鄱阳湖自然保护区蚌湖和中湖池苦草冬芽的调查

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

1998年 1 2月对鄱阳湖自然保护区内蚌湖和中湖池苦草冬芽进行调查。苦草生活冬芽的平均长度为 3 .0 5± 0 .5 6 cm,平均直径为 0 .84± 0 .1 4cm,平均鲜重为 1 .0 3± 0 .3 0 g,平均干重为 0 .3 0± 0 .1 0 g,含水量为 70 .6 2 %。生活冬芽在蚌湖和中湖池的平均密度分别为 1 5 .8个 /m2和 2 4 .3个 /m2 。苦草冬芽在蚌湖的分布比较均匀 ,在中湖池各采样点的分布有显著差异 ,这种差异与不同采样点的基质状况有关。苦草生活冬芽在基质中分布最大深度为 3 5 cm,在0— 1 0 cm土层中所占比例最大 ;冬芽死亡数以 2 0— 3 0 cm土层中所占比例最大。冬芽分布深度对其以后的萌发有重要影响。

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±0.56cm and 0.84±0.14cm, respectively, and its average weight is 1.03±0.30g FW or 0.30±0.10g 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.