氮营养水平对植烟土壤养分含量及土壤酶活性的影响

摘要

田间试验研究了植烟土壤不同土层养分含最及土壤酶活性的变化规律.结果表明:在同一氮水平条件下,随着土层深度的增加,土壤有机质、全氮、速效氮、速效磷、速效钾以及土壤脲酶,蛋白酶,转化酶活性均呈降低趋势,通过方差分析可知,各处理间差异达到5%显著水平;0～40cm土层范围内,随着施氮量的增加,土壤有机质、全氮、速效氮含量也增加,土壤脲酶活性增加,而蛋白酶活性呈降低趋势,转化酶活性呈先增加后降低的趋势,且在该土层范围内,酶与土壤养分之间存在显著或极显著的相关关系;60～80cm土层范围内,氮对土壤养分及土壤酶的影响能力相对降低.以上说明在植烟土壤-土壤养分-土壤酶相互作用的系统中,土壤养分含量和土壤酶活性明显受氮营养水平和土层深度的共同影响.%Field experiment was conducted to study the variation rules of nutrient content and soil enzyme activities in different soil layers. Results showed that at same nitrogen level, content of soil organic matter, all nitrogen, available nitrogen, available phosphorus, potassium, and activities of soil urease, protease, invertase all decreased with increasing of soil depth.Analysis of variance showed that difference among treatments reached at 5 ％ significant level. At 0-40 cm soil depth, with increasing of nitrogen application ,content of soil organic matter, all nitrogen, and available nitrogen increased,s oil urease activity increased while that of soil protease decreased, invertase activityfirstly increased and then decreased. And significant positive correlations were found between enzyme activities and soil nutrients. At 60-80 cm soil depth, effects of nitrogen on soil nutrients and enzyme activities relatively decreased. It indicated that in tobacco soil-soil nutrient-soil enzyme interaction systems,soil nutrient content and soil enzyme activities were significantly affected by nitrogen level and soil depth.