HighDiv-SRC (Germany)

HighDiv-SRC is adopting the overall goal of tree diversity experiments to the applied realm of Short-Rotation Coppice plantations and their industrial applications. Hence, HighDiv-SRC aims to assess the effects of tree species diversity on various ecosystem functions and, ultimately, tree growth and yield stability (e.g. resistance to drought and pests) in short rotation coppice plantations. Particular focus is on ecosystem functions that are important for the assessment of ecological sustainability, such as water and nutrient use, carbon sequestration and biodiversity. The experiment was planted in Freiburg in spring 2015.

aerial view plantation
Location field trial (Freiburg)

The experiment follows a randomized block design with three replicates (blocks). Four species that are often used in commercial short-rotation plantations were planted in all theoretically possible combinations, i.e. plots with single species and mixtures of two, three and four species. Consequently, each block contains fifteen plots with different species combinations. Each plot contains nine subplots that will be used for specific assessments (e.g. litter decomposition, weed dynamics, soil biology). Planting density was about 15 600 ha-1.

design HighDiv-SRC experiment
Schematic view of the plantation with the 3 blocks (blue, red, green), plot numbers (Pl), and species (W: Salix, Ro: Robinia, Pau: Paulownia, Pap: Populus)

design HighDiv-SRC plots
Hexagonal planting design of monoculture, 2-species, and 3-species plots. In plots with three and four species, the species positions were randomized with the restriction that, within columns and lines, each individual had to be directly neighboured by an individual of a different species.

Site characteristics

location Freiburg
former land use grassland, sheep grazing
altitude 230 m
soil type Cambisol
area 0.4 ha
no of plots 45
plot size 9.6 m x 9.6 m
no of trees planted 6480
planting date spring 2015
diversity variables species richness
diversity gradient 1, 2, 3, 4 sp.
size species pool 4
species pool Paulownia tomentosa
Populus maximowiczii x trichocarpa
Robinia pseudoacacia
Salix schwerinii x viminalis 'Tora'
contact person Michael Scherer-Lorenzen

HighDiv-SRC tests the hypothesis that productivity and yield stability of bio-energy plantations can be enhanced by the use of appropriate species mixtures, and we attempt to quantify the effects of mixtures on ecosystem processes relevant to sustainability, e.g., nutrient cycling and carbon sequestration.
The research has implications for future bio-energy concepts, because new SRC plantations should comply with the sustainability requirements (e.g. biodiversity, C sequestration) for a carbon-neutral and environmentally friendly energy source.

Extra information
Send an e-mail to the contact person.

photo April 2016 photo July 2016
April 2016 July 2016