Estimation and mapping of water erosion and soil loss:Application of Gavrilovic erosion potential model(EPM)using GIS and remote sensing in the Assif el mal Watershed,Western high Atlas

Water erosion is a serious problem that leads to soil degradation,loss,and the destruction of structures.Assessing the risk of erosion and determining the affected areas has become crucial in order to understand the main factors influencing its evolution and to minimize its impacts.This study focuses on evaluating the risk of erosion in the Assif el mal watershed,which is located in the High Atlas Mountains.The Erosion Potential Model(EPM)is used to estimate soil losses depending on various parameters such as lithology,hydrology,topography,and morphometry.Geographic information systems and remote sensing techniques are employed to map areas with high erosive potential and their relationship with the distribution of factors involved.Different digital elevation models are also used in this study to highlight the impact of data quality on the accuracy of the results.The findings reveal that approximately 59%of the total area in the Assif el mal basin has low to very low potential for soil losses,while 22%is moderately affected and 19.9%is at high to very high risk.It is therefore crucial to implement soil conservation measures to mitigate and prevent erosion risks.

Visual Analysis of Remote Sensing Monitoring of Soil Salinization

Soil salinization seriously restricts the development of agricultural production,the sustainable use of land resources,and the stability of the ecological environment.In order to objectively reveal the research status of soil salinization,CiteSpace software was used to conduct data mining and quantitative analysis on research papers on soil salinization from 2008 to 2023 in China National Knowledge Infrastructure(CNKI)and Web of science databases.The data sources were transformed into visual graphs by reproducing clustering statistics from aspects such as publication volume,authors,keywords,and publishing institutions.In addition,this paper also combined the actual needs and cutting-edge hotspots in relevant research in China,and proposed and analyzed the limitations and future development trends of soil salinity monitoring research in China.This has important practical significance for comprehensively grasping the current research status of salinization,further clarifying and sorting out the research ideas of salinization monitoring,enriching the remote sensing monitoring methods of saline soil,and solving the actual problems of soil salinization in China.

Application of Remote Sensing in Study of Slope Land Use and Soil Erosion in Subtropic Region of China

This paper introduces briefly two remote sensing case studies on land use in the subtropic region of China. One is on slope land use in the Yangtze River Three Gorges area. This is a large area of 60497 km2.First of all, geometric correction and supervised classification were conducted for ten scenes of Landsat-5 TM or MSS images. The resolution of the processed images is 50 m ×50 m on ground. By the classification the land use/cover categories in this area were discriminated. Then the croplands including rice fields and upland fields were extracted from the land use/cover maps. Simultaneously the slope grade maps were prepared based on the topographic maps. Overlaying the slope grade maps and the cropland maps, the area and percentage of the croplands in different slope grades were determined. This case study indicated that 71.5% of the uplands was situated on the slope above 15° and 25% on the slope above 25° in this area. It is dangerous, and urgent cultivation or engineering measures should be taken. Another case study is on soil erosion in Linshan County of Guangxi Province. Airphoto interpretation and supervised classification of a Landsat TM image were carried out for discriminating land cover/use categories in an area of 3557.8 km2.And the soil erosion intensity grades were determined according to the land cover/use maps and slope maps.It wed discovered that the land suffering soil erosion accounted for 2404.0 km2, 67.6% of the total area of the county. Necessary measures to control soil erosion should be taken also.

Dynamics of Soil Erosion in Xingguo County, China, Determined Using Remote Sensing and GIS

The spatial and temporal dynamics of soil erosion in Xingguo County, Jiangxi Province, China were studied using multi-period remote sensing images and GIS. The results indicated that the soil erosion status of the region has been improving, particularly since the 1980s, with the erosion rate showing an evident decline over the past 30 years. The improvement showed not only in the decline of eroded soil area, but also with the reduction in the extent of erosion. The extent of erosion mainly changed by one level, and the change primarily occurred with the severely or moderately eroded soil types. However, in general, soil erosion was still an overriding problem in the region with some areas becoming more serious, especially those with large quantities of granite.

Assessment of soil erosion by RUSLE model using remote sensing and GIS-A case study of Nethravathi Basin

Soil erosion is a serious problem arising from agricultural intensification, land degradation and other anthropogenic activities. Assessment of soil erosion is useful in planning and conservation works in a watershed or basin. Modelling can provide a quantitative and consistent approach to estimate soil erosion and sediment yield under a wide range of conditions. In the present study, the soil loss model, Revised Universal Soil Loss Equation （RUSLE） integrated with GIS has been used to estimate soil loss in the Nethravathi Basin located in the southwestern part of India. The Nethravathi Basin is a tropical coastal humid area having a drainage area of 3128 km2 up to the gauging station. The parameters of RUSLE model were estimated using remote sensing data and the erosion probability zones were determined using GIS. The estimated rainfall erosivity, soil erodibility, topographic and crop management factors range from 2948.16 to 4711.4 MJ/mm.ha-1hr-1/year, 0.10 to 0.44 t ha-1 -MJ-1.mm 1, 0 to 92,774 and 0 to 0.63 respectively. The results indicate that the estimated total annual potential soil loss of about 473,339 t/yr is comparable with the measured sediment of 441,870 t/yr during the water year 2002 2003. The predicted soil erosion rate due to increase in agricultural area is about 14,673.5 t/yr. The probability zone map has been derived by the weighted overlay index method indicate that the major portion of the study area comes under low probability zone and only a small portion comes under high and very high probability zone. The results can certainly aid in implementation of soil management and conservation practices to reduce the soil erosion in the Nethravathi Basin.

Soil erosion in China based on the 2000 national remote sensing survey

This paper discussed the spatial distribution of soil erosion in China at the end of the 20th century based on the second national soil erosion survey. The result indicated soil erosion is still the prime environmental problem in China. Soil erosion mainly occurs in the western regions of China, and the slight erosion type, ion the whole, exerts the greatest impact on soil erosion pattern. The distribution of water erosion shows the impact of landforms: slight water erosion mainly in mountainous and hilly areas, and half of violent water erosion on the loess landforms. Farmland, forestland and grassland are the major land use types of slight hydraulic erosion distribution, while the serious hydraulic erosion and slight wind erosion mainly occur on grassland. Thus, the conservation of the grassland is the key to either hydraulic and wind erosion control. The huangmian soil (a major type of cultivated soil developed from loess mother material) is the one facing the most serious threat from soil erosion in Chinas soil resources. Further discussion on the soil erosion distribution still needs more research on the method and relevant data analysis.

A New Software for GIS Image Pixel Topographic Fac－tors in Remote Sensing Monitoring of Soil Losses

Based on the new algorithm for GIS image pixel topographic factors in remote sensing monitoring ofsoil losses, a software was developed for microcomputer to carry out computation at a medium river basin(county). This paper lays its emphasis on algorithmic skills and programming techniques as well as applicationof the software.

Remote-sensing data reveals the response of soil erosion intensity to land use change in Loess Plateau, China

Developing an effective approach to rapidly assess the effects of restoration projects on soil erosion intensity and theirextensive spatial and temporal dynamics is important for regional ecosystem management and the development of soilconservation strategies in the future. This study applied a model that was developed at the pixel scale using water soilerosion indicators （land use, vegetation coverage and slope） to assess the soil erosion intensity in the Loess Plateau,China. Landsat TM/ETM＋ images in 2000, 2005 and 2010 were used to produce land use maps based on the object-oriented classification method. The MODIS product MOD13Q1 was adopted to derive the vegetation coveragemaps. The slope gradient maps were calculated based on data from the digital elevation model. The area of watersoil-eroded land was classified into six grades by integrating slope gradients, land use and vegetation coverage. Resultsshow that the Grain-To-Green Project in the Loess Plateau worked based on the land use changes from 2000 to 2010and enhanced vegetation restoration and ecological conservation. These projects effectively prevented soil erosion.During this period, lands with moderate, severe, more severe and extremely severe soil erosion intensities significantlydecreased and changed into less severe levels, respectively. Lands with slight and light soil erosion intensities increased.However, the total soil-eroded area in the Loess Plateau was reduced. The contributions of the seven provincesto the total soil-eroded area in the Loess Plateau and the composition of the soil erosion intensity level in eachprovince are different. Lands with severe, more severe and extremely severe soil erosion intensities are mainly distributedin Qinghai, Ningxia, Gansu and Inner Mongolia. These areas, although relatively small, must be prioritised andpreferentially treated.

Study on soil erosion dynamics in typical regionof southern China based on remote sensing, GISand gray forecast model

This paper StUdies soil erosion dynamics in the typical region of southem China based onremote sensing, GIS tecndques and gray forecast model. The resultS of survey on Xingguo countyshown the soil eroded area and annual soil erosion amount decreased by 19.09% and 43.05%reSPectively from 1958 to 1988. The results of gray forecast model presented that soil eroded areaincreased from 818.04 km2 in 1988 to 1276.69 km2 in 1995. in the meanthne the total soil erosiollamount decreased from 607.21×104 ba in 1988 to 472. 12 ×104 t/a in 1995. By comparing differentlanduse types, the soil loss modulus of the forest was the lowest with 177. 16~187.75t/km2. a, on thecontraly the bare land was the highest with 10626.76~11265.48 t/km2. a. so the high vegetationcoverage can decrease soil and water loss effectively.

Using remote-sensing technologies in combination with Cesium-137 measurements to estimate soil-erosion quantity in semi-arid steppe areas

Soil erosion by wind is one of the most important processes in the changing the earth's surface in semi-arid areas,Thus it is of great importance to study soil-erosion action.Using integrated technologies of remote sensing and geochemistry radioactivity iso-tope to extract regional soil-erosion information and to calculate quantity of soil erosion is accomplished successfully in this paper by means of beneficial experiments in the Talatan region of the Gonghe Basin,which is located in northeastern Qinghai-Tibet Pla-teau in China.The results show that the soil erosion by wind is not intensive in this region;the erosion types belong to the classes of very-soft erosion and soft-erosion type,which account for 47.12 percent and 35.58 percent,respectively,of the total study area.In total,two kinds of soil erosion account for 82.70 percent of the study area;only a small area belongs to the classes of severe erosion and very-severe erosion;this area is about 22.14 km2.Severe deposition activity has taken place in this region,and has appeared in a large area(322.67 km2),which accounts for 11.78 percent of the total study area.The results of this study show that soil erosion and deposition inventories are 870,000-1,150,000 tons and 550,000-780,000 tons,respectively,per year.The soil in-ventory shows about 320,000-370,000 tons from Talatan to Longyangxia reservoir per year.Using remote-sensing technology and 137Cs techniques is a valid means to analyze and to evaluate the quantity of soil erosion by wind in semi-arid environments.

Research on the Optimal Vegetation Cover for Remote Sensing Assessment of Soil Erosion Risk Using the Temporal Matching Relationship between Rainfall and Vegetation

Vegetation cover derived from remote sensing image is widely used for soil erosion risk assessment, but there is no clear guideline to select the most appropriate temporal satellite data. It is common practice that satellite data during growing season are randomly selected and used in soil erosion risk assessment. However, the effectiveness of vegetation in protecting the soil is quite different even if it is the same growing season since vegetation covers change as they grow. This article aims to provide a method of choosing optimal vegetation cover for studying soil erosion risk using remote sensing, that is, the vegetation cover in the most appropriate temporal period. Based on the temporal relationship of the two most active impact factors, rainfall and vegetation, an index of RV is developed and used to indicate the relative erosion risk during the year. The results show that annual variation of rainfall is significant, and vegetation is relatively stable, resulting in their matching relationship is different in each year. The correlation coefficient reaches 0.89 between RV and real sediment transport during the period when rainfall can cause soil erosion. In other words, RV is a good indicator of soil erosion. Therefore, there is a good correlation between RV maximum and the optimal vegetation cover, which can help facilitate erosion research in the future, showing good potential for successful application in other places.

Applications of Satellite Remote Sensing Technology in China's Environmental Monitoring

The environmental conditions in China are still very serious. In the years to come, the mission for environmental treatment and protection, supervision,

Remote Sensing Dynamic Monitoring System for Agricultural Disaster in Henan Province Based on Multi-source Satellite Data

Using 3S technology, relying on earth-space three-dimensional agriculture disaster monitoring network, remote sensing monitoring model for agricultural disaster in Henan Province was established, and agricultural disaster monitoring system plat- form of Henan Province based on multi-souroe satellite data was further constructed, which realizes dynamic monitoring of agricultural disasters in Henan Province （drought, flood, snow cover and straw burning）.

Remote Sensing Monitoring of Gullies on a Regional Scale: A Case Study of Kebai Region in Heilongjiang Province, China

Gully erosion is one of the major causes of land degradation in most areas and attracts increasing attention from researchers. We monitored gullies in the Kebai region in Heilongjiang Province of China by using remote sensing data and found that gully density increased with the increase in slope when the slope was less than 3°. Gully density in sunny slopes or windward slopes was greater than in shady slopes or leeward slopes because of the impacts of freezing and thawing, wind and solar radiation. Specifically, the gully density in northeast slope was the greatest and in southwest was the smallest. Gully density was reduced with increasing slope length and the longer the slope length, the less the gully density changed between 1965 and 2005. Affected by runoff, gullies most easily to occur in concave slopes and the critical elevation for gully erosion was 250–275 m. Moreover, hilly regions had the greatest gully density, followed by tableland regions, whereas the gully density in flatlands was the lowest. However, the gully density of these three types of landforms all increased between 1945 and 2000, and the portion of increase was 57.45%(hill), 52.91%(mesa) and 25.32%(plain), respectively.

Remote Sensing Applications: Beyond Land-Use and Land-Cover Change

Remotely sensed (RS) imagery is increasingly being adopted in investigations and applications outside of traditional land-use land-cover change (LUCC) studies. This is due to the increased awareness by governments, NGOs and Industry that earth observation data provide important and useful spatial and temporal information that can be used to make better decisions, design policies and address problems that range in scale from local to global. Additionally, citizens are increasingly adopting spatial analysis into their work as they utilize a suite of readily available geospatial tools. This paper examines some of the ways remotely sensed images and derived maps are being extended beyond LUCC to areas such as fire modeling, coastal and marine applications, infrastructure and urbanization, archeology, and to ecological, or infrastructure footprint analysis. Given the interdisciplinary approach of such work, this paper organizes selected studies into broad categories identified above. Findings demonstrate that RS data and technologies are being widely used in many fields, ranging from fishing to war fighting. As technology improves, costs go down, quality increases and data become increasingly available, greater numbers of organizations and local citizens will be using RS in important everyday applications.

Studying the Condition of Soil Protection Agrolandscape in Ukraine Using Remote Sensing Methods

The article reviews the scientific approaches to monitoring of soil condition on the soil protection agrolandscape. In 1980s, the contour-meliorative soil protection system was established on the selected fields in Ukraine. The objective of the current research was to determine the capabilities of satellite survey to identify the changes of soil cover that had occurred on these fields during the past 25 years. Soil erosion processes are very dynamic, therefore it is essential to use time-series of operative satellite images to track those changes. Rills on the fields, caused by water erosion, are clearly identified on high-resolution satellite data. Erosion causes the decrease of humus content, which affects soil reflection values. This in turn leads to a corresponding change of color shade on satellite images. The research allowed to determine correlation between remote sensing data and soil organic carbon content and to acquire a mathematical model which describes this correlation. The condition of the agrolandscape soils was assessed using the regression model, which helped to evaluate erosion risk for different areas of the test polygon. The visual interpretation of satellite imagery led to a conclusion about a damaging effect of erosion on protective forest belts and accordingly on fields＇ soil cover and crops. Visual analysis results were approved by field research. Photos taken during the field research indicate an unsatisfactory status of forest belts and a devastating effect of eroding water flows. These are the results of irresponsible land use and constant violation of methodical principles of the contour-meliorative system organization. The article concludes that the use of time-series of high-resolution satellite imagery allows monitoring the condition of soil protection agrolandscape, in particular the forest belts＇ status soil cover conditions and their change over time. The research results can be used as an informational basis for the soil protection agrolandscape monitoring system.

A STUDY OF SOIL CONSERVATION MONITORING INFORMATION SYSTEM BASED ON REMOTELY SENSED DATA FOR A CATCHMENT ON THE LOESS PLATEAU

The Soil Conservation Monitorins Information System (SCMIS) presented in this paper is oriented to soil erosion control, resources exploitation, utilization, planning and management for a small watershed (about 10 sq. km.) on the Loess Plateau. It sums up Remote sensing (RS), Geographical Information System (GIS) and Expert System (ES) and consists of a integrated system. As a basic level information system of Loess Plateau, its perfection and psreading will bring about a great advance in resources exploitation and management of Loess Plateau.

Environmental Factors Affecting Temporal and Spatial Dynamics of Soil Erosion in Xingguo County, South China

By using soil erosion maps of four different time periods and a digital elevation model (DEM), in combination withthe remote sensing and GIS technologies, soil erosion dynamics in Xingguo County of Jiangxi Province in South Chinawere analyzed on both temporal and spatial scales in soils of different parent materials, altitudes and slopes. The resultsshowed that from 1958 to 2000 severe soil erosion was coming under control with a decreasing percentage of the land undersevere erosion. It was also found that the soils developed from Quaternary red clay, granite and purple shale were moresusceptible to soil erosion and that areas sitting between 200 to 500 m in altitude with a slope less than 3° or between7° to 20° where human activities were frequent remained to be zones where soil erosion was most likely to occur. Theseareas deserve special attention in monitoring and controlling.

An Integrated GIS/RS Approach for Soil Erosion Assessment and Modeling in Syrian Coastal Soils

An integrated remote sensing (RS) and geographic information system (GIS) technique was employed to characterize the spatial distribution of the risk of soil erosion by water on Latakia district, Syria. The universal soil loss equation (USLE) was used to calculate the annual soil loss rates for Latakia soils. Mainly, remote sensing data, soil survey, land use inventory, elevation data and climatic atlases are used as resource data sets to generate USLE factor values. The results revealed that integration of GIS/RS with USLE was a practical and effective approach for monitoring soil erosion over large areas.

Temporal and Spatial Conversion Analysis of Soil Erosion in the Three Gorges Region Based on RS and GIS Technique——A Case Study in Kaixian County

In this paper, Kaixian County, situated in the hinterland of the Three Gorges Reservoir Region, was selected for the case study. Factors of soil erosion were obtained based on the technique of remote sensing （RS） and geographic information system （GIS）. Combining with field survey, soil erosion data in the years of 1988, 2000 and 2004 which covered the period from the beginning of the Three Gorges Reservoir Project to nowadays were investigated through the judgment model established on soil erosion intensity. With the function of spatial analysis in the geographic information system, the analysis and appraisal of dynamic soil erosion changes were carried out, and the spatial characteristics of the vicious change were highlighted, and the main causes of the vicious change of soil erosion were explored.