EJSSEurasian Journal of Soil ScienceEurasian J Soil Sci2147 - 4249Federation of Eurasian Soil Science Societieshttp://ejss.fesss.org/10.18393/ejss.2013.1.069-07510.18393/ejss.2013.1.069-075Soil dehydrogenase activity of natural macro aggregates in a toposequence of forest soilMaira Kussainova madgu@inbox.ruMurat Durmuş Aylin Erkoçak 2169 - 752013-01-262013-04-042013-04-092013-04-15 Copyright © 2016 The authors and Federation of Eurasian Soil Science Societies The main objective of this study was to determine changes in soil dehydrogenase activity in natural macro aggregates development along a slope in forest soils. This study was carried out in Kocadag, Samsun, Turkey. Four landscape positions i.e., summit, shoulder backslope and footslope, were selected. For each landseape position, soil macro aggregates were separated into six aggregate size classes using a dry sieving method and then dehydrogenase activity was analyzed. In this research, topography influenced the macroaggregate size and dehydrogenase activity within the aggregates. At all landscape positions, the contents of macro aggregates (especially > 6.3 mm and 2.00–4.75 mm) in all soil samples were higher than other macro aggregate contents. In footslope position, the soils had generally the higher dehydrogenase activity than the other positions at all landscape positions. In all positions, except for shoulder, dehydrogenase activity was greater macro aggregates of Topograpy, soil, aggregate, dehydrogenase activity