Estimation of coarse woody debris stocks in forest ecosystems of Slobozhansky national nature park

Abstract

Dead wood is an important component of forest ecosystems. It performs a number of environmental functions. Coarse woody debris includes standing dead trees, fallen dead trees, fragments of fallen trees (trunks), branches (fragments of branches), and rough tree roots. It is a substrate and habitat for living organisms, including a number of species of mosses, lichens, fungi, invertebrates, as well as birds and mammals. Woody detritus plays an important role in the biological cycle of substances and energy, and carbon deposition, is a source of nutrients. Therefore, the study of quantitative and qualitative features of dead wood, in particular on protected areas, is a considerable nowadays problem. The aim of the work is to estimate identified by forest inventory stocks of dead wood in forest ecosystems of Slobozhansky NNP by categories, as well as to analyze the distribution of its volumes in stands of dominant tree species and forest types. The estimation of coarse woody debris stocks was performed based on forest inventory data of Slobozhansky National Nature Park conducted by Ukrainian State Project Forestry Production association “Ukrderzhlisproekt”. Data from 493 forest stands of nine tree species were analyzed. The stock of the following fractions of coarse woody debris was studied: standing dead wood, fallen (downed) dead wood. Data analysis was performed using MS Excel 2016 software. It was found that the total area of forest stands in which standing or downed dead wood was found during forest inventory was 2149.8 ha, or 47.5% of the total forest area of NNP. The total stock of coarse woody debris was 19478 m3, more than 95% of which is concentrated in the stands of Scots pine (Pinus sylvestris L.) (78.8%) and pedunculate oak (Quercus robur L.) (16.6%). Standing dead wood prevailed (62.1%) fallen dead wood (37.9%) in the structure of dead wood volume. The volume of dead wood was in the range of 5–50 m3∙ha–1, and on average in studied forest ecosystems in which it was found was 9.1 m3∙ha–1. In Scots pine forest stands coarse woody debris was found on an area of 1703.5 hectares with total stock of 15355 m3, consists of standing dead trees (9952 m3, 64.8%) and fallen dead wood (5403 m3, 35.2%). The volume of dead wood in forest stands was 5–50 m3∙ha–1, on average – 9.0 m3∙ha–1. In pedunculate oak stands coarse wood debris was found on an area of 384.7 hectares with a total stock of 3224 m3, consists of standing dead wood (1469 m3, 45.6%) and fallen dead wood (1755 m3, 54.4%). The volume of dead wood in forest stands was 5–20 m3∙ha–1, on average – 8.4 m3∙ha–1.