Costa, H.H.2010-07-062010-07-061986https://dl.nsf.gov.lk/handle/1/5294Sri LankaFreshwater ChemistryFreshwater Aquatic FaunaFreshwater fishFish ProductionExotic Aquatic WeedsSalviniaAquatic WeedsFreshwater PollutionSewageEutrophicationWeedicidesInsecticidesIndustrial WastesDeforestationSiltsAquatic ResourcesEducationFreshwater as a natural resource in sri Lanka