According to WWF , an ecoregion is defined as a `` relatively large unit of land or water containing a characteristic set of natural communities that share a large majority of their species , dynamics , and environmental conditions ( Olson & Dinerstein 1998 , 2002 ; TNC 1997 ) . ''
According to the WWF , an ecoregion is defined as a `` relatively large unit of land or water containing a characteristic set of natural communities that share a large majority of their species , dynamics , and environmental conditions ( Dinerstein et al. 1995 , TNC 1997 ) . ''