Step 1: Understanding the Concept:
In forest management, dry or moist deciduous forests may experience regeneration failures due to seed mortality, weed competition, or poor soil physical conditions.
To resolve this, foresters use localized artificial regeneration methods to assist natural recovery.
Step 2: Detailed Explanation:
Let us define the specific forestry term described in the question:
- Rab: In Indian forestry, a "Rab" is a localized patch (typically measuring around $20\text{ m} \times 20\text{ m}$) where logging slash, dry leaves, and branches are piled up and burned.
Burning the debris sterilizes the soil, kills weed seeds, and releases ash rich in nutrients like potassium.
The patch is then artificially regenerated by sowing seeds or planting seedlings of valuable tree species to supplement deficient natural regeneration.
Let us analyze why the other options are incorrect:
- Block: A large, permanent administrative division of a forest, containing many compartments.
- Compartment: A permanent administrative unit of a forest, typically bounded by natural features or roads, used for forest management.
- Coupe: An area of forest designated for harvesting or felling in a particular year.
Therefore, "Rab" is the correct term for the described regeneration patch.
Step 3: Final Answer:
The patch of $20\text{ m} \times 20\text{ m}$ burnt and artificially regenerated to supplement natural regeneration is called Rab.