Soil chemical properties, amount of litterfall and nutrients recycling into Caucasian elm, maple and ash plantation stands at Darabkola Experimental Forest Station

In this experiment, soil nutrients, amount of autumn litterfall and nutrients recycling via litterfall into forest floor and their relationships to each other were studied in three stands (Elm, Maple and Ash) at Darabkola Experimental Forest of Sari Agricultural Sciences and Natural Resources University (North of I.R. Iran). Soil samples were made from 0-15 cm depth of soil surface and their chemical properties (pH, EC and the concentrations of N, P, K, Ca and Mg) were tested. Three litter traps (50×50 cm) were randomly placed in each stand and litter was collected at monthly intervals in autumn. Because leaves usually form a significant percentage of litterfall amount, they were collected from each litter-trap at different months of autumn, dried and sieved and finally analyzed. Results showed that there was significant difference (p<0.05) between the tree species in terms of soil nutrient concentration,except P and K contents). The lowest amount of soil N, P, K, Ca and Mg belonged to Ash plantation. Overall, the greatest and the lowest amount of litterfall belonged to Maple and Ash species, respectively. The results showed that the stands were able to change th soil properties to some extent. It might be concluded that these changes are consistent with the differences observed in respect to the recycled nutrients at each stand.