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1.
Loss and degradation of terrestrial and aquatic habitats and degraded water quality are major environmental concerns worldwide. Especially wetlands are sensitive ecosystems that are subject to stress from human activities. Remote sensing techniques have been primarily used to generate information on land cover/use changes. Geographical Information Systems (GIS) and remote sensing can be used to provide a rapid or a large-scale understanding of lake change and in developing lake management strategies. The principal objectives of this study are to monitor and assess the spatial and temporal changes in land cover/use by using GIS, and to determine the main environmental factors affecting these changes. This paper presents a case study for the application of integrated remote sensing and GIS data for the classification and monitoring of the spatial and temporal changes in land use types. The study was conducted in a small natural wetland of Lake Cheimaditida, located in the East Mediterranean region of Northern Greece. Data analysis was conducted using GIS software. During the past several decades Lake Cheimaditida wetland has been influenced by many anthropogenic activities. The variables chosen for the assessment included condition of wetland and lake areas, present extent of wetlands relative to historic area, cover of natural habitat, wetland disturbances, etc. These variables address catchments properties that are important for maintaining and improving wetland habitats and water quality and assessment of trends useful for environmental monitoring. Land cover/land use patterns were assessed and compared using aerial photographs taken in 1945, 1969, 1982, and 1996. Over this period, reed beds enormously increased by 1,655.19%, while open-water areas and peat lands decreased by 74.05 and 99.5%, respectively. The significance of the changes in land cover distribution within the Lake Cheimaditida wetland are discussed in relation to the historical pattern of reed beds colonization, the importance of Phragmites australis in the process and the implications for strategic management of freshwater wetland resources.  相似文献   

2.
Management and planning of the natural environment requires spatially accurate and timely information on land use patterns. With repetitive satellite coverage, the rapid evolution of computer technology and the integration of satellite and spatial data, the development of land use applications have become ubiquitous. The integration of Remote Sensing (RS) and Geographic Information Systems (GIS) has been widely applied and recognized as a powerful and effective tool in detecting land use change in urban areas. This paper presents the land use change analysis of the Beykoz region, which is the second largest administrative district of Istanbul. Land use changes and their impacts are monitored using Landsat (MSS - TM) and Spot 5 satellite data in the period of 1975-2001. The independent classification of each satellite image was used as a change analysis method and the resulting images were analyzed with GIS techniques. The results showed that forest area of Beykoz decreased from 80.55% to 70.5% between 1975 and 1984 and during the 1984-2001 periods, the forested area decreased from 70.5% to 68.86% and the urban growth rate was 4.65%.  相似文献   

3.
Lake Pamvotis, NW Greece is a shallow Mediterranean eutrophic lake that has changed drastically over the past 50 years. Strong effects, resulted mainly from anthropogenic causes, in the hydrological regime are shown for this area using long term hydrological data and a GIS system for extracting land cover/use changes. A set of aerial imagery acquired in 1945 through 2002 were used to monitor and assess the spatial and temporal changes in land cover/use, focused mainly on the lake’s surface area and its surrounding ecosystem (Natura 2000 area). The significance of the changes in land cover/use distribution within Pamvotis wetland is further discussed depicting the role of the anthropogenic influence on the fragile ecosystem that resulted in the shrinkage of lake’s habitats extent. The purpose of this analysis was to examine the long-term changes on macrophyte community composition, species occurrence and relative abundance with water quality and water level changes over the past century, using historical data, aerial photos and GIS techniques. The results showed that for the last 25 years annual water level fluctuation ranged from 70 to 159 cm. Water level starts decreasing in mid June and increasing again gradually from November until March–April. Intra annual water level fluctuation seems to be affected by land use for agricultural purpose through intensive irrigation and the summer drought as well. A dramatic decline of the submerged vegetation is apparent mainly attributed to anthropogenic pressures. Regarding the land cover/use changes, the most notable and significant alterations are concerning the urban development around the lake, the disappearance of wet meadows and the extension of reed beds. Finally it seems that water budget data as well as the response of the key eutrophication parameters are affected from both hydrological alterations and point/non-point pollution sources.  相似文献   

4.
通过利用遥感、地理信息系统相结合的技术方法,解译万州区2000年与2004年2期遥感影像,获得该地区相关数据的矢量图及定量统计数据,结合万州区自身特点,运用包含4个指数在内的指标分析了土地利用和土地覆盖变化(LUCC)特征,为该区土地的合理利用提供决策依据。结果表明:土地整体变化不大,单一动态度则各有千秋,其中较为明显的是建设用地增长突出,以及林地和耕地的减少,因此为实现该区可持续发展,必须采取措施保护耕地和林地,加强城市建设用地的管理。  相似文献   

5.
Efficient natural resources management, including continental water at watershed level, requires understanding the arrangement of landscape attributes in a region. The geographical analysis of landscape attributes is a useful approach to delineate relatively homogeneous watersheds or regions. This research was carried out in order to evaluate the effect of land cover through time on regionalisation modelling in the poorly-gauged Cuitzeo Lake Watershed, and to develop models to create two hydrogeographical regionalisations for the years 1975 and 2000. The inputs required by the regionalisation methodology were integrated in a GIS and validated before carrying out statistical regionalisation procedures (cluster analysis and PCA). GIS operations were done in Arc View 3.2 and statistical analyses in PC-ORD. Median Euclidean distances with mean distance linkage methods were used. A 75% of similarity was chosen as the threshold to generate regions. Importance rankings of regions were obtained using multicriteria evaluation methods. Based on the analysis, 38 of the 52 subwatersheds belonging to the Cuitzeo Lake Watershed were clustered; eight groups were defined in 1975 and nine in 2000. According to PCA, the strongest positive variables are associated to morphometric, geologic, land cover and soil attributes. Fourteen subwatersheds were never clustered. Four subwatersheds changed of cluster between 1975 and 2000. This change is explained because of rainfed agricultural parcel abandonment, and subsequent shrubland growth. This means that the hydrogeographical regionalisation is sensitive to land cover change processes. The methodological approach applied in this research is a low-cost and fast alternative for evaluating the impact of land cover and land use change on hydrogeographical regionalisation; in consequence, data and information generated during the analysis were made available to local authorities so that they can improve both water resources planning and their informational baseline for decision making and for development of environmental policies in the Cuitzeo Lake Watershed.  相似文献   

6.
嘉陵江流域土地利用/覆被变化特征及其驱动力分析   总被引:1,自引:0,他引:1  
在GIS技术平台上,通过建立指数模型,对嘉陵江流域1980,1995和2000年3个时期的土地利用/覆被时空变化特征进行了定量研究,并进一步分析了嘉陵江流域土地利用/覆被变化的驱动因素。结果表明:研究区土地利用类型以耕地、林地和草地为主,这3种植被类型之间的相互转化是流域土地利用/覆被变化的主要方式。自1980—2000年,耕地和林地面积先减少后略有增加,草地先增加后减少,建设用地逐年增加,其他地类变化不明显。分析表明,嘉陵江流域土地利用/覆被变化的驱动力主要为自然因素、经济因素、人口因素及宏观政策和工程建设,各因素之间相互影响和制约,共同影响流域土地利用格局的变化。  相似文献   

7.
以2000—2015年的遥感影像资料和生态输水数据为基础数据源,利用ENVI和GIS数据分析处理工具,基于时间轨迹分析方法研究塔里木河下游土地利用/覆被变化(LUCC)对生态输水的响应。结果表明:2000—2015年的16次、1 670 d间歇性生态输水,使林地和草地分别增加了823个和1 347个像元,耕地、湿地和人工用地分别减少了1 422个、736个和222个像元,其他用地增加了210个像元;植被面积总体上呈扩大趋势,2015年较2000年净增植被面积382.85 km2,人工表面增加356.10 km2;戈壁、裸土、沙漠等其他用地面积共计减少了738.95 km2;土地利用变化主要发生在塔里木河下游两岸的河水漫溢、滞留区,呈现出破碎化、不规则化和复杂化的趋势。  相似文献   

8.
The present study was conducted using secondary database, remote sensing, geographical information system (GIS) and multivariate analysis tools in order to develop Multiple Linear Regression (MLR) models that could be able to predict level of water quality variables using compositional and spatial attributes of land cover in the river basins. The study encompasses 21 river basins with 32 000 Km2 area, located in the Chugoku district in West Japan. Biological Oxygen Demand (BOD), pH, Dissolved Oxygen (DO), Suspended Solid (SS), Total Nitrogen (TN), and Total Phosphorus (TP) were considered as water quality variables of the stream. Satellite data was used to generate the land cover map of the study area. MLR models were developed using the compositional (%) and spatial attributes (landscape metrics) of the land cover at watershed and class levels for representing the land cover-stream water quality linkage. The results of the MLR modeling using the land cover data at the class level revealed that 92%, 74% and 62% of the total variations in concentration of DO, pH and TP were explained by changes in the measure of the spatial attributes of the land cover at the class level in the study area. These models can help local and regional land managers to understand the relationships between the compositional attribute (%) and the spatial features of the land cover and river water quality and would be applied in formulating plan for watershed-level management.  相似文献   

9.
通过遥感(RS)技术获得的土地利用时间序列信息,分析杞麓湖流域土地利用的动态变化以及未来发展趋势。以杞麓湖流域1988年、1996年、2006年、2016年4期Landsat遥感数据为基础,在遥感与地理信息系统(GIS)技术支持下,遥感解译获取4个时段土地利用类型图,结合空间格局、转移矩阵、动态度、利用程度、空间重心,分析了该区域1988—2016年期间土地利用变化特征及其驱动机制。结果表明:空间格局上,林地变化最多,耕地次之,并且大部分耕地转化为建筑用地,其他用地不断向耕地、林地转化;土地利用重心不断向北发展,说明北部经济及其城镇化发展比南部快;方位变化表明该区域西部发展前期大于东部。最后通过驱动机制分析,发现社会经济因素是该区域土地利用变化的主要驱动因素,并且驱动作用不断扩张。研究成果可为该区土地利用可持续发展提供科学依据。  相似文献   

10.
以陆浑水库控制流域为研究对象,利用流域DEM、土地利用数据、1987—2001年气候和水文观测数据,在率定SWAT模型参数的基础上,以SCS模型参数的变化来反映覆被变化,分析了未来气候变化情景及覆被变化情景对径流的影响。结果表明:2011—2050年在流域落叶林地面积退化30%情况下径流量将增大7.02%,落叶林地面积增加20%情况下径流量将减少8.48%。  相似文献   

11.
结合高分辨遥感影像和GIS数据的土地利用变化监测   总被引:1,自引:1,他引:0  
研究了一种结合高分辨率遥感影像和GIS数据的土地利用自动变化监测方法。分别采用马氏距离、支持向量机、神经网络3种分类方法对研究区域进行模糊分类,然后通过多分类器模糊决策融合分类方法对3种分类结果进行融合,提高总体分类精度。在获得高精度分类结果的基础上,结合历史时期GIS专题数据和分类结果,计算对应的图斑多边形内各类别成份,并与其历史属性对比分析,自动实现土地利用变化监测。实验数据选取QuickBird高分辨率遥感影像和1∶1万土地利用GIS数据,实验结果表明模糊决策融合分类能够明显改善分类效果,获得比单一分类器更为精准的结果。利用决策分类结果并结合GIS数据进行变化区域判定实验,结果表明,对区域中存在较大变化能够准确自动判定为变化区域,而区域中存在较少部分变化则存在部分误判现象。  相似文献   

12.
Integrated watershed management requires a host of inter-related information to be generated and studied in relation to each other. Remote sensing technique provides valuable and up-to-date spatial information on natural resources and physical terrain parameters. Geographical Information System (GIS) with its capability of integration and analysis of spatial, aspatial, multi-layered information obtained in a wide variety of formats both from remote sensing and other conventional sources has proved to be an effective tool in planning for watershed development. In this study, area and locale specific watershed development plans were generated for Mayurakshi watershed, India using remote sensing and GIS techniques. Adopting Integrated Mission for Sustainable Development (IMSD) guidelines, decision rules were framed. Using the overlay and decision tree concepts water resource development plan was generated. Indian Remote Sensing Satellite (IRS-1C), Linear Imaging Self Scanner (LISS-III) satellite data along with other field and collateral data on lithology, soil, slope, well inventory, fracture have been utilized for generating land use/land cover and hydro geomorphology of the study area, which are an essential prerequisites for water resources planning and development. Spatial data integration and analyses are carried out in GIS environment.  相似文献   

13.
阿穆尔河流域水环境变化条件下,运用GIS和RS技术,对阿穆尔河流域的2期NOAA影像数据和1期MO-DIS影像数据进行解译判读,获取不同时期阿穆尔河流域湿地与生态要素数据,为研究区的生态地质环境治理提供数据依据。通过动态度模型和转移矩阵模型,对研究区1992年-2010年间的湿地与生态的动态变化情况进行了量化的分析。结果表明:1992年-2010年18a间,沙化土地的动态度最大,为15.25,属于急剧变化型,沼泽和湿地面积大面积减少,林草混杂地面积减少,沼泽、湿地、林草和混杂地快速转化为林地和耕地,在近10a间,沙化土地面积又有增加趋势,主要转入类型为林地和草地混杂地。  相似文献   

14.
A comparative study of probabilistic frequency ratio (FR) and weights of evidence (WofE) method is performed for delineation of regional groundwater potential zones (GPZ) in canal command system. In the present case study, delineation of GPZ in the Hirakud agricultural command area of Odisha, India. Field discharge data from borewells are utilized for the analysis along with remote sensing (RS) and geographic information system (GIS) techniques. Various influencing attributes responsible for occurrence and movement of groundwater, e.g., land use / land cover, soil type, groundwater depth, geology, elevation, geomorphology, slope, recharge rate, rainfall, normalized difference vegetation index, drainage density, crop intensity are integrated by using GIS platform. Model results from FR and WofE show similar trends. The middle portion of the study area covers the ‘Good’ GPZ. Sensitivity analyses are performed for FR and WofE methods.  相似文献   

15.
通过建立泾河流域SWAT分布式水文模型,重点模拟分析了河流径流情势对土地利用/覆被变化的响应,对比了不同气候条件及人类活动综合影响下研究区水文过程的变化。结果表明:1996年以前土地利用/覆被变化是影响水文过程的主要人类活动影响源,径流量年际变化平稳,属有小幅增加的正偏;年内影响以枯水季节为主,年内分配更趋均匀,径流集中度降低,集中期略有滞后,且趋于平稳;土地利用/覆被变化导致流域蒸散发量、冠层和落叶层截留量减小,入渗量增加,河川基流量和地表径流量相应增大,并在时域上耦合形成了水文过程的新变化;1996年以后,气候条件驱动下泾河年径流量呈现明显的增大趋势,人类活动亦从以土地利用/覆被变化为主转变为以人类水事活动为主的综合影响模式,且人类水事活动超过气候变化和土地利用/覆被变化成为影响水文过程变化的主因。  相似文献   

16.
This study provides one historical and two alternative future contexts for evaluating land cover modifications within the Upper Mississippi River (UMR) floodplain. Given previously documented changes in land use, river engineering, restoration efforts and hydro‐climatic changes within the UMR basin and floodplain, we wanted to know which of these changes are the most important determinants of current and projected future floodplain land cover. We used Geographic Information System data covering approximately 37% of the UMR floodplain (3232 km2) for ca 1890 (pre‐lock and dam) and three contemporary periods (1975, 1989 and 2000) across which river restoration actions have increased and hydro‐climatic changes have occurred. We further developed two 50‐year future scenarios from the spatially dependent land cover transitions that occurred from 1975 to 1989 (scenario A) and from 1989 to 2000 (scenario B) using Markov models. Land cover composition of the UMR did not change significantly from 1975 to 2000, indicating that current land cover continues to reflect historical modifications that support agricultural production and commercial navigation despite some floodplain restoration efforts and variation in river discharge. Projected future land cover composition based on scenario A was not significantly different from the land cover for 1975, 1989 or 2000 but was different from the land cover of scenario B, which was also different from all other periods. Scenario B forecasts transition of some forest and marsh habitat to open water by the year 2050 for some portions of the northern river and projects that some agricultural lands will transition to open water in the southern portion of the river. Future floodplain management and restoration planning efforts in the UMR should consider the potential consequences of continued shifts in hydro‐climatic conditions that may occur as a result of climate change and the potential effects on floodplain land cover. Published 2011. This article is a U.S. Government work and is in the public domain in the USA.  相似文献   

17.
借助RS和GIS技术,对方正县1995和2005年Landsat TM遥感影像进行处理,在获取土地利用数据的基础上,分析土地利用现状及时空变化。结果表明,土地利用结构相对简单,以农、林业用地为主;未利用地、草地和耕地耗减度较大;居民工矿用地的开发度最大,其次是草地和耕地,该分析结果可为该区域的土地利用的可持续利用提供有效的决策支持。  相似文献   

18.
基于LandsatTM/ETM+、CBERS-02B CCD遥感影像数据,运用RS和GIS技术对二滩库区1995年以来的土地利用/覆盖进行分类研究,对二滩库区13年来的土地利用/覆盖变化情况及驱动力进行了分析。结果表明:1995~2008年间,二滩库区耕地面积明显减少,林地、草地和水域面积明显增加,建设用地面积变化不大;其中林地和草地面积的增加与1998年、1999年两大林业生态工程——天然林资源保护工程、退耕还林(草)工程的相继实施以及二滩水库蓄水后对库区局地气候的调节作用有关。  相似文献   

19.
基于RS和GIS的三峡库区水土流失动态监测研究   总被引:13,自引:1,他引:12  
 介绍了利用遥感和地理信息系统栅格技术进行三峡库区水土流失动态监测的过程和方法。首 先利用遥感图像处理软件ERDAS进行了土地利用的分类和植被覆盖度的计算,然后利用地理 信息系统软件ARC/INFO中GRID工具进行各类水土流失因素图的空间分析,估算各县或小流 域的水土流失强度,并计算各种强度下的水土流失面积。  相似文献   

20.
Land use/land cover changes in a lake drainage basin reflect changes in the magnitude of the water balance components and rate of sediment deposition in a lake as a reflection of the fundamental linkage between what happens in a lake considered against what is happening in the drainage basin of the lake. The objective of this study was to quantify the spatio‐temporal land cover/land use changes across the Lake Hayq 1 1 Lake Hayq is also locally called Lego.
closed drainage basin in north‐east Ethiopia over a 50‐years period, using multitemporal remote sensing and geospatial data. Two historical occasions of aerial photographs (1957 and 1986) and one satellite image (2007) were examined with image analysis tools: Leica Photogrammetric Suite (LPS 9.2) Project Manager, ArcGIS10.0, and ERDAS EMAGINE 9.2. Seven aerial coverage of land use/land cover categories were identified and mapped for the past three historical times. The results indicated that farmlands/settlements and shrublands/degraded lands increased by 43.1% and 136.9%, at an annual rate of 27.4 and 13.5 ha year?1, respectively, between 1957 and 2007. In contrast, bushlands, grasslands, forestlands and lake surface area were diminished by 68.8%, 62.7%, 90.5% and 7.6%, at a rate of 24.0, 7.6, 6.1 and 3.7 ha year?1, respectively, over the past five decades. The basin had undergone significant transformation in land use/land cover over the past half century, affecting the lake's biophysical stability by accelerating soil erosion in the basin, sediment accumulation, and a reduced quantity and quality of cumulative stream flow into the lake.  相似文献   

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