Increasing amount of chemical fertilizers leads to

Options

A. eutrophication
B. biomagnification
C. dechlorification
D. 1 and 2

Answer

### Step-by-Step Solution

1. **Understanding Chemical Fertilizers**: Chemical fertilizers are substances that provide essential nutrients to plants, primarily nitrogen, phosphorus, and potassium. When used in excess, they can lead to environmental issues.

2. **Identifying the Effects of Excess Fertilizers**: The question asks about the consequences of increasing amounts of chemical fertilizers. The primary environmental concerns associated with this are eutrophication, biomagnification, and dechlorification.

3. **Explaining Eutrophication**: Eutrophication is the process where water bodies, such as lakes, become enriched with nutrients (mainly nitrogen and phosphorus) from fertilizers. This nutrient enrichment leads to excessive growth of algae, known as algal blooms.

4. **Consequences of Eutrophication**: As algae grow rapidly, they can deplete oxygen in the water when they die and decompose, leading to hypoxic conditions (low oxygen levels). This can harm aquatic life, resulting in fish kills and loss of biodiversity.

5. **Examining Other Options**:
- **Biomagnification**: This refers to the increasing concentration of toxic substances (like mercury or DDT) in the food chain as one moves up trophic levels. While it is a significant environmental issue, it is not directly caused by the use of chemical fertilizers.
- **Dechlorification**: This is a process used to remove chlorine from water, typically in water treatment. It is not related to the effects of chemical fertilizers.

6. **Conclusion**: The primary effect of increasing amounts of chemical fertilizers is eutrophication. Therefore, the correct answer to the question is that increasing amounts of chemical fertilizers lead to eutrophication.

### Final Answer
Increasing amounts of chemical fertilizers lead to **eutrophication**.

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