A semi-empirical model of boreal-forest gross primary production, evapotranspiration, and soil water - calibration and sensitivity analysis

• Main Authors: Peltoniemi, Mikko, Pulkkinen, Minna, Aurela, Mika, Pumpanen, Jukka, Kolari, Pasi, Makela, Annikki
• Other Authors: Department of Forest Sciences, Department of Physics, Viikki Plant Science Centre (ViPS), Ecosystem processes (INAR Forest Sciences), Micrometeorology and biogeochemical cycles, Forest Ecology and Management, Forest Modelling Group
• Format: Article in Journal/Newspaper
• Language: English
• Published: Finnish Environment Institute 2016
• Subjects: SCOTS PINE FOREST; NET ECOSYSTEM EXCHANGE; LONG-TERM MEASUREMENTS; LIGHT-USE EFFICIENCY; CARBON BALANCE; STOMATAL CONDUCTANCE; CONIFEROUS FORESTS; CANOPY CONDUCTANCE; SOUTHERN FINLAND; SEASONAL COURSE; 4112 Forestry; 114 Physical sciences; 1172 Environmental sciences; Boreal Environment Research
• Online Access: http://hdl.handle.net/10138/165217

Simple approaches to predicting ecosystem fluxes are useful in large-scale applications because existing data rarely support justified use of complex models. We developed a model of daily ecosystem gross primary production (P), evapotranspiration (E), and soil water content (theta), which only requires standard weather data and information about the fraction of absorbed radiation. We estimated the parameters of the model for two boreal Scots pine eddy-covariance sites (Hyytiala and Sodankyla). The model predicted P and E adequately for Hyytiala for both calibration and additional test years. The model calibrated for Hyytiala slightly overestimated P and E in Sodankyla, but its performance levelled with the model calibrated for Sodankyla in a dry year. Sensitivity analysis of the model implied that drought prediction is sensitive, not only to key E submodel parameters, but also to P submodel parameters. Further improvement and calibrations of the model could benefit from forest sites with varying canopy and different species structures. Peer reviewed