Preparation and Preservation of Compost and Farmyard Manure

Organic manures are essential components of sustainable agriculture, providing necessary nutrients to the soil while improving its physical, chemical, and biological properties. Among the most widely used organic fertilizers are Farmyard Manure (FYM) and Compost.

Farmyard Manure (FYM)

Farmyard manure refers to the decomposed mixture of animal excreta (dung and urine) with litter and leftover material from roughages or fodder fed to the cattle. It is a complete fertilizer, providing primary nutrients like nitrogen, phosphorus, and potassium, along with essential micronutrients.

Preparation of FYM

The quality of FYM largely depends on the method of collection and storage. The recommended process follows these steps:

• Collection: Urine is rich in nitrogen and potassium; therefore, it should be absorbed by using bedding materials like straw, dried leaves, or sawdust in the cattle shed.
• Trench Method: Trenches of suitable dimensions (e.g., 68 meters long, 2 meters wide, and 1 meter deep) are dug. The mixture of dung, urine-soaked straw, and refuse is placed in the trench in layers.
• Filling: Once a layer reaches about 0.5 meters above ground level, it is plastered with a mixture of cow dung and soil to prevent nutrient loss through leaching and volatilization.
• Decomposition: The material is allowed to decompose for approximately 3 to 4 months before it is ready for field application.

Preservation Practices

To ensure high nutrient content, preservation is critical:

• Covering: Protect the manure pit from direct sunlight and heavy rainfall to prevent the loss of nitrogen and the leaching of soluble nutrients.
• Compaction: Proper compaction of the layers inside the trench minimizes aerobic decomposition, which helps in retaining nitrogen.
• Moisture Control: The pit should be kept moist but not waterlogged to facilitate the action of beneficial microorganisms.

Compost

Composting is the biological decomposition of organic waste materials such as crop residues, weeds, vegetable waste, and other plant debris by microorganisms under controlled conditions.

Preparation Methods

There are two primary methods for preparing compost on a farm scale:

• Pit Method: Similar to the FYM trench method, organic waste is collected and placed in layers. To accelerate the process, thin layers of dung slurry or wood ash can be added to provide a microbial inoculant.
• Heap Method: Used where pits are not feasible. Waste is piled up into heaps about 1-1.5 meters high. The heap is turned periodically to ensure aeration, which speeds up the decomposition process significantly.

Steps for Quality Composting

1. Collection: Gather all farm and kitchen waste, ensuring a balance between "green" material (nitrogen-rich, like fresh leaves) and "brown" material (carbon-rich, like dry stalks).
2. Layering: Arrange the waste in thin layers, sprinkling water to maintain moisture.
3. Turning: If using the heap method, turn the pile every 34 weeks to distribute moisture and oxygen.
4. Maturity: The process is complete when the material turns into a dark, crumbly, earthy-smelling substance. This usually takes 3 to 6 months depending on the climate.

Common Principles for Preservation

The goal in both FYM and compost management is to prevent the loss of nitrogen, which often escapes into the atmosphere as ammonia. To preserve these manures effectively:

• Avoid exposure: Never keep manure in small, loose heaps, as this exposes a large surface area to the air, promoting rapid loss of nitrogen.
• Incorporate into soil: Once the manure is mature, it should be applied to the soil and incorporated immediately rather than leaving it on the surface where sunlight can degrade its nutrient quality.
• Additives: Adding small amounts of superphosphate to the manure pit can help fix ammonia and improve the phosphorus content of the final product.

By following these systematic approaches to preparation and preservation, farmers can convert low-value waste into high-value soil amendments, ultimately reducing the dependency on chemical fertilizers and fostering a healthier agro-ecosystem.