摘要
为掌握水库热分层与氢氧同位素空间分布的关系,研究了广西兴安县五里峡水库夏季氢氧同位素空间分布特征及影响因素。研究表明:1五里峡水库夏季出现明显的热分层,库表层至-5 m为表水层,-5 m至-20 m为温跃层,-20 m以下为底温层;2五里峡水库δ^(18)O、δD值沿大气降水线分布,但均落在桂林市大气降水线右下方,其线性方程为δD=4.66δ^(18)O-10.85(R2=0.76),其斜率与全球大气降雨线(GMWL)和桂林市降雨线(CLMWL)的斜率和截距差异明显,表明五里峡水库主要由降水补给,但在补给五里峡水库前已经过了强烈的蒸发作用和水岩作用;3δ^(18)O、δD随水深的增加逐渐偏负,具有表水层>入库水体>温跃层>底温层>出库水体(>表示偏正)的垂向分布特征。分析认为入库水体氢氧同位素的季节变化和蒸发作用随深度增加而降低是五里峡水库夏季分层期间水体氢氧同位素垂向变化的主要影响因素。
To examine the relationship between thermal stratification and spatial distribution of hydrogen and oxygen isotope in Wulixia Reservoir,Guangxi,spatial characteristics and factors influencing hydrogen and oxygen isotopes were studied in during the summer of 2014. Results showed that 1 Wulixia Reservoir showed obvious thermal stratification in 2014 summer which can be divided into three layers,epilimnion（ from surface water to a depth of 5 m）,thermocline（ depths of from 5 m to 20 m） and hypolimnion（ below 20 m）; 2 All the δ^（18）O and δD values of Wulixia Reservoir（ line equation： δD = 4. 66δ^（18）O-10. 85,R2= 0. 76） scattered roughly along Global Meteorological Water Line（ GMWL）,which showed the reservoir water to originate from modern meteorological precipitation. However,water δ^（18）O and δD of Wulixia Reservoir,located in the right lower area of the Guilin Local Meteorological Water Line（ CLMWL） and the slope of their line equation were obviously different from the slope of GMWL and CLMWL line,which indicate that evaporation and water-rock interaction could occur before water entered the reservoir; 3 δ^（18）O andδD values of water generally decreased as depth increased,in the following order epilimnion 〉inflow water〉 thermocline 〉hypolimnion outflow water（ here＂〉 ＂means＂more positive＂）. Results indicate that seasonal variation of inflow water δ^（18）O and δD and water evaporation decreased as water depth increased. These are the two primary factors influencing and controlling the vertical distribution of δ^（18）O and δD in Wulixia Reservoir during the thermal stratification that takes place during summer.
出处
《水科学进展》
EI
CAS
CSCD
北大核心
2016年第4期561-568,共8页
Advances in Water Science
基金
国家自然科学基金资助项目(41572234)
国土资源部公益性行业科研专项经费资助项目(201311148)~~
关键词
热分层效应
氢氧同位素
空间分布
影响因素
水库
thermal stratification
hydrogen and oxygen isotopes
spatial distribution
influence factors
reservoir
