Influence of two non-indigenous plants on intertidal macrobenthic communities in Ximen Island Special Marine Protected Area, China

Abstract

Many coastal habitats are being substantially altered by non-indigenous plants (NIP). In the present study, intertidal macrobenthic communities of three habitats – a non-vegetated tidal flat (TF), a marsh with the smooth cordgrass Spartina alterniflora (SA) and a Kandelia candel mangrove forest (KC) – were examined during periods of ebb tide in February, May, August and November 2015 in Ximen Island Special Marine Protected Area, Zhejiang Province, China. S. alterniflora was introduced from North America in 1979 and invaded Ximen Island spontaneously. K. candel was a direct, artificial introduction in 1957 from Fujian, China. A total of 48 species of macrobenthos were collected from Ximen Island. The average density of macrobenthos in TF, SA and KC was 1365, 1398 and 669 ind./m2, respectively, and the average biomass of macrobenthos in TF, SA and KC was 144.13, 43.00 and 138.70 g/m2, respectively. There were no significant differences among the three habitats on density and biomass of macrobenthos, with the exception of density in spring and biomass in autumn. Diversity indices of macrobenthos did not exhibit significant differences among the three habitats, except for Margalef’s richness index (d) in KC. However, Results of one-way analysis of similarity (ANOSIM) revealed significant differences in macrobenthic community structure among the three habitats and four seasons. It was concluded that, although few significant differences were observed in the density, biomass and diversity indices of macrobenthos among habitats, there were significant changes in the macrobenthic communities’ structure after the introduction of S. alterniflora and K. candel. Therefore, when we use plants as ecological engineering materials, we need to take into account all of their potential ecological consequences.