At the simplest level, composting requires gathering a mix of green waste (nitrogen-rich materials such as leaves, grass, and food scraps) and brown waste (woody materials rich in carbon, such as stalks, paper, and wood chips). The materials break down into humus in a process taking months. Composting can be a multistep, closely monitored process with measured inputs of water, air, and carbon- and nitrogen-rich materials. The decomposition process is aided by shredding the plant matter, adding water, and ensuring proper aeration by regularly turning the mixture in a process using open piles or windrows. Fungi, earthworms, and other detritivores further break up the organic material. Aerobic bacteria and fungi manage the chemical process by converting the inputs into heat, carbon dioxide, and ammonium ions. thumb|Composter made from a hollow log Composting is an important part of waste management, since food and other compostable materials make up about 20% of waste in landfills, and due to anaerobic conditions, these materials take longer to biodegrade in the landfill. Composting offers an environmentally superior alternative to using organic material for landfill because composting reduces methane emissions due to anaerobic conditions, and provides economic and environmental co-benefits. For example, compost can also be used for land and stream reclamation, wetland construction, and landfill cover.
At the simplest level, composting requires gathering a mix of green waste (nitrogen-rich materials such as leaves, grass, and food scraps) and brown waste (woody materials rich in carbon, such as stalks, paper, and wood chips). The materials break down into humus in a process taking months. Composting can be a multistep, closely monitored process with measured inputs of water, air, and carbon- and nitrogen-rich materials. The decomposition process is aided by shredding the plant matter, adding water, and ensuring proper aeration by regularly turning the mixture in a process using open piles or windrows. Fungi, earthworms, and other detritivores further break up the organic material. Aerobic bacteria and fungi manage the chemical process by converting the inputs into heat, carbon dioxide, and ammonium ions. thumb|Composter made from a hollow log Composting is an important part of waste management since food and other compostable materials make up about 20% of waste in landfills, and due to anaerobic conditions, these materials take longer to biodegrade in the landfill. Composting offers an environmentally superior alternative to using organic material for landfill because composting reduces methane emissions due to anaerobic conditions, and provides economic and environmental co-benefits. For example, compost can also be used for land and stream reclamation, wetland construction and landfill cover.