00330nam a2200133Ia 4500008004100000082001000041082001000051100001600061100001500077245005600092260001000148260002900158260000900187230118s9999||||xx |||||||||||||| ||und||  a574.5  bKOT/C  ar.lbkotpal  bdr.n.pbali 0aconcepts of ecology environmental and field biology  aDELHI  bvishal publishining  co.  c1989