Abstract: The reproductive allocation of 12 Saussurea macrota Franch. populations at different elevations in eastern QinhaiTibetan Plateau was studied in this paper. The results showed that: （1) With the increase of elevation, the individual size of S. macrota decreased, and it invested more resource in reproductive organs to ensure sexual reproduction. （2) The floral traits of S. macrota changed with elevation, ensuring pollination effectively. （3) The seeds number of S. macrota decreased, while the 100seed weight increased with rising the elevation. Meanwhile, the numbers inflorescence and tubulous flower decreased but their weights increased with the increase of elevation. Therefore, the tradeoff is a common phenomenon in the organs of S. macrota.

Key words: biochar, crop growth, combined application of biochar and fertilizer, synergistic effects, roots, gene regulation