Inter-Specific Correlations among Dominant Populations of Woody Syringa reticulata Communities in Wulu Mountain Nature Reserve, Shanxi Province of China Interspecific Relationships Among Woody Plants of Forest Communities in Pangquangou National Nature Reserve at Mt. Guandi,Shanxi,China Interspecific Associations of Dominant Plant Populations in Secondary Forest of Pinus armandii in Qinling Mountains The effect of traveling on the interspecific correlation of dominant populations in Lishan subalpine meadow,Shanxi Province INTER-SPECIFIC CORRELATIONS AMONG DOMINANT POPULATIONS OF TREE LAYER SPECIES IN EVERGREEN BROAD-LEAVED FOREST IN JIULIANSHAN MOUNTAIN OF SUBTROPICAL CHINA