@article{fdi:010091792,
  title = {{C}arbon and nitrogen sources in tropical coastal lagoon food webs under variable hydrological conditions},
  author = {{A}ndrisoa, {A}ladin and {S}tieglitz, {T}homas and {M}asimana, {M}. and {S}ambo, {B}. and {R}aimbault, {B}. and {M}ahafina, {J}.},
  editor = {},
  language = {{ENG}},
  abstract = {{W}hilst the impact of continental and marine nutrient sources on the ecological functioning of coastal food webs is well investigated in temperate regions, tropical ecosystems remain less well understood, in particular coastal lagoons. {I}n this study, the sources of carbon and nitrogen in a coastal lagoon system in the southeast of {M}adagascar are traced using stable isotopes of carbon (delta 13{C}) and nitrogen (delta 15{N}). {T}hree interconnected coastal lagoons with different degree of river influence and eutrophication are investigated. {T}heir food webs are assessed with respect to spatial and seasonal (wet and dry seasons) variations in lagoon water conditions, as well as with respect to the sources of nutrients and organic matters. {R}esults show that river input is the main source of {NO}3-, and that {NO}3- supply is significantly higher during the wet season. {I}n contrast, {NH}4+ is produced internally in the lagoon, and concentrations are higher during the dry season. {A} lower delta13{C} value observed in particulate organic matter ({POM}; proxy of phytoplankton) indicates terrestrial-riverine carbon inputs, which generally have low delta 13{C} values. {D}uring the dry season, exceptionally high delta 15{N} values of lagoon {POM} suggest the uptake of newly produced lagoon water {NH}4+ and / or the 15{N} enrichment of lagoon {POM} pool due to mineralization, resulting in 15{N} enrichment in consumers. {M}oreover, delta 13{C} and delta 15{N} values of consumers (fishes and invertebrates) reflect predominantly those of lagoon {POM} and sediment organic matter ({SOM}), suggesting that consumers primarily depend on lagoon {POM} and {SOM} as sources of carbon and nitrogen. {T}he delta 15{N} values in consumers further indicate that some species feed on more than one trophic level, suggesting flexible foraging strategy of consumers as a function of food source availability. {T}his study demonstrates the roles of both river inflow and sediment in supplying carbon and nitrogen to a coastal lagoon food web, documenting the ecological implications of seasonal variations in lagoon hydrological conditions.},
  keywords = {{MADAGASCAR}},
  booktitle = {},
  journal = {{E}stuarine, {C}oastal and {S}helf {S}cience},
  volume = {309},
  numero = {},
  pages = {108975 [12 ]},
  ISSN = {1096-0015},
  year = {2024},
  DOI = {10.1016/j.ecss.2024.108975},
  URL = {https://www.documentation.ird.fr/hor/fdi:010091792},
}