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1.
Land use/cover change is an important theme on the impacts of human activities on the earth systems and global environmental change. National land-use changes of China during 2010–2015 were acquired by the digital interpretation method using the high-resolution remotely sensed images, e.g. the Landsat 8 OLI, GF-2 remote sensing images. The spatiotemporal characteristics of land-use changes across China during 2010–2015 were revealed by the indexes of dynamic degree model, annual land-use changes ratio etc. The results indicated that the built-up land increased by 24.6×103 km2 while the cropland decreased by 4.9×103 km2, and the total area of woodland and grassland decreased by 16.4×103 km2. The spatial pattern of land-use changes in China during 2010–2015 was concordant with that of the period 2000–2010. Specially, new characteristics of land-use changes emerged in different regions of China in 2010–2015. The built-up land in eastern China expanded continually, and the total area of cropland decreased, both at decreasing rates. The rates of built-up land expansion and cropland shrinkage were accelerated in central China. The rates of built-up land expansion and cropland growth increased in western China, while the decreasing rate of woodland and grassland accelerated. In northeastern China, built-up land expansion slowed continually, and cropland area increased slightly accompanied by the conversions between paddy land and dry land. Besides, woodland and grassland area decreased in northeastern China. The characteristics of land-use changes in eastern China were essentially consistent with the spatial govern and control requirements of the optimal development zones and key development zones according to the Major Function-oriented Zones Planning implemented during the 12th Five-Year Plan (2011–2015). It was a serious challenge for the central government of China to effectively protect the reasonable layout of land use types dominated with the key ecological function zones and agricultural production zones in central and western China. Furthermore, the local governments should take effective measures to strengthen the management of territorial development in future.  相似文献   

2.
Resettlement of people displaced by dam projects is an important development issue. Land lost due to the Three Gorges reservoir inundation and the adjustment of land-use policy in China resulted in land-use changes, and impacted on the human carrying capacity of the land and the land availability for resettlement. The Chinese government has implemented a ‘development-oriented resettlement’ policy and a ‘near resettlement’ approach to relocating rural dwellers affected by the Three Gorges Project (TGP). Based on recent land-use survey and population data of the case study area and using GIS-based multi-criteria analysis in land-use planning, this study analyses the characteristics and changes of land use in both the inundation and resettlement areas. Undeveloped land is scarce in both areas. The non-flooded cultivated land is distributed mainly on steep slopes (over 25 degrees). There is a discrepancy between the amount of land required by those being resettled and what is available in the designated resettlement communities. This study suggests that resettlement should consider the human carrying capacity of the land and, from a community standpoint, sheds light on the interplay between land-use planning and resettlement, and provides constructive suggestions for TGP resettlement strategies.  相似文献   

3.
Land-use/land-cover changes (LUCCs) have links to both human and nature inter- actions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year inter- vals from the late 1980s to 2010, with standard procedures based on Landsat TM/ETM+ im- ages. A land-use dynamic regionalization method was proposed to analyze major land-use conversions. The spatiotemporal characteristics, differences, and causes of land-use changes at a national scale were then examined. The main findings are summarized as fol- lows. Land-use changes (LUCs) across China indicated a significant variation in spatial and temporal characteristics in the last 20 years (1990-2010). The area of cropland change de- creased in the south and increased in the north, but the total area remained almost un- changed. The reclaimed cropland was shifted from the northeast to the northwest. The built-up lands expanded rapidly, were mainly distributed in the east, and gradually spread out to central and western China. Woodland decreased first, and then increased, but desert area was the opposite. Grassland continued decreasing. Different spatial patterns of LUC in China were found between the late 20th century and the early 21st century. The original 13 LUC zones were replaced by 15 units with changes of boundaries in some zones. The main spatial characteristics of these changes included (1) an accelerated expansion of built-up land in the Huang-Huai-Hai region, the southeastern coastal areas, the midstream area of the Yangtze River, and the Sichuan Basin; (2) shifted land reclamation in the north from northeast China and eastern Inner Mongolia to the oasis agricultural areas in northwest China; (3) continuous transformation from rain-fed farmlands in northeast China to paddy fields; and (4) effective- ness of the "Grain for Green" project in the southern agricultural-pastoral ecotones of Inner Mongolia, the Loess Plateau, and southwestern mountainous areas. In the last two decades, although climate change in the north affected the change in cropland, policy regulation and economic driving forces were still the primary causes of LUC across China. During the first decade of the 21st century, the anthropogenic factors that drove variations in land-use pat- terns have shifted the emphasis from one-way land development to both development and conservation. The "dynamic regionalization method" was used to analyze changes in the spatial patterns of zoning boundaries, the internal characteristics of zones, and the growth and decrease of units. The results revealed "the pattern of the change process," namely the process of LUC and regional differences in characteristics at different stages. The growth and decrease of zones during this dynamic LUC zoning, variations in unit boundaries, and the characteristics of change intensities between the former and latter decades were examined. The patterns of alternative transformation between the "pattern" and "process" of land use and the causes for changes in different types and different regions of land use were explored.  相似文献   

4.
基于遥感影像数据的汉川市土地利用动态变化探讨   总被引:1,自引:0,他引:1  
以1991~2002年汉川市土地利用遥感数据为基础,选取土地利用变化幅度、动态度、土地利用程度指数及景观生态学指标中的多样性、均衡度和优势度指数,对研究区的土地利用变化状况和驱动力因素进行分析。结果表明:1991年以来,汉川市土地利用结构中,水域、未利用地有所减少,建设用地增加,林地、耕地变化幅度和动态度最大;12年来汉川市土地利用处于调整和发展期,生态景观和均质程度在上升。综合分析表明,人口、经济、政策在土地利用变化中起着主导作用。  相似文献   

5.
贵州猫跳河流域土地利用变化和土壤侵蚀(英文)   总被引:4,自引:2,他引:2  
Due to the extremely poor soil cover, a low soil-forming rate, and inappropriate intensive land use, soil erosion is a serious problem in Guizhou Province, which is located in the centre of the karst areas of Southwest China. In order to bring soil erosion under control and restore environment, the Chinese Government has initiated a serious of ecological rehabilitation projects such as the Grain-for-Green Programme and Natural Forest Protection Program and brought about tremendous influences on land-use change and soil erosion in Guizhou Province. This paper explored the relationship between land use and soil erosion in the Maotiao River watershed, a typical agricultural area with severe soil erosion in central Guizhou Province. In this study, we analyzed the spatio-temporal dynamic change of land-use type in Maotiao River watershed from 1973 to 2007 using Landsat MSS image in 1973, Landsat TM data in 1990 and 2007. Soil erosion change characteristics from 1973 to 2007, and soil loss among different land-use types were examined by integrating the Revised Universal Soil Loss Equation (RUSLE) with a GIS environment. The results indicate that changes in land use within the watershed have significantly affected soil erosion. From 1973 to 1990, dry farmland and rocky desertified land significantly increased. In contrast, shrubby land, other forestland and grassland significantly decreased, which caused accelerated soil erosion in the study area. This trend was reversed from 1990 to 2007 with an increased area of land-use types for ecological use owing to the implementation of environmental protection programs. Soil erosion also significantly varied among land-use types. Erosion was most serious in dry farmland and the lightest in paddy field. Dry farmland with a gradient of 6°-25° was the major contributor to soil erosion, and conservation practices should be taken in these areas. The results of this study provide useful information for decision makers and planners to take sustainable land use management and soil conservation measures in the area.  相似文献   

6.
Climate change adaptation (CCA) ‘barriers’ are frequently seen as responses to biophysical climate impacts, and thus defined as ‘obstacles’ to be ‘overcome’, rendered into categories of the techno-managerial. However, barriers are often undertheorized and are blind to explanations of their origins or the causal mechanisms by which they operate. This is especially complex for barrier critiques in the Global South in particular. Using a ‘hybrid’ assemblage and postcolonial approach, this paper disentangles existing barrier critiques in Thailand to lay bare underlying power imbalances and tensions. It finds that ‘simplistic’ vulnerability framings have deep roots in postcolonial histories; ‘complacent’ mainstreaming/budgeting trajectories have been nurtured by various IOs, and not necessarily much-maligned Thai bureaucrats; and limited technical expertise/willingness to engage are not so illogical, but rather results of diverse external forces. Given this, this paper urges institutional actors and researchers to reflect on epistemology, ontology, and their own positionality when assessing barriers in future.  相似文献   

7.
基于PSR模型的农区土地利用冲突强度的诊断   总被引:6,自引:0,他引:6  
杨永芳  安乾  朱连奇 《地理科学进展》2012,31(11):1552-1560
随着工业化、城镇化进程的加快,农村土地利用冲突越来越多,分析不同农区土地利用冲突的形式,评估土地利用冲突的强度,对农村发展具有重要意义.本文采用相关分析、主成分分析的方法,从引起鄢陵县耕地利用变化的32 个因子中,提取了6 个主要压力因子,根据鄢陵土地利用结构变化情况和区域政策、制度及其社会响应状况,建立特色农区土地利用冲突强度的评价指标体系,用加权函数法进行冲突强度的评价.研究表明,土地利用冲突强度呈波动增加趋势;土地利用冲突的原因主要是:①经济发展及经济结构调整因素;②农业种植结构的调整;③科技进步以及政策等因素的影响.因此,政府可通过市场手段、规划制度等进行调控,提高区域土地资源的配置效率,引导土地利用方式的规范转化,以减缓或化解土地利用冲突.  相似文献   

8.
Land-use/land-cover changes (LUCCs) have links to both human and nature interactions. China's Land-Use/cover Datasets (CLUDs) were updated regularly at 5-year intervals from the late 1980s to 2010,with standard procedures based on Landsat TM\ETM+ images. A land-use dynamic regionalization method was proposed to analyze major land-use conversions. The spatiotemporal characteristics,differences,and causes of land-use changes at a national scale were then examined. The main findings are summarized as follows. Land-use changes (LUCs) across China indicated a significant variation in spatial and temporal characteristics in the last 20 years (1990-2010). The area of cropland change decreased in the south and increased in the north,but the total area remained almost unchanged. The reclaimed cropland was shifted from the northeast to the northwest. The built-up lands expanded rapidly,were mainly distributed in the east,and gradually spread out to central and western China. Woodland decreased first,and then increased,but desert area was the opposite. Grassland continued decreasing. Different spatial patterns of LUC in China were found between the late 20th century and the early 21st century. The original 13 LUC zones were replaced by 15 units with changes of boundaries in some zones. The main spatial characteristics of these changes included (1) an accelerated expansion of built-up land in the Huang-Huai-Hai region,the southeastern coastal areas,the midstream area of the Yangtze River,and the Sichuan Basin;(2) shifted land reclamation in the north from northeast China and eastern Inner Mongolia to the oasis agricultural areas in northwest China;(3) continuous transformation from rain-fed farmlands in northeast China to paddy fields;and (4) effectiveness of the "Grain for Green" project in the southern agricultural-pastoral ecotones of Inner Mongolia,the Loess Plateau,and southwestern mountainous areas. In the last two decades,although climate change in the north affected the change in cropland,policy regulation and economic driving forces were still the primary causes of LUC across China. During the first decade of the 21st century,the anthropogenic factors that drove variations in land-use patterns have shifted the emphasis from one-way land development to both development and conservation.The "dynamic regionalization method" was used to analyze changes in the spatial patterns of zoning boundaries,the internal characteristics of zones,and the growth and decrease of units. The results revealed "the pattern of the change process," namely the process of LUC and regional differences in characteristics at different stages. The growth and decrease of zones during this dynamic LUC zoning,variations in unit boundaries,and the characteristics of change intensities between the former and latter decades were examined. The patterns of alternative transformation between the "pattern" and "process" of land use and the causes for changes in different types and different regions of land use were explored.  相似文献   

9.
20世纪90年代新疆草地资源的空间格局演变   总被引:18,自引:0,他引:18  
以Landsat TM遥感影像解译出的新疆1990年和2000年1:10万土地利用数据为基础,探讨了近10年来草地资源的动态变化及其空间格局特征。两期矢量数据叠加,得到耕地、林地、草地、水域、建设用地和未利用土地的面积变化数据、土地利用类型动态度和土地利用变化转移概率矩阵,从而系统地分析了草地与其他土地利用类型之间以及高、中、低不同覆盖度草地亚类之间的动态变化。在归纳草地资源各种变化情况的基础上,构建无任何分类面积信息损失的ARC/INFO-Grid格网化数据集,从而讨论了草地资源动态变化的空间格局特征。研究表明,近10年来草地与未利用土地之间为近似等量交换,与其他土地利用类型之间的转换则是显著的入不敷出,因此草地大量减少,但是草地总体质量的提高在很大程度上弥补了其总量减少的不利影响。草地数量的转入与转出及质量的提高与恶化在时间上同步发生,在空间上则交错进行并形成复杂的空间格局。草地资源的动态变化总体上具有比较突出的区域差异性,可以划分出5个基本动态变化分区。  相似文献   

10.
Cellular automata (CA) have been widely used to simulate complex urban development processes. Previous studies indicated that vector-based cellular automata (VCA) could be applied to simulate urban land-use changes at a realistic land parcel level. Because of the complexity of VCA, these studies were conducted at small scales or did not adequately consider the highly fragmented processes of urban development. This study aims to build an effective framework called dynamic land parcel subdivision (DLPS)-VCA to accurately simulate urban land-use change processes at the land parcel level. We introduce this model in urban land-use change simulations to reasonably divide land parcels and introduce a random forest algorithm (RFA) model to explore the transition rules of urban land-use changes. Finally, we simulate the land-use changes in Shenzhen between 2009 and 2014 via the proposed DLPS-VCA model. Compared to the advanced Patch-CA and RFA-VCA models, the DLPS-VCA model achieves the highest simulation accuracy (Figure-of-Merit = 0.232), which is 32.57% and 18.97% higher respectively, and is most similar to the actual land-use scenario (similarity = 94.73%) at the pattern level. These results indicate that the DLPS-VCA model can both accurately split the land during urban land-use changes and significantly simulate urban expansion and urban land-use changes at a fine scale. Furthermore, the land-use change rules that are based on DPLS-VCA mining and the simulation results of several future urban development scenarios can act as guides for future urban planning policy formulation.  相似文献   

11.
谢花林  李波 《地理研究》2008,27(2):294-304
本文以农牧交错带的典型区域——内蒙古翁牛特旗为例,考虑土地利用变化过程的空间变量,建立了不同土地利用变化过程的logistic回归模型。结果表明:模型中转为耕地的主要解释变量是到农村居民点的距离和农业气候区;转为草地的主要解释变量是到农村居民点的距离、土壤表层有机质含量和到乡镇中心的距离;转为林地的主要解释变量是到农村居民点的距离和海拔;空间异质性和土地利用变化过程的时间变量共同影响着使用logistic回归模型来解释土地利用变化驱动力的能力;通过对草地logistic回归模型的检验,得出空间统计模型能较好地揭示不同土地利用变化过程的主要驱动力及其作用机理。  相似文献   

12.
CLUE-S模型是一个基于经验统计原理的模拟多土地利用类型空间变化的动态模拟模型,它在世界多个国家和地区的区域尺度农业、森林为主的土地利用变化模拟中得到应用。作者对CLUE-S模型进行了改进,改进后的模型 (CLUE-SII) 引入了动态计算的邻域分析因子,可以对土地利用变化中的自发过程、自组织过程和土地利用类型间的竞争进行模拟,还可以根据研究区域特点构建不同的模拟方案,在这些模拟方案中,局地因子和邻域因子在土地利用变化中的作用方式不同。应用CLUE-SII对北京市海淀区1991~2001年土地利用变化进行了多方案模拟,结果表明邻域因子对城镇用地变化具有重要作用,其中将邻域因子看作自发过程放大因子的模拟方案获得了较好的模拟结果,整图符合比达到77%,其中城镇用地符合比达到82%,Kappa值达到0.754。CLUE-SII在北京市海淀区的应用实例表明,该模型可以对高分辨率和多土地利用类型下的城市扩展进行有效模拟,扩展了CLUE-S的应用领域;通过构建多模拟方案,不但可以探索最佳的模拟结果,还可以研究和分析不同土地利用驱动因子在土地利用变化中的作用模式。  相似文献   

13.
In the mid-1990s, we established the national operative dynamic information serving systems on natural resources and environment. During building the land-use/land-cover change (LUCC) database for the mid-1990s, 520 scenes of remotely sensed images of Landsat Thematic Mapper (TM) were interpreted into land-use/land-cover categories at scale of 1:100,000 under overall digital software environment after being geo-referenced and ortho-rectified. The vector map of land-use/land-cover in China at the scale of 1:100,000 was recently converted into a 1-km raster database that captures all of the high-resolution land-use information by calculating area percentage for each kind of land use category within every cell. Being designed as an operative dynamic information serving system, monitoring the change in land-use/land-cover at national level was executed. We have completed the updating of LUCC database by comparing the TM data in the mid-1990s with new data sources received during 1999-2000 and 1989-1990. The LUCC database has supported greatly the national LUCC research program in China and some relative studies are incompletely reviewed in this paper.  相似文献   

14.
土地利用/土地覆被变化研究:寻求新的综合途径   总被引:198,自引:26,他引:198  
蔡运龙 《地理研究》2001,20(6):645-652
土地利用/土地覆被变化是很复杂的现象,参与该项目的研究人员要避免“瞎子摸大象”那样的片面性,必须寻求新的综合研究途径。为此,不能简单地沿袭传统土地利用研究的思路和方法,需要不断提出新的研究论题;对土地利用变化驱动力必须有一种普遍的、综合的认识;需要将多个案例研究联结为一个可代表区域空间异质性的网络,需要作多空间尺度的研究,从而将地方尺度和区域尺度的土地覆被动态联系起来;需要发展新的研究方法,并将从农户调查到遥感数据的各种信息综合起来;尤其需要形成关于土地利用/土地覆被变化的综合科学理论框架  相似文献   

15.

Describing and explaining land-use change is of critical concern in Madagascar, where land transformations such as deforestation and resulting environmental degradation currently capture widespread attention. While the eastern rain forest recedes in the face of swidden cultivators, the highlands demonstrate more constructive transformations. In this paper I present a case study of land-use change in Leimavo, a small village near Ambositra studied in the 1960s by Jean-Pierre Raison. Here, the twentieth century has seen a gradual reduction in irrigated rice cultivation and cattle husbandry, and a boom in market-oriented orange, vegetable, and grain production. In the long term, a historical landscape of grassy hills has been transformed into a productive cultural landscape with woodlots, anti-erosion benching, rice terraces, fruit groves, and diverse crops. Critical factors determining the trajectory of land-use change include regional population pressure, state policies, market incentives, climate variations, and access to land and water resources. These critical factors, or explanations, are linked in the discussion by the use of a simple heuristic device—the range of choice—as a theoretical framework.  相似文献   

16.
中国西部干旱区土地利用变化显著,是全球土地变化科学研究的热点区,为此论文基于1990—2016年4个时段的遥感卫星数据,采用面向对象的分层分类影像解译方法完成了塔里木盆地南缘和田地区(简称和田塔里木地区)土地利用调查,重点分析土地利用变化特征、发展模式和区域差异性。结果表明:1990—2016年,和田塔里木地区耕地持续加速扩张(增长率为2.9%/a),呈现渐进式扩张和骤变式开垦2种发展模式;建设用地面积增加(12.1%/a),主要表现为城市化发展、农村居民用地和交通用地的增加;耕地和建设用地扩张导致林灌草地和未利用地面积减少;和田地区县域土地利用发展不均衡,和田市建设用地比例最高,和田县与墨玉县的农业和建设用地扩张总量和速率最大,其次是洛浦县和于田县,皮山县、策勒县和民丰县农业和建设用地增长相对缓慢;总体上,和田塔里木地区耕地和建设用地的扩张在新疆处于一个较快的发展水平,今后一段时期快速的土地利用变化可能引起的生态环境问题需要重点关注。  相似文献   

17.
Describing and explaining land-use change is of critical concern in Madagascar, where land transformations such as deforestation and resulting environmental degradation currently capture widespread attention. While the eastern rain forest recedes in the face of swidden cultivators, the highlands demonstrate more constructive transformations. In this paper I present a case study of land-use change in Leimavo, a small village near Ambositra studied in the 1960s by Jean-Pierre Raison. Here, the twentieth century has seen a gradual reduction in irrigated rice cultivation and cattle husbandry, and a boom in market-oriented orange, vegetable, and grain production. In the long term, a historical landscape of grassy hills has been transformed into a productive cultural landscape with woodlots, anti-erosion benching, rice terraces, fruit groves, and diverse crops. Critical factors determining the trajectory of land-use change include regional population pressure, state policies, market incentives, climate variations, and access to land and water resources. These critical factors, or explanations, are linked in the discussion by the use of a simple heuristic device—the range of choice—as a theoretical framework.  相似文献   

18.
基于数理统计的快速城市化时期土地利用变化分析试以土地系统理论为基础,运用数理统计方法,建立1996—2005年各类用地数量变化数据库,分析大连市各类用地时空变化规律,预测未来用地规模。采用吉布斯一马丁(Gibbs—Mirtin)多样化指数和洛伦兹(Lorenz)曲线分析大连市各类用地的数量结构特点,利用二次指数平滑方法预测出2010~2020年大连市各类用地规模。结果表明,1996年以来全市建设用地面积呈上升趋势,农业用地和未利用地面积呈缓慢下降态势,但就经济增长的规模看,未来大连的经济发展不会始终保持之前的增长态势,建设用地的需求量也将有所缩减。  相似文献   

19.
局地土地利用变化现实情景研究   总被引:4,自引:0,他引:4  
局地土地利用变化表现为时序短、空间倾向性强且多为人类强制干扰, 其变化过程与结果 是区域尺度响应与反馈国家尺度、全球尺度最有效的途径。城市化、农业结构调整和土地整理是 目前我国局地土地利用变化的几种主要利用方式。城市化是一个不可逆过程, 农村景观转为城市 景观, 改变了诸如地表反照率、粗糙度等下垫面特征, 局地生境与物种的数量与种类发生改变, 逐 步形成以人类为主的均质化景观格局; 农户微观土地利用选择行为是局地农业产业结构调整的 原动力, 不同类型农户在投资、生产与经营等经济活动的差异将导致局地土壤结构、水分、养分等 土壤条件及环境改变; 土地整理是一个复杂的系统工程, 在一定程度上改变了局地土壤性状与土 壤生物, 更甚的是改变了局地斑块- 廊道- 基质模式的景观格局。因此, 为进一步加深局地土地利 用变化情景的理解, 厘定“人- 地协调系统”的理论框架, 进行局地土地利用变化的情景模拟和生 态环境效应研究将是未来局地土地利用变化的研究方向。  相似文献   

20.
20世纪90年代中国土地利用变化时空特征及其成因分析   总被引:358,自引:38,他引:320  
在土地利用变化时空信息平台的支持下,本文对我国20世纪80年代末到90年代末的土地利用变化过程进行了全面分析,揭示了我国10年来土地利用变化的时空规律,分析了这些规律形成的主要政策、经济和自然成因。研究表明,20世纪90年代,全国耕地总面积呈北增南减、总量增加的趋势,增量主要来自对北方草地和林地的开垦。林业用地面积呈现总体减少的趋势,减少的林地主要分布于传统林区,南方水热充沛区造林效果明显。中国城乡建设用地整体上表现为持续扩张的态势。90年代后5年总体增速减缓,西部增速加快。20世纪90年代我国的土地利用变化表现出明显的时空差异,政策调控和经济驱动是导致土地利用变化及其时空差异的主要原因。据此,本文提出在今后的全国土地利用规划中,应充分考虑我国现代土地利用变化的区域分异规律。同时,在生态环境恢复与建设规划中也应强调自然地理地带的针对性,同时要改变传统的资源规划与管理思路,在基础设施日益完备的条件下,最大程度地发挥跨区域土地资源优化配置的综合优势  相似文献   

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