福建柑桔园营养施肥状况及其施肥改进建议

Study on the Rational Fertilizing in the Citrus Orchards in Fujian Province by Nutritional Diagnosis

以福建省永春等10县（市）70片（≥3．5hm2）柑桔示范园为代表，通过土壤、叶片分析及施肥状况的综合诊断得出的结果表明：84％的示范园土壤显著酸化（pH＜5．5），主要是施用N、P、K化肥造成的；营养失调也普遍存在于示范围中，其中主要元素缺Ca、P吸收障碍及微量元素B、Cu的过量尤为普遍；施肥中有机肥不足，P、N肥滥用，Ca、Mg、K肥欠缺；叶片K、Mg并不简单受其土壤有效成分的影响，叶片K与土壤"全N／有效K"、"水解N／有效K"，叶片Mg与土壤"代换Mg／代换Ca"呈极显著相关（P＜0．01，r=-0．36、-0．39、0．49）。据此，对以红壤为主要土壤类型的福建柑桔产区的施肥提出了改进建议。

The soil and leaf nutrients and fertilizing status of 70 citrus orchards (≥3. 5hm2)in Yongchun and other 9 countries of Fujian were analyzed. Results showed the pH of 84% orchards soil was lower than 5. 5; the phenomenon of nutritional disorder appeared commonly in the orchards,of which the deficiency of Ca,and the retardation of P absorption,and the overabsorption of microelements B and Cu were particularly common. As to fertilizers,besides the shortage of organic fertilizers,there were over fertilized of P and N,and deficiency of Ca,Mg and K. The K and Mg levels in the leaf were affected by available components in soil,moreover,K level in the leaf was extremely significantly correlated to total N/available K and hydrolyzable N/available K,and so was Mg in the leaf to exchangeable Mg/exchangeable Ca in soils (P＜0.01,r=-0. 36,-0. 39,0.49). The improvement of fertilizing was recommended.