Fish farming enhances biomass and nutrient loss in Posidonia oceanica (L.) Delile
- 1 February 2009
- journal article
- Published by Elsevier BV in Estuarine, Coastal and Shelf Science
- Vol. 81 (3), 390-400
- https://doi.org/10.1016/j.ecss.2008.11.014
Abstract
Fish farming impact on the seasonal biomass, carbon and nutrient (nitrogen and phosphorus) balance of the endemic Mediterranean seagrass Posidonia oceanica was assessed in the Aegean Sea (Greece) in order to detect changes in magnitude and fate of seagrass production and nutrient incorporation with organic loading of the meadows. Phosphorus concentration in the leaves, rhizomes and roots was enhanced under the cages throughout the study. Standing biomass was diminished by 64% and carbon, nitrogen and phosphorus standing stock by 64%, 61% and 48%, respectively, under the cages in relation to those at the control. Seagrass production decreased by 68% and element (C, N, P) incorporation by 67%, 58% and 58%, respectively, under the cages. Leaf shedding was reduced by 81% and loss of elements (C, N, and P) through shedding by 82%, 74% and 72%, respectively, under the cages. Leaf and element (C, N, P) residual loss rate, accounting for grazing and mechanical breakage of leaves, was decreased by 79%, 85%, 100% and 96%, respectively, at the control station. At the control station, 13.98 g C m−2 yr−1, 1.91 g N m−2 yr−1 and 0.05 g P m−2 yr−1 were produced in excess of export and loss. In contrast, under the cages 12.69 g C m−2 yr−1, 0.31 g N m−2 yr−1 and 0.04 g P m−2 yr−1 were released from the meadow. Organic loading due to fish farm discharges transformed the seagrass meadow under the cages from a typical sink to a source of organic carbon and nutrients.Keywords
This publication has 47 references indexed in Scilit:
- Effects of fish farm waste on Posidonia oceanica meadows: Synthesis and provision of monitoring and management toolsMarine Pollution Bulletin, 2008
- Stimulation of sulfate reduction rates in Mediterranean fish farm sediments inhabited by the seagrass Posidonia oceanicaBiogeochemistry, 2007
- Sedimentation of organic matter from fish farms in oligotrophic Mediterranean assessed through bulk and stable isotope (δ13C and δ15N) analysesAquaculture, 2006
- Effects of organic matter input from a fish farming facility on a Posidonia oceanica meadowEstuarine, Coastal and Shelf Science, 2003
- Variability in Detritus Stocks in Beds of the Seagrass Cymodocea nodosaBotanica Marina, 2001
- Fate of production of the seagrass Cymodocea nodosa in different stages of meadow formationMarine Ecology Progress Series, 2000
- Effects of fish farming on seagrass (Posidonia oceanica) in a Mediterranean bay: seagrass decline after organic loading cessationOceanologica Acta, 1999
- Preliminary data on the impact of fish farming facilities on Posidonia oceanica meadows in the MediterraneanOceanologica Acta, 1999
- Reconstruction of seagrass dynamics: age determinations and associated tools for the seagrass ecologistMarine Ecology Progress Series, 1994
- Determination of soluble phosphate, and total phosphorus in sea-water and of total phosphorus in marine mudsMicrochimica Acta, 1956