有机替代下麦后复种绿肥的土壤培肥效应

Effects of organic fertilizer partially replacing mineral fertilizer on soil fertility of green manure planted after spring wheat

明确夏休闲期种植并翻压不同绿肥对不同施肥处理麦田土壤主要肥力性状的影响,为提高滴灌麦田土壤质量提供理论及数据支持。通过两年的田间定位试验,在3种施肥方式(CK:不施肥、CF:常规施用氮磷肥、OF:有机肥替代20%化肥,均已连续3年)下设置两个绿肥处理(DD:大豆,YK:油葵)及休闲对照(XX),分别在绿肥生育期20、40、60 d测定绿肥植株干物质、养分积累及土壤理化性质。结果表明,2020年和2021年不同施肥处理的绿肥产量均为OF最高,两种绿肥生物量均表现为YK>DD;绿肥翻压第二年,OF-YK生物量为68213.9 kg·hm^(-2),其地上部N、P、K积累量分别为200.6、64.5、340.9 kg·hm^(-2);OF-DD收获期土壤碱解氮增加了15.1%,OF-YK收获期土壤速效钾含量增加了6.5%。不同绿肥处理土壤含水量2年均表现为绿肥>休闲;不同施肥处理土壤有机碳(SOC)、全氮(TN)含量均表现为OF>CF>CK,不同绿肥处理SOC表现为YK>DD>XX,TN表现为DD>YK>XX。2021年与2020年相比,XX处理SOC减少了2.6%,TN减少了6.9%;OF处理2021年与2020年相比,YK的SOC增加了5.9%,DD的TN增加了1.22%。综上,大豆、油葵填闲并还田能够有效改善土壤水分条件,提高土壤TN、SOC、碱解氮、速效钾含量;具有培肥土壤、提高土壤SOC含量的作用;大豆绿肥填闲具有结合减量施用氮肥进而改善农田生态的潜能,有机替代20%化肥结合油葵绿肥能够增碳培肥土壤。

In order to provide a theoretical and data support for improving the soil quality of drip irrigation wheat field,a 2-year field experiment was conducted in the northern piedmonts of Tianshan area to investigate the effect of different green manures on the main fertility properties of wheat field soil.Two green manure treatments and fallow control(DD:soybean,YK:sunflower,XX:fallow control)were set up under three fertilization methods(CK:no fertilizers,CF:conventional application of nitrogen and phosphorus fertilizers,OF:20%mineral fertilizers replaced by organic fertilizers.These treatments had been going on for 3 years),the plant dry matter,nutrient accumulation and soil physical and chemical properties were measured at 20,40 and 60 days of the green manure growth.The results showed that the yield of green manure in different treatments in 2020 and 2021 was the highest in OF treatment,and the biomass of the two green manures showed YK>DD.In 2021,the biomass of OF-YK was 68.2 t·hm^(-2),and the accumulation of N,P and K in shoot was 200.6,64.5 and 340.9 kg·hm^(-2),respectively.Soil available nitrogen content increased by 15.1%at OF-DD harvest stage,and soil available potassium content increased by 6.5%at OF-YK harvest stage.The soil water content of different green manure treatments showed green manure>fallow for both years;the organic carbon(SOC)and total nitrogen(TN)contents of different fertilization treatments all showed OF>CF>CK,and the SOC of different green manure treatments showed YK>DD>XX,TN performance was:DD>YK>XX.Compared with 2020,the SOC of XX treatment in 2021 reduced by 2.6%,and the TN reduced by 6.9%.Compared with 2020,the SOC of OF treatment in 2021 increased by 5.9%,and the TN of DD increased by 1.22%.In conclusion,Soybean and sunflower returning to the field can effectively improve soil moisture conditions,increase soil total nitrogen,organic carbon,soil available nitrogen,and available potassium content;it has the function of fertilizing the soil and increasing the soil organic carbon content;multiple cropping of soybean has the potential to improve farmland ecology by reducing nitrogen application.20%of mineral fertilizer replaced by organic fertilizer combined with sunflower green fertilizer can increase soil carbon content and improve soil fertility.