On Geographical Distribution Patterns And Potential Region Prediction Of Partial Moss Taxa In China

Bryophyte is an important community in the plant kingdom. With the longresearch history of the diversity and regionalization of bryophytes in China, thereaccumulate a great number of literatures about the floristic geographical distribution ofbryophytes. But people still not clear about the distribution frequencies of variousfamilies, genera and species in different areas of China without the quantitativecomparison of the distribution patterns of bryophytes and the systematic comparison ofregional differentiation of floristic composition of bryophytes in China. Moreover,with the accumulation of climate data and application of species distribution predictionmodel, human beings can take advantage of the existing species distribution data topredict the potential distribution range of organisms under the current climateconditions and the conditions of climate warming. But these methods cannot beapplied to study the geographical distribution of bryophytes.This paper systematically collects floristic data of bryophyte research of116areasin China since1983. Based on these data, it statistically analyses the flora ofbryophytes of these areas and takes the Macromitrium sinense Bart as example topredict the modern distribution range of this species and its climatic adaptationcharacteristics at28important nature reserves. Randomly selecting41genera ofvarious climatic adaptation and geographical distribution characteristics in these116areas, it predicts their distribution range will changes under the conditions of climatewarming in2070. The main results are as follows:1. There is a record of2239species,416genera, and64families in these116areas. Among these areas, the richest flora are in Yellow Mountain, Anhui Province; Leigong Mountain, Guizhou Province; Dujiang Dam, Sichuan Province; Fuoping,Shanxi Province; Changbai Mountain, Jilin Province; Emei Mountain, SichuanProvince; Dawei Mountain, Yunnan Province; and Qilian Mountain, Gansu Province.The records of the species in these areas are respectively420,377,358,377,358,333,321and300.2. The most widely distributed species in China are Funaria hygrometrica, Bryumargenteum, Thuidium cymbifolium, Entodon compressus, Weissia controversa,Taxiphyllum taxirameum (Mitt.), Herpetineuron toccoae, Haplocladium angustifolium,Haplocladium microphyllum, Hyophila involuta and Plagiomnium cuspidatum (Hedw)with the distribution frequencies of50%-63.33%in the116areas. For2239species ofbryophyte, the relationship between the distribution frequency (X) and the number ofspecies (Y) is Y=630.37784*e-35.165483*X,(r=0.9993, P<0.001) which means thenumber of species declines exponentially with the increase of distribution frequency.In the416genera of bryophyte in116areas, the most widely distributed is Bryum withthe distribution in the97.44%of these116areas, followed by Entodon, Fissidens,Plagiomnium, Thuidium with the distribution frequencies of90.60-81.20%. Therelationship of distribution frequency (X) and the number of genera (Y) is Y=58.52*e-0.2222*X,(r=0.9271, P<0.001). With the increase of distribution frequency, thenumber of genera falls exponentially. Compared with the angiosperms, characteristiccomposition proportion in bryophytes may be generally low. According to thestatistical results, it is found that almost half of2239species only have3distributionpoints and only13species distribute more than half of the116areas. Analysis showsthat there may be a lack of research data or species identification errors in the formerfloristic studies of bryophytes in China.3.According to distribution of64families in the116areas and cluster analysisand sequence analysis on families, Pterobryaceae, Rhizogoniaceae, Hookeriaceae,Lembophyllaceae, Hypopterygiaceae, Neckeraceae, Sematophyllaceae,Trachypodaceae, Phyllogoniaceae, Racopilaceae, and Cryphaeaceae are typical families in the tropical zone;18families are the typical families in the temperaturezone, such as Meeseaceae, Fontinalaceae, Buxbaumiaceae, Tetraphidaceae,Timmiaceae, Encalyptaceae, Splachnaceae, Aulacomniaceae, Climaciaceae,Bryoxiphiaceae, Andreaeaceae, Leucodontaceae and Amblystegiaceae. Thanks to thegeographic information system, this paper takes the species of families as the indicatorto visually display the distribution pattern differences of64families in China.4. Based on species contained in the families and genera, the paper conductscorrespondence analysis and cluster analysis on116areas with the clusters anddiagrams visually reflecting the differences of families and genera compositiondifferences of bryophytes in different areas.116areas can be roughly divided into5distribution regions of bryophytes. Region1includes Pamirs, Kunlun Mountain,Bogda Mountain and Sanjianghe Drainage Basin, Xinjiang; Helan Mountain andShapotou, Ningxia; Qilian Mountain, Gansu; Sanhanwula, Hunshadake Sandy Land,Daqing Mountain and Qilaotu Mountain, Inner Mongolia; and Yunmeng Mountain,Hebei. This region reflects the typical flora in the arid region. Species contained in thePottiaceae account for36.08%of the total species, followed by Bryaceae occupyingfor11.1%. Region2includes Shimentai, Nanling and Dinghu Mountain, Guangdong;Wutong Mountain, Shenzhen; and Jianfenglin, Hainan. All these areas are located inthe tropical zone or the transition region from the tropical zone to the subtropical zonein South China. Families, including Pottiaceae, Hypnaceae, Dicranaceae,Sematophyllaceae, Fissidentaceae, Meteoriaceae and Neckeraceae, occupy the higherpercentages from12%to22.9%. Region3includes Changzhou, Nanjing, Yixing,Suzhou, Wuxi, Baohua Mountain, Zhenjiang, Jiaxing, Huzhou, Hangzhou, SheMountain, Hangjiahu Plain, Chongming Island and Nantong, Yangtze River DeltaRegion; Suqian, Huai’an, Yancheng and Xuzhou, North Jiangsu; Lao Mountain, LuMountain, Tai Mountain and Yi Mountain, Shandong; and Jigong Mountain, Henan.The average species number of the surveyed areas is comparatively small. This regionis the agricultural district with strong human disturbance or the area with arid environment. Families including, Pottiaceae, Brachytheciaceae, Bryaceae, Hypnaceae,Thuidiaceae, Entodontaceae, Mniaceae and Funariaceae, account for the higherpercentages. Region4includes Changbai Mountain, Wanglang, Taibai Mountain,Fuoping, Laotudingzi, Baishilazi, Tiao River and Bailong River Drainage Basin. Theseareas are all located in the northeast of China with rich species of bryophytes oftemperate zone. Brachytheciaceae, Pottiaceae, Hypnaceae, Mniaceae, Dicranaceae,Amblystegiaceae and Grimmiaceae occupy the higher percentages with the percentageof Brachytheciaceae reaching17.1%. Region5includes Yellow Mountain, AnhuiProvince; Baishanzu, Jiulong Mountain, Wuyanlin, Tianmu Mountain, DapanMountain, Fengyang Mountain, Qingliangfeng and Gutian Mountain, ZhejiangProvince; Jinggang Mountain, Jiangxi Province; Emei Mountain and Jinfo Mountain,Sichuan Province; Jiuwan Mountain, Guangxi Province; Fanjing Mountain andLeigong Mountain, Guizhou Province; Tongdao, Hunan Province; and Qiuyang,Chongqing Province. All these areas are located in Yangtze River basin with themonsoon climate, the abundant precipitation and high air humidity. With suchexcellent living conditions for most of bryophytes, there is the largest number ofspecies with the average species number per area reaching225. Hypnaceae,Brachytheciaceae, Dicranaceae, Pottiaceae, Meteoriaceae, Mniaceae, Bryaceae,Polytrichaceae, Thuidiaceae and Sematophyllaceae occupy the larger percentages.5. Conduct prediction on the distribution ranges of41genera of bryophytes underthe current climates and the conditions of climate warming (2070). It is found that theclimate warming will have a significant influence on the distribution of bryophytes inChina, receiving different responses from different bryophytes. Some genera oftemperature zone, like Bryhnia, Campylium, Diticha, Entodon, Eurohypnum, Grimmia,Haplohymenium, Herpetineuron, Homomallium, Lindbergia, Mnium, Plagiotheciumand Pohlia, have their suitable living area greatly shrunken under the conditions ofclimate warming; while, others lose their living areas. On the contrary, somecommunities distributing in the tropical zone, like Sematophyllum of Sematophyllaceae, will have their distribution range further expand to north ornorthwest areas. Some communities without clear distribution trends like Thuidium,Trichostomum and Weissia can well suit some arid areas like North China under thecurrent climate conditions. Under the conditions of climate warming, the distributionranges of these communities will increase instead of decreasing and their adaptabilitiesin the northeast of China also further improve.