中国苔藓植物特有种的地理分布格局
关键词:
急尖长苞冷杉,
,
活立木,
,
死亡木,
,
点格局分析
Abstract: Currently, endemic plants’ geographical distribution pattern and formation mechanism are the main research content of ecology. In this paper, data of endemic bryophytes information, spatial factors, weather factors, habitat heterogeneity factors from 28 provinces in China were used for analysis. We eliminated the spatial autocorrelation of the spatial data and adopted regression analysis and variance decomposition to analyze the relationships between ecological factors and the richness of endemic mosses (MRN), liverworts (LRN) and bryophytes (BRN). We analyzed the degree of interpretation of space model, environmental model and habitat heterogeneity model to the distribution pattern of MRN, LRN and BEN. The results showed that: (1) Chinese bryophytes’ richness distribution pattern showed significant regional differences, with higher richness in areas with great elevation gradient, such as QinghaiTibet and YunnanGuizhou Plateau. LRN and MRN were the highest in Yunnan, reaching up to 146 and 79, with lower richness in areas with small elevation gradient and less rainfall. Spatial location and topography influence the formation of endemic species. (2) MRN, LRN and BRN had strong spatial variability and their variation tendency was similar: at small scales (<600 km), MRN, LRN and BRN showed obvious positive correlation, however, when the scale reached about 2800 km, they showed maximum negative correlation and were characterized by significant latitudinal gradient; (3) MRN’s geographical distribution pattern mainly depended on habitat heterogeneity (complex terrain conditions) and spatial factors. At large spatial scale, location determined the theoretical value of MRN of a given area, while habitat heterogeneity and climate factors adjusted the MRN slightly. However, the geographical distribution patterns of LRN and BRN were mainly affected by climate and habitat heterogeneity.
Key words:
Abies georgei var. smithii,
living stem,
dead wood,
point pattern analysis.