四川升钟水库1983—2011年降水变化特征分析

A Study of Precipitation Variation Characteristics of Shengzhong Reservoir from 1983 to 2011

降水是反映区域气候变化的重要指标之一,升钟水库是嘉陵江流域最大的人工水库,研究该区的降水变化特征对拟定合理的蓄调水计划、有效开发和保护升钟水库的水环境资源意义重大。本研究基于1983—2011年升钟水库的月降水资料,采用集中度、集中期指标分析了降水的年内分配特征,采用Mann-Kendall和小波分析对四季及年降水变化趋势、突变特征和周期特性进行了分析。结果表明:1)1983—2011年间升钟水库降水量均主要集中在6—7月,但在观测期间降水的年内分配有均衡化趋势;2)1983—2011年间升钟水库降水量总体以9.786mm/a的速率增加;3)升钟水库降水量在季节和年际尺度上均大致以14a为第一主周期,以9a为第二主周期,以5a为第三主周期。因此,在开发和利用升钟水库水资源的过程中应遵循该区降水变化规律,因时制宜地进行水资源利用和调节,提高水资源的利用效率。

Precipitation is an important index that reflects regional climate change.As the largest artificial reservoir in Jialing river basin,a study on the precipitation variation characteristics of Shengzhong reservoir is of great significance to formulate reasonable water storage and divert plans,develop and protect its water environment resources in an effective way.Based on the monthly precipitation data from 1983 to 2011,its annual distribution characteristics of precipitation are analyzed by precipitation concentration degree and precipitation concentration period,and its annual variation trend,abrupt change characteristics and periodic characteristics in four seasons are explored by Mann-Kendal and wavelet analysis.The results indicate:(1) the precipitation concentration period of Shengzhong Reservoir was between June and July from 1983 to 2011,but the annual distribution of precipitation during the observation period had shown an equilibrium trend;(2) the precipitation of Shengzhong Reservoir had generally increased with a speed of 9.786 mm/a from 1983 to 2011;(3) in terms of season and inter-annual time scale,the first principal period of precipitation was 14a,and the second,the third ones were respectively 9a and 5a.Therefore,it is essential to follow the precipitation change rule in the process of developing and regulating water resources of Shengzhong reservoir according to the circumstances so as to improve the utilization efficiency.