基于模糊综合干旱指数的黄河源区作物生长季干旱时空分布分析

Drought temporospatial distributions of crop growth season in source region of Yellow River based on fuzzy comprehensive drought index

依据黄河源区28个气象站点的逐月气象资料,运用模糊综合法建立了源区综合干旱指数,从而较为全面地分析了黄河上游源区作物生长季干旱时空分布特征.结果表明:黄河源区大部分地区轻中干旱发生频繁,且发生频率高于重特干旱.流域内春旱最为严重,夏秋干旱次之.生长季重特干旱在西部高海拔寒冷地区发生频率低,在半牧业半农业地区发生频率相对较高.1960-2013黄河上游源区干旱主要经历了4个时期,主振荡周期为28a.黄河源区干湿突变年为1982年和2000年.结合历史实情,基于模糊综合法建立的综合干旱指数,监测结果与历史实情吻合,适宜用于黄河源区干旱监测,能够较科学地反映源区干旱情形.

A comprehensive drought evaluation index of the source region of Yellow River is established by fuzzy comprehensive decision process on basis of climatic data from 28 weather stations. The temporospatial distributions of drought in the area are analyzed. The results show that the light drought and medium drought situations occur frequently in source region of the Yellow River than heavy drought. Spring drought in this region happened more frequently than summer and fall drought. The frequency of heavy drought in crop gross season is low in the western high altitude cold regions as drought occur frequently in agriculture half pastoral area animal husbandry. The drought time （1960-2013） in the basin was divided into 4 different periods. The main oscillation period is 28 a. There existed obvious abrupt change of dry and wet in 1982 and 2000. Combined with historical facts, it is shown that the comprehensive drought evaluation index is suitable for the Yellow River source region drought monitoring and it can reflect the scientific source region drought situation.