关键词: 养分回收效率, 气候因子, 土壤养分, 青藏高原东缘, 亚高山针叶林

Abstract: Understanding the characteristics of leaf nitrogen (N) and phosphorus (P) resorption efficiency is crucial for understanding nutrient cycling and plant nutrient use strategy in forest ecosystems. In this study, foliar and litter samples of 24 coniferous species were collected on the eastern Tibetan Plateau. Leaf N and P resorption efficiency of coniferous species was analyzed, combined with soil N and P contents and climatic data (mean annual temperature and mean annual precipitation). Our results showed that leaf N resorption efficiency was slightly higher than that of leaf P, indicating that coniferous species were generally Nlimited. The resorption efficiency of leaf N and P significantly differed with species, being the highest for Pinus species. Leaf N and P resorption efficiency showed a similar variation pattern along the environmental gradients, significantly decreasing with increased altitude, and increasing with increased average annual temperature, but showing no correlation with latitude and mean annual precipitation. With increasing soil N and P contents, leaf N and P resorption efficiency exhibited a significantlydecreasing trend, indicating that trees can improve nutrient resorption efficiency to reduce their dependence on soil nutrient limitation. From the perspective of nutrient resorption efficiency, this study enhances the cognitive level of ecological adaptation strategies and nutrient storage mechanisms of alpine plants in a changing environment.

Key words: nutrient resorption efficiency, climate factor, soil nutrient, eastern Tibetan Plateau, subalpine coniferous forest.