Berggren Kleja, Dan
- Department of Soil Sciences, Swedish University of Agricultural Sciences
- Royal Institute of Technology (KTH)
Research article2008Peer reviewed
Svensson, Magnus; Jansson, Per-Erik; Kleja, Dan Berggren
The change of current pools of soil C in Norway spruce ecosystems in Sweden were studied using a process-based model (CoupModel). Simulations were conducted for four sites representing different regions covering most of the forested area in Sweden and representing annual mean temperatures from 0.7 degrees C to 7.1 degrees C. The development of both tree layer and field layer (understory) was simulated during a 100-year period using data on standing stock volumes from the Swedish Forest Inventory to calibrate tree growth using different assumptions regarding N supply to the plants. The model successfully described the general patterns of forest stand dynamics along the Swedish climatic transect, with decreasing tree growth rates and increasing field layer biomass from south to north. However, the current tree growth pattern for the northern parts of Sweden could not be explained without organic N uptake and/or enhanced mineralisation rates compared to the southern parts. Depending on the assumption made regarding N supply to the tree, different soil C sequestration rates were obtained. The approach to supply trees with both mineralised N and organic N, keeping the soil C:N ratio constant during the simulation period was found to be the most realistic alternative. With this approach the soils in the northern region of Sweden lost 5 g C m(-2) year(-1), the soils in the central region lost 2 g C m(-2) year(-1), and the soils in the two southern regions sequestered 9 and 23 g C m(-2) year(-1), respectively. In addition to climatic effects, the feedback between C and N turnover plays an important role that needs to be more clearly understood to improve estimates of C sequestration in boreal forest ecosystems.
boreal; carbon; CoupModel; climate; nitrogen; organic nitrogen uptake
Biogeochemistry
2008, Volume: 89, number: 1, pages: 95-119
Publisher: SPRINGER
Renewable Bioenergy Research
Environmental Sciences related to Agriculture and Land-use
DOI: https://doi.org/10.1007/s10533-007-9134-y
https://res.slu.se/id/publ/18628