Leaf area controls on energy partitioning of a temperate mountain grassland A. Hammerle, A. Haslwanter, U. Tappeiner, A. Cernusca, and G. Wohlfahrt Institut für Ökologie, Universität Innsbruck, Sternwartestr. 15, 6020 Innsbruck, Austria
Abstract. Using a six year data set of eddy covariance flux measurements of sensible
and latent heat, soil heat flux, net radiation, above-ground phytomass
and meteorological driving forces energy partitioning was investigated at a
temperate mountain grassland managed as a hay meadow in the Stubai Valley
(Austria). The main findings of the study were: (i) Energy partitioning was
dominated by latent heat, followed by sensible heat and the soil heat flux;
(ii) When compared to standard environmental forcings, the amount of green
plant matter, which due to three cuts varied considerably during the
vegetation period, explained similar, and partially larger, fractions of the
variability in energy partitioning; (iii) There were little, if any,
indications of water stress effects on energy partitioning, despite
reductions in soil water availability in combination with high evaporative
demand, e.g. during the summer drought of 2003.
Citation: Hammerle, A., Haslwanter, A., Tappeiner, U., Cernusca, A., and Wohlfahrt, G.: Leaf area controls on energy partitioning of a temperate mountain grassland, Biogeosciences, 5, 421-431, doi:10.5194/bg-5-421-2008, 2008.