Practice of Establishing Aquatic Vegetation in Lake Lianhuahu in Wuhan,China Effects of snail herbivory on interspecific relationship between Elodea nuttallii and Vallisneria spiralis Effects of mechanical damage on the growth of Elodea nuttallii Effects of uniconazole on the growth and activities of anti-oxidation enzymes of Elodea nuttallii Stresses of Eutrophic Lake Sediment on Submersed Macrophytes Ι.Effects of Acetic Acid on Germination and Bud Growth of Elodea nuttallii and Potamogeton crispus