潴育性稻田肥料效应函数应用研究

AN APPLICATION STUDY OF FERTILIZER RESPONSE FUNCTIONS FOR HYDRAGRIC PADDY SOILS

对东洞庭湖区不同母质发育的潴育性稻田肥料效应的研究表明，水稻的施肥效应宜用二次多项式模型表示。由相同母质发育的、肥力差异不大的稻田，其肥料效应方程式可通过汇总，求得其近似的、运用范围较广的一般通式。氮、磷、钾三要素中，氮肥的增产效果最大，磷、钾肥则较小，且磷肥的效果仅表现在早稻，钾肥的效果主要表现在晚稻。氦肥的最佳经济施用量与土壤碱解氮含量及地力产量均呈极显著负相关；磷、钾肥的经济最佳施用量分别与稻田的速效磷、钾含量呈极显著负相关；稻田的地力产量与施肥产量之间亦呈极显著负相关。

A study of hydragric paddy soils developed from various parent materials in the east area ofDongting Lake showed that the fertilizing response of rice fitted well to a quadratic multinomicalmodel. With the help of the computer,a general fertilizer response quadratic multinomical modelwas obtained for rice fields developed from the same parent material and having similar fertility. Ofthe three fertilizers of N,Pand K,N exhibited the greatest effect on yield increase. Early seasonrice responded moderately to P fertillzation while K had a moderate effect on late season rice crop.The optimum cost-efficient N rate showed a highly significant negative correlation with the alkali-hydrolyzable N in the soil and the productivity of the soil.The optimum cost-efficient rate of Pand K was negatively correlated with the readily available P and K in the soil,respectjvely.Asignificant negative correlation was also observed between the yield of the riCe field without fertillzerapplication and the yield with fertilizer addition.