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1.
大庆市土地利用/土地覆盖景观格局研究   总被引:3,自引:0,他引:3  
利用遥感影像处理系统,对大庆市1978~2001年5个时段的TM影像进行处理,得到大庆市土地利用图;据图进行土地利用/土地覆盖景观格局分析,利用GIS软件计算出大庆市区土地利用/土地覆盖的破碎化、斑块形状、分离度、优势度、均匀性及多样性等景观指数,并对大庆市区土地利用/土地覆盖进行自相关分析;结果表明,作为一个典型的石油型城市,大庆市景观格局有其独特之处。  相似文献   

2.
土地利用/覆被变化(LUCC)是人类活动对自然环境施加影响的显著表现形式。本文以案例的形式,运用LUCC度量模型和LUCC转移矩阵分析研究区清新县2001-2007年的LUCC空间格局变化,并对全县土地利用/覆被进行了分区。研究结果表明,清新县2001-2007年面积增加最多的为林地,而减小最多的为耕地,期间全县综合土地利用/覆被动态度为2.77%、土地利用/覆被强度从2.163增至2.172;同时,清新县土地利用/覆被存在着较为明显的空间差异,全县土地利用/覆被区划可分为南部综合服务中心区、中部产业转移区和北部生态脆弱区三个功能区。  相似文献   

3.
Extreme farmland ownership fragmentation is becoming a limiting factor for sustainable land management in some countries. Scattered, excessively small parcels cease to be viable for individual farming, and owners feel forced to rent these parcels to larger enterprises farming on adjacent land. Our study demonstrates a phenomenon that we call the Farmland Rental Paradox, where very small parcels tend to create large production blocks by being rented to larger farmers, and therefore to significantly homogenize the land-use pattern. The parcel size established as the threshold for this phenomenon is 1.07 ha. Below this threshold, the smaller the parcels were, the larger the blocks that they tended to create.Using the example of the Czech Republic, a state with extremely high farmland ownership fragmentation, it is demonstrated that this phenomenon can currently determine the land use of up to 40% of the country's farmland. Our study also points to other countries where this phenomenon may apply, especially the transitional countries of Central and Eastern Europe.The study discusses the tempo of the fragmentation process, which accelerates exponentially in countries with the equal inheritance system. It goes on to discuss defragmentation, social impacts of the dominance of the land rental market, and environmental impacts of significant homogenization of the land-use pattern. The serious negative impacts of extreme land-ownership fragmentation show that this phenomenon can be considered as a significant form of land degradation.  相似文献   

4.
In the complex agro-ecological conditions of Vietnam's northern borderlands, attempts by ethnic minority farmers to create sustainable livelihoods, along with the impacts of state development policies, have direct consequences for land use and land cover (LULC) change. In this paper we analyse the degree to which LULC has changed and diversified from 1999 to 2009 in Lào Cai Province and the underlying relationships with ethnic minority livelihood diversification strategies. We examine the correlation between LULC diversity and various socioeconomic and biophysical proxies using a spatial autoregressive model. Our findings indicate two major changes in LULC: an increase in closed canopy forest and substantial urban growth. LULC diversity increased between 1999 and 2009, suggesting a transition between land uses and/or a diversification of livelihood strategies. Socioeconomic proxies are significant predictors of LULC diversity in both years, while biophysical proxies are only effective predictors in 2009. In-depth interviews regarding state-led policies and ethnic minority livelihoods reveal some of the underlying mechanisms of such LULC transitions and associations.  相似文献   

5.
浅析现行土地利用/覆盖变化描述方法   总被引:2,自引:0,他引:2  
土地利用/覆盖变化是当前全球变化研究的热点问题之一;将土地利用/覆盖变化的描述方法分为土地利用时空变化和景观格局两个方面,分别从土地利用程度、动态变化速度、位置迁移和转换方向及来源方向等角度分析,对土地利用变化过程中的景观格局指数的变化规律总结归纳,并对指数的适宜性作以分析。  相似文献   

6.
The Central American Dry Corridor (CADC) is a trans-border region characterized by climatic and ecological continuities. It is expected to experience rising aridity and severe hydro-climatic events due to climate change. Subsistence agriculture and other rural livelihoods to which land cover is central are widely practiced in this impoverished territory of approximately eleven million people.The CADC’s land cover was profiled to determine: a) how it differs from Non-CADC areas, and b) the role of land use in shaping these differences. Spatial autocorrelation analysis using satellite data showed that forest cover is a third less prevalent in the CADC than in the Non-CADC while the share of mosaic vegetation and mosaic cropland is nearly double. A naturally prevalent cover type in the CADC, tropical dry forest (TDF), has been largely eliminated.The significantly lesser proportion of forest and greater percentage of coverage consistent with agriculture and ranching implicate land use conversion, specifically deforestation for agricultural expansion and cattle ranching, in shaping CADC land coverage. The process began in the mid-1800s when small-scale agriculturalists migrated to the region followed by large-scale export crop and beef production, primarily for international markets. Deforestation peaked after WWII, concluding by the 1990s with the conversion of most woodlands. Similar patterns now threaten forests along the Caribbean coast.Traditional land use practices cannot sustain local communities or preserve the resource base, thereby contributing to rural outmigration. Adopting sustainable practices and promoting livelihoods strategies leading to forest regeneration will be fundamental for CC adaptation in the CADC.  相似文献   

7.
甘肃省酒泉市近年来经济发展迅速,但生态环境也遭到一定程度的破坏;拟通过对其土地利用和覆盖变化的研究,为环境保护与经济协调发展提供决策支持;依据肃州区1988~2000年土地利用变更调查数据,对该区域LUCC进行分析,确定了土地利用类型的转移概率矩阵,并用马尔柯夫链模型预测了该区LUCC趋势。结果表明,肃州区土地利用将呈现耕地、水域和建设用地增加,林地、草地和未利用土地减少的发展趋势。  相似文献   

8.
The protection of agricultural land and forests is a relatively new concept in Poland, and it began with forest protection in the 1920s. The first regulations on the protection of agricultural land were introduced only in the 1960s. Agricultural land and forests received comprehensive protection pursuant to the provisions of the Act of 26 October 1977 on the protection of agricultural land, forests and land recultivation. This legal act set the foundations for the protection of farmland and forests in successive decades.The aim of this study was to determine the influence of farmland and forest protection on spatial planning and to highlight the loss of agricultural and forest land resulting from conversion to other purposes. Legal regulations pertaining to spatial planning and the protection of agricultural and land forests were analysed. The scale of the problem was identified, and future land-use types were forecast based on the data developed by Statistics Poland (GUS). The existing spatial plans (municipal master plan - MMP) were analysed to determine the conversion loss index (CLI) associated with the conversion of agricultural land and forests to other uses. Legal regulations pertaining to the protection of agricultural land and forests were also analysed, and the extent of the relevant conversion measures was determined. The study demonstrated that urban development and the inevitable urbanization of rural areas contribute to the loss of agricultural and forest land that are converted to other uses.  相似文献   

9.
Changes in land use and land tenure can influence both physical fragmentation and ownership fragmentation of landscapes, with implications for biodiversity. In this study, we evaluated changes in land use and land tenure in the Tijuana River Watershed, a region of high biodiversity and endemism, following the implementation of a new Agrarian Law which allowed for privatization and sales of communal land (ejidos) beginning in 1992. In order to understand changes in land use and cover, we constructed maps from aerial photographs and Aster images and measured changes between 1994 and 2005. In order to understand changes in land tenure, we collected data from Mexican government sources on ejido land size, ownership, and sales, and we conducted 55 structured interviews with ejidatarios in the watershed. Our results demonstrate that land-use/cover change between 1994 and 2005 was dominated by an increase in urban area and grasslands, and a decrease in coastal sage scrub, chaparral, and, to a lesser degree, agriculture. In particular, the conversion of coastal sage scrub has left a far more fragmented landscape than existed in 1994. In addition, most of the ejidos in the watershed, as well as individuals interviewed, had participated in some stage of the land certification and titling process allowed by the new Agrarian Law, resulting in substantial changes in land tenure. However, land tenure security appeared to play a larger role than a desire to sell land and, contrary to studies from other regions, full title to the land was obtained in a range of urban and rural settings, rather than primarily on land closest to urban zones. Our results suggest that past predictions regarding future urban growth and fragmentation of native vegetation in the region have proven accurate and highlights regions of change that merit further study.  相似文献   

10.
Historically the land development process has lacked a decision support structure for evaluating undeveloped parcels of land for compatibility with land use policy and engineering constraints. This paper demonstrates an applied multi-criteria decision support structure for characterizing the spatial distribution and classification of a parcel’s potential to support residential lot construction. This support structure is based on parcel attributes quantified in a typical site feasibility report, to include: potential house yield, wetlands area, soil types, streams (surface drains), and steep slope areas. The analytical capabilities of geographic information system (GIS) are employed in the decision support structure named the constructability assessment method (CAM). CAM integrates a dynamic multi-criteria attribute assessment method, based on the Analytical Hierarchy Process (AHP), for a given set of administrative requirements, and engineering constraints and judgment.The results of a case study using CAM characterized the approximate location of ideal lots for homes construction in an R-1 zoning district located on a 1290 acre land parcel in Loudoun County, VA, while avoiding existing hydric soils, floodplains, steep slopes, and forested areas. The number of ideal lots for a given set of engineering and administrative constraints represented a 65% reduction from the maximum lots permitted by regulatory constraints alone. The methodology used in this case study provides a consistent and repeatable land parcel analysis technique for undeveloped land parcels, and can be adapted and/or extended to a number of similar publicly available geographic datasets and constraint. In estimating optimal development density, CAM meets the needs of zoning administrators as well as the developers, thus offering a demand-driven market-based solution for sustainable land development.  相似文献   

11.
We solve Faustmann's problem when the land manager plans to switch from the current tree species to some alternative species or land use. Such situations occur when the value of the alternative increases relative to the value of the species currently in place. The paper characterizes the land value function and the optimum rotations, highlighting the differences between this non-autonomous problem and the traditional Faustmann problem. We show that, from one harvest to the next until the switch, rotations can be constant and equal to the Faustmann rotation, or increasingly higher than the Faustmann rotation, or decreasingly lower. In the last two situations, the higher the number of previous harvests of the currently planted species before the switch to the alternative use, the closer the last rotation is to the Faustmann rotation.  相似文献   

12.
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   

13.
通过GIS空间分析功能,选取常德市的四个县市:桃源县、汉寿县、临澧县、津市市,从土地利用现状、土地利用时空变化、土地利用类型动态度、土地利用程度变化以及土地利用变化区域差异等五个方面对常德市2009年和2012年土地利用、覆被变化进行定量、定性分析比较。研究结果表明:12009-2012年期间,四个县市的城镇、交通水利等建设用地需求持续增加;2 2009-2012年期间,土地利用程度综合指数呈增长的趋势;3常德市2009-2012年间土地利用程度变化不大,并且区域不平衡;4 2009-2012年期间,四个县市中相对变化最大的为临澧县城镇建设用地。  相似文献   

14.
China has implemented land use master plans to strictly control built-up land usage. The effective evaluation of land use master plan on controlling construction land is the premise of monitoring and early warning of planning implementation. It is also the basis for planning revision and further implementation of territorial spatial planning. In this study, we established a comprehensive index system based on three aspects: scale management, annual growth rhythm control, and spatial layout. We then analyzed the consistency between the actual situation for built-up land and the previous land use master plan of the Jinan Municipality in the Shandong Province of eastern China. The results showed that the master plan effectively controlled the scale of built-up land sprawl, such that the annual growth rhythm control level periodically increased over time. They also indicated the low efficiency of the built-up land spatial layout control. Overall, the previous land use master plan in Jinan had notable impacts. We recommend that land policy makers should adjust control standards and implementation intensity for spatial planning in the future to achieve scientific and effective planning for the management of construction land.  相似文献   

15.
Land use policy is administered at the local level in the U.S. However, many of the benefits and costs have broader spatial impacts. Thus, a lack of coordination across local jurisdictions may lead to unintended spillovers. Using historical data from the Baltimore, Maryland metro, we examine the impact that an extensive zoning policy change in Baltimore County had on new housing supply in surrounding counties. Defining treatment and control locations in surrounding counties based on their adjacency to Baltimore County, we find that the change in zoning policy led to an increase in housing supply of 42%–97% in adjacent counties. In both spatial and temporal falsification tests, we fail to find evidence of a spillover effect suggesting that the increased development was likely the result of spillovers from uncoordinated policy.  相似文献   

16.
G.W. Page  R.S. Berger   《Land use policy》2006,23(4):551-559
This paper reports exploratory empirical research on the property characteristics and land use of contaminated brownfield properties. This research investigated 1415 contaminated brownfield properties in environmental cleanup programs in the states of New York and Texas in the US. This research attempts to clarify some confusion about contaminated brownfield sites, provide detailed information on the diverse land uses that caused the contamination on these properties, and to provide a better base of knowledge about brownfield sites that may be used in developing and implementing policy to remediate and redevelop contaminated brownfields properties in both older industrial regions and in more recently industrialized regions. This research analyzed land use data for these properties at the time they became contaminated and at the time they entered the environmental cleanup program. It also attempts to identify similarities and differences in the characteristics of the properties in these two states with strikingly different histories of industrialization. Several common assumptions about brownfield properties are extracted from the literature review and tested using the data. Some of our results are surprising, including the variety of past land uses of these contaminated brownfield properties and the differences in the history of land use and the characteristics of the properties in the older versus newer industrial region.  相似文献   

17.
18.
Land use and land cover changes play an important role in the occurrence of vector-borne diseases. It is highly essential to identify the prominent changes responsible for its occurrence so that suitable measures can be adopted. An attempt was made to identify the prominent land use and land cover changes responsible for the spread of chikungunya, malaria, and dengue fever in the State of Kerala, India, using hierarchical cluster analysis and multiple regression analysis. Large extent of water bodies, low land and agricultural land played a significant role on the incidence of chikungunya and malaria. High population density, built-up area and agricultural area favoured dengue fever. Vector-borne diseases were found to be the lowest in places where there is no low land and with higher forest area. Inappropriate disposal of wastes generated in the built-up area might be the reason for the spread of dengue fever. Freshwater in drains of these areas is polluted and form breeding grounds for mosquitoes. Hence much attention is to be paid to provide appropriate treatment and disposal of wastes generated in the built-up area of the State In an evolving urban policy, priority is to be given to the installation of safe treatment and disposal facility of wastes especially, sewage, sullage, and solid waste. The protection of forest land also plays an important role. Economic policy instruments such as Payment for Environment Services (PES) schemes, may constitute a useful tool to encourage an improved land use management through appropriate price signals, such as, for instance, for the preservation of forested areas especially in proximity of highly populated urban environments.  相似文献   

19.
Tea expansion, a typical process of regional land use and cover change (LUCC), has raised great concerns on regional sustainability. In this regard, exploring the determinants of tea expansion should provide critical implications for land use policy. It has been widely recognized that LUCC interacts nonlinearly with a set of determinants and their feedbacks should be rather complex. Policy makers are now facing the challenge to identify, apportion, and compare the determinants of regional tea expansion for designing more targeted political intervenes. Our paper utilizes a robust tool, the random forest (RF) regression in particular, to explore the determinants of tea expansion across two periods (1985–2007 and 2007–2016) in Anji County, a typical region of tea production in subtropical China. More specifically, tea is extracted from Landsat imageries and total tea cultivated area acts as the dependent variable. Exploratory variables include 38 potential determinants and these determinants are divided into two categories (biophysical and socioeconomic) at two levels (pixel and village). We obtain some similar findings, though the relative importance of determinants varies with the two periods. In general, biophysical determinants (e.g., topography, soil type, land use in the neighborhood) present greater relative importance than the socioeconomic determinants in both periods. In period 1985–2007, biophysical determinants at pixel level are more essential in governing tea expansion. In period 2007–2016, the relative importance of pixel level biophysical determinants is comparable with that of the village level determinants. Comparisons of the two periods indicate that relative importance of soil type and socioeconomic proximity becomes greater in period 2007–2016, while that of the total employees and non-agricultural population proportion becomes lower. Partial dependency plots are further drawn to visualize the marginal effect of each determinant. We finally propose three options for land use policy towards sustainability. Our study demonstrates that the RF regression is efficient for policy makers to understand the determinants of tea expansion with a nonlinear and complex nature.  相似文献   

20.
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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