Responses of Nitrogen, Phosphorus and Potassium Contents and Stoichiometric Characteristics of Fraxinus malacophylla Seedlings to Shading

• WEI Xinglan, 
• JING Huizhu, 
• CHA Xiaofei, 
• GUO Huanxian, 
• ZHANG Mei, 
• SUN Lijuan, 
• DONG Qiong