洞庭湖湖滩矮埂保水生态灭螺水域育珠性能的试验研究

EXPERIMENTAL RESEARCH ON THE PERFORMANCE OF PEARL CULTURE IN THE LOW DIKE RETAINING WATERS FOR ECOLOGIC ELIMINATING SNAIL (ONCOMELANIA) OF THE LAKE BEACH OF DONGTIN LAKE

在湖滩矮埂保水生态灭螺水域中,进行育珠性能试验研究的结果表明,本水域特别对三角帆蚌具有优良的育珠性能;在冬、春两季湖滩落水干枯期间,矮围能保水50cm以上,活螺和螺卵淹死率达100％。

An experiment of the pearl culture was made in the low dike retaining waters and ecologic eliminating snail (Oncomelania) of the lake beach of Dongtin Lake. The result shows that the waters are of favourable conditions for the pearl culture. During the dropping in water level and the drying of the lake beach in winter and spring, the low dike can maintain a depth of above 50cm of water. Mortalities of living snail (Oncomelania) and snail egg may reach up to 100％. Under natural conditions, the plankton in the water body of the pearl culture amounts to 30000 indivduals/L; dissolved oxygen 9.54—9.74mg/L, Ca^(2+). concentration 44.9±0.06mg/L; pH value 6.9±0.13, H_2S and CH_4 0 value in the water body of the pearl culture when water temperature is at 20℃. These states of the water chemistry and biology are suitable for the requirement of the mussel (Hyriopsis cumingii) growth. Production rate of the pearl of excellent quality may reach to 41.3％, being 13.5％, 15.9％ and 23.4％ higher than that of the inland lake (27.8％), mute river (25.4％) and pond (17.9％) respectively.