METHODS FOR ASSESMENT OF SOIL EROSION PUBLISHEDGheorghe ROGOBETE, Adia GROZAV
Excessive erosion can threaten the production of agricultural and forest products. Erosion may also have a negative impact of water streams and lakes. The main objectives of the study were to develop the methods for assessment of soil erosion, with an application in three territories from catchment area Bârzava. The first method is based on the detachment model and estimates the soil erosion with Trott’s equation, modified by Rogobete and Grozav. The new equation was obtained using a soil pan in order to study the effect of row-sideslope shape, rain energy, and rain intensity on interrill runoff and erosion. Left plot has uniform 20 % slope; right plot has curved complex-shaped surface. Soil detachment represents a major improvement in erosion modeling compared with that used in the Universal Soil Loss equation. A more rigorous framework is needed for studying and making further advances in predicting the detachment process. The theoretical framework is presented in a generalized form where assumptions can be challenged and the relationship modified and improved by future research. The amount of sediment production were calculated for 6 soil profiles, based on particle size analyses, humus content and Kaolinite and Smectite content. The greatest values were of Vertic Luvisols from Berzovia (18,53 t/ha) and Vertic Planosols (11,88 t/ha). The smallest values of sediment production was of Gleyic Fluvisols (5,05 t/ha) and of Eutric Gleysols (5,46 t/ha), soils which have had a great quantity of humus. Soil profile reconstitution was the second method used in order to establish the soil erosion phase. The values of the depth of horizons which were eroded varies between 2 cm and 45 cm with an amount of soil lost between 238 t/ha to 6435 t/ha. Maximum value was at Luvisols –eroded phase. Conservation measures in order to reduce soil erosion include contouring, strip cropping, conservation tillage, terraces, buffer strips, and use of polyacrylamide. One of the most effective means of reducing erosion is to maintain a vegetative or residue cover on the soil surface.
erosion; predict; equation; soil; reconstitution