首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Land-use change is one of the major factors that alter local and regional hydrology. For areas experiencing fast expansion of urban and agriculture areas, land-use changes often adversely affect stream flow and water resources at the local and watershed scale. The Sekong, Sesan, and Srepok (3S) Sub-basins are a part of the Lower Mekong River Basin and include land in Cambodia, Lao People’s Democratic Republic (Laos), and Viet Nam. The region is experiencing a dynamic land-use transition because of rapid changes in its economy, society, and environment. Major land-use changes include deforestation of native rain forest, expansion of agricultural and urban areas, and expansion of commercial plantation such as rubber trees. These land-use alterations have affected local and regional hydrologic processes, resulting in stream flow shortages during the dry season and flash flooding due to deforestation. In this research, deforestation in the 3S Sub-basins over the period 1993–1997 was analyzed using multi-logistic regression. The regression analysis indicated that density of agricultural cells within a 5-km radius from each forest cell and slope strongly affected the deforestation process. A land-use forecast model to simulate deforestation and urbanization sites was developed in GIS based on local land-use change trends. The model was applied to 2003 land use to forecast 2033 land use and future water demand, which was further compared with present stream flow measurements during the dry season at various places in the region. The entire approach from the land-use forecast to its impact assessment on stream flow could help local stakeholders understand watershed-wide future water resources risks and develop future water resources plans. With the 3S Sub-basins being used as a case study area, this article presents a land-use forecast tool; simulated 2033 land-use and water demand; and the estimation of the impact of the forecasted future water demand on the local stream flow.  相似文献   

2.
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  相似文献   

3.

Local, regional, and global processes affect deforestation and land-use changes in the Brazilian Amazon. Characteristics are: direct conversions from forest to pasture; regional processes of indirect land-use change, described by the conversion of pastures to cropland, which increases the demand for pastures elsewhere; and teleconnections, fueled by the global demands for soybeans as animal fodder. We modeled land-use changes for two scenarios Trend and Sustainable Development for a hot spot of land-use change along the BR-163 highway in Mato Grosso and Pará, Brazil. We investigated the differences between a coupled modeling approach, which incorporates indirect land-use change processes, and a noncoupled land-use model. We coupled the regional-scale LandSHIFT model, defined for Mato Grosso and Pará, with a subregional model, alucR, covering a selected corridor along the BR-163. The results indicated distinct land-use scenario outcomes from the coupled modeling approach and the subregional model quantification. We found the highest deforestation estimates returned from the subregional quantification of the Trend scenario. This originated from the strong local dynamics of past deforestation and land-use changes. Land-use changes exceeded the demands estimated at regional scale. We observed the lowest deforestation estimates at the subregional quantification of the Sustainable Development story line. We highlight that model coupling increased the representation of scenario outcomes at fine resolution while providing consistency across scales. However, distinct local dynamics were explicitly captured at subregional scale. The scenario result pinpoints the importance of policies to aim at the cattle ranching sector, to increase land tenure registration and enforcement of environmental laws.

  相似文献   

4.
Scenarios have become a powerful tool in integrated assessment and policy analysis for climate change. Socio-economic and climate scenarios are often combined to assess climate change impacts and vulnerabilities across different sectors and to inform risk management strategies. Such combinations of scenarios can also play an important role in enabling the interaction between experts and other stakeholders, framing issues and providing a means for making explicit and dealing with uncertainties. Drawing on experience with the application of scenarios to climate change assessments in recent Dutch research, the paper argues that scenario approaches need to be matched to the frames of stakeholders who are situated in specific decision contexts. Differentiated approaches (top-down, bottom-up and interactive) are needed to address the different frames and decision-making contexts of stakeholders. A framework is proposed to map scenarios and decision contexts onto two dimensions: the spatial scale of the context and the starting point of approach used in scenario development (top-down, bottom-up or incident-driven). Future climate and socio-economic scenario development will be shaped by the need to become better aligned with multiple interacting uncertainties salient to stakeholders.  相似文献   

5.
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   

6.
Over the past decades, significant experience has been gained in demand-driven research on climate change in many countries. In the Netherlands, a competitive call for proposals for large research programmes at the interface between policy, science and private sector was issued in 2001. Members of the Dutch climate research community proved they were able to develop two large research programme proposals which were funded: ‘Climate changes Spatial Planning’ and its successor ‘Knowledge for Climate’. The programmes ran from 2004 to 2012 and from 2008 to 2014, respectively. Both programmes can be considered as a 10-year research programme experiment to develop knowledge about both the climate system and climate compatible development by crossing disciplines, institutions and national research funding strategies. Within this 10-year period, a trend can be observed in which a ‘top-down’ climate impact assessment approach is increasingly combined with a ‘bottom-up’ approach. Based on the 15 articles presented in this special issue (and others), we argue that this development has enriched both fundamental and applied research on climate adaptation. Despite the predominantly Dutch-oriented scope of the presented research, we believe that such experiences can be of international interest. Climate adaptation research finds itself in between global systems knowledge on the one hand and practical needs and experiences at the local, regional and national level on the other. This demands the utmost from all actors involved to enable an efficient and constructive flow and use of knowledge and expertise.  相似文献   

7.
Analyzing the interaction between environmental policies and farmers’ responses to them is an important dimension to understand regional agro-ecosystem sustainability. We examine land-use outcomes of perhaps the largest government-planned rural reforestation program in the history of humankind, China’s “Grain for Green” (GFG) policy from 1999 to 2006. Specifically, we simulate household responses to the GFG policy in Western China’s Shaanxi Province, a region experiencing acute climate and land change-related environmental degradation. We develop a “farmer group decision-making model” to simulate the probability of land-use change. Elevation, slope, and farm household characteristics emerge as key factors influencing farmers’ land-use decisions and subsequent land-use patterns. Land reversion and abandonment in the study area have been significantly affected by the GFG program. Policy recommendations suggest potential avenues to enhance the effectiveness of the GFG program and to improve the efficient use of under-used farmland. Results may help inform the Chinese government as it crafts policy guiding a coupled rural migration and reforestation program of unprecedented scale.  相似文献   

8.
中国农村居民点用地变化的社会经济因素分析   总被引:3,自引:0,他引:3  
基于2000-2008年省级单元的土地利用和社会经济统计数据,探讨来自区域、城镇和农村的社会经济因素对农村居民点用地扩张的作用机制,认为农村居民点用地扩张受到农村自身社会经济发展和城镇社会经济发展的双重作用,一方面区域和农村社会经济推动了农村居民点用地规模扩张,另一方面工业化和城镇化进程引起的城镇空间扩张,缓解了农村居民点用地扩张的趋势,在此"一增一减"双重作用下,农村居民点用地呈现缓慢增长趋势。相比于来自区域和城镇的社会经济因素,农村自身的社会经济发展因素对于省级单元的农村居民点用地扩张的影响更为重要。不论是对于来自城镇或是农村的社会经济因素,产出效应都比投资和收入效应更明显,在控制产出效应的情况下,来自于城镇和区域的投资和收入效应不再显著。为控制农村居民点用地过度扩张,政府应在健康快速的工业化和城镇化进程中,实施城乡建设用地增减挂钩政策,加大土地开发整理和复垦力度,积极投资农村,提高农用地产出,以有效引导农村居民点用地节约集约利用。  相似文献   

9.
协调经济增长与土地资源利用关系是经济发展提质增速及可持续城市建设的关键,为探索城市建设用地扩张与经济增长的时空演变特征及其耦合趋势,运用重心模型、Tapio弹性指数对建设用地扩张与经济增长的空间耦合关系与脱钩状态进行测度,并构建计量模型,检验了经济、社会、政策等因素对城市扩张的影响。结果表明:(1)中国经济与建设用地规模保持双增长态势,中西部地区近年来建设用地扩张更加明显,经济和建设用地重心均呈现西南方向迁移,但空间耦合性逐渐减弱;(2)中国经济与建设用地脱钩关系不断恶化,脱钩状态分布格局变化明显,东部地区脱钩状况逐渐改善;(3)社会经济因素是城市扩张的关键推动力,政策、产业集聚等也在一定程度上促进城市扩张。未来要重点加强对中西部地区城市土地扩张的管控,对于东部地区而言,则要在经济转型的过程中寻求产业转型与土地利用转型的契合点,追求城市的精明增长。  相似文献   

10.
Understanding the importance of cross-sectoral implications of climate and socio-economic change in Scotland is essential for adaptation policy. This study explored the direct and indirect sectoral impacts of future change using the CLIMSAVE Integrated Assessment Platform. There is great spatial diversity in projected impacts across Scotland, and increasing uncertainty in the direction of change of impacts from the national to regional scale associated with climate uncertainty. Further uncertainty associated with socio-economic change results in 6 out of 13 indicators (artificial surfaces, biodiversity vulnerability, forest area, land-use intensity, irrigation usage and land-use diversity) with robust directions of change at the national scale and only three (artificial surfaces, forest area and irrigation usage) that are robust across all regions of Scotland. Complex interactions between socio-economic scenario assumptions (e.g. food imports, population and GDP), climatic suitability and agricultural productivity and profitability lead to significant national and regional changes in the distribution and extent of land cover types, with resultant cross-sectoral interactions with water, forestry and biodiversity. Consequently, stakeholders characterised robust adaptation policy options, within the CLIMSAVE participatory process, as those beneficial to society (and the country) in all scenarios, irrespective of the direction of change of the impacts. The integration in CLIMSAVE of a participatory scenario development process and an integrated participatory modelling framework has allowed the exploration of future uncertainty in a structured approach and better represented the importance of qualitative information and the social and institutional contexts within adaptation research.  相似文献   

11.
In the recent past, the Alpine Lech valley (Austria) experienced three damaging flood events within 6 years despite the various structural flood protection measures in place. For an improved flood risk management, the analysis of flood damage potentials is a crucial component. Since the expansion of built-up areas and their associated values is seen as one of the main drivers of rising flood losses, the goal of this study is to analyze the spatial development of the assets at risk, particularly of residential areas, due to land use changes over a historic period (since 1971) and up to possible shifts in future (until 2030). The analysis revealed that the alpine study area was faced to remarkable land use changes like urbanization and the decline of agriculturally used grassland areas. Although the major agglomeration of residential areas inside the flood plains took place before 1971, a steady growth of values at risk can still be observed until now. Even for the future, the trend is ongoing, but depends very much on the assumed land use scenario and the underlying land use policy. Between 1971 and 2006, the annual growth rate of the damage potential of residential areas amounted to 1.1 % (‘constant values,’ i.e., asset values at constant prices of reference year 2006) or 3.0 % (‘adjusted values,’ i.e., asset values adjusted by GDP increase at constant prices of reference year 2006) for three flood scenarios. For the projected time span between 2006 and 2030, a further annual increase by 1.0 % (‘constant values’) or even 4.2 % (‘adjusted values’) may be possible when the most extreme urbanization scenario ‘Overall Growth’ is considered. Although socio-economic development is regarded as the main driver for increasing flood losses, our analysis shows that settlement development does not preferably take place within flood prone areas.  相似文献   

12.
In this study, we describe a spatially explicit scenario analysis of global change effects on the potential future trade-offs and conflicts between agriculture, energy generation, and grassland and wetland conservation in North Dakota (ND), USA. Integrated scenarios combining global policy, oil security, and climate change were applied to North Dakota using a spatial multi-criteria analysis shell. Spatial data describing climate changes and grassland, wetland, cropland, and energy distributions were used to characterize the geographical environment. The final multi-criteria framework examined the potential trade-offs between climate change, agricultural expansion, and energy generation resulting from global change scenarios on one hand, and the current footprint of wetlands and grasslands for six regions of ND that capture the major climate gradients and differences in land use. The results suggest that the tension between regional climate changes that may limit agricultural expansion, and global changes in food and energy security and commodity prices that favor agricultural expansion, may focus a zone of potential pressure on grasslands and wetland conversion in central ND and the Prairie Pothole Region. The balance between conservation programs, commodity prices, and land parcel productivity may determine grassland conversion, while wetland outcomes may almost totally depend upon regional climate change.  相似文献   

13.
The study presents three scenarios of land use and cover change (LUCC), the most important factor for environmental degradation in southern Mexico. We developed story lines and quantitative projections for regional scenarios based on historic LUCC processes, environmental policies, socioeconomic drivers, stakeholder consultations and official planning documents to gain a better understanding of drivers of LUCC, and quantitative scenarios were modeled with DINAMICA-EGO. Regionally specific interactions between social and natural systems are recognized, and detrimental policies and policy options for landscape conservation and management for sustainability are acknowledged in a base line, variant and alternative scenario. Incongruent policies and ineffective ground implementation of conservation actions were identified as the critical underlying drivers of deforestation and forest degradation that could lead to a severe reduction in natural forests, while the local socioeconomic situation stays precarious. The baseline scenario parts from an analysis of historic LUCC processes and shows the consequences of LUCC tendencies: 73% of temperate forests and 50% of tropical forests would get deforested until 2030. In the variant scenario, these tendencies are adjusted to planning goals extracted from official documents and recent changes in public policies. The alternative scenario further addresses policy options for fostering conservation and sustainable development, but because of the time lag of implementation, still 59% of temperate forests and 36% of tropical forest would get lost until 2030. Nevertheless, this represents a reduction of 13% of forest loss and 11% less pastureland due to the proposed measures of conservation, and sustainable management, including strategies for reforming agricultural systems, agricultural and forestry policies and trade, land tenure and livelihood risk management.  相似文献   

14.
中美应对气候变化的政策过程比较   总被引:1,自引:0,他引:1  
中国应对气候变化的政策过程具有明显的自上而下特征,美国应对气候变化的政策过程则呈现出自下而上的特点.中美之所以形成两种截然不同的气候变化政策过程,主要原因在于两国政治制度和经济基础的不同.中国集中式民主使中央政府具有绝对的政治权威,中央政府的决策能够迅速地传递到各级政府并得以实施.作为一个代议制国家,美国中央政府的决策受各种利益集团的影响较大,立法过程更为复杂和漫长.在以经济增长为基础的政治锦标赛下,中国的地方政府更关心经济增长;美国的经济已经高度发达,民众对气候变化的关心程度更高,同时,美国的地方政府在环境立法上拥有更多的自主权,这导致美国的地方政府纷纷出台各自的应对气候变化政策.美国的应对气候变化政策过程过于缓慢,但自下而上的政策形成体系使地方政府提出的减排目标更适合于自身情况,有助于实现较低的减排成本;中国应对气候变化的政策过程具有高效性,但自上而下的政策形成体系忽视了地区差别,对各地方政府造成了较大的减排压力,从而不得不付出更高的减排成本.  相似文献   

15.
This article reviews critical linkages between land-use transition and human health in the Himalayan region by applying ecosystem approaches to human health (or EcoHealth). Land-use transition in the Himalayan and similar regions includes sedentarization, agricultural intensification, habitat modification, migration, change of livelihoods and lifestyles, biodiversity loss, and increasing flash floods. These transitions, which can have impacts on human health, are driven by state policies, a market economy, and climate change. Human health is dependent on access to ecosystem services for food, nutrition, medicine, fiber and shelter, fresh water, and clear air. Ecosystem management has been a key means of controlling disease vectors and creating suitable habitats for human well-being. The paper identifies the web of environmental factors that influence human health. Institutional and policy issues for land-use and health transitions are also discussed.  相似文献   

16.
17.
This paper discusses the application of qualitative scenarios to understand community vulnerability and adaptation responses, based on a case study in the Slave River Delta region of the Northwest Territories, Canada. Three qualitative, graphic scenarios of possible alternative futures were developed, focusing on two main drivers: climate change and resource development. These were used as a focal point for discussions with a cross-section of residents from the community during focus groups, interviews and a community workshop. Significant overlap among the areas of perceived vulnerability is evident among scenarios, particularly in relation to traditional land use. However, each scenario also offers insights about specific challenges facing community members. Climate change was perceived to engender mostly negative livelihood impacts, whereas resource development was expected to trigger a mix of positive and negative impacts, both of which may be more dramatic than in the “climate change only” scenario. The scenarios were also used to identify adaptation options specific to individual drivers of change, as well as more universally applicable options. Identified adaptation options were generally aligned with five sectors—environment and natural resources, economy, community management and development, infrastructure and services, and information and training—which effectively offer a first step towards prioritization of “no regrets” measures. From an empirical perspective, while the scenarios highlighted the need for bottom-up measures, they also elucidated discussion about local agency in adaptation and enabled the examination of multi-dimensional impacts on different community sub-groups. An incongruity emerged between the suite of technically oriented adaptation options and more socially and behaviourally oriented barriers to implementation. Methodologically, the qualitative scenarios were flexible, socially inclusive and consistent with the Indigenous worldview; allowed the incorporation of different knowledge systems; addressed future community vulnerability and adaptation; and led to the identification of socially feasible and bottom-up adaptation outcomes. Despite some caveats regarding resource requirements for participatory scenario development, qualitative scenarios offer a versatile tool to address a range of vulnerability and adaptation issues in the context of other Indigenous communities.  相似文献   

18.
The effectiveness of climate adaptation policies in one sector can be compromised or aided by policies developed in another sector. When the focus of adaptation is a single geographical region, this potential for interaction between sectoral policies is heightened due to spatial, political and functional proximities. This paper analyses interactions within three suites of climate adaptation options developed for Australia’s ‘South-East Queensland’ region relating to: (1) wetland migration, coastal infrastructure and planned retreat; (2) urban water security and energy demand; and (3) terrestrial biodiversity and agricultural viability. Using the concept of ‘institutional interplay’ to structure a process of dialogue amongst researchers, we identify a number of critical implementation requirements for successful regional-scale adaptation. There is a need for greater focus on neighbourhood or sub-regional scales of policy design and intervention, particularly for the coordination of adapted infrastructure and services to households. Policy-makers must also be more explicit in considering broader drivers of land-use change and economic adjustment likely to impact on proposed adaptations. In considering these issues, our paper also demonstrates a process for conducting cross-sectoral syntheses that can be employed in other regional-scale adaptation studies.  相似文献   

19.
基于广泛系统的文献梳理和总结,凝练了“十二五”以来中国应对气候变化政策和行动的现状、特点及成效,并提出针对性建议。主要结论包括:从外部环境看,国际形势对中国应对气候变化事业的推动作用呈现递减态势,之前“以外促内”的国内气候治理特点逐步转化为“内生动力为主”和“内外协调”;从政策制定和执行模式看,“集思广益”“上书模式”持续,“上下互动”“智库支持”的政策学习特点更加明显;从政策体系上看,已经形成相对成熟的符合中国国情的完整体系,推动气候治理能力显著提高;从政策总体特点看,呈现规划主导并引领、行政手段先行市场机制跟进、由点到面有序扩展、环境与气候协同治理、中央和地方互动博弈形成动态平衡、短期内政策成本较高等特点。“十二五”至今,中国应对气候变化政策行动效果明显,提前实现了2020年应对气候变化目标,并在污染治理、经济发展等方面产生广泛协同效应。“十三五”中期以来,中国应对气候变化组织管理机构进行了重大调整,从中央到地方气候政策和行动进入调整阶段。同时,更加强调气候政策和环境政策的协同。展望未来,中国应对气候变化政策和行动应该尽快走出调整期,充分利用新体制的优势,以碳总量控制目标为抓手,坚定推动以全国碳排放权交易为中心、多措互补的政策体系,注重适应行动以应对不断放大的气候风险,继续提高公众对应对气候变化政策的认知度、接受度和参与度,并不断加强技术研发和储备。  相似文献   

20.
Aggregated consideration of both climate and socio-economic change in a coarse spatial resolution is a central feature for scenario development in global change research. Downscaling of the supposed aggregated changes is a necessary prerequisite for the assessments of global change at the regional scale. The present paper describes the method and results of an approach to develop and to apply scenarios of socio-economic change at a sub-national level, which are consistent with global change scenarios. National and regional models of economic and demographic development are used to regionalise drivers of socio-economic change. Scenario results are subsequently applied in order to analyse the impacts of socio-economic and climatic changes on water management issues in the Elbe river basin. Starting from global IPCC-Emissions Scenarios and taking up their key points, we formulate two scenarios for the German and Czech parts of the Elbe catchment areas. We present a system of demographic and economic models, designed to consistently project socio-economic developments at a national and sub-national level and, thus, to quantitatively illustrate our scenarios. The results show that in a scenario that assumes continued globalisation and emphasis on economic growth, export orientation will result in a comparatively high share of manufacturing. Growth spreads from centres to peripheral regions. Still, at the national level, the increase in population and employment will be modest and create little additional pressure, but water stress will be considerably stronger on a regional basis, namely in metropolitan areas such as Prague, Berlin and Hamburg. In a scenario where economic goals are balanced with ecologic and social ones, growth is weaker and the weight of the service sector increases more rapidly, thus easing the driving forces for overall water demand and pollution. However, as in this scenario regional metropolitan centres develop at the cost of peripheral regions, regional development is more selective and the driving forces for potential water stress will diverge spatially.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号