title: Temporal coherence among tropical coastal lagoons: a search for patterns and mechanisms.
abstract: Temporal coherence (i.e., the degree of synchronicity of a given variable among ecological units within a predefined space) has been shown for several limnological features among temperate lakes, allowing predictions about the structure and function of ecosystems. However, there is little evidence of temporal coherence among tropical aquatic systems, where the climatic variability among seasons is less pronounced. Here, we used data from long-term monitoring of physical, chemical and biological variables to test the degree of temporal coherence among 18 tropical coastal lagoons. The water temperature and chlorophyll-a concentration had the highest and lowest temporal coherence among the lagoons, respectively, whereas the salinity and water colour had intermediate temporal coherence. The regional climactic factors were the main factors responsible for the coherence patterns in the water temperature and water colour, whereas the landscape position and morphometric characteristics explained much of the variation of the salinity and water colour among the lagoons. These results indicate that both local (lagoon morphometry) and regional (precipitation, air temperature) factors regulate the physical and chemical conditions of coastal lagoons by adjusting the terrestrial and marine subsidies at a landscape-scale. On the other hand, the chlorophyll-a concentration appears to be primarily regulated by specific local conditions resulting in a weak temporal coherence among the ecosystems. We concluded that temporal coherence in tropical ecosystems is possible, at least for some environmental features, and should be evaluated for other tropical ecosystems. Our results also reinforce that aquatic ecosystems should be studied more broadly to accomplish a full understanding of their structure and function.
authors.affiliation: Departamento de Ecologia, Instituto de Biologia, Prédio do CCS, Universidade Federal do Rio de Janeiro – UFRJ, Ilha do Fundão, CP 68020, CEP 21941-590, Rio de Janeiro, RJ, Brazil.
authors.forename: A
authors.initials: A
authors.lastname: Caliman
authors.forename: L S
authors.initials: LS
authors.lastname: Carneiro
authors.forename: J M
authors.initials: JM
authors.lastname: Santangelo
authors.forename: R D
authors.initials: RD
authors.lastname: Guariento
authors.forename: A P F
authors.initials: AP
authors.lastname: Pires
authors.forename: A L
authors.initials: AL
authors.lastname: Suhett
authors.forename: L B
authors.initials: LB
authors.lastname: Quesado
authors.forename: V
authors.initials: V
authors.lastname: Scofield
authors.forename: E S
authors.initials: ES
authors.lastname: Fonte
authors.forename: P M
authors.initials: PM
authors.lastname: Lopes
authors.forename: L F
authors.initials: LF
authors.lastname: Sanches
authors.forename: F D
authors.initials: FD
authors.lastname: Azevedo
authors.forename: C C
authors.initials: CC
authors.lastname: Marinho
authors.forename: R L
authors.initials: RL
authors.lastname: Bozelli
authors.forename: F A
authors.initials: FA
authors.lastname: Esteves
authors.forename: V F
authors.initials: VF
authors.lastname: Farjalla
mesh_terms: D002734:Chlorophyll / Q000032:analysis*; D000077194:Chlorophyll A; D004784:Environmental Monitoring / Q000379:methods*; D054712:Salinity; D012621:Seasons; D012623:Seawater / Q000032:analysis*; D014329:Tropical Climate
chemical_list: D002734:Chlorophyll; D000077194:Chlorophyll A