Optimization of carbon uptake in south Sweden’s spruce forests

The overall aim of the project is to determine how the net ecosystem productivity (NEP) varies with stand age of spruce forests in southern Sweden that are managed with rotation forestry system. Information on the relationship between NEP and stand age is crucial for determining the time when optimal carbon uptake is reached, which affects the time of final felling. This knowledge is important to be able to make decisions about how the forest should be managed in order to best contribute to achieving our national climate goals. Other goals for the project are to quantify net primary production for tree and ground vegetation layers as a function of stand age and soil respiration as a function of stand age, soil and abiotic factors. The estimation of the NEP is to be made through measurements of net primary production in trees, soil vegetation and soil fungi as well as of heterotrophic respiration in 12 stands of spruce of mean site productivity in a limited area in southern Sweden with a similar climate. The methodology used is based on biometrics for the tree layer, soil sampling with lab analyses, ingrowth bags for soil fungi and fine roots and gas exchange measurements from soil and ground vegetation in root-isolated and intact sample areas. Solar radiation, soil temperature and humidity and air temperature will be measured continuously in all stands. Stands in the age range 0 – 120 years will be selected so that an age interval of approx. 10 years is obtained. The results will be published both in peer-reviewed journals as well as in other types of media with, among other things, a focus on forestry. Communication of the results to stake holders will take place through participation in activities at Lund University specially set up for this purpose. The project group has very good competence and experience in forests, soils, greenhouse gases, dendrochronology, climate and measurement methods.