Concept of a single device for simultaneous simulation of wind and water erosion in the field

Soil degradation and desertification are often caused by wind and water erosion. For many years researchers have been studying both processes separately. Recent field researches in semi-arid areas have shown that measuring both processes together is necessary for future quantification and prediction of soil desertification. Unfortunately no applicable field equipment has been developed that is capable of measuring both processes at once. The main objective of this study is to investigate both processes simultaneously with a single device operational in the field. Firstly a small portable wind tunnel (3 m long, 0.7 m high, and 0.7 m wide) with a plot size of 2 m² was constructed and calibrated. Secondly a rainfall simulator with four pressure nozzles positioned at 0.35 m, 1.1 m, 1.85 m and 2.6 m in flow direction of the tunnel will be incorporated to generate a rainfall intensity of 40 to 100 mmh-1. A gutter system is used to catch the runoff from the plot. Attached to it are two wedge-shaped sediment traps and a beam with four Modified Wilson and Cook (MWAC) samplers to catch the airborne material. After build up at the test site multiple plot characteristics, for example surface roughness and vegetation cover, will be registered. Test duration will be 30 min with measurement intervals of 5 min duration for surface runoff. MWAC and wedge samplers will be cleaned after each test run. By means of this combined device we expect to obtain quantitative information regarding the relative impact of wind and water erosion even in remote areas also taking into account different soil surfaces as well as varying soil treatments.