Effects of small freshwater inflow volumes on water and sediment quality based on USGS gaged flows from 2015-09-30 to 2016-09-15

Discharge was sampled daily at two stations in the Guadalupe and Tres Palacios Rivers to estimate freshwater inflow to estuaries. The Guadalupe Estuary’s average monthly freshwater inflow rate was 92% higher than the Lavaca-Colorado Estuary, so a larger flow volume increase is necessary to affect estuarine health in the Guadalupe Estuary. This analysis indicated that an increased small volume, as low as 10% of freshwater inflow volume, can have positive benefits to estuarine conditions and health. Thus, hydrological protection or restoration projects based on small volumes can improve estuaries degraded by freshwater diversions. An accompanying study conducted simultaneously contains nutrient, chlorophyll, and benthic community data (HI.x962.000:0018, https://doi.org/10.7266/6ptst906).

研究人员每日对瓜达卢佩河（Guadalupe River）与特雷斯帕拉西奥斯河（Tres Palacios River）的两处监测站点的河流流量（Discharge）开展采样工作，以估算汇入河口的淡水输入量。瓜达卢佩河口（Guadalupe Estuary）的月均淡水输入速率较拉瓦卡-科罗拉多河口（Lavaca-Colorado Estuary）高出92%，因此若要对瓜达卢佩河口的生态健康产生影响，需实现更大幅度的径流量提升。本分析表明，小幅提升淡水输入量（低至总输入量的10%）即可对河口环境与健康产生积极效益。据此，基于小幅流量调控的水文保护与修复工程，可改善因淡水引水（freshwater diversions）而退化的河口生态系统。本研究同步开展的配套研究包含营养盐、叶绿素及底栖生物群落（benthic community）相关数据（数据集编号：HI.x962.000:0018，https://doi.org/10.7266/6ptst906）。