Benthic organism are affected most by

Options

A. Surface turbulance of water
B. Sediment characteristics
C. Water holding capacity of soil
D. Light reaching the forest floor.

Answer

**Step-by-Step Solution:**

1. **Understanding Benthic Organisms**: Benthic organisms are those that live at the bottom of aquatic environments, such as oceans, rivers, and lakes. They are adapted to life in these specific conditions.

2. **Identifying Environmental Factors**: Consider the environmental factors that affect organisms living at the bottom of water bodies. Key factors include light availability, water movement, and sediment characteristics.

3. **Analyzing Light Availability**: At the bottom of water bodies, light penetration is minimal or non-existent. This means that photosynthesis is not a factor for benthic organisms, as they do not rely on light for energy.

4. **Considering Water Movement**: The turbulence of water affects organisms in the upper layers more than those at the bottom. Benthic organisms are less influenced by surface turbulence since they are anchored or settled on the substrate.

5. **Focusing on Sediment Characteristics**: The most significant factor affecting benthic organisms is the type of sediment or soil at the bottom of the water body. The composition, texture, and nutrient availability of the sediment directly influence the types of organisms that can thrive there.

6. **Role of Decomposers**: The bottom of the water body is often rich in decomposers that break down organic matter. This decomposition process is crucial for nutrient cycling and affects the overall ecosystem at the benthic level.

7. **Conclusion**: Based on the analysis, the factor that affects benthic organisms the most is the sediment characteristics at the bottom of the water body.

**Final Answer**: Benthic organisms are affected most by sediment characteristics.

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