A rabbit feeds on grass and gains 1 kg weight within two months this rate of biomass gain in termed as_________.

Answer

To solve the question, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Identify the Organism and Its Diet**: The question states that a rabbit feeds on grass. Here, the rabbit is a consumer (heterotroph) that relies on producers (plants) for its energy and nutrients.

2. **Understand Biomass Gain**: The rabbit gains 1 kg of weight over two months. This weight gain indicates an increase in biomass, which is the total mass of living matter in an organism.

3. **Define the Type of Production**: Since the rabbit is a consumer that derives its energy from a producer (grass), the process of biomass gain in this context is referred to as secondary production.

4. **Clarify the Term**: Secondary production specifically refers to the generation of biomass by heterotrophic organisms (like the rabbit) at the second trophic level of the food chain.

5. **Determine the Rate of Biomass Gain**: The question emphasizes the rate of biomass gain over a specific time period (2 months). This rate is termed secondary productivity.

6. **Final Answer**: Therefore, the rate of biomass gain of the rabbit, which is 1 kg within two months, is termed as **secondary productivity**.

### Final Answer:
The rate of biomass gain in this context is termed as **secondary productivity**.

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