基于生态水文指标的陈村水库日调节水流影响分析

Impact of Daily Regulation of Chencun Reservoir on Flow Regime Based on Ecohydrological Indexes

水利工程日调节作用下河流日内水位、流量陡涨陡落,产生水流脉冲,导致河流生境条件与天然状况下迥异,可对河流生态系统健康造成影响。基于安徽省第一大水库陈村水库上下游水文站逐时水位资料,应用水流脉冲频率、历时、大小等生态水文评价指标对陈村水库的日调节影响进行逐月评价,获得了水库下游不同调峰流量、不同调峰历时的水流脉冲的各月分布特征。评价结果可定量反映水库日调节作用下泄非恒定流的水流特征以及河岸水陆生态交错带的淹没频率、历时及范围等年内分布特征。

Hydropower station’s daily regulation may cause rapid water level flow fluctuations and produce daily flow pulses. Such daily flow fluctuation create highly unnatural river habitat characteristics and health of river ecosystems could be degraded. Based on the time series of hourly water level data measured at hydrological stations upstream and downstream of Chencun Reservoir, ecohydrological indices in terms of magnitude, duration, and frequency depicting flow pulses were applied to evaluate the hydrological variations impacted by Chencun hydropower station’s daily regulation for each month. The evaluation results show the monthly distribution of flow pulses with different peaking flow magnitude and different duration of peaking flow, which could disclose characteristics of the unsteady flow. Monthly distribution of inundation frequency, duration and range of the littoral zone along the river bank could also be inferred from the results.