A Study of Vegetation is an Important Indication data for the Distribution or Communities and their Relation with Corporeal Environment of Certain Area

摘要

Pteridophytes  are  the  primitive  vascular  plants,  they  are  found  scattered  all  over  the  globe  and quite many of them occur in India. However, they are not found throught the country. Pteridophytes make as important contribution to the earth’s plant diversity. Being the second largest group of vascular plants, they form  a  significant  and  dominant  component  of  many  plant  communities.  All  human  activities  disturb  the vegetation  by  eliminating  many  species.  So  an  up  to  date  study  is  very important  for  knowing  about  flora, especially  in  the  case  of  pteridophytes. The  present  effort  was  undertaken  to  enumerate  the  pteridophytic species  present  in  Kilavarai    river  situated  in  Palni  hills  of southern  Western  Ghats,  Tamil  Nadu, India,  the  study  was  carried  out  from  December  2014  to  January  2016.  The  result  ofthe  present  study revealed  that  36  pteridophytic  species  belonging  to  25  genera  distributed  among  19  families  were  noted from  the  study  site.  Among  the  families  recorded,  Adiantaceae  (16.67%)  was  found  to  be  dominant  and largest  family  comprising  6  species.  Polypodiaceae  and  Pteridaceae  (each  of  11.11%)  shared  the  second largest  family  status;  they  were  represented  by  4  species  each.  The  third  largest  family  was  Lycopodiaceae (8.33%);    it    was    represented    by    3    species.    The    families    Cheilanthaceae,        and Selaginellaceae  were  recorded  with  each  of  2  species  (5.56%)  and  11  families  were  represented  by  single species  (2.78%).  Moreover, terrestrial  species  (27  species)  were  found  to  be  more  in  number  than  epiphytic (5  species),  3  species    were  foundas  both  epiphytic  and  lithophytic  species  and  1  species  was  recorded  as purely lithophytic.