WINTER BUDS OF VALLISNERIA IN BANGHU AND ZHONGHUCHI, TWO LAKES IN POYANG LAKE NATURE SANCTUARY

The winter buds of Vallisneria Yan were investigated in Banghu and Zhonghuchi located in Poyang Lake nature sanctuary in Dec. 1998. The average length and diameter is 3.05?.56cm and 0.84?.14cm, respectively, and its average weight is 1.03?.30g FW or 0.30?.10g DW. Water content of the living winter buds is 70.62%. Average density of the living winter buds in Banghu Lake is 15.8m-2, and that in Zhonghuchi Lake is 24.3m-2. No significant difference was found in the densities among different sampling station in Banghu Lake. While in Zhonghuchi Lake it showed significant differences, which was considered to be related with the sediment type in different places. The number of living and dead winter buds at different sediment depth was investigated in Zhonghuchi Lake. The living winter buds at 0-10cm sediment depth comprised 44.68% of the total living buds, whereas the dead winter buds were found more frequently at 20-30cm. Sediment depth had strong affect on the germination of the living winter buds.