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上海郊区地处长江三角洲南侧,属于亚热带季风气候区,气候温和,雨量充沛,是由长江冲积母质和湖泊沉积母质在稻、麦、棉、油、绿肥等农作物轮作下发育起来的高产水稻土。六十年代以来,农田耕作制度有了很大变革。随着土壤淹水时间的延长,湿耕机会增多,土壤结构易遭破坏,耕性变劣,犁底层在湿耕辗压之下变得愈加密实,同时由于手扶拖拉机的连年浅耕,有犁底层上升和变厚的趋势,导致水份难以下渗,水、气矛盾日益突出,
The suburb of Shanghai is located in the south of the Yangtze River Delta. It belongs to the subtropical monsoon climate zone with a mild climate and abundant rainfall. It is a high-yielding paddy developed by the alluvial parent material of the Yangtze River and the sedimentary parent material of lakes under crops such as rice, wheat, cotton, oil and green manure. Since the 1960s, farmland farming system has undergone great changes. With the prolongation of flooding time, opportunities for wet tillage increased, the soil structure was easily damaged, the tillage became worse, and the bottom layer of plow became more compact under wet tillage. At the same time, Plow the bottom of the rising and thickening of the trend, leading to difficult to infiltrate water, water and gas conflicts have become increasingly prominent,