包膜尿素在胶园土壤中养分释放特性研究

Nitrogen Release Characteristics of Coated Urea in Rubber Plantation Soils

为了探讨包膜尿素应用于橡胶树施肥管理中的可行性,本文通过田间土壤埋袋法,研究了3种包膜尿素在胶园土壤中的养分释放特性,并对包膜尿素养分累积释放率与积温进行了方程拟合。结果表明,在整个试验期间,硫包衣尿素、树脂包膜尿素、植物油包膜尿素的养分累积释放率分别为51.01%、95.32%、82.91%,初期溶出率分别为4.89%、1.71%、2.07%,28 d养分累积释放率分别为36.30%、39.94%、43.33%。硫包衣尿素、树脂包膜尿素、植物油包膜尿素的养分累积释放率与土壤积温的关系均可用二项式方程进行拟合,且具有很好的相关性(相关系数r分别为0.940、0.998、0.984)。可根据各植胶区的施肥时期土壤积温,利用拟合方程计算出包膜尿素养分累积释放率,确定包膜尿素科学施肥措施,有利于包膜尿素在橡胶树上合理施用。

To explore the feasibility of the application of coated urea in the cultivation of rubber trees, the nutrient release characteristics of coated urea were studied in the rubber plantation soil with a buried bag experiment. Relationship between cumulative nitrogen release rate and accumulated temperature of soil was fitted by equations. Results showed that the nutrient accumulation-release rate of sulfur coated, resin coated, vegetable oil coated urea was 51.01%, 95.32% and 82.91%, respectively; the initial release rate was 4.89%, 1.71% and 2.07%, respectively; the cumulative nitrogen release rate of 28 d was 36.30%, 39.94%, 43.33%, respectively. Relationship between cumulative nitrogen release rate and accumulated temperature of soil was fitted by a quadratic equation, and the values of r were 0.940, 0.998, 0.984. Therefore, according to the soil accumulated temperature during the fertilization period, and the nitrogen cumulative release rate of coated urea was calculated using the fitting equation, to determine the scientific fertilization measures of the coated urea. It is helpful for the reasonable application of coated urea in rubber tree.