基于标准径流指数法的汾河上游水文干旱等级划分研究

Dividing Hydrologic Drought Degree of Upstream of Fenhe River Based on Standardized Runoff Index

以汾河上游为例,选取标准径流指数（SRI）为研究指标,分析上静游、汾河水库和兰村三座水文站1956～2000年实测年径流丰枯变化情况,基于SRI划分无旱、轻旱、中旱、重旱、特旱五个等级并获得了等级间的界限值,进而对汾河上游水文干旱等级进行了划分。结果表明,基于SRI的等级划分能够很好地反映汾河上游径流量的正偏性,在不同时间尺度下具有明显的一致性;中旱、重旱在汾河上游发生的概率较大,未来抗旱措施应主要集中在重旱区。

Taking the upstream of the Fenhe River for an example,this paper studied the standardized runoff index and analyzed the level of high and low runoff of the annual observed runoff data of three hydrometric stations（Shangjingyou,Fenhe reservoir and Lancun）from 1956 to 2000.Based on the SRI,it obtained the different values from excessive drought to drought-free for SRIindex.And then the grades of hydrological drought about the upstream of the Fenhe River was divided.The results show that the SRIhierarchies can well reflect the runoff features of the Fenhe River;it has obvious consistency in different time scales;the occurrence probability of moderate drought and heavy drought in the upstream of Fenhe River is higher;the future drought relief measures should be pay more attention to heavy drought.