Comparison of specific leaf area,SPAD value and seed mass among subtropical tree species in hilly area of Central Hunan,China

Specific leaf area(SLA),SPAD value and seed mass are important plant function traits,reflecting light use capacity and seed dispersal pattern.In order to understand the differences of SLA,SPAD value and seed mass among main subtropical tree species,leaves of Quercus fabri,Litsea coreana,Liquidambar formosana,Choerospondias xillaries,Cyclobalanopsis glauca,Lithocarpus glabra,Pinus massoniana,Cunninghamia lanceolata,Ilex purpurea,Eurya muricata,Oropetalum chinensis and Symplocos caudata were sampled at top,middle and bottom of canopy position to determine SLA and SPAD values.At the same time,mature seed of 7 tree species were collected to measure dry mass.The results showed that specific leaf area and SPAD differed significantly among the 12 tree species.The highest SLA was found for deciduous broadleaved tree species,and the lowest for,conifers,broad-leaved evergreen tree species and shrubs had the intermediate SLA.For SPAD,broad-leaved shrubs had the highest value,followed by evergreen broad-leaved tree species,and deciduous t1ree species had the lowest values.SLA changed significantly with canopy position,but no significant was observed for SPAD at different canopy position.Among 12 tree species,SLA of L.formosana and L.glabra showed insignificant difference with canopy position,SLA of P.massoniana increased significantly but the other 9 tree species declined significantly with canopy position.Seed mass decreased in the order of C.axillaries,C.glauca,L.glabra,O.chinensis,L.coreana,C.anceolata,E.muricata dunn.There was nosignificant correlation between SLA and SPAD for shrub,but significant negative correlation for broadleaved trees.Seed mass did not relate to SLA and SPAD for all tree species.