Ecological niche and differentiation of major nekton species in the spring and autumn of Wenzhou Oujiang Estuary
Based on data collected from two fisheries resource surveys in the vicinity of the Oujiang River Estuary in Wenzhou in the autumn of 2020(November)and the spring of 2021(March),the ecological niche and differentiation of major nekton species were analyzed using methods such as the index of relative importance(IRI),ecological niche width(Bi),ecological niche overlap(Oik),and redundancy analysis(RDA).The species richness of nekton species in the Wenzhou Oujiang River estuary was high with a higher number of dominant species in the spring than in the autumn.The index of relative importance of Oratosquilla oratoria was the highest in autumn.The niche width(Bi)of the major nekton species in the two seasons ranged from 1.20 to 7.53.The broad niche width species(Bi≥6)included the Charybdis japonicain both seasons,Collichthys lucidus and Portunus trituberculatus in autumn and Palaemon carinicaudain spring.Medium niche width species(3<Bi<6)included Harpadon nehereus,Oratosquilla oratoriain autumn and Lateolabrax japonicusin spring,etc.Narrow niche width species(0<Bi≤3)included Coilia nasusin autumn and Oratosquilla oratoriain spring,etc.The niche overlap in the two seasons ranged from 0.03 to 0.96,with significant differences in the overlap between species pairs,which were mainly influenced by differences in feeding habits,habitat and predation relationships.RDA mainly reflected the ecological niche differentiation from two perspectives:the impact of environmental factors on species distribution and the explanation of unreasonable ecological niche overlap between species pairs.
NETL
NSTL
万方数据
