The spatial variability of mesozooplankton(MZ)community characteristics,with an emphasis on the predominant taxa,copepods,were evaluated between two distinct coastal water environments of Mangalore:the Netravati-Gurup...The spatial variability of mesozooplankton(MZ)community characteristics,with an emphasis on the predominant taxa,copepods,were evaluated between two distinct coastal water environments of Mangalore:the Netravati-Gurupura estuarine system(NGES)and the adjacent nearshore waters(<20 m depth)on the southwest coast of India during winter 2018.The nearshore waters were characterised by uniformly distributed hydrographic properties,particularly in terms of water column temperature,salinity and turbidity.This well-mixed water column likely stimulated increased phytoplankton chlorophyll a concentrations[av.(2.9±2.2)mg/m^(3)],which in turn supported higher MZ biomass[av.(0.4±0.15)mL/m^(3)]and abundance[av.(6889±3387)ind./m^(3)]in the nearshore waters.In contrast,the NGES exhibited highly variable hydrographic conditions,leading to inconsistent chlorophyll a[av.(3.2±3.7)mg/m^(3)],along with significantly lower MZ biomass[av.(0.1±0.2)mL/m^(3)]and abundance[av.(238±339)ind./m^(3)].The MZ community was dominated by herbivorous copepods(HCs),particularly Bestiolina similis,in the entire study region;however,the nearshore waters supported a more diverse taxon.The overall dominance of HCs,e.g.,B.similis and Pseudodiaptomous aurivillii,in the nearshore waters,indicates the presence of stable hydrographic conditions,especially consistently higher salinity and chlorophyll a level.In contrast,the unstable hydrographic conditions in the NGES,primarily reflected in the uneven salinity distributions,likely contributed to the reduced MZ biomass and abundance.The relative increase in the abundance of B.similis observed exclusively in the euhaline zones of the estuary highlights the significant influence of neritic waters.展开更多
基金the Port and Fisheries Division of the PWD and IWT Department, Government of Karnataka,for providing the research grant for executing the project(SSP 3243)
文摘The spatial variability of mesozooplankton(MZ)community characteristics,with an emphasis on the predominant taxa,copepods,were evaluated between two distinct coastal water environments of Mangalore:the Netravati-Gurupura estuarine system(NGES)and the adjacent nearshore waters(<20 m depth)on the southwest coast of India during winter 2018.The nearshore waters were characterised by uniformly distributed hydrographic properties,particularly in terms of water column temperature,salinity and turbidity.This well-mixed water column likely stimulated increased phytoplankton chlorophyll a concentrations[av.(2.9±2.2)mg/m^(3)],which in turn supported higher MZ biomass[av.(0.4±0.15)mL/m^(3)]and abundance[av.(6889±3387)ind./m^(3)]in the nearshore waters.In contrast,the NGES exhibited highly variable hydrographic conditions,leading to inconsistent chlorophyll a[av.(3.2±3.7)mg/m^(3)],along with significantly lower MZ biomass[av.(0.1±0.2)mL/m^(3)]and abundance[av.(238±339)ind./m^(3)].The MZ community was dominated by herbivorous copepods(HCs),particularly Bestiolina similis,in the entire study region;however,the nearshore waters supported a more diverse taxon.The overall dominance of HCs,e.g.,B.similis and Pseudodiaptomous aurivillii,in the nearshore waters,indicates the presence of stable hydrographic conditions,especially consistently higher salinity and chlorophyll a level.In contrast,the unstable hydrographic conditions in the NGES,primarily reflected in the uneven salinity distributions,likely contributed to the reduced MZ biomass and abundance.The relative increase in the abundance of B.similis observed exclusively in the euhaline zones of the estuary highlights the significant influence of neritic waters.
