Water erosion is considered one of the most serious degradation processes on agricultural land. If areas at risk are not managed properly, soil is carried away with every major rainfall. The eroded material also contains large amounts of nutrients, which are subsequently missing, and the soil becomes less fertile. The missing nutrients have to be replenished at a high cost. Eroded soil and leached nutrients also cause a number of problems outside the field, e.g., contaminating watercourses and reservoirs where eutrophication (nutrient enrichment) occurs, silting up roads and human settlements.
You are in a soil block where we have created three experimental plots to test the erosion control efficiency and the ability to infiltrate surface water into the soil when growing sorghum and winter rape. We tested the following establishment technologies:
- conventional ploughing
- strip-till
- sowing in narrow rows
- deep and shallow pre-sowing cultivation.
Strip-till technology has clearly the best anti-erosion results in sorghum cultivation. In winter rape, there was less soil loss with deep and shallow pre-sowing cultivation. Although conventional ploughing is often recommended, we measured worse results for water erosion parameters compared to other establishment methods.
Our monitoring system for measuring water erosion follows the testing of agronomic measures for each crop being tested. In the lower part of the experimental plots, there are silt-fences of 100 m length that direct surface runoff to sedimentation pits and to a Parshall flume with a level gauge. A logging unit there records the flow and sends the data to a logging server via a GSM module. This whole system allows us to measure the volume of 'lost' soil.
