Which of the following is not true for decomposition?

Options

A. The rate of decomposition is controlled by chemical composition of detritus and climatic factors
B. Decomposition rate si slower if detritus is rich in lignin and chitin
C. Decomposition rate is quicker if detritus is rich in nitrogen and sugars
D. Optimum temperature and aerobiasis inhibit decomposition

Answer

To determine which statement is not true for decomposition, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Decomposition**:
- Decomposition is the process where complex organic matter is broken down into simpler inorganic substances, such as carbon dioxide, water, and nutrients. This process is essential for nutrient cycling in ecosystems.

2. **Identify Decomposers**:
- The organisms that facilitate decomposition are known as decomposers, which primarily include bacteria and fungi. They play a crucial role in breaking down dead organic matter.

3. **Evaluate the Statements**:
- We need to analyze the given statements about decomposition to identify which one is incorrect.

4. **Check the First Statement**:
- The rate of decomposition is influenced by the chemical composition of detritus and climatic factors. This statement is true as the presence of certain substances can speed up or slow down the decomposition process.

5. **Check the Second Statement**:
- It states that decomposition is slower if detritus is rich in lignin and chitin. This is also true, as lignin and chitin are complex substances that decompose at a slower rate.

6. **Check the Third Statement**:
- The statement about optimum temperature and aerobiosis inhibiting decomposition needs careful consideration. Decomposition requires oxygen (aerobiosis) and is generally enhanced by optimum temperature and moisture levels. Therefore, this statement is false.

7. **Conclusion**:
- The statement that "optimum temperature and aerobiosis inhibit decomposition" is not true. Instead, these factors actually promote the decomposition process.

### Final Answer:
The statement that is not true for decomposition is: "Optimum temperature and aerobiosis inhibit decomposition."

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