Studies On Taxonomy, Flora And Geography Of Pottiaceae (Musci) In Wudalianchi,China

Pottiaceae is widely distributed all over the world and has the largest number of genera in the Bryopsida, Musci, Acrocarpus, especially in the temperate and arid regions. So far,87 genera of the Pottiaceae have been known in the world; and 39 genera,179 species and varieties of Pottiaceae are in China. Systematic study of the Pottiaceae experienced a tortuous process, but at present many scholars accept the Zander classification system, This article according to the classification system. Wudalianchi volcanoes are located in Heilongjiang Province, consisting of 14 volcanoes and five lakes. This has caused to create a special ecological environment, and ideal destination for vegetation succession and species adaptation to a harsh environment. Most species of Pottiaceae adapt to the dry environment, and occupies the dominant position. In the Wudalianchi Nature Reserve they belongs to the dominant families, distribution accounted for a considerable advantage, also plays an important role in the composition of bryophyte flora, Therefore it is great significance to study Pottiaceae in Wudalianchi.More than 3000 bryophytes specimens were collected from Wudalianchi volcanoes, it’s present in 15 genera and 31 species and varieties. Didmodon bartramii is discovered in China for the first time,4 genera and 20 species and varieties were new to Heilongjiang Province. The new records has shown the enriched diversity of Pottiaceae in Heilongjiang Province. The family is divided into six major plants geographical elements:North Temperate elements, East Asia elements, Cosmopolitan elements, Asian and North American elements, Pan tropical elements and Old World Temperate elements. North Temperate elements and East Asia elements in China are dominated and accounted for 36% and 28%, repectively. These results show an obvious north temperate trait and typical East Asian characteristic.The results show that Pottiaceae is mostly distributed on Mt. Huoshao and Mt. Heilong, and distributed on Mt. Wei at least. We found that the number of species of Pottiaceae have trended down from new volcanoes to old volcanoes. According to results found on the Wudalianchi volcanoes growth substratum and moisture conditions are divided into 7 types according to their habitat. The relative frequency statistics and species diversity shows the order are arranged from high to low as following:humicolous habitat, chasmophilos habitat, lithophiious habitat, corticolous habitat, scoriaceous habitat, Saprophytic habitat and helobious habitat.The main objectives are to identify the species of Pottiaceae which distributed in Wudalianchi with colored pictures on its morphology, genus and species-level keys. Studies found the species of Pottiaceae in Heilongjiang Wudalianchi can inform us of species in this family more accurately and determine the floristic composition and characteristics, They can help summarize the typical features of all species as well as provide information for the classification of Pottiaceae in China.