Effects of straw mulching on soil temperature, evaporation and yield of winter wheat: field experiments on the North China Plain

Abstract

Straw mulching is an effective measure to conserve soil moisture. However, the existence of straw on the soil surface also affects soil temperature, which in turn influences crop growth, especially of winter crops. Five-year field experiments (2000)(2001)(2002)(2003)(2004)(2005) investigated the effects of straw mulching and straw mass on soil temperature, soil evaporation, crop growth and development, yield and water use efficiency (WUE) of winter wheat (Triticum aestivum L.) at Luancheng Station on the North China Plain. Soil is a moderately well-drained loamy soil with a deep profile at the station. Two quantities of mulch were used: 3000 kg ha 21 [less mulching (LM)] and 6000 kg ha 21 [more mulching (MM)], representing half and all of the straw from the previous crop (maize). In the control (CK), the full quantity of mulch was ploughed into the top 20 cm of soil. The results showed that the existence of straw on the soil surface reduced the maximum, but increased the minimum diurnal soil temperature. When soil temperature was decreasing (from November to early February the next year), soil temperature (0-10 cm) under straw mulching was on average 0.3°C higher for LM and 0.58°C higher for MM than that without mulching (CK). During the period when soil temperature increased (from February to early April, the recovery and jointing stages of winter wheat), average daily soil temperature of 0-10 cm was 0.42°C lower for LM and 0.65°C lower for MM than that of CK. With the increase in leaf area index, the effect of mulching on soil temperature gradually disappeared. The lower soil temperature under mulch in spring delayed the development of winter wheat up to 7 days, which on average reduced the final grain yield by 5% for LM and 7% for MM compared with CK over the five seasons. Mulch reduced soil evaporation by 21% under LM and 40% under MM compared with CK, based on daily measuring of microlysimeters. However, because yield was reduced, the overall WUE was not improved by mulch.

Combined Effects of Mulch and Tillage on Soil Hydrothermal Conditions under Drip Irrigation in Hetao Irrigation District, China

“…At this stage, RFM showed a greater water storage capacity than RPM. This implies that ridge tillage could be beneficial to increase soil water storage, to a certain extent through increasing rainwater retention and promoting infiltration, however, some soil water evaporated rapidly from un-mulched furrows under intense solar radiation, which is consistent with the results of previous research [37,38]. In contrast, during heading and maturing stage, soil water storage decreased in 0-70-cm layers of all treatments, especially in the 0-40-cm layer of RFM and FFM.…”

Can ridge-furrow plastic mulching replace irrigation in dryland wheat and maize cropping systems?

“…This effect of soil temperature, however, was less obvious in irrigated crops because farmers in northern China traditionally followed a late sowing procedure (Zhang et al, 1998). The effect of soil temperature on crop performance would decrease rapidly with increasing leaf area index since soil temperature only controlled the rate of crop development when the plant meristem was within the soil (Chen et al, 2007).…”

Evaporação da água na superfície do solo em sistemas de plantio direto e preparo convencional

“…A palha modifica a perda de água na superfície do solo por alterar a ação dos elementos meteorológicos que compõem a demanda evaporativa da atmosfera (Aydin et al, 2005;Chen et al, 2007), e também por formar uma espécie de camada isolante ao fluxo hídrico, por causa do ar que permanece relativamente parado dentro da camada de palha (Lemon, 1956). No que se refere aos fatores de solo que interferem na evaporação, a estrutura, a densidade, a porosidade e a condutividade hidráulica não saturada são os mais importantes (Yang & Yanful, 2002), e afetam o teor de umidade e o fluxo de água no perfil do solo (Lemon, 1956;Yang & Yanful, 2002).…”