Method to predict cropland ephemeral gully erosion

Erosion of farmland due to concentrated flow is very severe on many unprotected fields across the United States. Small channels can turn into large gullies if not controlled. These small channels are routinely obliterated by tillage of the field and other routine farm operations only to be reformed again. Opposing slopes adjacent to an ephemeral gully allow runoff to reestablish a channel in approximately the same location. Since the 1960s, the Universal Soil Loss Equation (USLE) has been used to estimate rill and sheet erosion. This paper describes the Ephemeral Gully Erosion Model (EGEM). EGEM is a modification of the Agricultural Research Service Ephemeral Gully Erosion Estimate (EGEE) computer model to meet the Natural Resources Conservation Service (NRCS) needs. Limited field data obtained by NRCS were used to validate the single event component of EGEM. This paper presents a summary of these studies. There were no data available at the time of the model development to validate the average annual concept of the model. ARS conducted validation studies for the EGEE model.     

Relationships between rainfall characteristics and ephemeral gully erosion in a cultivated catchment in Sicily (Italy)

Recent research has shown a lack of long-term monitoring for detailed analysis of gully erosion response to climate characteristics. Measures carried out from 1995 to 2007 in a wheat-cultivated area in Raddusa (Sicily, Italy), represent one of the longest series of field data on ephemeral gully, EG, erosion. The data set collected in a surface area of almost 80 ha, permits analysis of the influence of rainfall on EG formation and development. Ephemeral gullies formed in the study area were measured on a yearly scale with a Post-Processing Differential GPS for length and with a steel tape for the width and depth of transversal sections. Ephemeral gully formation was observed for 8 years out of 12, which corresponds to a return period of 1.5 years. The measurements show strong temporal variability in EG erosion, in agreement with the rainfall characteristics. The total eroded volumes ranged between 0 and ca. 800 m³ year⁻¹, with a mean of ca. 420 m³ year⁻¹, corresponding to ca. 0.6 kg m⁻² year⁻¹. Ephemeral gully erosion in the study area is directly and mainly controlled by rainfall events. An antecedent rainfall index, the maximum value of 3-days rainfall (H_max3_d), is the rain parameter which best accounts for EG erosion. This index is used here as a simple surrogate for soil water content. An H_max3_d threshold of 51 mm was observed for EG formation. The return period of the H_max3_d threshold is almost the same as the return period for EG formation. Although a mean of seven erosive rain events were recorded in a year, EG formation and development generally occur during a single erosive event, similarly to other semiarid environments. The most critical period is that comprised between October and January, when the soil is wetter and the vegetation cover is scarce. Empirical models for EG eroded volume estimation were obtained using the data set collected at this site. A simple power-type equation is proposed to estimate the eroded volumes using H_max3_d as an independent variable. This equation shows an R² equal to 0.67 and a standard error of estimation of 0.79.     

Accuracy of methods for field assessment of rill and ephemeral gully erosion

To properly assess soil erosion in agricultural areas, it is necessary to determine precisely the volume of ephemeral gullies and rills in the field by using direct measurement procedures. However, little information is available on the accuracy of the different methods used. The main purpose of this paper is to provide information for a suitable assessment of rill and ephemeral gully erosion with such direct measurement methods. To achieve this objective: a) the measurement errors associated to three methods used for field assessment of channel cross sectional areas are explored; b) the influence of the number of cross sections used per unit channel length on the assessment accuracy, is analysed and; c) the effect of the channel size and shape on measurement errors is examined. The three methods considered to determine the cross sectional areas were: the micro-topographic profile meter (1); the detailed measurement of section characteristic lengths with a tape (2); and the measurement of cross section width and depth with a tape (3). Five reaches of different ephemeral gully types 14.0 or 30.0 m long and a set of six 20.4 to 29.4 m long rill reaches were selected. On each gully reach, the cross sectional areas were measured using the three above mentioned methods, with a separation (s) between cross sections of 1 m. For rills, the cross sectional areas were measured with methods 1 and 3, with s = 2 m. Then, the corresponding total erosion volumes were computed. The volume calculated with method 1 with s = 1 m for gullies and s = 2 m for rills was taken as the reference method. For each channel, and for each one of the possible combinations of s and measurement method (m), the relative measurement error and the absolute value of the relative measurement error (E_sm^r and |E_sm^r|), defined with respect to the reference one, was calculated. |E_sm^r| much higher than 10% were obtained very easily, even for small s values and for apparently quasi prismatic channels. Channel size and shape had a great influence on measurement errors. In fact, the selection of the more suitable method for a certain gully shape and size seemed to be much more important than s, at least when s < 10 m. Method 1 always provided the most precise measurements, and its results were the less dependent on s. However, s must be < 5 m to guarantee an error smaller than 10%. Method 2 is not recommended, because it is difficult, time consuming and can lead to large errors. Method 3 seems to be enough for small, wide and shallow gullies, and for small rills, but only if s is shorter than 5 m. Results obtained after the analysis of rill measurement errors were similar to those of gullies. The analysis of E_sm^r and |E_sm^r| when calculating channel volumes using a unique representative cross section highlighted the importance of correctly selecting the adequate cross section. Due to the high error values that this method can entail, it is not considered as advisable whenever accurate erosion measurements are pursued.     

Ephemeral gully erosion in northwestern Spain

This study aimed to describe types of ephemeral gullies and to determine their origin, evolution and importance as sediment sources in A Coruña province (northwest Spain). Ephemeral gullies and/or rills have been measured in a representative sample of medium-textured soils, most prone to crusting, developed over basic schist. This sample consisted of 11 small sites, ranging from 0.63 to 7.34 ha. A case study of concentrated (rill+gully) erosion in a 0.47-ha catchment with coarse-textured soils developed over granite was also reported. The mean slope of the sites studied ranged from 6.1% to 16.8%. Main periods when soil surface was poorly covered were late spring (maize seedbeds) and late autumn–early winter (grassland and winter cereal seedbeds). Case studies where fields were left bare in winter were also investigated. Soil incision and channel formation were observed even with relatively low rainfall intensities when the soil surface was sealed, but also after a single short intense rainfall event on recently tilled surfaces. Concentrated erosion took place mainly on seedbeds and newly tilled soils in late spring and by autumn or early winter, but gullies also appeared in other seasons when the soil surface was left bare. In most of the cases studied, ephemeral gully erosion caused significant soil losses, ranging between 2 and 5 m³/ha for a single season to locally, over 25 m³/ha. Gully development was significantly affected by agricultural operations, such as lineal elements often acting as initial axes of concentrated erosion. Main gullies tended to reappear at the same position.     

上方来水来沙对浅沟侵蚀产沙及水动力参数的影响

 浅沟侵蚀是黄土高原重要的侵蚀类型,上方汇水对坡面浅沟侵蚀具有重要的影响。采用野外放水冲刷试验,定量分析26°坡耕地在上方来水量为5、10和15L/min时对坡下方浅沟侵蚀产沙及其水动力参数的影响。结果表明：上方来水的汇入使浅沟水流流速明显增大,雷诺数、弗劳德数、水流功率和剪切力分别增大33%～76%、21%～47%、29%～72%和18%～42%,阻力系数减少11%～13%,导致浅沟侵蚀产沙量明显增大;除流速和弗劳德数外,其余水动力参数随放水时间的延长呈递增趋势;上方来水使浅沟侵蚀产沙量相对增量与水流功率和剪切力相对增量均呈幂函数关系。     

黄土丘陵沟壑区浅沟水流水动力学参数实验研究

浅沟侵蚀是黄土丘陵沟壑区重要的侵蚀类型,浅沟水流的水动力学参数研究是建立浅沟侵蚀物理模型或概念模型的基础。以黄土丘陵沟壑区延安市燕儿沟小流域的坡地为对象,通过野外放水冲刷实验,对浅沟水流的水动力学参数变化特征进行研究。结果表明：浅沟水流属于紊流范围,大多数情况下是急流;在坡度18°左右时,携沙水流的流速最小,阻力最大,此时水流的能量分配在侵蚀与携沙之间达到平衡;浅沟水流在坡度26°左右时流速达到最大,水流功率达到最大,最利于浅沟侵蚀的发生和发展。研究结果可为黄土区浅沟侵蚀物理模型的建立提供理论支撑。     

基于RS和GIS的黄土丘陵沟壑区浅沟侵蚀地形特征研究

为了解黄土高原浅沟侵蚀地形特征,基于Qucickbird高分辨率遥感影像和数字高程模型,提取了坡面浅沟及其地形参数,并对浅沟侵蚀的地形特征参数和分布规律进行了统计分析,结果表明：黄土丘陵沟壑区,坡面坡度、长度、坡向以及上坡长度是影响坡面浅沟数量的主要地形要素,而浅沟侵蚀地形特征主要由坡面坡度、坡面长度、上坡长度和汇流面积共同决定;坡面长度与浅沟平均长度呈显著线性关系,坡面坡度与浅沟频度、浅沟坡度与其上坡长度间则均满足二次曲线;发生浅沟侵蚀的上限与下限临界坡度分别介于26～27°和15～20°,临界坡长介于50～80 m;由浅沟坡度的正弦值与汇流面积确定出浅沟分布的临界曲线;阳向坡面的平均浅沟长度小于阴向坡面。基于RS和GIS技术能有效确定浅沟侵蚀地形特征,为黄土区坡面水土流失治理提供了技术支撑。     

非恒定流对浅沟侵蚀产沙及水动力参数的影响

浅沟侵蚀是黄土高原独特的侵蚀类型,在坡面侵蚀中占有重要的地位。关于浅沟侵蚀的研究,以往多采用恒定流量进行冲刷试验,而在实际中流量是变化的,有关非恒定流的浅沟侵蚀实验尚未见报道。采用野外放水冲刷试验,定量分析10～15、15～20、20～25 L/min 3个非恒定流的放水流量级和10、15、20 L/min 3个恒定流量的放水流量级对14°坡耕地坡面浅沟侵蚀产沙及其水动力参数的影响。结果表明:恒定流量级的流速、雷诺数、弗劳德数、剪切力、水流功率和径流含沙量分别较变流量后的非恒定流小6.64%～13.44%、2.73%～8.26%、6.15%～49.59%、0.27%～10.27%、4.27%～15.77%和2.02%～19.36%;恒定流的阻力系数则较与其相对应的非恒定流增大23.45%～43.41%。     

Upslope inflow,hillslope gradient and rainfall intensity impacts on ephemeral gully erosion

Ephemeral gullies (EGs) are major contributors to sediment loss and land degradation on cultivated lands. However, the topography and rainfall impacts on EG development processes are still unclear, especially on steep loessial hillslopes such as the Loess Plateau. A series of laboratory rainfall simulation experiments were conducted to investigate the impacts of topographic characteristics (3 typical slope gradients (S ): 26.8%, 36.4%, and 46.6%; and 5 upslope drainage areas (A ): 16, 32, 64, 96, and 128 m²) and rainfall intensities (3 representative erosive rainfall intensities 50, 75, and 100 mm hr⁻¹) on EG erosion on a steep loessial hillslope. A large slope adjustable soil pan (8 m‐long, 2 m‐wide, and 0.6 m‐deep) and a side‐sprinkler rainfall simulation system were used in this study. The results showed that soil loss increased when rainfall intensity, slope, and upslope drainage area increased. Upslope topography and inflow had great impacts on downslope EG erosion, and the contribution percentages ranged from 52.2% to 74.1%, from 48.3% to 71.4%, and from 29.5% to 66.7% for the 50, 75, and 100 mm hr⁻¹ rainfall treatments, respectively. Runoff velocities with upslope inflow were 22.7% to 79.4% larger than those without inflow, and the upslope inflow was more effective than rainfall intensity in increasing runoff velocities in EG channels, thus caused more soil erosion. Soil loss equation based on rainfall intensity and AS ² (product of the upslope drainage area and the square of the local slope gradient) was established and validated. The determination coefficient (R ² ) and Nash–Sutcliffe simulation efficiency (E _NS ) were 0.80 and 0.87, which showed satisfactory accuracy. This equation can be used to predict the EG erosion in various topographic and rainfall conditions on steep loessial hillslopes.     

根系密度对黄土塬沟头溯源侵蚀产沙和形态演化过程的影响

为明确根系密度对黄土塬沟壑区沟头溯源侵蚀产沙和形态演化过程的影响,采用野外"人工模拟降雨+放水冲刷"试验方法,以裸地试验小区(CK)为对照,研究冰草根系密度试验小区(株行距:20 cm×20 cm,C1;15 cm×15 cm,C2;10 cm×10 cm,C3)的沟头溯源侵蚀产沙过程、沟头溯源距离、沟道下切深度及发育面积等特征。结果表明:1)与对照小区相比,草被小区(C1~C3)产沙量分别降低64.32%、70.31%、69.92%;冰草株行距为15 cm×15 cm时,减沙效益最大。2)对照小区沟头溯源侵蚀过程主要包括沟口形成、贴壁流侵蚀、跌水侵蚀和沟岸崩塌等;而草被小区沟头溯源侵蚀则由贴壁流侵蚀、跌水侵蚀和根土复合体崩塌导致,崩塌是草地沟头溯源的主要原因;各根系密度下沟头溯源距离与时间均呈极显著幂函数关系;与对照相比,草被小区沟头溯源距离缩短75.61%~78.87%。3)对照小区侵蚀沟纵断面呈阶梯形,存在缓冲平台,沟头近似矩形;草被小区则呈梯形和圆弧状。与对照相比,草被小区沟道平均下切深度加深1.64~1.92倍;沟道面积随根系密度增加而缩小,草被小区沟道面积较裸地缩小68.0%~74.0%。结果可为该区"固沟保塬"工作的实施提供科学参考。     

黄土丘陵小流域蒸散发和水分平衡对植被恢复的影响

Evapotranspiration, soil moisture balance and the dynamics in a gully catchment of the Loess Plateau in China were determined with 6 land use treatments including natural grassland, shrubs （Caragana rnicrophylla）, two woodlands （Prunus armeniaca var. ansu and Pinus tabulaeformis）, cultivated fallow, and farmland （Triticum aestiuum L.） in order to obtain a better understanding of soil moisture balance principles and to improve vegetation restoration efficiency for ecological rebuilding on the plateau. Average runoff from cultivated fallow was very high, reaching 10.3% of the seasonal rainfall. Evapotranspiration under T. aestivurn was not significantly different from natural grasslands. Compared with natural grass, evapotranspiration was significantly greater （P 〈 0.05） in 2002 and there was an increase in soil moisture depleted in the 1-3 m soil under P. armeniaca, P. tabulaeformis and C. microphylla. During the two years of the study the average soil moisture （0-100 cm soil profile） of T. aestivurn was generally the highest, with P. armeniaca, P. tabulaeformis and C. rnicrophylla usually the lowest. Thus, according to the soil moisture balance principle for this area the planned reforestation project was not ecologically reasonable. Reducing human disturbance and restoration with grass could be more effective.     

Ephemeral gully erosion by preferential flow through a discontinuous soil-pipe

Subsurface flow through soil-pipes can contribute to ephemeral gully erosion but these soil-pipes are cut-off when tillage fills in the gully. The objective was to determine the effect of flow through discontinuous soil-pipes on ephemeral gully erosion. Experiments were conducted on 150 cm long by 100 cm wide soil beds with an artificial soil-pipe at the upper end that extended 50 cm into the soil immediately above a water-restricting horizon. The combination of rainfall with pipe flow produced extensive (63 kg) soil losses by mass wasting. The mode of mass wasting appeared to be sudden, cataclysmic pop-out failures. Total soil loss by sheet erosion with rainfall and pipe flow combined (13.6 kg) was four times higher than by rainfall alone (3.4 kg). Under rainfall with pipe flow, soil loss by mass wasting was nearly 20 times higher than sheet erosion from rainfall alone. Soil conservation practices that treat surface runoff process alone may be ineffective if subsurface flow is contributing.     

黄土高原水蚀风蚀交错带沟岸灌木林地土壤水分变化

选择黄土高原水蚀风蚀交错带典型切沟,采用人工取样和中子仪测定研究了柠条坡地不同坡位土壤水分变化,明确了切沟对沟岸柠条林地土壤水分的影响范围,建立了土壤储水量与距沟沿不同距离之间的关系。结果表明：在黄土高原雨季(7～10月),天然降水对柠条坡地下位的补给深度达到了220 cm,对坡地上位和中位的补给深度分别为180 cm和160 cm。在土壤剖面200 cm深度范围内,坡下位土壤水分含量始终高于坡上位和坡中位,200 cm深度以下,坡地上、中、下位土壤水分趋于一致。切沟对柠条林地土壤水分影响水平宽度达到3～4 m,垂直深度达到6 m以下。沟岸柠条坡地距沟沿不同距离土壤剖面储水量与沟沿距离间的关系可以用线性函数来表达。研究沟岸地距沟沿不同距离的土壤水分变化规律对沟岸地植被的恢复具有重要的科学意义。     

黄土丘陵沟壑区坡沟系统切沟侵蚀数值模拟

切沟侵蚀过程既是侵蚀输沙发生变化过程,也是其侵蚀地貌的发展演变过程,为了说明切沟形态随时空演化过程,应用质量守恒原理和理论分析方法,论述切沟侵蚀过程与形态发育模型实现的原理和过程,建立切沟侵蚀输沙微分方程、下切方程,并进行数值模拟.通过模拟计算,得到不同时刻和不同坡长下的切沟底部高程变化数据;经过与坡沟系统模型试验观测结果进行比较检验,沟深平均相对误差在15％以内,取得了较高的模拟精度.这表明建立的模型合理,模拟结果与实际切沟下切的动态变化过程相符,可以用于模拟切沟下切发育过程.     

黄土丘陵沟壑区细沟发育形态的变化及其与侵蚀产沙的关系

细沟发育及形态特征研究对理解坡面侵蚀过程和机理具有重要意义。然而,已有细沟侵蚀研究多基于室内模拟试验,无法反映野外真实细沟侵蚀规律。该研究以黄土丘陵沟壑区辛店沟流域为例,于野外自然坡面设置5个径流小区,结合放水冲刷试验（流量为25、40、55、70、85L/min）与地基三维激光扫描技术,研究细沟几何形态（长、断面宽、断面深）,衍生特征（细沟宽深比、细沟密度、细沟割裂度和细沟平均深度等）和分形维数、地貌信息熵、分叉比的变化过程,以及不同指标与侵蚀量、沉积量、产沙量间的关系。结果表明：1）随着冲刷时间增加,各流量梯度细沟断面宽度、断面深度、细沟平均深度和细沟割裂度大多呈递增趋势。而细沟宽深比与流量大小相关,低流量（25 L/min）下细沟发育主要呈“宽浅式”,较低流量（40 L/min）和高流量（85 L/min）下发育主要呈“窄深式”,中流量（55 L/min）和较高流量（70 L/min）细沟发育在“宽浅式”与“窄深式”间交替变化。2）随着冲刷时间增加,低流量下分形维数整体趋于平稳,其余流量波动较大;中流量下分叉比呈上升趋势,其余流量下均呈下降趋势;各流量梯度下地貌信息熵无明显变化规...     

切沟侵蚀监测与预报技术研究述评

切沟侵蚀作为一种常见的土壤侵蚀现象,不仅破坏土地资源,也是河流泥沙的主要来源之一;但是,由于切沟侵蚀机制复杂,研究手段欠缺,切沟侵蚀研究进展缓慢。切沟侵蚀监测技术是研究切沟不同发育阶段侵蚀速率和构建切沟预报模型的基础。近年来,高精度GPS、三维激光地形测量以及RS和GIS等切沟侵蚀监测技术取得了新进展,尤其是高分辨率遥感的应用为较大时空尺度的切沟侵蚀监测提供了可能性。世界范围的切沟侵蚀监测成果表明不同地区切沟侵蚀速率主要为0.16～15 m/a。切沟侵蚀预报技术进展缓慢,现阶段还没有广泛应用的切沟侵蚀预报模型。利用高分辨率航空和卫星影像及三维激光测量等新技术,开展较大尺度的切沟侵蚀监测是近期的研究热点和主要发展趋势,而从长远来看,发展切沟发育和侵蚀的经验和机制模型、进行不同时间尺度的切沟侵蚀预报是切沟研究领域的发展方向。     

基于双向地形阴影法的黄土侵蚀沟自动提取技术

沟蚀严重危害着土地资源和生态环境,研究高分辨率数字高程模型（Digital Elevation Model,DEM）的侵蚀沟自动提取技术进行侵蚀沟动态监测,以期望能替代目视解译提取。双向地形阴影法是一种兼顾提取精度和效率的侵蚀沟提取方法,但仅针对黄土台/塬地貌,在其他地貌下其提取结果会产生较多误提区和漏提区。为使其适应不同地貌,该研究以陕西吴堡县3.2 m DEM为试验数据,综合沟谷线缓冲区填充法、膨胀腐蚀法以及面积阈值法消除误提区和漏提区,并通过模块化编程及数据分块计算,实现侵蚀沟自动提取,最后在全县范围内均匀选取10个小流域为样本,使用0.65 m影像目视解译的结果进行精度验证。结果表明：1）实现了误提区和漏提区的自动消除,得到了吴堡县侵蚀沟分布图;2）在10个验证小流域中,该研究方法提取侵蚀沟的精度为81.1%～86.3%,平均精度为83.8%。该研究综合应用沟谷线缓冲区填充法、膨胀腐蚀法和面积阈值法消除误提区和漏提区,使该方法能适应非黄土台/塬地貌,并在此基础上研发了能实现大区域侵蚀沟提取的算法及软件。     

Estimating the rate and consequences of gully development,a case study of umbulo catchment in Southern Ethiopia

In southern Ethiopia wide and deep gullies are common features, significantly affecting farmers' livelihoods. Little action is being taken to address the problem despite farmers being knowledgeable about erosion and its control measures. A study was conduced to investigate the nature and rate of gully development in Umbulo catchment, southern Ethiopia, based on interviews with farmers and field measurements. The results indicated a rapid, down slope development of gullies over the last 30 years with average rate of soil loss from 11 to 30 t ha⁻¹ y⁻¹. The critical period of development of the gully system was estimated to be between 1974 and 1985, but since then the gully system has enlarged both in depth and width. Wide channels with deep, nearly vertical walls are typical. The trigger for gully initiation is believed to have been human, but the soil properties may have played an important role. Under the current situation agricultural production is unsustainable unless the gullies are controlled using integrated measures at the catchment scale. Copyright © 2008 John Wiley & Sons, Ltd.     

Investigating the spatial distribution of soil erosion and deposition in a small catchment on the Loess Plateau of China, using Cs

An understanding of the spatial distribution of soil erosion and deposition in a catchment is important for designing soil and water conservation measures. Traditional monitoring techniques provide limited information on the spatial patterns of erosion and deposition. The fallout radionuclide ¹³⁷Cs was used to document rates and patterns of soil redistribution within a small (0.17 km²) gully catchment located near An'sai in Shaanxi Province, representative of the Loess Plateau of China. The local reference inventory was estimated to be 2266 Bq m⁻² and the ¹³⁷Cs inventories of 198 soil cores collected from the catchment, ranged from 0 to 3849 Bq m⁻². The coefficient of variation of the inventories of the individual cores was 0.85, reflecting the complex pattern of ¹³⁷Cs redistribution by soil erosion and deposition. Estimates of erosion rates derived from ¹³⁷Cs measurement ranged from less than 25 to 150 Mg ha⁻¹ year⁻¹, with about 70% of the net soil loss from the catchment coming from the gully area. The ¹³⁷Cs technique was shown to provide an effective means of documenting the spatial distribution of soil erosion and deposition within the small catchment.     

Time and scale of gully erosion in the Jedliczny Dol gully system, south-east Poland

Key catchments of the Roztocze loess area in south-east Poland have a great potential of revealing the history of long-term soil erosion and changes in land use. The knowledge of how and when soil erosion took place in the past helps one understand the impact of land use changes on the landscapes [Bork, H.-R., 1989. Soil erosion during the past Millennium in Central Europe and its significance within the geomorphodynamics of the Holocene. Catena 15, 121–131]. The Jedliczny Dol gully system near the town Zwierzyniec in south-east Poland was investigated by using detailed field stratigraphy and radiocarbon dating of charcoal and wood.In connection with new settlements which were established between the 14th and 16th centuries, arable land was cultivated and forests were used much more intensively. As a consequence, the loess soils were strongly eroded during heavy rainfalls. Up to 4 m of colluvial sediments were deposited in the gully system during the 15th and/or 16th centuries. The thickness of the colluvial sediments indicate severe erosion which might be related to excessive timber exploitation for the local glass and iron production. With the foundation of the so-called Ordinariat Zamoyski at the end of the 16th century, some parts of the area were presumably reforested. High pressure on the land at the beginning of the 19th century enabled a second main phase of gulling before 1900.Since 1890 at the latest, almost the whole catchment is used as a forest, however, concentrated runoff on compacted forest roads can still be high after heavy rainfalls.In loess areas soil erosion caused by intensive land use, triggered by heavy rainfalls, can change the landscape drastically. These changes will continue to influence how catchments react, even if land use gets less intensive again. This knowledge should be considered regarding future, sustainable land use and recent changes in land use in the south-eastern Polish loess regions.