Flooded meadow communities an analysis of their productivity in a wet year

Abstract

The productivity of three plant communities differeing in moisture conditions was studied in the river basin of the Dyje near the village of Lanžhot (Southern Moravia). The communities were as follows:Serratuleto-Festucetum commutataeBalatova-Tulackova 1963,Gratiola officinalis—Carex praecox-suzae subass.Galium borealeBalatova-Tulackova 1963, andGratiola officinalis—Carex praecox-suzae subass.Rorippa silvestrisBalatova-Tulackova 1963. The associationGratiola officinalis—Carex praecox-suzae subass.Galium boreale appeared as the most productive one, its biomass maximum W=400 g . m−2 and the maximum R=0.042 g . g−1 . day−1 C=4.84 g . m−2 . day−1. Owing to extreme moisture conditions in the year 1966, the associationSerratuleto-Festucetum commutatae was also highly productive, as it reached the following maximum of dry matter production: 240 g . m−2, R=0.0388g . g−1 . day−1 C=4.64 g . m−2 . day−1. The maximum value of dry matter in the associationGratiola officinalis—Carex praecox-suzae subass.Rorippa silvestris was 220 g.m−2. Changes in dry matter production of shoots were evaluated statistically. The dry matter in the underground parts of plants in 1 square metre, collected from the 0–25 cm layer varied from 1,000 to 2,000 g.m−2. Together with records of the increasing dry matter in the shoots the author kept records of the properties of dead material.