覆盖与种植模式对土壤呼吸速率和玉米根际微生物数量的影响

Effects of mulching and planting methods on soil respiration rate and rhizosphere microbes of maize

研究覆盖材料(普通地膜覆盖、生物可降解地膜覆盖、秸秆覆盖和无覆盖)与种植模式(玉米单作、玉米间作豌豆和玉米间作箭筈豌豆)对土壤呼吸速率和玉米根际微生物数量的影响,结果表明:土壤呼吸日变化曲线因覆盖与种植模式而异,峰值出现时间也各不相同;同一种植模式下,玉米生育期平均土壤呼吸速率由高到低依次为普通膜>生物膜>裸露种植>秸秆,玉米根际土壤微生物总数由高到低依次为秸秆>生物膜>普通膜>裸露种植;不同种植模式,与玉米单作相比,玉米间作豌豆和玉米间作箭筈豌豆的全生育期平均土壤呼吸速率分别提高35%和25%,根际土壤微生物总数提高38.14%和84.75%;经相关分析,土壤呼吸与根际微生物数量呈不显著正相关关系,即土壤呼吸速率受根际微生物的影响,但根际微生物不是影响土壤呼吸的主要因子。试验表明,秸秆覆盖降低土壤呼吸速率,提高根际微生物数量;间作不同程度提高土壤呼吸速率和根际微生物数量。

The effects of film mulching（common plastic film,biodegradable film,straw film and CK）and planting methods（monoculture maize,maize/common vetch intercropping and maize/hairy vetch intercropping）on soil respiration rate and rhizosphere microbes were studied.The result indicated that the diurnal variation of soil respiration rate and peak value varied with film mulching and planting methods.The order of average soil respiration rate in maize growth periods was common plastic film mulching,biodegradable film mulching,no film mulching and straw film mulching with the same planting method,while the order of average rhizosphere microbe population was straw film mulching,biodegradable film mulching,common plastic film mulching and no film mulching.Compared with monoculture,the soil respiration rates in maize/pea and maize/common vetch were increased by 35% and 25%respectively.While the total rhizosphere microbe populations were increased by 38.14% and 84.75 %respectively.Correlation analysis showed that the soil respiration rate was positively correlated with rhizosphere microbe population（not significantly）,which suggested that the rhizosphere microorganisms affected soil respiration rate,but it was not a main factor.It could be concluded that the straw film mulching decreased the soil respiration rate but increased the rhizosphere microbe.And the intercropping increased the soil respiration rate and rhizosphere microbial populations at different degrees.