Monitoring

ICP Forests works at two monitoring levels. 

Level I: Active participating countries gather data on crown condition of forest trees on about 6,000 plots every year. In addition, they examine forest soils approximately every 10-15 years and measure the nutrient balance of trees. This is called the Level I monitoring.

Level II: Since 1995, intensive Level II monitoring has also been carried out on more than 600 plots across Europe. The surveys cover air quality and visible ozone damage, atmospheric deposition, soil and soil water chemistry, weather conditions, ground vegetation, tree growth, phenology, litterfall, and foliar chemistry. Level II monitoring aims at identifying the influence of air pollutants and climate change on the condition of forest ecosystems and their spatial and temporal changes.