Estimation of light-use efficiency of China’s midsubtropical planted coniferous forest based on flux measurements and spectral observations. Stem radius growth features of Picea meyeri and its relationship with environmental factors at the treeline of Luya Mountain A comparison of some eco-physiological characters of Calamagrostis angustifolia under variable and static water regimes Characteristics of Growth and Water Use of Robinia pseudoacacia under Different Soil Water Conditions