冀南平原盐渍化改造区土壤过氧化氢酶活性变化研究

Soil Catalase Activities in Salinized Rehabilitation Area of the Southern Hebei Plain

本研究基于华北平原区的少耕培肥长期定位试验(1985年至今),以冬小麦--夏玉米轮作体系为研究对象,研究了长期施用氮磷肥、不同耕作方式结合秸秆还田对土壤过氧化氢酶活性的影响。结果表明:土壤过氧化氢酶活性与土壤温度的相关性极显著,冬小麦和夏玉米生长季两者间的相关系数分别为:0.738**和0.907**,说明在一定范围内温度增强了酶与底物的亲和力、提高了酶的活性。土壤酶的活性与施肥等因素有一定的相关性:氮肥施用量对土壤过氧化氢酶的活性影响不大(P>0.05);无论是小麦季还是玉米季,随着磷肥施用量的增加,土壤过氧化氢酶的活性呈现明显的下降趋势,说明施用磷肥明显抑制了土壤过氧化氢酶的活性(P<0.05);随着秸秆还田量的增加,土壤过氧化氢酶的活性表现出了增加的趋势,但效果不显著(P>0.05)。不同耕作方式对土壤过氧化氢酶活性的影响不显著(P>0.05)。总之,在少耕条件下,不施用磷肥、少施用氮肥(225 kg N hm^-2a^-1)和高量秸秆(4500 kg hm^-2a^-1)的处理有利于提高过氧化氢酶的活性。

Based on the long-term experiment of minimum-tillage and soil fertilization for 27 years,the influence of fertilization and tillage on soil catalase activities(SCA)was investigated in the winter wheat-maize rotation system in North China plain.The results showed the SCA was very significantly related with soil temperature(with a correlation coefficient of 0.997**and 0.973**),which indicated that soil temperature increased the affinity of the catalase and zymolyte and the SCA.The impact of nitrogen(N)fertilizer on the SCA was not obvious(P>0.05);The SCA showed an obviously downward trend(P<0.05),with the amount of phosphorus(P)fertilizer due to the inhibition of SCA,during the wheat and maize growth stages.The straw returning to soil increased the SCA,but the impact was not obvious(P>0.05).The impact of tillage modes on the SCA was not obvious(P>0.05).No P fertilizer,N fertilizer applied at 225 kg and straw returning at 4500 kg hm^-2a^-1 under minimum tillage increased soil catalase activities.