地膜覆盖条件下黄土高原玉米产量及水分利用效应分析

Effects of Plastic Film Mulching on Yield and Water Use of Maize in the Loess Plateau

【目的】综合评价地膜覆盖玉米的产量以及水分利用效应,为黄土高原地区玉米生产合理利用地膜覆盖技术提供指导。【方法】本文在中国知网(CNKI),Web of Science与EI Compondex文献数据库,收集了从2000—2017年间已发表的黄土高原地膜覆盖玉米产量及水分利用文章数据,综合分析了地膜覆盖对玉米产量、水分利用及水分利用效率的影响。【结果】黄土高原半膜覆盖平均产量为9348 kg·hm^-2,较对照产量7059 kg·hm^-2增产33%,全膜覆盖平均产量为9191 kg·hm^-2,较对照产量5910 kg·hm^-2增产56%,半膜覆盖或者全膜覆盖均显著提高了玉米产量,但是全膜覆盖和半膜覆盖之间玉米产量相近,没有显著差异。另外,半膜覆盖海拔高度超过630 m时或全膜覆盖海拔高度超过900 m时,玉米增产率随海拔高度的增加而呈增加的趋势,可能与覆膜提高土壤温度有关。半膜覆盖平均蒸散量为385 mm,较对照蒸散量389 mm减少1.0%,全膜覆盖平均蒸散量为366 mm,较对照蒸散量357 mm增加2.8%,半膜覆盖玉米蒸散量较不覆膜有所减少,但是全膜覆盖显著增加了玉米蒸散量,不过2种覆膜措施的蒸散量之间差异不显著。半膜覆盖平均水分利用效率为17.3 kg·hm^-2·mm^-1,较对照水分利用效率13.2 kg·hm^-2·mm^-1增加31%,全膜覆盖平均水分利用效率为17.5 kg·hm^-2·mm^-1,较对照水分利用效率11.7 kg·hm^-2·mm^-1增加50%,半膜覆盖与全膜覆盖均显著提高了玉米水分利用效率,但是全膜覆盖和半膜覆盖之间玉米水分利用效率相似,没有显著差异。覆膜显著增加玉米产量及水分利用效率与其降低土壤无效蒸发量(57 mm),提高玉米潜在的蒸腾效率有关(11.2 kg·hm^-2·mm^-1)。【结论】在区域尺度上半膜覆盖与全膜覆盖对玉米产量、蒸散量及水分利用效率具有等效性,考虑到地膜的环境污染与经济成本等因素,推荐黄土高原玉米栽培选用半膜覆盖。

【Objective】Present study comprehensively evaluated effectiveness of the yield and water use under plastic film mulching for maize production,so as to provide a theoretical basis for the rational utilization of plastic film mulching in the Loess Plateau area.【Method】The published data about plastic film mulching of maize were collected in the Loess Plateau from 2000 to 2017,using CNKI,Web of Science and EI Compondex,to analyze the effects of plastic film mulching on maize yield,water use and water use efficiency.【Result】The results showed that,the average yield of 50%film mulching was 9348 kg·hm^-2,which was 33%higher than the control of 7059 kg·hm^-2;The average yield of 100%film mulching was 9191 kg·hm^-2,which was 56%higher than the control of 5910 kg·hm^-2;Compared with no film mulching,both 100%film mulching and 50%film mulching significantly increased the yield of maize.However,the yield of maize under 100%film mulching and 50%film mulching was similar.In addition,the increase of maize yield was significantly and positively related with the increase of altitude,which was higher than 900 m under 100%film mulching and 627 m under 50%film mulching,respectively.This was possibly ascribed to the increase of soil temperature under film mulch.The average evapotranspiration(ET)of 50%film mulching was 385 mm,which was 1%lower than the control of 389 mm;The average ET of 100%film mulching was 366 mm,which was 2.5%higher than the control of 357 mm,the ET under 50%film mulching and the control was similar,but 100%film mulching significantly increased evapotranspiration relative to the control,while there was no significant difference between the two mulching treatments.The average water use efficiency(WUE)of 50%film mulching was 17.3 kg·hm^-2·mm^-1,which was 31%higher than the control of 13.2 kg·hm^-2·mm^-1;The average WUE of 100%film mulching was 17.5 kg·hm^-2·mm^-1,which was 50%higher than the control of 11.7 kg·hm^-2·mm^-1;Compared with the control,both 100%film mulching and 50%film mulching significantly increased the WUE of maize.However,the WUE of maize under 100%film mulching and 50%film mulching was similar.The significant increase of maize yield and WUE by film mulching was related to the decrease of soil evaporation by 57 mm and the increase of potential transpiration efficiency by 11.2 kg·hm^-2·mm^-1.【Conclusion】At the regional scale,50%film mulching and 100%film mulching had equivalent effects on maize yield,evapotranspiration and water use efficiency.Considering the environmental pollution and economic cost caused by film mulching,50%film mulching was recommended for maize cultivation in the Loess Plateau.