长期施肥对红壤性水稻土微生物生物量与活性的影响

土壤微生物及其活性是指示土壤增肥过程和土壤环境变化的灵敏指标.本文研究了红壤荒地开垦为水田后不同施肥制度定位施肥 16 年后水稻土的微生物生物量与活性特征,结果表明:经 16 年水稻耕植,不同施肥措施下土壤的微生物生物量和活性还处于较低水平.施肥制度显著影响了水稻土的微生物生物量 C 和基质诱导呼吸,但对基础呼吸的影响还不明显.只施用 N、K 肥对提高土壤微生物生物量和活性没有显著效果,在不施肥或施用化肥的基础上配合有机循环可以显著提高土壤微生物的生物量、代谢活性和微生物呼吸的温度敏感性,N、P、K 肥配合有机循环的施肥制度对提高土壤微生物生物量和代谢活性的作用最好.

Long-term effects of fertilization on microbial biomass and activities of red paddy soils

Soil microbial biomass and activity are sensitive indices to soil fertility promotion and soil environmental changes. In this paper, the responses of microbial biomass and respiration to the different fertilization managements in paddy soils cultivated from wasteland in red soil region were studied. The results showed that, after 16 years of rice cropping, the microbial biomass of activity of red paddy soils under all fertilizations were still in low level. The fertilization managements affected microbial biomass carbon (MBC) and substrate-induced respiration (SIR) significantly, with the exception of basal respiration (BR). Compared with the no fertilizer treatment (CK), nitrogen and potassium fertilizers did not affect microbial biomass and activity evidently. The microbial biomass, metabolizing activity and temperature sensitivity of microbial respiration were promoted by the application with organic cycling. Among of all fertilization treatments, composed application of chemical fertilizer and organic cycling promoted the soil microbial biomass and metabolize activity most.