Subproject 3: Biodiversity

In this subproject, data on tree regeneration, biodiversity and ecosystem functions will be collected and the influence of ungulate predation and microclimate will be extracted from the data.

Work package 1: Tree regeneration and plant diversity

The regeneration surveys took place from 09.06.2020 to 05.07.2020 and from 29.08.2023 to 12.09.2023. Vegetation surveys were carried out inside and outside a fence, with two alignment poles forming a square. The alignment rods crossed each other to form a 4 m2 square. Woody plants were recorded by number of individuals, species and height class. Preliminary analyses indicate possible interactions between ungulate predation, microclimate and tree growth. The herbaceous plants will be recorded in June 2024.

Work package 2: Microclimate

On November 1, 2023, Tomst loggers (TMS standard) were installed in all 180 plots, as well as 15 data loggers (Lascar Electronics Multi Data Logger EL-USB-2) in a further 30 plots. These loggers measure air and soil temperature as well as soil moisture. The data is evaluated after one year. In addition, light availability and thermal images were measured to calculate the temperature heterogeneity on the subplots. These measurements will be repeated in June 2024 during the vegetation period.

Work package 3: Above- and below-ground biodiversity

Conducting a rapid assessment of above- and belowground biodiversity using random samples. The aboveground arthropods will be sampled from May to June 2024 using a suction device (STIHL SH 56/86) and sorted, weighed and identified in the laboratory using metabarcoding. The subterranean mesofauna and nematodes will be collected with soil cores in October 2024 and extracted at iDiv in Leipzig. They will also be weighed in the laboratory and identified using metabarcoding.

Work package 4: Ecosystem functions

Data on various ecosystem functions will be collected and investigated to determine whether they are influenced by ungulate browsing and microclimate. For the ecosystem functions of the soil, soil samples are taken and analyzed with O2 machines at iDiv. Respiration, microbial biomass, specific respiration quotients and water content will be analyzed.