表层岩溶带调蓄系数定量计算——以湘西洛塔赵家湾为例

Quantitative calculation of Regulating coefficient for epikarsk zone——Case study of Zhaojiawan, Luota, West of Hunan

本文以湖南洛塔赵家湾表层岩溶系统为例,综合利用水位、降雨量、蒸发量及泉流量等长观资料,分别对不同降雨特征下的表层岩溶带调蓄系数进行了定量计算,并对影响表层岩溶带调蓄能力的因素进行了分析。计算得到丰水期赵家湾表层岩溶带调蓄系数为0 14～0 2 8,明显小于枯水期调蓄系数0 44 ;但丰水期久旱后表层岩溶带的调蓄能力接近于枯水期;在丰水期,场雨和连续降雨时的调蓄能力比间歇降雨时的小近1倍。实例计算表明:赵家湾表层岩溶带具有一定的调蓄能力,其地下迳流滞后于降雨至少3d ,调蓄系数确实可以用来定量评价表层岩溶带的调蓄能力。

Zhaojiawan, a typical epikarst dynamic system monitoring site, is located in Luota, west of Hunan. The data, such as water level, precipitation, evaporation discharge, and spring discharge, have been obtained from the site. According to the data, regulating coefficients of Zhaojiawan epikarsk zone in varying rainfall conditions were calculated quantificationally, respectively. The range of regulating coefficients in rainy season is from 0.14 to 0.28, which is less than that in drought season obviously; and the regulating capability when the drought lasts a long time in rainy season is close to that in drought season. In rainy season, the regulating capability of epikarst zone during continuous rainfall is half of that in an intermittent rainfall. The quantitative calculation shows that the regulating capability of Zhaojiawan epikarst zone results in the delayed regiem of groundwater runoff 3 days later than rainfall, and the regulating coefficient can be used to evaluate the regulating capability of epikarst zone quantificationally.