渭北东部旱塬氮磷水三因素交互作用与耦合模型研究

STUDY ON INTERACTION FOR N,P AND WATER AND THEIR COUPLED MODEL IN EAST PART OF WEIBEI DRYLAND

在旱棚控制条件下，用三因素五水平回归设计，研究了渭北东部旱塬氮磷水三因素的交互作用及耦合模型，结果表明：①氮、磷、水对冬小麦的增产顺序为水＞氮＞磷；②氮磷和氮水的交互作用为协同作用型，氮、磷、水都为李比希限制因素；磷、水交互作用为拮抗型，磷、水为拮抗限制因素；当氮、磷、水同时投入时，磷水拮抗型转变为协同作用型，磷、水也变为李比希限制因素；③水分对目标产量的校正模型为：ｙ＝－３０．６５２±０．９９６６Ｗ＿Ｂ，ｙ＝－１６．５０２＋０．８７５Ｗ＿Ｒ，ｙ＝－１１３．２９７５＋０．６０４１Ｗ＿Ｔ；④水分对施肥量的校正模型为：Ｘ＿１（Ｎ）＝０．７９５６＋０．４７２８Ｘ＿３，Ｘ＿２（Ｐ＿２Ｏ＿５）＝０．４６７９＋０．２１６９Ｘ＿３。

This study was carried out by using regression design with N,P and water three factorsand five levels under the greenhouse in Heyang county.The results show :①The yield re-sponses of winter wheat to the three factors were in order of water>N>P.②The interactionfor three factors was verv remarkable.The interaction between N and P or between N andwater were synergistic type and the three factors were Liebig types of limitation. But the in-teraction between P and water was antagonism and the two factors were antagonistic types oflimitation,However,when N,P and water three factors were applied simultaneously,the in-teraction between P and water was changed form antagonism to synergism and the two fac-tors were also changed to Liebig limitation factors. ③The calibration models of water forobjective yield of winter wheat were:y=-30.652+0.9966W_R,y=-16.502+0.875W_R,y=-113.2975+0.6041W_r,④The calibration models of water for recommendation of fertilizerrate were:X_1(N)=0.7956+0.4728X_3,X_2(P_2O_5)=0.4679+0.2169X_3.