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1.
1980-2000年中国LUCC对气候变化的响应   总被引:10,自引:0,他引:10  
高志强  刘纪远 《地理学报》2006,61(8):865-872
基于中国1980~2000年气候数据及两期土地利用/土地覆盖 (LUCC) 数据,利用Holdridge 植被生态分区模型、重心模型及土地利用程度模型,分析气候变化及人类活动对中国植被覆盖及土地利用的影响程度及变化趋势。1980~2000年间,中国大部分地区温度升高,降水增多。气候变化不仅影响了中国植被群落分区,更进一步影响了植被群落的生长状况;东北、华北、内蒙古高原等区域未利用土地型向草地和灌木生态类型转换,草地和灌木型生态类型向林地和耕地型转换;又因为1980~2000年间中国经济的发展,东部沿海区域城市乡村建设用地及交通用地的增多,使土地利用类型由农业耕地型向建设用地型发展,导致土地利用程度指数的升高。气候变化及经济发展的双重作用,导致中国土地利用程度重心20年来向东北方向移动了54 km,东西方向土地利用程度偏移强度,气候占81%,人类活动占19%,南北方向土地利用程度偏移强度,气候占85%,人类活动占15%。  相似文献   

2.
Sudden and gradual land use changes can result in different socio-ecological systems, sometimes referred to as regime shifts. The Lao PDR (Laos) has been reported to show early signs of such regime shifts in land systems with potentially major socio-ecological implications. However, given the complex mosaic of different land systems, including shifting cultivation, such changes are not easily assessed using traditional land cover data. Moreover, regime shifts in land systems are difficult to simulate with traditional land cover modelling approaches. A novel simulation approach was employed that focused on simulating changes in land systems rather than focusing on land cover. With the CLUmondo model we simulated three scenarios of potential developments between the years 2010 and 2030 assuming different degrees of international market integration and sustainable growth objectives. Although all scenarios show a decline of shifting cultivation systems, the respective orientation of markets and land governance resulted in strongly different land change trajectories. The land system changes are strongly location dependent and different trajectories are found in different parts of the country. Some scenarios show clear elements of land sparing with intensification of land management in the valleys and re-growth of forest on sloping land. Other scenarios show elements of enhanced multi-functionality. The approach addressed methodological challenges in simulating land system regime shifts and complex mosaic landscapes while accounting for societal demands for different types of goods and services from land systems. The land systems approach allows a nuanced representation of different types of forests and agricultural systems such as shifting cultivation and commercial agricultural plantations. Simulation results contribute to a debate about desired future land use on the national scale including its environmental and socio-economic implications.  相似文献   

3.
张雪艳  吴世新 《中国沙漠》2006,26(2):208-214
应用遥感和地理信息系统等技术手段,获取了天山北麓阜康三工河地区1968年、1978年、1988年、2002年的荒漠化土地时空分布及各时段土地荒漠化动态变化数据,并对其荒漠化过程进行了空间统计分析。结果表明:34 a来,三工河地区土地荒漠化以盐渍化为主、沙漠化及水土流失次之;荒漠化土地面积具有前期逐渐增加,20世纪80年代末以后面积大幅度减少的趋势;土地盐渍化变化主要发生在绿洲内部,土地沙漠化变化主要发生在绿洲外围,而严重的水土流失主要发生在山区;土地荒漠化的动态变化与土地利用/土地覆被变化及生态系统的管理方式有着密切关系。  相似文献   

4.
1974-2011年白洋淀土地覆盖时空变化特征   总被引:1,自引:0,他引:1  
在野外调查的基础上,运用遥感和地理信息系统技术对1974年、1979年、1984年、1987年、1989年、1991年、1996年、2001年、2006年和2011年10期遥感影像进行解译和分析,揭示了白洋淀近37年土地覆盖动态变化。结果表明:近37年白洋淀土地覆盖类型变化极为复杂,主要表现为水体、芦苇地、耕地3种土地覆盖类型相互转化。1974-2011年,水体面积从58.01 km2上升到80.07 km2,芦苇地面积从104.94 km2下降到72.95 km2,水生植被从14.02 km2下降到4.27 km2。1974-2011年,耕地、水体、芦苇地、居民点转化为其它类型的比例相对较小,分别为39.25%、34.46%、53.74%和18.15%。水体面积增加主要分布在地势较低的东部和北部地区,水体面积减少主要分布在地势较高的西南地区。水位变化、入淀径流量变化、淀区气候变化、人类活动及管理政策是白洋淀土地覆盖变化的驱动因子。研究揭示了白洋淀土地覆盖与人类活动的相互作用关系,对白洋淀土地管理和生态系统服务可持续供给具有重要意义。  相似文献   

5.
Rapid urbanization leads to losses in arable land; quantitatively analyzing the impact of urbanization on arable land is significant for arable land management. However, changes in arable land due to urbanization with scale and neighborhood effects remains poorly understood at the town scale. In this study, high-resolution historical land use data, landscape metric analysis and spatial regression were integrated to quantify the impacts of urbanization on arable land use change (abandonment and conversion) at spatial scales of 300 m–3300 m using a block size increment of 200 m and at the catchment scale in the town of Jinjing in subtropical central China. Arable land abandonment was the predominant type of arable land change and presented strong spatial autocorrelations at each spatial scale. Arable land was converted to tea fields because agricultural structure transformations were occurring around the urban cores, and the amount of arable land converted to residential land accounted for only a small proportion of the total arable land loss and had no spatial autocorrelation. The significance and robustness of the arable land changes impacted by urbanization had obvious scale effects and strong neighborhood effects in nearby regions. Compared with block scales, the catchment scale is an optimal scale for assessing the influence of urbanization and applying planning policy. Our results highlight the significance of incorporating spatial interactions in urbanization research, which can generate less biased estimations and consequently lead to proper policy implication and recommendations. In addition, multi-scale comparisons are helpful for better understanding the relationships between arable land changes and urbanization and provide further insights into the harmonious development of rural settlements and urban cores to preserve arable land.  相似文献   

6.
Ecosystem services are premises for human beings to exist and develop in the world, and it is of importance to study effects of land use change on ecosystem functions. Songnen plain, located in Northeast China, is one of the national key bases for agricultural production. Because there were remarkable variations in land use in recent years, it can supply specific foundation for protection and restoration of regional eco-environment to explore changes in its values of ecosystem services. This study aims to qualify long-term changes in land use of Songnen plain from 1980 to 2000, and to explore the impact of land use change on ecosystem services. With 2-period land use data using RS and GIS, this paper analyzed changes in land use and in ecosystem service values using the ecosystem service value coefficients (VC) put forward by Costanza et al. Results showed that from 1980 to 2000, area of rangeland, water area and wetlands and area of cropland decreased, but urban area and unused land increased. Due to cropland's comparatively low VC and comparatively high VC of wetlands and water area, increment in cultivated land could not offset the total decrement in regional ecosystem service values because of the decrease in area of wetlands and water area. Meanwhile, city sprawl has also led to loss of ecological values. Total ecosystem service values of the study area reduced dramatically, from 34,926.10×106$ to 31,744.54×106$ in the period 1980-2000. This represents a 9.11% net decline in annual value of ecosystem services in the study area.  相似文献   

7.
Based on digital land use data from 1995 to 2000 and road data, the land use and landscape changes of Golmud, Qumaleb and Zhidoi are studied on a macro-scale. Land use and landscape changes in highway buffer zones and city expansion are special subjects. A new formula is used to define the exact degree of dynamic land use. To adequately define land use and landscape pattern changes, the buffer zones, illustrating the changes at different distances from the road, are recognized with ArcGIS 8.1 software. Prominent changes took place in land use and landscape patterns from 1995 to 2000, and the area of built-up land increased by 323.8%. The comprehensive degree of dynamic land use is 2.25, and the degree of dynamic land use of built-up land is the highest, followed by cultivated land. Woodland has the lowest value. The used degree index of land resources declined by 38.8 from 1995 to 2000. Landscape changed dramatically which influenced ecological processes immensely. Different from the corridor effect of other traffic routes, the corridor effect of this section of road is not obvious and its “point” radiation effect can be easily seen. The expanding range of Golmud City is confined to a 3 km buffer, while for Wudaoliang, it is 1 km. No land use change happened in the Nanshankou buffer.  相似文献   

8.
Based on digital land use data from 1995 to 2000 and road data, the land use and landscape changes of Golmud, Qumaleb and Zhidoi are studied on a macro-scale. Land use and landscape changes in highway buffer zones and city expansion are special subjects. A new formula is used to define the exact degree of dynamic land use. To adequately define land use and landscape pattern changes, the buffer zones, illustrating the changes at different distances from the road, are recognized with ArcGIS 8.1 software. Prominent changes took place in land use and landscape patterns from 1995 to 2000, and the area of built-up land increased by 323.8%. The comprehensive degree of dynamic land use is 2.25, and the degree of dynamic land use of built-up land is the highest, followed by cultivated land. Woodland has the lowest value. The used degree index of land resources declined by 38.8 from 1995 to 2000. Landscape changed dramatically which influenced ecological processes immensely. Different from the corridor effect of other traffic routes, the corridor effect of this section of road is not obvious and its "point" radiation effect can be easily seen. The expanding range of Golmud City is confined to a 3 km buffer, while for Wudaoliang, it is 1 km. No land use change happened in the Nanshankou buffer.  相似文献   

9.
深圳土地利用时空变化与地形因子的关系研究   总被引:5,自引:0,他引:5  
引入GIS空间分析和数字地形模型(DEM)技术,利用土地利用数据和地形数据,定量分析土地利用时空变化与地形因子的关系,从土地利用空间分布、土地利用转移和土地利用变化速度3方面总结地形因子对深圳土地利用时空变化的影响特征及规律。结果表明:在深圳土地利用时空变化过程中,地形因子对土地利用变化的影响作用明显,在不同地形级别上土地利用分布、土地利用转移和土地利用变化速度等均表现出不同的时空变化特征。  相似文献   

10.
拉萨地区土地利用变化   总被引:11,自引:0,他引:11  
除多  张镱锂  郑度 《地理学报》2006,61(10):1075-1083
根据1990年、1995年和2000年3期西藏拉萨地区土地利用现状调查数据,利用GIS空间分析方法,系统地分析了1990年至2000年间拉萨地区的土地利用时空变化特征。得出: ① 10年来拉萨地区的土地利用类型转变主要发生在人类活动比较集中的城镇附近和河谷地区,很多地段的天然植被由人工植被所取代,植被覆盖度和生物产量明显提高,有效地改善了这些区域的土地覆盖状况,这些变化是这一期间实施的农业综合开发中旨在改变区域生态环境的人工植树造林和改良草场等人为有目的地改变土地利用类型的直接结果;② 10年内面积增幅最大的是林地,增加了2.56%;③ 土地利用类型变化最广泛的是牧草地,由牧草地变成耕地、园地、林地、居民点及水域的,其中牧草地变成林地的面积最大,占变化面积的94.09%;④ 耕地变成林地的面积占耕地移出总量的54.86%,变成居民点的占移出面积的38.25%;⑤ 水域变成林地的面积占变化面积的93.13%。  相似文献   

11.
1992-2015年中亚五国土地覆盖与蒸散发变化   总被引:8,自引:0,他引:8  
阮宏威  于静洁 《地理学报》2019,74(7):1292-1304
1991年苏联解体,中亚五国独立使得土地覆盖与蒸散发格局发生深刻变化。以中亚五国为研究区,采用欧空局气候变化项目(CCI)土地覆盖和全球陆地数据同化系统(GLDAS)蒸散发数据,分析1992-2015年土地覆盖与蒸散发时空变化特征,进一步研究耕地蒸散耗水特征。结果表明:① 中亚五国土地覆盖变化具有阶段性特征,耕地扩张引起土地覆盖格局变化。1992-2003年耕地快速增加(1.1万km 2/a),林地和草地大幅减少。2003-2015年耕地增速趋缓(0.3万km 2/a),林地和草地有一定恢复,裸地和水体持续减少,城镇用地持续增长。耕地共增加12.3万km 2,林地和草地分别减少4.0万km 2和2.3万km 2,且集中于哈萨克斯坦中北部。裸地减少3.5万km 2,集中于哈萨克斯坦西南部,水体减少3.1万km 2,集中在咸海湖泊。乌兹别克斯坦耕地减少、裸地增加,吉尔吉斯斯坦、塔吉克斯坦和土库曼斯坦土地覆盖变化幅度较小;② 中亚五国蒸散发变化与土地覆盖格局基本一致。蒸散发总体呈增加态势(6 mm/a),1992-2003年快速增加(11.3 mm/a),2003-2015年缓慢上升(2.4 mm/a)。中亚五国年蒸散发达到276.8 mm,东南部的吉尔吉斯斯坦(347.3 mm)和塔吉克斯坦(302.9 mm)最高,中北部的哈萨克斯坦(297.9 mm)次之,西南部的乌兹别克斯坦(211.0 mm)和土库曼斯坦(150.0 mm)最低;③ 中亚五国蒸散耗水结构受耕地面积大小的影响。中亚五国耕地蒸散耗水的贡献由24.7%增至27.9%,土库曼斯坦耕地蒸散耗水仅占本国的11%,其他国家均超过25%。草地、林地和裸地的蒸散耗水贡献降低,但哈萨克斯坦、吉尔吉斯斯坦和塔吉克斯坦仍以草地和林地蒸散耗水为主(≥ 50%),土库曼斯坦(61.3%)和乌兹别克斯坦(46.4%)的裸地蒸散耗水占绝对优势。本文明确了中亚五国土地覆盖连续动态变化过程,细化各国土地覆盖与蒸散发特征及差异,增强对土地覆盖与蒸散发现状的认识,可为水土资源管理和生态环境保护提供数据参考。  相似文献   

12.
During the past 50 years forests have recolonized extensive areas of Puerto Rico. Between 1950 and 1990 forest cover increased from 9% to 37% of the island's land area. In proportional terms more land has reverted to forest in Puerto Rico than anywhere else on earth during the second half of the twentieth century. This paper explores the geography of this process by matching changes in land cover with the characteristics of the land and communities in Puerto Rico. The reversion of agricultural lands to forest occurred most frequently in humid, upland, coffee-growing regions characterized by heavy out-migration and populations of smallholders who earned some of their income from off-farm sources. These findings suggest that changes in non-farm labor markets, as well as changes in the political economy of agriculture, have important impacts on the prospects for converting agricultural lands into forests.  相似文献   

13.
Mountaintop removal mining is a dominant driver of land use/land cover changes in the Appalachian Region of the eastern United States and is expected to increase in scale in the coming decades. While several studies quantify land use/land cover changes attributed to traditional surface mining and at regional scales, no studies we are aware of focus specifically on mountaintop removal/valley fill mining practices at the watershed scale. Further, despite its scale and extent, its impact on runoff, particularly at larger spatial scales (103 km2), is poorly understood due to the complex relationships between climate, land use, and hydrology. To explore the impacts of this practice at broader scales, we estimated land use/land cover changes using Landsat 5 TM imagery over five periods between 1994 and 2010; used a simple rainfall–runoff model to estimate hydrologic response time; and conducted non-parametric trend analyses on annual hydrologic metrics (streamflow, Q/P, response time) for the Big Coal River watershed located in the southern West Virginia coalfields. No statistically significant trends were detected in any of the timeseries. The lack of detectable trends and correlations between land use changes and hydrology at the basin scale are not entirely unexpected due to the history and mosaic of land cover changes that span timescales larger than our study period. Further interannual variation likely overwhelms our ability to detect potential changes using monotonic trend analysis at the annual time scale, particularly in light of strong streamflow seasonality. Future studies therefore should include different methods of change detection applied to different timescales to more appropriately account seasonal and interannual variations. Until the significance of this practice on water resources (quality and quality) are understood, efforts to reduce the environmental problems associated with mountaintop mining will be difficult to achieve.  相似文献   

14.
为分析地表覆被变化的水文效应,以半分布式的地形指数模型 (TOPOMODEL) 为基础,对梭磨河流域1960~1999年逐日流量过程进行了模拟。结果表明,对于流域面积2536km2 的梭磨河流域,该模型也能取得较好的模拟结果。模拟了流域40年来气候波动和地表覆被变化对流域水文的影响。最后在4种不同的流域土地覆被情景下模拟了1960~1999年逐日径流过程。对于实际蒸散发与潜在蒸发有300多mm差距的梭磨河流域,在其它条件不变的情况下,随着流域土地覆被和冠层最大截流量的增加,冠层截流蒸发和流域总蒸发增加,植被蒸腾和土壤表面蒸发减少,土壤水分增加而流域水分含量和饱和层含水量减少。地表径流、地表以下径流、总径流减小。重现期小于20年的洪峰流量减小,但对40年一遇的洪峰流量影响很小,甚至有增加洪峰流量的作用。  相似文献   

15.
This study evaluates land use/cover changes and urban expansion in Greater Dhaka, Bangladesh, between 1975 and 2003 using satellite images and socio-economic data. Spatial and temporal dynamics of land use/cover changes were quantified using three Landsat images, a supervised classification algorithm and the post-classification change detection technique in GIS. Accuracy of the Landsat-derived land use/cover maps ranged from 85 to 90%. The analysis revealed that substantial growth of built-up areas in Greater Dhaka over the study period resulted significant decrease in the area of water bodies, cultivated land, vegetation and wetlands. Urban land expansion has been largely driven by elevation, population growth and economic development. Rapid urban expansion through infilling of low-lying areas and clearing of vegetation resulted in a wide range of environmental impacts, including habitat quality. As reliable and current data are lacking for Bangladesh, the land use maps produced in this study will contribute to both the development of sustainable urban land use planning decisions and also for forecasting possible future changes in growth patterns.  相似文献   

16.
以佛山南海区为例,采用遥感、土地利用调查及土地利用现状图等多种数据,运用遥感影像人机交互解译、景观格局指数以及田野调查、案例分析等定量与定性相结合的方法,分析了1987年以来南海区土地利用时空变化及其对土地产权变革的响应。结果发现,南海区土地产权变化分为3个阶段:即土地有偿投包制阶段(1987-1992年)、土地股份合作制阶段(1993-2002年)和土地紧缩及“三旧”改造政策下的政府主导模式阶段(2003-2013年),这3个阶段土地产权的演化具有以土地的“所有”为中心向以“利用”为其中心转变的趋势,这是市场需求和资源利用高效化发展的结果,也是土地由资源转变为资产及资本的过程。南海区土地产权变化与土地利用时空变化具有较为显著的关联性及规律性。土地利用在不同时段变化的速度、强度和结构等对土地产权变化的响应明显,其空间格局也同样呈现“农用地集聚-乡村工业化破碎格局-集聚与破碎化共存”3个阶段性变化特征。南海区土地利用变化是众多内外部因素综合作用的结果,主要表现为诱致机制、引导机制、引擎机制及调节机制。宏观上,土地股份制改革和分散的管理体系导致了土地利用的粗放扩张和破碎化格局;微观上,不同土地利用主体间的利益博弈、土地收益分配方式及产权割裂是导致土地利用变化的根本原因。未来经济转型与土地再开发过程中,如何针对土地产权变化新趋势,兼顾各利益相关方的诉求,构建利益共享机制是实现土地高效利用和空间优化的关键。  相似文献   

17.
刘晓宇  辛良杰 《地理研究》2022,41(6):1637-1651
土地价格是城市综合发展水平的反映,厘清中国城市土地价格的时空演变特征及其成因,有助于从宏观上把握地区间的发展差异。本文以地级行政区为研究对象,系统分析2007—2019年中国332个城市综合土地价格和住宅、商服、工矿仓储用地价格的演变特征及驱动因素,主要结论如下:① 2007—2019年间中国城市综合地价呈现显著的上涨趋势,由2007年的392.34元/m2上升至2019年的1357.31元/m2,年均增长80.73元/m2;地价水平在空间上呈现“东南高,西北低”的格局。② 三种主要地类的价格及增速高低依次为:住宅用地>商服用地>工矿仓储用地,发展逐渐分化,差距不断扩大。③ 不同等级城市的土地价格逐渐分化为三类:高速增长型(一线城市)、平稳增长型(新一线城市和二线城市)和缓慢增长型(三线城市、四线城市和五线城市),呈现出明显的“马太效应”。④ 人均地区生产总值、人口密度和普通中小学学校数越高的城市,各类土地价格越高;本地人均地区生产总值、第二产业占比和第三产业占比越高的城市,其相邻城市的住宅和商服地价越高,工矿仓储地价越低。  相似文献   

18.
吴箐  李宇 《地理科学》2014,34(6):705-710
土地利用变化对生物多样性和生态过程有着深刻的影响,与城乡景观格局变化密切相关。尝试将土地利用变化驱动力——土地经济生态位的理论和方法引入到景观生态学当中,为城乡空间景观格局空间表征提供新的方法。通过选取表征景观格局指标的破碎化指数、分形维数,利用Envi4.8、Arcmap10.0,Fragstasts4.1等软件,以广东省惠州市为例,在分析土地经济生态位与景观类型、景观指数之间的关系基础上,对土地经济生态位变化下的城乡空间景观格局进行表征。结果表明:不同景观土地面积数量的增减与该类型土地经济生态位升降具有一致性的规律,土地经济生态位上升,相应的景观土地面积增大,反之则减小;土地经济生态位越小,表征景观格局的景观破碎化指数、分维数指数越大,破碎化指数与分维数指数的增减与土地经济生态位升降表现出一致性的规律,土地经济生态位上升,相应的破碎化指数、分维数指数则增大,反之则减小;城乡空间景观格局变化的发生主要出现在土地经济生态位高的区域。土地经济生态位的变化是城乡景观格局变化的重要影响因子,能够很好解释城乡空间景观格局特征。  相似文献   

19.
Nowadays,spatial simulation on land use patterns is one of the key contents of LUCC.Modeling is an important tool for simulating land use patterns due to its ability to inte-grate measurements of changes in land cover and the associated drivers.The conventional regression model can only analyze the correlation between land use types and driving factors, but cannot depict the spatial autocorrelation characteristics.Land uses in Yongding County, which is located in the typical karst mountain areas in northwes...  相似文献   

20.
19802000北京市农业土地生产性的变动分析   总被引:1,自引:0,他引:1  
王鹏飞  鲁奇  傅桦  李娟 《地理研究》2006,25(4):719-729
根据1980、1990、2000年的统计资料和实地走访观察,本文分析了北京市乡镇一级的粮食作物、蔬菜作物和果品作物的分布格局及农业土地生产性近20年的变化。研究认为:1980年北京农业生产分布格局与土地生产性为比较典型的杜能模式;随着农业经营的多样化,1990年和2000年北京农业土地生产性呈现出多样的分布格局;北京粮食作物、蔬菜作物、果品作物的分布格局及农业土地生产性近20年的变化与此阶段的农业生产政策、农业以外的社会经济活动变化有较强的关联性;对北京以上问题的研究为验证杜能、辛克利亚、布莱昂特城市周边农业地域研究经典理论的演变提供了实证案例。  相似文献   

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