Parameters characterizing the nutrient chemistry of the eleven primary lakes (Allequash, Big Muskellunge, Crystal, Sparkling, and Trout lakes, unnamed lakes 27-02 [Crystal Bog] and 12-15 [Trout Bog], Mendota, Monona, Wingra, and Fish) are measured at multiple depths throughout the year. These parameters include total nitrogen, total dissolved nitrogen, nitrite+nitrate-N, ammonium-N, total phosphorus, total dissolved phosphorus, dissolved reactive phosphorus (only in the southern lakes and not in Wingra and Fish after 2003), bicarbonate-reactive filtered and unfiltered silica (both discontinued in 2003), dissolved reactive silica, pH, air equilibrated pH (discontinued in 2014 in the northern lakes and in 2020 in the southern lakes), total alkalinity, total inorganic carbon, dissolved inorganic carbon, total organic carbon, dissolved organic carbon, and total particulate matter (only in the northern lakes in this data set; total particulate matter in southern lakes starting in 2000 is available in a separate dataset). Sampling Frequency: Northern lakes- monthly during ice-free season - every 5 weeks during ice-covered season. Southern lakes- Southern lakes samples are collected every 2-4 weeks during the summer stratified period, at least monthly during the fall, and typically only once during the winter, depending on ice conditions. Number of sites: 11
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Salmon‐derived nutrient and organic matter fluxes from a coastal catchment in southeast Alaska
Salmon are important vectors for biogeochemical transport across ecosystem boundaries. Here we quantified salmon contributions to annual catchment fluxes of nutrients (N and P) and organic matter (C, N, and P) from a forested catchment in coastal southeast Alaska. Concentrations of ammonium and soluble reactive phosphorus increased by several orders of magnitude during spawning and were significantly correlated with spawning salmon densities. Nitrate concentrations increased modestly during spawning and were not significantly correlated with salmon densities. Salmon had a modest legacy effect on inorganic N and P as evidenced by elevated streamwater concentrations past the end of the spawning period. Dissolved organic carbon concentrations did not respond to the presence of salmon; however, concentrations of dissolved organic nitrogen and phosphorus showed a significant positive relationship to salmon densities. Changes in spectroscopic properties of the bulk streamwater dissolved organic matter pool indicated that streamwater dissolved organic matter became less aromatic and biolabile during spawning. On an annual basis, salmon were the dominant source of streamwater fluxes of inorganic nutrients, accounting for 92%, 65%, and 74% of annual streamwater fluxes of ammonium, nitrate, and soluble reactive phosphorus, respectively. In contrast, fluxes of organic matter were dominated by catchment sources with salmon accounting for <1% of the annual catchment flux of dissolved organic carbon and 12% and 15% of the annual fluxes of dissolved organic nitrogen and phosphorous respectively. These findings indicate that, in small coastal catchments, salmon can be a quantitatively important source of dissolved streamwater nutrients with implications for productivity in downstream estuarine ecosystems.
- Award ID(s):
- 1757348
- NSF-PAR ID:
- 10461141
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Freshwater Biology
- Volume:
- 64
- Issue:
- 6
- ISSN:
- 0046-5070
- Page Range / eLocation ID:
- p. 1157-1168
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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