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Inferring past environmental changes in three Turkish lakes from sub-fossil Cladocera

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Cladocerans are increasingly used in palaeolimnological studies as their community composition is sensitive to both anthropogenic and natural forces in lakes. We present the results of a palaeolimnological investigation of three Turkish shallow lakes located in cold dry steppe and semi-dry Mediterranean climatic regions. The aim was to elucidate historical changes in environmental conditions by analysing sub-fossil cladocerans in 210Pb-dated sediment cores. Sub-fossil cladoceran remains from the surface sediment of 40 Turkish lakes were analysed to examine the environmental factors that most correlated with variation in the cladoceran assemblage. Redundancy analysis showed that salinity, macrophyte abundance, fish density, depth and total phosphorus were the most correlated with change in cladoceran assemblage composition with eigenvalues for the first and the second axes being λ 1 = 0.312 and λ 2 = 0.061, respectively. Sedimentary cladoceran assemblages from three cores were placed passively within the framework of the surface sediment ordination. The results reveal a prevalent impact of salinity, fish abundance and water level changes from the past to present. Thus, using cladoceran-based inferences, we traced key environmental changes related to variation in climate change, restoration and water level regulation over the last century.
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SHALLOW LAKES
Inferring past environmental changes in three Turkish lakes
from sub-fossil Cladocera
Ays¸e I
˙dil C¸akırog
˘lu .Eti E. Levi .U
¨. Nihan Tavs¸anog
˘lu .Gizem Bezirci .
S¸ eyda Erdog
˘an .Nur Filiz .Thorbjørn Joest Andersen .Thomas A. Davidson .
Erik Jeppesen .Meryem Bekliog
˘lu
Received: 15 April 2015 / Revised: 3 November 2015 / Accepted: 6 November 2015 / Published online: 23 November 2015
ÓSpringer International Publishing Switzerland 2015
Abstract Cladocerans are increasingly used in
palaeolimnological studies as their community com-
position is sensitive to both anthropogenic and natural
forces in lakes. We present the results of a palaeolim-
nological investigation of three Turkish shallow lakes
located in cold dry steppe and semi-dry Mediterranean
climatic regions. The aim was to elucidate historical
changes in environmental conditions by analysing
sub-fossil cladocerans in
210
Pb-dated sediment cores.
Sub-fossil cladoceran remains from the surface sed-
iment of 40 Turkish lakes were analysed to examine
the environmental factors that most correlated with
variation in the cladoceran assemblage. Redundancy
analysis showed that salinity, macrophyte abundance,
fish density, depth and total phosphorus were the most
correlated with change in cladoceran assemblage
composition with eigenvalues for the first and the
second axes being k
1
=0.312 and k
2
=0.061,
respectively. Sedimentary cladoceran assemblages
from three cores were placed passively within the
framework of the surface sediment ordination. The
results reveal a prevalent impact of salinity, fish
abundance and water level changes from the past to
present. Thus, using cladoceran-based inferences, we
traced key environmental changes related to variation
in climate change, restoration and water level regula-
tion over the last century.
Guest editors: M. Bekliog
˘lu, M. Meerhoff, T. A. Davidson,
K. A. Ger, K. E. Havens & B. Moss / Shallow Lakes in a
Fast Changing World
A. I
˙.C¸akırog
˘lu (&)E. E. Levi U
¨. N. Tavs¸ anog
˘lu
G. Bezirci S¸ . Erdog
˘an N. Filiz M. Bekliog
˘lu (&)
Limnology Laboratory, Department of Biology, Middle
East Technical University, U
¨niversiteler Mahallesi,
Dumlupınar Bulvarı, No: 1, 06800 Ankara, Turkey
e-mail: ayseidil@gmail.com
M. Bekliog
˘lu
e-mail: meryem@metu.edu.tr
S¸ . Erdog
˘an
Department of Biology, University of Bozok, Yozgat,
Turkey
T. J. Andersen
Department of Geosciences and Natural Resource
Management, University of Copenhagen, Copenhagen,
Denmark
T. A. Davidson E. Jeppesen
Department of Bioscience and the Arctic Research Centre,
Aarhus University, Silkeborg, Denmark
E. Jeppesen
Sino-Danish Centre for Education and Research, Beijing,
China
E. Jeppesen
Greenland Climate Research Centre (GCRC), Greenland
Institute of Natural Resources, Nuuk, Greenland
M. Bekliog
˘lu
Kemal Kurdas¸ Ecological Research and Training Station
Lake Eymir, Ankara, Turkey
123
Hydrobiologia (2016) 778:295–312
DOI 10.1007/s10750-015-2581-x
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
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Branchiopods are small crustaceans that have flattened leaflike legs. They occur in all freshwater habitats and can be abundant enough to form conspicuous swarms. Branchiopods are useful for studies of community and population ecology, animal behavior, functional morphology, evolution of life history. They occupy a key position in aquatic communities, both as important herbivores eating algae and bacteria, and as major prey items of fish, birds, backswimmers, and other aquatic predators. Their fossil remains open a window into the past climate and ecology of lakes. This chapter focuses on the cladocera, a group of four orders of small-sized branchiopods, and on non-cladoceran orders, which are less diverse and typically somewhat larger than the cladocera. The orders of branchiopods, including eight living and two extinct orders are related to each other only distantly. The Branchiopoda are a heterogeneous group of crustaceans that share a few characteristics, principally similar thoracic legs called phyllopods, which are flat, edged with setae, not distinctly segmented, and usually appear to be un branched.