论文部分内容阅读
土壤磷素在利用过程中,一般总是有消耗或者积累。所以,我国一些地区,已经出现了原来缺磷的土壤变得不缺磷,而原来不缺磷的土壤变得缺磷。这种消长情况,是什么因素决定的,有无可能进行概略的预测,这就是本文探讨的目的。 一、试验情况和方法 试验在浙江金华进行。土壤是第四纪红色粘土发育的高肥力水稻土。土壤的基本性质如下:pH 5.5,全氮0.19％,有机质3.53％,全P_2O_50.084％,有效P_2O_550 ppm,全K_2O 1.46％,缓效K_2O 18.2毫克/100克土,代换K_2O4.3毫克/100克土。 大田试验已进行了三年(1976～1978),仍在继续进行。前两年轮作是绿肥——双季稻,第三年为大麦——双季稻。试验处理为:O—O—O,三季均不施磷肥。P—O—O,三季中一季施磷肥。P—P—
Soil phosphorus in the use of the process, usually there is always consumption or accumulation. Therefore, in some areas of our country, it turns out that the original phosphorus-deficient soil has become deficient in phosphorus, while the soil that was not deficient in phosphorus has become phosphorus-deficient. This growth and decline is determined by what factors, the possibility of a rough forecast, which is the purpose of this paper. First, the test conditions and methods Test carried out in Jinhua, Zhejiang. Soil is a high-fertility paddy soil with Quaternary red clay development. The basic properties of soils were as follows: pH 5.5, total nitrogen 0.19%, organic matter 3.53%, total P 2 O 50.084%, effective P 2 O 550 ppm, total K 2 O 1.46%, slow K 2 O 18.2 mg / 100 g soil, K 2 O 4.3 mg / 100 grams of soil. Field trials have been conducted for three years (1976-1978) and are continuing. The first two years of rotation is green manure - double cropping rice, the third year of barley - double cropping rice. Test treatment: O-O-O, phosphate fertilizer are not applied in all three seasons. P-O-O, three quarters of a quarter of phosphate fertilizer. P-P-