秸秆还田对稻田生态系统环境质量影响的初步研究

为了得到较好的还田方式及还田量，采用不同的处理对早、晚稻分别进行研究。通过采用覆盖还田、粉碎还田和堆肥还田这3种不同的秸秆还田方式，对秸秆还田后对早稻生长及产量、品质的影响以及对土壤肥力状况的影响进行研究。晚稻处理中，在秸秆还田的同时，通过配施不同种类和数量的化学肥料以及降解菌来研究晚稻土壤生物活性变化（微生物区系变化、土壤酶活性变化）。结果表明：对于早稻产量及土壤养分状况方面，粉碎还田3000 kg/hm2相比其他处理来说都有较好的效果；对于晚稻土壤微生物及酶活性变化方面，秸秆还田的同时配施复合肥能有效地增加土壤中细菌的数量，其中粉碎还田3000 kg/hm2+225 kg/hm2复合肥的细菌数量最多。秸秆还田配施一定的化学肥料能够增加过氧化氢酶和脲酶的含量，但是对于土壤中转化酶的影响不大。

The Preliminary Research about the Influence of Rice-Straw Returning on the Rice Ecosystem

To study the better rice-straw returning, this experiment used different treatment on early and late rice respectively by using coverage returning, stubble breaking land-returning and compost counters-field these three different rice-straw returning. After rice-straw returning, to study the early rice growth, yield quality and influence the status of soil fertility, in order to get the better rice-straw returning. In the late rice processing, in the meanwhile, through the rice-straw returning with different types and quantity the chemical fertilizer and degradation bacterium to study the late rice soil biological activity changes （micro-flora change, soil enzymes activity change）. The resuhs showed that for early rice yield and soil nutrient status, compared 3000 kg/hm2 stubble breaking land-returning both other treatment had good effect. For late rice on trend of microbe and enzyme, rice-straw returning with the chemical fertilizer could effectively increased the number of bacteria in the soil, including stubble breaking land-returning 3000 kg/hm2 plus 225 kg/hm~ compound fertilizer with the highest number of bacteria. The rice-straw returning with the chemical fertilizer and degradation bacterium could increased catalase and urease activity, but not affected obviously in soil invertase