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1.
Soil erosion and management on the Loess Plateau   总被引:6,自引:3,他引:3  
1 Introduction The Loess Plateau situated in northern China covers the drainage basins in the middle reaches of the Yellow River. It starts from the western piedmont of Taihang Mountains in the east, reaches the eastern slope of the Wushao and Riyue mountains, connects the northern part of the Qinling Mountains in the south and borders the Great Wall in the north, covering an area of about 380,000 km2 (Figure 1). The region is overlain extensively by Quaternary loess in great thickness, …  相似文献   

2.
The capacity of soil and water conservation measures, defined as the maximum quantity of suitable soil and water conservation measures contained in a region, were determined for the Loess Plateau based on zones suitable for establishing terraced fields, forestland and grassland with the support of geographic information system (GIS) software. The minimum possible soil erosion modulus and actual soil erosion modulus in 2010 were calculated using the revised universal soil loss equation (RUSLE), and the ratio of the minimum possible soil erosion modulus under the capacity of soil and water conservation measures to the actual soil erosion modulus was defined as the soil erosion control degree. The control potential of soil erosion and water loss in the Loess Plateau was studied using this concept. Results showed that the actual soil erosion modulus was 3355 t?km-2?a-1, the minimum possible soil erosion modulus was 1921 t?km-2?a-1, and the soil erosion control degree was 0.57 (medium level) in the Loess Plateau in 2010. In terms of zoning, the control degree was relatively high in the river valley-plain area, soil-rocky mountainous area, and windy-sandy area, but relatively low in the soil-rocky hilly-forested area, hilly-gully area and plateau-gully area. The rate of erosion areas with a soil erosion modulus of less than 1000 t?km-2?a-1 increased from 50.48% to 57.71%, forest and grass coverage rose from 56.74% to 69.15%, rate of terraced fields increased from 4.36% to 19.03%, and per capita grain available rose from 418 kg?a-1 to 459 kg?a-1 under the capacity of soil and water conservation measures compared with actual conditions. These research results are of some guiding significance for soil and water loss control in the Loess Plateau.  相似文献   

3.
硬化地面与黄土高原水土流失   总被引:3,自引:2,他引:1  
姚文波 《地理研究》2007,26(6):1097-1108
在界定硬化地面概念的基础上,进一步将硬化地面分为道路、城镇街区、农家场院三大类。并利用黄土高原400~600mm集流能力试验公式,对甘肃省陇东黄土高原沟壑区不同硬化地面的集流能力、侵蚀量进行分类实例分析研究,发现硬化地面集流能力远大于自然地面,因此城镇、道路、村庄附近的土壤侵蚀尤其严重。在黄土高原地区,不仅与之相关的沟壑的形成和发育,而且相关沟谷和河流的溯源侵蚀之力度大小也要受其影响。随着人口的增加,硬化地面面积越来越大,受其影响水土流失更加严重,这是历史时期黄土高原水土流失日益加剧的重要原因之一。今后黄土高原的水土保持工作,须将防治水土流失与解决水资源紧缺有机结合起来。其最佳解决途径,就是用硬化地面所集中的雨水,作为工农业生产和生活用水,以解决黄土高原水资源之不足。  相似文献   

4.
基于土壤侵蚀控制度的黄土高原水土流失治理潜力研究   总被引:11,自引:1,他引:10  
以整个黄土高原为研究对象,首先将水土保持措施容量定义为某一区域能容纳的最大适宜水土保持措施量。根据梯田、林地和草地的适宜布设区域,在地理信息系统(GIS)软件的支持下,确定了黄土高原的水土保持措施容量。使用修正通用土壤流失方程(RUSLE),计算了最小可能土壤侵蚀模数和2010年现状土壤侵蚀模数,并将水土保持措施容量下的最小可能土壤侵蚀模数与现状土壤侵蚀模数之比定义为土壤侵蚀控制度。随后使用土壤侵蚀控制度,对黄土高原水土流失治理潜力进行了研究。结果显示:黄土高原2010年现状土壤侵蚀模数为3355 t·km-2·a-1,最小可能土壤侵蚀模数为1921 t·km-2·a-1,土壤侵蚀控制度为0.57,属于中等水平。相比于现状条件,在水土保持措施容量条件下,微度侵蚀区比例从50.48%提高至57.71%,林草覆盖率从56.74%增加至69.15%,梯田所占比例由4.36%增加到19.03%,人均粮食产量可从418 kg·a-1提高至459 kg·a-1。研究成果对于黄土高原生态文明建设具有一定的指导意义。  相似文献   

5.
黄土高原典型地区土壤侵蚀共性与特点   总被引:19,自引:1,他引:19  
通过对黄土高原典型地区土壤侵蚀以往的研究结论进行综合分析,在比较土壤侵蚀相似性和差异性的基础上,对这些典型地区土壤侵蚀的共性与特点进行了研究,结果表明:1、黄土高原典型地区土壤侵蚀影响因素有降雨、地形及土地利用;2、黄土高原各典型地区主要侵蚀类型为水蚀及重力侵蚀;主要侵蚀发生时间为汛期;主要侵蚀空间分布特征为具有垂直分带性;3、绥德地区侵蚀产沙强烈,天水地区侵蚀相对轻微,安塞地区各种侵蚀特征典型。西峰地区土壤侵蚀特殊。  相似文献   

6.
Soil erosion is a major threat to our terrestrial ecosystems and an important global environmental problem. The Loess Plateau in China is one of the regions that suffered more severe soil erosion and undergoing climate warming and drying in the past decades. The vegetation restoration named Grain-to-Green Program has now been operating for more than 10 years. It is necessary to assess the variation of soil erosion and the response of precipita- tion and vegetation restoration to soil erosion on the Loess Plateau. In the study, the Revised Universal Soil Loss Equation (RUSLE) was applied to evaluate annual soil loss caused by water erosion. The results showed as follows. The soil erosion on the Loess Plateau between 2000 and 2010 averaged for 15.2 t hm-2 a 1 and was characterized as light for the value less than 25 t hm-2 a-1. The severe soil erosion higher than 25 t hm-2 a-~ was mainly distributed in the gully and hilly regions in the central, southwestern, and some scattered areas of earth-rocky mountainous areas on the Loess Plateau. The soil erosion on the Loess Plateau showed a deceasing trend in recent decade and reduced more at rates more than 1 t hm 2 a 1 in the areas suffering severe soil loss. Benefited from the improved vegetation cover and ecological construction, the soil erosion on the Loess Plateau was significantly declined, es- pecially in the east of Yulin, most parts of Yah'an prefectures in Shaanxi Province, and the west of Luliang and Linfen prefectures in Shanxi Province in the hilly and gully regions. The variation of vegetation cover responding to soil erosion in these areas showed the relatively higher contribution than the precipitation. However, most areas in Qingyang and Dingxi pre- fectures in Gansu Province and Guyuan in Ningxia Hui Autonomous Region were predomi- nantly related to precipitation.  相似文献   

7.
Developing an effective approach to rapidly assess the effects of restoration projects on soil erosion intensity and their extensive spatial and temporal dynamics is important for regional ecosystem management and the development of soil conservation strategies in the future. This study applied a model that was developed at the pixel scale using water soil erosion 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 coverage maps. The slope gradient maps were calculated based on data from the digital elevation model. The area of water soil-eroded land was classified into six grades by integrating slope gradients, land use and vegetation coverage. Results show that the Grain-To-Green Project in the Loess Plateau worked based on the land use changes from 2000 to 2010 and 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 significantly decreased 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 provinces to the total soil-eroded area in the Loess Plateau and the composition of the soil erosion intensity level in each province are different. Lands with severe, more severe and extremely severe soil erosion intensities are mainly distributed in Qinghai, Ningxia, Gansu and Inner Mongolia. These areas, although relatively small, must be prioritised and preferentially treated.  相似文献   

8.
Soil erosion assessment and prediction play critical roles in addressing problems associated with erosion control or soil conservation. The past dynamics of soil erosion can provide valuable information for us to understand the relations of soil erosion to environmental change and anthropogenic activity. The present paper has compared Holocene climatic changes in northwestern China with those in southern Norway, and investigated the past dynamics of erosion activity during the Holocene. Modern soil erosion on the Loess Plateau is a combination of the intensive natural erosion and human-induced erosion, the latter being four times greater than the former. Because of global warming and increasing human activities, climate on the Loess Plateau is becoming dryer and more unstable, causing an enhanced erosion problem and water scarcity. In the arctic-alpine region of southern Norway, however, the global warming and regional wetting caused expansion of the largest European ice cap. This has accentuated the erosion in that region, with a higher frequency of avalanches and debris flows.  相似文献   

9.
Soil erosion assessment and prediction play critical roles in addressing problems associated with erosion control or soil conservation. The past dynamics of soil erosion can provide valuable information for us to understand the relations of soil erosion to environmental change and anthropogenic activity. The present paper has compared Holocene climatic changes in northwestern China with those in southern Norway, and investigated the past dynamics of erosion activity during the Holocene. Modern soil erosion on the Loess Plateau is a combination of the intensive natural erosion and human-induced erosion, the latter being four times greater than the former. Because of global warming and increasing human activities, climate on the Loess Plateau is becoming dryer and more unstable, causing an enhanced erosion problem and water scarcity. In the arctic-alpine region of southern Norway, however, the global warming and regional wetting caused expansion of the largest European ice cap. This has accentuated the erosion in that region, with a higher frequency of avalanches and debris flows.  相似文献   

10.
黄土高原土壤侵蚀规律研究工作回顾   总被引:16,自引:1,他引:16  
陈永宗 《地理研究》1987,6(1):76-85
1950年以来,黄土高原土壤侵蚀规律研究工作已建立了完整的分类系统,进行了侵蚀区划,查明了黄河泥沙及其中的粗泥沙来源。定量评价了各自然因子和人为因子与侵蚀量的关系。黄河自古多沙,而近期更加强烈。指出了过去研究工作中的主要问题。  相似文献   

11.
黄土高原侵蚀期研究   总被引:22,自引:12,他引:10  
赵景波  杜娟  黄春长 《中国沙漠》2002,22(3):257-261
黄土高原在沉积的同时也存在着侵蚀,主要是流水、重力等因素造成的。这种侵蚀会受到气候、构造运动以及人类活动控制。资料显示,黄土高原存在3种基本的侵蚀期,一是气候侵蚀期,二是构造侵蚀期,三是人为因素侵蚀期。此外还有气候与构造共同作用产生的侵蚀期和构造与人类共同作用产生的侵蚀期。温湿期风尘堆积少,降水量增多,流水动力增强,是黄土高原理论上的侵蚀期。构造抬升引起侵蚀基准面下降,进而导致黄土高原加快侵蚀,出现构造侵蚀期。人类活动破坏了黄土高原的植被和土层结构,导致黄土高原侵蚀加剧,从而出现了人类因素引起的现代侵蚀加速期。在黄土发育的冷干期,由于植被稀疏,侵蚀量大于温湿期,但堆积量远大于侵蚀量。要改变现代侵蚀状况,就应当加强黄土高原生态环境治理。  相似文献   

12.
区域土壤侵蚀演化风险分析——以泾河流域为例   总被引:2,自引:0,他引:2  
李勋贵  魏霞 《地理研究》2011,30(8):1361-1369
土壤侵蚀演化风险是在一定的空间范围内土壤侵蚀风险的时间变化关系,是发生土壤侵蚀可能性的动态演变过程,其对于评价不同时空尺度水土保持措施的合理性及其效益意义重大。以位于黄土高原中部的泾河流域为例,基于1986年、1995年和2000年的三期土地利用类型空间数据,利用GIS技术和信息熵理论,结合美国通用土壤流失方程(Uni...  相似文献   

13.
黄土高原沟道流域产沙过程的初步分析   总被引:21,自引:6,他引:21  
陈永宗 《地理研究》1983,2(1):35-47
黄土高原的主要产沙地区是河口镇至龙门黄河干流两侧和泾、洛、渭河中上游,产沙时间集中7—9月或一、二次暴雨期。流域产沙量与河道断面输沙量基本一致。产沙最与降雨量加径流深组合因子成正比相关,并随坡度增大而增加,坡度超过25—28度水流面蚀强度减弱。砂黄土的可蚀性最大,黄土其次,粘黄土最小。灌木林的防蚀效果最好。近三十年来黄土高原的产沙量进一步增加,其中由人类活动而增加的沙量约占黄河平均输沙量的23~35%。沟道流域的产沙过程具有垂直分带规律。沟间地以细沟侵蚀产沙为主,沟谷地是水力、重力和洞穴侵蚀综合作用的场所。黄土丘陵区沟谷地的产沙量此沟间地大59.0%左右;黄土塬区产生的泥沙绝大部来自沟谷地。  相似文献   

14.
甘肃黄土高原区生态建设与可持续农业发展对策   总被引:11,自引:6,他引:11  
通过对甘肃黄土高原区的生态环境现状和成因的分析,指出是人类的掠夺性行为加速了本区脆弱生态环境的恶变,并提出了甘肃黄土高原区生态环境建设与可持续农业发展的对策。  相似文献   

15.
王钧  李广  聂志刚  刘强 《干旱区地理》2020,43(2):398-405
针对陇中黄土丘陵沟壑区土壤水蚀过程复杂且难以有效预测的问题,以定西市安家沟水土保持试验站2005—2016年1~12月人工草地径流场试验数据为主要来源,将流域月降雨量、月侵蚀性降雨量、月径流量、月降雨强度、径流场面积、径流场坡度、土壤砂粒含量、土壤粘粒含量8个因子作为输入因子,月土壤水蚀量作为输出,运用偏最小二乘法(Partial Least-Squares Regression,PLSR)和长短期记忆(Long Short-Term Memory,LSTM)循环神经网络建立人工草地土壤水蚀预测模型,并利用BP(Back Propagation)、RNN(Recurrent Neural Network)、LSTM常见神经网络模型,对模型的有效性进行评估。结果表明:PLSR将模型8个输入因子减少为4个,从而有效解决LSTM神经网络模型对样本数量要求过高的问题; PLSR和LSTM神经网络模型的结合可以有效提高模型对人工草地土壤水蚀过程的预测精度和收敛速度,预测结果的平均相对误差小于4%,相关系数高于其他3种神经网络模型,而迭代次数、均方根误差和平均绝对误差均低于其他3种模型;研究发现坡度对人工草地土壤水蚀过程影响较为明显,降雨量小于25 mm时,人工草地土壤水蚀量不会随坡度增加而明显增长,但当降雨量超过25 mm时,人工草地土壤水蚀量会随坡度明显增加。 PLSR LSTM神经网络土壤水蚀预测模型可以准确预测陇中黄土丘陵沟壑区人工草地土壤水蚀量,为该地区水土流失的准确预报提供新的思路和方法。  相似文献   

16.
Threshold is a limit and marginal point when a qualitative change takes place. Since threshold principle was firstly used in landform research by S.A.Schumm in the 1970s, the quantitative research on watershed landform development stage has come true. Davis proposed a three-stage model on landform evolution: young, mature and old stages. Thereafter Strahler quantified this model by hypsometric analysis method. The authors thought that the material movement stage cannot be expressed by hypsometric method in watershed landform at development stage, because of the uncertainty on stage delimitation. To meet this shortcoming, this paper presents an integral erosion value method. A clear delimitation on landform development stage in the Loess Plateau region has been tested by this method. The result shows that gullied loessial hilly area is at the mature stage, and gullied loessial tableland area is at the young stage. It is estimated that from the point of erosion related sediment yield, natural erosion accounts for 70% of the total erosion amount, and artificial accelerating erosion is 30%. Therefore soil and water conservation is very crucial for the Loess Plateau.  相似文献   

17.
Threshold is a limit and marginal point when a qualitative change takes place.Since threshold principle was firstly used in landform research by S.A.Schumm in the 1970s,the quantitative research on watershed landform development stage has come true.Davis proposed a three-stage model on landform evolution:young ,mature and old stages.Thereafter Stahler quantified this model by hypsometric analysis method.The authors thought that the material movement stage cannot be expressed by hypsometric method in watershed landform at development stage,because of the uncertainty on stage delimitaion.To meet this shortcoming,this paper presents an integral erosion value method.A clear delimitation on landform development stage in the Loess Plateau region has been tested by this method.The result shows that gullied loessial hilly area is at the mature stage,and gullied loessial tableland area is at the young stage.It is estimated that from the point of erosion related sediment yield,natural erosion accounts for 70% of the total erosion amount,and artificial accelerating erosion is 30%.Therefore soil and water conservation is very crucial for the Loess Plateau.  相似文献   

18.
郑兴年  王乃斌 《地理学报》1993,48(2):161-170
本文利用遥感技术通过典型区的分析,对黄土高原土地退化现状及其成因过程进行了深入研究。结果表明,黄土高原地区由于特殊的自然条件,加以长期人类活动影响,土地退化十分严重,并处于不断发展之中,主要表现为水土流失和土地沙化等。  相似文献   

19.
梯田建设和淤地坝淤积对土壤侵蚀影响的定量分析   总被引:8,自引:0,他引:8  
为了研究梯田建设和淤地坝淤积对流域土壤侵蚀的影响,本文首先建立了包含梯田、坡耕地、陡坡草地以及坝地在内的黄土高原丘陵沟壑区流域简化模型,并定义了流域的先锋期、过渡期以及顶级期三个状态,使用修正通用土壤流失方程(RUSLE) 分析了不同时期的流域土壤侵蚀模数。结果显示:先锋期与顶级期是流域水土保持治理的极限状态,先锋期峁边线上部土壤侵蚀模数为299.56 t×hm-2×a-1,下部土壤侵蚀模数为136.64 t×hm-2×a-1,平均侵蚀模数为229.74 t×hm-2×a-1;顶级期峁边线上部土壤侵蚀模数为39.10 t×hm-2×a-1,下部土壤侵蚀模数为1.10 t×hm-2×a-1,平均侵蚀模数为22.81 t×hm-2×a-1;在过渡期,随着梯田面积比例的增加,峁边线上部土壤侵蚀模数呈指数减少,而随着淤积高度的增加,峁边线下部土壤侵蚀模数呈线性减少,文章最后对这一结论进行了实证分析。  相似文献   

20.
The preservation and sustainable development of soil and water resources is one of the basic principles for the development of China. Throughout the course of history, all the social improvement and economic development are deeply concerned with soil loss and ecological environmental protection. It is now a common sense that soil and water conservation is the safety insurance for national ecology and its development. For the past long period of time, soil and water loss has been recognized as "the No.1 killer" to the ecological environment. The nation is on the stage of the critical conditions for its development. China has massive mountain and upland area with complicated geological conditions and accelerated human destruction and serious soil and water loss. Based on rich historical documents, renovating experience and detailed analysis of the data collected in field experiments and field surveys for soil and water conservation, this paper aims to review the general characteristics of soil and water loss, to explore the relationship between soil and water conservation and sustainable economic development, and to provide relevant strategies for soil and water conservation in China.  相似文献   

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