花碱土是淮阴地区分布最广的低产土壤,有405万亩,約占耕地面积1/4。这种砂质土壤耕层含有較多盐碱,返盐季节达0.2%以上;养分則很貧瘠,有机质在0.4~0.7%,氮素0.03~0.05%,全磷虽不少于千分之一,但有效态极为低微,不足0.001%。可見,盐碱的危害不是作物低产的唯一因素。实践証明,排盐抑碱和培肥是改良花碱土的有效途径。关于花碱土上施用化肥問題,群众一般 Alkali soil is the most widely distributed low-yielding soil in Huaiyin area, with 4.05 million mu, accounting for about 1/4 of cultivated land. This type of sandy soil contains more saline soil and more than 0.2% salt is returned to the salt season. Nutrients are very poor with 0.4-0.7% of organic matter and 0.03-0.05% of nitrogen. The total phosphorus is not less than one thousandth , But the effective state is very low, less than 0.001%. Can be seen that the harm of salt and alkali is not the only factor in low-yield crops. Practice has proved that salt and alkali and fertilizing salt is an effective way to improve the polluted alkaline soil. On the issue of chemical fertilizer on the spent soil, the general public