【摘要】 通过设置在北京昌平区的长期肥料定位试验,研究16年的长期不同施肥制度下,土壤微生物生物量碳、氮、磷的状况。试验设置冬小麦-夏玉米复种连作和小麦-玉米→小麦-大豆复种轮作2种不同种植制度以及长期撂荒处理(CK0),其中冬小麦-夏玉米复种连作种植制度(种植方式Ⅰ)包括4个施肥处理,分别为:对照(CK,不施肥,但种植作物)、氮磷钾(NPK)、氮磷钾+猪厩肥(NPK+M)、氮磷钾+玉米秸秆(NPK+S);小麦-玉米→小麦-大豆复种轮作种植制度(种植方式Ⅱ)包括1个施肥处理为氮磷钾+种植方式Ⅱ(NPKF)。试验结果表明:1)长期撂荒土壤的有机质和全氮的含量、微生物量碳(SMB-C)和氮(SMB-N)均显著高于2种不同种植制度的农田土壤,但土壤微生物生物量磷含量较低;2)2种不同的种植制度中,施肥处理(NPK、NPKM、NPKS和NPKF)农田的土壤养分含量、微生物量生物量碳、氮、磷均高于不施肥但种植的农田(CK),与CK相比,NPK、NPK+M、NPK+S和NPKF处理的微生物量生物量碳增加了26%、70%、36%和46%,微生物量生物量氮增加了92%、251%、130%和159%,以及微生物量生物量磷增加了519%1、495%、898%和712%;3)小麦-玉米→小麦-大豆复种轮作并且施氮磷钾肥(NPKF)农田的土壤微生物量生物量碳、氮和磷高于长期小麦-夏玉米复种连作并且施氮磷钾肥(NPK)的农田;4)在施肥处理中(NPK、NPK+M、NPK+S和NPKF),长期氮磷钾化肥与有机肥配合施用的处理(NPK+M)的土壤上述指标高于其他施肥处理(NPK、NPK+S和NPKF);5)土壤微生物与土壤养分之间具有很好的相关性,其中土壤微生物生物量碳、氮与土壤有机质、全氮呈极显著的正相关,土壤微生物生物量磷与土壤全磷和速效磷呈显著正相关。更多还原

【Abstract】 A study of soil microbial biomass carbon(SMB-C),microbial biomass nitrogen(SMB-N),and microbial biomass phosphorus(SMB-P) in arable soils with different fertilizer regimes was carried out based on a 15-year long term fertilizer experiment in a Fluvo-aquic soil in Beijing.Thirteen treatments were established in 1990.Six treatments were chosen for this work: Four were in a wheat-maize rotation receiving either no fertilizer(CK),mineral fertilizers(NPK),mineral fertilizers plus farmyard manure(NPKM) or mineral fertilizers with maize straw incorporated(NPKS).One treatment was in a wheat-maize/wheat-soybean rotation receiving NPK(NPKF).The other was an abandoned arable land(CK0) colonized by weeds.The amount(kg/hm 2) of chemical fertilizer per year was 150 N,75 P 2O 5,45 K 2O,and(t/hm 2) 22.5 manure and 2.25 maize straw.The main results were as follows: The soil organic C(SOC)and total N(STN)as well as microbial biomass C and N were higher in long-term(15 years) abandoned arable soils than in cultivated arable soils.However,the microbial biomass P in the fallow soil was lower than that in treatments with fertilizer application.The soil nutrient concentration and microbial biomass C,N and P were higher in treatments with fertilizer application(NPK、NPKM、NPKS and NPKF) than the no fertilizer treatment(CK).The above soil parameters were also higher in wheat-maize/wheat-soybean rotation than continuous wheat-maize cropping system.Among the fertilizer application treatments,NPKM had relatively higher soil nutrients and microbial biomass C,N and P than other fertilizer treatments(NPK、NPKS and NPKF).The correlation between soil microbial biomass and soil fertility was significant.There was a positive correlation between the soil microbial biomass C & N and the contents of organic matter and total N.A positive correlation was also found between the soil microbial biomass P and Total P and Olsen P.更多还原