气候暖干化对甘肃省谷子产量的影响及对策

Effects of climate warming and drying on millet yield in Gansu Province and related countermeasures

基于甘肃省甘州(河西温和干旱绿洲灌溉区)、安定(陇中温和半干旱旱作区)、西峰(陇东温和半湿润旱作区)气温、降水和谷子产量资料,计算出各区域谷子生育期内≥0℃、≥5℃、≥10℃、≥15℃、≥20℃活动积温以及生育关键期平均气温和降水量,用正交多项式拟合分离出谷子气候产量,并采用线性倾向、累积距平、Mann-Kendall法分析研究区气候和谷子气候产量的变化特征,以及气候变化对谷子产量的影响.结果表明:气候暖干化是甘肃各区域现代气候变化的主要特征,各地气温从20世纪90年代初开始呈显著上升趋势,降水从20世纪80年代后期开始显著减少;该区谷子产量与温度、降水量呈显著相关关系,旱作区谷子产量随生育关键期内气温增高、降水量增多而提高,河西走廊绿洲灌区谷子产量随气温增高而提高;气候暖干化严重影响谷子产量,西峰、安定、甘州谷子产量的气象波动指数分别占实际产量变异系数的73%、72%和54%,变暖后(1993—2008年)较变暖前(1985—1992年)所占百分率明显增大;气候变暖有利于谷子产量增加,与气候变暖前相比,气候变暖后西峰、安定、甘州谷子年均气候产量的增加量分别为30.6、43.1和121.1kg·hm-2.针对甘肃省未来气候继续暖干化的趋势,应进一步扩大谷子种植面积、调整谷子种植结构,同时,要根据不同气候类型区域、不同气候年型选种不同特性的品种,采取不同的种植措施.

Based on the data of air temperature,precipitation,and millet yield from Ganzhou,Anding,and Xifeng,the representative stations in Hexi moderate arid oasis irrigation area,moderate sub-arid dry area in middle Gansu,and moderate sub-humid dry area in eastern Gansu,respectively,this paper calculated the regional active accumulated temperature of ≥0 ℃,≥5 ℃,≥10 ℃,≥15 ℃,and ≥20 ℃ in millet growth period,and the average temperature and precipitation in millet key growth stages.The millet climatic yield was isolated by orthogonal polynomial,and the change characteristics of climate and millet climatic yield as well as the effects of climate change on millet yield were analyzed by statistical methods of linear tendency,cumulative anomaly,and Mann-Kendall.The results showed that warming and drying were the main regional features in the modern climatic change of Gansu.The regional temperature had a significant upward trend since the early 1990s,while the precipitation was significantly reduced from the late 1980s.There were significant correlations between millet yield and climatic factors.The millet yield in dry areas increased with the increasing temperature and precipitation in millet key growth stages,and that in Hexi Corridor area increased with increasing temperature.Warming and drying affected millet yield prominently.The weather fluctuation index of regional millet yield in Xifeng,Anding,and Ganzhou accounted for 73%,72%,and 54% of real output coefficient variation,respectively,and the percentages increased significantly after warming.Warming was conducive to the increase of millet production,and the annual increment of millet climatic yield in Xifeng,Anding,and Ganzhou after warming was 30.6,43.1,and 121.1 kg·hm-2,respectively.Aiming at the warming and drying trend in Gansu Province in the future,the millet planting area in the Province should be further expanded,and the millet planting structure should be adjusted.At the same time,according to the different regional and yearly climatic types,different varieties should be selected,and various planting measures should be taken.