Our unit aims to improve understanding of 1) spatial patterns and temporal trends of atmospheric deposition of nitrogen, sulphur, phosphorus, and base cations, 2) the effect of changing acid deposition on soil acidification, 3) the impact of changing nutrient deposition on nutrient balance in forest ecosystems, and 4) the interactions of nutrient and acid deposition with other global changing factors, including climate warming, drought, increasing CO2 and ozone concentrations. This is crucial to improve the ecological resiliency of natural and planted forests, and to better guide management options. 

Atmospheric nitrogen and sulphur deposition has been globally altered by anthropogenic emissions and has aroused various concerns regarding its ecological impacts. For instance, nitrogen deposition, particularly in oxidized forms, has recently decreased in European countries and the U.S., while it is increasing rapidly in other countries with burgeoning populations and economies (e.g., China and India). Moreover, atmospheric deposition of phosphorus and base cations have also been increased by anthropogenic emissions at regional scales. Abiotic factors such as climate, increase in surface ozone, along with biotic factors such as insect outbreaks, disease, and invasive species are altering forest structure and function in the 21st Century. We thus focus on the joint effects of these factors on the balance of nutrient cycles and the health of forest ecosystems in different climate zones through a variety of monitoring, modelling and experimental efforts.