长期定位施肥对土壤酶活性的影响及其调控土壤肥力的作用

Effects of long-term fertilization on soil enzyme activities and its role in adjusting-controlling soil fertility

为探讨长期施肥条件下土壤酶活性及其与土壤肥力的关系,对褐潮土肥料定位试验田第12年的土壤酶以及土壤养分因子进行了测定和分析。结果表明,NPK与有机肥长期配合施用能明显提高土壤有机质含量,全氮、全磷及速效氮、磷、钾含量,增强土壤转化酶、磷酸酶和脲酶的活性。玉米秸秆有利于提高土壤转化酶活性,而有机肥则主要提高土壤脲酶和磷酸酶活性;采用轮作方式比连作能更好地培肥土壤。土壤酶活性与土壤肥力之间具有很好的相关性,其中,磷酸酶、脲酶、转化酶活性与有机质、全磷、速效磷含量呈显著正相关;磷酸酶与碱解氮、速效钾,脲酶与速效钾,转化酶与碱解氮均呈显著相关。长期施肥不能增强土壤中过氧化氢酶活性,过氧化氢酶与土壤养分之间无明显相关。

To search for the correlation between soil enzyme activities and soil fertility under the long-term fertilization conditions, enzyme and soil nutrien t through a 12-year fertilization experiment in fluvo-aquic soil were detected an d analyzed. The results were as follows: Long-term application of NPK fertilize r s combined with organic manure could significantly increase the contents of orga nic matter, both of total N, P and available N, P, K . Similarly, the soil phosp hatase, urease and invertase activities were increased. Returning of corn straw into field was helpful to increase soil invertase activity mainly. Farm yard man ure laid particular emphasis on the augment of soil phosphatase, urease activiti es. Crop rotation has more effective than that of continuous cropping to increas e soil fertility. The correlation between soil enzyme activity and soil nutrient content was significant. Positive correlation was found between the activities of phosphatase, urease and invertase and the contents of organic matter, total P and available P. In addition, the positive correlation of phosphatase activity with the contents of available K and alkalified N, urease activity with the cont ent of available K, invertase activity with the content of alkalified N, were si gnificant. Long-term fertilization couldn't increase the soil hydrogen peroxida s e activity. The correlation between hydrogen peroxidase and soil nutrient conten t was not obvious.