<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>Knowledge about the seasonal dynamics of tree growth and its relationship with environmental factors is necessary to eliminate the uncertainty due to ongoing climate change and for more precise growth modelling when re-measurements are done periodically. Despite the increasing number of studies monitoring seasonal wood formation, a considerable part of European forests, including Estonia, lacks such information. In this article, we present a date-dependent model for determining the share of seasonal radial growth for the three most common tree species in the region (Scots pine, Norway spruce and silver birch) for Estonian conditions. Since seasonal tree growth monitoring data were unavailable for Estonia, we used published seasonal radial growth data from Lithuania by <xref ref-type="bibr" rid="j_fsmu-2022-0014_ref_031">Dr Adomas Vitas (2011)</xref>. We tested four functions (Kumaraswamy, Weibull, Gompertz and logistic) on obtained data to approximate the seasonal development of radial growth. Kumaraswamy’s function could track the course of seasonal radial growth gains the best; thus, this function was chosen for further use. We obtained data on intra-annual radial growth from published research studies from neighbouring countries and determined the dates of growth initiation and cessation for Estonian conditions. Finally, we combined Kumaraswamy’s function and the predicted radial growth onset and cessation dates into the model that could predict the seasonal growth course and thus were able to estimate the share of newly formed increment from the dates.</p>
</abstract>

Knowledge about the seasonal dynamics of tree growth and its relationship with environmental factors is necessary to eliminate the uncertainty due to ongoing climate change and for more precise growth modelling when re-measurements are done periodically. Despite the increasing number of studies monitoring seasonal wood formation, a considerable part of European forests, including Estonia, lacks such information. In this article, we present a date-dependent model for determining the share of seasonal radial growth for the three most common tree species in the region (Scots pine, Norway spruce and silver birch) for Estonian conditions. Since seasonal tree growth monitoring data were unavailable for Estonia, we used published seasonal radial growth data from Lithuania by Dr Adomas Vitas (2011). We tested four functions (Kumaraswamy, Weibull, Gompertz and logistic) on obtained data to approximate the seasonal development of radial growth. Kumaraswamy’s function could track the course of seasonal radial growth gains the best; thus, this function was chosen for further use. We obtained data on intra-annual radial growth from published research studies from neighbouring countries and determined the dates of growth initiation and cessation for Estonian conditions. Finally, we combined Kumaraswamy’s function and the predicted radial growth onset and cessation dates into the model that could predict the seasonal growth course and thus were able to estimate the share of newly formed increment from the dates.

A date-dependent model for determining the share of tree seasonal radial growth for Estonian conditions

Forestry Studies

This work is licensed under the Creative Commons Attribution 4.0 International License.

Puude hooajalise radiaalkasvu mõõtmiskuupäevaks moodustunud osa arvutusmudel Eesti tingimuste jaoks

Knowledge about the seasonal dynamics of tree growth and its relationship with environmental factors is necessary to eliminate the uncertainty due to ongoing...

A date-dependent model for determining the share of tree seasonal radial growth for Estonian conditions

Article Category: Research paper

Published Online: May 04, 2023

Page range: 76 - 89

Received: Nov 04, 2022

Accepted: Dec 18, 2022

DOI: https://doi.org/10.2478/fsmu-2022-0014

Keywords
diameter increment, intra-annual growth, age assessment, Kumaraswamy function, permanent sample plot network, Estonia

© 2022 Andres Kiviste et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

A date-dependent model for determining the share of tree seasonal radial growth for Estonian conditions

Article Category: Research paper

Published Online: May 04, 2023

Page range: 76 - 89

Received: Nov 04, 2022

Accepted: Dec 18, 2022

DOI: https://doi.org/10.2478/fsmu-2022-0014

Keywordsdiameter increment, intra-annual growth, age assessment, Kumaraswamy function, permanent sample plot network, Estonia

© 2022 Andres Kiviste et al., published by Sciendo

This work is licensed under the Creative Commons Attribution 4.0 International License.

Keywords
diameter increment, intra-annual growth, age assessment, Kumaraswamy function, permanent sample plot network, Estonia