六种稻田土壤冬季种植黑麦草功能效应研究

选取我国亚热带地区6种主要成土母质发育的水稻土，通过定位试验研究了黑麦草产量、碳氮环境效应和土壤微生物量变化。结果表明，6种稻田土壤冬季均适合生长黑麦草，黑麦草地上部和根系干物质产量，在河沙泥田表现最好，分别为11 324.8 kg hm^-2和8 227.3 kg hm^-2。6种稻田土壤黑麦草地上部和根系碳蓄积量均存在显著差异(P＜0.05)，地上部分碳蓄积量在河沙泥田最高，为4 495.3 kg hm^-2；根系碳蓄积量在河沙泥田和麻沙泥田表现最好，分别为2 799.6 kg hm^-2和2 711.8 kg hm^-2；黄泥田最低，为1 852.9 kg hm^-2。而黑麦草氮蓄积量，在河沙泥田最高，地上氮蓄积量为238.1 kg hm^-2，地下氮蓄积量为60.1 kg hm^-2。6种稻田土壤微生物量碳和土壤微生物量氮，在种草区和冬闲田间差异均达到了显著水平(P＜0.05)，除灰泥田外种草区均大于冬闲田，冬季种植黑麦草增加了土壤微生物商。

Function of Winter Ryegrass Grown in Six Different Types of Paddy Soils

The total amount of winter fallow areas have increased in south China in recent years.It not only causes enormous waste of resources and energies,but also affects paddy soil qualities and farming environment.Winter ryegrass was essential to improve soil productivity and carbon and nitrogen fixation.The purposes of this study were to investigate the effects of winter ryegrass on carbon and nitrogen fixation and the change of soil microbial biomass carbon and soil microbial biomass nitrogen in six different types of paddy soils in south China.The experiment designed winter ryegrass and winter fallow respectively in six different types of paddy soils.The result showed that,winter ryegrass dry matter was significant in different types of paddy soils.Ryegrass biomass was the highest in alluvial sandy soil with 11 324.8 and 8 227.3 kg ha-1 respectively in aboveground and root.The carbon uptake in aboveground and root of ryegrass was 4 495.3 and 2 799.6 kg ha-1 respectively in alluvial sandy soil.The nitrogen uptake in aboveground and root of ryegrass was 238.1 and 60.1 kg ha-1 respectively.The change of soil microbial biomass carbon(SMBC),soil microbial biomass nitrogen(SMBN) was significant between winter ryegrass and winter fallow treatments in six different types of paddy soils.Winter ryegrass increased soil microbial activities,especially in alluvial sandy soil.