Stock and structure of deadwood and its importance in carbon accumulation on wet broadleaved forest and riparian alder forest sites

The main aim of study was to present the stock and structure of deadwood in different site conditions. In total. sixteen study plots were established on wet broadleaved forest (Lw) and riparianalder forest (OlJ) sites. The objective was to determine the carbon accumulation in lying dead trees. The investigation was performed in the Czarna Rózga reserve in Central Poland (50°5937N; 20°015E). All live and dead trees were measured on each plot. The species of both live and dead trees were identified as well, and the decay class of the dead trees was assessed. Additionally, samples of different species wood from lying logs in five decay classes were taken for carbon content determination. The study was carried out in the spring of 2017. The average stock of deadwood in the Czarna Rózga reserve on the wet broadleaved forest site amounted to 47 m3/ha, while on the riparian alder forest site it equaled 52 m3/ha. The high stock of deadwood can be explained by the slowdown of decay processes by humidity and anaerobic conditions. Ash was the dominant species in the deadwood pool. Regardless of the site conditions (Lw or OlJ), the stock of ash deadwood was several times higher than the stock of live trees this species. The greater carbon stock in lying dead trees was recorded in riparian alder forest