Nutrient Contents of Main Plough-land in Shandong Province and Their Analysis of Spatial Variability
ZHANG Ying-peng, LI Yan, YU Ren-qi, SUN Ming
ACTA AGRICULTURAE BOREALI-SINICA . 2008, (S2): 310 -314 .  DOI: 10.7668/hbnxb.2008.S2.072