According Robert Constanza, `50%` of the total cost for ecosystem services goes to:

Options

A. soil formation
B. nutrient cycling
C. recreation
D. climate regulation

Answer

To solve the question regarding Robert Costanza's findings on ecosystem services, we can break down the information step by step:

### Step-by-Step Solution:

1. **Understanding Ecosystem Services**: Ecosystem services are the benefits humans receive from nature, which include services like soil formation, nutrient cycling, climate regulation, and recreation.

2. **Robert Costanza's Research**: Robert Costanza and his colleagues conducted research to estimate the economic value of these ecosystem services. They calculated that the total value of ecosystem services is approximately $33 trillion per year.

3. **Distribution of Costs**: According to Costanza's findings, a significant portion of this total cost is attributed to specific services. In particular, he noted that soil formation accounts for a substantial percentage of the total cost.

4. **Identifying the Percentage**: The research indicates that 50% of the total cost for ecosystem services is attributed to soil formation. This means that out of the $33 trillion, about $16.5 trillion is linked to soil formation.

5. **Conclusion**: Therefore, the correct answer to the question is that 50% of the total cost for ecosystem services goes to soil formation.

### Final Answer:
**Soil Formation**

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