Responses of the urban roadside trees to traffic environment Responses of Stomatal Traits of Desert Plant Nitraria tangutorum Leaves to Artificially Simulated Precipitation Characteristics and dynamic changes of stomata on the hypocotyl of Brassica chinensis var.parachinensis Stomata-density changes of the plants in the Loess Plateau of China over last century Response of leaf of Nitraria tangutorum Bobr stomata characteristics to artificial simulation of rainfall