The single plant nutrient mainly responsible for eutrophication is ________.

Answer

To solve the question regarding the single plant nutrient mainly responsible for eutrophication, we can follow these steps:

### Step 1: Understand Eutrophication
Eutrophication is the process where water bodies become enriched with nutrients, leading to excessive growth of algae and other unwanted plants. This can result in a decrease in oxygen levels in the water, harming aquatic life.

**Hint:** Eutrophication is linked to nutrient enrichment in water bodies.

### Step 2: Identify Key Nutrients
The primary nutrients that contribute to eutrophication are nitrogen and phosphorus. These nutrients often come from agricultural fertilizers and household waste.

**Hint:** Think about where nutrients in water bodies come from, such as fertilizers and waste.

### Step 3: Focus on the Question
The question asks for a single plant nutrient that is mainly responsible for eutrophication. While both nitrogen and phosphorus are important, the question specifies to choose one.

**Hint:** Consider which nutrient is more commonly associated with the problem of eutrophication.

### Step 4: Choose the Answer
Based on the information, nitrogen is often highlighted as a significant contributor to eutrophication, particularly due to its prevalence in fertilizers used in agriculture.

**Final Answer:** The single plant nutrient mainly responsible for eutrophication is **Nitrogen**.

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