Review of indicators and field methods for monitoring biodiversity within national forest inventories. Core variable: Deadwood

Abstract

Deadwood is one of the four elements taken into account in this review of indicators and field methods and is often considered as a key indicator of forest biodiversity. We have analysed the main types of surveys and have realised how greatly the needs and constraints used to monitor deadwood can vary among them. For instance, classical National Forest Inventories usually tend to avoid time-consuming collecting methods. In the wide variety of existing definitions of deadwood, such inventories require simple and clear definitions, especially in terms of quantified thresholds. Thus, deadwood is properly described by characterising several components, such as snags, logs, stumps, branches and fine woody debris. Deadwood sampling methods alter depending on the different components and dimensions considered (standing dead trees, lying dead trees and branches, etc. assessed quantitatively). Attributes such as tree species and stage of decay are used mainly to qualify the deadwood components. The deadwood volume estimations are usually based on classical approaches already applied to living or felled trees: volume equations and/or formulas giving the volumes of common geometric solids. The purpose of this paper is to focus on different deadwood assessment techniques and to provide the information necessary to identify the most relevant methods for collecting deadwood data. The latter is used to build indicators that characterise the evolution of forest biodiversity at the scale of large forest territories.

Deadwood distribution in European forests

“…biomes, ecological regions, forests types, etc.) as well as the management policies in different Countries or areas (Hekkala et al, 2016;Korjus & Laarmann, 2015;Lassauce et al, 2011;Merganičová, Merganič, Svoboda, Bače, & Šebeň, 2012;Rondeux & Sanchez, 2010).…”

Effect of deadwood of different tree species in various stages of decomposition on biochemical soil properties and carbon storage

“…In the case of stumps, the basal diameter (D B ) and height (H) were measured. The length (L) and half-length diameter (D 1/2L ), as the main attributes (Rondeux and Sanchez 2009), were defined for lying dead trees. The diameter measurements were conducted using a circumeter, with an accuracy of 0.1 cm.…”

“…Due to the inability to determine the tree species to which decaying logs and stumps with very advanced decomposition belonged (decay classes 5 and 6 for stumps, decay class V for logs) and the failure to yield soil micronutrients by deadwood in the first two decay classes (Stokland et al 2004, Rondeux andSanchez 2009), only the third and fourth decay classes of dead trees were taken into account in the analysis. Moreover, the results were representative of each study site, as stumps in decay classes 3 and 4 and dead lying trees in decay classes III and IV were the most numerous ( Fig.…”

Deadwood volume in strictly protected, natural, and primeval forests in Poland

“…Surveys and monitoring of deadwood volume in forests provide useful indicators of habitat quality (Rondeux and Sanchez 2010). Previous research has shown that deadwood, whether standing or downed, constitutes an integral part of forest ecosystems, providing obligatory or facultative habitats for many organisms, such as bryophytes, lichens, fungi, and vascular plants (Dittrich et al 2014;Preikša et al 2015), as well as a variety of invertebrate and vertebrate animals (Bütler et al 2004;Stokland et al 2012).…”