Fill in the blanks :
In aquatic ecosystems, the limiting factor for the productivity is ..........

Answer

**Step-by-Step Solution:**

1. **Understand the Concept of Limiting Factors**: Begin by defining what limiting factors are. Limiting factors are conditions or resources that can restrict the growth, abundance, or distribution of an organism or a population within an ecosystem.

2. **Identify the Context**: The question specifically asks about aquatic ecosystems. In these ecosystems, various factors can influence productivity, which refers to the rate at which energy is produced through photosynthesis.

3. **Consider the Key Factors in Aquatic Ecosystems**: In aquatic ecosystems, the primary factors that can limit productivity include light, nutrients, and temperature. However, the ability of light to penetrate water is crucial for photosynthesis.

4. **Focus on Light as a Limiting Factor**: In aquatic environments, light availability decreases with depth. This means that only the upper layers of water receive sufficient light for photosynthesis, which is essential for the growth of aquatic plants and phytoplankton.

5. **Conclude with the Answer**: Based on the understanding that light is a critical factor that limits productivity in aquatic ecosystems, the blank can be filled with "light".

**Final Answer**: In aquatic ecosystems, the limiting factor for the productivity is **light**.

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