【摘要】 为了解喀斯特高原水库回水区丰枯水期水体二氧化碳分压变化规律及二氧化碳扩散通量特征,本文以云贵高原喀斯特水库——万峰湖为例,于2016年9月和2017年2月对该水库回水区水体表层进行走航监测和采样,利用水质参数仪现场测定水体参数,其余水体参数于实验室做进一步测定分析,pCO₂通过水化学平衡原理和亨利定律计算得到.结果表明,丰水期回水区表层pCO₂变化范围为124.84—374.06 Pa,均值为219.580 Pa;枯水期回水区表层pCO₂变化范围为210.19—371.53 Pa,均值为290.607 Pa,丰水期pCO₂值小于枯水期.相关性分析得出,枯水期pCO₂与T（温度）呈负相关,且pCO₂与Cond（电导率）和TDS（总溶解固体物含量）呈正相关.而丰枯水期pH与pCO₂都呈显著负相关.丰水期和枯水期pCO₂均为过饱和状态,表现为大气CO₂的源（大气pCO₂值为40.63 Pa）.通过计算得出该研究区CO₂扩散通量（F）丰枯水期分别为49.27—193.82 mmol·m^-2·d^-1、54.02—102.83 mmol·m^-2·d^-1,平均通量为104.998 mmol·m^-2·d^-1和76.822 mmol·m^-2·d^-1.与世界其他水库相比,库区水体丰枯水期CO₂扩散通量低于热带地区,普遍高于亚热带、温带地区.更多还原

【Abstract】 In order to understand the variation of carbon dioxide partial pressure and the diffusion flux of carbon dioxide water in the backwater area of the karst plateau reservoir in wet and dry season, this paper took the Yunnan-Guizhou Plateau Karst Reservoir-Wanfeng Lake as an example. And the surface of the water body in the backwater area of this reservoir was monitored and sampled in September 2016 and February 2017. Then, the water parameters were detected on site by using the water quality parameter instrument. Other remaining water parameters were further measured and analyzed in the laboratory,and pCO₂ was calculated by the principle of water chemical equilibrium and Henry′s law. The results showed:（1） the variation range of the surface pCO₂ in wet season was 124.84—374.06 Pa with the average value of 219.580 Pa.（2） the variation range of the surface pCO₂ in dry season was 210.19—371.53 Pa with the mean value of 290.607 Pa, and the pCO₂ value during the wet season was lower than the dry season. Correlation analysis showed:（1） pCO₂ was negatively correlated with temperature（T） during the dry season, and pCO₂ was positively correlated with conductivity（Cond） and total dissolved solids content（TDS）.（2） There was a strong negative correlation between pH and pCO₂ in the wet and dry season. The pCO₂ in the wet and dry period was supersaturated, which was expressed as the source of atmospheric CO₂（atmospheric pCO₂ value is 40.63 Pa）.The calculation results showed that the CO₂ diffusion flux（F） in the study area was 49.27—193.82 mmol·m^-2·d^-1 with the average flux of 104.998 mmol·m^-2·d^-1.In the dry season, the diffusion flux of CO₂ was 54.02—102.83 mmol·m^-2·d^-1 with average diffusive flux of 76.822 mmol·m^-2·d^-1. Compared with other reservoirs in the world, the CO₂ emission flux in the abundance and dry season of the reservoir area was lower than that in the tropics, which was generally higher than that in the subtropical and temperate regions.更多还原