Growth variations in poplar (Populus nigra L.) plantations in riverbanks of Kermanshah Province

In order to evaluate the amount of poplar wood production in traditional poplar farming, an assessment of annual growth in different stands is necessary. In this study 8 Populus nigra stands along margins of different rivers of Kermanshah province were selected for the analysis. A number of 102 variable sample plots were measured by in a systematic random design. In each sample plot growth attributes were measured. The data was analyzed by one-way analysis of variance and Duncan test. In addition, soil samples were measured and the soil data were analyzed by correlation and PCA analysis. Results showed that the annual growth of 6th stand was three times higher than that of 4th stand, with their cumulated annual ranging between 10.3-38 m3. Furthermore, differences were observed in volume, height and diameter growth amongst the stands. Furthermore, differences were observed in volume, height and diameter growth amongst the stands. The conducted PCA analysis of soil samples showed a marginal significant difference amongst the samples, though no significant correlation between volume growth and soil characteristics was observed. For example decreasing EC and pH improved the volume growth, whereas increasing Clay, N and OC budget led to an increase in volume growth. Compared to the previously achieved results in the literature, the amount of poplar growth seems to be rather a function of management operations in farm rather than the genetic and edaphic attributes.