with sustainable development. The aim of this study is to investigate variations in eco-environment benefit in response to land use changes during land reclamation. The West dump, one of the earliest regions to implement ecological restoration in Liaoning Province, is selected as the study area. The widely used methods for eco-environment benefits based on the land use change were proposed and applied to the West dump in 2004, 2009, and 2014. The total eco-environment benefits in study areas were 0.98 million dollars in 2004, 1.39 million dollars in 2009, and 1.43 million dollars in 2014, with an increase of 0.41 million dollars from 2004 to 2009 mainly because of the increasing areas of artificial woodland and reclaimed cropland. The combined eco-environment benefits of artificial woodland, improved grassland, and reclaimed cropland were over 90% of the total benefits. Soil formation and protection, biodiversity protection, and gas regulation were the top three functions with high eco-environment benefits, contributing about half of the total eco-environment benefits. The results suggest that future studies estimating eco-environment benefits should pay more attention to ecosystems in fragile ecological regions where various human interferences happen frequently. All of the abovementioned results made the techniques of estimation of the eco-environment benefit of land reclamation are more meaningful in guiding the future exploitation and reclamation of mining areas.  相似文献   
834.
Economic costs, water quantity/quality benefits, and cost effectiveness of agricultural best management practices (BMPs) at a watershed scale are increasingly examined using integrated economic‐hydrologic models. However, these models are typically complex and not user‐friendly for examining the effects of various BMP scenarios. In this study, an open source geographic information system (GIS)‐based decision support system (DSS), named the watershed evaluation of BMPs (WEBs), was developed for creating BMP scenarios and simulating economic costs and water quantity/quality benefits at farm field, subbasin, and watershed scales. This DSS or WEBs interface integrated a farm economic model, the Soil and Water Assessment Tool (SWAT), and an optimization model within Whitebox Geospatial Analysis Tools (GAT), an open source GIS software. The DSS was applied to the 14.3‐km2 Gully Creek watershed, a coastal watershed in southern Ontario, Canada that drains directly into Lake Huron. BMPs that were evaluated included conservation tillage, nutrient management, cover crop, and water and sediment control basins. In addition to assessing economic costs, water quantity/quality benefits, and cost effectiveness of BMPs, the DSS can be also used to examine prioritized BMP types/locations and corresponding economic and water quantity/quality tradeoffs in the study watershed based on environmental targets or budget constraints. Further developments of the DSS including interface transfer to other watersheds are also discussed. Editor's note : This paper is part of the featured series on SWAT Applications for Emerging Hydrologic and Water Quality Challenges. See the February 2017 issue for the introduction and background to the series.  相似文献   
835.
In places like Canada, fast-paced wind turbine development combined with policy that limits local decision-making power has resulted in strong opposition to specific projects. Some studies suggest that anti-wind sentiment is tied to inadequate financial benefits – especially sharing at the local level. Thus, ideas of distributive economic justice have received traction, particularly in the form of praise for community-based development models. This paper reports on the findings from a mixed-methods study concerning preferred distributive justice elements in rural communities in Ontario (technocratic-based model) and Nova Scotia (community-based model) living with turbines. Residents’ perceptions of economic benefits are nuanced, but unlike other studies, this empirical work shows that both the fair distribution and the amount of local benefits are important predictors of project support. Yet, concerns around the fair distribution of benefits dominate in a regression on the adequacy of those benefits. A variety of interview and survey findings further point to the strength of traditional, profit-sharing community-based models for distributing benefits, but also more novel ideas including lowered electricity bills and tax rebates in areas home to turbines.  相似文献   
836.
We consider how ecosystem services can be incorporated into water infrastructure planning by studying the projected deepening of the Lower Weser river channel in Germany. We recalculate the project's benefit–cost ratio by integrating the monetary value of changes in different ecosystem services, as follows: (1) the restoration costs of a mitigation measure for a loss in fresh water supply for agricultural production in the estuary region, (2) the costs of a loss in habitat services, transferring the willingness to pay from a contingent valuation study to the area assessed in the environmental impact assessment, and (3) the benefits of emissions savings induced by more efficient shipping, taking a marginal abatement cost approach. We find that including monetary values for ecosystem service changes leads to a substantial drop in the benefit–cost ratio. On this basis, we argue for a reform of the standard cost–benefit analysis to facilitate more complete welfare assessments.  相似文献   
837.
We assess the role of fossil fuel prices, energy efficiency, and carbon taxation in achieving climate policy goals using a dynamic general-equilibrium model of the Portuguese economy. Given the forecasts for international fossil fuel prices, improving energy efficiency and implementing a new carbon tax have significantly different economic and budgetary effects. Greater energy efficiency reduces emissions and has a positive economic effect, but increases public and foreign debt. A carbon tax reduces emissions at a cost for the economy, but leads to positive effects on public and foreign debt. Thus, it is important to pursue both strategies. We estimate that under the reference-price scenario, a steady energy efficiency gain of 2%–2.5% per year and a carbon tax of at least 35 € per tCO2 are needed to achieve the stated goal of reducing carbon dioxide emissions by 2030 by an amount equivalent to 40% of the emissions in 1990. These views were fully integrated in a proposal presented by the Commission for Environmental Tax Reform to the Portuguese Government in September 2014, and then discussed in Parliament in November 2014, before enacting a new carbon tax on 1 January 2015.  相似文献   
838.
This study described the paradox created by the efforts of a conservation organization, which caused an emerging threat to the survival of an endangered species, as well as proposed recommendations to mitigate this paradox. In-depth interviews were conducted to investigate the problems encountered during the implementation of conservation practices by green sea turtle conservation workers (volunteers) in Lanyu, Taiwan. The staff believed that the implementation of the green sea turtle conservation measures violated the traditional cultural beliefs of the local residents (Tao/Yami ethnic group), which caused resentment by the residents towards the organization. Consequently, the residents did not cooperate with the organization and even discouraged conservation activities. In addition, green sea turtle ecotourism promoted by the conservation organization in recent years violated local customs of not having contact with green sea turtles or entering their habitats.  相似文献   
839.
Today the resources are becoming scarcer, which should not be regarded as unexhausted any more. Correspondingly, the production would be constrained by the scarcity of resources clearly. Then the economic researchers would pay much more attention to reducing the consumption of natural resources in the future. Therefore this paper brings foreword the conception of elasticity ratio of resource consumption based on the concept of elasticity and analyzes the relationship between the parameters. For the certain relationships between the elasticity ratio of resource consumption and resource consumption, this paper will try to reveal, to keep economy growing while resource consumption reducing, what conditions should be met as to the relationships among resource productivity, its growth rate, energy saving efficiency, economic growth rate and elasticity ratio of resource consumption. This paper proves the relationship between the China's energy consumption and economy growth using statistic data from 1978 to 2003.  相似文献   
840.
Two prevalent views are reviewed on China's urbanization firstly. Then, this article highlights the characteristics and pattern of urbanization in the world based on the quadrants map, using data of 118 countries or areas. The results indicate that the process of urbanization in the world excluding the data of China has slowed down gradually. A further exploration examines China's urbanization process and economic development over time, which reveals that both urbanization level and the level of economic development belong to the low-grade coordination pattern. The low level of urbanization is closely connected with the low level of economic development. Actually, China's urbanization gap appeared during 1985-1995, but it has been eliminating this urbanization gap since 1995 as a result of rapid urbanization growing. The complicated realities revealed in this analysis challenge the existing two prevalent views.  相似文献   
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