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上海郊区是全国粮棉单产较高的地区之一,但产量高而不稳,年际波动幅度很大。1965～1981年粮食常年亩产平均1286.6±190.4斤,变异系数达15％,其中尤以后季稻的稳产性为差,1978年亩产732斤,1980年仅362斤,两者相差一倍。棉花1964～1981年平均亩产皮棉117±22斤,变异系数达19％,1978年平均亩产169斤,1981年仅84斤,低产年只及高产年的一半。即使在同一年份,各县、社之间的产量差距也十分悬殊。粮棉产量不稳的原因很多,有灾害
The suburbs of Shanghai are one of the regions where the yield of grain and cotton in the whole country is relatively high, but the output is high and unstable, and the annual fluctuation is very large. From 1965 to 1981, perennial grain yield averaged 1286.6 ± 190.4 kg, with a coefficient of variation of 15%. Especially in the latter part of the year, the stable yield of rice was poor, with 732 kg per mu in 1978 and 362 kg in 1980, the difference between the two was double. The average yield of cotton was 117 ± 22 pounds per mu in 1964-1981 with a coefficient of variation of 19%. In 1978, the average yield per mu was 169 kilograms, only 84 kilograms in 1981, while the low-yielding year was only half that of the high-yielding year. Even in the same year, the output gap between counties and communities is also very poor. There are many reasons for the instability of grain and cotton production and disaster