关键词: 中国, 植被动态, 不对称性增温, 海拔

Abstract: A controlled potexperiment with different treatments of Cd and N concentrations was conducted to investigate the biomass production and accumulation and the distribution of N, P, K and Cd in Alnus formosana. The results indicated that the dry matter accumulation, N, P, K absorption and accumulation in roots, stems and leaves in A. formosana were significantly inhibited under Cd stress without adding N; the N and K contents in roots and leaves were reduced, but there was no significant effect on P content. Under Cd stress, the A. formosana adapted to the Cd stress conditions by increasing proportions of N, P, K and dry matter in roots, reducing their proportions in leaves, and improving N and K use efficiency. The root was the main part of Cd enrichment, whose transfer coefficient ranged between 0.06 and 0.22. Cd stress decreased both transfer coefficient and enrichment coefficient of Cd in A. formosana. N addition increased the contents and accumulations of dry matter and N, K in roots, stems, and leaves of A. formosana under 30 mg·kg^-1 Cd stress, alleviated N, K absorption restrictions caused by Cd stress, but had no significant effect on P content and its accumulation. Also, N addition increased the proportion of dry matter in roots and root/shoot ratio, especially under 0.4 g·kg^-1 N application. Furthermore, the accumulation and proportion of Cd were increased in stems and leaves and decreased in roots. The Cd transfer factor (TF) and stem/leaf biological enrichment coefficients (BCF) increased, but the root BCF was observably reduced. Overall, N application improved A. formosana’s ability to adapt to the environment under Cd stress.

Key words: China, vegetation dynamics, asymmetric warming, altitude