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海河流域水土流失微地貌测量与分析 总被引：1，自引：0，他引：1
介绍了国外引进的3D激光地貌分析仪的组成及技术指标.在海河流域水土流失区进行水土流失微地貌测量,获取了数据,并就地表高度、坡度、典型剖面和粗糙度等方面分析了仪器的先进性,提出了设备引进和实地测量中需要注意的问题. 相似文献
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《国土资源遥感》2021,(3)
生态敏感性是生态系统对自然环境变化和人类活动干扰的敏感程度,可以反映生态环境问题发生的难易程度和可能性大小。以黄土丘陵沟壑区延河流域为例,选取水土流失敏感性指数、生态风险敏感性指数和生物多样性敏感性指数3个定量评价指标,基于空间距离指数构建流域综合生态敏感性指数(comprehensive ecological sensitivity index,CESI),并结合重心模型探讨1996—2016年间延河流域生态敏感性的时空变化情况。研究结果表明:(1)从时间变化来看,延河流域生态敏感性总体呈下降趋势,CESI由1996年的1.38上升到2016年的1.41,表明延河流域生态环境质量有所改善;(2)从空间分布变化看,延河流域1996—2016年间生态敏感性空间分布情况变化较大,1996年生态敏感性较高地区集中在延河流域上游部分,2006年以后生态敏感性较高地区主要分布在延河流域中游及下游的部分地区;(3)1996—2016年,延河流域各级生态敏感性区域重心向延河流域中游转移,生态敏感性分布由1996年的集中分布转为2016年的集中与分散相结合的分布情况;(4)延河流域生态敏感性受土地利用方式影响较大,延河流域"退耕还林(草)"工程及综合治理工程在生态敏感性转好过程中起关键作用。 相似文献
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《现代测绘》2015,(5)
在前人已有的土地利用/覆盖变化研究的基础上,应用美国农业部水土保持局研制的SCS(Soil Conservation Service)模型,对海河流域1980和2008年正常土壤湿度下的地表径流进行模拟计算,分析了近29年来海河流域城镇化对地表径流的影响,同时也验证了SCS模型应用于较大流域进行地表径流模拟计算的可行性。研究结果表明,海河流域城市扩张基本上都是建立在占用耕地基础上的。因城市扩张导致城市建筑用地大面积增加、耕地大面积减少而引起的流域不透水面积增多是致使流域地表径流深度增加的直接原因。城市地表径流增加与城市扩张变化是有直接关系的:城市扩张速度越快的地区地表径流深度增长也相对较快。同时,植树造林对强降雨条件下地表径流增加具有一定抑制作用。 相似文献
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滦河流域从1990年就被列为国家级水土流失重点防治区,国家在水土流失治理方面进行了大力投入。进入21世纪,通过大规模的治理,流域水土流失得到了有效遏止,生态环境明显好转。与此同时,国家在该区域开展了多次土壤侵蚀遥感调查,调查结果在时间上形成序列,客观反映了流域的水土流失状况及其变化趋势。在历次土壤侵蚀调查结果的基础上,对滦河流域从1984～2008年近三个年代的土壤侵蚀时空变化进行分析,确定了流域内水土流失强度在空间和等级的变化情况。 相似文献
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何芷 《测绘与空间地理信息》2018,(7):187-191
以江西省赣州市为例,利用通用水土流失方程,对该地区进行土地脆弱性分析和评价。讨论了研究区域的土地侵蚀脆弱性的高低分布特征以及其在不同因素作用下的土壤侵蚀空间分异特征。分析结果表明:1)中部和周边部分地区土壤侵蚀最低,这部分地区多位于山区、丘陵等海拔相对较高区域,同时也是降雨量相对较少的区域。2)以人类活动,沿赣州市的道路网分布为空间分布规则,在其邻域内土地的脆弱性依次增高,以道路网和工业区、农业区为最高,向周边区域逐渐递减,说明人类活动对土壤侵蚀的控制措施影响巨大。3)水土流失方程理论中的降雨量、地形等因素是土壤脆弱性变化的潜在因素,而人类活动是土地侵蚀发生、发展、变得严重的主导因素。 相似文献
8.
基于GIS的小流域水土流失遥感定量监测研究 总被引：14，自引：1，他引：14
以三峡库区典型小流域为研究区域，通过遥感和野外调查进行信息采集．建立了流域环境数据库；在GIS支持下，根据修正通用土壤流失方程（RUSLE）模型对数据库实施运算操作，探讨了流域内土壤侵蚀强度的空间分布规律，并估算了小流域水土流失量。 相似文献
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This study integrates the RUSLE, remote sensing and GIS to assess soil loss and identify sensitive areas to soil erosion in the Nilufer creek watershed in Bursa province, Turkey. The annual average soil loss was generated separately for years 1984 and 2011, in order to expose possible soil loss differences occurred in 27 years. In addition, sediment accumulation and sediment yield of the studied watershed was also predicted and discussed. The results indicated that very severe erosion risk areas in 1984 was 13.4% of the area, but it was increased to 15.3% by the year 2011, which needs immediate attention from soil conservation point of view. Furthermore, the estimated annual sediment yield of the Nilufer creek watershed was increased from 903 to 979 Mg km?2 y?1 in 27 years period. The study also provides useful information for decision-makers and planners to take appropriate land management practices in the area. 相似文献
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Javed Mallick Yasser Alashker Shams Al-Deen Mohammad Mohd Ahmed Mohd Abul Hasan 《国际地球制图》2013,28(8):915-940
Soil erosion is the most important factor in land degradation and influences desertification in semi-arid areas. A comprehensive methodology that integrates revised universal soil loss equation (RUSLE) model and GIS was adopted to determine the soil erosion risk (SER) in semi-arid Aseer region, Saudi Arabia. Geoenvironmental factors viz. rainfall (R), soil erodibility (K), slope (LS), cover management and practice factors were computed to determine their effects on average annual soil loss. The high potential soil erosion, resulting from high denuded slope, devoid of vegetation cover and high intensity rainfall, is located towards the north western part of the study area. The analysis is investigated that the SER over the vegetation cover including dense vegetation, sparse vegetation and bushes increases with the higher altitude and higher slope angle. The erosion maps generated with RUSLE integrated with GIS can serve as effective inputs in deriving strategies for land planning/management in the environmentally sensitive mountainous areas. 相似文献
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Soil erosion is one of the major causes of land degradation in arid areas. Soil erosion models, e.g. the revised universal soil loss equation (RUSLE), use arithmetical expressions to explore relationships among various processes occurring in the terrain. The established model includes soil parameters, slope, climate and human activities to estimate the water erosion rate and sediment yield. In this study, an approach was adopted to integrate RUSLE model and geographic information system to detect erosion vulnerability and determine the soil erosion risk in the study area. The study area is situated in the Eastern Desert, Egypt. Ground truth data were examined to represent two regions: Luxor-Suhag and Suhag–ElMinya. These regions are exampled by four dry valleys named Sannor, Tarfa, Asyut and Qena, which are planned for agricultural development. The results indicate high risk of water erosion and sediment load discharge into the cultivated land in Luxor–Suhag region. The other region of Suhag–ElMinya is moderately affected by water and sediment load discharge. A higher soil erosion rate was found in Qena wadi followed by Asyut, then Tarfa and Sannur, respectively. 相似文献
14.
Soil erosion prediction based on land cover dynamics at the Semenyih watershed in Malaysia using LTM and USLE models 总被引：1，自引：0，他引：1
This study attempts to identify and forecast future land cover (LC) by using the Land Transformation Model (LTM), which considers pixel changes in the past and makes predictions using influential spatial features. LTM applies the Artificial Neural Networks algorithm) in conducting the analysis. In line with these objectives, two satellite images (Spot 5 acquired in 2004 and 2010) were classified using the Maximum Likelihood method for the change detection analysis. Consequently, LC maps from 2004 to 2010 with six classes (forest, agriculture, oil palm cultivations, open area, urban, and water bodies) were generated from the test area. A prediction was made on the actual soil erosion and the soil erosion rate using the Universal Soil Loss Equation (USLE) combined with remote sensing and GIS in the Semenyih watershed for 2004 and 2010 and projected to 2016. Actual and potential soil erosion maps from 2004 to 2010 and projected to 2016 were eventually generated. The results of the LC change detections indicated that three major changes were predicted from 2004 to 2016 (a period of 12 years): (1) forest cover and open area significantly decreased at rates of almost 30 and 8 km2, respectively; (2) cultivated land and oil palm have shown an increment in sizes at rates of 25.02 and 5.77 km2, respectively; and, (3) settlement and Urbanization has intensified also by almost 5 km2. Soil erosion risk analysis results also showed that the Semenyih basin exhibited an average annual soil erosion between 143.35 ton ha?1 year?1 in 2004 and 151 in 2010, followed by the expected 162.24 ton ha?1 year?1. These results indicated that Semenyih is prone to water erosion by 2016. The wide range of erosion classes were estimated at a very low level (0–1 t/ha/year) and mainly located on steep lands and forest areas. This study has shown that using both LTM and USLE in combination with remote sensing and GIS is a suitable method for forecasting LC and accurately measuring the amount of soil losses in the future. 相似文献
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This study was undertaken to prepare an inventory on soil erosion of a hilly river watershed — the Aglar watershed, part of Tehri Garhwal and Dehradun districts (U.P.), using terrain physiography and soil survey data obtained from interpretation and analysis of Landsat TM FCC (1:62,500 scale) and limited ground investigations. The watershed is divided into four broad physiographic units viz. higher Himalayas (> 2000m elevation); lower Himalayas (< 2000m elevation); river terraces and flood plains. Each physiographic unit has been further divided into subunits on the basis of aspects and landuse. Three major orders of soils viz. Inceptisols, Mollisols and Entisols were found in different physiographic units. Soil, and land properties of soilscape units viz. soil depth, texture, structure, slope, landuse and soil temperature regime were evaluated for soil-erosion hazard. The results indicate that in the whole watershed 19.13%, 45.68%, 26.51% and 7.92% areas have been found to be under none to slight, moderate, severe and very severe soil erosion hazard categories, respectively. 相似文献
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Birendra Nath Ghosh Krishnendu Das Siladitya Bandyopadhyay Subrata Mukhopadhyay Dulal Chandra Nayak Surendra Kumar Singh 《Journal of the Indian Society of Remote Sensing》2018,46(4):641-654
GIS based land resource inventory (LRI) with fine resolution imagery is considered as most authentic tool for soil resource mapping. Soil resource mapping using the concept of soil series in a smaller scale limits its wide application and also its impact assessment for crop suitability is controversial. In this study, we attempted to develop LRI at large scale (1:10,000 scale) at block level land use planning (LUP) in Dandakaranya and Easternghats physiographic confluence of India. The concept of land management unit was introduced in this endeavour. The impact assessment of LRI based LUP was exercised to develop efficient crop planning with best possible management practices. The study area comprised six landforms with slope gradient ranging from very gentle (1–3%) to steep slopes (15–25%). The very gently sloping young alluvial plains occupied maximum areas (19.95% of TGA). The single cropped (paddy) land appears to dominate the land use systems (40.0% of TGA). Thirty three landscape ecological units were resulted by GIS-overlay. Eighteen soils mapping units were generated. The area was broadly under two soil orders (Inceptisols and Alfisols); three great group (Haplaquepts, Rhodustalfs and Endoaquepts) and ten soil series. Crop suitability based impact assessment of LRI based LUP revealed that average yield of different crops increased by 39.2 and 14.5% in Kharif (rainy season) and Rabi (winter) seasons respectively and annual net returns by 83.4% for the cropping system, compared to traditional practices. Productivity and net returns can be increased several folds if customized recommended practices are adopted by the farmers. Informations generated from the study emphasized the potentiality of LRI towards optimizing LUP and exhibited an ample scope to use the methodology as a tool to assess in other physiographic regions in India and abroad. 相似文献
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M. S. S. Nagaraju G. P. Obi Reddy A. K. Maji Rajeev Srivastava P. Raja A. K. Barthwal 《Journal of the Indian Society of Remote Sensing》2011,39(1):51-61
The study area is characterized by low and fluctuating rainfall pattern, thin soil cover, predominantly rain-fed farming with low productivity coupled with intensive mining activities, urbanization, deforestation, wastelands and unwise utilization of natural resources causing human induced environmental degradation and ecological imbalances, that warrant sustainable development and optimum management of land resources. Spatial information related to existing geology, land use/land cover, physiography, slope and soils has been derived through remote sensing, collateral data and field survey and used as inputs in a widely used erosion model (Universal Soil Loss Equation) in India to compute soil loss (t/ha/yr) in GIS. The study area has been delineated into very slight (<5 t/ha/yr), slight (5–10 t/ha/yr), moderate (10–15 t/ha/yr), moderately severe (15–20 t/ha/yr), severe (20–40 t/ha/yr) and very severe (>40 t/ha/yr) soil erosion classes. The study indicate that 45.4 thousand ha. (13.7% of TGA) is under moderate, moderately severe, severe and very severe soil erosion categories. The physiographic unit wise analysis of soil loss in different landscapes have indicated the sensitive areas, that has helped to prioritize development and management plans for soil and water conservation measures and suitable interventions like afforestation, agro-forestry, agri-horticulture, silvipasture systems which will result in the improvement of productivity of these lands, protect the environment from further degradation and for the ecological sustenance. 相似文献
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Anton Vrieling Steven M. de Jong Geert Sterk Silvio C. Rodrigues 《International Journal of Applied Earth Observation and Geoinformation》2008
Erosion reduces soil productivity and causes negative downstream impacts. Erosion processes occur on areas with erodible soils and sloping terrain when high-intensity rainfall coincides with limited vegetation cover. Timing of erosion events has implications on the selection of satellite imagery, used to describe spatial patterns of protective vegetation cover. This study proposes a method for erosion risk mapping with multi-temporal and multi-resolution satellite data. The specific objectives of the study are: (1) to determine when during the year erosion risk is highest using coarse-resolution data, and (2) to assess the optimal timing of available medium-resolution images to spatially represent vegetation cover during the high erosion risk period. Analyses were performed for a 100-km2 pasture area in the Brazilian Cerrados. The first objective was studied by qualitatively comparing three-hourly TRMM rainfall estimates with MODIS NDVI time series for one full year (August 2002–August 2003). November and December were identified as the months with highest erosion risk. The second objective was examined with a time series of six available ASTER images acquired in the same year. Persistent cloud cover limited image acquisition during high erosion risk periods. For each ASTER image the NDVI was calculated and classified into five equally sized classes. Low NDVI was related to high erosion risk and vice versa. A DEM was used to set approximately flat zones to very low erosion risk. The six resulting risk maps were compared with erosion features, visually interpreted from a fine-resolution QuickBird image. Results from the October ASTER image gave highest accuracy (84%), showing that erosion risk mapping in the Brazilian Cerrados can best be performed with images acquired shortly before the first erosion events. The presented approach that uses coarse-resolution temporal data for determining erosion periods and medium-resolution data for effective erosion risk mapping is fast and straightforward. It shows good potential for successful application in other areas with high spatial and temporal variability of vegetation cover. 相似文献
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M. L. Manchanda Jitendra Prasad H. S. Iyer S. K. Deb R. Pathak 《Journal of the Indian Society of Remote Sensing》1984,12(1):7-18
Soil and Soil Conservation surveys for watershed management were conducted using aerial photos of 1:60,000 scale in parts of North Cachar and Karbi-Anglong districts of Assam. The area was divided into different river catchments and sub-watersheds. The erosion, slope, landuse and soils in relation to physiogrphy were studied in each sub-watershed. The different physiographic units identified in the area were high, medium, low and very low hills; pediplains; alluvial plain and the valleys. These units were further subdivided based on slope, landuse and erosion etc. The soils were classified according to Soil Taxonomy. For priority determination, weightage was alloted to each of the sub-watersheds considering their physiography, slope, landuse, erosion,soil texture, depth and delivery ratio and sediment yield was calculated for each subwatershed. It has been found that out of 122875 ha, an area of 1745 ha had very high priority, 30590 ha high, 37290 ha medium, 51957 ha low and 1294 ha very low priority for soil conservation purposes. 相似文献
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V. C. Patil B. T. Nadagouda K. A. Al-Gaadi 《Journal of the Indian Society of Remote Sensing》2013,41(1):183-189
Investigations were carried out to develop precision nutrient management techniques for sugarcane. The study area (800 ha) comprised of Bijapur, Bilgi and Jamakhandi talukas that lie between 16° 34′–28° 10′ N latitudes and 75° 33′–75° 37′ E longitudes and located around Nandi Sahakari Sakkare Karkhane (NSSK) Niyamit, Galagali. The soils are medium to deep black with pH and EC ranging from 7.32 to 8.36 and 0.17 to 1.13 dS/m, respectively. The soils are low to medium in available nitrogen, medium in available phosphorus and high in available potassium content. Crop condition assessment was made through analysis of LISS-III satellite images using Erdas Imagine software. Fertigation with 300 kg N and 195 kg K per ha at fortnightly interval and soil application of 32 kg P per ha as basal, recorded higher sugarcane yield (167 Mg ha?1) as compared to 124 Mg ha?1 obtained with soil application of 250 kg N, 32 kg P and 156 kg K per ha and flood irrigation as per the package recommended by the University(POP). Fertigation of N and K at weekly interval recorded highest NDVI value (0.354) and soil application of nutrients as per POP resulted in the lowest NDVI of 0.219. 相似文献