气候变暖对河西走廊中部农业的影响

Influence of Climate Warming on Agriculture in the Middle of Hexi Corridor

选取河西走廊中部张掖市6县（区）1961～2006年日平均气温、日最低气温、年降水资料。计算历年各地气温、积温、无霜冻期和农业气候生产力，分析河西走廊中部气候变暖对农业生产的影响。结果表明：20世纪80年代末期以来，河西走廊中部气温呈持续升高趋势，1987～2006年的平均气温明显增高，且冬季升温幅度最为显著，秋季次之，春、夏季升温幅度较小；≥0℃和≥10℃积温增多，无霜冻期延长，气候生产力增加。80年代后期气候明显变暖，喜温作物面积扩大，复种指数提高，有利于冬季大棚蔬菜等设施农业的生产；干旱发生频率加大，病虫越冬存活率上升，导致农业生产成本增加。

Based on the daily mean air temperature, the daily minimum air temperature and annual precipitation data from six counties （district） in the middle part of the Hexi Corridor during 1961 -2006, the accumulative temperature, no frost period and the agriculture climate productivities are calculated in each area, and the influence of climate warming on agriculture is analyzed. Results show that the air temperature presented increasing trend since the 1980s, and the average temperature during 1987 -2006 increased obviously. Due to the accumulative temperatures （ ≥0 ℃ and ≥ 10 ℃ ） increase and the frost -free season prolongation, the climate productivity increased also. Obvious climate warming made the thermophilic crop area enlarge and multiple crop index improve, and it is benefit to winter vegetables in greenhouses. Meanwhile, drought occurred frequently and the survival rate of disease - pest living through the winter rose, which led to the cost of agriculture production increase.