ISSN:
1573-0417
Keywords:
Lake Arendsee (Germany)
;
paleolimnology
;
nutrients
;
eutrophication
;
diatoms
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Geosciences
Notes:
Abstract To study the algal microfossil assemblages of eutrophic Lake Arendsee (Germany) prior to the beginning of a restoration project, a 47-cm long freeze core, dating back to ca 1800, was taken from the deepest area of the lake. Based on the CRS modeled 210Pb and 137Cs profiles from the core, 1948 is around 15 cm and the sedimentation rate has increased from ∼ 21.2 mg cm-2 yr-1 in 1900 to ∼ 56.6 mg cm-2 yr-1 in 1986. The sediments were dominated by three centric diatoms. Stephanodiscus binatus, a species associated with eutrophic environments, dominated the upper 19 cm of the core. Cyclotella rossii, a species commonly found in less productive freshwater systems, was found to dominate the lower portion of the core and was absent above 16 cm. S. agassizensis was found throughout the core. In addition to the centric diatoms, three penate diatoms were found to be abundant. Fragilaria crotonensis was found throughout the core, but was most abundant from 19 cm to 16 cm. Asterionella formosa was prevalent below 15 cm, while Diatoma elongatum was found to be common from 17 cm to the surface. The abundances of algal remains of cyanobacteria, chlorophytes, cryptophytes and dinoflagellates decrease dramatically below 25 cm. Zooplankton remains were most abundant around 20 cm, with copepod spermatophores, fecal pellets and protozoa remains most common in the lower portion of the core. The major species shifts observed in the core from Lake Arendsee occur in a transition zone between 20 cm and 15 cm (1920–1940), a time when agricultural production was being increase with the use of inorganic fertilizer.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1007906611087
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