Common tree definitions for national forest inventories in Europe

Abstract

At the international level, various definitions have been established for the compilation and publication of forest resources assessment results over the last decade. These international definitions frequently rely on terms that are not precisely specified for inventory purposes and do not completely cover the requirements arising from the application of National Forest Inventory (NFI) data. Also, with respect to conventional topics such as forest area and growing stock estimation, several terms and expressions referring to individual trees are not, or are only vaguely, defined until now. Since the individual tree is the basic element of any forest resources assessment, the clarification of tree-related terms is an important part of COST Action E43 to harmonise common reporting of National Forest Inventories. Based on a review of existing definitions and on the requirements for harmonised reporting, common tree-related definitions are established. One objective of this study is to refine and enhance the applicability of available tree and shrub definitions, in particular with regard to the distinction between trees and shrubs. The study also focuses on the parts or "elements" of trees and on the distinction between these elements as they are of particular importance in growing stock and biomass definitions. Furthermore, several definitions for tree characteristics such as "living" and "standing", as well as tree variables such as height, length, diameter at breast height, and crown projection area are adjusted with respect to NFI purposes. A concluding discussion reflects upon the reviewed, refined and newly established definitions. The definitions presented in this paper provide a firm basis for a common set of harmonised reference definitions developed by COST Action E43 and contribute to the precise and consistent use of terms.

The role of European National Forest Inventories for international forestry reporting

“…Thus, a reference definition of each tree element used for defining GS and biomass is also necessary. To establish a clear specification for each element, a multi-step analytical partitioning approach was proposed leading to the unambiguous definition of each tree element (Gschwantner et al 2009). These tree elements are single disjoint parts of the tree that are clearly defined.…”

Stem quality assessment in European National Forest Inventories: an opportunity for harmonised reporting?

“…The definitions were drafted during the meetings of Working Group 1 of Cost Action FP1001 (COST 2015). They rely on the definitions of tree parts such as bole and stem available from Gschwantner et al (2009) and Tomppo et al (2010).…”

“…Furthermore, before any harmonisation of stem quality assessment is made there is a need to harmonise single tree-and timber qualityrelated parameters. This has been the subject of last two COST Actions, E43 (COST 2010) (Vidal et al 2008;Gschwantner et al 2009;McRoberts et al 2009McRoberts et al , 2010Ståhl et al 2012;Tomppo and Schadauer 2012;Tomter et al 2012) and FP1001 (COST 2015. Therefore, this study is primarily focused on stem quality-related parameters assessment in European NFIs.…”

Comparison of field and airborne laser scanning based crown cover estimates across land cover types in Kenya

“…CC is defined as the proportion of ground covered by the vertical projection of tree crowns in percentage (Jennings et al, 1999;Korhonen et al, 2006;Gschwantner et al, 2009). Crown is defined by its outer perimeter and hence the small within crown gaps are considered to belong to the crown.…”