Monitoring downstream migrations of Eriocheir sinensis H. Milne Edwards, 1853 (Crustacea: Brachyura: Grapsoidea: Varunidae) in the River Thames using capture data from a water abstraction intake

Chinese mitten crabs (Eriocheir sinensis) have been described as an alien invasive species in the River Thames, United Kingdom, and elsewhere in Europe. The crabs can cause considerable physical damage to the riverbeds and threaten native ecosystems. Trapping has been considered an option, but such attempts to control mitten crab populations in Germany in the 1930s failed. In the United Kingdom, it has been suggested that commercial exploitation of the species could be employed as a control option. This study was conducted as part of a larger program to assess the suitability of a commercial Chinese mitten crab fishery in the River Thames. Crabs and water samples from the River Thames between 2003 and 2006 were examined for the human pathogenic bacterium Vibrio parahaemolyticus. All samples throughout this testing period were positive for V. parahaemolyticus. The putative pathogenicity markers, thermostable direct hemolysin and thermostable direct–related hemolysin, were detected in one sample, indicating that the crabs possessed the potential to cause V. parahaemolyticus–associated illness if consumed without further processing. Levels of V. parahaemolyticus were higher during the summer than in the winter. This is the first study of V. parahaemolyticus prevalence in European-adapted Chinese mitten crabs.

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Влияние экологического состояния водоисточника на режим работы водопроводных очистных сооружений

Vodosnabzhenie i sanitarnaia tehnika ◽

10.35776/mnp.2020.03.03 ◽

2020 ◽

Author(s):

P. Bykova ◽

I. Egorova ◽

A. Strelkov ◽

L. Talovyria ◽

O. Nesterenko ◽

...

Keyword(s):

Water Quality ◽

Water Reservoir ◽

Water Source ◽

Optimal Dose ◽

Source Water ◽

Regulatory Requirements ◽

Water Quality Control ◽

Water Abstraction ◽

The City

При изучении качества воды источника водоснабжения г. Самары Саратовского водохранилища особое внимание было уделено основным показателям, влияющим на выбор реагентной обработки: мутность, перманганатная окисляемость и цветность. Сезонные изменения качества воды водохранилища требуют постоянной корректировки дозы реагентов с целью достижения нормативных требований к качеству очищенной воды. Приводятся результаты производственных исследований изменения качества воды Саратовского водохранилища в створе водозаборов г. Самары за 20172019 годы по мутности, перманганатной окисляемости и цветности. В связи с аномальными температурными перепадами и наступлением осеннего паводка (конец декабря 2019 г. и январь 2020 г.) резко изменилось качество воды водохранилища по цветности и перманганатной окисляемости. Отмечено, что увеличение указанных показателей потребовало повышения дозы реагентов при очистке исходной воды. Оптимальная доза реагентов постоянно коректируется в зависимости от состава исходной воды на флокуляторе Lovibond ЕТ-750 . Регулярное проведение пробного коагулирования позволило поддерживать качество очищенной воды в соответствии с нормативными требованиями СанПиН 2.1.4.1074-01 Питьевая вода. Контроль качества , кроме цветности и железа общего, так как превышение этих показателей наблюдалось в пределах погрешности методов измерения.While studying the water quality of the water source of the city of Samara the Saratov water reservoir, special attention was paid to the main indicators that influence the choice of chemical treatment: turbidity, permanganate index and color. Seasonal changes in the water quality of the water reservoir require constant adjustment of the chemical dose in order to meet the regulatory requirements to the quality of treated water. The results of the studies of changes in the water quality of the Saratov reservoir at the water abstraction points of the city of Samara for 20172019 by turbidity, permanganate index and color are presented. Due to the abnormal temperature differences and onset of autumn flood (end of December 2019 and January 2020), the water quality in the water reservoir dramatically changed in color and permanganate index. It was noted that an increase in these indicators required an increase in the dose of chemicals during the source water purification. The optimal dose of chemicals is selected with Lovibond ET-750 flocculator depending on the composition of the source water. Regular test coagulation allowed maintaining the quality of purified water in accordance with the regulatory requirements of SanPiN 2.1.4.1074-01 Drinking water. Quality control , except for color and total iron since the values of these indicators were increased within the measurement accuracy.

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