What is the process of converting wet waste into manure called?

Composting is the natural process of converting wet organic waste such as vegetable peels, leftover food, fruit scraps, and garden waste into manure or compost. This process uses the activity of microorganisms like bacteria and fungi, which break down the complex organic matter into simpler, nutrient-rich materials. The resulting product, called compost, is an excellent organic fertilizer that improves soil quality and promotes healthy plant growth.

Composting takes place under aerobic conditions, meaning in the presence of oxygen. The microorganisms feed on organic materials and release heat, carbon dioxide, and water vapor during decomposition. The process passes through several stages: the mesophilic phase (moderate temperature), thermophilic phase (high temperature), and maturation phase (cooling and stabilization). During these stages, organic compounds like proteins, fats, and carbohydrates are broken down into humus — a dark, nutrient-rich substance.

The main advantage of composting is that it recycles organic waste, reduces the amount of garbage sent to landfills, and returns valuable nutrients to the soil. It is one of the most sustainable methods of solid waste management because it mimics nature’s own recycling process. Unlike incineration, which burns waste and produces harmful gases, composting is an eco-friendly process that conserves energy and reduces pollution.

Metabolism refers to chemical reactions in living organisms, and conservation means saving resources — both unrelated to waste conversion. Thus, composting is the correct answer, as it specifically involves the biological decomposition of wet waste into manure. This concept is a key topic in Environmental Science and essential for understanding how humans can manage waste sustainably and protect natural ecosystems.