An increase in carbondioxide content in the atmosphere would not cause

Options

A. more heat to be retained by the environment
B. increase in photosynthesis in plants
C. global warming
D. abundance of desert plants

Explanation

To solve the question regarding the effects of an increase in carbon dioxide content in the atmosphere, we can analyze the options provided and determine which one would not be a consequence of such an increase.

### Step-by-Step Solution:

1. **Understanding Carbon Dioxide's Role**:
- Carbon dioxide (CO2) is a greenhouse gas, which means it contributes to the greenhouse effect. This effect leads to the retention of heat in the Earth's atmosphere.

2. **Analyzing the Options**:
- **Option A**: More heat to be retained by the environment.
- This is true because an increase in CO2 leads to more heat being trapped in the atmosphere, contributing to global warming.

- **Option B**: Increase in photosynthesis in plants.
- This is also true. Plants use CO2 for photosynthesis, so an increase in CO2 can enhance the rate of photosynthesis, assuming other conditions (like water and light) are favorable.

- **Option C**: Air pollution and global warming.
- This is true as well. Increased CO2 levels contribute to air pollution and are a significant factor in global warming.

- **Option D**: Abundance of desert plants.
- This is the key option. While CO2 is necessary for plant growth, desert plants require other conditions such as adequate water, which is scarce in desert environments. Therefore, an increase in CO2 alone would not lead to an abundance of desert plants.

3. **Conclusion**:
- Based on the analysis, the correct answer is **Option D**: An increase in carbon dioxide content in the atmosphere would not cause an abundance of desert plants.

### Final Answer:
An increase in carbon dioxide content in the atmosphere would not cause the abundance of desert plants.

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