Universitat fur Bodenkultur Wien University of Natural Resources and Life Sciences Vienna Department of Forest-and Soil Sciences Forest management and nutrient cycling ll Determination of nutrient balances Klaus Katzensteiner Institute of Forest Ecology,BOKU Vienna October 28-29,2013,College of Forestry,Northwest A&F University,Yangling,China 出
Forest management and nutrient cycling II Determina4on of nutrient balances Klaus Katzensteiner Ins.tute of Forest Ecology, BOKU Vienna October 28-29, 2013, College of Forestry, Northwest A&F University, Yangling, China Universität für Bodenkultur Wien University of Natural Resources and Life Sciences Vienna Department of Forest- and Soil Sciences
Terrestrial ecosystems at the interface between spheres Inner cycle Atmosphere Outer cycle Biogeochemical cycle Biosphere Pedosphere Hydrosphere Geosphere Lithosphere
Terrestrial ecosystems at the interface between spheres Atmosphere Hydrosphere Lithosphere Biosphere Pedosphere Geosphere Inner cycle Outer cycle Biogeochemical cycle
A simple system approach:ecosystem as an open system>matter and energy exchange at the interface to neighboring systems Input Input Vegetation The system agueyp Stock change may be divided into subsystems Soil Output Output Mass-and enegy flows connect system elements and the system with the environment
A simple system approach: ecosystem as an open system à maMer and energy exchange at the interface to neighboring systems Input Output Stock change Input Output Vegeta.on Soil Stock change The system may be divided into subsystems ... Mass- and enegy flows connect system elements and the system with the environment
Nutrient accounting in Forest ecosystems: Account balance over time t:B(t)=lin*At-lout*At I...Flux rate B(t)=0→steady state B(t)≠O:→stock change
Nutrient accoun4ng in Forest ecosystems: Account balance over .me t: B(t) = Iin *Δt- Iout *Δt I … Flux rate B(t) = 0 à steady state B(t) ≠ 0: à stock change
Nutrient balance models- a management tool? △nutrient stock(N) input from the atmosphere(deposition) +biological fixation fertilization losses with seepage - denitrification losses with harvest
Nutrient balance models – a management tool? Δ nutrient stock (N) = input from the atmosphere (deposi4on) +biological fixa4on + fer4liza4on - losses with seepage - denitrifica4on - losses with harvest