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Jilong Li Jiaming Na Xue Yang Jianjun Cao Wen Dai Guoan Tang 《Transactions in GIS》2019,23(1):137-157
The loess shoulder‐lines are known to be the most critical topographic structural lines in the loess landform area of the Loess Plateau, China. Previous studies have shown that gully erosion activity can be reflected in the dynamic changes of the shoulder‐lines. In this study, active gully erosion sites along the shoulder‐lines are investigated. Three typical test areas with different loess landforms are selected, and the loess shoulder‐lines are derived from 1 m resolution digital elevation models. First, height profiles of the loess shoulder‐lines are extracted. Then, from the perspective of frequency domains, active gully erosion sites are identified using the Hilbert–Huang transform (HHT). The experimental results show that the HHT method can effectively mine the intrinsic characteristics of the shoulder‐lines. The detailed information components (non‐components) and trend components of the height profiles can be obtained via ensemble empirical mode decomposition and a significance test. In addition, the HHT method was employed to identify the instantaneous frequency curve catastrophe points of the loess shoulder‐line height profiles, and the physical meaning is clear: a higher frequency denotes greater energy and more severe erosive processes, and the catastrophe point locations represent the active gully erosion sites. Evidence from a recent field survey and a comparison with another method supports the results, indicating that the method proposed in this study could potentially be effective for the exploration and analysis of geomorphologically sensitive locations in loess landform studies. 相似文献
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针对传统沟蚀监测手段劳作强度大,且数据采集的完整性、代表性受切沟复杂地形制约等问题,提出了一种针对植被稀疏地区沟蚀变化的地面激光扫描(terrestrial laser scanning,TLS)监测方法,形成了一套数据处理与侵蚀量计算技术流程。以河北省官厅水库东岸某大型切沟为例,利用高精度TLS进行两年3期野外监测与点云数据分析。通过点云配准、滤波、重采样及曲面拟合等预处理,生成不同采样分辨率下3期切沟表面模型,并提取地形信息;采用杨赤中滤波推估法计算并比较不同点云重采样分辨率下的沟蚀量。结果表明:(1)当点云重采样分辨率与切沟表面凹凸微结构暨石块粒径(2~6cm)接近时,沟蚀量估算值趋于稳定、结果可靠;(2)经侵蚀作用,切沟外壁表面高程整体降低2~20 cm;(3)切沟内壁侵蚀量不均衡,坡度较大处侵蚀最为显著。 相似文献
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Hassan M. Fadul Ahmed A. Salih Imad-eldin A. Ali Shinobu Inanaga 《International Journal of Applied Earth Observation and Geoinformation》1999,1(3-4)
The problems and impact of gully erosion along the Atbara River (Sudan), situated in semi-arid and arid environments, were investigated. The total gross area of gullied land and the loss of arable land by gully erosion were estimated. Multi-date sets of panchromatic aerial photographs and Landsat images (TM) were selected to represent two sites in the arid (New Halfa) and semi-arid (Showak town) zones along the Atbara River. Photo interpretation was conducted using physiographic and element methods. The interpretations detected the effects of water action in different climatic zones on geology, lithology, vegetation and land use. The results showed that the traditional rainfed agriculture has accelerated gully erosion in the semi-arid rather than in the arid zone. The progressive rate of gully erosion in the semi-arid zone resulted in loss of arable land at about 13.4 km2 yr-1 and 9.8 km2 yr-1 in the periods 1985–1987 and 1987–1990, respectively. The study provided data on the monitoring and mapping of gully erosion along the Atbara River and its tributaries. 相似文献
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东北黑土区侵蚀沟遥感影像特征提取与识别 总被引:3,自引:0,他引:3
东北黑土区是中国重要的粮食生产区,而长期的开垦造成了严重的水土流失现象,坡耕地表面出现大量的侵蚀沟。侵蚀沟的识别是土壤侵蚀监测的重要手段之一,目前遥感技术在侵蚀沟的识别中应用广泛,但自动化程度不高。针对特定地物影像的识别,如何选取最能够有效描述该地物的特征是解决问题的关键。本文构建了耕地和侵蚀沟遥感影像的训练样本集,基于样本集分别提取了由光谱特征和纹理特征组成的浅层特征、SIFT特征经编码后得到的中层特征,以及利用卷积神经网络提取的深层特征;再基于不同层次的特征选用合适的分类器对遥感影像进行分类,识别出含有侵蚀沟的遥感影像,形成了一套针对侵蚀沟的特征提取与识别方法,为东北黑土区的耕地保护提供有力支持。测试结果表明:基于中层特征的识别精度最高,为98.5%,但该特征需要人工设计,自动化程度有限;而利用卷积神经网络可自动提取深层特征,其识别精度达到了95.5%,同时大大提高了自动化程度,满足侵蚀沟影像的识别的需求。 相似文献
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在地形破碎的黄土丘陵地区,利用航空遥感图像分析沟谷密度、沟谷发育阶段、地貌形态及其与土壤侵蚀强度之间的相关性,收到了良好的效果。研究表明,包括切沟在内的黄土丘陵区的沟谷密度值可高达20 km/km~2以上;黄土冲沟的发育阶段不同,其侵蚀强度也相应变化;切沟发育最活跃和最密集的地段,其侵蚀强度也最大。根据土壤侵蚀总量与侵蚀强度之间的相关,建立了土壤侵蚀模型,并利用遥感图像划分了土壤侵蚀综合类型,从而可用多元回归分析方法求算各侵蚀类型的侵蚀强度,为预测区域侵蚀总量开辟了新的技术途径。 相似文献
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Gully boundary extraction based on multidirectional hill‐shading from high‐resolution DEMs 下载免费PDF全文
The gully boundary, which distinguishes gully from non‐gully areas, is a significant geomorphologic feature for research on gully development and gully erosion. This study presents a new method based on multidirectional hill‐shading maps, which identify the gully (i.e., shadow area) from inter‐gully (i.e., non‐shadow area). These shadows obtained from various illumination azimuths are merged; consequently, the border of the shadows, which is the gully boundary line, can be achieved. In this process, two key parameters, namely, altitude and azimuth of light, affect the accuracy of gully boundary extraction. The experiments in Yaojiawan area of China show that the method of average median slope of all sampling profiles across the gully boundary is effective and practical for light altitude selection. Moreover, the six azimuths are sufficient for gully boundary extraction in a loess hilly area. The application in the Madigou area indicates the replicability and rationality of this method. A comparison with the positive‐negative terrain and slope variation method confirms a higher accuracy of gully boundary extraction by the proposed method in terms of visual interpretation, length, and contour‐matching difference with reference to manually digitalized results. Accuracy assessment indicates that the proposed method is applicable for gully boundary extraction based on high‐resolution DEMs. 相似文献
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本研究工作是在利用航空遥感信息进行黄土丘陵沟壑区侵蚀环境系列制图的基础上,对黄土侵蚀环境动态变化作了初步分析探讨。通过利用山西省离石县王家沟流域不同时期的航空像片,应用先进的地理信息系统软件ARc/INFO系统编制出了该流域不同时期,不同时段和不同类型的侵蚀环境系列图,包括影响侵蚀因素系列图、土壤侵蚀量分布图,流域沟谷形态变化图,时段侵蚀平均发展速度图以及治理评价图,并在此基础上,利用环境动态分析法分时段分析了流域侵蚀状况变化及其环境的变化。在侵蚀环境的分析中·不仅分析了影响侵蚀的自然因素,还揭示了人为因素对侵蚀的影响。研究结果,为黄土高原小流域水土流失综合治理措施的制定提供了科学依据。 相似文献
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Remote gully erosion mapping using aster data and geomorphologic analysis in the Main Ethiopian Rift
The Main Ethiopian Rift (MER) is an area of extreme topography underlain by post-Miocene volcanic rocks, Jurassic limestone and a Precambrian basement. A prime concern is the rapid expansion of wide gullies that are impinging on agricultural land. We investigate the potential contribution of Advanced Space-borne Thermal Emission and Reflection Radiometer (ASTER) data and geomorphologic parameters to discern patterns and features of gully erosion in the MER. Maximum Likelihood Classification (MLC), Support Vector Machine (SVM), and Minimum Distance (MD) classifiers are used to extract different gully shapes and patterns. Several spatial textures based on Grey Level Co-occurrence Matrices (GLCMs) are then generated. Afterwards, the same classifiers are applied to the ASTER data combined with the spatial texture information. We used geomorphologic parameters extracted from SRTM and ASTER DEMs to describe the geomorphologic setting and the gullies’ shapes. The classifications show accuracies varying between 67% and 89%. Maps derived from this quantitative analysis allow the monitoring and mapping of land degradation as a direct result of gully-widening. This study reveals the utility of combining ASTER data and spatial textural information in discerning areas affected by gully erosion. 相似文献
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Remote gully erosion mapping using aster data and geomorphologic analysis in the Main Ethiopian Rift 总被引:1,自引:0,他引:1
The Main Ethiopian Rift(MER)is an area of extreme topography underlain by post-Miocene volcanic rocks,Jurassic limestone and a Precambrian basement.A prime concern is the rapid expansion of wide gullies that are impinging on agricultural land.We investigate the potential contribution of Advanced Space-borne Thermal Emission and Reflection Radiometer(ASTER)data and geomorphologic parameters to discern patterns and features of gully erosion in the MER.Maximum Likelihood Classifica-tion(MLC),Support Vector Machine(SVM),and Minimum Distance(MD)classifiers are used to extract different gully shapes and patterns.Several spatial textures based on Grey Level Co-occurrence Matrices(GLCMs)are then generated.Afterwards,the same classifiers are applied to the ASTER data combined with the spatial texture information.We used geomorphologic parameters ex-tracted from SRTM and ASTER DEMs to describe the geomorphologic setting and the gullies’ shapes.The classifications show accuracies varying between 67% and 89%.Maps derived from this quantitative analysis allow the monitoring and mapping of land degradation as a direct result of gully-widening.This study reveals the utility of combining ASTER data and spatial textural infor-mation in discerning areas affected by gully erosion. 相似文献
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基于遥感和GIS的水土流失因子信息提取与分级定标研究--以攀枝花市为例 总被引:12,自引:0,他引:12
以攀枝花市为例,主要选用美国陆地卫星2003年的Landsat-7 ETM+遥感数据、1∶10万地形图,运用ERDAS/IMAG INE遥感图像处理软件及M apG IS软件提取对水土流失影响较大的植被覆盖度、地形坡度、沟谷密度、土地利用类型等因子;根据中华人民共和国行业标准《土壤侵蚀分类分级标准》(SL 190-96),建立攀枝花市水土流失强度面蚀分级指标,为进一步水土流失监测研究提供科学依据。 相似文献
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介绍了新一代图像处理系统ER Mapper及其应用,分析了不同空间尺度下影响水土流失的地形因子,针对ER Mapper的图像处理功能,对地形因子的提取技术进行了初步探讨,并取得了一定的成果。 相似文献
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在水电站建设工程中,需要对水土保持进行监测,本文提出了一种新的侵蚀沟监测方案,实践证明它比传统的监测结果更准确,更真实,可以很直观地反映出侵蚀沟的形态,实现3维建模。同时,在安全方面真正实现了非接触式测量,大大减少了外业工作量,降低了外业危险性。 相似文献
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An area of about 5000 sq. km. in the upper parts of river basin of Sun Kosi falling in Nepal has been studied using medium and small scale aerial photographs of two different dates. The temporal variations in relation to mass movements that occur in the study area have been demarcated. The areas which have undergone increased erosion by slope failure and gully erosion over a period of 22 years are evaluated. An attempt has been made to quantify the increase in area of mass movement taking the advantage of three dimensional model of terrain as seen in the aerial photos. 相似文献
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An assessment of gully erosion along major armoured roads in south-eastern region of South Africa: a remote sensing and GIS approach 总被引:1,自引:0,他引:1
Khoboso Elizabeth Seutloali Heinz Reinhard Beckedahl Timothy Dube Mbulisi Sibanda 《国际地球制图》2016,31(2):225-239
An assessment of gully erosion along road drainage-release sites is critical for understanding the contribution of roads to soil loss and for informed land management practices. Considering that road-related gully erosion has traditionally been measured using field methods that are expensive, tedious and limited spatially as well as temporally, it is important to identify affordable, timely and robust methods that can be used to effectively map and estimate the volume of gullies along the road networks. In this study, gullies along major roads were identified from remotely sensed data sets and their volumes were estimated in a Geographic Information Systems environment. Also, the biophysical and climatic factors such as vegetation cover, the road contributing surface area, the gradient of the discharge hillslope and rainfall were derived from remotely sensed data sets using Geographic Information Systems techniques to find out whether they could explain the morphology of gullies that existed in this area. The results of this study indicate that hillslope gradient (R2?=?0.69, α = 0.00) and road contributing surface area (R2?=?0.63, α = 0.00) have a strong influence on the volume of gullies along the major roads in the south-eastern region of South Africa, as might have been expected. However, other factors such as vegetation cover (R2 = 0.52, α = 0.00) and rainfall (R2 = 0.41 and α = 0.58) have a moderately weaker influence on the overall volume of gullies. Overall, the findings of this study highlight the importance of using remote sensing and Geographic Information Systems technologies in investigating gully erosion occurrence along major roads where detailed field work remains a challenge. 相似文献
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R. L. Karale Y. P. Bali C. P. Singh 《Journal of the Indian Society of Remote Sensing》1976,4(1-2):29-36
Panchromatic vertical aerial photographs in the scale of 1: 15,000 were interpreted for assessment of erosion in the Bcas River Valley Project catchment, Himachal Pradesh in terms of the erosion intensity units. The erosion intensity units imply the relative quantum of sediment yield as deduced from the probable interaction of the significant parameters of erosion comprising physiography, slope, soil characteristics, Vegetation, land use and the visible erosion conditions. The procedure of photo-interpretation as also computation of sediment yield index for each of the different watersheds in the Beas RVP catchment is discussed. The survey revealed that out ofa total of 494 watersheds involving an area of 5.5 lakh ha, 132 watersheds comprising an area of 1.55 lakh ha, have silt yield index of over 1150 and need soil conservation measures on priority basis. Application of photo-interpretation has proved 2 times more efficient than the conventionai method that was followed in a piain area of Matatilla RVP catchment. In a more simpler terrain than Beas catchment and with ideal photographic scale of 1:60,000, the efficiency is expected to increase by 2-3 times than was achieved in Beas RVP catchment 相似文献