江苏苏北沿海稻区 ,土壤属于由滩涂成长起来的水稻土 ,种稻初起以单一的莎草科杂草为优势种群 ,随着水稻种植年限的延长以及化除技术的应用 ,稻田杂草种群发生演变 ,莎草密度下降 ,稗草上升 ,到 90年代中、后期 ,阔叶杂草异军突起 ,成为移栽稻田密度最高的杂草种类 ,其中又以耳 Soil in the northern coastal Jiangsu province of Jiangsu Province belongs to the paddy soil that grew up by tidal flats. The single dominant family of sedge weed was the dominant species in the early rice growing stage. With the extension of rice planting years and the application of chemical removal techniques, Population evolution, sedge density decreased, barnyard grass rose to the mid-90s, late, broad-leaved weeds a sudden emergence, becoming the highest density of transplanted paddy weed species, which in turn ear