the Expedition ARKTIS-XIX/4 of the research vessel POLARSTERN ...

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In the shallow ponds the hydrological measurements were carried out at one surface
sample from the central part. The locations for the hydrological measurements in the
deeper lakes were determined with a hand echo sounder along several profiles
across the lakes, which revealed the maximum water depths of the lake basins. At
locations, where the maximum water depth was measured, samples were taken from
different depths using a water sampler (UWITEC Corp., Austria). The water sampler
is released by a short uplift in a certain depth and contains 5 l of water. Once at the
surface about 1 l was immediately used to measure temperature, O2-saturation and
content, conductivity, and pH value. On selected horizons water samples were taken
in order to determine the anion and cation contents and the contents of methane and
dissolved organic carbon (DOC) throughout the water column. For the analyses of
the DOC, anion, and cation contents three samples of 30 ml were filled into Nalgene
bottles, the latter ones after filtering the water through a 0.45 µm filter. The samples
for cation analyses were additionally fixed by adding 200 ml of NaOH. For the
measurements of the methane content, water was filled into glass bottles, which
contained NaCl in order to release the gas from the water. Finally, the visibility of the
lakes was determined using a Secchi disc.
In general, the lakes on Store Koldewey and Geographical Society Ø belong to high
arctic lakes, and are characterized by relatively low temperatures, high oxygen
content and saturation, low conductivity and low nutrient contents, reflected in a
relatively high visibility (Tab. 6.1-1). During the field period from mid August to mid
September 2003 the lakes were not covered by ice, although a lateral formation of a
thin ice cover was observed at some lakes during cloudless and calm nights.
lake latitude longitude alt.
1
mwd temp. O2-sat. O2-cont. conduct. pH vis. 2
(m asl) (m) (°C) (%) (mg/l) (µS/cm) (m)
Store Koldewey
Melles Lake N76°07’40’’ W018°37’57’’ 166 72.0 4.0- 102- 11.8- 37.0- 7.9-8.1 5.4
6.8 112 14.0 38.0
Duck Lake N76°25’15’’ W018°45’00’’ 118 6.4 6.7- 126- 14.9- 11.0- 8.6-9.0 5.8
7.2 130 15.5 11.9
Hjort Lake N76°25’59’’ W018°45’41’’ 122 6.1 5.3- 115- 14.9- 15.7- 9.1-9.3
5.4 128 15.4 16.3
Goose Lake N76°26’36’’ W018°48’14’’ 115 7.4 4.4- 118- 14.5- 11.0- 8.9-9.1 4.8
4.9 122 15.3 12.2
Lemming
Lake
N76°25’42’’ W018°47’44’’ 121 2.0 5.8 125 15.3 23.7 8.3
Fox Lake N76°15’06’’ W018°41’32’’ 302 57.7 4.7- 111- 13.6- 8.7-9.3 7.5-8.4 8.1
4.8 116 14.5
Raven Pond N76°16’34’’ W018°36’18’’ 104 0.4 2.4 126 16 21.0 8.2
Polar Bear N76°14’10’’ W018°43’48’’ 175 15.9 3.3 121- 15.2- 30.8- 8.2-8.5 7.3
Lake 1
125 15.7 35.1
Polar Bear N76°14’01’’ W018°46’12’’ 129 12.3 3.4- 123- 15.5- 41.3– 8.3-8.4 3.3
Lake 3
3.5 126 16.0 41.5
Musk Ox
Pond
N76°13’57’’ W018°35’55’’ 115 0.2 2.6 120 15.9 26.9 8.4
Panorama N76°14’51’’ W018°45’34’’ 602 c. 0.8 120 15.9 8.0 8.5
Lake
5.0
Geographical Society Ø
Loon Lake N72°53’16’’ W022°08’22’’ 8 11.7 7.4- 120- 14.2- 23.2- 7.6-8.0 3.0
7.8 122 14.6 23.4
1 mwd = maximum water depth 2 visibility measured by Secchi disc
Tab. 6.1-1: Hydrology of lakes and ponds on Store Koldewey and Geographical Society Ø