Dry Soil Layer Forming and Soil Nitrogen Consumption Characteristic of Alfalfa Grassland in the Semi-humid Region of the Loess Plateau
WAN Su-mei, JIA Zhi-kuan, WANG Yong, HAN Qing-fang
JOURNAL OF NATURAL RESOURCES . 2008, (3): 383 -390 .  DOI: 10.11849/zrzyxb.2008.03.004