Straw mulch effect on soil and water losses in different growth phases of Maize sown on Stagnosols in Croatia

Abstract

Soil and water losses due to traditional intensive types of agricultural management are high and non-sustainable in Croatian croplands. In order to mitigate the accelerated land degradation, we study different cropland soil management to obtain possible sustainable agrotechnical practices. A rainfall simulation experiment was conducted at 60 mm h–1 over 30 min on 10 paired plots (0.785 m2), bare and straw covered (2 t ha-1). The experiment was carried out in maize cultivation (Blagorodovac, Croatia) established on Stagnosols on slopes. Measurements were conducted during April (bare soil, after seeding), May (five leaves stage), and June (intensive vegetative growth) making 60 rainfall simulations in total. Straw reduced soil and water losses importantly. The highest water, sediment loss, and sediment concentrations were identified in tillage plots during May. Straw addition resulted in delayed ponding (for 7%, 63 and 50% during April, May and June, respectively) and runoff generation (for 37%, 32 and 18% during April, May and June, respectively). Compared to the straw mulched plot, tillage and bare soil increase water losses by 349%. Maize development reduced the differences between bare and straw mulched plots. During May and June bare plots increase water losses by 92% and 95%, respectively. The straw mulch reduced raindrop kinetic energy and sediment detachment from 9, 6 and 5 magnitude orders at April, May and June. Overall, the straw mulch was revealed to be a highly efficient nature-based solution for soil conservation and maize cultivation protection.