title: Impact of pond aquaculture effluents on seagrass performance in NE Hainan, tropical China.
abstract: The impact of pond aquaculture effluents on the distribution and performance of seagrasses was examined in NE Hainan, tropical China. Samples were taken along transects in three back-reef areas with different extent of aquaculture production in their hinterland. High δ(15)N in seagrass leaves and epiphytes (6-9‰) similar to values in pond effluents documented aquaculture as dominant nitrogen source in the back-reefs with decreasing impact with distance from shore. Seagrass species abundance, shoot density and biomass were lower and concentrations of nutrients, chlorophyll and suspended matter were higher at nearshore sites with high and moderate pond abundance than at the control site. High epiphyte loads and low δ(34)S in seagrass leaves suggest temporal shading and sulphide poisoning of the nearshore seagrasses. Observed gradients in environmental parameters and seagrass performance indicate that the distance from the pond outlets and size of the adjacent pond agglomeration are major determinants of seagrass degradation.
authors: Leibniz Center for Tropical Marine Ecology (ZMT) GmbH, Fahrenheitstr. 6, 28359 Bremen, Germany. Electronic address: lucia.herbeck@zmt-bremen.de.
authors: Lucia S
authors: LS
authors: Herbeck
authors: Leibniz Center for Tropical Marine Ecology (ZMT) GmbH, Fahrenheitstr. 6, 28359 Bremen, Germany; Center for Marine Environmental Sciences (MARUM), University of Bremen, 28359 Bremen, Germany.
authors: Miriam
authors: M
authors: Sollich
authors: Leibniz Center for Tropical Marine Ecology (ZMT) GmbH, Fahrenheitstr. 6, 28359 Bremen, Germany.
authors: Daniela
authors: D
authors: Unger
authors: Department of Biology, University of Southern Denmark, 5230 Odense M, Denmark.
authors: Marianne
authors: M
authors: Holmer
authors: Leibniz Center for Tropical Marine Ecology (ZMT) GmbH, Fahrenheitstr. 6, 28359 Bremen, Germany.
authors: Tim C
authors: TC
authors: Jennerjahn
mesh_terms: D017756:Aquaculture / Q000379:methods*; D044822:Biodiversity; D018533:Biomass; D002681:China; D002734:Chlorophyll / Q000737:chemistry*; D004784:Environmental Monitoring / Q000379:methods; D005843:Geography; D019015:Geologic Sediments / Q000737:chemistry; D031321:Hydrocharitaceae / Q000502:physiology*; D009584:Nitrogen / Q000737:chemistry*; D018515:Plant Leaves / Q000737:chemistry*; D061005:Ponds; D013053:Spectrophotometry; D013440:Sulfides / Q000737:chemistry; D014867:Water / Q000737:chemistry; D014873:Water Pollutants
chemical_list: D013440:Sulfides; D014873:Water Pollutants; D014867:Water; D002734:Chlorophyll; D009584:Nitrogen
keywords: Biodiversity; Epiphytes; Eutrophication; Mixed seagrass meadows; Nitrogen and sulphur stable isotopes; Pond aquaculture