Inventory of dead wood in managed and old-growth forests on permanent sample plots

Abstract

Introduction

For the forests of Europe, a declared number of environmental criteria and indicators of the state, trends, and political challenges for the conservation of biological diversity in forest ecosystems have been determined. Within the framework of Criterion 4: Maintenance, Conservation, and Appropriate Enhancement of Biological Diversity in Forest Ecosystems, a number of quantitative indicators were identified, one of which is “dead wood”, namely the presence and amount of recorded standing or lying dead wood in forests and other forest lands. Deadwood management is a relatively new concept for Ukraine, which has been actively discussed and promoted since 2000 but which is still undeclared and not entirely understood in practice. For decades, forestry management in many European countries and Ukraine considered dead wood to be the “enemy of the forest”, and efforts were invested in the systematic removal of it from forests through forestry, observing forest rules and regulations (for example, sanitary rules, logging rules, etc.). The importance of dead wood to forest ecosystems is widely recognized as it is used as an indicator of sustainable forest management and its presence is one of the most important indicators of its naturalness. The amount of dead wood in forests undisturbed by economic activity differs significantly from those forests where forestry activities are carried out. As an example, mainly at the late succession stages of natural forests, a significant amount of dead wood was revealed in terms of volume, composition, and stages of decomposition.

The aim of the work was a detailed inventory of standing and lying dead wood by comparative studies in commercial and old-growth forests.

Materials and Methods

The inventory of standing and lying dead wood was carried out through comparative studies in managed and old-growth forests. For the study, 40 circular sample plots of 500 m² each were selected: 20 plots in areas where forestry activities are carried out (340 hectares) and 20 in places with no forestry activities (200 hectares). The experimental sites were located within the range of 660-1,240 m above sea level. The amount of dead wood was determined by two components: lying on the ground dead wood (LDW) and standing dead wood (SDW). It should be noted that the volume of dead wood per hectare is an indirect estimate. For standing dead wood, the height was measured, and the decomposition class and the presence of knots on the trunk were established. The inventory of the lying dead wood was carried out by the transect method, in which all dead wood with a diameter of more than 7 cm was taken into account.

Results

Inventory of standing (SDW) and lying (LDW) deadwood in managed and old-growth forests of the Ukrainian Carpathians made it possible to determine their stock and percentage of the total biomass. The average stock of SDW in managed forests is 7.7 m³·ha^-1 and in old-growth forests 38.3 m³·ha^-1. The percentage of the total biomass is 0.97% and 3.82%, respectively. The average LDW stock in managed forests is 44.7 m³·ha^-1, and in old-growth forests, it is 73.9 m³·ha^-1. The percentage of the total biomass is 5.7% and 7.4%, respectively. The number of standing and fallen dead trees in old-growth forests is almost two times less, and the stock is twice as high as in managed forests. Within the framework of the research sites, the stages of decomposition of dead wood by tree species were determined and their comparative analysis was carried out.

Conclusions

The established indicators of the availability and stock of deadwood contributed to the development of recommendations “The role of deadwood and innovative measures for its management” aimed at increasing the productivity of forest ecosystems, their resilience to climate change, and biodiversity conservation.