Abstract: To find the suitable planting mode of clover living mulches in semiarid regions in China, a field experiment was conducted in a completely random design. We explored the effects of clover living mulches on soil moisture, weed density and biomass, predatory arthropod density, and fodder and crop yield with no mulches as a control in maize and soybean production systems. Compared to no mulches in maize production, soil water storage, weed density and biomass under clover living mulches decreased by 6.6%-10.0%, 2.6%-65.6%, and 26.8%-89.2%, respectively, while the predatory arthropod density, maize fodder yield, and crop yield under clover living mulches increased by 22.2%-100.0%, 11.1%, and 5.7%, respectively. Compared to no mulches in soybean production, soil water storage, weed density and biomass, and soybean grain yield under clover living mulches decreased by 6.9%-21.9%, 36.2%-65.2%, 29.9%-62.4%, and 0.8%, respectively, while the predatory arthropod density and soybean fodder yield under clover living mulches increased by 25.0%-250.0%, and 259.0%, respectively. Clover living mulches significantly reduced soil water storage, weed density and biomass, and increased predatory arthropod density in maize and soybean production systems. However, clover living mulches did not affect fodder yield and grain yield of maize and soybean. The competition between clover and soybean was higher than that between clover and maize under clover living mulches. Therefore, clover living mulches were beneficial to maintaining cropland ecosystem diversity and crop yield in maize and soybean production. The clover living mulches in maize production can be used as an effective cultivation technology for sustainable agricultural production in semiarid regions in China.

Key words: biological diversity, sustainable agriculture, competition.