Development phase delineation in primeval European beech using the dominant biomass strata protocol

Abstract Reliable characterizations of developmental condition can help elucidate disturbance regimes, characterize structural development, and identify and describe old-growth. However, current forest life cycle development phase classifications are based on inconsistent, incompatible, or unreliable a priori archetypal structures that fail to capture the natural dynamics of old-growth European beech (Fagus sylvatica L.) forests subject to a small-scale disturbance regime. We demonstrate an alternative protocol for capturing phases of biomass upgrade based solely on the proportion of live-tree volume in seven progressive tree size classes, with an optional deadwood-share cut-off (30%) to also identify deadwood-rich patches when desired. The proportions of a 10-ha primeval European beech forest in the Ukraine assigned in 156.25 m2 grid cells to each of the Dominant Biomass Strata phases were in keeping with previously reported estimates. Amid a matrix (>60%) of Overstory, Upper Overstory, and Emergent phases, roughly a tenth of the area was classified to the early Open/Seedling and Understory phases, the Lower and Upper Midstory phases, and the Lower Overstory phase, respectively. Further, 12% of grid cells—across all phases—were deadwood-rich. The biomass proxies of live volume, basal area, and mean tree size increased distinctly with each subsequent phase, and were lower in the deadwood-rich category, in accordance with the forest life cycle. Structural complexity proxies varied inversely with biomass when defined as the distribution of volume among canopy layers, but similarly to biomass when defined using metrics based on tree size differences. High volumes of large-diameter deadwood were observed in all phases, consistent with previous observations of acyclic transitions following mortality. In pure primeval European beech, the synchronous pattern of biomass and size-based structural complexity metrics (including the standard deviation of tree diameters, the Gini coefficient for basal area, the diameter differentiation index T, and the structural complexity index SCI) may provide a natural model for the simultaneous optimization of volume and small-scale complexity in managed forests. With local adaptation, the proposed Dominant Biomass Strata classification protocol could be applicable to any site or forest type and used to classify stand development phases in young forests following stand-initiation or to classify patch development phases in old-growth forests subject to maintenance dynamics.

[1]  F. Biondi,et al.  Lessons from the wild: slow but increasing long-term growth allows for maximum longevity in European beech. , 2019, Ecology.

[2]  E. Zenner,et al.  Multi-aged micro-neighborhood patches challenge the forest cycle model in primeval European beech , 2020 .

[3]  B. Mihók,et al.  Thirty years of gap dynamics in a central european beech forest reserve , 2008 .

[4]  M. Saniga,et al.  Structural Diversity in a Mixed Spruce-Fir-Beech Old-Growth Forest Remnant of the Western Carpathians , 2018, Forests.

[5]  E. Zenner.  Deriving restoration targets from diameter distributions of Dominant Biomass Strata development phases in an old-growth European beech forest , 2021 .

[6]  T. Vrška,et al.  How cyclical and predictable are Central European temperate forest dynamics in terms of development phases? , 2018 .

[7]  S. McMahon,et al.  Patch mosaic of developmental stages in central European natural forests along vegetation gradient , 2014 .

[8]  J. Wiens.  Spatial Scaling in Ecology , 1989 .

[9]  A. Zingg,et al.  Structure of virgin and managed beech forests in Uholka (Ukraine) and Sihlwald (Switzerland): a comparative study , 2005 .

[10]  David E. Hibbs,et al.  A new method for modeling the heterogeneity of forest structure. , 2000 .

[11]  Dynamics in Central European near-natural Abies-Fagus forests: Does the mosaic-cycle approach provide anan appropriate model? , 2008 .

[12]  H. Mayer,et al.  Struktureller und entwicklungsdynamischer Vergleich der Fichten-Tannen-Buchen-Urwälder Rothwald/Niederösterreich und Čorkova Uvala/Kroatien , 2007, Forstwissenschaftliches Centralblatt.

[13]  R. D. Nyland,et al.  Beech regeneration research: From ecological to silvicultural aspects , 2010 .

[14]  A. Alessandrini,et al.  Old-growth attributes in a network of Apennines (Italy) beech forests: Disentangling the role of past human interferences and biogeoclimate , 2012 .

[15]  Martina L. Hobi,et al.  Gap pattern of the largest primeval beech forest of Europe revealed by remote sensing , 2015 .

[16]  C. Leuschner,et al.  Classifying development stages of primeval European beech forests: is clustering a useful tool? , 2018, BMC Ecology.

[17]  E. Zenner,et al.  Patchiness in old-growth oriental beech forests across development stages at multiple neighborhood scales , 2019, European Journal of Forest Research.

[18]  Bruce C. Larson,et al.  Forest Stand Dynamics , 1990 .

[19]  A. Bobiec,et al.  Rich deciduous forests in Białowieża as a dynamic mosaic of developmental phases: premises for nature conservation and restoration management , 2000 .

[20]  J. Diaci,et al.  Gap disturbance patterns of a Fagus sylvatica virgin forest remnant in the mountain vegetation belt of Slovenia , 2005 .

[21]  M. Saniga,et al.  Stand structure and temporal variability in old-growth beech-dominated forests of the northwestern Carpathians: A 40-years perspective , 2012 .

[22]  T. Nagel,et al.  Gap disturbance regime in an old-growth Fagus-Abies forest in the Dinaric Mountains, Bosnia-Herzegovina , 2008 .

[23]  E. Zenner,et al.  Integration of small-scale canopy dynamics smoothes live-tree structural complexity across development stages in old-growth Oriental beech (Fagus orientalis Lipsky) forests at the multi-gap scale , 2015 .

[24]  S. Korpel,et al.  Die Urwälder der Westkarpaten , 1995 .

[25]  E. Zenner,et al.  Development phase convergence across scale in a primeval European beech (Fagus sylvatica L.) forest , 2020 .

[26]  H. Bugmann,et al.  Pattern and process in the largest primeval beech forest of Europe (Ukrainian Carpathians) , 2015 .

[27]  C. Ginzler,et al.  Stand inventory data from the 10 ha forest research plot in Uholka: 15 years of primeval beech forest development. , 2019, Ecology.

[28]  K. Gadow,et al.  Is the reverse J-shaped diameter distribution universally applicable in European virgin beech forests? , 2006 .

[29]  Y. Paillet,et al.  Deadwood and tree microhabitat dynamics in unharvested temperate mountain mixed forests: A life-cycle approach to biodiversity monitoring , 2014 .

[30]  F. H. Bormann,et al.  Catastrophic disturbance and the steady state in northern hardwood forests , 1979 .

[31]  B. Commarmot,et al.  Age structure and disturbance dynamics of the relic virgin beech forest Uholka (Ukrainian Carpathians) , 2012 .

[32]  J. Heilmann‐Clausen,et al.  The structural dynamics of Suserup Skov, a near-natural temperate deciduous forest in Denmark , 2000 .

[33]  David A. Coomes,et al.  Mortality and tree‐size distributions in natural mixed‐age forests , 2007 .

[34]  D. Lieberman,et al.  Forests are Not Just Swiss Cheese: Canopy Stereogeometry of Non‐Gaps in Tropical Forests , 1989 .

[35]  J. Diaci,et al.  Regeneration patterns after intermediate wind disturbance in an old-growth Fagus-Abies forest in southeastern Slovenia , 2006 .

[36]  A. Watt,et al.  Pattern and process in the plant community , 1947 .

[37]  J. Paluch.  The spatial pattern of a natural European beech (Fagus sylvatica L.)–silver fir (Abies alba Mill.) forest: A patch-mosaic perspective , 2007 .

[38]  Erratum to: Spatial variability of close-to-primeval Fagus–Abies–Picea forests in the Western Carpathians (Central Europe): a step towards a generalised pattern , 2015, European Journal of Forest Research.

[39]  S. Levin.  The problem of pattern and scale in ecology , 1992 .

[40]  Martina L. Hobi,et al.  Validation of a classification protocol: meeting the prospect requirement and ensuring distinctiveness when assigning forest development phases , 2016 .

[41]  M. Schröter,et al.  Crown plasticity and neighborhood interactions of European beech (Fagus sylvatica L.) in an old-growth forest , 2011, European Journal of Forest Research.

[42]  David A. Coomes,et al.  Nationally Representative Plot Network Reveals Contrasting Drivers of Net Biomass Change in Secondary and Old-Growth Forests , 2017, Ecosystems.

[43]  T. Parpan,et al.  The hypothesis of the pulsed dynamics of virgin beech forests , 2009, Russian Journal of Ecology.

[44]  P. Meyer,et al.  Dead wood in European beech (Fagus sylvatica) forest reserves , 2005 .

[45]  C. Collet,et al.  Using competition and light estimates to predict diameter and height growth of naturally regenerated beech seedlings growing under changing canopy conditions , 2006 .

[46]  C. Gini.  Measurement of Inequality of Incomes , 1921 .

[47]  C. Leuschner,et al.  A novel empirical approach for determining the extension of forest development stages in temperate old-growth forests , 2018, European Journal of Forest Research.

[48]  A. Bončina.  Comparison of structure and biodiversity in the Rajhenav virgin forest remnant and managed forest in the Dinaric region of Slovenia , 2000 .

[49]  T. Vrška,et al.  Developmental phases in a temperate natural spruce-fir-beech forest: determination by a supervised classification method , 2010, European Journal of Forest Research.

[50]  M. Čurović,et al.  A comparative analysis of recent changes in Dinaric uneven-aged forests of the NW Balkans , 2014 .

[51]  J. Schütz.  Close-to-nature silviculture: is this concept compatible with species diversity? , 1999 .

[52]  B. Rudolf,et al.  World Map of the Köppen-Geiger climate classification updated , 2006 .

[53]  T. Nagel,et al.  Disturbance, life history traits, and dynamics in an old-growth forest landscape of southeastern Europe. , 2014, Ecological applications : a publication of the Ecological Society of America.

[54]  F. Biondi,et al.  Tree ring‐based metrics for assessing old‐growth forest naturalness , 2017 .

[55]  J. Paluch.  The stochastic backward shifts model better corresponds to the fine-scale structural heterogeneity of old-growth Abies-Fagus-Picea forests than the ontogenic life cycle model , 2021 .

[56]  S. Winter,et al.  Determination of a common forest life cycle assessment method for biodiversity evaluation , 2011 .

[57]  Gert-Jan Nabuurs,et al.  Natural disturbances in the European forests in the 19th and 20th centuries , 2003 .

[58]  E. Zenner,et al.  The dynamics of structure across scale in a primaeval European beech stand , 2015 .