首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到17条相似文献,搜索用时 171 毫秒
1.
WEPP模型在砒砂岩地区土壤侵蚀模拟的适用性研究   总被引:4,自引:0,他引:4  
以内蒙古自治区准格尔旗西黑岱沟小流域为研究区,基于研究区2004~2009年的气象和土壤侵蚀资料,选取林地、草地和休闲地三种不同土地利用方式的坡面,研究了WEPP模型在三种坡面土壤侵蚀过程模拟中的适用性。结果表明:WEPP模型对研究区三种管理方式下的土壤侵蚀模拟中总体结果较好,模拟值与实测值的相关系数均较高,分别为0.915、0.889和0.899;WEPP模型模拟林地和草地土壤侵蚀的纳什模型效率分别为0.661和0.775,说明WEPP模型适用性较强,而模拟休闲地侵蚀量时效率为负值,可能与休闲地受人为活动影响较大,导致模型不能很好地模拟实际情况有关。  相似文献   

2.
在ARCGIS 8.3地理信息系统(GIS)支持下,实现了土壤侵蚀潜在危险的分级及其空间分析。首先,采用美国通用土壤侵蚀模型估算土壤侵蚀量,再用土壤年均侵蚀量、土层厚度和土壤容重得到土壤抗蚀年限图,按水利部标准将长春市土壤侵蚀潜在危险度分为五级,并提出了土壤侵蚀潜在危险指数的概念。借助GIS方法,通过分析不同坡度、不同坡向、不同地貌类型以及不同土地利用类型等背景条件下的土壤侵蚀潜在危险度情况,探讨了土壤侵蚀潜在危险度的空间分布特点。  相似文献   

3.
在ARCGIS 9.3地理信息系统支持下,实现了土壤侵蚀潜在危险度的分级及其空间分析。以青藏高原东北部的共和盆地塔拉滩草原为研究对象,首先采用地球化学放射性同位素-137Cs侵蚀模型估算土壤侵蚀量,再由土壤年均侵蚀量、土层厚度和土壤容重得到抗蚀年限图。参照水利部标准将土壤侵蚀潜在危险度分为5级,同时分析了不同坡度和不同土地利用类型上的土壤侵蚀潜在危险度。研究表明:共和盆地塔拉滩的土壤侵蚀潜在危险度以轻险型为主,从土壤侵蚀潜在危险指数(SEPDI)来看,属于轻度危险区域。  相似文献   

4.
《干旱区研究》2021,38(4):939-949
掌握天山北坡土壤水蚀分异的空间规律及其驱动力,对生态预警和土壤侵蚀防治具有重要意义,为天山北坡区域生态环境的综合治理提供理论依据和数据支持。以天山北坡中段山区为例,基于中国土壤流失方程(Chinese Soil Loss Equation,CSLE),采用野外调研、地理信息系统、数理统计和地理探测器等方法,定量分析2000—2018年研究区土壤水力侵蚀的时空格局特征(面积,强度和地理分布),借助地理探测器探究降雨、地形、土壤、植被对土壤水力侵蚀强度的内在驱动力。结果表明:(1)2000—2018年天山北坡中段山区土壤水力侵蚀强度主要以微度、轻度侵蚀为主,分别占总面积的32.34%~40.87%、33.36%~43.01%。近20 a的微度、轻度侵蚀的面积均呈下降趋势(-26.70 km~2·a~(-1)、-77.47 km~2·a~(-1)),而其他侵蚀强度的面积均呈上升趋势(22.10~30.96 km~2·a~(-1)),总体上土壤水力侵蚀强度处于增加趋势。(2)整体土壤侵蚀模数呈乌鲁木齐市昌吉市阜康市呼图壁县玛纳斯县沙湾县石河子市。天山北坡中段山区侵蚀强度的空间分布与降雨、地形、土壤、植被密切相关,土壤类型为棕钙土、草毡土、栗钙土,植被覆盖度小于15%、坡度大于15°和降雨量在400~450 mm范围内的地区为高风险侵蚀区域。(3)分异性的大小由因子探测器中q值来度量,其q值越大,该影响因素对土壤侵蚀空间分布的解释力越强,呈降雨(0.49)土壤类型(0.17)坡度(0.11)植被覆盖度(0.10)。不同影响因素通过交互作用明显增强土壤侵蚀空间异质性,及植被覆盖度与降雨因子的耦合作用,q值增幅极大,确定土壤侵蚀重点治理区域对全面土壤侵蚀防治具有重要意义。  相似文献   

5.
2000-2017年天山北坡西白杨沟流域土壤侵蚀时空变化分析   总被引:2,自引:0,他引:2  
掌握天山北坡西白杨沟流域水土流失时空变化特征,为该区域水土保持和生态环境建设提供科学依据。以西白杨沟流域为研究区,采用样地调查、遥感和地理信息系统相结合的方法,应用CSLE模型,定量分析2000-2017年西白杨沟流域土壤水力侵蚀时空变化特征,分析该区域侵蚀强度和坡度、旅游活动的关系,结合实地调查,探讨西白杨沟流域水力侵蚀强度变化的驱动机制。结果表明:(1)2000-2017年西白杨沟流域土壤侵蚀量总体呈增加趋势。流域内土壤侵蚀强度主要是以轻度、微度为主,分别占流域总面积的65.52%、24.71%。(2)2000-2017年西白杨沟流域不同坡度下土壤侵蚀模数变化明显。坡度≤5°时,土壤侵蚀模数无明显波动;坡度在25°~35°时土壤侵蚀模数最大,土壤侵蚀较为严重。坡度>35°时,土壤侵蚀模数减小。流域内土壤侵蚀主要发生在25°~35°。(3)植被盖度、地上生物量随着旅游强度的增加而减少(CK>LG>MG>HG),土壤侵蚀受人为活动的影响较为显著。  相似文献   

6.
基于WEPP模型进行坡度因子与侵蚀量关系研究   总被引:10,自引:1,他引:10  
地面坡度是地形因素中对坡面土壤侵蚀的演变发展过程与侵蚀强度起重要作用的因子。本文以内蒙古准格尔旗皇甫川坡面径流小区的实测资料为基础,分析坡度因子与土壤侵蚀量的关系,并运用WEPP模型进行模拟,对其结果进行分析。结果表明在一定的坡度范围内,随着坡度的增加,土壤侵蚀量与坡度呈幂函数递增关系。用WEPP模型来模拟皇甫川流域坡面与侵蚀量的关系是可行的,根据试验观测及WEPP模型模拟得到结果,皇甫川地区的土壤侵蚀率在坡度是18~23o时最大,原因主要有坡度的陡缓决定了水力阻力的大小和坡面承雨面积的改变等。  相似文献   

7.
基于GIS的藏东横断山区土壤侵蚀分布特征研究   总被引:1,自引:0,他引:1  
利用ARC/INFO的空间分析与统计分析功能,从海拔、坡度、土壤以及土地利用四个方面,对藏东横断山区土壤侵蚀的空间分布特征进行了研究。结果表明:(1)从总体上来讲,三江河谷地带水蚀较强;山体中部以微度侵蚀为主,而森林采伐迹地土壤侵蚀严重;海拔4500m以上地带,冻融侵蚀严重。(2)不同的海拔与坡度等级下,4000-5000m与25°-35°土壤侵蚀最强。(3)水力侵蚀主要发生在褐土与灰褐土土壤类型,冻融侵蚀主要发生在寒冻土、黑毡土以及草毡土土壤类型。(4)土壤侵蚀主要发生在草地和林地,低覆盖草地上冻融侵蚀尤为严重。通过土壤侵蚀分布特征的研究,为土壤侵蚀防治对策提供科学依据。  相似文献   

8.
典型黑土区坡耕地土壤侵蚀对土壤有机质和氮的影响   总被引:9,自引:0,他引:9  
基于对黑土区松花江流域东山沟小流域坡耕地耕层土壤有机质、全氮和碱解氮含量及土壤侵蚀速率的分析,研究了坡耕地土壤侵蚀强度与土壤有机质、氮素含量的相关性及坡面侵蚀、沉积对土壤有机质和氮素空间分布的影响。结果表明,土壤侵蚀强度在流域分布呈现上游>中游>下游;土壤侵蚀强度沿坡面分布呈现出较弱—强—弱的变化趋势,存在明显的侵蚀强弱交替变化规律。小流域土壤有机质和氮素含量空间分布特征与土壤侵蚀强度分布特征相对应,表现为流域上游<中游<下游;三种土壤养分沿坡长分布呈现较高—低—高的变化趋势。土壤侵蚀速率与土壤有机质、全氮含量之间呈极显著负相关关系,与碱解氮含量存在显著负相关关系,证实了土壤侵蚀是影响我国东北典型黑土区土壤质量下降最重要因素。  相似文献   

9.
以青海省乐都县、互助县6条侵蚀沟为研究对象,收集了研究区域的降雨、地形地貌、植被、土壤等数据,系统分析了各因子与土壤侵蚀量的关系。结果表明,该研究区域年侵蚀厚度与年降雨总量的变化规律不明显,土壤容重、植被覆盖度和坡度三个因子的共同作用对侵蚀量有显著的影响。区域内各影响因子对土壤侵蚀影响的大小排序为:植被盖度坡度土壤容重土壤可蚀性降雨侵蚀力,再次说明退耕还林(还草)工程能够有效改善区域水土流失问题。  相似文献   

10.
黄土地区通用土壤流失方程模型研究   总被引:3,自引:1,他引:3  
本文以晋西离石王家沟流域为试验区,介绍了黄土丘陵沟壑通用土壤流失方程(USLE)模型的构造原理和建立方法,并用灰色控制系统的理论和方法,确定了模型中各参数值,建立了适合试验区水土流失的USLE修正方程。同时用系统结构编码方法对试验区土壤可侵蚀性因子、土壤结构、土壤渗透性、作物覆盖、土壤侵蚀传递比率因子等进行了分析处理,提取了土壤侵蚀定量化因子值,从而确定了试验区流域土壤流失量的空间分布规律。  相似文献   

11.
为了给秦巴山区宁强县的水土保持与土壤侵蚀防治提供科学依据,本研究利用遥感影像解译和GIS技术,得到研究区土地利用现状、植被覆盖和数字高程模型(DEM)等数据,并利用USLE模型计算研究区的土壤侵蚀模数。结果表明,研究区的土壤侵蚀面积轻度占47.015%,中度占33.36%,强度占12.53%。土壤侵蚀严重的地区主要分布在研究区的东北部,并且也是灌溉水田、水浇地、旱地和菜地分布的区域;本研究还运用GIS和遥感技术,选用通用土壤流失方程(USLE)成功估算了宁强县的侵蚀模数及各种侵蚀等级面积,研究结果与二调结果相符合。  相似文献   

12.
The shear stress generated by the wind on the land surface is the driving force that results in the wind erosion of the soil. It is an independent factor influencing soil wind erosion. The factors related to wind erosivity, known as submodels, mainly include the weather factor(WF) in revised wind erosion equation(RWEQ), the erosion submodel(ES) in wind erosion prediction system(WEPS), as well as the drift potential(DP) in wind energy environmental assessment. However, the essential factors of WF and ES contain wind, soil characteristics and surface coverings, which therefore results in the interdependence between WF or ES and other factors(e.g., soil erodible factor) in soil erosion models. Considering that DP is a relative indicator of the wind energy environment and does not have the value of expressing wind to induce shear stress on the surface. Therefore, a new factor is needed to express accurately wind erosivity. Based on the theoretical basis that the soil loss by wind erosion(Q) is proportional to the shear stress of the wind on the soil surface, a new model of wind driving force(WDF) was established, which expresses the potential capacity of wind to drive soil mass in per unit area and a period of time. Through the calculations in the typical area, the WDF, WF and DP are compared and analyzed from the theoretical basis, construction goal, problem-solving ability and typical area application; the spatial distribution of soil wind erosion intensity was concurrently compared with the spatial distributions of the WDF, WF and DP values in the typical area. The results indicate that the WDF is better to reflect the potential capacity of wind erosivity than WF and DP, and that the WDF model is a good model with universal applicability and can be logically incorporated into the soil wind erosion models.  相似文献   

13.
半干旱黄土区沟间地浅沟分布特征   总被引:1,自引:0,他引:1  
浅沟侵蚀是半干旱黄土区坡面土壤侵蚀的重要方式。基于陕北吴起县2004年SPOT影像,提取各小流域的浅沟分布,并结合吴起县境内35个小流域土地利用调查数据,分析沟缘线以上土地利用、坡度与浅沟分布的相关性。结果表明浅沟密度依次为:丘陵区旱地〈林地〈草地;各土地利用类型的浅沟密度存在显著差异。同时,在各类土地利用类型上浅沟密...  相似文献   

14.
HE Qian 《干旱区科学》2020,12(5):865-886
Soil erosion in the Three-River Headwaters Region (TRHR) of the Qinghai-Tibet Plateau in China has a significant impact on local economic development and ecological environment. Vegetation and precipitation are considered to be the main factors for the variation in soil erosion. However, it is a big challenge to analyze the impacts of precipitation and vegetation respectively as well as their combined effects on soil erosion from the pixel scale. To assess the influences of vegetation and precipitation on the variation of soil erosion from 2005 to 2015, we employed the Revised Universal Soil Loss Equation (RUSLE) model to evaluate soil erosion in the TRHR, and then developed a method using the Logarithmic Mean Divisia Index model (LMDI) which can exponentially decompose the influencing factors, to calculate the contribution values of the vegetation cover factor (C factor) and the rainfall erosivity factor (R factor) to the variation of soil erosion from the pixel scale. In general, soil erosion in the TRHR was alleviated from 2005 to 2015, of which about 54.95% of the area where soil erosion decreased was caused by the combined effects of the C factor and the R factor, and 41.31% was caused by the change in the R factor. There were relatively few areas with increased soil erosion modulus, of which 64.10% of the area where soil erosion increased was caused by the change in the C factor, and 23.88% was caused by the combined effects of the C factor and the R factor. Therefore, the combined effects of the C factor and the R factor were regarded as the main driving force for the decrease of soil erosion, while the C factor was the dominant factor for the increase of soil erosion. The area with decreased soil erosion caused by the C factor (12.10×103 km2) was larger than the area with increased soil erosion caused by the C factor (8.30×103 km2), which indicated that vegetation had a positive effect on soil erosion. This study generally put forward a new method for quantitative assessment of the impacts of the influencing factors on soil erosion, and also provided a scientific basis for the regional control of soil erosion.  相似文献   

15.
The farming–pastoral ecotone in northern China is an extremely fragile ecological zone where wind erosion of cropland and rangeland is easy to occur. In this study, using a portable wind tunnel as a wind simulator, we conducted field simulated wind erosion experiments combined with laboratory analysis to investigate wind erosion of soils in trampled rangeland, non-tilled cropland and tilled cropland in Yanchi County, China. The results showed that compared with rangeland, the cropland had a higher soil water holding capacity and lower soil bulk density. The wind erosion rate of trampled rangeland was much higher than those of non-tilled cropland and tilled cropland. For cropland, the wind erosion rate of the soil after tilling was surprisingly less than that of the soil before tilling. With increasing of wind speed, the volume mean diameter of the eroded sediment collected by the trough in the wind tunnel generally increased while the clay and silt content decreased for all soils. The temporal variation in wind erosion of the trampled rangeland indicated that particle entrainment and dust emission decreased exponentially with erosion time through the successive wind erosion events due to the exhaustion of erodible particles.  相似文献   

16.
气候和人类活动对河北坝上丰宁县土壤风蚀沙化的影响   总被引:7,自引:1,他引:7  
人类活动强度增大和气候的变化是影响农牧交错带东南边缘农业发展的因素之一 ,本文应用灰色关联模型 ,对农牧交错带河北坝上丰宁县土壤风蚀沙化因素进行了分析 :发现影响土壤风蚀沙化的主要因素是人口增长率和冬季 1月平均气温 ,其次是耕地、草地面积的变化和夏秋 8、9月的降水量。综合来看影响该区土壤风蚀沙化的主要因素是人类活动 ,自然因素居次要地位。在人口增加和人类活动强度不断加大的情况下 ,农业生产必须依据冬季平均气温和夏秋降水量的变化来调整产业结构和生产方式 ,以减轻土壤风蚀沙化 ,实现农业的可持续发展。  相似文献   

17.
建立土地资源信息系统可以为合理开发土地资源提供信息来源与最佳方案,而数据库的设计是建立土地资源信息系统最关键部分。以乾县试区为例,应用Visual FoxPro与ARC/INFO建立基于Windows平台的黄土高原区土地资源信息系统数据库,并在此基础上设计了数据库管理系统,为建立水土流失严重、生态环境脆弱区的土地资源信息系统奠定基础。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号