The largest currently compiled database of plot runoff and soil loss data in Europe and the Mediterranean was analysed to investigate effects of land use on annual soil loss (SL), annual runoff (R) and annual runoff coefficient (RC). This database comprises 227 plot-measuring sites in Europe and the Mediterranean, with SL for 1056 plots (PL) representing 7024 plot-years (PY) and R for 804 PL representing 5327 PY. Despite large data variability, continental-wide trends are observed. Construction sites have the highest mean annual RC (57%) and SL (325 Mg.ha -1 .yr -1 ). Bare soil, vineyards and tree crops have high mean annual RC (5-10%) and SL (10-20 Mg.ha -1 .yr -1 ). Cropland and fallow show similar mean annual RC (8.0 and 7.3%), but lower SL (6.5 and 5.8 Mg.ha -1 .yr -1 ). Plots with (semi-)natural vegetation cover show lowest mean annual RC (<5%) and SL (<1 Mg.ha -1 .yr -1 ). Plot length and slope gradient correlations with R and SL depend on land-use type and are not concurrent for R and SL. Most land-use types show positive correlations between annual R and SL. Plots in cold climates have higher annual RC than plots in temperate and pan-Mediterranean climates. Annual SL in the pan-Mediterranean is less than in temperate zones, due to stony or clayey soils having a low erodibility. Annual RC in the pan-Mediterranean was higher than in temperate zones. Annual R increases strongly with increasing annual precipitation (P) above 500 mm.yr -1 , while annual SL was found to stabilize at P > 500 mm.yr -1 . For shrubland, annual SL was found to decrease for P > 250-500 mm.yr -1 , which is attributed to

Purpose: This study aims to understand better the relationship between measured soil loss rates due to sheet and rill erosion (SL), predicted SL rates and measured catchment sediment yields (SY) in Europe.2 Materials and methods: Analyses were based on a recently established database of measured annual SY for 1794 catchments, a database of 777 annual SL rates measured on runoff plots, and two recent maps of predicted sheet and rill erosion rates in Europe (i.e. one based on empirical extrapolations of measured SL data, and one based on the PESERA model). To identify regional trends, all data were grouped into eight climatic zones.Results and discussion: Measured SL rates are generally a factor of five to 10 times larger than predicted SL rates and are strongly biased towards erosion-prone situations in terms of land use. Also measured SY are generally higher than predicted SL rates, especially in the Mediterranean and Alpine regions where SY is generally 10 times higher than predicted SL rates. This illustrates the importance of other erosion processes contributing to SY. Regional differences in the importance of these processes and their implications are discussed. Conclusions:This study confirms previous findings indicating the relatively low sheet and rill erosion rates compared to SY in the Mediterranean region, and illustrates the importance of other erosion processes contributing to SY in most regions of Europe. This indicates that hillslope erosion rates cannot be used directly to estimate SY, and consequently soil conservation programmes should focus more on the dominant erosion processes in each catchment.

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Field and laboratory studies indicate that utilisation of biological geotextiles constructed from palm-leaves and other selected organic materials are an effective, sustainable and economically viable soil conservation technique. The three-year plus

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It is essential that we can rapidly characterize soil erosion severity. This paper describes a field methodology to classify soil erosion severity on Dystric Albeluvisols in Lithuania. The goal was to assess cumulative soil loss due to the combined action of accelerated and natural soil erosion. Evaluation of soil erosion severity helps us understand which segments of the landscape are susceptible to erosion and therefore require soil conservation. Factors considered in evaluating soil erosion severity included the existing genetic soil horizons remaining after soil erosion processes, the estimated thickness of lost soil, and slope inclination. The estimated depth of soil loss due to the combined action of natural (geological) and accelerated soil erosion was 0.1–0.8 m on the undulating hilly topography of the Zemaiciai Uplands of Western Lithuania. Erosion rates increased with slope steepness. Soil erosion changed soil physical and chemical properties. Therefore, natural soil fertility, as indicated by spring barley yields, decreased 22, 40 and 62% on slopes of 2–5° (3.5–8.3%), 5-10° (8.3–17.7%) and 10–15° (17.7–26.3%), respectively, compared with flat land. Crop yield was strongly negatively correlated (R2 = 0.79, P < 0.001, n = 138) with erosion severity. Due to pedological translocation, non-eroded Dystric Albeluvisols had relatively little clay and silt in eluvial (E) soil horizons, with their relative accumulation in illuvial (Bt) horizons . Thus, severely eroded soils had argillaceous top soils, due to exhumation of Bt horizons. The suggested classification system enables rapid assessment of past soil erosion severity and may have broader applicability in areas of Podzolic soils. Key words: Dystric Albeluvisols, soil erosion severity, slope steepness, soil properties, pedology

Preliminary investigations suggest biological geotextiles could be an effective and inexpensive soil conservation method, with enormous global potential. However, limited quantitative data are available on the erosion-reducing effects of biological geotextiles. Therefore, the objective is to evaluate the effectiveness of biological geotextiles in reducing runoff and soil loss under controlled laboratory conditions and under field conditions reflecting continental, temperate and tropical environments. In laboratory experiments, interrill runoff, interrill erosion and concentrated flow erosion were simulated using various rainfall intensities, flow shear stresses and slope gradients. Field plot data on the effects of biological geotextiles on sheet and rill erosion were collected in several countries (UK, Hungary, Lithuania, South Africa, Brazil, China and Thailand) under natural rainfall. Overall, based on the field plot data, the tested biological geotextiles reduce runoff depth and soil loss rates on average by 46 per cent and 79 per cent, respectively, compared to the values for bare soil. For the field and laboratory data of all tested geotextiles combined, no significant difference in relative runoff depth between field measurements and interrill laboratory experiments is observed. However, relative soil loss rate for the concentrated flow laboratory experiments are significantly higher compared to the interrill laboratory experiments and the field plot measurements. Although this study points to some shortcomings of conducting laboratory experiments to represent true field conditions, it can be concluded that the range and the mean relative runoff depth and soil loss rate as observed with the field measurements is similar to those as observed with the interrill laboratory experiments.

Jankauskas, B., Jankauskiene, G. and Fullen, M. A. 2004. Erosion-preventive crop rotations and water erosion rates on undulating slopes in Lithuania. Can. J. Soil Sci. 84: 177-186. A combination of perennial grass species and selected crop rotations can help prevent soil erosion in upland regions and minimize the risk of soil erosion and associated water pollution (to both terrestrial and aquatic ecosystems). Research data were obtained on sandy loam Eutric Albeluvisols at the Kaltinenai Research Station of the Lithuanian Institute of Agriculture on the undulating hilly topography of the Zemaiciai Uplands of Western Lithuania. The aim was to identify crops and crop rotations that would minimize soil erosion. Measured water erosion rates over 18 yr of field experiments were: 3.2-8.6 m 3 ha -1 yr -1 under winter rye, 9.0-27.1 m 3 ha -1 yr -1 under spring barley and 24.2-87.1 m 3 ha -1 yr -1 under potatoes. Perennial grasses completely prevented water erosion, while the erosion-preventive grass-grain crop rotations (>50% grass) decreased soil losses on arable slopes of 2-5°, 5-10°and 10-14°by 75-80%. The grain-grass crop rotation (<50% grass) decreased rates by 23-24% compared to the field crop rotation. The main attributes of the proposed soil conservation systems were the careful selection of optimum erosion-preventive ecosystems (sod-forming perennial grasses or erosion-preventive crop rotations) with high erosion-resisting capabilities. These selected systems varied in response to slope gradient and thus assist erosion control and ecological stability of the undulating topography of Lithuania. These results may have wider applicability on the undulating landscapes of the temperate agricultural zone.