Drivers of spatio-temporal patterns of salinity in Spanish rivers: a nationwide assessment

The salinization of freshwaters is a global water quality problem that leads to the biological degradation of aquatic ecosystems. However, little is known about the spatial extent of freshwater salinization and the relative contribution of each human activity (e.g. agriculture, urbanization, mining or shale-gas extraction). Here, we investigated environmental factors that explain spatio-temporal patterns of water salinity and examined the causes, the extent and the degree of salinization of Spanish rivers. Results showed a strong variation in water salinity among river typologies and between river reaches in good and poor ecological status according to the Water Framework Directive. The variation in water salinity was largely explained by a combination of natural (i.e. climate and geology) and anthropogenic (i.e. land use) factors. By contrast, land use factors as urbanization and agriculture were the main drivers of salinization, which affected more than one quarter of the rivers and s...

淡水盐化是一项全球性的水质问题，会引发水生生态系统的生物退化。然而，目前学界对淡水盐化的空间分布范围，以及各项人类活动（如农业、城市化、采矿或页岩气开采）的相对贡献尚缺乏充分认知。本研究针对阐释水体盐度时空分布格局的环境因素展开调研，并对西班牙河流盐化的成因、波及范围与严重程度进行了剖析。研究结果显示，不同河流类型之间，以及符合《水框架指令》（Water Framework Directive）生态等级为良好与较差的河段之间，水体盐度均存在显著差异。水体盐度的变异主要由自然因素（即气候与地质条件）和人为因素（即土地利用类型）共同解释。与之相反，城市化与农业等土地利用因素是盐化的主要驱动因子，其影响范围覆盖了超过四分之一的河流，且...