The role of ectomycorrhizal fungi in alleviating pine decline in semiarid sandy soil of northern China: an experimental approach Jiao-jun Zhu, Feng-qin Li, Mei-ling Xu, Hong-zhang Kang and Xiang-yun WuAnn. For. Sci., 65 3 (2008) 304DOI: https://doi.org/10.1051/forest:2008007