棕红壤上几种磷矿粉肥不同施用量的效果及经济效益

Rosponse and economic benefit of several kinds of phosphate rock with various amounts applied to red brown soil

在棕红壤上对６季作物施用几种磷肥的田间试验结果表明，施用磷矿粉和重过磷酸钙与对照比较，３季油菜籽增产３．６～６．６倍，夏作物大豆、花生增产甚微。重过磷酸钙与磷矿粉的１５，２５，３５ｍｇ（Ｐ）／ｋｇ用量比较，对第一、二季油菜的增产效果，两种磷肥肥效相当，但第三季油菜，磷矿粉肥优于重过磷酸钙。６季作物的产、投比和磷素的利用率以１５ｍｇ（Ｐ）／ｋｇ磷水平最佳，但施磷经济效益以２５ｍｇ（ｐ）／ｋｇ磷水平较高。磷素累积利用率为４２％～８８％。

A three years field testing of several kinds of phosphate rock(PR) applied tored brown soil was investigated. The results showed that for the treatments of PR and treblesuperphosphate(TSP) applied , the yield of rapeseed in three years was 3.6～6.6 times high- er than that for the treatments of CK. The yield of summer crops ,like soybean and peanut,was little increased for the treatments of phosphate fertilizers applied. For various amountsphosphate fertilizers applied ,the response to PRs and TSP was almost same for the yield ofrapeseed in the first and the second year ,but in the third year , the response to PRs was bet-ter than that to TSP. Among three levels of phosphate fertilizers applied, the best one wasthe level of 15mg(P)/kg with the high rate of output to input and the high utilized coefficientof phosphorous for three years. It was considered that the level of 25mg(P)/kg was withhigh economic benefit,of which the utilized coefficient of phosphorous was 42%～88%。