Seasonal variation of acid phosphatase and dehydrogenase activity in natural and artificial habitats of hazel

The hazels (Corylus avellana) are seen in north region of Iran and many stands grow in upper area of northern slop of Alborz Mountains. Soil is an effective living factor in ecosystem balance. There are many biological and biochemical process in soil which rapidly reacts to environmental stresses. Enzymes have essential roles in these processes. The aim of this research was to study the activities of acid phosphatase and dehydrogenase in two natural hazel habitats (Makesh and Fandoghlo) and compare to their activities in an artificial habitat (Alborz). Soil sampling was done in spring and summer. The activity of acid phosphatase and dehydrogenase was evaluated by enzyme- substrate reaction. Enzymes had more activity in summer in all studied habitats. The more activity of acid phosphatase can be related to growth of hazel roots and secretion of enzyme during growth season. Enzymes showed more activity in Fandoghlo habitat in compared to Makesh ones. The amount of nitrogen, phosphorus and organic matter was less in Fandoghlo habitat which causes more activity of microorganisms to supply plants needs and compensation of low nutrients in soil.