The effects of phylogeny, life-history traits and altitude on the carbon, nitrogen, and phosphorus contents of seeds across 203 species from an alpine meadow

Abstract

Seed reserves are very important to the earlier growth and survival of plants, and its variation in nutrient contents might make species to form different germination or seedlings growth strategies. Here, 203 species collected from an alpine meadow on the northeastern Qinghai-Tibet plateau were used to test the effects of phylogenetic groups, life-history traits, and altitude on carbon (C), nitrogen (N) and phosphorus (P) contents of seeds across species. The results showed that (1) seeds of Brassicaceae had the highest C content, those of Fabaceae had the highest N content, and Asteraceae had the highest P content, and family explained independently 32.7%, 46.4%, and 17.9% of the variation in C, N, and P contents of seeds, respectively; (2) the smaller seeds tended to have higher C and P contents, and seed mass explained independently 2.5% of variation in C, 4.3% in N, and 8.1% in P contents; (3) N content was explained 1% independently by life form, seeds N content of perennials was significantly higher than that of annals, but seeds C and P contents had non-significant difference between them; (4) seeds of wind-adapted species had higher N and P contents, and dispersal mode explained independently 1.7% of variation in C, 1.6% in N, and 5.6% in P contents; (5) seeds from high altitude had the highest N and P contents, and altitude explained independently 4.3% of the variation in N and 4% in P contents.