Trade-off between leaf traits in a burned area of Picea asperata-Abies fabri forest of the Qinghai-Tibetan Plateau

Abstract Climate change and disturbed are testing the resilience of forests worldwide, Exploring the adaptation strategies of plants in alpine regions could provide reliable suggestions for plant conservation. As an indispensable organ, the functional traits and correlations of leaves are most closely related to the environment, and are the main indicators to measure the suitability of plant survival. The scaling relationship of leaf mass, leaf area and leaf thickness in the area of fire site is still lacking. On the basis of survey data, we measured leaf traits and correlation of shrub in the burned area of Piceaasperata-Abies fabri forest of the Qinghai-Tibetan Plateau. Our results showed that: the families Salicaceae belong to quick investment-return, the Caprifoliaceae belong to slow investment-return. The scaling relationship of leaf fresh mass and leaf dry mass showed that the families Salicaceae and Saxifragaceae the scaling exponent (α) overlapped with one, means the change in leaf dry mass were proportional to the change in leaf fresh mass. For Gramineae was significantly greater than 1.0, while the Rosaceae and Caprifoliaceae was less than 1.0, which meant that the increase of leaf dry mass did not keep pace with the increase of leaf fresh mass in some species. The scaling relationship between leaf mass and leaf area was relatively complex, and α for all families did not include unity. The coefficients of determination (i.e. R2) for leaf fresh mass vs. leaf area were always greater than that of leaf dry mass vs. leaf area. The family Rosaceae, the 95% CI of the scaling exponent of the leaf area vs. leaf thickness relationship overlapped with one; the leaf area increased with increasing leaf thickness, the relationship did not show similar results in the other families. In future studies, we need more comprehensive data sets containing more species living under the fire site to assess the generality of the diminishing returns hypothesis. This will provide a new perspective to understand the adaptation of plants regenerated after the fire to harsh habitats.