Comparison of the Stem and Leaf Morphological Structures of 18 Communities of the Foreign Plant Eupatorium adenophorum Comparison of Eupatorium adenophorum Heat Tolerances of Different Geographical Populations Allelopathic effects of Eupatorium adenophorum Spreng.on seed germination and seedling growth in ten herbaceous species Bioconcentration effects of Cd, Pb and Zn in soil-Eupatorium adenophorum Spreng-Procecidochares utilis Stone system Effects of Eupatorium adenophorum Sprengel invasion on Soil Enzyme Activities and Physical and Chemical Factors