包膜控释尿素对保护地菜地土壤肥力及酶活性的影响

为探讨包膜控释尿素施用条件下土壤酶活性及其与土壤肥力的关系，对种植黄瓜、番茄、辣椒等蔬菜的保护地菜地土壤酶活性以及土壤养分因子含量进行了测定和分析。结果表明，施用包膜控释尿素比普通尿素能明显提高土壤有机质、全氮、碱解氮、硝态氮、铵态氮、速效钾含量，降低了土壤速效磷含量；包膜控释尿素可增强土壤多酚氧化酶、磷酸酶、脲酶活性，这些酶活性与土壤养分之间具有极显著或显著的相关性，施用包膜控释尿素未增强过氧化氢酶、转化酶的活性，过氧化氢酶、转化酶与土壤养分因子相关性不明显。在评价土壤酶活性与土壤养分的关系方面要根据不同的作物作具体的分析。

Effects of Controlled Release Coated Urea on Soil Fertility and Enzyme Activities of Protected Vegetable Field

In order to investigate the relationship between soil enzyme activities and soil fertility with controlled release coated urea application, soil samples from protected vegetable field grown with cucumber, tomato and pepper were taken, and soil enzyme acitivities as well as nutrient content were determined. Results showed that application of coated urea significantly improved soil organic matter, total N, alkali soluble N, nitrate, ammonium, available potash, and decreased available P content in comparison to urea. Coated urea application increased the activities of polyphenol oxidase, phosphatase, and urease, which were significantly correlated with soil nutrient factors. However, coated urea application did not increased the activities of catalse and invertase, and no significant relationship was observed between catalse and invertase and soil nutrient factors, It is concluded that it is important to consider specific crop when studying the relationship between soil enzyme activities and soil nutrient.