干旱荒漠区土地利用变化对地表温度的影响

该文以Landsat TM 遥感影像为主要数据源,获取了宁夏中卫市沙坡头区1992年和2007年的土地利用信息;利用单窗算法反演了对应时期该区域的地表温度（LST）;据此分析了土地利用变化与地表温度变化之间的关系。结果显示：1）不同利用方式的土地的LST有显著差异,流动沙地的LST最高,其次是固沙用地、草原化荒漠等;2）过去15 a间,研究区内最为明显的土地利用变化方向是“草原化荒漠转变为农田”和“流动沙地转变为固沙用地”;3）“草原化荒漠转变为可灌溉农田”会导致LST明显下降,“草原化荒漠转变为压砂田”     

Multilevel modelling of land use from field to village level in the Philippines

In land use research regression techniques are a widely used approach to explore datasets and to test hypotheses between land use variables and socio-economic, institutional and environmental variables. Within land use science researchers have argued the importance of scale and levels. Nevertheless, the incorporation of multiple scales and levels and their interactions in one analysis is often lacking. Ignoring the hierarchical data structure originating from scale effects and levels, may lead to erroneous conclusions due to invalid specification of the regression model. The objective of this paper is to apply a multilevel analysis to construct a predictive statistical model for the occurrence of land use. Multilevel modelling is a statistically sound methodology for the analysis of hierarchically structured data with regression models that explicitly takes variability at different levels into account. For a land use study in the Philippines multilevel models are presented for two land use types that incorporate the field, household and village level. The value of multilevel modelling for land use studies and the implications of multilevel modelling for data collection will be discussed. The results show that explanatory variables can account for group level variability, but in most cases a multilevel approach is necessary to construct a sound regression model. Although land use studies often show clear hierarchical structures, it is not always possible to use a multilevel approach due to the structure of most land use datasets and due to data quality. Potentially, multilevel models can address many important land use issues involving scales and levels. Therefore, it is important in land use change research to formulate hypotheses that explicitly take scale and levels into account and then collect the appropriate data to answer these questions with approaches such as multilevel analysis.     

Agrarian policies for sustainable land use: bio-economic modelling to assess the effectiveness of policy instruments

This article presents a bio-economic modelling approach for the assessment of the effectiveness of different agrarian policies to improve farm household income and soil fertility. Farm household decisions on allocation of land, labour and capital resources for crop and production technique choice are simulated, taking into account resource availability, household objectives and prevailing market conditions. The modelling framework relies on a combination of three procedures: (1) farm household modelling, (2) linear programming, and (3) partial equilibrium analysis. These procedures are applied to evaluate the impact at farm household and regional level of technology improvement and a variety of policy instruments: improvement of infrastructure, price support, land policy and credit schemes. Regional aggregation allows prices to be determined endogenously on regional markets. The approach is applied to the Cercle de Koutiala in Mali, for which selected results are given as an example. Results indicate that technology alone cannot sufficiently induce farmers to adopt sustainable production systems. Additional economic incentives are necessary to foster technological change.     

Factors driving land use change: Effects on watershed functions in a coffee agroforestry system in Lampung,Sumatra

Forest cover in Sumberjaya declined from 60% to 10% over the past three decades; current land uses are a mosaic of smallholder coffee fields on slopes, and rice paddies and vegetables in the valleys. While deforestation was continuing at the forest frontier, farmers were already ‘re-treeing’ the landscape and many monoculture coffee gardens were gradually transformed into mixed systems with shade trees. In this case study we illustrate that the factors driving deforestation were strong, interconnected and generally outside the forestry domain. The current agroforestry landscape generates a significantly higher discharge than in the past, allowing a hydropower dam to revise its power-production targets upwards. One of the main reasons given to justify the eviction of farmers in the watershed, based on claims that the past land use change would negatively affect the discharge and the dam’s power generation, proved wrong. In this area, various myths about watershed functions – already dismissed in other parts of the world – still dominate the thinking of many foresters and policymakers; this paper illustrates how and why this situation came about.     

Modeling the impact of global change on regional agricultural land use through an activity-based non-linear programming approach

Assessing the impact of climate change on agriculture is a new challenge for quantitative model-based policy analysis. The impact of climate change will vary strongly across regions depending on pre-existing climatic, agronomic, and political conditions. Most of the present modeling approaches, which aim to analyze the impact of global change on agriculture, deliver aggregated results both with regard to content and spatial resolution. To deliver results with a higher spatial resolution and to produce a more detailed picture of agricultural production, the county-based agro-economic model known as ACRE-Danube was developed. The German and Austrian part of the Upper Danube basin, a study area with great diversity in agricultural landscapes and climatic conditions, was chosen for study. For the analysis, two scenarios of climatic and socio-economic change were derived. The first and more economically and globally oriented scenario, termed “Full Liberalization,” included significant temperature increases. The second and more environmentally and regionally oriented “Full Protection” scenario included a moderate temperature increase. Both scenarios produce different results regarding agricultural income and land use. While the developments in the Full Protection scenario are small, the Full Liberalization scenario yields extreme regional changes in agricultural income, an increase in cereal production and extensive grassland farming.     

Multi-scale analysis of agricultural development: A modelling approach for Ilocos Norte,Philippines

Decisions and policies that have implications on allocation of resources are made at different levels. Goals at different scales may be conflicting and decisions at one scale have consequences for those at other scales. Performing analyses at more than one scale is, therefore necessary in analysing future options for resource use. This paper illustrates the use of a multi-scale method enabling assessment of multi-purpose natural resource management options. Three examples of analyses that it allows are presented for Ilocos Norte province in the Philippines, at the farm household, municipal (Batac municipality) and provincial levels. Results show that: (1) Differences in resource endowments of farm households strongly affect the potential adoption rates of five well-defined alternative technologies. (2) Limited markets, inadequate infrastructure and resource endowments of farm households have large effects on resource use and goal achievement in the municipality. Not including these factors in a resource use analysis results in a so-called aggregation bias. As these are significant, ignoring them may result in misleading simulation results and policy conclusions. The aggregation bias resulting from assuming spatially fixed input and output prices is significant for Batac, which has poor farm-to-market roads. This suggests large potential benefits from improving infrastructure. The factors investigated suggest that aggregate income in the municipality is most strongly affected by the size of the market for some vegetables. (3) The differences in resource allocations resulting from prioritizing objectives at different levels reveal potential conflicts. The municipal income was highest with crops which pose more risk to farmers; our farm household analysis shows that farmers tend not to select too much of these crops. Similarly, the provincial income is highest when resources in the province are allocated such that more of the staple crop rice and less of the highly profitable cash crops are cultivated in Batac, resulting in lower income for the municipality.     

Land use change patterns and livelihood dynamics on the slopes of Mt. Kilimanjaro,Tanzania

This study is about changes in land use and interactions of land use change and livelihoods in the Chagga farming system on the slopes of Mt. Kilimanjaro, Tanzania. An aerial photo interpretation and fragmentation analysis of the years 1961, 1982 and 2000 was conducted covering approximately the Kirua Vunjo Division, a transect of 152 km² from the forest reserve edge to the plains. Earlier changes were traced from literature review. The results show the expansion of cultivation to more marginal land down the slope, the disappearance and extreme fragmentation of bush land and appearance and expansion of settlements. The home garden area has experienced some specific internal change, but has not expanded down the slope. In the 1960s there were small open fields and patches of grazing lands amongst home gardens. In the 1980s the area was more uniformly covered by homegardens. Since then it has become patchy again as new homesteads have been built on subdivided farms and more food is produced on the higher slopes. Population pressure and the ensuing expansion of agriculture to more marginal land, intensification of the homegarden system, together with climate changes affecting the water supplies, have caused changes in farmers’ livelihoods. As land scarcity now hinders expansion of agriculture, farm size has seriously decreased, common resources have become scarce, and prices of coffee in the world market remain low, farmers are trying to intensify and diversify their farm production. Local initiative is leading to change, but the locally conceived alternatives are too few and lack integrated approaches of technical agricultural research, economic analysis, and policy studies and reforms. Non-agricultural activities and paid employment are becoming increasingly important. However, due to considerable entry barriers to remunerable off-farm jobs, not all households enjoy equal access to attractive non-farm opportunities. The future welfare of the area will depend on increasing the marketable knowledge and skills of the population that will enable it to become integrated in the economy of the region and the country.     

Logistic modelling to identify and monitor local land management systems

In the wake of sustainable development, measurable indicators are needed to monitor land resources management. Aerial photograph interpretation, participatory research methods and logistic modelling were combined to establish indicators and to investigate their relationship with local land management systems. Land tenure and customary laws explained the differences in field characteristics at Ikem (southeastern Nigeria). A binary followed by an ordinal logistic model quantified the relationship between field characteristics and local land management. The odds for private land management increased with 102% per 100 m² decrease in field size and with 128% per unit increase in palm tree density. For communal land management, fallow periods were longer with increasing non-palm tree densities and field sizes; odds increased with 76 and 31%, respectively. Field size, total tree density and palm tree density are important indicators to monitor local land management.     

Farmers’ management strategies and land use in an agropastoral landscape: roquefort cheese production rules as a driver of change

Cultural landscapes in Europe provide a wide range of food products and fulfil social and environmental functions. In order to maintain agricultural practices that contribute to maintaining the biological and cultural value of semi-natural landscapes, agri-environmental schemes are being implemented in many western European countries. In the mountains of southern Europe a major issue is the encroachment of shrubs and trees through natural forest succession following agro-pastoral extensification.In this paper we analyse trends in land use strategies of sheep breeders in response to milk pricing and in relation to various within-farm mechanisms. We show that changes in production rules within the Roquefort cheese protected geographical indication have caused farmers to develop an alternative land use strategy. In this alternative model, farmers now consider rangelands as a valuable resource. By increasing the use of rangelands for sheep grazing and alimentation, this new strategy provides a more effective control of shrub and tree encroachment.We suggest that this involuntary consequence of production and market decisions has been at least as important as agri-environmental schemes in leading ewes’ milk producers to make changes in their land use strategy.     

提高土地利用——土地覆盖遥感分类精度方法研究综述

本文总结了国内外提高土地利用-土地覆盖遥感分类精度的若干方法：可提高精度的大气校正方法、多源信息融合方法、人工智能分类方法等。并对其中部分方法进行了优缺点评价。     

提高土地利用——土地覆盖遥感分类精度方法研究综述

本文总结了国内外提高土地利用-土地覆盖遥感分类精度的若干方法:可提高精度的大气校正方法、多源信息融合方法、人工智能分类方法等.并对其中部分方法进行了优缺点评价.     

Spatial distribution of grassland productivity and land use in Europe

Grasslands are an important land use in Europe with essential functions for feed and ecosystem service supply. Impact assessment modelling of European agriculture and the environment needs to consider grasslands and requires spatially explicit information on grassland distribution and productivity, which is not available.     

唐县未利用地转型的生态风险变化研究

开展县域生态风险评价可为县域生态风险防控与生态环境保护提供科学依据。以河北省唐县为研究区域,基于2000年、2007年和2018年3期土地利用数据,从风险源、风险受体暴露度、风险效应三个方面构建生态风险评价模型,对唐县未利用地转型前后的生态风险及其时空变化、影响因素进行分析。研究结果表明:2000—2018年,提供生态空间的未利用地面积显著减少,提供生态空间的草地、林地面积及提供生产空间的耕地面积和提供生活空间的城镇和居民点面积显著增加,土地利用类型变化使得生态空间向生活空间和生产空间转化。未利用地转型后,研究区生态风险略有提高,生态风险值由2000年的0.079增加到2018年的0.107,低风险区面积比例降低,中高风险区面积比例增加,总体处于较低风险水平。与生态风险相关性较大的指标有土地利用指数、建设用地比例、农田面源压力、人口压力,应合理规划开发未利用地,注意从风险源头进行生态管控,加强生态建设。研究结果对于区域未来土地利用与管控及保持生态平衡具有重要意义。     

The efficient use of labour,land and energy in agriculture

Fossil energy-using agricultural systems may be defined as systems transferring tradeable energy resources in tradeable agricultural products by means of untradeable labour and untradeable land. The substitution of tradeable energy and untradeable labour is considered and it is shown that the energy efficiency of agricultural production systems increases with increasing control of production and increasing yields.The main conclusion is that agriculture may contribute to a more sensible use of energy by developing in a direction where as high yields as possible per hectare are obtained from as small an area as possible.     

喀斯特山区贫困乡村土地利用的地形梯度特征

为厘清喀斯特地区小尺度土地利用在地形梯度的特征。基于0.5 m分辨率的Pleiades遥感影像和DEM数据,在ArcGIS技术支持下,采用人工目视解译方法,进行土地利用分类和地形位指数计算,并利用Fragstats 4.2软件,从景观生态学视角,分析4种不同喀斯特地貌的典型乡镇土地利用的地形梯度特征。研究发现:4个不同地貌乡镇的斑块数量(NP)和斑块形状指数(LSI)变化在地形位梯度上存在相似性,而与斑块所占景观面积(PLAND)变化规律有明显不同。斑块水平上各指标变化在4个地貌乡镇之间存在一定差异。随着地形位指数增加,4个乡镇的聚集度(AI)和蔓延度(CONTAG)整体上呈增加趋势,而4个地貌乡镇的香浓多样性指数(SHDI)和连接度(COHENSION)变化存在差异。不同地貌的土地利用结构的差异是形成不同喀斯特地貌贫困乡村土地利用梯度特征的重要因素。     

Modelling multiple objectives of land use for sustainable development

Sustainability is a human-centred concept that comprises multiple aspects and objectives of different interest groups. Sustainable development is not readily measurable, except as a compromise between different parts of society, of which some may try to represent future generations of mankind. To determine a sustainable development path in the relationship between agriculture and its natural environment, a profound knowledge of this complex system and its behaviour under different socio-economic conditions is necessary. We present a modelling system which consists of a set of hierarchically linked modules. These modules describe production activities in a way that allows an economic and ecological analysis of these techniques. The heart of the modelling system is a multiple goal linear programming model, which is generated by data base modules. Simulation of single farm models as well as regional models based on simultaneously optimised farm types is possible. The modelling system appears to be a highly flexible tool with respect to the number and type of farms, sites and production techniques. Environmental objectives can easily be included and different levels of goal achievement can be simulated. It is well suited for single farm analysis as well as for regional models, for static as well as dynamic approaches. It allows rapid adoption of the model and rapid calculation of scenarios. Therefore, it is suited for use in interactive environments with users which are interested in repeated runs with little changes in the goal function, prices, subsidies or technical coefficients. The results can be used for policy decisions as well as the strategic planning of individual farmers. Applications of the modelling system will be presented in following papers. In this paper the kind of information the model can generate and the circumstances of their usage are shown. ©     

湖南桃源县土地利用动态变化研究

研究土地利用/土地覆盖动态变化是研究全球变化的核心。文章以地理信息系统为研究手段,利用重心模型和时间序列动态模型对桃源县2000年～2009年的土地利用变化动态度及其重心进行了分析,得出耕地正在向东北方向扩展,园地向东南方向扩展,林地向东部偏南扩展,建设用地向西北方向扩展的结论,以期对桃源县的土地利用提供指导作用。     

Exploratory land use studies and their role in strategic policy making

To support the different phases of a policy making process aimed at changing land use, distinct types of land use studies are required. This paper focuses on exploratory land use studies and their role in the phase of formulating strategic policy objectives. Exploratory land use studies contribute to a transparent discussion on policy objectives by showing ultimate technical possibilities and consequences of imposing different priorities to agro-technical, food security, socio-economic and environmental objectives. A methodology is presented in which science-driven technical information is confronted with value-driven objectives under given values of exogenous variables (e.g. regarding population growth and requirements for agricultural produce). Land use scenarios are generated showing consequences of different priorities for objectives by using natural resources and technical possibilities in different ways. Applications of such an approach are given for the global, regional and farm level, each addressing specific questions and target groups. The paper focuses on the type of results these studies produce and their role in the societal and political debate on strategic land use policy and planning. It is concluded that if exploratory land use studies are carried out in true interaction with target groups, they may well contribute to the debate and learning on sustainable land use options and a purposeful identification of effective policy instruments in a next phase of the policy making process.     

北京山区耕地质量变化及未来趋势模拟

准确把握区域耕地质量现状、空间分布以及未来变化,对实现耕地保护由数量平衡与管理向数量-质量综合平衡与管理具有重要意义。应用GIS空间分析与模拟技术,在对北京山区耕地质量进行定量评价的基础上,对山区不同地域层次上的耕地质量变化及未来趋势进行了分析。研究结果发现,1993－2004年北京山区以及各地貌类型区域耕地质量处于总体提高态势,耕地质量的提高主要是耕地布局优化的结果。2004－2015年,北京山区耕地总体质量将继续提高,但总体幅度有所减小;同时,不同区域耕地质量变化出现分异,山区和半山区耕地质量仍然不断     

Regional land use analysis: the development of operational tools

Regional land use analysis plays a key role in the analysis of agricultural policies. However, few operational tools for regional land use analysis are available. Current developments in regional land use analysis are rather ad hoc. More generic methodologies are required to effectively answer questions by policy makers. The analysis may require methods to explore, project and predict agricultural land use. An all-encompassing methodology seems unrealistic. A toolbox for regional land use analysis is proposed. The tools (including, e.g. database management systems, GIS and economic models) can be linked in such a way that they can carry out the analysis required for the specific conditions of stakeholders. To facilitate linkages between the different tools, data standards need to be developed for both bio-physical as well as economic data. Discussions with stakeholders in an early phase of the analysis may set priorities and determine the selection of tools. Results of the analysis need to be presented in such a way that they are appealing to the stakeholders. Only then can they be transferred effectively. The general framework is illustrated with a methodology for regional land use analysis in terms of economic and environmental trade-offs.