含磷土是一种含磷品位低(一般在0.5～5%)的磷矿土。用含磷土直接压地,过圈做底肥,拌人粪尿或氨水做口肥,增产效果均在5～20%。凤城县大卜公社的经验证明,就地取材,积极开发利用含磷土,是增辟肥沅,改良土壤,提高粮食单产的一个新途径。1975年以来,大卜公社根据土壤普查发现全社土壤缺磷、少氮、钾有余的特点,学习外地普查磷矿和施用含磷土的经验, Phosphorus is a phosphorus-bearing soil with low grade (generally 0.5 to 5%) of phosphate rock. Direct pressure with phosphorus-bearing soil, the circle made of base fertilizer, mixed with human waste water or ammonia to make fat, increase the production of 5 to 20%. The experience of Fengcheng Dabu Commune has proved that using local materials and actively developing and utilizing phosphorus-bearing soils is a new way to increase fertility, improve soil and increase grain yield. Since 1975, according to the Census of Dabu soil found throughout the community phosphorus, nitrogen and potassium less than the characteristics of clues to learn from the census and the experience of phosphorus-containing soil,