水力负荷对滤池中蚯蚓生态生理适应性的影响

Ecological and Physiological Adaptabilities of Earthworm in Vermifilter Under Different Hydraulic Loading

针对不同的水力负荷胁迫,研究和分析蚯蚓在生物滤池中的生态生理适应性,对比各工况滤池中蚯蚓和受相同自然因素影响的人工养殖蚯蚓的生理指标.结果表明,水力负荷从2.4 m3.m-2.d-1提高到6.0 m3.m-2.d-1时,滤池中蚯蚓密度和单位面积蚯蚓生物量受水力负荷影响较小,虽呈缓慢减小趋势,但基本可分别保持在1.5×10^4条.m-2和3 kg.m-2,滤池的环境条件较适合蚯蚓的孵化繁殖.和人工养殖蚯蚓相比,该水力负荷范围内,滤池蚯蚓呼吸旺盛,摄食、消化、排泄等生态功效发挥良好,消化率可达35.31%~41.47%,显著高于人工养殖蚯蚓消化率（17.17%~25.95%）.但当水力负荷增大到6.7m3.m-2.d-1时,滤池蚯蚓的数量和生物量减少幅度均达1/3,自身的呼吸系统功能明显减弱,显著低于人工养殖蚯蚓的正常呼吸水平,且对污泥的代谢水平受到影响.为维持蚯蚓较好的生存环境,保证滤池正常的生态功效的发挥,推荐蚯蚓生物滤池运行水力负荷不宜超过6.7m3.m-2.d-1.

Ecological and physiological adaptabilities of earthworms in vermifilter were studied under different hydraulic loading,and physiological indexes of earthworms in different filter conditions were compared with that of artificial cultured earthworm with the same natural influencing factors.The results show that when hydraulic loading rises from 2.4 m3·m-2·d-1 to 6.0 m3·m-2·d-1,density and biomass in unit area of earthworms are affected by hydraulic loading slightly.Though,the two items take on a trend of slowly decrease, they can keep a level of 1.5× 10^4·m^-2 and 3 kg · m^-1 separately and the filter＇ s environment is favorable for earthworms to breed and hatch. While compared with artificial cultured earthworms, food-taken, digestion, excretion and other ecological functions are brought to excellent play in the case of this loading. What＇s more, the digestibility reaches to 35. 31% ~ 41. 47% which is markedly prior to that （17.17% ~ 25.95 % ） of earthworms in cow dung. However, when the hydraulic loading increases up to 6.7 m3 · m^-2 · d^-1, earthworm number and bio-quantity reduces 1/3 and respiratory system function has a notable decrease which is notably lower than that of artificial cultured earthworms, furthermore, metabolism level of sludge is influenced. In order to maintain a good living environment for earthworms to assure the exertion of ecological function, it is commended that the running hydraulic loading in earthworm vermifilter should not exceed 6.7 m3 · m^-2 · d^-1.