Multi-marker study of the responses of the Unio tumidus from the areas of small and micro hydropower plants at the Dniester River basin, Ukraine

The aim of this study was to evaluate the environmental impact of the hydropower plants (HPPs) utilizing the bivalve mollusk Unio tumidus. The upstream and downstream of the dam sites of small HPPs and micro HPPs were examined. The indices of stress and toxicity were determined in the digestive gland, hemocytes (lysosomal integrity) and honads (alkali-labile phosphates, ALP). The mollusks from the reservoirs of small HPPs show the depletion of the cholinesterase, the highest glutathione S-transferase, ALP (by ~5 times) and metallothionein levels, low concentration of glutathione, the highest extralysosomal activity of the cathepsin D (CTD), the loss of the lysosomal integrity and a high copper concentration, indicating pollution from agricultural and municipal wastes. The specimens from the micro HPP area had the highest level of glutathione and lipid peroxidation and a low Cu,Zn-SOD activity and low morphological indexes.

本研究旨在以双壳软体动物膨胀无齿蚌（Unio tumidus）为实验材料，评估水力发电厂（hydropower plants, HPPs）的环境影响。研究对小型与微型水力发电厂的坝址上下游区域开展了检测，测定了消化腺（digestive gland）、血淋巴细胞（hemocytes，溶酶体完整性（lysosomal integrity））以及生殖腺（gonads）中的应激与毒性相关指标，其中碱不稳定磷酸盐（alkali-labile phosphates, ALP）的检测针对生殖腺进行。小型水力发电厂库区的软体动物呈现出如下特征：胆碱酯酶（cholinesterase）耗竭，谷胱甘肽S-转移酶（glutathione S-transferase）、ALP水平最高（提升约5倍），金属硫蛋白（metallothionein）水平升高，谷胱甘肽（glutathione）浓度降低，组织蛋白酶D（cathepsin D, CTD）的溶酶体外活性最高，溶酶体完整性受损，且铜浓度升高，表明该区域受到农业与市政废弃物的污染。微型水力发电厂区域的标本则呈现出谷胱甘肽与脂质过氧化（lipid peroxidation）水平最高，铜锌超氧化物歧化酶（Cu,Zn-SOD）活性及形态学指标偏低的特征。