紫外线法对压载水中淡水藻的灭活效果研究

The inactivation efficiencies of UV-C on microalgaes in ballast water

摘要:

按照《船舶压载水和沉积物控制和管理国际公约》对岸基测试试验的要求，采用准平行光束仪对8种淡水藻辐射，黑暗环境培养5d，确定剂量反应关系，研究紫外线对它们的灭活效果及特点。结果表明，紫外线法对梅尼小环藻、谷皮菱形藻、小球衣藻和铜绿微囊藻具有一定的灭活效果，灭活率随着紫外线剂量的增加而提高；小剂量的紫外线会刺激镰形纤维藻和斜生栅藻细胞生长，在剂量大于300 mJ/cm2时藻细胞的数量开始缓慢减少；剂量小于400 mJ/cm2时对钝脆杆藻和卵形隐藻没有灭活效果。紫外线对淡水藻的灭活效果较差。藻细胞个体大小不是影响紫外线灭活效果的原因，藻的种类、藻细胞壁的有无及其成分的不同可能是造成不同灭活效果的原因。

Abstract:

According to the base test requirements of ‘International Convention for the Control and Management of Ships in Ballast Water and Sediments’, the collimated light beam was employed to irradiate eight species of microalgae, and to investigate on the inactivation efficiencies of UV-C on them in a dark cutivation environment. The results showed that UV-C had some inactivation efficiencies on Cyclotella meneghiniana Kutz, Nitzschia palea., Chlamydomonas microsphaera and Microcystis sp., the inactivation rate increased with the increasing of UV-C doses. Low dose of UV-C could stimulate the growth of Ankistrodesmus falcatus and Scenedesmus obliquus. When the dose was improved to more than 300 mJ/cm2, algal cell numbers started to decrease. UV dosage less than 400 mJ/cm2 presented low inactivation efficiencies on Fragilaria capucina and Cryptomonas ovata Her. Therefore, the inactivation efficiencies by UV-C on microalga were relatively low. In addition, the algal cell size was found not one of the factors influencing on the UV-C inactivation efficiencies. The algal species, the existence and inexistence of the algal cell wall, and the difference components of algal wall might be the main factors influencing on the different inactivation efficiencies.