Vortragsreihe Ökologie und Umweltforschung WS 2014/15

Open-field warming experiments in a mature deciduous broadleaf forest at Takayama, Japan

Prediction of the changes in carbon balance in forest ecosystems under climate change is one of the urgent and challenging researches in environmental sciences. To achieve better prediction of the possible impacts of the global warming on forest carbon balance, ecophysiological understandings on photosynthetic carbon gain and respiratory carbon release should be gained.

In a cool-temperate deciduous broadleaf forest in ‘Takayama’ site (AsiaFlux, JaLTER), located on a mountainous landscape in central Japan, multidisciplinary research on forest carbon balance is taking place, including micrometeorological measurements of CO₂ flux, ecological processes of tree growth and soil carbon sequestration, leaf ecophysiological research on canopy photosynthesis and phenology, their integration by model analysis, and in situ and satellite remote sensing of canopy photosynthetic productivity by combining canopy ecophysiological and optical measurements.

We established an open-field warming experiment for foliage on a canopy tree species in 2011 and for soil in 2012, to examine the photosynthetic and respiratory responses to warming, respectively. Artificial warming on foliage resulted in earlier leaf bud-break and delayed leaf senescence, and higher leaf photosynthetic capacity. Soil warming resulted in higher soil respiration rate but its temperature response curve changed with the smaller slope in warmed soil. Model simulations for our broadleaf forest showed that higher temperature would increase canopy and understory photosynthesis by prolonged leaf longevity and snow-free season, respectively.

***

Invited by John Tenhunen, Plant Ecology.

• Announcement as PDF