Effects chain – Example presentation from the ‘woodland and forestry’ act | Umweltbundesamt

Climate changes relevant to the action field

State: Heat and Drought

In Germany, the annual mean precipitation has increased since 1881 in respect of the total surface area mean measured for the country. There are, however, distinct regional and seasonal differences. Overall, the rainfall mean has remained largely unchanged in summer, whereas particularly in winter, conditions have become significantly more humid. However, these minor changes in mean precipitation values should not be misunderstood as signifying that there are no phases where extreme water shortages occur regionally. Soils can dry out whenever the evaporation in summer increases as a result of high temperatures. Since the ‘summer of the century’ in 2003, such dry phases in summer have occurred frequently, resulting in soils drying out severely and to considerable depths (cf. Extreme Drought).

Impacts of climate change

Impact: FW-I-6 Endangered spruce stands

Many trees suffer from diminished vitality caused by climate-related changes, especially during the increasing summer droughts, while thermophilic insects can benefit from such conditions. Bark beetles such as the European spruce bark beetle (Ips typographus) and the six-dentated bark beetle (Pityogenes chalographus) breed – for instance after windthrow – in newly dead timber or by penetrating the bark of trees weakened by heat and drought. In warm years, they can produce up to six generations thus leading to major infestation pressures.

Impact: FW-I-5 Damaged timber -extrent of random use

After periods of storm, heat, drought and infestation with insect pests, it is essential to remove – at least partially – newly dead trees from any affected areas in order to facilitate reforestation as soon as possible and to reduce the breeding spaces available to insect pests. During and after recent drought years, arbitrary use accounted for almost three quarters of the annual logging total in Germany’s forests. The work involved tied up considerable capacities in the forestry sector, which would in fact have been required for implementing forest transformation measures.

Adaptations – activities and results

Reponse: FW-R-1 Financial support for forest transformation

The transformation of forests by creating climate-resilient stands has become the most important forestry strategy. The transformation objective targets the composition of tree species which are able to cope better with changing site conditions and climatic conditions as well as maintaining well-structured stands. State forest entities have for years made massive investments in forest transformation. In the field of privately-owned forests, and forests owned by corporate entities, the funding opportunities available have been expanded too, the purpose being to catch up on the rehabilitation of vast areas of calamity forest.