Which of the following is expected to have the highest value `(gm//m^(2)//yr)` in a grassland ecosystem?

Options

A. Gross Production (GP)
B. Net Production (NP)
C. Secondary Production
D. Teritary Production

Answer

To determine which factor has the highest value in a grassland ecosystem measured in grams per square meter per year (gm/m²/yr), we need to analyze the different types of productivity within the ecosystem. Here’s a step-by-step breakdown of the solution:

### Step 1: Understand the Types of Productivity
In an ecosystem, productivity can be categorized into several types:
- **Gross Primary Productivity (GPP)**: This is the total amount of energy captured by photosynthetic organisms (like plants) in a given area over a certain time period.
- **Net Primary Productivity (NPP)**: This is the amount of energy that remains after accounting for the energy lost through respiration by the producers. It is calculated as GPP minus the energy used in respiration.
- **Secondary Production**: This refers to the generation of biomass by heterotrophic organisms (consumers) that consume the primary producers.
- **Tertiary Production**: This involves the production of biomass by higher-level consumers.

### Step 2: Identify the Highest Value
Among these types of productivity, Gross Primary Productivity (GPP) is expected to have the highest value in a grassland ecosystem. This is because GPP represents the total energy captured by plants, which is generally greater than the energy available after respiration (NPP) or the energy produced by consumers (secondary and tertiary production).

### Step 3: Conclusion
Therefore, the answer to the question is:
**Gross Primary Production (GPP)** is expected to have the highest value in a grassland ecosystem, measured in grams per square meter per year (gm/m²/yr).

### Final Answer
The correct answer is **Gross Production**.

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