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1.
Soil erosion has become a serious environmental problem worldwide, and slope land is the main source of soil erosion. As a primary cover of slope land, crops have an important influence on the occurrence and development of runoff and soil erosion on slope land. This paper reviews the current understanding of runoff and soil erosion on slope cropland. Crops mainly impact splash detachment, slope runoff, and sediment yield. In this review paper, the effects of crop growth and rainfall on the splash detachment rate and the spatial distribution of splash detachment are summarized. Crop growth has a significant impact on runoff and sediment yield. Rainfall intensity and slope gradient can influence the level of erosive energy that causes soil erosion. Furthermore, other factors such as antecedent soil water content, soil properties, soil surface physical crust, and soil surface roughness can affect soil anti-erodibility. The varying effects of different crops and with different influence mechanisms on runoff and soil erosion, as well as changes in their ability to influence erosion under different external conditions should all remain focal points of future research. The effect of crop vegetation on runoff and soil erosion on slope land is a very important factor in understanding large-scale soil erosion systems, and in-depth study of this topic is highly significant for both theory and practice. 相似文献
2.
A review of runoff generation and soil erosion across scales in semiarid south-eastern Spain 总被引：3，自引：0，他引：3
Y. Cantón A. Solé-Benet J. de Vente C. Boix-Fayos A. Calvo-Cases C. Asensio J. Puigdefábregas 《Journal of Arid Environments》2011,75(12):1254-1261
Climate, lithology, soil and especially, intense land use/cover changes, make SE Spain very vulnerable to runoff generation and water erosion leading to loss of nutrients and organic matter and to infrequent but devastating floods, reservoir siltation and mass failures. This susceptibility has led to heavy economic investment and research efforts since the 1980s, making this region a worldwide reference for understanding the hydrology and geomorphology of semiarid ecosystems. Runoff and soil erosion have been intensively studied throughout the last decades in various natural ecosystems as well as in abandoned farmlands. Research has considered a wide range of methods and spatial and temporal scales. This paper reviews the methods and data describing runoff generation and water erosion, synthesising the key processes involved, rates, thresholds and controlling factors from a scale-dependent perspective. It also identifies the major gaps in current knowledge to provide recommendations for further research towards solutions that reduce the negative impacts of erosion. Research in SE Spain has contributed significantly to a better understanding of the effect of spatial and temporal scale on runoff and sediment yield measurements, and highlighted the important role of distinct erosion and sediment transport processes, hydrologic connectivity, spatial and temporal patterns of rainfall, the occurrence of extreme events and the impacts of land use changes. The most effective ways and challenges to predict runoff, soil erosion and sediment yield at the catchment scale are also discussed. 相似文献
3.
基于TETIS模型的黑土区乌裕尔河流域径流与侵蚀产沙模拟研究 总被引：1，自引：0，他引：1
为科学地认识中国东北黑土区流域土壤侵蚀特征,探讨TETIS模型在该区的适用性,本文以乌裕尔河流域为例,利用1971-1987年日径流与泥沙实测数据对TETIS模型进行了校正与验证,进而分析了流域土壤侵蚀强度特征及其与坡度、土地利用方式的关系。研究结果表明：TETIS模型在乌裕尔河流域适用性好,日径流与日输沙量的纳什效率系数在0.52~0.70之间,决定系数在0.60~0.71之间,体积误差均不超过15%。流域平均侵蚀模数为397.2 t/(km2·a),流域以微度和轻度侵蚀为主,约90%的产沙来自于坡面。平均土壤侵蚀模数随坡度的增大而增大,流域侵蚀量主要来自于0°~5°坡面。不同土地利用方式具不同的土壤侵蚀模数,耕地土壤侵蚀模数最大,达556.3 t/(km2·a)。坡度较大的耕地和植被覆盖度较低的区域是水土流失治理的重点。研究表明,TETIS模型在黑土区模拟土壤侵蚀产沙应用前景好,可为研究区制定水土保持措施提供科学依据。 相似文献
4.
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
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
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Modelling runoff and erosion for a semi-arid catchment using a multi-scale approach based on hydrological connectivity 总被引：1，自引：0，他引：1
Runoff and erosion processes are often non-linear and scale dependent, which complicate runoff and erosion modelling at the catchment scale. One of the reasons for scale dependency is the influence of sinks, i.e. areas of infiltration and sedimentation, which lower hydrological connectivity and decrease the area-specific runoff and sediment yield. The objective of our study was to model runoff and erosion for a semi-arid catchment using a multi-scale approach based on hydrological connectivity. We simulated runoff and sediment dynamics at the catchment scale with the LAPSUS model and included plot and hillslope scale features that influenced hydrological connectivity. The semi-arid Carcavo catchment in Southeast Spain was selected as the study area, where vegetation patches and agricultural terraces are the relevant sinks at the plot and hillslope scales, respectively. We elaborated the infiltration module to integrate these runoff sinks, by adapting the parameters runoff threshold and runoff coefficient, which were derived from a rainfall simulation database. The results showed that the spatial distribution of vegetation patches and agricultural terraces largely determined hydrological connectivity at the catchment scale. Runoff and sediment yield for the scenario without agricultural terraces were, respectively, a factor four and nine higher compared to the current situation. Distributed hydrological and erosion models should therefore take account of relevant sinks at finer scales in order to correctly simulate runoff and erosion-sedimentation patterns. 相似文献
7.
为了明确土壤性质对坡面侵蚀方式作用机制的影响,本研究采用室内模拟降雨试验,选取黄土高原典型暴雨强度,在不同坡度条件下,对两种黄土的坡面侵蚀方式、形态特征、产流产沙过程及其相应径流流速的变化规律进行了研究。结果表明,绥德土径流量明显高于安塞土,10º、15º和20º时前者的平均径流量分别比后者高出51.1%、55.5%和63.0%,且前者更易形成细沟,使得其平均含沙量和平均产沙率分别是后者的1.14~3.59倍和2.50~8.48倍。在片蚀阶段,与绥德土相比,安塞土的含沙量较高,后者的平均含沙量是前者的1.24~1.73倍,但两种土壤的含沙量和产沙规律相同,均表现为先快速增加到最大值,然后逐渐降低到相对稳定状态,该现象证明片蚀的初期阶段主要受控于径流输沙能力,后期受径流的剥蚀能力控制。在细沟侵蚀阶段,绥德土细沟发育以沟头溯源侵蚀为主,崩塌作用频繁,该侵蚀形式不仅控制着细沟形态的总体特征,也导致含沙量和产沙率均急剧增加,该阶段平均含沙量是相应片蚀阶段的3.25~4.34倍。细沟沟口下方坡面存在明显的泥沙沉积带,表明细沟集中水流的搬运能力远高于坡面漫流,细沟侵蚀主要受径流输沙能力控制。两种土壤的径流流速均表现为坡面下部高于坡面上部,径流稳定后高于径流稳定前,总体来看,绥德土和安塞土上坡和径流稳定后的平均流速分别是下坡和径流稳定前的1.4倍、1.25倍和1.75倍、1.29倍,此外细沟侵蚀或侵蚀强度与微地貌形态之间的互馈作用对径流流速也有较大影响。 相似文献
8.
《Geomorphology》1997,18(2):61-75
In badland areas of the Ebro Basin, in a semiarid climate, two erosion plots (257 m2; 5° slope and 128 m2; 23° slope) on exposed Tertiary clays were monitored over two years (Nov. 1991–Nov. 1993). This material is characterized by high sodium absorption ratios which lead to high soil dispersivity. The dominant erosion processes in both plots are rilling and sheet erosion. Rainfall intensity was recorded at a weather station, connected to a data-logger, sediment production for single events was collected in tanks, and ground lowering was measured every six months by erosion pins and microtopographic profile gauge techniques. Significant runoff was produced only by rainfall events above 5 mm. Another threshold at 20 mm rain was noted. For rainfalls higher than 20 mm, the 23° slope plot shows a greater runoff response than the 5° one. Rainfall events exceeding this threshold showed a higher sediment production for the steeper slope. In the relationship between precipitation and sediment concentration, an envelope curve can be drawn indicating that any rainfall event of a given amount and intensity has a maximum sediment concentration which we speculate to be a function of the runoff sediment transport capacity. Runoff response and sediment yield in the studied plots are controlled by the rainfall and soil characteristics and their seasonal variations. In both plots, the erosion pins show that erosion rates in rill areas are 25–50% higher than in the interrill areas. Sediment yield recorded by collector devices was higher than the rates measured by erosion pins. The erosion rates based on rill cross-sections by profilometers were higher than the ones recorded by collectors. 相似文献
9.
为进一步研究不同草本植物和边坡坡面形态对坡面产流产沙的影响,以西宁盆地毛鸡湾流域长岭绿化区作为试验区,设计了直形和阶梯形2种坡形,选取3种优势草本老芒麦(Elymus sibiricus Linn.)、垂穗披碱草(Elymus nutans Griseb.)和细茎冰草(Agropyron trachycaulum Linn.Gaertn.)作为试验供试种,通过人工模拟降雨试验,探讨了种植不同草本和坡形条件下,边坡坡面的产流、产沙和入渗特征。结果表明,在直形边坡中,裸坡坡面的产流时间小于种植草本植物坡面,且垂穗披碱草坡面和老芒麦坡面的形成产流时间相对较长,为4 min。与直形边坡相比,垂穗披碱草阶梯形坡面产流时间相对最长,为8 min;在直形边坡中,垂穗披碱草坡面和老芒麦坡面累积径流量、累积产沙量和径流系数相对最小,分别为51.42 L/min、160 g、14.98%,51.25 L/min、210 g、14.93%,细茎冰草坡面的累积径流量、累积产沙量和径流系数分别为96.97 L/min, 700 g, 28.25%;垂穗披碱草坡面和老芒麦坡面稳定入渗速率相对最大,其值为0.38～... 相似文献
10.
多尺度土地利用与土壤侵蚀 总被引：20，自引：5，他引：15
土地利用能够通过改变一系列的自然现象和生态过程影响土壤侵蚀,尺度不同,土地利用与土壤侵蚀的作用机制也会发生变化。本文针对坡面尺度、小流域／流域尺度和区域尺度,综述了不同尺度上土地利用对土壤侵蚀的影响研究。其中,在坡面尺度上,土地利用与土壤侵蚀的研究主要包括土地利用方式和土地管理措施对土壤侵蚀的影响,相应尺度上的模型有USLE／RUSLE、WEPP等;在小流域／流域尺度上,土地利用与土壤侵蚀的研究主要涉及土地利用结构和土地利用格局对土壤侵蚀的影响,相关的模型有LISEM、AGNPS、EUROSEM和SEDEM等;在区域尺度上土壤侵蚀评价研究主要是通过尺度上推和宏观因子评价的方法进行。多尺度土地利用与土壤侵蚀研究作为自然地理学研究中的热点问题,在进一步的研究中需要关注多尺度综合与尺度转换、土地利用政策效应、土地利用格局与土壤流失过程等方面的研究内容。 相似文献
11.
不同坡面植被空间布局对坡沟系统产流产沙影响的实验 总被引：5，自引：0，他引：5
植被在有效控制水土流失、改善生态环境中具有重要作用。为探讨坡面不同植被覆盖度、不同植被空间布局对坡沟系统侵蚀产沙的影响,以4 m长坡面(坡度为20°)和3 m长沟坡(坡度为50°)组成的坡沟系统为研究对象,采用不同放水流量(3.2 L/min、5.2 L/min)的放水冲刷实验,研究了不同放水流量、不同植被覆盖度、不同植被布设部位对坡-沟系统及沟坡侵蚀产沙的影响。结果表明,在实验条件下,不同植被布设部位在相同放水流量、相同植被覆盖度条件下对坡沟系统侵蚀产沙有明显影响,而对产流量无明显影响;沟坡部分侵蚀产沙量不随坡面植被覆盖度的增大而减小,相反呈增大趋势。说明在实验条件下,对坡沟系统而言,仅在坡面部分布设植被,尽管能在一定程度上减少坡沟系统侵蚀产沙,但并不能有效减小沟坡部分的侵蚀产沙,甚至引起沟坡部分侵蚀产沙的增大。因此,水土流失治理过程中采取有效措施进行坡沟兼治将是减少水土流失的有效手段。 相似文献
12.
Surface crusts and seals can form from a variety of processes, both physical and biological, and have the potential to alter runoff and erosion, especially in regions with low vegetation covers. Despite the obvious links between seals and crusts these features have rarely been considered together. This study uses rainfall simulation experiments to investigate interrill soil crust and seal development in response to structural (or raindrop-impact-induced) and depositional (or runoff-induced) processes on a semiarid piedmont in southern New Mexico, USA, which has undergone substantive vegetation change (replacement of grasses by shrubs) over the last 100 years. The study design incorporates six double-paired runoff plots divided into four subplots, each of which was exposed to three rainfall simulation events. Crust development on these plots was assessed using penetration-resistance measurements while seal development was assessed using runoff coefficients. The penetration-resistance data indicate that subplots directly exposed to raindrop impacts (uncovered plots) have crusts that are 40% stronger than those positioned beneath a mesh cover (covered plots) that intercepts the kinetic energy of the rainfall. The crusts exposed to raindrop-impacts increased in strength following each simulation, whereas the crusts on the covered surfaces reached a plateau after two events.Runoff data indicate that seal development does not directly mirror crust formation. Runoff coefficients increased after each rainfall simulation event but were not significantly different between the covered and uncovered plots. Rather, the presence of stone lags or litter on the soil surface influenced the relation between runoff and seal development. Sediment yields from uncovered surfaces exceeded those from covered surfaces, indicating that raindrop impacts contribute to the delivery of sediment into flows. The results of this study indicate that the loss of vegetation cover on the piedmont has increased the extent of surface crust and seal development but that those crusts may be playing an important role in mitigating erosion. 相似文献
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基于地块汇流网络的小流域水沙运移模拟方法研究 总被引：4，自引：0，他引：4
全流域逐地块水土流失计算,是目前水土保持定量评价的重要手段,其实现过程既需要有考虑地貌因子和上下游关系的土壤侵蚀模型,也需要建立全流域地块汇流网络,并与侵蚀模型有机连接。本文针对黄土高原特殊的地理条件和水土流失规律,对传统的基于栅格的小流域汇流技术进行了改进,考虑地块间上下游汇流关系,建立了基于地块的水沙汇流网络模型,模拟水沙在流域复杂下垫面的汇流过程,提取出流域各地块间的水沙汇流网络,并计算出3个重要参数:流域地块间水沙汇流的顺序、流域地块间水沙汇流数目的空间分配、水沙流经各地块的坡长。将土壤侵蚀模型按地貌部位与特征分为坡面模型、沟坡模型和沟道输移模型,与地块汇流网络有机集成,实现了水沙运移的全流域按地块沿程计算。 相似文献
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东北地区融雪期径流及产沙特征分析 总被引：10，自引：1，他引：9
严重的水土流失已威胁到东北地区的土地资源,融雪径流及其造成的侵蚀作为该地区水土流失的重要组成部分,但相关研究较少。本文利用全区93个气象站降水资料,分析了东北地区降雪与积雪的基本特征。利用27个典型流域水文站径流泥沙资料,分析了融雪期内径流与产沙特征。结果表明:东北各地雪期长度为5~8个月,自南向北逐渐延长。年降雪量占年降水总量的比例多在7~25％,由此形成的融雪期径流深占全年径流深比例达13.3~24.9％,融雪期输沙模数占全年输沙模数比例达5.8~27.7％。融雪期流域输沙模数受地貌影响十分显著:丘陵漫岗区降雪量和径流深均低于山区,但输沙模数平均为山区的2.9倍。融雪输沙模数与流域面积有十分显著的幂函数递减关系。为揭示融雪侵蚀影响因素及其作用机理,今后应加强融雪期内流域侵蚀及产沙监测。 相似文献
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Application of USLE in a GIS environment to estimate soil erosion in the Irga watershed,Jharkhand, India 总被引：1，自引：0，他引：1
Poushali Roy 《自然地理学》2019,40(4):361-383
A comprehensive methodology that integrates the Universal Soil Loss Equation (USLE) and Geographic Information System (GIS) was adopted in this study to determine the soil erosion and sediment yield of the Irga watershed in Jharkhand, India. Based on the availability and applicability of data in a GIS-environment, the original equations for the model input parameters were, however, modified by researchers. In the present study, a power-law equation was generated to estimate the rainfall erosivity (R) factor, and the Nash-Sutcliffe model efficiency coefficient used to determine the accuracy of the modified R factor. Average annual soil erosion in the Irga watershed is estimated to be 4.3 t ha?1 yr?1. On the other hand, average annual sediment yield of the watershed, estimated using the sediment delivery ratio, was found to be 1.2 t ha?1 yr?1. Low sediment yield indicates that most of the eroded soil was deposited within the watershed. 相似文献
17.
Enan M. Nyesheja Attia M. El-Tantawi Fidele Karamage Christophe Mupenzi Jean Baptiste Nsengiyumva 《自然地理学》2019,40(4):339-360
This research assessed the soil erosion threat in the Congo Nile Ridge Region of Rwanda. The study forecasted erosion by applying the Revised Universal Soil Erosion (RUSLE) with five factors (rainfall, soil, topography, cover management, and support practices) and spatial data. About 85.5% of the area under investigation was predisposed to erosion with unsustainable average soil loss rates of > 1 t/ha/yr. The outcomes of the research highlighted that the average rate of estimated soil loss in the region prone to erosion was > 63.62 t/ha/yr, resulting in an overall annual predicted soil loss of approximately 44 × 106 t in 2016. All of the districts studied have steep slope gradients (30.4%–36.1%) and high annual rainfall totals (1199–1484 mm/yr), except Rubavu district. More than 88.8% of croplands had unsustainable average soil loss rates of > 1 t/ha/yr. The analysis indicated that both terracing and strip cropping have the potential to reduce rates of soil loss in the farmland, by 64.4% and 10.4%, respectively. The results of this study will serve as a baseline for soil erosion mitigation and land-use planning in the study area and Rwanda at large. 相似文献
18.
沙层特性对沙盖黄土坡面产流产沙变化贡献的定量分析 总被引：1，自引：0，他引：1
沙盖黄土坡面产流产沙方式独特,侵蚀过程复杂,量化降雨过程中该类坡面产流产沙变化影响因素贡献的大小对揭示其侵蚀机理具有重要的意义。基于室内模拟降雨试验,定量分析沙层厚度（2 cm、5 cm和10 cm）和粒径组成（100%粒径≤ 0.25 mm、75%粒径≤ 0.25 mm +25%粒径> 0.25 mm、50%粒径≤ 0.25 mm+50%粒径> 0.25 mm、未处理原沙和100%粒径> 0.25 mm）在降雨过程中对产流产沙变化的影响和贡献。结果显示：沙层厚度增加能明显延长产流时间,减少总产流量,增加总产沙量,增大降雨过程中产流产沙的变异性;随沙层粒径组成变粗,初始产流时间和产沙量无明显变化规律,产流量有增大趋势。沙层厚度、粒径组成及二者交互作用对初始产流时间变化的贡献率分别为68.03%、15.77%和3.85%。沙层厚度对降雨不同时段15 min产流量和不同历时总产流量的贡献率分别在23.89%~52.22%和41.10%~48.94%之间,对相应产沙的贡献率分别在29.19%~62.01%和13.53%~30.31%之间。整体上沙层粒径组成变化对产流产沙量变化的贡献率小于沙层厚度,且无明显规律。沙层厚度和粒径组成交互作用对产流量和降雨中前期产沙量的影响显著（p < 0.05）,其对产流产沙变化的贡献率分别在13.12%~26.62%和3.22%~43.12%之间,不同降雨时段变化明显。研究结果说明,沙层厚度决定沙盖黄土坡面产流产沙过程,其和沙层粒径组成对产流产沙的影响和贡献随坡面沙层的侵蚀演化而动态变化,且二者的交互作用也不容忽视。 相似文献
19.
黄河内蒙古段支流“十大孔兑”侵蚀产沙的时空变化及其成因 总被引：2，自引：2，他引：0
“十大孔兑”来沙造成黄河干流强烈淤积.为了通过流域治理来减轻泥沙灾害,研究“十大孔兑”侵蚀产沙过程具有重要意义.基于1960—2005年的河流输沙量、径流量和降雨量资料,运用统计方法进行了研究.结果表明:“十大孔兑”输沙量高度集中于几个大水大沙年份,其余年份对46年总输沙量的贡献很小.最大1年、最大3年、最大5年和最大10年的累积输沙量分别占到46年总输沙量的21.26%、37.18%、47.92%和69.29%.1960—1991年和1992—2005年两个时段相比,后一时段输沙量年均值减少了37%.这一差异可以用暴雨特征的差异和下垫面(如植被)的变化来解释.1991年以后,年降水量无明显变化,但最大1日降雨量在p<0.10的水平上呈现减小的趋势.虽然20世纪90年代西柳沟并未大规模实施水土保持治理,但由于农村富余劳动力转移,对土地的压力减轻,对植被的破坏大大减弱,使得植被逐渐恢复,NDVI呈增大趋势,因而侵蚀产沙减弱.“十大孔兑”产沙模数具有明显的空间分异特征,从西向东增大,在西柳沟达到最大值,然后再减小.流域自然地理因素具有明显的变化,从西向东,沙尘暴频率减小,降雨量增大.沙丘类型也发生了变化,由以流动沙丘为主变为以半固定沙丘为主,进入河道风沙的输沙强度减小.另一方面,水力驱动的侵蚀和泥沙输移从西向东增强.上述两种作用叠加的结果,在区域中部西柳沟附近出现了侵蚀产沙的峰值区. 相似文献
20.
黄河头道拐—潼关区间植被恢复及其对水沙过程影响 总被引：1，自引：0，他引：1
黄河头道拐—潼关区间是黄河泥沙的主要来源区,也是中国植被恢复最快的地区。植被的快速恢复对径流和输沙过程产生了深远影响。本文基于250 m分辨率的归一化植被指数数据（MOD13Q1 NDVI）,使用统计分析和趋势分析技术,分析了头道拐—潼关区间不同景观单元植被恢复特点、影响因素以及其对水沙过程的影响,并对头道拐—潼关区间植被未来发展趋势进行了预测。研究结果显示：头道拐—潼关区间82.87%区域的植被呈显著增加趋势（p < 0.05）,且植被恢复速度最快的区域为半湿润的黄土丘陵沟壑区,坡度和降水量在不同景观单元下对植被恢复的影响不同。随着降水量的增加,头道拐—潼关区间NDVI和年降水量的相关性降低。在植被恢复背景下,黄河中游主要河流径流的主要影响因素仍然是降水量,输沙量同时受到降水量和植被恢复的影响,含沙量与NDVI呈现出较强的负相关关系,而与降水量的相关性较弱。随着植被覆盖度的增加,流域土壤侵蚀量降低,河流输沙量也呈降低趋势,土壤侵蚀量对河流输沙量的贡献率变化于39%~88%之间。基于植被恢复潜力和恢复速度,本文预测头道拐—潼关区间2020年、2030年、2040年以及2050年的NDVI平均值将分别达到0.68、0.75、0.79以及0.80。 相似文献