Which is not an effect of acidic rain in a pond

Options

A. Increased fungal growth
B. Decreased insect population
C. Increased growth of green algae
D. `NO_(3) and SO_(4)` saturation.

Answer

To determine which option is not an effect of acidic rain in a pond, we can analyze each option based on the effects of acidic rain on aquatic ecosystems.

### Step-by-Step Solution:

1. **Understand Acid Rain**: Acid rain is precipitation that contains acidic components, primarily sulfuric acid and nitric acid, leading to a lower pH (typically around 4.0). This can have various effects on aquatic environments.

2. **Evaluate Each Option**:
- **Option 1: Increased Fungal Growth**: Acidic conditions can promote fungal growth, as fungi can thrive in a pH range of 4.0 to 9.0. Thus, this is a possible effect of acidic rain.
- **Option 2: Decreased Insect Population**: Acidic conditions can harm aquatic insects, leading to a decrease in their population. This is also a valid effect of acidic rain.
- **Option 3: Increased Growth of Green Algae**: Green algae typically prefer neutral to slightly alkaline conditions (pH around 6-8). Acidic conditions (pH 4.0) are not conducive to the growth of green algae. Therefore, this option is likely not an effect of acidic rain.
- **Option 4: NO3 and SO4 Saturation**: Acid rain contributes to the saturation of nitrates (NO3) and sulfates (SO4) in the water, which is a recognized effect of acidic rain.

3. **Conclusion**: Based on the analysis, the option that is not an effect of acidic rain in a pond is **Option 3: Increased growth of green algae**.

### Final Answer:
The correct answer is **Option 3: Increased growth of green algae**.

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