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1.
Data on land use change in the UK and its constituent nations is variable in scope and quality, but has improved in recent years. It shows that the popular image of cities spreading across the countryside is a false one. In fact most new housing is built within existing settlements or in small rural developments, whilst more crop and grazing land has been turned over to woodland in the past 25 years than into housing. It also shows that market forces, taxes and subsidies have a rapid effect on land use decisions by developers, farmers and others, for example on what type of housing to build, what crops to grow and whether to turn farmland into woodland.  相似文献   

2.
《Land use policy》1987,4(2):96-101
In the mid-1950s a team of research workers from Durham University's geography department carried out a detailed agricultural land use survey of the Maltese Islands. Since then Malta has gained political independence, although the economic distortions associated with the colonial period have not yet come to an end. This article looks at Maltese agricultural land use and reassesses it against the background of changes which have occurred in Malta 's political and economic status.  相似文献   

3.
Household food security among smallholder farmers is sensitive to a variable and changing climate, requiring farmers in the Gamo Highlands of Ethiopia to adopt new land management practices to improve food security. Agricultural land in the Gamo Highlands is highly fragmented. The extent to which land fragmentation (LF) moderates the food security effects of sustainable land management (SLM) practices is unknown. This study used probit and Poisson models to explain this relationship. The study found that food insecurity was severe during the food shortfall season. LF provides more potential opportunities for improving food security than challenges. Furthermore, SLM practices had both positive and negative effects on food security and their effects were conditioned by the magnitude of LF. Reducing severe LF through the assembly of small parcels into larger heterogeneous plot clusters could enhance food security by exploiting synergies between adaptation practices and LF.  相似文献   

4.
Land use and demographic change: results from fast-growth counties   总被引:1,自引:0,他引:1  
The authors analyze and compare two data sets on land-use change in U.S. counties with rapidly growing populations for the period from 1960 to the early 1980s. The results show that "the net effect of changing household numbers, household characteristics, and economic constraints on demand for land is likely to mean less conversion of land for urban uses in the future. Our studies showed that marginal urban land consumption remained nearly constant between 1960 and the early 1980s."  相似文献   

5.
以河南省为研究区,对不同年份的土地利用数据进行分类系统整合,在此基础上,对河南省1996~2009年土地利用类型进行了对比分析,分析得出耕地、城镇村及工矿用地、林地、交通运输用地面积在增加,园地、草地、水域及水利设施用地、其它土地面积在减少,在各类土地类型转换中,林地是变化最为激烈的土地利用类型,其次是其它土地,变化最稳定的地类是交通运输用地,其次是耕地。  相似文献   

6.
Relative agricultural productivity shocks emerging from climate change will alter regional cropland use. Land allocations are sensitive to crop profits that in turn depend on yield effects induced by changes in climate and technology. We develop and apply an integrated framework to assess the impact of climate change on agricultural productivity and land use for the U.S. Northern Great Plains. Crop-specific yield–weather models reveal crop comparative advantage due to differential yield impacts of weather across the region's major crops, that is, alfalfa, wheat, soybeans, and maize. We define crop profits as a function of the weather-driven yields, which are then used to model land use allocation decisions. This ultimately allows us to simulate the impact of climate change under the RCP4.5 emissions scenario on land allocated to the region's major crops as well as to grass/pasture. Upon removing the trends effects in yields, climate change is projected to lower yields by 33–64% over 2031–2055 relative to 1981–2005, with soybean being the least and alfalfa the most affected crops. Yield projections applied to the land use model at present-day input costs and output prices reveals that Dakotas’ grass acreage will increase by up to 23%, displacing croplands. Wheat acreage is expected to increase by up to 54% in select southeastern counties of North Dakota and South Dakota, where maize/soy acreage had increased by up to 58% during 1995–2016.  相似文献   

7.
This paper evaluates the role of trade liberalization and agricultural intensification in mitigating climate change cause and effects on land use and emissions using a computable general equilibrium model. Our results indicate that cropland expansion triggered by climate-induced crop productivity changes results in deforestation and increases emissions in South Asia and globally. Global full trade liberalization on all goods is the optimum policy for South Asia despite significant global deforestation, but for the world, unilateral partial trade liberalization on all goods is a more appropriate policy while ensuring a considerable emissions reduction for South Asia. These results indicate that mitigation responses to climate change are location specific and no one trade policy is suitable at the regional and global levels. Lastly, agricultural intensification by improving productivity growth is the best strategy in land-based emissions mitigation, thereby avoiding the transformation of forest and pasture lands for agricultural cultivation both at regional and global levels.  相似文献   

8.
Climatic and land use change are amongst the greatest global environmental pressures resulting from anthropogenic activities. Both significantly influence the provision of crucial ecosystem services, such as carbon sequestration, water flow regulation, and food and fibre production, at a variety of scales. The aim of this study is to provide spatially explicit information at a national level on climate and land use change impacts in order to assess changes in the provision of ecosystem services. This work provides a qualitative and quantitative analysis of the impacts on selected ecosystem services (carbon sequestration, food production and soil erosion) in the agricultural sector of the Czech Republic. This assessment shows that, historical land use trends and land use under projected climate scenarios display some shared spatial patterns. Specifically, these factors both lead to a significant decrease of arable land in the border fringes of the Czech Republic, which is to some extent replaced by grasslands, in turn affecting the provision of ecosystem services. Moreover, this assessment contributes to a useful method for integrating spatially explicit land use and climate change analysis that can be applied to other sectors or transition countries elsewhere.  相似文献   

9.
The concept of land use transition highlights that land use change is non-linear and is associated with other societal and biophysical system changes. A transition in land use is not a fixed pattern, nor is it deterministic. Land use transitions can be caused by negative socio-ecological feedbacks that arise from a depletion of key resources or from socio-economic change and innovation that take place rather independently from the ecological system. Here, we explore whether the sources of land use transitions are mostly endogenous socio-ecological forces or exogenous socio-economic factors. We first review a few generic pathways of forest transition as identified in national case studies, and evaluate the varying ecological quality of expanding forests associated with these pathways. We then discuss possible explanatory frameworks of land use transitions. We use the case of the recent forest transition in Vietnam as an illustration. Socio-ecological feedbacks seem to better explain a slowing down of deforestation and stabilization of forest cover, while exogenous socio-economic factors better account for reforestation. We conclude by discussing the prospects of accelerating land use transitions in tropical forest countries.  相似文献   

10.
基于CA-Markov模型的大连市旅顺区土地利用变化及预测研究   总被引:1,自引:0,他引:1  
实时监测土地利用及其变化(LUCC)的状况对于经济增长、社会进步、环境保护以及生态文明建设具有重要的意义。本文基于IDRISI软件中的CA-Markov模型,分析了大连市旅顺区1994年-2014年的土地利用变化,同时预测了2024年的土地利用状况。结果表明:旅顺自1994年来,建筑用地面积逐年增加,并主要集中在中南部和西部沿海地区,与此同时,耕地面积也逐年增加,但由原来的西部逐渐演退至北部区域的丘陵地带,林地面积逐步萎缩,面积大幅下降,其主要被开垦为耕地或建筑用地,在本区域中南、西南部,林地大多直接转变为建筑用地或先转变为耕地再转变为建筑用地,而北部则主要转变成了耕地和相对较小的居民点,水域(湖泊、河流)的面积逐年减少,湖泊、水库面积萎缩,随着城镇化的加快和人口数量的不断增加;由于不断地城市用地开发和林地的砍伐以及耕地的弃用等综合因素导致,未利用地减少。总体上,旅顺的土地利用变化由于经济建设的力度不断加大,人工自然景观用地越来越多,生态安全压力不断增大,未来十年间,旅顺土地利用将持续20年来的趋势,但变化速度放缓。  相似文献   

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12.
研究目的:分析英国土地规划政策对房地产市场供给的影响。研究方法:应用政策分析方法总结英国土地规划政策特点,特别是分析规划许可证制度对房地产供给的影响。研究结果:(1)英国政府通过土地规划政策对房地产市场进行间接调控,能够有效控制各类房地产产品的供应数量。但是调控在市场上升阶段存在较强的滞后效应;在市场低迷时,调整的功效甚微。(2)英国政府通过土地规划许可证的签发,要求房地产开发商负担起建设保障性住房的任务,这一政策保证了保障性住房的质量和数量,促进低收入人群融入社区,有利于社会和谐发展,但是房地产开发商的成本被推高,商品房供给减少,最终导致商品房价格偏高。研究结论:中央和地方政府可以灵活利用土地规划政策对市场进行调控,但是政府行为通常会带来意想不到的“成本”,应随时调整政策,保证政策有效实施的情况下降低“计划外”成本。  相似文献   

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15.
The livelihoods of resource-dependent peoples are vulnerable to climate variability. This study focuses on how local climate adaptations, which have been sustained through long-term interactions with local ecologies, have changed in the face of the challenges caused by climate change and policy interventions. Case studies were conducted in two agro-pastoral counties of northern China, a region that confronts frequent drought and that has experienced extensive institutional changes over recent decades. Based on the exploration of four adaptation strategies, the field results show that both counties have experienced an acceleration of livelihood diversification, an increase in storage and market exchanges, and a dramatic reduction in previously common pooling. The findings reveal that these adaptations are not a direct result of coping with climate risks but rather are indicative of livelihood strategies that result from the combined impacts of institutional, socioeconomic and climatic changes. Current institutional arrangements have negative impacts on local climate adaptations. This is particularly true for those with limited livelihood options, and such arrangements may therefore foster an increase in inequality with regard to household adaptive capacities over the long term. Therefore, this study recommends flexible policies that facilitate local arrangements rather than the current one-for-all policy.  相似文献   

16.
介绍了马鞍山市的概况、土地利用现状及土地利用结构、空间布局、城市用地、土地开发整理、重大生态建设工程对生态环境的影响;提出了促进该市生态环境建设的一些政策和管理措施。  相似文献   

17.
《Land use policy》1986,3(4):247-259
With high and accelerating population growth and with low and declining efficiency in the use of resources, Africa is currently facing a long-term declining trend. Since agriculture accounted for 41% of the GDP of Africa in 1982, formulation and implementation of efficient land use policies are prerequisites if the long-term adverse trend is to be reversed.  相似文献   

18.
The author pinpoints India's current land and water use problems. Various solutions are suggested taking into account the demands of the expanding population and the importance of agricultural land to India's development. India's climatic variations and the ways in which they affect land and water supplies and planning, are covered in detail. The many serious difficulties which the two natural resources face and which the planners must overcome if land and water are to be put to optimal use, are outlined separately, yet the interrelations between land and water and the need to develop them are also stressed.  相似文献   

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20.
The efficiency of potential climate change mitigation is predicated on future costs and benefits and thus heavily influenced by the discount scheme. Dual discounting involves discounting carbon and monetary values differently; stand level modeling efforts show that it improves the profitability of afforestation projects. However, these stand level results may not hold across other age classes and stocking levels. Using a partial, spatial equilibrium model of the Norwegian forest sector, we analyze the impacts of a dual discounting scheme on climate change mitigation efforts. Dual discounting results in less mitigation efforts in the first decades but substantially higher long-term mitigation efforts.  相似文献   

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