青海地区草地早熟禾种质资源生态化学计量特征研究OA

To investigate the organ-specific variation in ecological stoichiometric characteristics of Poa pratensis L.under uniform environmental conditions,this study analyzed 19 wild P.pratensis germplasm resources collected from Qinghai.The contents and stoichiometry ratios of carbon(C),nitrogen(N)and phosphorus(P)in different organs(roots,stems,leaves,and spikes)of various germplasm resources were analyzed under identical growth conditions to evaluate the nutrient absorption,allocation strategies and environmental adaptability.The results revealed significant intraspecific variations in C,N,and P con-tents and their stoichiometric ratios in P.pratensis accessions,with the coefficient of variance in N and N/P ratios being the greatest.Elemental distribution patterns among organs revealed that C and N concentra-tions were higher in aboveground organs(stems,leaves,and spikes)than in roots;P concentration fol-lowed the order of stem>root>spike>leaf;the C/N ratios ranked as stem>leaf>root>spike,with aboveground organs overall exceeding belowground organs;and N/P ratios were significantly greater in roots compared with aboveground organs.Cluster analysis divided the germplasms into three distinct functional groups,in which a root-priority type is suitable for phosphorus-deficient soil remediation,a shoot-priority type is ideal for rapid vegetation establishment,and a reproduction-assurance type is adapted to nutrient-poor habitats.These results demonstrate the pattern of distinct stoichiometric among the differ-ent organs of Poa pratensis L.,provide new insights into alpine plant adaptation mechanism and essential reference data for ecological restoration and resource management.