论文部分内容阅读
张掖地区属内陆沙漠性气候,降水稀少,蒸发量大,气候干燥,农作物依赖祁连山冰雪融化灌溉。由于冰雪融化是随着气温的高低而变化。春末夏初气温低,冰雪融化缓慢,河流来水量少,小麦苗期用水十分紧张。六月以后气温增高,水量随之加大,灌溉上往往出现大定额,多次数,“水从门前过,不浇瘾不过”的不合理灌溉方法,造成小麦徒长倒伏,贪青晚熟,热秕减产。一九七八年是全区历史上少有的干旱年,大旱持续一百五十多天。五、六月份河水流量比历年同期减少46%8—50.3%,雨量少六成,小麦比往年少灌一至二个水,但
Zhangye area belongs to an inland desert climate with rare precipitation, large amount of evaporation and dry climate. The crops depend on the melting of snow and ice in the Qilian Mountains. As the ice and snow melt with the temperature changes. Early spring and early summer temperatures are low, the snow melts slowly, less water flow into the river, wheat seedling water is very tense. After June, the temperature will increase and the amount of water will increase. There will always be large quotas and multiple times on irrigation. Irrational irrigation methods such as “no water from the door”秕 cut production. One of the few dry years in the history of the whole region in 1978, the severe drought lasted for more than 150 days. 5. The flow of rivers in June and June decreased by 46% 8-50.3% over the same period of the previous year with a rainfall of 60% less than that of the previous year. However, wheat weighed one to two less water than in previous years