In this study, dehydrogenase activity assays were used to monitor microbial activity in Israel's Judean Desert, a rain shadow desert along a topoclimatic transect. Four locations at this gradient were studied: the pair Givat Yaarim, Maale Adumim and the pair Mishor Adumim, Kalia. These locations range from semidesert in the west 650 ni above sea level with a 620 mm average annual rainfall to the most eastern station (Kalia) 60 m below sea level with less than 100 mm average annual rainfall. Monthly soil samples were collected between January 1994 and July 1996. The soils, which differ mainly in slope location, were analyzed for dehydrogenase activity in the laboratory using the triphenylformazan extraction method. Although both enzyme activity and soil moisture content were found to be significantly different at each location, no significant correlation between them was obtained. However, drying of the soil during the long summer period resulted in a reduction in dehydrogenase activity, while increased soil moisture resulted in a marked increase in dehydrogenase activity.
Bibliographical noteFunding Information:
Received 23 September 1997; 4 February 1998. This research was supported by a grant from the Ministry of Science and the KFA-BEO, For-schungszentrum Jülich GmbH/Projektträger für Biologie, EnergieundÖkologie. Address correspondence to Prof. Y. Steinberger, Department of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel.E-mail:firstname.lastname@example.org