1. Ecological niche and in-situ control of MIB producers in source water
- Author
-
Ming Su, M D Suruzzaman, Jianwei Yu, Jinping Lu, Yiping Zhu, Min Yang, and Yu Zhang
- Subjects
0106 biological sciences ,Microcystis ,Environmental Engineering ,010501 environmental sciences ,Cyanobacteria ,01 natural sciences ,Water Purification ,Water column ,Nutrient ,Aquatic plant ,Environmental Chemistry ,neoplasms ,Ecosystem ,0105 earth and related environmental sciences ,General Environmental Science ,Ecological niche ,biology ,Drinking Water ,010604 marine biology & hydrobiology ,Environmental engineering ,General Medicine ,biology.organism_classification ,Water level ,Odor ,Odorants ,Environmental science ,Oscillatoriales - Abstract
Odor problems in source water caused by 2-methylisoborneol (MIB) have been a common issue in China recently, posing a high risk to drinking water safety. The earthy-musty odorant MIB has an extremely low odor threshold (4–16 ng/L) and is hard to remove via conventional processes in drinking water plants (DWP), and therefore could easily provoke complaints from consumers. This compound is produced by a group of filamentous cyanobacteria, mainly belonging to Oscillatoriales. Different from the well-studied surface-blooming Microcystis, filamentous cyanobacteria have specific niche characteristics that allow them to stay at a subsurface or deep layer in the water column. The underwater bloom of these MIB producers is therefore passively determined by the underwater light availability, which is governed by the cell density of surface scum. This suggests that drinking water reservoirs with relatively low nutrient contents are not able to support surface blooms, but are a fairly good fit to the specialized ecological niche of filamentous cyanobacteria; this could explain the widespread odor problems in source water. At present, MIB is mainly treated in DWP using advanced treatment processes and/or activated carbon, but these post-treatment methods have high cost, and not able to deal with water containing high MIB concentrations. Thus, in situ control of MIB producers in source water is an effective complement and is desirable. Lowering the underwater light availability is a possible measure to control MIB producers according to their niche characteristics, which can be obtained by either changing the water level or other measures.
- Published
- 2021