关键词: 低湿地, 植物区系, 维管植物, 毛乌素沙地

Abstract: The flora composition, geographical elements, life forms and water ecological groups of vascular plants in low wetland of the Mu Us Sandy Land were studied based on field investigation and by applying the methods of botany and phytogeography. The results show that the total of 323 species belongs to 59 families and 182 genera of vascular plant. The single-species family, few-species family, the single-species genera and few-species genera are the main part of the low wetland flora, and were the main source of flora complexity and species diversity. The dominance of the few-species genera is evident. In most cases, though the bigger species family and genera aren't the dominant species of low wetland plant community, they are the representative components of low wetland plant community, and they have an important influence on the flora structure and vegetable pattern. The geographic elements of the flora are of multiplicity and the temperate element is the main part of low wetland flora. The herbaceous plants have the numerical advantage. The perennial herbs as the main part of the herbaceous plant have an obvious effect on low wetland environment. The analysis of geographical element and distribution characteristic of vascular plant in low wetland of the Mu Us Sandy Land also indicates that the climate and environmental conditions, the ecological amplitude and the adaptive capacity of the plant have a determinative influence on the floristic geography distribution.

Key words: low wetland, flora, vascular plant, Mu Us Sandy Land