title: Benthic primary production budget of a Caribbean reef lagoon (Puerto Morelos, Mexico).
abstract: High photosynthetic benthic primary production (P) represents a key ecosystem service provided by tropical coral reef systems. However, benthic P budgets of specific ecosystem compartments such as macrophyte-dominated reef lagoons are still scarce. To address this, we quantified individual and lagoon-wide net (Pn) and gross (Pg) primary production by all dominant functional groups of benthic primary producers in a typical macrophyte-dominated Caribbean reef lagoon near Puerto Morelos (Mexico) via measurement of O₂ fluxes in incubation experiments. The photosynthetically active 3D lagoon surface area was quantified using conversion factors to allow extrapolation to lagoon-wide P budgets. Findings revealed that lagoon 2D benthic cover was primarily composed of sand-associated microphytobenthos (40%), seagrasses (29%) and macroalgae (27%), while seagrasses dominated the lagoon 3D surface area (84%). Individual Pg was highest for macroalgae and scleractinian corals (87 and 86 mmol O₂ m(-2) specimen area d(-1), respectively), however seagrasses contributed highest (59%) to the lagoon-wide Pg. Macroalgae exhibited highest individual Pn rates, but seagrasses generated the largest fraction (51%) of lagoon-wide Pn. Individual R was highest for scleractinian corals and macroalgae, whereas seagrasses again provided the major lagoon-wide share (68%). These findings characterise the investigated lagoon as a net autotrophic coral reef ecosystem compartment revealing similar P compared to other macrophyte-dominated coastal environments such as seagrass meadows and macroalgae beds. Further, high lagoon-wide P (Pg: 488 and Pn: 181 mmol O₂ m(-2) lagoon area d(-1)) and overall Pg:R (1.6) indicate substantial benthic excess production within the Puerto Morelos reef lagoon and suggest the export of newly synthesised organic matter to surrounding ecosystems.
authors.affiliation: Coral Reef Ecology Group (CORE), Leibniz Center for Tropical Marine Ecology (ZMT), Bremen, Germany.
authors.forename: Malik S
authors.initials: MS
authors.lastname: Naumann
authors.affiliation: Coral Reef Ecology Group (CORE), Leibniz Center for Tropical Marine Ecology (ZMT), Bremen, Germany.
authors.forename: Carin
authors.initials: C
authors.lastname: Jantzen
authors.affiliation: Coral Reef Ecology Group (CORE), Leibniz Center for Tropical Marine Ecology (ZMT), Bremen, Germany.
authors.forename: Andreas F
authors.initials: AF
authors.lastname: Haas
authors.affiliation: Unidad Academica Puerto Morelos, Instituto de Ciencias del Mar y Limnologıa, Universidad Nacional Autonoma de Mexico (UNAM), Cancun, Quintana Roo, Mexico.
authors.forename: Roberto
authors.initials: R
authors.lastname: Iglesias-Prieto
authors.affiliation: Coral Reef Ecology Group (CORE), Leibniz Center for Tropical Marine Ecology (ZMT), Bremen, Germany ; Faculty of Biology and Chemistry, University of Bremen, Bremen, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Wild
mesh_terms: D000818:Animals; D037421:Anthozoa; D057894:Coral Reefs; D017753:Ecosystem; D008800:Mexico; D012624:Seaweed