资源环境科技发展态势分析平台

Variations in carbon (C), nitrogen (N) and phosphorus (P) stoichiometry and nutrient resorption during stand development are essential indicators for assessing forest degradation. Yet, their patterns along a chronosequence have been inconsistent. In this study, we analyzed the patterns of tree (leaf, branch, and root) C, N, P stoichiometry and nutrient resorption along a chronosequence of Metasequoia glyptostroboides forests (young forests: 7-, 12-year old; middle aged forests: 22-, 28-year old; and mature forests: 33-, 37-year old) in subtropical coastal China. We found that no significant trend was displayed along the chronosequence for both tree N concentrations and N resorption efficiency (NRE). Both tree P concentrations and P resorption efficiency (PRE) were higher, while tree C:P, and N:P were lower in young forests than those in middle-aged and mature forests. These results suggested that tree P stoichiometry and PRE were most strongly associated with forest degradation. Leaf P stoichiometry (P concentration, C:P, and N:P) was impacted more by soil stoichiometry, and leaf P concentration and N:P increased exponentially along soil P concentration and N:P, respectively. While branch, root P stoichiometry and PRE were affected more by tree age. Overall, our findings suggested that P deficiency was the leading factors, in terms of nutrients, for the M. glyptostroboides forests degradation in coastal China.