RIQUEZA ESPECÍFICA EM ÁREAS DE CAMPO NATIVO IMPACTADAS POR VISITAÇÃO TURÍSTICA E PASTEJO NO PARQUE NACIONAL DOS CAMPOS GERAIS, PR

The species diversity in native grassland areas tha t are under impact of tourism and grazing at Campos Gerais National Park, Parana, Brazil. Campos Gerais National Park (PNCG) has areas of grassland under high anthropogenic pressure, as expansion of agricu ltural activities, livestock, forestry and disorder ly tourism. Due to these impacts, there is a tendency to decrease local biodiversity by selection of more resistant species. This paper focuses the grassland community answers to mowing, grazing and tourism. In four sampling sites it was determined 107 taxa belo nging to 23 botanic families. The main families are Asteraceae (24 taxa), Poaceae (24 taxa) and Fabaceae (14 taxa). Species diversity varied from 27 to 75 species. In relation to species number, non-grazed areas presented greater diversity than other ones; it points to that touristic visitation may cause lower impact than grazing or mowing. In spite of the anthropoge nic factors, the focused sites presented high specific diversity in relation to related areas. In relation to species diversity, grazing or mowing are equal. Six genera presented potentiality as bioindicators of preserve d environments: Croton , Galactia , Periandra , Cuphea , Pavonia, and Commelina , although more sample areas are necessary to reliable results.