Study On The Functional Traits Of Quercus Species And Their Relationships With Environmental Factors In Temperate Zone Of NSTEC

Geographical distribution of classical plant functional traits from main tree species in Temperate zone of NSTEC were studied in this paper. Quantitative characteristics and variation ranges of functional traits from Quercus trees were revealed. The relationships among plant functional traits and their response relations with environmental factors (meteorological factors and soil factors) were analyzed. Finally, environmental driving factors for geographical alternative distribution of Quercus trees in NSTEC were found and environmental driving mechanism were discussed to some extent.Functional traits of 55 deciduous trees (including the8 Quercus trees) from 11 core habitats(such as Maoershan, Changbaishan, Qingyuan, Caohekou, Laotudingzi, Huanren, Wulingshan, Xianrendong, Jiyuan, Luanchuan, Baotianman and so on) in the north-east and the north of China from July to October of 2006, such as LDMC, LMA and RBD were collected and analyzed. Meanwhile, Amax, leaf N, leaf P, leaf K and seed traits of 8 Quercus trees (Q.mongolica, Q.liaotungensis, Q.dentata, Q.aliena, Q.aliena var. acuteserrata, Q.serrata var. brevipertiolata, Q.variabilis, Q.acutissima) were collected and mainly analyzed. The relationships among plant functional traits and their relationships with environmental factors were analyzed quantitatively. The main results are as follows.(1)functional traits of Quercus trees that geographical distributed alternatively in NSTEC also distributed regularly to some extent, such as from south to north, along with geographical alternative distribution of Quercus trees from Quercus mongolica to Quercus variabilis, Nmass, Pmass and Kmass decreased respectively, while LMA increased adversely; along with geographical alternative distribution of Quercus trees from Quercus mongolica to Q.serrata var. brevipertiolata, Ammax and Aamax went down to some extent. Functional traits of Quercus trees had their own variation ranges. As for Quercus trees, LDMC ranged from 324.07 g kg^-1 to 449.94 g kg^-1, RBD ranged from 0.037 9 cm cm^-1 to 0.129 1 cm cm^-1, LMA ranged from 42.97 g m^-2 to 87.70 g m^-2, N_mass ranged from 1.113 g 100g^-1 to 3.085 g 100g^-1, N_area ranged from 0.568 g m^-2 to 1.996g m^-2, P_mass ranged from 0.157 g 100g^-1 to 0.341 g 100g^-1, P_area ranged from 0.075 g m^-2 to 0.209 g m^-2, K_mass ranged from 0.553 g 100g^-1 to 1.050 g 100g^-1, K_area ranged from 0.361 g m^-2 to 0.627 g m^-2, A_max^m ranged from 230.60 nmolCO2g^-1s^-1 to 339.38 nmolCO2g^-1s^-1, A_max^a ranged from 10.39μmolCO2m^-2s^-1 to 18.62μmolCO2m^-2s^-1, seed mass without skin ranged from 0.47 g to 2.37 g. As for 55 deciduous trees, LDMC ranged from 170.47 g kg^-1 to 473.93 g kg^-1, LMA ranged from 23.28 g m^-2 to 125.71 g m^-2and RBD ranged from 0.018 9 cm cm^-1 to 0.129 1 cm cm^-1.(2)Along the gradient of environmental factors in NSTEC, plant adapted to environment through own functional trait combinations. From south to north, with the temperature dropped, growing period of Quercus trees went down, LMA (r=0.294, P=0.145) fell down, A_max^a (r=-0.647, P=0.059) and A_max^m (r=-0.454, P=0.219) increased, so plant could produce more dry mass to maintain its physiological behavior. Meanwhile, seed mass without skin of Quercus trees increased(r=-0.861, P<0.01) along with rising of latitude (decreasing of temperature) in order to improve seed survive rate; As to 55 deciduous trees, with decreasing of temperature, LMA(r=0.072, P=0.433) went down. Furthermore, RBD increased (r=-0.194, P<0.05; r=0.198, P<0.05) with decreasing of temperature and increasing of MASL (Mean annual sunlight) in order to improve bark's ability to defend cold and stronger light. As the rainfall changed, plant adapted to environment through adjusting LDMC(r=-0.490, P<0.01, Quercus trees; r=-0.391, P<0.01, 55 deciduous trees) and LMA(r=-0.603, P<0.01, Quercus trees; r=-0.192, P<0.05, 55 deciduous trees). In all environmental factors, meteorological factors played a more important role in the distribution of Quercus trees. As the sampling scale varied, main meteorological factors changed too. Water played a main role in the distribution of functional traits of Quercus trees in NSTEC, but temperature and water played main role in the distribution of functional traits of 55 deciduous trees in NSTEC. In all soil factors, organic matter and soil nitrogen content played main role in the distribution of functional traits of Quercus trees in NSTEC, but soil phosphorus content played an main role in the distribution of functional traits of 55 deciduous trees in NSTEC.(3)The relationship among plant functional traits were complicated relatively, such as, the relationships between LDMC and LMA were significant in not only Quercus trees(r=0.782, P<0.01) but also 55 deciduous trees (r=0.367, P<0.01); With LMA increased, A_max^a (r=0.674, P<0.05) and A_max^m (r=0.159, P=0.682) increased; As leaf N increased, A_max^a (r=0.472, P=0.200, N_area; r=0.215, P=0.578, N_mass) increased, but A_max^m didn't change; As N_area, P_area and K_area increased, LDMC(r=0.493, P<0.05;r=0.617, P<0.05; r=0.481, P<0.05) and LMA(r=0.685, P<0.01; r=0.769, P<0.01; r=0.717, P<0.01) increased; N_area, P_area and K_area were positively correlated with each other(r=0.721, P<0.01, N_area and P_area; r=0.704, P<0.01, N_area and K_area; r=0.801, P<0.01, K_area and P_area). Temperature and water were main driving factor of Quercus trees that geographical distributed alternatively in NSTEC. Plant responded to environmental factors'effect on it through variation of plant functional traits.