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1.
Dynamic simulation models allow an integrated representation of human and biophysical driving forces, to test their influence on land use. Dynamic models emphasise the interactions among the components of the system and take into account feedback loops and threshold effects. In this paper, the SALU model was used to generate “what-if” scenarios to explore hypotheses on the relative role of driving forces of land-use change in the Sudano-sahelian countries of Africa. The model simulations provided useful insights to better understand the processes of land-use change. Rural population growth represents a larger stimuli for land-use change than urban population growth. Demographic variables have a greater impact on land use than recurring droughts. The demographic driving forces are slow variables while rainfall is a fast variable. Recurring droughts could be viewed as trigger events, and urban population growth and consumption as mediating factors, while rural population growth defines long-term trends. Technological change defines thresholds in land use. Land-use change results from interactions between driving forces. The timing of occurrence of drought with respect to transitions in land use has a major impact on land-use change. Polices aimed at protecting pastoral land and supporting agricultural intensification both contribute to maintain pastoral activities. Simulating a conservative carrying capacity has a major impact on land use predictions. By examining environmental, social and economic implications of various land-use scenarios, the modelling approach adopted in SALU can provide support for decision-making.  相似文献   

2.
徐倩  李阳兵  黄娟 《中国岩溶》2018,37(4):545-554
选取贵州省清镇市近郊村域王家寨地区为研究对象,在GIS支持下,利用该区域1963年、1982年、2005年、2010年和2015年5期土地利用图形数据叠加分析,提取出研究区50余年来的土地利用/覆盖信息,并结合相应的社会经济统计数据,分析了其驱动力因子,其结果表明:(1)1963—2015年间,土地覆盖类型的总体变化为高被草地和平坝旱耕地明显减少,低被草地、农村居民点、工矿用地、公路用地面积大幅增加,其中,平坝旱耕地有向经济效益更高的土地利用方式转变的趋势;（2）景观格局演变的总体趋势是:自1963年起,斑块数量、斑块密度持续增加,到2015年呈下降趋势,而最大斑块指数逐年减小,形状趋于不规则,同时,近50年景观的多样性指数持续增加;（3）区内土地利用/覆盖和景观格局呈阶段性变化,从1963年到2005年,坡地土地利用活动较强,2005年后,平地土地利用强度增加、农业逐渐转型、聚落持续扩展;（4）区内土地利用及景观格局的变化主要受经济、人口和政策因素的影响。   相似文献   

3.
Information on use/land cover change is important for planners and decision makers to implement sustainable use and management of resources. This study was intended to assess the land use land cover (LULC) change in the Koga watershed. The MSS of 1973, TM images of 1986, 1995 and 2011 were used together with survey and demographic data to detect the drivers of land cover changes. The result revealed that a remarkable LULC change occurred in the study area for the past thirty eight years. The area of cultivated and settlement has increased by 7054.6 ha, while, grass and bush lands decreased by 4846.5 and 3376 ha respectively. Wetland also declined from 580.2 ha to 68.3 ha. The growing demand for cultivable land and fuel wood were the major causes to the deterioration of grass and bush lands. Hence, the appropriate land use policy should be employed to sustain available resource in the watershed.  相似文献   

4.
Adaptive governance is the use of novel approaches within policy to support experimentation and learning. Social learning reflects the engagement of interdependent stakeholders within this learning. Much attention has focused on these concepts as a solution for resilience in governing institutions in an uncertain climate; resilience representing the ability of a system to absorb shock and to retain its function and form through reorganisation. However, there are still many questions to how these concepts enable resilience, particularly in vulnerable, developing contexts. A case study from Uganda presents how these concepts promote resilient livelihood outcomes among rural subsistence farmers within a decentralised governing framework. This approach has the potential to highlight the dynamics and characteristics of a governance system which may manage change. The paper draws from the enabling characteristics of adaptive governance, including lower scale dynamics of bonding and bridging ties and strong leadership. Central to these processes were learning platforms promoting knowledge transfer leading to improved self-efficacy, innovation and livelihood skills. However even though aspects of adaptive governance were identified as contributing to resilience in livelihoods, some barriers were identified. Reflexivity and multi-stakeholder collaboration were evident in governing institutions; however, limited self-organisation and vertical communication demonstrated few opportunities for shifts in governance, which was severely challenged by inequity, politicisation and elite capture. The paper concludes by outlining implications for climate adaptation policy through promoting the importance of mainstreaming adaptation alongside existing policy trajectories; highlighting the significance of collaborative spaces for stakeholders and the tackling of inequality and corruption.  相似文献   

5.
Modeling the suitability of land to support specific land uses is an important and common GIS application. Three classic models, specifically pass/fail screening, graduated screening and weighted linear combination, are examined within a more general framework defined by fuzzy logic theory. The rationale underlying each model is explained using the concepts of fuzzy intersections, fuzzy unions and fuzzy averaging operations. These fuzzy implementations of the three classic models are then operationalized and used to analyze the distribution of kudzu in the conterminous United States. The fuzzy models achieve better predictive accuracies than their classic counterparts. By incorporating fuzzy suitability membership of environment factors in the modeling process, these fuzzy models also produce more informative fuzzy suitability maps. Through a defuzzification process, these fuzzy maps can be converted into conventional maps with clearly defined boundaries, suitable for use by individuals uncomfortable with fuzzy results.  相似文献   

6.
区域土地利用变化驱动力研究前景展望   总被引：29，自引：0，他引：29  
区域土地利用变化驱动力研究旨在从典型区域角度揭示土地利用变化背后的真正动因及其作用机理，进而动态模拟、预测区域土地利用变化过程。土地利用系统的自组织性及其内驱动因子作用的复杂性，决定了其研究必须与某一特定区域相联系，以便确定合适的可定量指标来体现外生驱动因子的驱动效果。系统地识别土地利用系统在不同控制状态下的驱动因子及其多种时空尺度效应，建立具有综合模拟的区域土地利用变化动态模型，能减少土地利用系统通常受临界值域和突变所左右的局面。区域土地利用变化驱动因子识别、区域土地利用变化驱动机制分析、区域土地利用变化驱动过程模拟等的研究现状表明，为更好地理解区域土地利用变化的机制和原因，测度现有及未来土地利用变化的速率、过程和地点，支持政府相关决策的制定与实施，促使区域土地利用变化向有利于人类的方向发展,区域土地利用变化驱动力分析应优先考虑以下研究领域：①驱动力因子识别及其作用效应的尺度依赖性；②驱动力因子的贡献量化及其在具体区域的非均一分布；③驱动力因子作用过程的自然反馈机制模型化。 [HT5H]关〓键〓词：[HT5K]  相似文献   

7.
李秀荣  陈洁 《山东地质》2011,(6):48-50,53
建设用地供应审批之后,加强对其开发利用情况的跟踪监管,是落实节约集约用地政策、遏制违法违规用地的重要途径。成武县对新增建设用地严格规范出让合同的内容,加强对土地开发利用的监管;对已批存量建设用地,通过存量盘活、资源整合等一系列监管措施,有效促进了已供土地及时按规定开发,保证了各类住房及时建成,切实提高了土地供应和开发利用效率。  相似文献   

8.
In the Himalayan states of India, with increasing population and activities, large areas of forested land are being converted into other land-use features. There is a definite cause and effect relationship between changing practice for development and changes in land use. So, an estimation of land use dynamics and a futuristic trend pattern is essential. A combination of geospatial and statistical techniques were applied to assess the present and future land use/land cover scenario of Gangtok, the subHimalayan capital of Sikkim. Multi-temporal satellite imageries of the Landsat series were used to map the changes in land use of Gangtok from 1990 to 2010. Only three major land use classes (built-up area and bare land, step cultivated area, and forest) were considered as the most dynamic land use practices of Gangtok. The conventional supervised classification, and spectral indices-based thresholding using NDVI (Normalized Difference Vegetation Index) and SAVI (Soil Adjusted Vegetation Index) were applied along with the accuracy assessments. Markov modelling was applied for prediction of land use/land cover change and was validated. SAVI provides the most accurate estimate, i.e., the difference between predicted and actual data is minimal. Finally, a combination of Markov modelling and SAVI was used to predict the probable land-use scenario in Gangtok in 2020 AD, which indicted that more forest areas will be converted for step cultivation by the year 2020.  相似文献   

9.
Although contemporary policy making is substantially affected by consultants, little is known about the interconnection of their role inside policy making networks and their key product – knowledge. This paper matches the approaches on Policy Mobilities (PM) and Territorial Knowledge Dynamics (TKD) to fill this theoretical gap. By exploring the synergies of both concepts, a research agenda is suggested that enables to investigate the multi-facetted entanglements of knowledge and policy making dynamics as well as what stake consultants have in this complex assemblage. Accordingly, this paper claims appreciation of ‘variegated consultocracies’ rather than global homogeneity of consultants’ engagement in policy making processes by explicating better integration of ‘scale, ‘time’, and actors’ embeddedness into PM. The paper thus primarily aims to provide a solid theoretical and methodological basis for exploring the complex dynamics consultants take part in, and how they in turn impact policy making processes.  相似文献   

10.
The questions of how land use change affects climate, and how climate change affects land use, require examination of societal and environmental systems across space at multiple scales, from the global climate to regional vegetative dynamics to local decision making by farmers and herders. It also requires an analysis of causal linkages and feedback loops between systems. These questions and the conceptual approach of the research design of the Climate-Land Interaction Project (CLIP) are rooted in the classical human-environment research tradition in Geography.This paper discusses a methodological framework to quantify the two-way interactions between land use and regional climate systems, using ongoing work by a team of multi-disciplinary scientists examining climate-land dynamics at multiple scales in East Africa. East Africa is a region that is undergoing rapid land use change, where changes in climate would have serious consequences for people’s livelihoods, and requiring new coping and land use strategies. The research involves exploration of linkages between two important foci of global change research, namely, land use/land cover (LULC) and climate change. These linkages are examined through modeling agricultural systems, land use driving forces and patterns, the physical properties of land cover, and the regional climate. Both qualitative and quantitative methods are being used to illustrate a diverse pluralism in scientific discovery.  相似文献   

11.
Until the mid-1980s, transport policy was considered by many as one of the least successful domains of the European integration project. However, from the early 1990s onwards, there are clear signs of a single European transport policy, along with the accompanying implementation of infrastructure projects. What is the explanation for such a change in pace? This paper aims to offer insight in these processes by looking at the mechanisms which form and transform this policy domain. To understand the state of a policy domain and its dynamics over time an institutional approach is taken. Two concepts in political science, ‘policy arrangements’ and ‘supranational governance’ are combined and used as a framework to analyse the European transport policy domain. This analysis describes the development of several elements: organisations, rules, the transnational society, power, resources, and the central transport discourse. It demonstrates that all of these elements have developed from an intergovernmental setting towards a more supranational one. This development was slow in the first decennia when European transport policy was rather passive, but it picked up speed in the 1980s and 1990s. In the pivotal year of 1985, pressure from the transnational society resulted in a rapid change of the rules, the resources and the discourse.  相似文献   

12.
地表过程研究进展与趋势   总被引：4，自引：1，他引：3  
地表过程复杂多样、涉及广泛。针对当前地表过程研究现状,从地球系统科学和全球变化的视角讨论了与地表过程相关的一些概念及研究内涵。在分析单要素地表过程和多要素地表过程的基础上,从研究内容的综合性、多国合作的国际性、针对区域突出问题的区域性、以过程变化为核心的动态性及研究方法的多样性等方面论述了地表过程研究的特点,总结性地给出了国内外研究的总体趋势。在上述分析基础上,进一步从国际科学发展趋势、国家需要和信息、技术等方面分析了中国地表过程研究所面临的机遇;从多学科交叉、自然与人文过程的定量与有机耦合等方面讨论了地表过程研究所面临的挑战。  相似文献   

13.
运用差分GPS动态获取高精度土地资源变化数据的新技术   总被引：9，自引：0，他引：9  
由于经济的飞速发展,许多耕地被占用变为非农业用地。土地管理部门需要及时准确地掌握城镇和农村用地的变化格局,为耕地保护政策的制定提供依据。但传统的土地变更测量方法存在难于准确获取变化边界坐标,成图困难且周期长、人为操作随意性大等不足。在分析各种GPS差分技术的基础上提出了运用移动差分GPS技术获取土地利用变化信息的新方法。作为国家“九·五”攻关项目的研究内容,该方法在包头市郊区县进行了实验,结果证明与传统测量方法相比,具有快速、准确,操作简便,GPS数据输入GIS,可以快速成图等优点。  相似文献   

14.
Whither stratigraphy?   总被引：2，自引：0，他引：2  
There have been three revolutions in sedimentary geology. The first two began in the 1960s, consisting of the development of process-response sedimentary models and the application of plate-tectonic concepts to large-scale aspects of basin analysis. The third revolution, that of sequence stratigraphy, began in the late 1970s and helped to draw together the main results of the first two: the knowledge of autogenic processes learned through facies analysis, and the understanding of tectonism implicit in the unravelling of regional plate kinematics. Developments in the use of seismic-reflection data and the evaluation of a hypothesis of global eustasy provided considerable stimulation for stratigraphic research.Current developments in the field of sequence stratigraphy are focusing on three areas. (1) Elaboration of the sequence-architecture models for various configurations of depositional environment and sea-level history. (2) Exploration of various mechanisms for sequence generation, especially tectonism and orbital forcing. (3) Attempts to improve the level of precision in stratigraphic correlation and to refine the geological time scale, as a means to test the model of global eustasy.The growth in the power of computers and our knowledge of physical and chemical processes has led to the evolution of an entirely new way of evaluating earth history, termed quantitative dynamic stratigraphy. Mathematical modelling and numerical simulation of complex earth processes are now possible, and require the collection and integration of a wide array of quantitative and qualitative data sets. Applications include the study of the geodynamic evolution of sedimentary basins, modelling of stratigraphic sequences and global climates, studies of Milankovitch cycles (cyclostratigraphy) and simulation of fluid flow through porous media. The Global Sedimentary Geology Program has brought many of these areas of study together in multidisciplinary, global-scale studies of the sedimentary history of the earth. The results of these studies have wide application to many problems of importance to the human condition, including the past history of global climate change and other environmental concerns. The study of stratigraphy is at the centre of the new view of the earth, termed earth-systems science, which views earth as an ‘organic’ interaction between the lithosphere, biosphere, hydrosphere, and atmosphere.  相似文献   

15.
Land use and land cover change is an important driver of global change (Turner et al., 1993). It is recognized that land use change has important consequences for global and regional climates, the global biogeochemical cycles such as carbon, nitrogen, and water, biodiversity, etc. Nevertheless, there have been relatively few comprehensive studies of global, long-term historical changes in land cover due to land use. In this paper, we review the development of global scale data sets of land use and land cover change. Furthermore, we assess the differences between two recently developed global data sets of historical land cover change due to land use. Based on historical statistical inventories (e.g. census data, tax records, land surveys, historical geography estimates, etc) and applying different spatial analysis techniques, changes in agricultural land cover (croplands, pastures) were reconstructed for the last 300 years. The two data sets indicate that cropland areas expanded from 3–4 million km2 in 1700 to 15–18 million km2 in 1990 (mostly at the expense of forests), while grazing land area expanded from 5 million km2 in 1700 to 31 million km2 in 1990 (mostly at the expense of natural grasslands). The data sets disagree most over Latin America and Oceania, and agree best over North America. Major differences in the two data sets can be explained by the use of a fractional versus Boolean approach, different modelling assumptions, and inventory data sets.  相似文献   

16.
根据当前土地利用变化分析及预测研究现状,提出了以焦作市高新区1990~2005年土地利用空间数据资料为试验数据,对系统图形与属性数据建库、模型库及其同G IS的集成土地利用变化预测系统并且进行了初步设计及实现。利用VC 和MapObjects编程实现地图查询与分析、指标测算、模型构建及检验等功能,为用地变化预测及研究者们实现预测模型的构建、属性数据的统计运算、图形数据的处理提供功能集成的应用型G IS平台,该系统也为合理利用土地提供更为科学和准确的决策。  相似文献   

17.
In many countries worldwide, similar state policies on land management have been implemented as a response to deforestation in mountainous areas. So far, few studies have examined to which extent these policies have actually contributed to reforestation. This is the focus of our analysis, based on a case study in Vietnam. Because land access and land use were traditionally governed by common rules, we examine land use changes from an institutional perspective. We use the Institutional Analysis and Development (IAD) framework, coupled with an historical perspective and the analysis of actors’ perception and dominant narratives on land management and forests. Results show that national policies significantly interfered with local factors, leading to a complex course of decision-making and action. Substantial reforestation in the area was not a response by farmers to policy incentives but rather the unexpected outcome of the disruption of local institutions by these policies. We argue that, because national interventions have relied on false or exaggerated narratives and beliefs, their implementation is in conflict with the local reality in upland areas, leading to unpredictable and locally dependent outcomes. We defend hence the need for local level studies and also recommend considering local institutions for land use change analysis in contexts where land use systems are characterised by a high degree of human interaction.  相似文献   

18.
虚拟土战略与土地资源可持续利用的社会化管理   总被引：26，自引：0，他引：26  
土地资源紧缺是威胁世界食物安全的主要限制因素之一, 土地资源可持续利用是区域生态经济系统经济增长和社会发展的关键. 类似于国内已经开展的虚拟水和虚拟水战略概念及相关研究, 首次提出"虚拟土"和"虚拟土战略"新概念, 分析了土地资源管理不同管理阶段及其相关问题. 结合当前国家耕地总量平衡、区域粮食安全问题以及土地资源利用中出现的一些新情况, 从土地资源的社会属性出发, 实证分析了土地生产能力与社会适应性能力的关系, 提出了基于虚拟土概念及虚拟土战略下区域土地资源可持续利用的分析框架. 最后提出了当前我国土地利用中解决区域粮食安全的一些新思路. 建议: 在保证国家粮食基本自足基础上, 实行区域耕地总量弹性平衡政策; 成立专业性土地银行, 加快创新土地使用权流转机制; 强化土地使用权拍卖机制, 提高市场配置土地资源的透明度; 实施虚拟土战略举措, 构建新的土地可持续发展模式, 加强开展虚拟土战略相关理论及其对策的研究工作.  相似文献   

19.
We describe empirical results from a multi-disciplinary project that support modeling complex processes of land-use and land-cover change in exurban parts of Southeastern Michigan. Based on two different conceptual models, one describing the evolution of urban form as a consequence of residential preferences and the other describing land-cover changes in an exurban township as a consequence of residential preferences, local policies, and a diversity of development types, we describe a variety of empirical data collected to support the mechanisms that we encoded in computational agent-based models. We used multiple methods, including social surveys, remote sensing, and statistical analysis of spatial data, to collect data that could be used to validate the structure of our models, calibrate their specific parameters, and evaluate their output. The data were used to investigate this system in the context of several themes from complexity science, including have (a) macro-level patterns; (b) autonomous decision making entities (i.e., agents); (c) heterogeneity among those entities; (d) social and spatial interactions that operate across multiple scales and (e) nonlinear feedback mechanisms. The results point to the importance of collecting data on agents and their interactions when producing agent-based models, the general validity of our conceptual models, and some changes that we needed to make to these models following data analysis. The calibrated models have been and are being used to evaluate landscape dynamics and the effects of various policy interventions on urban land-cover patterns.  相似文献   

20.
研究大型矿业基地土地利用动态变化过程可间接评估矿产开发对区域生态环境的影响。采用2005年、2010年和2015年3期SPOT-5和GF-2卫星影像数据,通过人工目视解译与计算机自动提取相结合的手段,提取宁东煤炭基地土地利用信息,并收集2000年土地利用遥感解译信息,构建土地利用程度综合指数、动态度等,定量研究宁东煤炭开发引起的土地利用变化,结合经济社会发展指标,构建驱动土地利用变化的定量评价体系,分析了宁东煤炭基地土地利用格局变化的驱动因素。结果表明,2000—2015年宁东煤炭基地一直处于土地持续开发利用阶段,主要表现为草地、林地及耕地向工矿用地为主的建设用地转变,但土地利用程度综合指数的增幅有所下降,表明基地建设逐渐进入稳定期,土地利用压力趋于下降;主成分分析表明,人类活动驱动着宁东土地利用格局的变化,主要有封山禁牧政策、产业化和规模化、人口增长、城镇化等因素。该研究结果可为宁东煤炭基地未来生态环境保护提供科学依据。  相似文献   

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