Diversity And Biogeography Of Bryophytes In Haitan Island And Its Adjacent Islands,Fujian Province

Haitan island is located in the south-east coast of China,it is the largest island in Fujian Province and the main island in Pingtan County?25°15'-25°45'N,119°32'-120°10'E?.To understand the bryophyte diversity and biogeographic characteristics of Haitan Island and its surrounding islands,Dongxiang Island,Dalian Island,Xiaolian Island,Caoyu Island,Chengyu Island,Tangyu Island,Beigong Island,Nangong Island,Dongjia Island,Longmu Island,Gaoyu Island,Xianjiao Island,Qianqi Island,Nanheng Island,Tangyu Island,Wangmayu Island,Jingyu Island and Xiaojia Island,bryophyte ecological survey,specimen collection and identification,data analysis were carried out.The main research results were as follows:1.Through the identification of 1960 bryophyte specimens,there were 39families,68 genera,161 species and 7 varieties.Among them,11 families,140 genera and 20 species belonged to liveworts and 26 families,51 genera,138 species and 7varieties were mosses and only 3 families,3 generas and 3 species of hornworts.2.Pottiaceae,Hypnaceae,Brachytheciaceae,and Bryaceae were the common families,Brachythecium,Bryum,Hypnum,Barbula,Dicranella,Fissidens,Physcomitrium and Taxiphyllum were the common genera.3.The ecological distribution types of bryophytes in this area were on soil,stone,cement,soil on stone,tree or other substrates.Most of specimens were collected from soil,accounting for 43.47%of all specimens.Stone and soil on stone were the second,accounting for 23.47%and 20.31%respectively.Specimens of Pottiaceae,Hypnaceae,Brachytheciaceae and Bryaceaewere were the common species of soil,stone and soil on stone surface.4.The floristic element of bryophytes in the region were complex,mainly in the North Temperate?27.38%?and E.Asia?21.43%?,East Asia-North America?10.71%?and Pantropic?8.93%?distribution were the second.This result was similar to the result of Zhoushan Islands and Shengsi Archipelago.5.The area?A?,altitude?E?and coastline?C?of the islands played important roles in the distribution of bryophytes;their relationships could be described by these following functions:S=2.6900*A^3.0488?r=0.9365?,S=6.1131*E^8.9680?r=0.9634?,S=1.4130*C^4.4578?r=0.9238?.6.To explore the salt stress adaptability of bryophyte,Codriophorus aciculare?Hedw.?P.Beauv.,Hypnum cupressiforme var.lacunosum.,Campylopus subfragilis Renauld&Cardot.,Philonotis thwaitesii Mitt.,Brachythecium formosanum Takai.,and Haplocladium microphyllum?Hedw.?Broth.were selected for the experiments.The results showed that the fv/fm of the six bryophytes was not significantly different under different salt treatment concentrations?0.3 ppt?0.6 ppt?0.9 ppt?of the same bryophytes and different bryophytes under the same salt concentration?0.3 ppt?0.6ppt?0.9 ppt?,but the value showed a downward trend with the prolongation of culture time.The UV spectra of bryophytes treated with different concentrations of salt were compared.At three salinity levels,the UV absorption curves of Brachythecium formosanum Takai.and Hypnum cupressiforme var.lacunosum.showed an increasing trend,and the UV absorption curves of both Codriophorus aciculare?Hedw.?P.Beauv.and Campylopus subfragilis Renauld&Cardot.showed a tendency to rise first and then decrease at three salinity levels.The UV absorption curves of Haplocladium microphyllum?Hedw.?Broth.and Philonotis thwaitesii Mitt.at three salinities showed a tendency of first rising and then decreasing.The results showed that bryophytes were affected by salt stress during 36 days.