Lange, OL/ Bruns-Strenge, S 1991: Photosynthetische Primärproduktion der Flechte Cladonia portentosa an einem Dünenstandort auf der Nordseeinsel Baltrum. II. Photosynthesedmodell: Entwicklung, Parametrisierung durch Messungen des CO2-Gaswechsels unter kontrollierten Bedingungen und Test [Photosynthetic primary production of the lichen Cladonia portentosa in a dune habitat at the Island Baltrum in the North Sea. II. A photosynthesis model: development, parametrization based on CO2 exchange measurement in the laboratory, and validation]. - Flora185: 214-232. [RLL List # / Rec.# 11015] Keywords: CO2 EXCHANGE/ PHOTOSYNTHESIS/ PRIMARY PRODUCTION
Abstract: 13 fig. 2 tab. ["Photosynthesis and dark respiration of the lichen Cladonia portentosa was studied under controlled conditions in the laboratory. There was good agreement with respect to the absolute rates of CO2 exchange as well as in response to single factors between the laboratory results and performance of the lichen in the field. The dependencies of CO2-gas exchange on incident photosynthetically active radiation, thallus temperature, and thallus-water content were described with a series of equations. These functions were combined in a general model which simulates net photosynthesis in response to all three environmental factors. The model was validated against observed diurnal courses of CO2 exchange which were obtained in the natural habitat of the lichen. Field performance is reproduced well by the model although deviations may occur in extreme environmental situations.]