Soil condition survey in the forest (BZE)

The soil forms the central part of the biological cycle of the forest. Therefore, particular attention must be paid to changes in this complicated system. For this reason, in 1989, the Minister for the Environment, Spatial Planning and Agriculture commissioned the State Institute for Ecology, Soil Planning and Forest Planning, LÖLF (now: State Institute for Ecology, Soil Regulation and Forestry/Landesamt für Agrarordnung, LÖBF/LAfAO) as well as the Geologische Landesamt NRW, GLA NRW (now: Geological Service NRW — Landesbetrieb, GD NRW), to investigate the current soil chemical status of our forest soils nationwide. This soil condition survey in the forest (BZE) is intended to include: — record and evaluate the current soil chemical status of our forest soils — Elucidate links between soil status and forest damage — ensure better transferability of results from forest damage research to larger forest areas — Identify dangers arising from the current state of soil for the current forest populations and the next generation of forests — Provide information on the planning and implementation of soil conservation and improvement measures — Provide information on the assessment of risks to the quality of groundwater and spring water. The Geologische Landesamt NRW carried out the site work on the BZE between 1989 and 1992. In order to find the links between soil chemism and forest damage, the soils were examined at sites where forest damage is also assessed annually. Sampling took place in the 4 x 4-km grid, i.e. the forested area in the country area was divided into a square grid of 4 km side length each. In each grid square, a study spacer was selected. In each of the 498 test areas, — the floors exactly mapped — Ground excavations — the soil characteristics and properties described in detail — Samples taken from seven to ten depth levels for chemical and physical analyses. A total of around 3,800 soil samples (area mixing samples) were collected for analysis; another 590 samples are planned for radiological examinations. The geochemical laboratory of the Geological Service NRW has now completed the analysis for an 8 x 8 km grid of the nationwide BZE. The results for the considerably denser 4 x 4-km grid were also presented in mid-1995. Modern measurement methods, which are coordinated with the laboratories of the other federal states, guarantee accurate and comparable results throughout Germany.