How many of the following statements are incorrect ?
(i) Decomposition is largely an anaerobic process .
(ii) Fragmentation , leaching , and catabolism occur simultaneously on detritus.
(iii) The vertical distribution of different species occupying different levels is called stratification .
(iv) The pond is a deep water body .
(v) The rate of decomposition is controlled by the chemical composition of detritus and climatic factors.

Options

A. 1
B. 2
C. 3
D. 4

Answer

To determine how many of the given statements are incorrect, let's evaluate each statement one by one:

1. **Statement (i): Decomposition is largely an anaerobic process.**
- **Evaluation:** This statement is incorrect. Decomposition can occur in both aerobic (with oxygen) and anaerobic (without oxygen) conditions, but it is largely an aerobic process. Aerobic decomposition is generally faster than anaerobic decomposition.

2. **Statement (ii): Fragmentation, leaching, and catabolism occur simultaneously on detritus.**
- **Evaluation:** This statement is also incorrect. While fragmentation, leaching, and catabolism are all processes that occur during decomposition, they do not happen simultaneously. Fragmentation occurs first, followed by leaching, and then catabolism.

3. **Statement (iii): The vertical distribution of different species occupying different levels is called stratification.**
- **Evaluation:** This statement is correct. Stratification refers to the layering of different species in an ecosystem, such as trees at the top, shrubs in the middle, and herbs at the bottom.

4. **Statement (iv): The pond is a deep water body.**
- **Evaluation:** This statement is incorrect. A pond is typically classified as a shallow water body, allowing sunlight to penetrate to the bottom.

5. **Statement (v): The rate of decomposition is controlled by the chemical composition of detritus and climatic factors.**
- **Evaluation:** This statement is correct. The rate of decomposition is indeed influenced by the chemical composition of the detritus (e.g., presence of lignin or chitin) and climatic factors (e.g., temperature and moisture).

Now, let's summarize the evaluations:
- Incorrect statements: (i), (ii), and (iv)
- Correct statements: (iii) and (v)

**Total incorrect statements:** 3

**Final Answer:** 3 statements are incorrect.