Effects of livestock exclusion on forest tree regeneration (Case study: Ramsar district 1- Iran)

摘要

In order to study the effect of livestock removal on forest regeneration in Ramsar district 1 - Mazandaran Province, compartment 23 of 96 ha in size was selected. The required data were collected for two separate years (2000 and 2009) and compared together. To assess the regeneration abundance, the analysis was carried out in both years using systematic random sampling with the grid dimensions of 150 x 200 m and sample plot of 100 m2. Within each sample plot, regeneration conditions were categorizedin 4 classes: seedling with height less than 1.30 m, diameter at breast height 0-2.5, 2.5-7.5 and 7.5-12.5 cm. Results showed that the regeneration of tree species belonged to Fagus orientalis, Carpinus betulus, Acer spp., Alnus spp., Tilia begonifolia,Ulmus glabra and Cerasus avium. The comparison of the obtained results in two years (2000 and 2009) showed that the mean regeneration of all tree species increased in 2009 as it was reflected in all 4 diametric classes. There was a statistically significant difference between the means of tree regeneration abundance in 2000 and 2009 (P < 0.01, df = 8, x2 = 748.661). Based on obtained results, the removal of livestock from the forest led to a significant increase in the regeneration establishment in a period of 9 years. The increase was more than 110% in 2009. It is concluded that the removal of livestock from the forest and the forest conservation plans are essential in regeneration establishment within the study area.