覆膜和施化肥对土壤有机碳含量及玉米、大豆产量的影响

Effects of Film Mulching and Chemical Fertilizer Application on Soil Organic Carbon Content and Corn and Soybean Yield

以贵州安顺大田试验为依托,设置4个处理:不覆膜不施肥(non-F+CK)、不覆膜施肥(non-F+NP)、覆膜不施肥(F+CK)和覆膜施肥(F+NP),探究覆膜和施肥对土壤有机碳和玉米、大豆产量的影响,为贵州农田土壤固碳培肥和作物产量提升提供理论依据。结果表明:覆膜或施肥对土壤有机碳(SOC)影响不显著;施肥和不施肥条件下覆膜后土壤微生物生物量碳(MBC)含量分别降低了9.1%和10.2%,施肥使土壤MBC显著增加了8.2%~32.5%;施肥对土壤全氮(TN)的增加幅度在2.9%~76.5%之间,施肥和不施肥条件下覆膜处理的TN分别降低了11.4%(P<0.05)和4.4%;与non-F+NP相比,F+NP处理玉米大豆分别增产10.4%和28.6%;SOC与土壤MBC和TN呈正相关,MBC与TN呈显著正相关关系,与C/N呈负相关,玉米和大豆产量均与MBC呈显著正相关。综上,覆膜不利于SOC和MBC含量的增加,施肥则相反,将覆膜与施肥相结合可增加玉米和大豆产量。

The field experiment in Anshun,Guizhou,examined the effects of film mulching and fertilization on soil organic carbon and corn and soybean yield.Four treatments were set up:non-film mulching without fertilization(non F+CK),non-film mulching with fertilization(non F+NP),film mulching without fertilization(F+CK),and film mulching with fertilization(F+NP).The results showed that mulching or fertilization did not significantly affect soil organic carbon(SOC).The soil microbial biomass carbon(MBC)content decreased by 9.1%and 10.2%after plastic film mulching under conditions of fertilization and no fertilization,respectively.However,fertilization led to a significant increase in soil MBC,ranging from 8.2%to 32.5%.The increase in TN due to fertilization varied from 2.9%to 76.5%,while there was a decrease of 11.4%(P<0.05)and 4.4%in TN under fertilization and no fertilization conditions,respectively.Compared with non-F+NP,F+NP treatment increased the yield of corn and soybean by 10.4%and 28.6%,respectively.The soil SOC had a positive correlation with both soil MBC and TN,and MBC and TN were also positively correlated with each other,but they were negatively correlated with C/N.The yields of corn and soybeans had a strong positive correlation with MBC.To sum up,plastic film mulching does not promote the increase of SOC and MBC content,whereas fertilization has the opposite effect.However,when combined,plastic film mulching and fertilization can lead to higher corn and soybean yields.