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Changes in Aquatic Macrophytes after Liming Thrush Lake, Minnesota
Author(s) -
Hagley Cynthia A.,
Wright David,
Owen Christopher J.,
Eiler Paul,
Banks Marilyn
Publication year - 1996
Publication title -
restoration ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.214
H-Index - 100
eISSN - 1526-100X
pISSN - 1061-2971
DOI - 10.1111/j.1526-100x.1996.tb00182.x
Subject(s) - macrophyte , potamogeton crispus , dominance (genetics) , littoral zone , aquatic plant , biology , ecology , moss , potamogeton , botany , lichen , biochemistry , gene
Thrush Lake, Minnesota, was treated with limestone in 1988 to evaluate the efficacy of protective base addition against the loss of sport fisheries in a sensitive, mildly acidic lake. Prior to treatment, the lake was stressed (pH 6.46, ANC 64 μeq/L) but not severely degraded by acidic deposition and had a macrophyte community typical of lakes in northeastern Minnesota with low acid‐neutralizing capacity (ANC). This paper describes the changes observed in aquatic plant communities during the 5 years after treatment, as pH and ANC slowly returned to pretreatment levels. Sphagnum platyphyllum , intolerant of non‐acid conditions, was completely eliminated from the lake. The charo‐phyte, Nitella , that originally shared dominance in the deep littoral zone with S. platyphyllum , decreased in importance during the first 2 years after treatment. Two vascular plants, Potamogeton pusillus and Najas flexilis , were first found in the lake the year after treatment and were abundant for 2 years after liming, probably in response to a combination of more neutral pH and reduced cover of Nitella. As the ANC and pH slowly returned to pretreatment conditions, Nitella again increased in coverage and depth range, with a concomitant decrease in P. pusillus and N. flexilis. The moss, S. platyphyllum , had not reinvaded the lake by 1993, 2 years after its dramatic decline.