This study investigates responses in the leaf anatomy of Black Locust (Robinia pseudoacacia L.) to the atmospheric pollutants, SO2, NO2 and O3 and climate in Tehran. The anatomical variables studied include thickness of the leaf lamina and of its main constituent tissues and the length and density of stomata. We present evidence that, in response to urban… (More)
Based on an eigenvalue analysis, a new proof for the sufficient descent property of the modified Polak-Ribì ere-Polyak conjugate gradient method proposed by Yu et al. is presented .