1. Population selection
Within ACORN, over 120 oak populations are investigated in Central and South-eastern Europe. WP1 will coordinate the selection of study populations, as well as the coordination and execution of field sampling to ensure a balanced and uniform sampling design.
The site selection criteria are based on environmental conditions, species composition, geographic distribution, and the historical and current impact of land-use. The project will make use of publicly accessible databases on site conditions, habitat, soil, and vegetation maps, as well as national expert knowledge.
An important criterion for population selection is autochthony, which means that all sampled trees occur naturally and evolved over many generations under the local site conditions and that the genetic population structure has not been significantly altered by humans (e.g. using non-native seeds and plants for reforestations).
Although species specific habitat preferences exist between the three ACORN oaks, they possess a broad environmental amplitude and grow under arid to moist site conditions.
The pictures show two sessile oak stands near Staufen (Germany), which are in immediate vicinity. The left picture shows the arid site, while the moist plot is shown on the right.
To establish selection criteria regarding site conditions, species composition (prior to sampling) and geographic distribution
To develop a representative sampling design between regions and among species
To identify pairs of closely situated populations on an arid and a moist site
To collect acorns for the establishment of a common-garden trial in WP4
ACORN sampling design
Coordination: AUTh (lead), FVA (co-lead)