Federal-State Working Group on Forest Environmental Monitoring

The nationwide forest environmental monitoring program in Germany is a coordinated system comprising repeated, extensive grid-based inventories (Soil and Forest Condition Survey, Level I) and intensive forest environmental monitoring (Level II). The surveys are conducted in close cooperation with the federal states and are overseen by the Federal-State Working Group on Forest Environmental Monitoring.

The WZE and Level II are also covered under the ForUm Regulation. Further information on this can be found in the Implementation Concept for Forest Environmental Monitoring in Germany (German language).

As part of the nationwide Soil Condition Survey (BZE), we examine the condition and changes in forest soils, vegetation, canopy condition and forest nutrition at approximately 1,900 sampling points in Germany. These points are located on an 8x8 km grid within the forest. In 2006, sampling for the European Soil Condition Survey (BioSoil) took place on a sub-sample within a 16x16 km grid. These are also sampling points for the Forest Condition Survey (WZE). The BZE employs harmonized methods for sampling and analysis across federal states, which are published in a set of guidelines. The BZE is a joint project of the federal government and the federal states. BZE III (2022 to 2024) is currently underway and the federal report is expected to be available by the end of 2028. An overview of the results of the second BZE (2006 to 2008) is available here (German). BZE I was conducted from 1987 to 1993.

Intensive forest environmental monitoring (Level II) also examines conditions and trends within the forest ecosystem. At nearly 70 selected sites, atmospheric pollutant inputs, tree growth, crown condition, and nutritional status, as well as soil solution composition are continuously recorded and supplemented by surveys of weather conditions, the species composition of ground vegetation (biodiversity) and litterfall. Our analyses show for example how tree growth and crown condition influence each other. We also investigate how increased pollutant inputs from traffic and agriculture, as well as climate change, affect vegetation growth.