@article{fdi:010095583,
  title = {{S}argassum leachate initially inhibits then stimulates phytoplankton growth in coral reef waters},
  author = {{C}laquin, {P}. and {M}ussio, {I}. and {N}avon, {M}. and {R}usig, {A}. {M}. and {C}hatagnon, {A}melia and {D}romard, {C}.},
  editor = {},
  language = {{ENG}},
  abstract = {{M}assive {S}argassum accumulations in the {A}tlantic form the {G}reat {A}tlantic {S}argassum {B}elt, which fuels recurrent coastal inundation events that disrupt ecosystems by reducing light availability for phytoplankton and enriching nearshore waters with nutrients released during decomposition. {T}his study examined the short-term effects of decaying {S}argassum leachate on phytoplankton productivity and growth in {G}uadeloupe's coral reef ecosystems using several photosynthesis measurements based on fluorescence and 13{C}. {A} range of leachate concentrations were applied, under controlled conditions, to a natural phytoplankton community. {T}he study revealed two major effects of {S}argassum leachate on phytoplankton. {F}irst, leachate at concentrations >= 1 % initially inhibited photosynthesis and growth up to {D}ay 2, likely due to allelopathic substances such as polyphenols. {T}his was evidenced by near-zero {F}v/{F}m values and disrupted electron transport in {PSII}. {B}y {D}ay 3, these inhibitory effects diminished, suggesting degradation of labile inhibitory compounds or community modification. {S}econd, from {D}ay 3 onward, leachate addition stimulated phytoplankton growth, as seen in increased biomass, primary production ({JVII}max), and carbon fixation. {T}his nutrient-driven response was accompanied by reduced {C}/{C}hl a ratios and improved photosynthetic efficiency (lower & {F}cy;e,{C} values), indicating alleviation of nutrient limitations, particularly nitrogen and phosphorus. {T}hese findings underscore the dual role of {S}argassum leachate: an initial suppressive impact through allelopathy and a subsequent nutrient enrichment effect driving phytoplankton blooms. {S}uch dynamics highlight the significant and complex influence of {S}argassum strandings, combining ecological stress with nutrient-driven productivity changes.},
  keywords = {{P}hytoplankton ; {S}argassum leachate ; {P}hotosynthesis ; {A}llelopathy ; {C}ontrolled conditions ; {GUADELOUPE} ; {ATLANTIQUE}},
  booktitle = {},
  journal = {{J}ournal of {E}xperimental {M}arine {B}iology and {E}cology},
  volume = {593},
  numero = {},
  pages = {152146 [11 ]},
  ISSN = {0022-0981},
  year = {2025},
  DOI = {10.1016/j.jembe.2025.152146},
  URL = {https://www.documentation.ird.fr/hor/fdi:010095583},
}