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381.
Modeling the spatial dynamics of regional land use: the CLUE-S model 总被引:95,自引:3,他引:92
Verburg PH Soepboer W Veldkamp A Limpiada R Espaldon V Mastura SS 《Environmental management》2002,30(3):391-405
Land-use change models are important tools for integrated environmental management. Through scenario analysis they can help
to identify near-future critical locations in the face of environmental change. A dynamic, spatially explicit, land-use change
model is presented for the regional scale: CLUE-S. The model is specifically developed for the analysis of land use in small
regions (e.g., a watershed or province) at a fine spatial resolution. The model structure is based on systems theory to allow
the integrated analysis of land-use change in relation to socio-economic and biophysical driving factors. The model explicitly
addresses the hierarchical organization of land use systems, spatial connectivity between locations and stability. Stability
is incorporated by a set of variables that define the relative elasticity of the actual land-use type to conversion. The user
can specify these settings based on expert knowledge or survey data. Two applications of the model in the Philippines and
Malaysia are used to illustrate the functioning of the model and its validation. 相似文献
382.
Kennett SA 《Environmental management》2002,30(5):0595-0608
Biosphere greenhouse gas (GHG) management consists of preserving and enhancing terrestrial carbon pools and producing biomass
as a fossil fuel substitute. The discussion of this topic has focused primarily on carbon-accounting and project-level issues,
particularly relating to carbon sequestration as a source of emissions credits under the Kyoto Protocol. While international
consensus on these matters is needed, this paper argues that an important domestic policy agenda also deserves attention.
National policies for biosphere GHG management are necessary to bring about large-scale changes in land-use, forestry, and
agricultural practices and can address some of the technical and policy issues that have proven to be particularly problematic
from carbon-accounting and project-level perspectives. These policies should minimize land-use and resource-management conflicts,
account for collateral benefits, and ensure institutional compatibility with existing resource-management regimes. Issues
relating to project permanence, leakage, and transaction costs should also be addressed. A range of policy instruments should
be used and biosphere GHG management should be one component of an integrated approach to environmental and resource management.
Countries promoting biosphere GHG management as an important element of their climate change strategies should be developing
these domestic policies to complement international negotiations and to demonstrate that carbon sequestration and biomass
production can make an effective contribution to the stabilization of atmospheric GHG concentrations. 相似文献
383.
Advancement of renewables in Bangladesh and Thailand: Policy intervention and institutional settings
This article reviews and analyses the advancement of renewable sources of energy in Bangladesh and Thailand in terms of policy intervention and institutional settings. Since renewable forms of energy emit far smaller amounts of greenhouse gas compared with fossil fuels, their use should mitigate climate change impacts while contributing to the provision of energy services. The article turns first to a review of energy–environment trends and the potential for renewables in these two nations. It then discusses strategies for the advancement of renewables. It is argued that further significant efforts can be made towards the advancement of renewables in Bangladesh and Thailand. These two nations could also learn from the experience in industrialized nations and other developing nations with regard to requisite policy instruments and processes. A number of barriers remain to the advancement of renewables, especially in terms of policy arrangements, institutional settings, financing mechanisms and technologies. Resources, cooperation and learning are required in order to overcome such barriers and to foster the development of necessary policy measures. Implementation of the clean development mechanism (CDM) under the Kyoto Protocol, and replication and adaptation of effective strategies from other settings are possible avenues for this. 相似文献
384.
Catherine Denault Robert G. Millar Barbara J. Lence 《Journal of the American Water Resources Association》2006,42(3):685-697
ABSTRACT: Stationarity of rainfall statistical parameters is a fundamental assumption in hydraulic infrastructure design that may not be valid in an era of changing climate. This study develops a framework for examining the potential impacts of future increases in short duration rainfall intensity on urban infrastructure and natural ecosystems of small watersheds and demonstrates this approach for the Mission/Wagg Creek watershed in British Columbia, Canada. Nonstationarities in rainfall records are first analyzed with linear regression analysis, and the detected trends are extrapolated to build potential future rainfall scenarios. The Storm Water Management Model (SWMM) is used to analyze the effects of increased rainfall intensity on design peak flows and to assess future drainage infrastructure capacity according to the derived scenarios. While the framework provided herein may be modified for cases in which more complex distributions for rainfall intensity are needed and more sophisticated stormwater management models are available, linear regressions and SWMM are commonly used in practice and are applicable for the Mission/Wagg Creek watershed. Potential future impacts on stream health are assessed using methods based on equivalent total impervious area. In terms of impacts on the drainage infrastructure, the results of this study indicate that increases in short duration rainfall intensity may be expected in the future but that they would not create severe impacts in the Mission/Wagg Creek system. The equivalent levels of imperviousness, however, suggest that the impacts on stream health could be far more damaging. 相似文献
385.
低温湿式空气氧化法处理废碱液的研究 总被引:18,自引:0,他引:18
对采用低温湿式空气氧化法处理炼油和乙烯废碱液进行了研究。考察了停留时间对废碱液中硫化物的氧化、氧化产物的形态、COD和酚去除率的影响,反应温度对废碱液中污染物氧化反应的影响。试验结果表明,废碱液的脱臭效果很好,S^2-的氧化产物以S2O3^2-和SO4^2-2种形式共存;酚、COD的去除率及S^2-的氧化反应停留时间影响小,受反应温度影响明显;废碱液的S^2-的酚浓度相当时,COD去除率一 般低于40%, 废碱液的S^2-浓度远大于酚浓度时,废碱液的COD去除率为40%-70%;废碱液中酚的质量浓度大于20000mg/L时才有回收价值。 相似文献
386.
387.
通过对四川省科技人力资源的潜力、结构变化的分析,提出建立统一规范的科技人才培养经费投入政策,加强科技人才资源的再开发,不拘一格引进科技人才,建立四川省科技人力资源监测系统等对策。 相似文献
388.
389.
喀斯特石山地区社会经济与生态环境可持续发展系统研究:以桂西北为例 总被引:5,自引:0,他引:5
本建立了广西西北部喀斯特石山地区可持续发展的系统动力学模型。并用DYNAMO程序预测了未来20年桂西北地区的人口、工业、农业、第三产业,生态环境,土地资源,社会总产值,人均国民收人等的动态变化趋势,结果显示,该地区由于人口,工业资产增加使物质和能源消耗增长太快,而对污染治理的投入又太少,导致桂西北地区的生存环境质量下降,因此应当加大对污染治理的投入力度,改善区域环境质量,这是实现息烽县区域可持续发展的关键,根据区域特点探讨了桂西北喀斯特贫困山区的形成演化,提出了可持续发展的途径。 相似文献
390.
Modeling the relationships between land use and land cover on private lands in the Upper Midwest, USA 总被引:4,自引:0,他引:4
This paper presents an approach to modeling land-cover change as a function of land-use change. We argue that, in order to model the link between socio-economic change and changes in forest cover in a region that is experiencing residential and recreational development and agricultural abandonment, land-use and land-cover change need to be represented as separate processes. Forest-cover change is represented here using two transition probabilities that were calculated from Landsat imagery and that, taken together, describe a Markov transition matrix between forest and non-forest over a 10-year period. Using a three-date land-use data set, compiled and interpreted from digitized parcel boundaries, and scanned aerial photography for 136 sites (c. 2500 ha) sampled from the Upper Midwest, USA, we test functional relationships between forest-cover transition probabilities, standardized to represent changes over a decade, and land-use conditions and changes within sample sites. Regression models indicated that about 60% of the variation in the average forest-cover transition probabilities (i.e. from forest to non-forest and vice versa) can be predicted using three variables: amount of agricultural land use in a site; amount of developed land use; and the amount of area increasing in development. In further analysis, time lags were evaluated, showing that agricultural abandonment had a relatively strong time-lag effect but development did not. We demonstrate an approach to using forest-cover transition probabilities to develop spatially-constrained simulations of forest-cover change. Because the simulations are based on transition probabilities that are indexed to a particular time and place, the simulations are improved over previous applications of Markov transition models. This modeling approach can be used to predict forest-cover changes as a result of socio-economic change, by linking to models that predict land-use change on the basis of exogenous human-induced drivers. 相似文献