The efficiency of different mulch types and dose applications on runoff, soil, and nutrient losses under simulated rainfall

Mulching is one of the best management practices used in soil and water conservation studies. The aim of this study is to determine the effects of different mulch types and doses on runoff coefficient (Rc), soil loss (Er), sediment concentration (Sc), time to ponding (tp), runoff generation time (tr), percolated (pw) and retained (rw) water and total losses of nitrate-nitrogen (NO3-), ammonium-nitrogen (NH4+), total nitrogen (TN), phosphate-phosphorus (PO43-), and total organic carbon (TOC) under simulated rainfall in the laboratory. Three different mulch materials (dry weed, peanut hay, and wheat straw) were applied at four different doses (0, 2, 4, and 6 t/ha) on the experimental plots. A simulated rainfall intensity of 97 mm/s was applied for an hour. All mulch types and doses reduced Rc, and the most effective reduction was found in 2 t/ha dry weed mulch applied plots. The most effective application for reducing soil loss was 6 t/ha peanut hay mulch. The most effective application for delaying the ponding time and runoff generation time was the 4 t/ha application of wheat straw mulch. The highest pw and rw were found in 6 t/ha and 4 t/ha doses of dry weed mulch applications, respectively. The most effective application for reducing NH4+ losses was found in 4 t/ha wheat straw application plots. The most effective mulch type and dose for reducing NO3- loss was 6 t/ha of dry weed mulch. The lowest TN loss was found in the plots where 6 t/ha of peanut hay mulch was applied. In terms of PO43- losses, the lowest loss was in 6 t/ha of dry weed mulch plots. The lowest TOC loss was at 4 t/ha of straw mulch applications. Mulching can be a good natural-based solution for reducing soil, water, and nutrient loss. However, different mulch types and doses should be tested for different environmental conditions to determine the most cost-effective mulch type and dose.