黄土高原南部地膜覆盖小麦产量及水分利用效应分析

综合评价地膜覆盖的产量以及水分利用效应,有利于干旱半干旱地区合理利用地膜覆盖技术。本研究收集1997—2017年间黄土高原南部地膜覆盖小麦产量及水分利用已发表文章的数据,分析地膜覆盖对小麦产量、水分利用及水分利用效率的影响,同时利用边界函数方法求得区域小麦潜在蒸腾效率。研究表明,与不覆膜相比,半膜覆盖平均增产率为29%(-21%～97%),全膜覆盖平均增产率为34%(-14%～153%)。半膜与全膜覆盖间小麦产量相似,无显著差异。半膜与全膜覆盖小麦蒸散量较不覆膜显著增加,但两种覆膜措施蒸散量差异不显著。黄土高原南部覆膜条件下小麦潜在蒸腾效率为22.5 kg·hm^-2·mm^-1,最低土壤蒸发量为35 mm;不覆膜小麦潜在蒸腾效率为18.5 kg·hm^-2·mm^-1,最低土壤蒸发量为54.4 mm。半膜覆盖与全膜覆盖较不覆膜显著增加了小麦水分利用效率,半膜覆盖水分利用效率平均增加24%(-21%～84%),全膜覆盖平均增加率为31%(-15%～152%)。半膜与全膜覆盖间水分利用效率也相似。覆膜显著增加...

Effect of Plastic Film Mulching on Wheat Yield and Water Use Efficiency in South of Loess Plateau

Comprehensive evaluation of the yield performance and water use efficiency under plastic film mulching is of great significance for rational use of this technique in arid and semi-arid areas. We evaluated the effect of plastic film mulching on wheat yield and water use efficiency in the Loess Plateau by collecting published data from 1997 to 2017. We also estimated seasonal potential transpiration efficiency (PTE) by employing boundary function method. The results showed that wheat yield increased averagely by 29% (-21% to 97%),under 50% film mulching and the yield increased averagely by 34% (-14% and 153%) under 100% film mulching,respectively,compared with conventional tillage with non-film mulching.The evapotranspiration was significantly higher than non-mulching control under plastic film mulching.Compared with non-mulching,50% and 100% film mulching increased the water use efficiency by -21%-84% with a mean value of 24% and -15%-152% with a mean of 31%,respectively. However,no difference were observed between these two mulching approaches in crop yield performance,evapotranspiration and water use efficiency. The potential transpiration efficiency for wheat was 22.5 kg·hm^-2·mm^-1 in the tested region with a minimum soil evaporation of 35 mm under plastic film mulching,but PTE was 18.5 kg·hm^-2·mm^-1 with a minimum soil evaporation of 54.4 mm under non-plastic film mulching conditions. The increases in yield and water use efficiency under film mulching could be mainly related to the reduced soil evaporation by the treatments and improved PTE. The most important finding was that the effectiveness of 50% and 100% film mulching was equivalent. Thus,50% film mulching should be recommended for wheat production in the Loess Plateau because of the less environmental pollution and economic cost.