Evaluation of virtual water flow associated with agricultural trade between China and Africa and implications for water saving between China and Africa Assessment of eco climatic suitability and climate change impacts of/on broad leaved Korean pine forest in Northeast China Effects of Limited Supplemental Irrigation on Potato in the Semiarid Areas of Middle Gansu Province ANALYSIS AND EVALUATION OF SOIL WATER CONDITIONS OF PROTECTIVE FOREST ECOSYSTEM IN LOESS AREA Water and Heat Effect of Different Ground Coverings in Zanthoxylum bungeanum Plantation