Phytosociology, distribution and ecology of a willow community with false tamarisk from the Lotru Valley (Romanian Carpathians)

Abstract

The overall objective of this research was to contribute to a better knowledge of the phytosociology, ecology and distribution of the plant community formed by Myricaria germanica (false tamarisk) and the willow species Salix purpurea. This plant community has an important role in reducing the speed and strength of the water flow during floods. The description was based on cover-abundance data for the faithful, dominant, characteristic and companion species of this plant community. A predominance of Myricaria germanica was observed when analysing the phytocoenoses, as the species finds in this area favourable ecological conditions for an abundant development. Salix purpurea presents a small abundance-dominance or in some phytocoenoses may even lack. The field research also revealed the excessive development of the species Calamagrostis pseudophragmites in some areas, related mostly with the effect of human activities. The anthropogenic disorders have induced modifications in the floristic physiognomy and compositions of the phytocoenoses, favouring also the invasion of opportunistic species such as Ambrosia artemisiifolia, Impatiens glandulifera, Phytolacca amearicana, Amorpha fruticosa, Erigeron annuus, which continuously extend in the studied territory. As Myricaria germanica and Salix purpurea phytocoenoses suffer a great decline throughout Europe, the habitat built by these species was declared of interest and was included in the Habitats Directive.