The Upper Clark Fork River (UCFR), Montana, a mid-order well-lit system with contemporary anthropogenic nitrogen (N) enrichment and natural geogenic sources of phosphorus (P), experiences annual algal blooms that influence ecosystem structure and function. This study was designed to assess the occurrence of riverine algal blooms (RABs) in the UCFR by characterizing the succession of periphyton and biogeochemical conditions following annual snowmelt runoff through autumnal baseflow conditions, and to provide a framework for assessing RAB progression in montane mid-order rivers more broadly. Using a 21-year database (2000–2020) collected over the growing season at three sites, historical assessment of the persistent and recurrent character of RABs in the UCFR showed that the magnitude of the summer bloom was, in part, moderated by snowmelt disturbance. Abundance and growth forms of benthic algae, along with river physicochemistry (e.g., temperature) and water chemistry (N and P concentration), were measured over the course of snowmelt recession for three years (2018–2020) at the same three sites. Results documented the onset of major blooms of the filamentous green algae
This content will become publicly available on June 1, 2024
- NSF-PAR ID:
- 10433466
- Date Published:
- Journal Name:
- Remote Sensing
- Volume:
- 15
- Issue:
- 12
- ISSN:
- 2072-4292
- Page Range / eLocation ID:
- 3148
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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