不同膜上遮挡措施对旱地玉米土壤理化性状及产量的影响

Effects of different cooling methods on maize soil physical and chemical properties and yield in dryland

Aiming at the phenomenon of premature senescence of plants under long-term maize plastic film mulching in rainfed and arid regions in Northwest China, adding cooling measures on mulched maize were taken to study the effects of soil temperature change on maize yield formation and analysis the changes of soil physical and chemical properties in topsoil of maize from the perspective of never changing the water conserving function of plastic film, which would provide the theoretical reference for the analysis of the early senescence in the later growth stage of ordinary plastic film maize. This experiment design using Shaandan 609 (SD 609) as tested materials, based on a 2-year field experiment, compared with the effects of three modes, ordinary plastic film mulch + black sunshade net (A), ordinary plastic film mulch + straw (B) and ordinary plastic film mulch (C) on soil temperature, soil nutrients, dry matter mass accumulation yield and water and fertilizer use efficiency in yield. The results were as follows: (1) Adding coverings on plastic film mulching (black sunshade net, straw) can effectively decrease the soil temperature and compactness, especially early stage of maize growth. (2) Compared with the control treatment C, cooling treatment A and treatment B significantly increased the content of organic matter, total nitrogen and total potassium in the later stage of maize growth, and the average partial fertilizer productivity increased by 7.24% and 6.97%, respectively. (3) Cooling treatments can delay the attenuation of green leaf area in the later stage of maize growth, improve the accumulation rate of dry matter and increase the kernel weight of maize. Compared with treatment C, the 2-year average maize yields of cooling treatment A and treatment B were increased by 6.39% and 5.93% and the average water use efficiency by 8.17% and 7.67%, respectively. In rainfed and arid regions in Northwest China, properly reducing the temperature under the film of mulched maize are helpful to improve soil physical and chemical properties, promote the accumulation of dry matter and the formation of yield and improve the high utilization efficiency of fertilizer and water.