Study Of Cave Flora And Garden Plant Resources In Karst Cave In Guangdong

The karst caves are mainly distributed in north and northwest of Guangdong with large distribution areas and unique karsts landform.Consequently,Rich Caveresources have attracted many experts to study in Guangdong.Based on the field survey,literature references and identification of specimens,we studied the floristic composition,characteristics and rare endangered plants in karsts caves.Finally,wild ornamental plant resources were evaluated by AHP in order to select plants species which are suitable for vertical greening and indoor ornementation.The main results are as follows:1.There are 324 species(including subspecies and varietas,with the same below),belonging to 176 genera and 83 families of vascular plants in karsts cave of Guangdong.There are 74 species of Pteridophytes belonging to 25 genera and 14 families,as well as250 species of angiosperms belonging to 151 genera and 69 families.No Gymnosperms was recorded.2.As for Pteridophytes,dominant families included Pteridaceae,Dryopteridaceae,Selaginellaceae,Thelypteridaceae and Adiantaceae.The distribution types of families are mainly tropical,which covered 68% of the total Pteridophytes species.The most important genera are Pteris,Selaginella,Cyclosorus,Adiantum,Cyrtomium and Adiantum,and species of them contribute 59.46% of the total Pteridophytes species.The distribution types of genera were mainly tropical,accounting for 94.74% of all the types.Therefore,the composition of Perridophytes flora in karsts cave in Guangdong is tropical rather than temperate on both families and genera rank.3.As for Angiosperms,dominant families included Gesneriaceae,Urticaceae,Moraceae,Papilionaca,Acanthaceae,Vitaceae,Euphorbiaceae,Cucurbitaceae.The tropical types are dominant in the distribution Angiosperms families,which included 42 and covered 98.37% of all the types.The most important genera were Ficus,Chirita,Solanum,Pilea,Elatostema and Trichosanthes,the distribution type of which were mainly tropical,including 104 and covering 76.47% of all the types.As a consequence,the composition of Angiosperms flora in karsts cave in Guangdong is tropical rather than temperate on bothfamilies and genera rank.4.Compared with that in Guangxi,the karst cave plants in Guangdong had a higher degree of similarity at the genera level and families level in Pteridophytes.The similarity coefficient of the families and genera was 85.71% and 64% respectively.However,there was a large difference among species and the similarity coefficient accounted for 25.68%.As for angiosperms,the results showed strong similarities among families(82.61%),genus(94.70%)and species(69.60%),which reflected the close connection between the occurrence and development of flora in the two ares.5.There are 2 species of National Endangered Plants in the karsts caves in Guangdong,belonging to 2 families and 2 genera.Among them,Primula tabacum is a national endangered species that is endemic to China.According to IUCN's Standards of Endangered Species and the rest condition,we strongly suggested that Chirita orthandra,Begonia fimbristipula,Petrocodon Dealbatus,Saxifraga daqiaoensis and Gynostemma Pentaphyllum are listed in the List of wild plants under state.Finally,the main threats which the karsts caves faced in Guangdong were analyzed and related protection measures were proposed.6.There are 252 species of wild ornamentals in the karsts caves in Guangdong,belonging to 80 families and 157 genera.Among them,there are 47 species of Pteridophytes belonging to 13 families,21 genera,accounting for 18.65% of the total number of wild ornamental plants;there are 205 species of angiosperms,including 67 families,136 genera,accounting for 81.35% of the total number of wild ornamental plants.The wild ornamental plants are very abundant in the karsts cave of Guangdong and dominated by few-species(genus)and single species(genus).At the family level,the most abundant species were Gesneriaceae and Ricinaceae.There were 39 species,accounting for15.47% of the total number of wild ornamentals.At the level of the genera the ornamental plants in the karsts caves in Guangdong were dominated by single genera and few-species.Additionally,there are 152 genera,including 220 species,which accounted for 87.13% of the total species.Among them,the dominant genera are Pentiana,Pteris,Selaginella and Liriola,which belonged to the main groups of the karsts caves wild ornamental plants.According to the life forms of the wild ornamental plants,they were divided into 5categories,including ornamental ferns(47 species),ornamental trees(26 species),ornamental shrubs(26 species),ornamental herbs(104 species)and ornamental vines(49species).Within them,ornamental herbs and ornamental vines were dominant and the main group of wild ornamental plants in the krasts caves accounted for 41.27% and 19.44% ofthe total number of wild ornamental,followed by ornamental ferns,18.65% of the total number of wild ornamental plants.According to the use types of gardening,wild ornamental plants were divided into 8 categories,including shade trees(22 species),ground cover(25 species),herbaceous flowers(85 species),hedge plants(28 species),bedding plants(37 species),courtyard Greening plants(21 species),vertical greening plants(42species),indoor plants(72 species),which accounted for 8.73%,9.92%,33.73%,11.11%,14.68%,8.33%,16.67% and 8.57% of the total species of wild ornamental plants,respectively.According to actual field survey and cultivation experiments,44 species of plants suitable for vertical greening and 63 species of wild ornamental plants suiable for indoor foliage plants were initially selected.Accroding to the analytic hierarchyprocess,we analyzed the selected plants and then sorted them by the score.The result showed that priority was given to the development of vertical greening plants such as Parthnocissus laetevirens,Gynostemma pentaphyllum,Illigera celebica,Tinospora sinensis,Tetrastigma hemsleyanum,Stephania japonica,Cayratia japonica,Cyclosorus parasiticus,Adiantum capillusveneris,Ficus pumila,Pueraria lobata and so on.While priority was given to the development of indoor foliage plants such as Chirita villosissima,Saxifraga daqiaoensis,Alocasia macrorrhiza,Begonia leprosa,Begonia palmata,Begonia fimbristipula,Chirita pseudoheterotricha,Primulina argentea,Asplenium prolongatum,Amorphophallus rivieri and so on...