Spatial diversity of forest regeneration after catastrophic wind in northeastern Poland

Abstract

We examined the spatial diversity of young growth established after the catastrophic windthrow occurred in 2002 in the northeastern part of Poland. Our observations and measurements were conducted on permanent circular measurement plots located in the Szast Protected Forest (continental lowland temperate forests) that were established 3 years after the windstorm and left to natural succession. We evaluated the spatial indices characterizing the four main aspects of stand structure: the spatial arrangement of seedlings and saplings, species mingling, tree size diversity at the local spatial scale and the overall structural complexity index. The calculations were conducted in parts of the forest with differing severity of disturbance. The obtained results indicated the prevalence of a random arrangement of young growth. Clumps of regeneration were observed to a lesser degree in all parts of the forest. The species diversity was moderate and was the highest in the slightly or severely disturbed stands. Scots pine formed homogenous groups of regeneration and oaks were intermingled among other tree species. The height of the natural regeneration was moderately or highly differentiated in all stands. The overall structural diversity index showed that stand regeneration in the slightly or moderately disturbed stands was more differentiated than the young growth in the severely disturbed stands. The size differentiation of young growth is a long-lasting process and thus should be considered in practices aimed at the re-growing of areas after a natural disturbance. This process might be used to the replace monocultures with more diversified forests even in poor forest site types.

Damage Diversity as a Metric of Structural Complexity after Forest Wind Disturbance

“…Meigs and Keeton [30] did not quantitatively relate complexity to severity; they did, however, note that the intermediate-severity wind disturbance can augment structural complexity. Since these interesting trends reported in previous work [28,30] do not employ damage diversity in their calculations of structural complexity, there could be a variety of components of complexity that are maximal at intermediate levels of wind damage severity.…”

“…Therefore, considering damage diversity as a component of multidimensional concepts of structural complexity, it may be expected that structural complexity overall may also show a peak at intermediate levels of damage severity, at least after wind disturbances. At least three previous studies have examined structural complexity after wind disturbances [28][29][30]. Szmyt and Dobrowolska [28] specifically reported higher structural complexity in intermediate-severity sites, although their metrics did not include damage diversity.…”

“…At least three previous studies have examined structural complexity after wind disturbances [28][29][30]. Szmyt and Dobrowolska [28] specifically reported higher structural complexity in intermediate-severity sites, although their metrics did not include damage diversity. Meigs and Keeton [30] did not quantitatively relate complexity to severity; they did, however, note that the intermediate-severity wind disturbance can augment structural complexity.…”

Windstorm disturbance triggers multiple species invasion in an urban Mediterranean forest

“…Evidence of windstorm damages to forest ecosystems is widely reported for North America (Frelich & Lorimer 1991, Peterson 2000 and Tropics (Vandermeer & De La Cerda 2004, Murphy et al 2008, while reports for Europe (Jonikavičius & Mozgeris 2013, Szmyt & Dobrowolska 2016 and the Mediterranean region are more rare, as related to the lower occurrence and intensity of extreme events. However, windstorm frequency and impact in Mediterranean forests have been increasing since the midtwentieth century, putatively due to climate change and forest management activities (Diodato et al 2011, Dupont et al 2015.…”

Challenges for Uneven-Aged Silviculture in Restoration of Post-Disturbance Forests in Central Europe: A Synthesis

“…On the other hand, birch (Betula pendula Roth) much more effectively restrains climax tree species [100] and often needs to be removed during later successional stages, if not selected as a crop tree. Natural stands that develop on disturbed areas are horizontally and vertically irregular and sparsely stocked [111]. For this reason, and for retaining collective stability in post-disturbance young stands, situational tending [81] may be a better approach than traditional tending with high densities of crop trees.…”