PLANT-COMMUNITIES AND LIFE FORMS OF THE S UPERPARAMO OF THE SIERRA-NEVADA DE MERIDA NATIONAL-PARK, VENEZUELA

The vegetation of the superparamo of the ''Sierra Nevada de Merida'' N ational Park, Venezuela, was analysed using phytosociological methods. Thirteen plant communities are described, each with its characteristi c floristic and life form composition, structure, ecology and distribu tion. A new graphic presentation of the abundance and the percentage o f life forms in each community is applied. The zonal communities, belo nging to the Draba empetroides-Luzula racemosa-community-group are dom inated by tussock-grasses or giant rosette plants and seem to be confi ned to Venezuela. The most common ones are the Espeletia schultzii-Aci achne acicularis-community (up to 4150 m) and the Coespeletia moritzia na-Festuca tolucensis-community (4150-4500 m). The Festuca fragilis-Or itrophium paramense-community and the Coespeletia timotensis-community occur between 4500 and 4600 m. The azonal communities, referred to th e Gentiana sedifolia-Carex amicta-community-group and the Aciachnetum pulvinatae, are dominated by cushion grasses, rosette plants or cushio n plants and have a wide distribution along the Andes. The Aciachnetum pulvinatae is characteristic of former lakelets. The Carex bonplandii -Lache-milla sprucei-community (Marchantia-Epilobietalia) and the Wern erion-community (Wernerietalia) are characteristic vegetation types of mires, cushion bogs and meadows. Above 4600 up to the snow-level at 4 850 m discrete communities are lacking; isolated individuals of Festuc a fragilis, Poa pauciflora, Draba empetroides and Draba racemosa, amon g others, occur in protected places. The study revealed, that the dive rsity of the vegetation is related to an altitudinal gradient and the soil-humidity.