| Based on the data of 6 meteorological observation station at the upstream and midstream of Heihe River from 1959 to 2009, the flow data of Heihe River 50 years, wheat and maize's growth data of 30 years in Zhangye, in order to investigate what influence will happen to the Crop planting structure, crop layout, process of growth period and yield at the climate warming, humidifying background conditions of agricultural climate changes and The change of hydrological characteristics. Research shows that: basin warming trend is obvious In recent 50 years Heihe, especially the upstream and midstream , the upstream at a rate of 0.53 ℃·10a-1, middle area is 0.35 ℃·10a-1; The heat condition improved markedly, Greater than 0℃of accumulated temperature of upstream, midstream and downstream reaches 151.1℃, 387.6℃, 247.3℃; The variation trend of precipitation over the middle area area is flat, the upstream area increased significantly in autumn and winter, up to 3.38 mm·10a-1 at the middle region and 13.87 mm·10a-1 upstream; Climate warming, humidifying is advantageous to the development of agricultural production, increased agricultural production potential; But the water, heat in different season, temporal and spatial difference is big, leading to Spring wheat, rice and other crops yield growth trend got slowly, The growth process got fast, puberty got shortly which was susceptible threated by the drought at spring and Late spring or early summer, the growth period Spring wheat has shortened four days than in the 1980s average in recent 10a, at the same time, the suitable area is reduced, quality decline; and which is at good quality and high economic benefit and thermophilic, such as maize and cotton, suitable area is expanding, The altitude of planting is improving, the Planting suitable ceiling height of late varieties of maize has Upgraded from an elevation of 1 500 m to about 1 800 m, crop growth period prolonged developmental duration, nearly 10 years of development period has been extended 13 days more than 80 years of last century, yield increasing obviously; Humid climate index fluctuates periodically change, A rising volatility trend was found in The mid 80's of last centuty, after this temperature increases faster than humidity in this basin, water and heat shows imbalance growth trend, which lead to the humid climate index declined slowly. As a result, mountain glaciers and snow melting speed, river water increase, water resource was consumpted excessively, which made huge influence to oasis agriculture sustainable development. |