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Due to decades of loss of grassland diversity across Europe, there is a need to identify factors affecting species composition and diversity in managed meadows. The aim of the current study was to assess how ecological, landscape and management factors may affect plant species composition, biodiversity and forage value in Alpine hay meadows. Species composition, Shannon index and forage value were obtained from phytosociological relevés. Twenty explanatory variables were selected from a set of ecological, landscape and management factors. Their effects on plant species composition, Shannon index and forage value were analysed by applying the variation partitioning approach. Plant species composition was related to sixteen factors, explaining 35·6% of the variability. Shannon index and forage value were related to eleven factors, explaining 47·8 and 40·8% of their total variation respectively. Ecological factors were the main set explaining species composition and diversity, whereas none of the three individual groups of factors (ecological, landscape, management) significantly explained variability within forage value. Overall, the effects of the three groups of factors accounted for 70% of the total variability in plant species composition, but less than half that of Shannon index and of forage value. [ABSTRACT FROM AUTHOR]

Themeda triandra Forssk. is one of the most widespread grasses in the dry to mesic prairie ecosystems of Africa, Asia and Australia. It is of particular interest due to its high value as a forage species for wildlife and livestock, and its potential use in landscaping practices. In this review we have collated information from the many studies that have been devoted to this species since the 1960s to provide information about the species' distribution, taxonomy, morphology, ploidy and reproduction, and to describe its vegetation and germination and their relationship with the most important ecological aspects of its preferred habitats. Agronomic aspects are considered in detail, with particular focus on the role of T. triandra as a forage species and the relative importance of grazing, fire and rainfall regimes for its management. We also explore how this species can help with the rehabilitation of degraded areas, soil and water conservation, countering exotic species invasion and landscaping in general. We conclude with a brief discussion of the as yet unresolved taxonomic relationship between the African species T. triandra and the Australian species Themeda australis. [ABSTRACT FROM AUTHOR]