| Summary: | Nitrogen (N) and phosphorus (P) resorption from senescing organs are important plant nutrient conservation mechanisms. However, whether nutrient resorption can indicate plant adaptation to nutrient-poor environment remains a controversy. We quantified nutrient resorption efficiency of major species in an alpine meadow of the Qinghai-Tibetan Plateau. N and P resorption for these species averaged 65.2% and 67.4%, respectively, which was at the high end of the values of global scale. Among three life forms, sedges contained least N and P and had highest resorption efficiency, indicating sedges had a competitive advantage over grasses and forbs in this nutrient-poor environment. This result was consistent with the fact that sedge was the typically dominant plant functional group in Qinghai-Tibetan Plateau. By fitting the allometric equations ([ nutrient](senescent) = A([nutrient](live))(B)) separately for N and P, we found much smaller B (N) than B (P), which suggested that relative to the resorption from senescent leaves, the cost of N uptake from soils increased more quickly than that of P as resource availability decreased. This phenomenon was contrary to the corresponding N and P acquisition pattern of the tropical ecosystem, which matched the large geographical gradients of N vs. P limitation (N for alpine ecosystem, while P for tropical ecosystem). This study suggests that surveying leaf nutrient concentration and resorption could provide indicative information about plant adaptation to nutrient-poor soil within and across ecosystems. Our finding offers insights to nutrient management and ecosystem restoration in nutrient-poor environment and delivers information for upcoming meta-studies and model simulation of global leaf nutrient resorption. Crown Copyright (C) 2012 Published by Elsevier B.V. All rights reserved. Nitrogen (N) and phosphorus (P) resorption from senescing organs are important plant nutrient conservation mechanisms. However, whether nutrient resorption can indicate plant adaptation to ...
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