Quantitative and qualitative assessment of deadwood in natural stands of Hyrcanian forests (Case study: Gorazbon district of Kheyrud, Nowshahr)

The conservation value of Coarse Woody Debris (CWD), as critical microhabitat component, in forest ecosystems led to increasingly expand interests in researches about it. The scientific CWD information had gradually considered by decision-makers for implementing forestry planning. In this study, due to evaluate qualitative and quantitative characters of CWD and its proportion to live standing trees, full callipering method was applied. Data were collected from an unmanaged parcel (parcel no. 37, Gorazbon district, Kheyrud forest) situated in southern slopes of Caspian beech forests. The study site has never been under wood exploitation. The data of CWD (middle diameter ≥ 10 cm) and stand (D.B.H ≥ 7.5 cm) were measured using full calipering method. The results of this study illustrated the average number of live standing trees, snags, and fallen trees were 357, 8, and 26 per ha, respectively. Between all species, hornbeam had the highest volume proportion both in live standing trees and CWD. One fifth of total CWD volume was accounted to sangs and stumps and about half of the total volume was exposure in low degree of decomposition. CWD volume amounted 3.5% of total yield of site study. In summary, total CWD volume is lower than optimal value considered for CWD in temperate forests which sets alarms that any removal of CWD could bring irrecoverable consequences in site study.