论文部分内容阅读
上海全年平均气温为15.5℃,平均无霜期225～235天,日平均气温高于10℃的作物生长期,平均有233天,高于15℃的喜温作物生长期也有186天左右。4～9月平均各月雨量都在 100mm以上,光照在150小时以上。目前上海粮食生产的主要栽培形式是一年三熟,往往由于气侯条件的变异,产量有丰欠之别。主要问题是有效生长期受限,一年安排三熟作物季节紧,后季稻遇上秋季低温危害,影响稳产高产。尽管防御秋季低
In Shanghai, the annual average temperature is 15.5 ℃, the average frost-free period is 225-235 days, and the average daily temperature is higher than 10 ℃ in crop growth period, with an average of 233 days. The growth stage of hi-temperature crop above 15 ℃ is also about 186 days. From April to September, the average monthly rainfall was more than 100mm and the light was above 150 hours. At present, the main cultivation form of grain production in Shanghai is three crops a year, often due to variations in climate conditions. The main problem is the limited effective growth period, one-year arrangement of three-season crop tight, late autumn rice crop encounter low-temperature damage, affecting stable and high yield. Despite the low defensive autumn