Verdwijnen (2017 Web-Dl Uploaded For Free Public Full
Verdwijnen (2017 Web-Dl Uploaded Full Dendrometric Surveys

It contains over 400 ha of old beech stands (200 years ol d) and more than 25,000 VLT, mainly beech ( Vandekerkhove et al., 2011 ). It c an theref ore be c onsidered on e of the most important ho tspots for VLT in Northwestern Europe.

The spatial distribution pattern of the trees is considered regular when the value of R is significantly larger than 1.

Description of the forest stand at the study site (bold) and the eight comparison sites that were used to pair with the studied stande Figures - uploaded by Kris Vandekerkhove Author content All figure content in this area was uploaded by Kris Vandekerkhove Content may be subject to copyright.

Verdwijnen (2017 Web-Dl Uploaded For Free Public Full

Discover the worlds research 20 million members 135 million publications 700k research projects Join for free Public Full-text 1 Content uploaded by Kris Vandekerkhove Author content All content in this area was uploaded by Kris Vandekerkhove on Jul 30, 2018 Content may be subject to copyright.

W e analyzed the charac teristics of very large trees in one of the few stands of lowland o ld-growth beech fores t in Nort hw estern Europe, regenerated around 1775 and left unmanaged since 1986.

Verdwijnen (2017 Web-Dl Uploaded Full Dendrometric Surveys

We examined their density, diameter range, increm ent, mortality rate and spatial distribution, based on repeated full dendrometric surveys.

In order to evaluate the results, we compared them to original datasets from primary a nd s econdary old-growth beech forests in Europe, and an extensive reference table, compiled from inventories and literature.

In our study s ite, the density of very lar ge trees increas ed from 31.5 to 34.3 trees ha -1 over the last 25 years, reaching a m edian DBH of 97 cm (mean 98.

DBH of 159 cm.

Although the trees were over 240 years old, they still showed an average DBH increment of 4.75 mm.year -1 and a low mortality rate ( 0.89.year -1 ), indicating that they we re still vital.

Thes e figures are remarkably high compared to other old- growth beech f orest reference sites, where the densit y of ver y large trees generally varies between 5 and 20 trees ha -1 (m edian value 1 3.1 ), with a median diameter of 85 to 90 cm and maximum DBH for beech trees rarely exceeding 100 to 130 cm.

The regular s patial distribution pattern of the very larg e trees in the studied stand c learly differed from a t ypical old-growth stand, in which very large trees are randomly distributed.

Over the last 25 years though, because of random mortality and ingrowth, the spatial distribution gra dually became more random.

The extraordinary densities and sizes of the ver y large trees in our study sit e can be explained b y the favorable climate and site conditions that promote high increments, in combination with the former management interventions of tending and thinning that res ulted in continuous non-suppressed growth.

Although derived from a very sp ecific case with particular conditions, our observations m ay be relevant to other beech fores ts, as they tend to reset certain baseline ass umptions for tree size and longevi ty potential of beech in Northwestern Europe.

Keywords: very large trees, old-growth forest, Fagus sy lvatica, increment, mortality, spatial distribution pattern.

Already in ancient t imes, VLT were m issing in lowland E uropean forests managed for wood production (e.g.

Vandekerkhove et al., 2009, 2011).

They only occurred in hunting reserv es, deer parks and wood pastures.

In m any regions their n umbers are still declining (Lindenm ayer et al., 2012) although in other areas, the y are more and more protected and integrated in forest managem ent as their recreational and ecological value is better known and appreciated (e.g.

Fedrowitz et al., 2014; Gustafsson et al., 2012).

Still, the numbers of V LT are low.

In Germany, the dens ity of VLT in forests was 66 per 100 ha in 2012 (T hnen-Institut, 2017), an increase of 50 compared to 2002 (Kroiher and Bolte, 2015).

In northern Belgium, a similar density of 65 VLT per 100 ha was registered (Vandekerkhove et al., 2011).

In Switzerland, VLT density is somewhat higher, with 120 VLT per 100 ha in the beech-dom inated colline and subm ontane height range, twic e as high as durin g the previous survey ten years before (Brndli et al., 2010).

VLT f ulfill a wide range of ecosystem services.

They occupy a revered position in the human psyche (Lindenmayer, 2016), and specif ic aesthetic, social and cultural values are assigned to them (Blicharska and Mikusinski, 2014 ).

Several studies indicated that the general public has a clear preference for forest landscapes and stands containing large trees and this preference increases with increasing tree size and ad vancing stage of stand devel opment, thus representing a higher recreational value (e.g.

Edwards et al., 20 12; Gunders en and Fr ivold, 2008; Ribe, 1989).

Finally, VLT also have a major influence o n hydrological regimes, nutrient c ycles (Lindenmayer, 2016) a nd carbon sequestration.

We analyzed the presence and c haracteristics (density, diam eter range and increm ent, mortality r ate and spatial distribution) of VLT in one of the r are old -growth beech forest stands in the lowlands of Northwestern Europe, over a time period of 25 years.

F inally, we s upplemented the stud y and comparison sites with literature data in a comprehensive reference t able on VLT in old-growth beech f orests in Europe.

It contains over 400 ha of old beech stands (200 years ol d) and more than 25,000 VLT, mainly beech ( Vandekerkhove et al., 2011 ).

It c an theref ore be c onsidered on e of the most important ho tspots for VLT in Northwestern Europe.