论文部分内容阅读
为探索苏中地区适宜的秸秆还田量对土壤肥力和产量的影响,通过开展大田定位试验,研究稻麦轮作条件下不同周年秸秆还田量对农田土壤养分、微生物活性以及作物产量的影响.试验共设计5个处理,分别以25%、50%、75%和100%秸秆还田量为梯度,以秸秆不还田为对照.经过3年定位试验,结果表明:(1)不同秸秆还田量能不同程度地增加土壤养分和有机质含量,土壤全氮、有效磷和有机质以75%还田量最为显著,分别比对照提高了2.61%、6.31%和5.90%,而速效钾含量则以50%还田量最为显著,较对照提高了24.08%;(2)不同秸秆还田量对土壤细菌和放线菌数量均有不同程度的激活,且以50%还田量达到显著水平,分别比对照提高了14.85%和24.58%,而真菌与之不同,除75%还田量处理外均有不同程度的抑制作用;(3)50%和75%还田量显著提高了土壤蔗糖酶和过氧化氢酶活性,而土壤脲酶活性则以50%和100%还田量提升效果显著;(4)周年粮食产量随还田量的增加呈先增加后减少的趋势,以75%还田量增产显著,增幅为10.01%.综合考虑,在该地区稻麦轮作条件下,以50%或75%秸秆还田量为宜,可显著提高土壤肥力,增加作物产量.
In order to explore the effects of straw return on soil fertility and yield in central Jiangsu Province, field experiments were conducted to study the effects of straw return to paddy fields on soil nutrient, microbial activity and crop yield under the conditions of rice and wheat rotation. A total of 5 treatments were designed, with 25%, 50%, 75% and 100% straw returning as the gradient, respectively, with straw returning as control.After 3 years positioning test, the results showed that: (1) The soil fertility and organic matter content increased with soil fertility to a certain extent. Soil total N, available P and organic matter were the most significant with 75% return to field respectively, which increased by 2.61%, 6.31% and 5.90% 50% return to the most significant, compared with the control increased by 24.08%; (2) different amount of straw on soil bacteria and actinomycetes have varying degrees of activation, and reached a significant level of 50% Which were 14.85% and 24.58% higher than that of the control. However, the fungi had different degrees of inhibition except 75% of field treatment; (3) 50% and 75% Catalase activity, while soil urease activity was 50% and 100% also (4) The annual grain yield increased firstly and then decreased with the increase of the amount of returning field, yielding a significant increase of 75%, with an increase of 10.01% .In comprehensive consideration, under the conditions of rice and wheat rotation in this area , With 50% or 75% of straw is appropriate, can significantly improve soil fertility and increase crop yield.