枣园间作棉花、苜蓿土壤呼吸差异及效益分析

Soil respiration difference and benefit analysis of intercropping cotton and alfalfa in jujube orchard

不同种植模式会对土壤温室气体排放、作物产量和经济效益产生不同的影响。本试验采用静态箱法结合气相色谱仪对枣棉间作、棉花单作、枣苜间作和苜蓿单作4种不同种植模式下土壤温室气体的排放进行测定,并对其产量和经济效益进行计算和综合分析,以确定综合收益最高的种植模式。结果表明,枣棉间作与棉花单作相比,CO_(2)排放通量减少了15.78%,N_(2)O排放通量减少了76.40%。枣苜间作与苜蓿单作相比CO_(2)排放通量减少了1.06%,N_(2)O排放通量减少了57.89%。枣棉间作与枣苜间作相比CO_(2)排放通量增加了206.42%,N_(2)O排放通量增加了375.00%。棉花单作比枣棉间作的产量增加了40.90%。在总共收割的两茬苜蓿中,第一茬的苜蓿单作比枣苜间作产量增加了93.24%,第二茬苜蓿单作比枣苜间作产量增加了27.31%。枣棉间作比棉花单作净收入增加了24.00%。两茬苜蓿间作比单作的净收入增加了35.00%。间作模式有利于土壤CO_(2)、N_(2)O的减排。综合温室气体排放通量、产量与经济效益因素,在本试验区域综合收益较高的种植模式依次为枣苜间作和枣棉间作。

Different planting patterns have different effects on soil greenhouse gas emissions,crop yield and economic benefits.In this experiment,static box method combined with gas chromatograph were used to measure the greenhouse gas emission of soil under four different planting patterns:jujube-cotton intercropping,cotton monocropping,jujube-alfalfa intercropping and alfalfa monocropping,and the yield and economic benefit were calculated and comprehensively analyzed to determine the planting pattern with the highest comprehensive income.The results showed that compared with cotton monoculture,jujube-cotton intercropping reduced CO_(2) emission flux by 15.78%and N_(2)O emission flux by 76.40%.Compared with alfalfa monoculture,jujube-alfalfa intercropping decreased CO_(2) emission flux by 1.06%and N_(2)O emission flux by 57.89%.Compared with jujube-alfalfa intercropping,jujubecotton intercropping increased CO_(2) emission flux by 206.42%and N_(2)O emission flux by 375.00%.The yield of cotton monoculture increased by 40.90%compared with jujube cotton intercropping.Among the two alfalfa harvests,the yield of the first alfalfa single cropping increased by 93.24%compared with the jujube-alfalfa intercropping.The yield of alfalfa monoculture in the second crop increased by 27.31%compared with jujube-alfalfa intercropping.The net income of jujube-cotton intercropping increased by 24.00%compared with cotton monoculture.The net income of intercropping two alfalfa crops increased by 35.00%compared with single cropping.Intercropping mode is beneficial to soil CO_(2) and N_(2)O emission reduction.Considering greenhouse gas emission flux,yield and economic benefits,jujube-alfalfa intercropping and jujube-cotton intercropping are the planting patterns with higher comprehensive in come in this experimental area.