Which of the following increases the BOD of water?
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Answer: D. Sugar mill effluents
Explanation
Biochemical oxygen demand measures the amount of dissolved oxygen needed by aerobic microorganisms to break down organic matter. Sugar mill effluents contain exceptionally high concentrations of dissolved sugars and complex organic carbon waste. Microorganisms rapidly consume this abundant organic food source, depleting dissolved oxygen and elevating water BOD. High biochemical oxygen demand is a primary indicator of severe organic water pollution in aquatic ecosystems. Industrial food processing plants generate wastewater loaded with biodegradable organic compounds. Oxygen depletion in rivers caused by high BOD levels leads to catastrophic fish kills and aquatic suffocation.
Environmental protection agencies mandate rigorous wastewater treatment for sugar mills before discharge occurs. Monitoring water BOD levels helps regulatory authorities enforce industrial clean water discharge compliance. Constructed wetlands are frequently utilized to biologically filter organic-rich industrial effluents before release. Algae produce oxygen during daytime photosynthesis, which temporarily lowers rather than increases water BOD. Sand is an inert mineral sediment that contributes no biodegradable organic matter to elevate biological oxygen demand. Moss consists of living plant material that generally contributes minimal dissolved organic waste compared to sugar effluents.
- Subject
- Agriculture
- Category
- Forestry
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- —
- Difficulty
- medium
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