Seasonal variation of LAI in Swedish coniferous forest

Abstract: Leaf Area Index (LAI) is quantity representing the amount of foliage in the canopy, which makes it an important parameter for analysing terrestrial ecosystems. Traditional methods of measuring LAI were done by analysing hemispherical photographs by hand and were very time consuming, requiring specific weather conditions (Jonckheere et al. 2004). Modern methods, including remote sensing, have much higher automation, yielding continuous data. In this thesis, LAI for a spruce forest at Hyltemossa ICOS site was calculated and plotted as a continous time series, and the results were compared to available discontinuous measurements done using hemispherical photographs, as well as other studies of LAI for coniferous forests. The resulting values showed no seasonal or multiannual trend, but generally match the findings of several other studies, with the obtained values between 4 and 5 being typical for coniferous forest (Parker 2020).