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241.
A. Veldkamp P.H. Verburg K. Kok G.H.J. de Koning J. Priess A.R. Bergsma 《Environmental Modeling and Assessment》2001,6(2):111-121
This paper introduces some of the issues that are relevant to the spatially explicit modeling of land use systems. A short overview is given of the ways and means in which a number of different land use change models describe the land use system. Specific attention is given to the empirical modeling approach used in the CLUE (Conversion of Land Use and its Effects) modeling framework. This approach is demonstrated for three case studies in China, Ecuador and the Atlantic Zone of Costa Rica. These case-studies illustrate the methodology for multi-scale analysis of land use driving factors and their application in spatially explicit modeling exercises. Model functioning, performance and limitations are discussed. The presented case-studies indicate that empirical modeling results can contribute to a better theoretic imbedding of land use change research in scale sensitive and integrated theories. 相似文献
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为获得新疆矿区当前生产规模对应的瓦斯排放基量,调查了研究矿区生产矿井的瓦斯排放现状.根据各矿区2004-2006年生产矿井的开采煤层、生产水平、生产规模和瓦斯排放等参数,对不同矿区和煤田进行了统计分析,计算了新疆矿区当前生产规模对应的瓦斯排放总量,同时对重点瓦斯防治矿区和一般瓦斯防治矿区进行了分类.调查结果表明,新疆矿区煤矿平均吨煤相对瓦斯涌出量由2004年的2.82m3/t增加到2006年的3.09 m3/t,呈逐年递增趋势; 新疆矿区2004-2006年的年平均瓦斯(CH4)排放量为1.05×108 m3/a;准南煤田(I)和塔北煤田(VI)的平均绝对瓦斯涌出量分别占全疆绝对瓦斯涌出总量的64.82%和15.19%,为相对瓦斯富集区,也是当前瓦斯防治的重点区域.按照矿区3年平均绝对瓦斯涌出量(大于1.00m3/min)或平均相对瓦斯涌出量(大于5m3/t)将新疆矿区分为重点瓦斯防治矿区和一般瓦斯防治矿区,并提出了瓦斯分类治理的具体建议.应用灰色系统理论,结合调查数据分别求解了新疆矿区原煤产量与绝对瓦斯涌出量的GM[1,1]预测模型.本研究为新疆煤炭资源后续规模开发过程中的相关环境决策和节能减排政策的实施提供了依据. 相似文献
244.
城市生活垃圾处理现状、趋势及对策建议 总被引:1,自引:0,他引:1
通过对垃圾处理方法的全面对比以及对国内外垃圾处理现状和趋势分析,垃圾焚烧发电必将成为中国特别是人多地少的发达地区未来垃圾处理的主要方式.为最大程度地防止二次污染、避免环境纠纷,从完善相关法规、强化环评管理和日常监督管理等方面提出垃圾焚烧及发电项目控制污染的相关对策和建议. 相似文献
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Data collected from the five air-quality monitoring stations established by the Taiwan Environmental Protection Administration in Taipei City from 1994 to 2003 are analyzed to assess the temporal variations of air quality. Principal component analysis (PCA) is adopted to convert the original measuring pollutants into fewer independent components through linear combinations while still retaining the majority of the variance of the original data set. Two principal components (PCs) are retained together explaining 82.73% of the total variance. PC1, which represents primary pollutants such as CO, NO(x), and SO(2), shows an obvious decrease over the last 10 years. PC2, which represents secondary pollutants such as ozone, displays a yearly increase over the time period when a reduction of primary pollutants is obvious. In order to track down the control measures put forth by the authorities, 47 days of high PM(10) concentrations caused by transboundary transport have been eliminated in analyzing the long-term trend of PM(10) in Taipei City. The temporal variations over the past 10 years show that the moderate peak in O(3) demonstrates a significant upward trend even when the local primary pollutants have been well under control. Monthly variations of PC scores demonstrate that primary pollution is significant from January to April, while ozone increases from April to August. The results of the yearly variations of PC scores show that PM(10) has gradually shifted from a strong correlation with PC1 during the early years to become more related to PC2 in recent years. This implies that after a reduction of primary pollutants, the proportion of secondary aerosols in PM(10) may increase. Thus, reducing the precursor concentrations of secondary aerosols will be an effective way to lower PM(10) concentrations. 相似文献
246.
针对现有卫星气溶胶光学厚度(AOD)产品空间分辨率和精度往往难以满足大气污染精细治理实际需求,提出了一种耦合偏差校正的统计降尺度改进模型(SDBC).该模型基于“空间尺度不变性假设”引入相关驱动因子的额外空间信息实现AOD降尺度,并在此基础上通过偏差校正进一步提升降尺度产品的精度.以1km分辨率MAIAC AOD产品为例,在北京、大湾区、台湾岛3个典型地区开展模型验证.结果表明:(1)DEM、NDVI、人口数量和土地覆盖是影响AOD变化的细节因子,在SDBC空间降尺度过程中引入可将AOD产品的空间分辨率有效提升至500m,且降尺度产品验证R2最高可达0.88;(2)顾及卫星观测几何、质量标识、大气水蒸气柱、气溶胶模式等因子的偏差校正则可进一步提升降尺度AOD产品的精度,3个地区的验证R2均在0.85以上,最高可达0.93;(3)信息熵评估结果显示SDBC模型生成的500m AOD产品提高了原始MAIAC AOD产品的空间信息量.在保留了公里级产品AOD的空间分布格局的基础上,SDBC产品也增强了细节和纹理特征、改善了边界现象和马赛克效应.研究结果证实SDBC模型能有效协同改进现有卫星A... 相似文献
247.
连云港市空气质量变化趋势分析 总被引:2,自引:0,他引:2
依据连云港市2002—2011年空气质量监测数据,对连云港市空气质量现状及其变化趋势进行系统的分析,并结合实际提出相应对策建议。结果表明,近年来连云港市空气质量总体良好,SO2浓度逐年下降,NO2浓度变化较平稳,PM10浓度下降显著。污染物浓度表现出明显的季节性特征,夏季浓度较低,春冬季较高;主城区各污染物浓度高于其他地区,但总体呈下降趋势。 相似文献
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This article takes its point of departure in two approaches to integrating climate change into Strategic Environmental Assessment (SEA): Mitigation and adaptation, and in the fact that these, as well as the synergies between them and other policy areas, are needed as part of an integrated assessment and policy response. First, the article makes a review of how positive and negative synergies between a) climate change mitigation and adaptation and b) climate change and other environmental concerns are integrated into Danish SEA practice. Then, the article discusses the implications of not addressing synergies. Finally, the article explores institutional explanations as to why synergies are not addressed in SEA practice. A document analysis of 149 Danish SEA reports shows that only one report comprises the assessment of synergies between mitigation and adaptation, whilst 9,4% of the reports assess the synergies between climate change and other environmental concerns. The consequences of separation are both the risk of trade-offs and missed opportunities for enhancing positive synergies. In order to propose explanations for the lacking integration, the institutional background is analysed and discussed, mainly based on Scott's theory of institutions. The institutional analysis highlights a regulatory element, since the assessment of climate change synergies is underpinned by legislation, but not by guidance. This means that great focus is on normative elements such as the local interpretation of legislation and of climate change mitigation and adaptation. The analysis also focuses on how the fragmentation of the organisation in which climate change and SEA are embedded has bearings on both normative and cultural-cognitive elements. This makes the assessment of synergies challenging. The evidence gathered and presented in the article points to a need for developing the SEA process and methodology in Denmark with the aim to include climate change in the assessments in a more systematic and integrated manner. 相似文献