production. Bu ffe rs of nat ive vegerar ion which receive lower levels of P could be harvested for wood (ie fence posts, firewood , ere) or wi ldflowers. In rhe long term , harvesting of buffe r strips and rhe recycling of P back ro fa rmlands are essential, otherwise buffers wil l become a reservoir and source of nutrients as signi fica nt as ag ricu ltural soils, ul tim ately reaching an equil ibrium scare whereby rbey lose as much P as rhey captu re.
Acknowledgments The authors acknowledge rhe assisrance of South Coast Estuaries Project Group, in particular Ashley Proue, Tony Cremin (who prepared Figure 1) and Peter Hocki ng, and the Water Au thori ty of Western Australia in rhe collecrion of info rmation assoc iated wirh rhis article. Thanks also ro Ross George and Don Mcfarlane for their helpful comments on rhe manuscript.
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Authors David Weaver is a l?esearch Olfiter with the \Vestern Australian Department of Agrimlt11re. He is mrrently investigating the mechanis111s for nutrient loss from farmla11d to Oyster Harbour and I/Sing these to contribl/te to the establishment of Sl/stainable agrimlt1tral systems. Dr Luke Pen is an Environmental Officer with the Albany \'Vaterways Management Authority. His main area of expertise is riverine ecology and he recently completed a survey of the condition of the riparian vegetation alo11g the Ka/gem Rive1'. The results of the sl/rvey are being med to promote better management of the river system. Adrian Reed is a Technical Officer with the Western Australian Department of Agrimlture. He provides technical s11pport in the areas of hydrology and water chemistry for the department's smtainable agrimltttral systems program in the Oyster Harbour catchme~t
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