A river with an inflow of domestic sewage rich in organic waste may result in:
Correct answer: B. Death of fish due to lack of oxygen.
- A. An increased production of fish due to biodegradable nutrients.
- B. Death of fish due to lack of oxygen.
- C. Drying of the river very soon due to algal bloom.
- D. Increased population of aquatic food web organisms.
Explanation
High amount of organic waste in a lake will trigger and activate decomposer microbes which will decompose organic waste. Biochemical Oxygen Demand (BOD) of this lake will shoot up and decomposers will utilize most of the dissolved oxygen present in lake. Consequently, the level of dissolved oxygen will go down to alarming extent. Aquatic animals like fish which totally depend on the oxygen dissolved in water will ultimately die.
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Ecosystems include biotic and abiotic components, food chains and webs, energy flow, nutrient cycles, populations and ecological relationships. Pollution and conservation cover air, water, soil and noise pollution, their effects on organisms, biodiversity loss, protected areas, sustainable resource use and methods for reducing environmental damage.
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