What is the main constituent in the following types of soil ?
(a) Blace soil
(b) Red soil

Explanation

To answer the question regarding the main constituents of black soil and red soil, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding Black Soil**:
- Black soil is primarily composed of clay particles.
- The presence of clay gives it a dark color, and it is rich in humus, which is beneficial for the growth of crops, especially cereals.

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