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为保持和提高现有耕地的生产能力,本文从我县土壤肥力及肥料结构的演变,对在现代农业生产条件下耕地土壤的培肥进行分析.(一)土壤肥力的演变我县土壤类型有里下河地区的水稻上,长江三角洲潮土,少量滨海潮盐土.耕地土壤的肥力变化和人为影响密切相关.五六十年代全县开荒面积达15万亩,开荒后有机质矿化速度加快,含量急剧下降.水稻土地区逐步实行沤改旱、水旱轮作,打破了原来的有机质平衡;潮土地区质地较轻,早耕熟化使土壤有机质积累较少,原先有机质含量多的荒地含量急剧下降,光板地则有机质逐渐积累.1974年全县38个点土壤有机质平均含量由1959年的2.65%下降至1.74%,但与此同时速效养分有所增加,速效磷从2mg/kg
In order to maintain and improve the productivity of existing cultivated land, this paper analyzes the fertility of cultivated land under the conditions of modern agricultural production from the evolution of soil fertility and fertilizer structure in our county. (1) The evolution of soil fertility The types of soil in our county are Lixiahe area of rice, the Yangtze River Delta, a small amount of coastal tide salt soil.Cultivation of cultivated land fertility and human influence is closely related.Floating fifties and sixties the county wasteland area of 15 hectares, mineralization accelerated after the pioneers, The content of soil decreased sharply in the paddy soil area, and the drought, drought and drought rotation were gradually carried out in the paddy soil area, which broke the original balance of organic matter. The soil texture in the soil was light, and the accumulation of soil organic matter was less. , Light board to the gradual accumulation of organic matter in 1974 the county 38 points average soil organic matter decreased from 2.65% in 1959 to 1.74%, but at the same time available nutrients have increased, available phosphorus from 2mg / kg