紫花苜蓿/豆科牧草间作的生态效益分析

The Ecological Benefit Analysis on the Alfalfa/Legume Intercropping

为探究我国半干旱区紫花苜蓿(Medicago sativa)/豆科牧草适宜间作模式,本研究采用完全随机设计,以紫花苜蓿单作为对照,研究紫花苜蓿/3种豆科牧草(毛苕子(Vicia villosa)、箭筈豌豆(Vicia sativa)和豌豆(Pisum sativum))间作对土壤水分、杂草、捕食性节肢动物、饲草产量、水分利用效率和食物当量的影响。与紫花苜蓿单作相比,紫花苜蓿/毛苕子、紫花苜蓿/箭筈豌豆和紫花苜蓿/豌豆间作的紫花苜蓿全生育期干草产量分别提高30.2%,45.2%和61.3%;水分利用效率分别提高6.1,8.8和12.1 kg·hm^(-2)·mm^(-1),食物当量分别提高26.74%,19.96%和53.28%。紫花苜蓿/豆科牧草间作显著降低土壤贮水量(P<0.05)、杂草密度和生物量,显著提高田间捕食性节肢动物密度、饲草产量、水分利用效率和食物当量,尤其紫花苜蓿/豌豆间作。紫花苜蓿/豌豆间作更有益于维持农田生态系统多样性和保持作物产量,可作为我国半干旱区可持续农业1种可行有效间作模式。

To find a suitable alfalfa/legume intercropping mode in the semiarid regions in China,a field experiment was conducted in a completely random design.The objective of the study was to explore the effects of alfalfa/legume intercropping models on soil moisture,weed,predatory arthropod,fodder yield,water use efficiency(WUE),and food equivalent unit(FEU)with alfalfa monoculture as a control.Compared to alfalfa monoculture,the fodder yield in alfalfa/hairy vetch,alfalfa/common vetch,and alfalfa/pea intercropping increased by 30.2%,45.2%and 61.3%,respectively,whereas water use efficiency increased by 6.1,8.8 and 12.1 kg·hm^(-2)·mm^(-1),and FEU increased by 26.74%,19.96%and 53.28%.The results demonstrated that alfalfa/legume intercropping modes,especially alfalfa/pea intercropping model,significantly(P<0.05)reduced soil water storage,weed density and biomass,and increased predatory arthropod density,fodder yield,WUE,and FEU.Alfalfa/pea intercropping can be used as a feasible and effective cultivation method for sustainable agricultural production in semiarid regions in China.