Soil protecting effect of the surface cover in extreme summer periods

Abstract

It was to investigate the effects of mulch cover and stubble tillage on soil water content and to assess grounds of recommendations in stubble management in an extreme dry period. Tests were carried out in undisturbed (U) soil, after shallow (S) and deep (D) tillage, soil with (UCO, SCO, DCO) and without surface cover (UCL, SCL, DCL) and after conventional stubble treatment (STR). Effective moisture conservation (8–11%) was observed in undisturbed soil under 55% and 65% cover ratios. The water content in the top 0.65 m soil layer increased significantly (LSD, P < 0.05) between the different stubble variants, the following order was established on day 85: DCL < STR < SCL < UCL < DCO < SCO < UCO. The conventional stubble management cannot be applied in soils after shallow (STR) or deep tillage (DCL) in a dry season, when the loss of water is even statistically proven. Leaving the soil without a cover (UCL) or having it with insufficient cover (< 15%) entails risks in soils. Increasing the soil cover ratio (from 5% to 75%) had a 1.3–2.3 times stronger impact on crumb forming than did the moisture recorded in the various seasons.