Intraspecific variations of Castanopsis delavayi leaf traits and their relation ship with environmental factors

In order to explore the intraspecific variation of Castanopsis delavayi leaf traits and correlations between leaf traits and environmental factors, we investigated 11 C. delavayi populations across the distribution and measured six leaf functional traits including leaf thickness, leaf toughness, leaf area, specific leaf area, leaf dry matter content and leaf frost sensitivity. The results showed that the total intraspecific coefficient of variation of C.delavayi leaf functional traits was from 7.3% to 41.6%. The total intraspecific variation derived from populations,individuals and leaves, but the main source of intraspeci?c variation was population variation. Specific leaf area was significantly negatively correlated with leaf thickness and leaf dry matter content, but positively correlated with leaf area. Leaf toughness was significantly negatively correlated with leaf area and leaf dry matter content. Leaf area was mainly influenced by mean annual precipitation and longitude, the most important environmental factors affecting specific leaf area were mean annual temperature, mean temperature of coldest month and altitude. The results indicated that intraspecific trait variation was obvious in different C. delavayi populations, only an average trait value for species was not enough. Environmental conditions were the main factors affecting the intraspecific variation and different environmental factors had different effects on leaf traits.