Which of the following statements is correct?
- Biomagnification refers to increase in concentration of the toxicant at successive trophic levels.
- Presence of large amount of nutrients in water restricts ‘Algal Bloom’
- Algal Bloom decreases fish mortality
- Eutrophication refers to increase in domestic sewage and waste water in lakes.
The Correct Option is A
Solution and Explanation
A is correct - Biomagnification is the process through which certain substances, such as toxins or pollutants, become more concentrated as they move up the food chain. This results in higher concentrations of these substances in organisms at higher trophic levels.
B is incorrect - Presence of a large amount of nutrients in water, often caused by excessive nutrient runoff, can actually promote algal bloom, not restrict it.
C is incorrect - Algal blooms can lead to fish mortality due to a decrease in oxygen levels as the algae die and decompose. This process can create "dead zones" in water bodies.
D is incorrect - Eutrophication refers to the excessive nutrient enrichment of water bodies, often from sources like agricultural runoff or sewage, leading to increased plant growth (algae and other aquatic plants). This excessive growth can disrupt the balance of the ecosystem and lead to issues like oxygen depletion.
So, the correct option is (A): Biomagnification refers to increase in concentration of the toxicant at successive trophic levels.
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Concepts Used:
Water Pollution
- Water pollution means the contamination of water bodies such as seas, lakes, rivers, aquifers, oceans, and groundwater caused majorly due to inhuman activities with industrial and agricultural effluents. It is the change of chemical, biological, or physical properties of water that will result in a destructive consequence for living organisms.
- Portable water is considered safe for human and animal consumption as well as used for drinking, cooking, crop irrigation, washing, etc,. Nowadays, chemicals, bacteria, and other pollutants are also influencing this. It adversely acts on all the living forms, directly or indirectly depending upon the source. The effects of water pollution can be felt for years to come.
Sources of Water Pollution:
The following are the major sources of Water Pollution:
- Domestic Waste
- Urbanization
- Deforestation
- Industrial effluents
- Social and Religious Practices
- Insecticides and pesticides
- Detergents and Fertilizers