COMPARISON OF THE HERB LAYER BIOMASS OF AN ORIGINAL AND A SECONDARY WILLOW-POPLAR FORESTS OF THE MORAVA RIVER

The contribution is dealing with comparison of the herb layer biomass and floristic changes of an original willow-poplar forest and secondar y poplar monoculture on the low stretch of the Morava river. An origin al willow-poplar forest (Solici-Populetum typicum) and a secondary pop lar monoculture with Populus canadensis, arisen on the original habita t after an artificial reforestation are analysed in detail. Changes in cover and biomass of the herb layer of above-mentioned communities ar e discussed as well as production and floristic changes caused by a hi gh flood in 1991.