Carbon and nitrogen stock in deadwood biomass in natural temperate forest along a soil moisture gradient

Abstract

Deadwood is an important element of properly functioning forest ecosystems and plays a very important role in the maintenance of biodiversity, soil fertility, and carbon sequestration. The main aim of the study was to assess the amount of deadwood, its decay rates, carbon and nitrogen stock in deadwood biomass against the background of differently moistened soils. The investigation was carried out in Czarna Rózga Reserve in central Poland. Forty circular plots of 0.1 ha each were established in a regular grid of points (100 × 300 m). The study included the sequence of soil humidity: fresh, moist and wet. All live and dead trees were measured on each test plot. Additionally, samples of wood from different species were taken from lying logs in five decay classes for carbon and nitrogen concentration determination. The highest stocks of deadwood were related with fresh variant. In the wet variant the increase in stock of deadwood can be explained by the slowdown of decay processes during periods of excessive humidity, causing periodic anaerobic conditions. The soil conditions determine the species composition and structure of the stand, which affects the carbon and nitrogen stock in lying dead trees.