施肥和混作对青海省绿肥生长、养分吸收和水氮利用的影响

Effects of fertilization and mixed cropping on green manure growth,nutrient absorption and water and nitrogen utilization in Qinghai province

为了协调绿肥养分的供应和分配,优化麦后复种绿肥模式。在青海省开展大田试验研究化肥添加(不施肥F0、施肥F1)和种植方式(单作箭筈豌豆MC、单作油菜MR、混作箭筈豌豆和油菜MCR)对绿肥生物量、水分利用效率、养分吸收、土壤硝态氮残留以及系统表观氮平衡的影响。结果表明:不论施肥与否,绿肥的总生物量、氮磷钾吸收量和水分利用效率均表现为MC>MCR>MR。施肥显著提高了MCR的生物量和水分利用效率,分别提高了65.01%和83.00%;显著提高了MC的钾素吸收量和MCR的氮磷钾吸收量,分别提高了25.97%、79.73%、74.52%和70.96%。各处理的土壤硝态氮残留量在0~60 cm层均随土层深度呈逐渐增加的趋势,施肥下MC、MR和MCR均主要利用了0~20 cm土层土壤硝态氮,MC和MR施肥均会导致硝态氮向下层土壤淋溶。不同种植方式下表观矿化氮表现为MCR>MC>MR,施肥显著提高了MCR生物固氮和作物吸收氮,分别提高了124.6%和79.7%。本研究可为青海省绿肥种植技术提供科学依据和理论参考。

In order to coordinate the supply and distribution of green manure nutrients,the pattern of multiple cropping of green manure after wheat was optimized.A field experiment was carried out in Qinghai province to study the effects of chemical fertilizer addition(F0:no fertilizer;F1:fertilizer)and planting methods(MC:mono-cropping of common vetch,MR:mono-cropping of rape,MCR:mixed cropping of common vetch and rape)on green manure biomass,water use efficiency,nutrient absorption,soil nitrate nitrogen residue and system apparent nitrogen balance.The results showed that the total biomass,N,P,K uptake and water use efficiency of green manure were MC>MCR>MR,no matter whether fertilizer was applied or not.Fertilization significantly increased the biomass and water use efficiency of MCR by 65.01%and 83%,respectively;The potassium absorption of MC and nitrogen,phosphorus and potassium absorption of MCR were significantly increased by 25.97%,79.73%,74.52%and 70.96%,respectively.The residual amount of soil nitrate nitrogen in the 0~60 cm layer of each treatment increased gradually with the depth of the soil layer.Under fertilization,the soil nitrate nitrogen in the 0~20 cm layer of MC,MR and MCR treatments was mainly used,and fertilization would lead to nitrate nitrogen leaching to the lower soil for MC and MR.Under different planting patterns,the apparent mineralized nitrogen showed as MCR>MC>MR.Fertilization significantly improved the biological nitrogen fixation of MCR and the nitrogen absorption of crops by 124.6%and 79.7%,respectively.This study can provide scientific basis and theoretical reference for green manure planting technology in Qinghai province.