论文部分内容阅读
河南省南阳地区在五十年代建成的鸭河灌区,约有二百余万亩,其中四分之三以上是低洼易涝区和“上浸地”(即耕作层以下为黄粘土夹杂着姜石的难透水层,雨后耕作层长期为水饱和)。南阳地区属于南北过渡地带的江淮流域气候,年雨量为800—1100毫米,雨季集中在秋作物生长季节,即6—9月,年平均气温为14—15℃,大于10℃的活动积温为4802℃,无霜期
About 500,000 mu of Duhe Irrigation District was built in Nanyang area of Henan Province in the 1950s, of which more than three-fourths were low-lying flood-prone areas and “flooded land” (ie, the yellow clay below the tillage layer was mixed with ginger Permeable layer of stone, tillage after rain for a long period of water saturation). Nanyang belongs to the north-south transitional zone of the Yangtze River and Huaihe River Basin climate, annual rainfall 800-1100 mm, the rainy season concentrated in the autumn crop growing season, that is, from June to September, the annual average temperature of 14-15 ℃, greater than 10 ℃ activity accumulated temperature of 4802 ℃, frost-free period