祁连山地区维管植物区系特征

Floristic characteristics of vascular plants in Qilian Mountain region, China

关键词:  植物区系, 地理成分, R/T值, 生物多样性, 祁连山地区

Key words:  flora, geographical component, R/T value, biodiversity, Qilian Mountain region

摘要:

研究植物区系对植物资源保护及利用意义重大。祁连山地区作为生态过渡带具有丰富的植物多样性,但该区植物区系组成尚未得到系统化整理。为保证物种名录的准确性,探究植物区系分布状况,该研究通过对不同文献分散数据的搜集整理完成初步统计,利用植物标本信息进行校对以确定区系组成。结果表明:(1)祁连山地区共有维管植物1 952种,隶属108科527属,其中国家级保护植物44种,受威胁植物100种。(2)祁连山地区植物以草本为主,灌木次之,乔木最少,大多耐寒、耐旱,其中仅含1种植物的属数目最多,占比最大,区系地理成分多样且温带分布型占绝对优势。(3)祁连山东段物种丰富度最高,其次是中段,西段最少; 随经度西移,相似性指数下降。这表明物种组成及地理成分性质是当地气候条件、地形条件及多样化的生境类型综合作用的结果。(4)特有现象较为显著,共计中国特有种717种,祁连山地区特有种45种,反映该地区生态系统的独特性、多样性及复杂性。该研究结果为该地区物种多样性维持及资源可持续开发利用提供了本底资料及科学依据。

Abstract:

Vegetation plays a crucial role in the terrestrial ecosystem and can serve as a valuable indicator of environmental change. Studying the flora is of importance for protection and utilization of plant resources. Furthermore, understanding the composition and distribution of vegetation not only enhances plant biodiversity and quality but also enables us to make scientific use of plant resources. The ecological transition zone, known for its high species diversity, is an essential area for studying the flora. Qilian Mountain region, as an ecological transition zone, exhibits high plant diversity. However, the flora composition in this area has not been systematically documented. In order to ensure the accuracy of the species list and explore the distribution of flora, we conducted preliminary statistics by collecting and organizing scattered data from the literature. Subsequently, we used the plant specimen information to proofread and determine the flora composition. The results were as follows:(1)Qilian Mountains region had 1 952 species of vascular plants, belonging to 108 families and 527 genera, including 44 species of national protected plants and 100 species of threatened plants.(2)The dominant plant types in Qilian Mountain region were herbaceous, followed by shrubs, with trees being the least abundant. Most of these plants exhibited cold-resistance and drought-tolerance, with the majority being oligotrophic genera(the genera containing only one plant in Qilian Mountain region). The geographical components of the flora were diverse, but the temperate elements were predominant.(3)Species richness was the highest in the eastern region of the mountain, followed by the middle region, and the lowest in the western region. As longitude increased westward, the similarity index decreased. This suggests that the species composition and geographical components are synthetically influenced by local climatic conditions, topographic conditions, and diverse habitat types.(4)The presence of endemic species was significant, with a total of 717 endemic species in China and 45 endemic species in Qilian Mountain region, reflecting the uniqueness, diversity, and complexity of the ecosystem in the important region. In short, the flora of Qilian Mountain region is characterized by youthfulness. As an ecological transition zone, the region has extremely rich plant species diversity and breeds a large number of rare plants. Due to the large longitude span of the Qilian Mountain region, there are great differences in plant types between the eastern and western regions. The above results provide background data and a scientific reference for the maintenance of species diversity, sustainable development, and utilization of resources in this area.