Photosynthesis light response characteristics of subtropical tree species seedlings under different irradiances Steady-state and dynamic photosynthetic performance in the shade-demanding plant Amorphophallus xieiunder different levels of growth irradiance Acclimation of foliar photosynthetic apparatus of three tropical woody species to growth irradiance EFFECT OF IRRADIANCE AND WINTER TEMPERATURE ON PHYSIOLOGICAL PROPERTIES OF LEAVES OF THREE SUBTROPICAL TREES EFFECT OF GROWTH IRRADIANCE ON STABLE CARBON ISOTOPE RATIO, INTERCELLULAR COsub>2 CONCENTRATION AND WATER-USE EFFICIENCY OF TWO WOODY PLANT IN SUBTROPICAL NATURAL FOREST