O. Hadas et R. Pinkas, ARYLSULFATASE AND ALKALINE-PHOSPHATASE (APASE) ACTIVITY IN SEDIMENTS OF LAKE-KINNERET, ISRAEL, Water, air and soil pollution, 99(1-4), 1997, pp. 671-679
Arylsulfatase and APase activities were monitored in the upper sedimen
t layer, of Lake Kinneret Israel, a warm, freshwater, monomictic lake
characterized by a heavy spring bloom of the dinoflagellate Peridinium
gatunense. Activity of both enzymes varied with depth and season. Hig
hest activity was measured in July and high activities were monitored
during the stratified period. Low values were observed in winter, when
oxic conditions prevail in the water column and no organic sedimentat
ion occurred. The values for APase ranged from 14-438 nmol PNP g(-1)h(
-1) and for arylsulfatase from 103 to 843 nmol PNP g(-1)h(-1). Highest
APase activity was recorded at 29 degrees C, and most of it took plac
e on mud particles and not in the interstitial waters. There were diff
erences in enzyme activity at different stations in the lake, correspo
nding to differences in nutrient pore water concentrations. Enzymatic
activity in Lake Kinneret sediments was related to lake trophic status
, water levels, and climate conditions, all of which have an impact on
the amount of organic matter reaching the sediments.