Changes of macro-benthic faunal community with stand age of rehabilitated Kandelia candel mangrove in Jiulongjiang Estuary,China

摘要

Distribution properties of macro-benthic faunal communities were compared among rehabilitated Kandelia candel forests of different ages in Jiulongjiang Estuary,China.From July 2005 to April 2006,seasonal surveys were conducted within four representative forests-K4,K7,K19 and K43,with ages of 4,7,19 and 43 years,respectively.Two non-vegetated flats(NF1 and NF2)were set as the references.Numbers of faunal species in rehabilitated forests were higher than NF1 and NF2,while younger forests(K4 and K7)generally had more macro-benthic fauna species than older ones(K19 and K43).Among the total 24 species recorded,Uca arcuata,Metaplax elegans,Phascolosoma esculenta and Littoraria melanostoma were dominant.Macro-benthic faunal community structures were different among the four rehabilitated K.candel forests.The dominant species in younger forests was M.elegans,while U.arcuata had a higher abundance than M.elegans in non-vegetation flats and older forests.Gastropods were abundant in younger forests.Distribution properties of dominant species differed among rehabilitated K.candel forests.U.arcuata had the largest density in non-vegetated flats,and was infrequent in younger forests.M.elegans had high abundances in younger forests.High abundance of P.esculenta was found in older forests,while L.melanostoma was more abundant in younger forests.Since both macro-benthic faunal community and vegetation were similar in K19 and K43,rehabilitated K.candel mangrove was considered steady 19 years after being planted.That is,in the case of macro-benthic fauna and vegetation,a K.candel mangrove may evolve to a mature state at a stand age of about 20 years.