Plant species diversity

Species-area relation in forest and grassland vegetation – a case study of measuring species diversity including lichens and bryophytes in the Curonian Spit National Park (Russia)



Diversity in a strict sense is richness in species, and appropriately measured as the number of species in a sample of standard size (Whittaker 1972). The species-area relation was used to find an appropriate plot size for different forest and grassland plant communities where vascular plants, bryophytes and lichens of all vegetation layers occur in a representative species number. The study was carried out in the Curonian Spit National Park (Russia) in the south-eastern Baltic region. In a nested plot design quadrates of 1, 4, 9, 16, 25, 49, 100, 225, 400, 625 and 900m² size were chosen for investigation. In pre-selected vegetation the first m² plot was randomly chosen along a 100m transect line. A relevé was made including all bryophytes, lichens and vascular plants of the ground layer vegetation and other surfaces (decaying wood, litter). Epiphytes up to 2m-trunk-height and any higher ones able to be reached without technical help were included. The Londo scale was used for species cover estimation. It was shown that in forest vegetation there is little difference between the ratio of epiphytes and plants of the ground layer vegetation between the 225, 400, 625 and 900m²-plots. The 400m² plot is recommended as appropriate standard area size for measuring species diversity of vegetation, considering species of the field layer and epiphytic vegetation in a representative way. Worldwide this plot size is commonly used for permanent plots or subplots in forest monitoring programs. – Bryophytes and lichens represent 50 to 75% of species in forest communities of the area. About 30 to 50% of the species are growing epiphytic and on other surfaces (e.g. woody debris). Also in dry grasslands about two thirds of the species are lichens and mosses and even more in raised bogs. This indicates that bryophytes and lichens are an important part of species richness of plant communities and should be included in vegetation surveys touching this topic.


species diversity, species-area relation, diversity indices, z-value



Subproject Information

Project runtime: 1999-04-01 until 2004-12-31
Scientific coordination: Dr. C. Dolnik



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