Which of the following methods of cultivation causes salinisation of soil?

Options

A. Transplantation
B. Crop rotation
C. Excessive irrigation
D. Broadcasting

Explanation

To determine which method of cultivation causes salinisation of soil, we can analyze the options provided and understand the concept of salinisation.

### Step-by-Step Solution:

1. **Understand Salinisation**:
- Salinisation is the process where a large amount of water accumulates in the soil, leading to an increase in salt concentration. This can make it difficult for plants to survive due to poor soil aeration and high salinity.

2. **Evaluate the Methods**:
- **Transplantation**: This method involves growing plants in nurseries and then transferring them to the field. It does not directly contribute to salinisation.
- **Crop Rotation**: This practice involves alternating different crops in a field across seasons. It helps improve soil quality and does not cause salinisation.
- **Excessive Irrigation**: This method involves applying more water than necessary to the soil. When too much water is added, it can lead to waterlogging and increased salt concentration in the soil, causing salinisation.
- **Broadcasting**: This is a method of sowing seeds by scattering them over the field. It does not directly affect soil salinity.

3. **Identify the Correct Method**:
- Among the methods evaluated, **Excessive Irrigation** is the one that causes salinisation of soil due to the accumulation of water and salts.

### Conclusion:
The method of cultivation that causes salinisation of soil is **Excessive Irrigation**.

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