水保所知识产出(1956---)知识库

BACKGROUND:Plastic filmmulchis widelyusedtoimprove cropyield and wateruseefficiency (WUE,yield per unit evapotrans-
piration) in semi-arid regions. It is commonly applied as partial-film mulch (PM: at least 50% soil cover) or full-film mulch (FM:
complete soil cover). The PM has lower economic and environmental cost; hence it would be a superior technology provided it
delivers similar gains in yield and WUE in relation to FM.
RESULTS:Tosolvecontradictory resultsfromindividual studies,wecomparedFMandPMinameta-analysisof100studieswith
1881 comparisons (685 for wheat; 1196 for maize). Compared with bare ground, FM and PM both increased yield of wheat (20–
26%) and maize (37–52%), and WUE of wheat (16–20%) and maize (38–48%), with statistically undistinguishable differences
between PM and FM. The increases in crop yield and WUE were stronger at elevation > 1000 m, with annual precipita-
tion<400 mm, and on loess soil, especially for maize.
CONCLUSIONS: We concluded that partial-film mulch could replace full-film mulch to return similar yield and WUE improve-
ment, with reduced cost and environmental pollution.