Nuisance growth of aquatic plants and bloom-forming algae in natural waters is generally due to high concentrations of

Options

A. carbon
B. sulphur
C. calcium
D. phosphorus

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the cause of nuisance growth of aquatic plants and bloom-forming algae in natural waters. This phenomenon is often referred to as algal bloom.

2. **Identifying Key Nutrients**: Algal blooms are typically stimulated by the presence of certain nutrients in the water. The most common nutrients that contribute to this growth are nitrogen and phosphorus.

3. **Role of Nutrients**: When nitrogen and phosphorus are present in high concentrations in water bodies, they act as fertilizers for algae. This leads to rapid growth or proliferation of algae, resulting in an algal bloom.

4. **Consequences of Algal Bloom**: As the algae grow excessively, they consume a significant amount of dissolved oxygen in the water. This depletion of oxygen can lead to hypoxic conditions, which are detrimental to aquatic life, causing fish and other organisms to die.

5. **Long-term Effects**: Over time, the accumulation of dead algae and other organic matter can lead to the aging of the water body, a process known as eutrophication. This can eventually result in the lake or pond becoming a marsh or dry land.

6. **Conclusion**: Therefore, the high concentrations of nitrogen and phosphorus are primarily responsible for the nuisance growth of aquatic plants and bloom-forming algae in natural waters.

**Final Answer**: The high concentrations of nitrogen and phosphorus lead to the nuisance growth of aquatic plants and bloom-forming algae in natural waters.

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