Brownification on hold: What traditional analyses miss in extended surface water records

WATER RESEARCH

卷:203

Article

Eklof, Karin¹  von Bromssen, Claudia²  Amvrosiadi, Nino^1,3  Folster, Jens¹  Wallin, Marcus B.¹  Bishop, Kevin¹ 

[1] Swedish Univ Agr Sci, Dept Aquat Sci & Assessment, SE-75007 Uppsala, Sweden

[2] Swedish Univ Agr Sci, Dept Energy & Technol Appl Stat & Math, SE-75007 Uppsala, Sweden

[3] Res Inst Sweden, Dept Bioecon & Hlth, SE-75651 Uppsala, Sweden

关键词: Brownification;    Organic matter;    Absorbance;    Watercourses;    Long-term trends;    Generalized additive mixed model;   

DOI  :  10.1016/j.watres.2021.117544

来源: Elsevier

【 摘 要 】

Widespread increases in organic matter (OM) content of surface waters, as measured by color and organic carbon (OC), are a major issue for aquatic ecosystems. Long-term monitoring programs revealed the issue of browni-fication, with climate change, land cover changes and recovery from acidification all suspected to be major drivers or contributing factors. While many studies have focused on the impact and drivers, fewer have followed up on whether brownification is continuing. As time-series of OM data lengthen, conventional data-analysis approaches miss important information on when changes occur. To better identify temporal OM patterns during three decades (1990-2020) of systematic monitoring, we used generalized additive models to analyze 164 time-series from watercourses located across Sweden. Increases in OC that were widespread during 1990-2010 ceased a decade ago, and most color increases ceased 20 years ago. These findings highlight the need to reassess the understanding of brownification's spatial and temporal extent, as well as the tools used to analyze lengthening time series.

【 授权许可】

Free