滇池湖滨带设施蔬菜、花卉的农田养分平衡*

 农田养分平衡状况一方面从根本上决定着土壤肥力的发展方向,另一方面,影响人类的生活环境。主要针对滇池湖滨带设施蔬菜、花卉的施肥情况,对各种蔬菜、花卉以及不同的轮作方式的施肥量和农田养分平衡进行了分析。结果表明：花卉的肥料施用量总体高于蔬菜的施用量,类内均值为1584kg(N)/hm²,787kg(P₂O₅)/ hm²,1580kg(K₂O) / hm²,蔬菜的类内均值为396kg(N)/ hm²,156kg(P₂O₅)/ hm²,144kg(K₂O)/ hm²;在蔬菜中,绿叶菜类的施用量高于其他菜类;蔬菜、花卉氮、磷盈余量较大,约45%的作物钾处于亏缺状态;蔬菜中各类内养分盈余由高到低排列顺序为：绿叶类＞豆类＞白菜类＞甘蓝类＞茄果类＞瓜类,根菜类的氮、钾养分处于亏缺状态。在本试验研究条件下,大部分轮作方式的农田养分处于盈余状态,特别是氮、钾养分。

The Nutrient Balance in the Protected Fields of Vegetable and Flower Cultivation in Dian Lakefront

The nutrient balance of agroecosystem is the result of a complicated dynamic process, which determines soil fertility and affects environment. The fertilizer input and nutrient balance in protected fields of vegetable and flower cultivation in Dian lackfront were analyzed in this study. The result showed that the average rates of N,P and K fertilizer application in flower cultivation are 1584kg(N)/ hm², 787kg(P₂O₅)/ hm² and 1580kg (K₂O)/ hm² respectively,which were generally higher than those applied in vegetable cultivation. In the latter case, average N,P and K fertilizer rates applied were 396kg(N)/ hm²,156kg(P₂O₅)/ hm² and 144kg(K₂O)/ hm² respectively．Among different types of vegetable, green leave vegetable was applied with highest rate of fertilizer. In general, N and P were surplus, while 45% crops are short in K supply. In this experiment, most models of crop rotation are surplus in nutrient supply, especially N and K.