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Abstract Understanding relationships between stream chemistry and watershed factors: land use/land cover, climate, and lithology are crucial to improving our knowledge of critical zone processes that influence water quality. We compiled major ion data from >100 monitoring stations collected over 60 years (1958–2018) across the Colorado River Watershed in Texas (103,000 km2). We paired this river chemistry data with complementary lithology, land use, climate, and stream discharge information. Machine learning techniques were used to produce new insights on controls of stream water chemical behavior, which were validated using traditional multivariate analyses. Studies on stream flow and chemistry in the American west and globally have shown strong relationships between major ion chemical composition, climate, and lithology which hold true for the Colorado River basin in this study. Reactive minerals, including carbonates and evaporites, dominate major ion chemistry across the upper, low‐precipitation regions of the watershed. Upstream and middle reaches of the Colorado River showed shifts from Na‐Cl‐SO4dominated water from multiple sources including dissolution of gypsum and halite in shallow groundwater, and agricultural activities, to Ca‐HCO3water types controlled by carbonate dissolution. In the lower portion of the watershed multiple analyses demonstrate that stream chemistry is more influenced by greater precipitation and the presence of silicate minerals than the middle and upstream reaches. This study demonstrates the power of applying machine learning approaches to publicly available long term water chemistry data sets to improve the understanding of watershed interactions with surficial lithology, salinity sources, and anthropogenic influences of water quality.
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Human–river relationships depend on human–human relationships: River and watershed organizations in three western US states
Abstract Human–nature relationship concepts are held collectively within society and guide environmentally oriented actions. This article explores the roles played by environmental organizations, particularly those focused on rivers and watersheds, in catalyzing interaction and action driven by human–river relationship goals. Interviews were conducted with representatives from 64 river and watershed organizations in Montana, Utah, and Wyoming in 2022. Organizational representatives were asked about mission focus areas, human–river relationships, the knowledge they draw upon to guide their efforts, and factors and obstacles that enable and constrain their progress and success. These qualitative data reveal a strong orientation toward steward and partner types of human–nature relationship concepts; however, there are discrepancies in conceptual interpretations. For river and watershed organizations in the US Intermountain West, human–river relationship goals depend strongly on human–human relationships in the form of diverse knowledge integration, collaboration, partnerships, trust, and communication in order to achieve their river‐related goals.
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- Award ID(s):
- 2115169
- PAR ID:
- 10418997
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- River Research and Applications
- Volume:
- 40
- Issue:
- 9
- ISSN:
- 1535-1459
- Format(s):
- Medium: X Size: p. 1687-1697
- Size(s):
- p. 1687-1697
- Sponsoring Org:
- National Science Foundation
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