Improved methods formeasuring forest landscape structure: LiDAR complements field-based habitat assessment

Journal: Biodiversity and Conservation

Authors:

Florian Zellweger (corresponding author)

Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland

Tel: +41 44 7392 821, Fax: +41 44 7392 215, e-mail:

Felix Morsdorf

Departement of Geography, University of Zurich - Irchel, Winterthurerstrasse 190, 8057 Zürich, Switzerland

Ross S. Purves

Departement of Geography, University of Zurich - Irchel, Winterthurerstrasse 190, 8057 Zürich, Switzerland

Veronika Braunisch

Conservation Biology, Institute of Ecology and Evolution, University of Bern, Baltzerstrasse 6, 3012 Bern, Switzerland

Forest Research Institute of Baden-Württemberg, Wonnhaldestrasse 4, 79100 Freiburg, Germany

Kurt Bollmann

Swiss Federal Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, 8903 Birmensdorf, Switzerland

Online Resource 1Description and definition of field variablesused to quantify habitat characteristics, including the sampling reference within the sampling plot (30 x 30 m) (Fig. 1c)

Variable / Definition / Operationalisation/Unit / Sampling reference
Stand characteristics
Successional stage / Classification of the dominant stand's successional stage based on tree height (h) and diameter at breast height (dbh, at 1.3 m above ground) distributions (Keller 2005). / 1 = regeneration (h ≤1.3 m), 2 = thicket (h ≥1.3 m, dbh ≤10 cm), 3 = pole stage (dbh 11-30 cm), 4 = tree-stage (dbh 31-60 cm), 5 = old forest (min. 3 trees with dhb ≥61 cm , 6 = multi-age forest / Plot (30 x 30 m)
Stand structure / Classification of the vertical stand structure based on the proportion of different layers (Keller 2005), multi-layered includes 'stufig' and 'Rottenstruktur'. / 1 = one-layered 2 = two-layered 3 = multi-layered/tree-layered / Plot (30 x 30 m)
Canopy cover / Area covered by crowns of trees (h ≥5 m) / Estimated in %-steps: 0, 1, 5, 10, ..., 95, 100 / Each quarter (15 x 15 m) separately, averaged
Shrub cover / Area covered by shrub layer (h = 1.3 - 5 m) / Estimated in %-steps: 0, 1, 5, 10, ..., 95, 100 / Each quarter (15 x 15 m) separately, averaged
Stand composition
Canopy composition / Proportion of each species within the tree layer (h ≥5 m) based on stem counts: Spruce (Picea abies), Fir (Abies Alba), Pine (Pinus sylvestris & Pinus cembra), Larch (Larix decidua), other conifers, Beech (Fagus sylvatica), resource trees (Sorbus sp., Salix sp., Betula sp., Alnus sp., Corylus sp., Sambucus sp.), other deciduous trees / Estimated in %-steps: 0, 1, 5, 10, ..., 95, 100 / Plot (30 x 30 m)
Shrub composition / Proportion of each species within the shrub layer (1.3 m≤ h ≤5 m) based on stem counts of species listed in Canopy composition. / Estimated in %-steps: 0, 1, 5, 10, ..., 95, 100 / Plot (30 x 30 m)
Ground vegetation
Ground vegetation cover / Area covered by ground vegetation (h ≤1.3 m); includes all ferns, grasses, herbs, Rubus sp., Vaccinium sp. Rhododendron sp., Juniperus sp. / Estimated in %-steps: 0, 1, 5, 10, ..., 95, 100 / Ground vegetation plots 1 and 3 (7.5 x 7.5 m), averaged
Ground vegetation distribution / Classification of the spatial distribution of ground vegetation / 1 = clumped (vegetation restricted to one side of the plot), 2 = patchy (vegetation restricted to two large patches), 3 = evenly (several small patches, evenly distributed) / Plot (30 x 30 m)
Cover of coniferous regeneration / Relative proportion covered with coniferous regeneration / Estimated in %-steps: 0, 1, 5, 10, ..., 95, 100 / Ground vegetation plots 1 and 3 (7.5 x 7.5 m), averaged
Cover of deciduous regeneration / Relative proportion covered with deciduous regeneration / Estimated in %-steps: 0, 1, 5, 10, ..., 95, 100 / Ground vegetation plots 1 and 3 (7.5 x 7.5 m), averaged
Cover of herbs / Relative proportion covered with herbs / Estimated in %-steps: 0, 1, 5, 10, ..., 95, 100 / Ground vegetation plots 1 and 3 (7.5 x 7.5 m), averaged
Cover of ferns / Relative proportion covered with ferns / Estimated in %-steps: 0, 1, 5, 10, ..., 95, 100 / Ground vegetation plots 1 and 3 (7.5 x 7.5 m), averaged
Cover of grass / Relative proportion covered with grasses / Estimated in %-steps: 0, 1, 5, 10, ≤..., 95, 100 / Ground vegetation plots 1 and 3 (7.5 x 7.5 m), averaged
Cover of berries / Relative proportion covered with berries / Estimated in %-steps: 0, 1, 5, 10, ≤..., 95, 100 / Ground vegetation plots 1 and 3 (7.5 x 7.5 m), averaged
Ground vegetation height / Height of dominant ground vegetation / Measured in cm / Ground vegetation plots 1 and 3 (7.5 x 7.5 m), averaged
Resources/Functional trees
Total Rowans / Number of Rowans (Sorbus aucuparia), h ≥3 m / Counted number / Nested square (15 x 15 m)
Rowans fruiting / Number of fruiting Rowans (h ≥3 m) / Counted number / Nested square (15 x 15 m)
Basal-branched trees / Number of basal branched trees or groups of trees, i.e. trees (h ≥5 m) with branches reaching down to 50 cm or lower above ground / Counted number / Plot (30 x 30 m)
Ant hills / Total number of ant hills / Counted number / Nested square (15 x 15 m)
Ecotones
Ecotones / Presence/absence and number of ecotones / E1=inner forest edge, E2=outer forest edge, E3=between successional stage, E4=along waterbodies, E5=along forest roads, E6=other / Plot (30 x 30 m)