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一、棉地越种越瘦瑞昌是赣北棉区的主要产棉县之一。全县植棉面积共八万五千亩,占耕地总面积的30％。土壤的主要类型包括:河、湖积冲积相潮土、下属系黄土发育的马肝土、泥质岩类风化物和第四纪红粘土形成的红壤和碳酸盐岩类风化物形成的棕灰土、红灰土等。其中红壤面积约占30％,其余各类土壤大约各占15～20％。这些棉地,大部份都有二、三十年植棉历史。从目前情况看,除沿江滨湖和城乡居民点附近的一部份较肥棉地外,剩下约有60～70％的棉地,都程度不同地出现了肥力下降的现象。主要表现:一是有机质含
First, the more cotton the more thin Ruichang is one of the major cotton counties in northern Jiangxi cotton area. The county cotton area of 85,000 acres, accounting for 30% of the total area of cultivated land. The main types of soil include: alluvial-fluvial alluvial soil of the river and lacustrine, brown soil of red soil and carbonate rock weathering formed by the loamy loamy soil, argillaceous weathered materials and Quaternary red clay Lime soil, red soil and so on. Red soil area accounts for about 30% of the remaining types of soil about 15 to 20% each. Most of these cotton fields have two or three decades of cotton-growing history. Judging from the current situation, in addition to some relatively fat cotton land along the riverside lakes and urban and rural residential areas, the remaining about 60 to 70% of the cotton fields, all have varying degrees of decline in fertility. The main performance: First, organic matter