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1.
Rapid land use change has taken place in many arid and semi-arid regions of China including the Loess Plateau. In this study, changes in land use and landscape fragmentation in the small Shanghuang watershed on the Loess Plateau were investigated by the combined use of remote sensing, GIS and landscape metrics. Land use classes were mapped and analyzed from a time series of maps and remotely sensed images that were ground truthed in 2008. Analyses of the data showed that land use had undergone substantial changes in this small watershed from 1982 to 2008, and these changes could be divided into three phases according to the change in the landscape matrix whereby the dominant land use was grassland (1982–1990), cropland (1990–2002) and forestland (2002–2008). During each phase, conversions between different land use types took place frequently, especially among cropland, orchards, grassland and forestland. Landscape fragmentation increased from 1982 to 1990 and then decreased from 1990 to 2008 as indicated by four landscape metrics. These changes in land use and landscape fragmentation in this small watershed were mainly controlled by human factors (land management, construction, population pressure, and government policy) rather than natural factors.  相似文献   

2.
GIS and RS techniques have been applied to interpret satellite data in 1992, 2000 and 2010. Further, the ecological environment factors of these three periods and the data for various types of land use have been obtained. LUDI in the Amur River Basin from 1992 to 2010 has been quantitatively analyzed by using the land use dynamic (LUDI) model and of land use transfer matrix model. The results indicated that from 1992 to 2010 the LUDI of land desertification is greatest, and is the most dramatic change. The comprehensive land use dynamic in the study area is 15.25, hence the land type is characterized by rapid change. In addition the area of woodland and farmland continues to increase, which has been mainly transformed from the mixture of forestland and grassland, marsh and wetland, this is an outcome of the production of shelter-forest plantation in North China, Northeast China and Northwest China. In the ten years period of the study, the area of desertified land has increased, changing mainly from a mixture of woodland and grassland. This study can rovide data for eco-geological environment management.  相似文献   

3.
徐倩  李阳兵  黄娟 《中国岩溶》2018,37(4):545-554
选取贵州省清镇市近郊村域王家寨地区为研究对象,在GIS支持下,利用该区域1963年、1982年、2005年、2010年和2015年5期土地利用图形数据叠加分析,提取出研究区50余年来的土地利用/覆盖信息,并结合相应的社会经济统计数据,分析了其驱动力因子,其结果表明:(1)1963—2015年间,土地覆盖类型的总体变化为高被草地和平坝旱耕地明显减少,低被草地、农村居民点、工矿用地、公路用地面积大幅增加,其中,平坝旱耕地有向经济效益更高的土地利用方式转变的趋势;(2)景观格局演变的总体趋势是:自1963年起,斑块数量、斑块密度持续增加,到2015年呈下降趋势,而最大斑块指数逐年减小,形状趋于不规则,同时,近50年景观的多样性指数持续增加;(3)区内土地利用/覆盖和景观格局呈阶段性变化,从1963年到2005年,坡地土地利用活动较强,2005年后,平地土地利用强度增加、农业逐渐转型、聚落持续扩展;(4)区内土地利用及景观格局的变化主要受经济、人口和政策因素的影响。   相似文献   

4.
Based on the Landsat TM data in 1988 and 2002, the GIS technique and Fragstats software were used to calculate the land use conversion matrix and eight landscape metrics at landscape and patch class levels in upstream, midstream, and downstream regions of Nenjiang River basin. The characteristics of land use and landscape pattern changes in each region during 1988–2002 were analyzed. The results show the followings: 1) During the period from 1988 to 2002, farmland and construction land area increased, while the areas of forestland, grassland, and unutilized land decreased in all three regions. The conversion trends from forestland and grassland to farmland were obvious. The conversion from forestland to farmland mainly occurred in the upstream region, whereas the conversion from grassland to farmland primarily occurred in the midstream and downstream regions. 2) The water area in the upstream and midstream regions enlarged, mainly due to the increase of water impounded area as a result of the construction of reservoirs. Comparatively, the water area in the downstream region decreased, and it mainly occurred in the east part of downstream region with concentrated lakes and swamps. 3) The degree of landscape fragmentation increased in each region. The controlling ability of forestland was weakened, and its patch shape became more complicated. In contrast, the controlling ability of farmland was reinforced, and the connectivity among patches increased. 4) The landscape pattern shows some gradient features. From the upstream to downstream regions, the disturbance of human activities on dominant patches was intensified, and consequently, the landscape fragmentation extent and heterogeneity were enhanced.  相似文献   

5.
资源型城市景观生态风险的时空分异:以乌海市为例   总被引:1,自引:0,他引:1  
为探究大型露天煤矿开采对西北干旱荒漠区景观生态风险的影响,以及资源型城市转型背景下的时空动态,以资源衰退型的内蒙古自治区乌海市及周边县域为研究区,结合现有景观生态风险评价中的干扰度、脆弱度指标,增加受威胁指数来综合构建资源型城市景观生态风险评价框架。基于乌海市2005—2015年景观类型数据,从时间和空间上分析景观生态风险及其动态。结果显示:(1)2010—2015年景观类型之间转移相较于2005—2010年更剧烈,年变化强度分别为7.43%和3.44%,工矿用地与城市建设用地最活跃,但年增加强度减小。(2)林地、水域和湿地损失度先略增加后大幅度减小,其他土地和草地损失度呈增加趋势,工矿用地先减小后略增加;城市建设用地和工矿用地受威胁指数最大,其余类型的景观受威胁指数均有上升趋势,但其他土地、水域和湿地增加趋势逐渐减慢。(3)2005—2015年景观生态风险指数升高,空间分布总体呈西、中部高而南北低的格局,而不同等级风险区表现为低风险区由边缘向中心转移,而高风险区依托原有高风险区扩展。研究期风险区变化显著的是西部沙地高风险区,矿区东部其他土地因周围分布灌丛和草地,风险始终低于西部其他土地。根据不同风险等级中工矿用地的面积占比情况,将工矿用地占比控制在5%以内可达到控制总体景观生态风险的目的。研究为资源型城市通过合理的景观配置进行生态风险管控提供了依据。  相似文献   

6.
以陕西省千阳县作为研究区,提取2000~2015年的遥感数据为基础,参照土地利用程度指数、景观指数和数学模型,分析了景观格局的变化特征;根据生态系统服务价值的评估模型,定量分析了千阳县景观格局的变化对生态系统服务价值(ESV)的影响.结果表明,2000~2015年,千阳县农耕面积逐年减少,转变为草地和林地,未利用土地转...  相似文献   

7.
Understanding the ecological mechanisms and processes driving changes in our landscapes is significant for ecological conservation. This work used remote sensing with the extending contingency-based method to quantify the interchange relationship of land use types, and landscape metrics including spatially nuanced difference at patch level to track immigrants’ resettlement impacts at the semi-arid Hongsipu region with decadal agricultural pumping irrigation development in Ning Xia, China. Landsat-TM images acquired in 1989, 1999, 2003, and 2008 were used to study landscape changes in three periods, the earlier development from 1989 to 1999, the middle period in 1999–2003, and final stage in 2003–2008. The results showed the over 50 % landscape area experienced drastic change in each period with heavy immigrants’ perturbations since 1998. The nearly natural landscape with 1:1 area between desert and steppe in 1989 10 years before development, however, became the overwhelming barren landscape with almost 80 % of the study area in 2008, grassland and shrub land almost disappeared respectively, and cultivated land climbed to the third large type from about 2 % in 1989 to more than 16 % in 2008. The landscape became more fragmented, more regular shape with human disturbance spreading from the northwest low mountain and flat basin to the southeast diluvial fan, even high mountain at the end. Although Hongsipu pumping irrigation zone alleviates poor population pressure in the fragile ecological southern mountainous areas of Ningxia, the new artificial oasis creates another possible new ecological risk of the study area. Therefore, besides the economic development, the ecological conservation and restoration measures should be also the primary objectives in order to successful resettlement immigrants.  相似文献   

8.
黑河上游土地利用动态变化及影响因素的定量分析   总被引:9,自引:4,他引:5  
由于特殊的自然地理属性和人类活动方式, 西北干旱区黑河上游的土地利用方式有别于中下游地区, 土地利用格局演变过程对全流域水资源和生态环境的影响巨大.以黑河上游为研究对象, 以1987年, 1999年和2010年的遥感影像为基础数据, 运用转移矩阵法和主成分分析等方法定量分析了林地、 草地、 耕地3种主要土地利用类型的动态变化过程, 揭示了其变化的动力机制.结果表明: 1)黑河上游土地利用变化阶段明显, 林地、 草地和耕地3种土地利用类型在1987-1999年和1999-2010年两个阶段转化显著, 林地持续减少, 草地先减少后增加, 耕地持续增加; 2)单一土地类型分布格局差异大, 林地呈东多西少, 北多南少的分布格局; 草地呈东多西少, 南多北少格局; 耕地集中分布于河谷和城镇居民点周围及山前地带; 3)人为因素是影响黑河上游土地利用动态变化的关键因素.  相似文献   

9.
为了更好地了解贵州省毕节地区生态系统类型的构成、格局与转化特征,本文基于面向对象分类和空间统计与分析技术,对毕节地区2000年和2010年生态系统类型进行提取,并对生态系统构成、格局和转化特征进行定量分析。结果表明:从生态系统构成和格局看,2010年研究区生态系统类型以林地和耕地为主,分别占研究区面积的42.65 %和42.51 %;2000和2010年该区均具有较高的斑块数和较小的平均斑块面积,说明该地区景观破碎化程度较高;2010年斑块总数较2000有所减少,表明研究区景观连通性得到改善,景观整体趋于规整化;2010年旱地斑块总面积和平均斑块面积有所减少,针叶林、草地则增加,显示该地区退耕还林还草项目的实施有所成效;旱地和针叶林的聚集度都增加,表明二者连通性增强、景观更加集中。从生态系统转化特征看,2000-2010年,研究区生态系统类型间转化总面积为1 298.25 km2,面积明显减少的是旱地和水田,明显增加的主要为林地、草地,土地面积转移矩阵显示旱地主要向林地、草地转化;受旱地面积较大影响,毕节、黔西、大方的面积变化和生态系统转化剧烈程度都较大,8个县(市)的生态系统类型相互转化强度值均为正值,可见生态系统覆被类型均向着较好的方向发展。   相似文献   

10.
生态安全条件下亚洲沙区土地利用结构研究   总被引:7,自引:0,他引:7  
基于数字地图与遥感影像资料,通过分析土地利用格局与沙尘传输关系,研究了生态安全条件下土地利用结构优化的模式、方法与技术。研究表明:①亚洲生态安全条件下的土地利用/覆盖宏观三圈格局为: 内圈以自然保护为主的沙漠地带;中圈以建设人工草地为主,辅以大面积自然恢复的草原地带;外圈以农、林、牧复合为主的交错地带。中国处在宏观三圈格局的中东部,北方沙区是影响东亚沙尘暴的重要源区。②中国半干旱沙区土地利用呈现微观三圈模式,基于RS数据,依据“大面积搞生态,小面积搞生产”的原则进行的土地利用结构优化,提出了外圈沙丘地恢复天然草地生态用地——中圈草原地带大面积搞生态—小面积搞牧业生产——内圈甸子地高效农业生产用地的生态—生产范式。③典型区科尔沁沙地土地利用结构优化的成套技术,可为类似地区政府土地利用决策与生态补偿机制提供支持。  相似文献   

11.
Rapid land-use change has taken place in many arid and semi-arid regions of China over the last decade as the result of demand for food for its growing population. The Heihe River Basin, a typical inland river basin of temperate arid zone in northwestern China, was investigated to assess land-use change dynamics by the combined use of satellite remote sensing and geographical information systems (GIS), and to explore the interaction between these changes and the environment. Images were classified into six land-use types: cropland, forestland, grassland, water, urban or built-up land, and barren land. The objectives were to assess and analyze landscape change of land use/cover in Heihe River Basin over 15 years from 1987 to 2002. The results show that (1) grassland and barren land increase greatly by 22.3, and 268.2 km2, respectively, but water area decreased rapidly by 247.2 km2 in the upper reaches of Heihe River Basin; (2) cropland and urban or built-up land increased greatly by 174.9, and 64.6 km2, respectively, but grassland decreased rapidly by 210.3 km2 in the middle reaches of Heihe River Basin; and (3) barren land increased largely by 397.4 km2, but grassland degraded seriously and water area decreased obviously by 313.3, and 21.7 km2, respectively in the lower reaches of Heihe River Basin. These results show that significant changes in land-use occur within the whole basin over the study period and cause severe environmental degradation, such as water environmental changes (including surface water runoff change, decline of groundwater table and degeneration of surface water and groundwater quality), land desertification and salinization, and vegetation degeneracy.  相似文献   

12.
采用新疆喀什噶尔河流域1990、2000和2010年的Landsat-TM影像数据和中巴资源卫星数据, 结合GIS技术, 分析了喀什噶尔河流域近20 a土地利用/覆被及景观格局动态变化特征, 并对其变化原因进行探讨. 结果显示: 在1990-2010年喀什噶尔河流域耕地、建设用地、盐碱地、水域湿地、裸土地和其他未利用地面积呈不断增加趋势, 变化幅度分别为73.92%、51.44%、24.27%、10.24%、6.47%和2.98%; 林地、草地和沙地面积减少, 变化幅度分别为-4.13%、-17.16%和-0.73%; 裸石岩砾面积近20 a基本维持不变. 利用转移矩阵可知, 流域新增耕地面积主要来自于16.46%的草地和3.36%的林地; 新增建设用地主要来自于1.46%的耕地和0.22%的草地; 新增水域湿地面积主要来自于0.18%的草地; 新增盐碱地面积主要来自于0.28%的草地. 1990-2010年的20 a里喀什噶尔河流域耕地和水域湿地分布趋于集中, 景观优势度增强, 且斑块之间的联系不断增强. 林地和草地面积减少, 景观趋于破碎化, 景观优势度降低. 喀什噶尔河流域土地利用类型及景观指数的变化受人口、经济、政策和技术的多重影响, 导致流域耕地面积增加、植被退化. 因此, 合理利用流域水土资源对流域生态环境安全十分重要.  相似文献   

13.
淮河流域作为我国重要的粮食产地,其水资源利用情况具有很高的研究价值。利用MODIS蒸散发数据产品(MOD16/ET)、降水和气温时序数据以及土地利用数据,探讨了淮河流域2000—2014年蒸散量时空变化特征及其对气候变化、土地利用的响应。结果表明:淮河流域蒸散量在空间上表现为南高北低,蒸散量多年均值为589.1 mm,夏季最高,冬季最低。整体而言,淮河流域15年间蒸散量具有先增加后减少的趋势;趋势分析结果显示,31.4%的地区蒸散量呈显著或极显著减少趋势,5.4%的地区蒸散量呈显著或极显著增加趋势,63.2%的地区蒸散量无显著变化。从蒸散量的气候因子分区看,52.0%的区域表现为非气候因子驱动型,44.1%的地区为降水驱动型,双因子驱动型和气温驱动型范围很小,面积占比分别为2.4%、1.5%,表明人类活动对蒸散发的影响巨大。四种植被覆盖土地利用蒸散量均值表现为林地>水田>旱地>草地。根据2000—2014年土地利用转变引起蒸散量变化的统计结果,草地转变为水田时蒸散量明显增加,旱地转变为草地、林地转变为旱地后蒸散量明显减少。  相似文献   

14.
【研究目的】 基于1990—2018年间的土地利用空间分布数据、数字高程模型(Digital Elevation Model,DEM)、植被、气象等数据,对位于东北地区自然资源时空变化及其区域生态环境效应进行定量分析。【研究方法】 按照东北地区自然-地理-资源分布规律,通过定量计算与定性分析相结合的区划分析手段,将研究区划分为7个二级自然资源亚区和14个三级自然资源地区,分析其近30年来(1990—2018年)自然资源时空动态特征及生态环境效应。【研究结果】 结果表明:(1)近30年,研究区最主要的变化是森林、草地转变为耕地、水体与湿地,同时大量耕地被开发为建设用地,以及草地的荒漠化现象较突出。这与当地的老工业基地振兴政策、强农惠农政策等关系紧密。(2)研究区整体生态环境质量呈下降趋势,尤其是I1、I5、I6、I7二级亚区(I1三江平原温带耕地亚区、I5小兴安岭山地温带森林亚区、I6山前平原温带耕地亚区和I7松辽平原温带草耕亚区)。(3)森林、草地转变为耕地,大量面积的草地荒漠化等变化类型,对研究区生态环境质量恶化的生态贡献率较大。【结论】 近30年,研究区大量森林、草地转变为耕地和水体与湿地,大量耕地被开发为建设用地以及草地荒漠化加剧,其I1、I5、I6、I7二级亚区生态环境质量下降趋势较显著,森林、草地转变为耕地以及草地荒漠化等变化类型对此现象的生态贡献率较大。  相似文献   

15.
The mechanism of interaction between land use change and landscape pattern is pivotal in research concerning global environmental change. Quantitative evaluation of land use change that has resulted from excessive land development and its impact on landscape pattern are important for sustainable utilization of local land resources. The study area was the Manas River watershed, a typical watershed in an arid area. The present study evaluated the influence of long-term land use change on the landscape pattern; the findings are valuable for economic development and environmental protection. The processes for land use change and changes in landscape pattern were reconstructed and analyzed for data in topographic maps dated 1962 and in remote sensing images taken in 1976, 1989, 1999 and 2008 using mathematical models and landscape metrics. The results indicate significant changes in land use over the past 50 years, with increases in the areas of cultivated land and construction land, and a significant decrease in unused land and woodland areas; grassland and water resources first increased and then tended to decrease over this time. The comprehensive index of land use change is 0.55, indicating an unbalanced, one-way transition in the study area. Landscape fragmentation and diversity increased and landscape dominance decreased; in other words, differences between landscapes decreased. The changes resulted in a significant tendency toward diversity and fragmentation of the landscape. Therefore, large-scale intensive agricultural development can reduce the negative influence of land use change on the landscape pattern.  相似文献   

16.
为研究中国西南地区自然资源的动态变化特征,基于中国自然资源综合区划一级分区成果,以西南林耕自然资源大区为研究对象,通过选取符合区域特征的要素指标,确定指标权重,按照区划方案对西南林耕自然资源大区进行二级、三级区划,将其划分为6个自然资源亚区(二级区划)和11个自然资源地区(三级区划),并对区划单元内的自然资源动态变化进行了特征分析。研究区内自然资源以森林、耕地和草原为主,1990—2018年,自然资源变化主要表现为森林、耕地和草原三者间的相互转变,森林和耕地之间的相互转变主要分布于贵州和重庆的地区,森林和草原、耕地和草原之间的相互转变主要分布于云南和陕西的地区。建设用地明显增加,集中分布于各省会城市和直辖市。各类资源相互之间有明显转变,但面积在总体上基本保持动态平衡,表明自然资源的转变在合理范围内,其中四川盆地内的耕地和广西西部的森林受保护较好。各区划内优势资源明显,区划间变化特征彼此相异,可为全国或西南地区的自然资源配置、国土空间规划等自然资源统一管理提供决策支撑。  相似文献   

17.
基于分区—分层—分波段方法,对贵州省大方县1988年、2001年、2009年三期TM影像进行土地利用类型分类,并对其时空变化规律进行分析。结果表明:三个时间段内耕地既有扩张也有缩减,但总体面积减少,减少幅度为33%;林地扩张范围大于退缩范围,总体面积增加,增加幅度为34%;草地面积先减少后增加,空间格局变化剧烈,总体减幅为11%;建设用地数量上持续扩张,增幅比例最大,增幅达715%。总体而言,人类活动是影响大方县土地利用数量和空间格局变化的主要原因,海拔和坡度等自然因素对耕地、林地的扩张和退缩有明显影响。   相似文献   

18.
2005-2015年贵阳市生境退化程度对土地利用变化的响应   总被引:1,自引:1,他引:0  
基于2005和2015年贵阳市土地利用数据,利用InVEST模型,分析了2005-2015年贵阳市生境退化程度对土地利用变化的响应,结果表明:(1)2005-2015年贵阳市城镇建设用地、农村居民点和有林地大幅增加,水田和旱地大幅下降,其他地类变化相对较小;水田和旱地转化为城镇建设用地、农村居民点和有林地最为突出;(2)10年间,贵阳市生境退化程度以下降为主,生境退化程度增加区主要分布在南部,下降区主要分布在北部、东部和西部;(3)生境退化程度热点变化以低值减少和高值减少为主;生境退化程度热点空间变化主要分布于南部。退耕还林政策及快速城镇化引起的水田和旱地转化为有林地、城镇建设用地和农村居民点是导致该区生境退化程度变化的主要因素。   相似文献   

19.
应用RS、GIS以及GPS集成技术,以黔中喀斯特地区的猫跳河流域为对象,研究了这一地区从1973—2002年间土地利用/覆被的变化过程,并利用典型相关分析法研究了形成这种变化的驱动因素。研究表明,从1973—1990年,猫跳河流域耕地、建设用地、有林地、水域以及裸岩地呈增长趋势,而灌木林和灌草地趋于减少,流域生态环境质量下降。进入20世纪90年代后,有林地、灌草地、建设用地、水域持续增加,灌草地总量变化不大,耕地总量和裸岩地减少,流域生态环境质量趋于好转。定量分析表明,1990年以前,驱动建设用地变化的因素是总人口的变化,1990年以后则是农业产值;1990年以前驱动耕地变化的是农业人口的增长,1990年以后则和粮食产量的提高有关。   相似文献   

20.
霍林河流域下游地区土地利用变化动态及趋势预测   总被引:6,自引:0,他引:6  
霍林河流域下游地区为半农半牧区,土地利用的变化对该地区的生态环境会产生重大的影响。采用空间分析测算模型,揭示了1989~2001年期间该地区土地利用的空间变化特征以及土地利用类型三减(草地、水体、湿地)两增(耕地和未利用土地)的变化规律;并通过马尔可夫模型预测出未来24年内该区土地利用类型的演变趋势,得出水田、旱田、林地、城乡用地的继续增加是以草地、水域、湿地的减少为代价的结论,对生态环境的保护和土地资源的合理利用具有参考价值。  相似文献   

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