华南阔叶树种幼苗叶片的养分特征

研究了阔叶树种幼苗山杜英、红锥、海南红豆、火力楠、红花油茶、枫香、黎蒴、米老排和樟树的N、P、K浓度和单位叶面积含量。结果表明，海南红豆、黎蒴和樟树的N、P、K浓度较高，而红花油茶、黎蒴和樟树的单位叶面积N、P、K含量较高，9种树种的上部和下部叶片的平均养分浓度分别为N16．67和17．09g·kg^-1，P1．29和0．84g·kg^-1，K11．77和6．65g·kg^-1，平均养分含量分别为N0．871和1．069g·m^-2，P0．065和0．052g·m^-2，K0．608和0．426g·m^-2，各树种上部叶片的P和K浓度和含量大于下部叶片，从养分含量的角度考虑，红花油茶与其他8种树种混交，红锥或米老排与山杜英、枫香、海南红豆、黎蒴、樟树混交，火力楠与黎蒴、樟树混交是合理的。

Nutrient characteristics in leaves of broadleaved seedlings in south China

Nutrient concentrations and contents in leaves of broadleaved Elaeocarpus sylvestris, Castanopsis hystrix, Ormosia pinnata, Michelia macclurei, Camellia semiserata, Liquidambar formosana, Castanopsis fissa, Mytilaria laosensis and Cinnamomum camphora seedlings were studied. Leaf N, P and K concentrations in Ormosia pinnata, Castanopsis fissa and Cinnamomum camphora were higher than those of other tree species, and leaf N, P and K contents in Camellia semiserata, Castanopsis fissa and Cinnamomum camphora were higher than those of other tree species. Mean leaf nutrient concentration in upper crown and lower crown of 9 tree species was N 16.67 and 17.09 g.kg-1, P 1.29 and 0.84 g.kg-1, K 11.77 and 6.65 g.kg-1, respectively. Mean leaf nutrient content in upper crown and lower crown of 9 tree species was N 0.871 and 1.069 g.m-2, P 0.065 and 0.052 g.m-2, K 0.608 and 0.426 g.m-2, respectively. Leaf P and K concentrations and contents in the upper crown were generally higher than those of the lower crown. From the view of nutrient contents, mixing Camellia semiserata with other tree species, mixing Castanopsis hystrix or Mytilaria laosensis with Elaeocarpus sylvestris, Liquidambar formosana, Ormosia pinnata, Castanopsis fissa, and Cinnamomum camphora, and mixing Michelia macclurei with Castanopsis fissa and Cinnamomum camphora were suitable.