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1.
The role of land tenure in agricultural development has been a subject of intensive research, particularly within the context of land and agrarian reform. The complexity of the world's major land tenure systems is well recognized and no attempt is made here to go beyond an overview as this paper limits itself to the impact of land tenure on land use in low income situations. Present land use is determined by a host of factors, of a physical/biological and socioeconomic nature. In applying land evaluation, the question it is necessary to ask is to what extent, when and where land tenure conditions act as a considerable constraining factor impeding a more optimal use of land resources. Even in what used to be low-population density areas (such as Sub-Saharan Africa) it appears that the frontier phase is becoming exhausted and the intensification of agriculture proceeds; it becomes imperative to examine land tenure in relation to land use implications. It is shown that so far a multi-disciplinary approach has often been lacking in treating land tenure and related issues.  相似文献   

2.
Wei Yaping  Zhao Min   《Land use policy》2009,26(4):1031-1045
Rather than a bad case of urban sprawl, the physical expansion of China's megacities may be viewed as a combination of ‘urban spill over’ and ‘local urban sprawl’. This paper reviews land use regulations in their institutional context and argues that conflicts in land use regulation are related to ideologies of land ownership and embedded in different planning doctrines. These hypotheses are investigated with special reference to Guangzhou, the capital of Guangdong Province in southern China. The evidence suggests that entangled land use regulations for “urban” and “rural” land have imposed serious constraints on urban growth, while the contradictions of different policies and regulations in the use of rural lands for urban construction have led to intensive and unhealthy competition among stakeholders. As a result, not only have the costs of land conversion from rural to urban uses increased, but the spatial development of Guangzhou has been distorted. The implications of these failures for future policy are discussed with emphasis on the reform of the land use regulation system.  相似文献   

3.
The increase of Earth's carrying capacity for human beings over the past few thousand years has been achieved by expansion of four main cultural complexes using relatively stable techniques to provide a narrow range of plant foods supplemented by a high proportion of animal protein. This process cannot continue much longer, reserves of arable land being inadequate even to replace durably land lost by erosion. Half the world's land is used for animal production. To assure future food and wood supplies, there should be changes in diet. Temperate countries should specialize In annual crops, and tropical ones in perennial crops and forestry.  相似文献   

4.
With land as Nigeria's most important asset, successive local and central governments have sought to control the acquisition of land so that it may be put to optimal use by the population of 70 million. The author looks into the theory of land acquisition and its history in Nigeria, with special reference to a number of irrigation projects. He examines in depth the actions and attitudes of the developers in several cases and notes a lack of consistency and consideration on their part. The author records the resulting opposition to any irrigation project due to the injustices such schemes have engendered in the past. He suggests a set of guidelines to bring an Improvement in relations between land-owners and the authorities, so that development projects are not held back and finally implemented in an atmosphere of hostility.  相似文献   

5.
Land administration systems, and particularly their core cadastral components, are an important infrastructure which facilitates the implementation of land use policies. While most land administration systems traditionally have a primary objective of supporting the operation of land markets, they are increasingly evolving into a broader land information infrastructure which supports economic development, environmental management and social stability in both developed and developing countries. While a great deal of attention is given to land use policies worldwide concerned with such areas as forest management, coastal zone management, environmental sustainability and managing the urban environment, less attention is given to the infrastructures which facilitate the implementation of the associated policies and programmes. Importantly, all these activities rely on some form of land administration infrastructure which permits the complex range of rights, restrictions and responsibilities in land to be identified, mapped and managed as a basis for policy formulation and implementation. As a result, there is an increasing interest in the concept of land administration infrastructures and their core cadastres, in the principles and policies concerned with establishing such infrastructures and in “best practices”. In addressing this need, this paper attempts to explain the evolving concept of land administration infrastructures, the concept of “best practice” and the concept of a land administration “tool box” of principles, policies, laws and technologies which are useful in reforming or re-engineering land administration systems in support of a broader land policy agenda.  相似文献   

6.
水资源约束下的黄淮海平原区土地利用结构优化   总被引:2,自引:0,他引:2  
[目的]黄淮海平原作为中国粮食的主产区,同时该区域水资源短缺问题日益加剧。如何在水资源可承载的条件下,保证粮食安全和经济发展,对黄淮海平原区土地利用结构的优化调整进行探索,具有重要意义。[方法]文章应用多元优化模型及遗传算法,在土地面积、宏观计划约束、粮食产量约束、市场约束等条件下,追求流域水资源平衡,同时保障粮食产量最大化,得到2020年黄淮海平原区土地利用结构优化方案,并通过土地转移矩阵,在2020年土地利用总体规划的约束下,依据2000~2010年土地利用变化路径,预测出2020年最大概率自然演化形成的土地利用结构。[结果]将最优方案与自然演化进行了土地利用结构、用水结构以及粮食产出3个方面对比,最优方案的粮食产量为8464.75万t,总耗水量减少18.56亿m~3,均优于自然演化结果,证明土地利用结构优化方案具有一定的有效性。[结论]黄淮海平原区土地利用结构优化的方向是在满足社会经济发展的情况下,尽量降低高耗水强度的建设用地面积占比,减少水资源匮乏流域的耕地面积,增加水资源较丰富流域的耕地面积,以保障粮食产量,充分利用未利用面积,增加林地、水域等生态用地的面积;优化后的土地利用结构,有效缓解了地下水水位下降的趋势。  相似文献   

7.
This review explores the role of land use and land use change as a determinant of the soil's ability to sequester and store carbon in the UK. Over 95 percent of the UK land carbon stock is located in soils which are subjected to a range of land uses and global changes. Land use change can result in rapid soil loss of carbon from peatlands, grasslands, plantation forest and native woodland. Soil carbon accumulates more slowly (decadal) but gains can be made when croplands are converted to grasslands, plantation forest or native woodland. The need for land for food production and renewable forms of energy could have considerable influence on UK soil carbon storage in the future. There is a need to recognise the risk of soil carbon losses occurring when land use change to increase carbon storage is offset by compensatory land use conversions elsewhere that result in net carbon release. The protection of peatland and other organic soil carbon stocks, and the management of cropland, grassland and forest soils to increase carbon sequestration, will be crucial to the maintenance of the UK carbon balance. It will be necessary to develop policy to balance trade-offs between soil carbon gains with other land use priorities. These include the sustainable production of food, bio-energy and fibre crops and livestock, water quality and hydrology, greenhouse gas emission control and waste management, all of which are underpinned by the soil.  相似文献   

8.
The main objective of the European Water Framework Directive (WFD) is the achievement of a good ecological and chemical status of the water environment (water bodies). This status corresponds to the limit value of Germany's Working Group of the Federal States on Water Problems Issues (LAWA) for water quality class II (3 mg/l total nitrogen). The rivers in the intensively cropped Upper Ems River basin (northwestern Germany) show total nitrogen concentrations in excess of 5–10 mg/l. Hence, the objective of our study was to find a land use and land management scenario that would reduce the total nitrogen concentration to meet the WFD requirements for good ecological and chemical status. We developed consecutive land use and management scenarios on the basis of policy instruments such as the support of agro-environmental measures by Common Agricultural Policy and regional landscape development programs. The model simulations were done by using the Soil and Water Assessment Tool (SWAT). Results of SWAT scenario calculations showed that drastic measures, which are unrealistic from a socio-economic point of view, would be needed to achieve the water quality target in the basin (reduction of arable land from 77.2% to 46% [13% organic farming], increase of pasture from 4% to 15%, afforestation from 10% to 21%, increase of protected wetlands from 0% to 9%, etc.). The example shows additionally that the achievement of the WFD targets is only possible with a consideration of regional landscape and land use distinctions. A related problem yet to be addressed is the general lack of measured water quality data with which to calibrate and validate water quality models such as SWAT. This adds considerable uncertainty to already complicated and uncertainty situations. Thus, improved strategies for water quality monitoring, and data accessibility must be established.  相似文献   

9.
基于土地利用变化的辉南县生态脆弱性时空变化分析   总被引:3,自引:0,他引:3  
山区平原过渡地带因其地质、地貌的特殊性而担负着自然地域界面的作用,并表现出更高的生态环境脆弱性,研究其脆弱性变化对山区平原生态安全预警非常重要。特别是从土地利用方式改变评价其生态脆弱性,对于土地利用方式调整和规划具有重要指导意义。本文以地处山区平原过渡区的辉南县为例,在分析其土地利用变化基础上,参照生态价值评估体系并结合周围生态环境敏感因子,建立生态脆弱性综合评价指标,对研究区1986年以来环境脆弱性的时空变化进行评价和分析。评价结果如下:(1)从不同用地类型看,生态综合指数大小顺序依次为林地、草地、水域、未利用地,其次是耕地和建设用地。(2)脆弱性时间变化特征:由于土地利用变化,特别是林地减少和耕地、建设用地增加,导致生态贡献指数、生态稳定性指数和生态综合指数显著下降,分别由1986年的2.999、3.324和6.322减小为2006年的2.828、3.032和5.861。(3)空间变化特征:全区范围内生态环境综合指数下降显著,表现为低值区域范围扩大,高值区域范围明显减小。高值区范围由1986年的33217.95ha缩小为2006年的1283.40ha,而低值区的范围则由1986年的86550.87ha扩大为2006年的98084.83 ha。(4)地区差异性:虽然三个生态指数在整体上呈现下降,但是不同子流域其变化表现出显著的差异性,总体上呈现东南山区减小,而西北平原区呈现不明显的增加特点。本文研究结果表明,导致研究区生态脆弱性的主要原因为林地减少和耕地增加。从保护生态环境角度,控制耕地增加和林地减少是有效防范措施。  相似文献   

10.
Land use,water management and future flood risk   总被引:1,自引:0,他引:1  
Human activities have profoundly changed the land on which we live. In particular, land use and land management change affect the hydrology that determines flood hazard, water resources (for human and environmental needs) and the transport and dilution of pollutants. It is increasingly recognised that the management of land and water are inextricably linked (e.g. Defra, 2004). “Historical context, state of the science and current management issues” section of this paper addresses the science underlying those linkages, for both rural and urban areas. In “Historical context, state of the science and current management issues” section we discuss future drivers for change and their management implications. Detailed analyses are available for flood risk, from the Foresight Future Flooding project (Evans et al., 2004a,b) and other recent studies, and so we use flooding as an exemplar, with a more limited treatment of water resource and water quality aspects. Finally in “Science needs and developments” section we discuss science needs and likely progress. This paper does not address the important topic of water demand except for some reference to the Environment Agency's Water Resources Strategy for England and Wales (Environment Agency, 2009).  相似文献   

11.
The concept of “inducing growth” is typically considered an adverse consequence of a project on the land use system. In certain instances, however, the desire to induce growth and foster land use change is a focus of land use policy. Such is the example of the Appalachian Highway Development System (AHDS) program initiated by the Appalachian Regional Commission (ARC) during the late 1960s. With the goal of providing highway infrastructure to improve assess to a geographically isolated and historically impoverished region, the ADHS has added nearly 3000 miles of highway to the Appalachian landscape. The degree to which highway investment has contributed to regional growth remains a controversial point and tractable methods to quickly assess landscape change given a project of this magnitude are elusive. In this paper a portion of the AHDS trending through southern Ohio is examined using data acquired from the Landsat series of satellites. Beginning with a pre-highway condition in 1976, a 26 year time horizon, concluding in 2002, was analyzed based on a post-classification change detection methodology. Results of this investigation revealed slight, yet significant, levels of urban expansion within a 10 km corridor along the path of AHDS Corridor D/State Route 32. Beyond this buffer zone the land use system evidenced more stability, suggesting that as distance increased from Corridor D/State Route 32, reduced accessibility also reduced the attractiveness of land for urban uses. Relating these results back to the infrastructure investment policies of the ARC demonstrates that growth did result from the construction of Corridor D and supports previous findings that land development based on highway construction is extremely time-sensitive.  相似文献   

12.
公众参与土地利用规划的探索--以浙江省嘉善县为例   总被引:1,自引:0,他引:1  
研究目的:探索公众如何参与土地利用规划的编制.研究方法:采用"头脑风暴法",以中加合作试点单位浙江省嘉善县为例,从城乡居民生活质量的改善作为规划的切入点,分7个步骤讨论公众参与土地利用规划的过程和方法.研究结果:公众采用"100美元"意向投资法,确定嘉善县的5项规划主题,即良好的区位条件、丰富的历史文化资源、水和空气受污染、建设用地利用效率低、农地保护政策缺乏弹性等,提出相应的行动计划.  相似文献   

13.
While addressing the issue of field encroachment and land use pattern changes in the desert margin regions, the paper proposes to develop a model which recognises land use pattern changes as event-driven. The picture that underpins development efforts and policy papers for environmental improvement in the Sudan–Sahel region often describes changes in agricultural landscape systems as a unidirectional expansion of fields onto marginal land in response to population pressure and resource degradation. It is proposed that models of land use pattern trajectories as well as of resilience of land use systems have to recognise a strong random element related to unforeseeable events.  相似文献   

14.
本文以大庆市为研究区,依据2001年和2009年的土地利用数据,从生态系统服务功能角度,运用Costanza的方法,结合谢高地修正的我国生态服务价值当量因子表,定量研究了土地利用变化引起的生态系统服务价值变化量。结果表明:2001~2009年间,研究区林地和城乡居民点及工矿用地面积增加,其余土地利用类型面积均有减少,其中林地的面积变化量最大。土地利用变化引起了研究区生态环境的变化,对生态系统服务价值也产生了一定的影响,大庆市9年间生态系统服务价值增加了41170.55万元,各单项服务功能价值中,其生态系统所提供的水源涵养、废物处理和食物生产等3项生态服务功能下降,其余6项生态系统服务功能均有不同程度的升高;从不同土地利用类型的生态服务功能看,湿地和水域的生态服务功能较强,只有林地的生态系统服务价值是增加的。  相似文献   

15.
[目的]为更加科学地分析区域土地利用驱动力机制、整体情况以及时空关系,支撑区域国土空间优化战略实施,文章立足于县域尺度,使用三峡库区1990年、2000年、2010年和2015年相关数据,构建土地利用变化驱动力评价指标体系。[方法]利用投影寻踪模型探寻库区土地利用变化驱动力的分异格局与驱动机制。[结果](1)土地利用驱动力呈现出空间地域的稳定性和时间序列的动态性,且驱动机制逐渐由"生计—经济"主导驱动型转变为"多元协同"驱动型;(2)库尾重庆主城区附近及库首宜昌市区周围土地利用驱动力较强,表现为城镇用地驱动型。位于渝东北和湖北巴东、秭归、兴山的土地利用驱动力较弱,体现为林草地和水体驱动型。而其他地区情况相对复杂,表现为多种类型驱动并存。[结论]在土地利用空间优化过程中,库区应结合不同区域土地利用驱动力的作用强度开展国土资源的空间重构与优化,对重庆主城区及宜昌市区附近区(县),应当考虑土地资源的综合利用,而广大库中地区则应在生态保护前提上寻求土地资源的增值效应。  相似文献   

16.
在水土流失严重、非农建设用地不断扩张以及可供开发利用的土地后备资源匮乏的大背景下,农业生产用地的有效使用成为当务之急。本文以复种指数、土地生产率、资金投入产出率和劳动力投入产出率等作为测度土地利用效率的指标,着重分析了土地细碎化和农户兼业等因素的影响。依据湖北省农村的随机抽样数据,实证分析得到的结论表明,土地细碎化对土地利用效率产生影响,在统计意义上不明显;农户兼业对复种指数的作用为正,对资金投入产出率的作用为负,对土地生产率和劳动力投入产出率的作用不显著;传统循环农业模式有利于提高土地利用效率。为此,本文提出必须毫不犹豫地坚持土地家庭承包经营方式不动摇;进一步加大"三农"投入力度;加快工业化和城镇化步伐,推动农村剩余劳动力尽快转移;大力扶持循环农业发展模式。  相似文献   

17.
Neoliberal land policies such as land administration seek to improve property rights and the efficiency of land markets to boost rural economic production. Quantitative studies of pre-existing land markets can help planners to tailor these policies to local conditions. In this article we examine an extra-legal land market currently being modernized by a World Bank-sponsored land administration effort. Specifically, we use a hedonic-type revealed preference model and household survey data to estimate the factors affecting extra-legal land prices along an agricultural frontier in Petén, Guatemala. Our model indicates that land value is significantly affected by land attributes including location, tenure status, presence of water, distance to roads, and distance to landowners’ homes, and that land prices in the northwestern Petén are estimated to have risen on average 26.5% per year between 1977 and 2000. We contend that this rate of increase provides a strong incentive for colonists to speculate in land rather than invest in state sanctioned property rights. We conclude that if frontier development programs, such as land administration, are to become attractive to settlers in Petén and elsewhere, they must compete favorably with economic incentives associated with land speculation, or alternatively, target landowners who are not interested in playing the land market.  相似文献   

18.
The author notes the failures of post-war development of the inner cities in the UK and the serious social consequences these have had on the quality of life. A previous study on housing design in New York is outlined and the author explains the findings of very recent work by the Land Use Research Unit at King's College, London. This study was based in Oxford and London and took six types of social malaise (all related to the activities of children) as test measures for analysing the effects of 18 design variables. The findings for the blocks of flats were compared with a sample of 350 houses. A list of recommendations is given and the author finally calls for independent research in this field and a new approach to the subject of land use.  相似文献   

19.
Possessing ecological service functions, as well as social and economic values, urban lakes are an important part of urban open spaces. The improvement in the openness of urban lakes is crucial to enhancing the efficiency and fairness of urban land use. Accompanied by China's rapid urbanization, China's urban land prices continue to rise and the government relies on land finance. Meanwhile, the number of urban lakes is decreasing, the lake water surface area is shrinking, and water pollution is becoming more serious. By using exploratory indicators, this study quantifies the degree of openness of urban lakes, and focuses on the relationship between lake spatial openness and neighboring land prices. Taking Wuhan (China) as a study case, we proposed a conceptual framework to guide the analysis within the context of land use policy. Then, we created exploratory indicators to quantify the spatial openness of urban lakes and mapped the results. Afterward, we conducted an exploratory geovisual analytics of urban land prices and lake spatial openness. Finally, we used a regression model to examine the relationship between prices and openness. Our results show that our new indicators were able to reflect the openness of the lakes in the central urban area of Wuhan simply and effectively. The overall spatial openness is relatively high, the mean values of two main indicators reflecting the openness percentage of the lakes are 69.91 % and 67.57 % respectively. However, there are still obvious regional differences between the openness indicators. The relationship between openness and neighboring land prices is spatially heterogeneous. Based on our analysis, we finally propose policy suggestions for protecting urban lakes and rational land use in the rapid urban expansion occurring in developing countries.  相似文献   

20.
论土地规划的环境影响评价   总被引:38,自引:4,他引:38  
研究目的:<中华人民共和国环境影响评价法>确立了中国的环境影响评价制度,作者为开展土地利用规划的环境影响评价提供参考.研究方法:文献资料综合分析法、借鉴已经开展的有关工作的经验与相关领域的研究成果的方法.研究结论:将LUPEIA分为LUOPEIA、LUSPEIA、LUPPEIA三个层次,初步构建了中国LUPEIA体系;提出了基于PSR框架、FAO相关文件及项目EIA的LUPEIA方法论,建立了基于PSR框架的地市级土地利用规划环境评价指标体系,讨论了FAO相关文件在LUPEIA的作用,将土地利用持续性评价归结为LUPEIA的主要内容,土地利用结构的调整与空间布局对环境的影响是LUPEIA的特色,美国国家环保局的BASINS工具对土地利用造成的流域水环境质量影响评价是值得借鉴的方法.  相似文献   

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