不同水分管理方式对稻田土壤生物学特性的影响

在下辽河平原单季稻地区研究了常规浅湿干灌溉 (CK)、浅湿干灌溉薄膜阻渗 (IC)、湿润灌溉薄膜阻渗 (MC)、淹水灌溉薄膜阻渗 (FC) 4种不同水分管理方式下土壤线虫及土壤微生物量的动态变化。结果表明 ,耙耕前 ,CK、FC处理食细菌线虫数量显著高于MC、IC处理 ;薄膜阻渗在黄熟期显著降低了土壤食细菌线虫的数量 ,在耙耕前显著降低了食真菌线虫数量。潮棕壤稻田食真菌线虫与食细菌线虫相比数量较低。在耙耕前不同水分管理方式下土壤微生物量C显著低于对照。不同水分管理方式在水稻分蘖期、抽穗期对食细菌线虫数量、食真菌线虫数量、微生物量C和微生物量N没有影响。土壤食细菌线虫、食真菌线虫数量与土壤微生物量C、N没有达到显著相关。

Effects of water regimes on soil biological properties in a paddy field

Effects of water regimes on soil biological properties were investigated in a field study during a rice (Oryza sativa L.) growing season in the Lower Reaches of Liaohe Plain.The number of bacterial-feeding nematodes at pre-tillage stage was higher in CK and FC than in MC and IC.Percolation-controlling markedly decreased the number of bacterial-feeding nematodes at yellow ripeness stage and that of fungal-feeding nematodes at pre-tillage stage.The number of fungal-feeding nematodes was found to be lower than that of bacterial-feeding nematodes in aquic brown soil.Percolation-controlling significantly decreased soil microbial biomass C at pre-tillage stage.Water regimes exhibited no effects on bacterial-feeding nematodes,fungal-feeding nematodes,microbial biomass C and microbial biomass N during rice tillering and heading stages.No significant correlations were found between the number of bacterial-feeding nematodes,fungal-feeding nematodes and C,N in microbial biomass.