关键词: 生态化学计量特征, 苔藓, 土壤养分, 空间尺度, 环境因子, 齿肋赤藓(Syntrichia caninervis), 古尔班通古特沙漠

Abstract: Previous studies showed that moss stoichiometric characteristics were influenced by moss patch size, shrubs and the environment in the desert. The study of moss stoichiometry in different spatial distribution areas is crucial for an understanding of growth and adaptation strategy of the mosses. In this study, the dominant moss (Syntrichia caninervis) of biological soil crusts and soil under the moss patches in the Gurbantunggut Desert were selected to determine their stoichiometry in different dunes and sites. Moss stoichiometry and soil available nutrients were significantly influenced by different distribution areas except for moss C. The N_aboveground vs. N_belowground' P_aboveground vs. P_belowground and K_aboveground vs. K_belowground scaling exponents of moss were 0.251, 0.389 and 0.442, respectively. The N vs. P scaling exponents were 0.71, 0.84 in above- and below-ground parts of moss. Moss stoichiometry was disproportionately distributed in the above-ground and below-ground parts. Moreover, moss N, P and K elements were influenced by mean annual precipitation (MAP), longitude and soil nutrients. The nutrients of moss were affected by spatial distribution, mean annual temperature (MAT), MAP and soil nutrients. The growth of moss was limited by N element in the temperate desert. This study provides the stoichiometric characteristics of C, N, P and K of moss at different spatial scales and explores their relationships with environmental variables, which can help understand nutrient patterns and utilization strategy of N, P and K, and their potential responses to global climate changes in desert.

Key words: ecological stoichiometry, moss, soil nutrients, spatial scale, climate factors, Syntrichia caninervis, Gurbantunggut Desert