Which one of the following soil conservation measures is most effective in preventing the formation of gullies?

Correct Option

The correct option is

Rock Dam

Explanation

Gully erosion occurs when running water cuts deep channels through the soil, often rendering land unfit for cultivation (creating badland topography). Conservation measures to address this are typically mechanical or structural interventions designed to check the velocity of concentrated water flow.

Option Analysis:

• Mulching: This involves covering the bare ground between plants with a layer of organic matter like straw. While it helps retain soil moisture and prevents rain splash (sheet) erosion, it is not a structural barrier capable of stopping the high-velocity water flow found in gullies.
• Rock Dam Rock Dam: Correct. Rocks are piled up across drainage channels or gullies to slow down the flow of water. This reduces the kinetic energy of the runoff, prevents the gully from deepening or widening, and allows sediment to settle. It is a specific mechanical measure for gully plugging.
• Intercropping: This is the practice of growing different crops in alternate rows. It protects the soil from rain wash and helps maintain fertility, but it is an agronomic measure intended for general field protection rather than a structural solution for established gullies.
• Shelter Belts Shelter Belts: These are rows of trees planted to check wind movement. They are primarily effective against wind erosion in coastal and dry regions and do not address water-induced gully erosion.

Key Takeaway:
Rock dams are mechanical barriers specifically constructed across gullies to reduce water velocity and prevent further soil loss, whereas shelter belts target wind erosion and mulching targets moisture retention.