施肥对黑土土壤微生物生物量碳的作用研究

Effect of fertilization on soil microbial biologic carbon in black soil

长期施肥对黑土耕地表层土壤微生物生物量碳 (MBC)的作用研究结果表明 ,NPK化肥配施可保持休闲地土壤微生物生物量碳含量至 1.6g/kg水平 ;高量有机肥与无机肥配施可比休闲地土壤微生物生物量碳含量提高 1.96～ 2 .75倍 ;长期耕种与施肥对土壤微生物生物量碳含量产生衰减影响 ;各处理土壤微生物生物量碳含量增加依次为M2 +NPK(+14 1.2 5 % ,1990年始处理 ) >M4+NPK(+12 6 .88% ) >M2 +NPK(+10 1.2 5 % ,1980年始处理 ) >M4+CK(+80 .6 3% ) >(M1+NPK)× 1.5 (+13.13% ) >NPK(+8.12 % ) ,各处理土壤微生物生物量碳含量减少依次为M0+NPK(- 3.75 % ) >M1+NPK(- 17.5 0 % ) >M2 +CK(- 30 .6 3% ) >CK(- 4 7.5 0 % ) >M0 +CK(- 6 1.88% )。

There are many changes in the soil microbial biologic content during the application of fertilizer in the surface of black soil for a long time. The results show that the assorted usage of nitrogen, phosphate and potassium fertilizer can keep the MBC of fallow arriving to 1.6g/kg; the assorted usage of high amount of organic and inorganic fertilizer can increase 1.96～2.75 times than that of fallow; a long time of fertilization and cultivation results in the microbial biologic content (MBC) attenuation; in all treatments, the percent of MBC increases from bigger to smaller, being M 2+NPK (+141.25%, begin in 1990)>M 4+NPK(+126.88%)>M 2+NPK(+101.25%, begin in 1980)>M 4+ CK(+80.63%)>1.5(M 1+NPK)(+13.13%)>NPK(+8.12%), the percent of MBC decreases from smaller to bigger, being M 0+NPK(-3.75%)>M 1+NPK(-17.50%)>M 2+CK(-30.63%)>CK(-47.50%)>M 0+ CK(-61.88%).