In:
Limnology and Oceanography, Wiley, Vol. 51, No. 1part2 ( 2006-01), p. 772-780
Abstract:
We measured the isotope composition of whitefish (Coregonus lavaretus) scales from 50‐yr collections to determine the pattern of change of δ 13 C during the eutrophication and reoligotrophication of two subalpine lakes: Lakes Constance and Geneva. The isotope composition of scales from Lake Annecy, a subalpine lake that has been protected from eutrophication, was also determined, to provide a control value for modifications in the values of whitefish scale δ 13 C in the absence of any significant changes in the trophic status of the lake. In Lakes Constance and Geneva, changes in whitefish scales δ 13 C were closely correlated with those in the mean annual phosphorus concentrations and, to a lesser extent, also reflected the efficiency of winter mixing in Lake Geneva. In contrast, in Lake Annecy, whitefish δ 13 C exhibited only minor changes during the survey. Changes in whitefish scale δ 13 C with the trophic status of Lakes Geneva and Constance were not linked to either a shift in whitefish feeding behavior or to alterations in the length of the pelagic trophic chain. Hence, the pattern of variation of whitefish δ 13 C during the last decades mirrored the lakes' trophic history. The responses of the Lakes Geneva and Constance to changes in P tot were strictly synchronous and parallel, with a response during restoration that may have been the result of the antagonism between the effects of the falling phosphorus concentration and increasing temperature.
Type of Medium:
Online Resource
ISSN:
0024-3590
,
1939-5590
DOI:
10.4319/lo.2006.51.1_part_2.0772
Language:
English
Publisher:
Wiley
Publication Date:
2006
detail.hit.zdb_id:
2033191-5
detail.hit.zdb_id:
412737-7
SSG:
12
SSG:
14
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