安徽单季稻田绿肥优化配置与稻季氮肥减施效果研究

Optimized configuration of green manure and the effect of nitrogen fertilizer reduction on single cropping paddy field in Anhui

为了研究豆科和禾本科绿肥适宜的种植模式,提高绿肥的养分资源高效利用。在绿肥季设置了6个处理:(1)冬闲、(2)紫云英单播、(3)毛叶苕子单播、(4)黑麦草单播、(5)紫云英和黑麦草混播、(6)毛叶苕子和黑麦草混播;并在水稻季对5个绿肥处理进行减氮30%,冬闲处理设置常规施肥和减氮30%处理。结果表明,与单播相比,混播增加了鲜草产量,毛叶苕子和黑麦草混播处理鲜草产量最高(31 582 kg·hm^(-2)),同时其氮素积累量显著高于紫云英和黑麦草处理;种植绿肥有利于提高土壤的养分含量,其中黑麦草有机质含量提升最大,较冬闲处理增幅11.25%,豆科和禾本科绿肥混播后,土壤全氮和速效钾的含量显著高于单播黑麦草处理;同时利用冬闲田种植利用绿肥有利于提高水稻产量,其中毛叶苕子、毛叶苕子+黑麦草、紫云英、紫云英+黑麦草处理的水稻产量与100%N处理无显著差异。综上,毛叶苕子和黑麦草混播种植不仅增加绿肥鲜草产量和养分积累量,且提高土壤肥力,同时在减施氮肥下仍获得稳产,是本试验区域内最优的混播种植模式。

In order to study the suitable planting mode of leguminous and gramineous green manure and im-prove the efficient utilization of nutrient resources of green manure,six treatments were set up in the green manure season:(1)winter fallow,(2)milk vetch monoculture,(3)hairy vetch monoculture,(4)ryegrass monoculture,(5)mixed sowing of milk vetch and ryegrass,(6)mixed sowing of hairy vetch and ryegrass,five green manure treat-ments were reduced by 30%nitrogen in the rice season,and conventional fertilization and 30%nitrogen reduction were set up in the winter fallow treatment.The results showed that compared with monoculture,mixed sowing in-creased the fresh grass yield,and the fresh grass yield of mixed sowing of hairy vetch and ryegrass was the highest(31582 kg·hm^(-2)),and the nitrogen accumulation was significantly higher than that of the milk vetch and ryegrass treatments.Planting green manure was beneficial to improving the nutrient content of soil,and the organic matter content of ryegrass increased the most,which was 11.25%higher than that in the winter fallow treatment.After mixed sowing of legume and gramineous green manure,the content of total nitrogen and available potassium in soil was significantly higher than that in single sowing ryegrass treatment.At the same time,the use of green manure in winter fallow field is beneficial to the increase of rice yield.Among them,the rice yield of hairy vetch,hairy vetch+ryegrass,milk vetch,milk vetch+ryegrass treatment was not significantly different from that of 100%N treatment.In summary,the mixed planting of hairy vetch and ryegrass not only increases the yield and nutrient accumulation of green manure fresh grass,but also improves soil fertility.At the same time,stable yield was still obtained under re-duced nitrogen fertilizer application,which is the optimal mixed planting mode in this test area.