The concept of lakes “evolving” phosphorus (P) limitation has persisted in limnology despite limited direct evidence. Here, we developed a simple model to broadly characterize nitrogen (N) surpluses and deficits, relative to P, in lakes and compared the magnitude of this imbalance to estimates of N gains and losses through biological N transformations. The model suggested that approximately half of oligotrophic lakes in the U.S.A. had a stoichiometric N deficit, but 72–89% of eutrophic and hypereutrophic lakes, respectively, had a similar N deficit. Although reactive N appeared to accumulate in the most oligotrophic lakes, net denitrification perpetuated the N deficit in more productive lakes. Productive lakes exported reactive N via biological N transformations regardless of their N deficit. The lack of N accumulation through N fixation underscores the need for a modern eutrophication management approach focused on reducing total external nutrient loads, including both N and P.
- Award ID(s):
- 1840715
- NSF-PAR ID:
- 10168407
- Date Published:
- Journal Name:
- Hydrobiologia
- ISSN:
- 0018-8158
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1007/s10750-019-04087-y
