Ecosystem forest , Grassland , Estuaries , Pond Lake Wetland.
Amongst these which is smallest ecosystem ?

Explanation

To determine which among the listed ecosystems is the smallest, we can analyze each option step by step.

### Step-by-Step Solution:

1. **Identify the Ecosystems**: The ecosystems mentioned are forest, grassland, estuaries, pond, lake, and wetland.

2. **Analyze Forest and Grassland**:
- Forest ecosystems are large areas dominated by trees and various forms of wildlife.
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