千岛湖水体稳定度和热分层结构对溶解氧垂向分布的影响
Effects of water stability and thermal stratification on the vertical distribution of dissolved oxygen at Lake Qiandao
张如枫 1兰佳 2王裕成 2满小明 3吴松涛 4吴志旭 2李慧赟 5罗潋葱 6李加龙 1龚发露 6殷鑫星 6孙婷6
作者信息
- 1. 云南大学国际河流与生态安全研究院, 昆明 650500
- 2. 杭州市生态环境局淳安分局, 杭州 311700
- 3. 普天信息技术有限公司, 北京 100086
- 4. 浦江县气象局, 金华 322200
- 5. 中国科学院南京地理与湖泊研究所, 南京 210008
- 6. 云南大学生态与环境学院高原湖泊生态与治理研究院, 昆明 650500
- 折叠
摘要
基于 2017 年 1 月—2020 年 2 月千岛湖大坝前水质高频监测数据与湖心区气象数据,使用Lake Analyzer(LA)软件计算了水体稳定度指标("施密特稳定度"和"浮力频率")和热分层指标("温跃层深度"和"温跃层厚度"),并与溶解氧垂向分布指标("氧跃层深度"和"氧跃层强度")结合分析.结果表明千岛湖存在时间长且稳定的热力分层和溶解氧分层,分层期为每年 4-12 月,根据结构变化可分为形成期(4-6 月)、稳定期(7-9 月)和减弱期(10-12 月)三个阶段.水体稳定度指标、热分层指标和溶解氧垂向分布指标间相关分析结果表明:水体混合状态是影响溶解氧垂向分布的重要因素,湖体存在热分层则是氧跃层出现的根本原因,水体稳定度升高与热分层结构形成均阻碍溶解氧的垂向交换,促进氧跃层的形成.基于回归分析,发现温跃层深度与氧跃层深度具有良好的线性关系,拟合精度高(R2=0.81,N=25),说明在千岛湖可通过温跃层深度推断氧跃层态势.研究结果同时证明 LA 在千岛湖的可适用性,以及在其它湖泊的可推广性,提供了水体稳定度和热分层指标定量化计算的工具.
Abstract
To provide substantial information of vertical distribution of dissolved oxygen(DO)at Lake Qiandao,oxycline depth(OD)and oxycline intensity(OI)were defined and calculated for January 2017 to February 2020.Lake Analyzer(LA)was used to calculate Schmidt Stability(St),Buoyancy frequency(N2),thermocline depth(thermD)and thermocline thickness(thermT)based on the high-frequency monitoring water quality(WQ)data and the meteorological data at Lake Qiandao for the same period.The results demonstrated that there were long-lasting thermal stratification and DO stratification from April to December through the year.Thermal stratifications showed obvious seasonality with stratifications initially formed during April-June,strengthened during July-September,and weakened during October-December.According to Spearman correlation analysis among the parameters for water stability,thermal stratification and vertical DO distribution,water stability was a key factor for vertical DO distribution,and the thermal stratification was a key factor for oxycline formation.Intensive thermal stratification decreased vertical DO exchange between the upper and lower layers,and promoted the oxycline formation.ThermD and OD was closely correlated with R2 of 0.81(N=25).Successful application of LA to Lake Qiandao showed that LA was a reliable and adaptive tool for quantitatively estimating the parameters for thermal and oxycline stratifications and water stability not only for Lake Qiandao but also for other lakes.
关键词
水体稳定度/热分层/溶解氧/氧跃层/Lake/Analyzer/千岛湖Key words
water stability/thermal stratification/dissolved oxygen/oxycline/Lake Analyzer/Lake Qiandao引用本文复制引用
基金项目
云南大学人才引进启动项目(C176220100043)
国家自然科学基金(NSFC-41671205)
出版年
2024
国家科技期刊平台
NSTL
万方数据