Effects of Rice Cultivation Pattern on Yield of After-Crop and Soil Microbial Biomass

A field experiment designed to have four treatments,grass mulch(GC),film mulch(FM),bare(LL),and submerged(SZ),was conducted to study effects of rice cultivation pattern on yield and biomass of its after-crop,barley,soil microbial biomass and nitrogen fertilizer use efficiency.Results show that(1)Treatment GC was the highest in grain yield of barley,about 6.0%,16.4% and 37.0% higher than Treatments FM,LL and SZ,respectively;(2)Treatment GC was also the highest in biomass of the barley at its harvest stage,and about 3 424,6 059 and 6 961 kg·hm^-2 higher than Treatments FM,LL and SZ,respectively;(3)soil microbial biomass carbon and nitrogen increased first and then decreased with the growth of barley in all the four treatments,which appeared to be in a decreasing order of GC>FM>LL>SZ;and(4)Treatment GC was also the highest in nitrogen fertilizer use efficiency,and about 0.9,2.2 and 8.0 kg·kg^-1 higher than Treatments FM,LL and SZ,respectively,and a similar trend was observed of nitrogen production rate showing that Treatment GC was 2.8,7.0 and 13.3 kg·kg^-1 higher than Treatments FM,LL and SZ,respectively.The findings suggest that Treatment GC is an optimal cultivation pattern in rotation with barley.