Decomposition

Soil Matters

One tablespoon of soil has more organisms in it than there are people on Earth. Soil is a mixture of broken- down rocks, decaying organic matter, and other materials that plants use to grow. It is home to thousands of kinds of bacteria, as well as different kinds of earthworms and fungi.

Soil is made up of 50 percent air and water, 45 percent minerals, and 5 percent organic matter. Organic is anything that is living or was once living. This includes fallen leaves and animal remains. Inorganic is anything that is not living and never was living. Air, water, rocks, and minerals are all kinds of inorganic matter.

Soil helps the environment in many ways. It connects to the water cycle because it absorbs some precipitation and affects where rain, snow melt, and surface runoff go. It also filters pollutants because minerals and microbes in soil remove toxins from the environment. Finally, soil cycles nutrients such as carbon, nitrogen, and phosphorus through it. Plants use those nutrients to grow.

Decomposers Cycle Nutrients

Nutrients are part of the soil because of decomposition. Decomposition is the breakdown of organic waste materials into usable nutrients. The nutrients released by decomposers are essential for plant growth. Because of this, earthworms have been called “nature’s gardeners” because of their role in producing healthy soil.

As decomposers feed on organic matter, they break down the once-living matter. This causes the nutrients within the decomposing matter to be recycled back into the environment. The water stored in the once- living matter is also released back into the environment.

Composting

Decomposition is essential for plant growth because it returns nutrients to the soil. Because of this, many people use their scientific knowledge about decomposers to design containers that compost organic matter. These containers are called composters. Compost is organic matter that has decomposed and is used as a soil fertilizer. Fertilizer is any kind of matter that is applied to soils or plant structures (often leaves) to supply one or more kinds of plant nutrient. Composting is done by decomposers, primarily microbes. They need four ingredients to work effectively: carbon, nitrogen, oxygen, and water.

Almost all plants and animals contain both carbon and nitrogen. However, different organisms have different amounts of each. For example, matter that has a lot of carbon is often brown and dry. Matter that has a lot of nitrogen tends to be colorful and wet. Fruits and vegetables have a lot of nitrogen in them.

There are many factors that influence how soil forms and how rich in nutrients it is. For example, a dry environment may have a lot of inorganic matter, such as gravel or sand. In contrast, an environment with many trees, like a forest, will have more decaying organic matter.

Weather and climate also affect how many nutrients a particular soil holds. In climates that are wet and warm, decomposition occurs more quickly. This causes more nutrients to be available to growing plants. Dry and cool climates have soils with fewer nutrients, and therefore less plant life. This is because microbes do best in warm temperatures, between 21 and 38 degrees Celsius (70 and 100 degrees Fahrenheit). Populations of microbes double in the soil with every increase of 12 degrees.

The amount of oxygen also influences soil quality. Like all organisms, decomposers need oxygen to survive. That oxygen comes from the air. Because of this, soil that is looser allows oxygen to reach deep into it. This results in decomposition that occurs more quickly. Soils that are tightly packed together, such as soils with clay, have less decomposition because there is less oxygen.

The amount of water also influences how much decomposition happens. All living things, including microbes, need water to survive. However, too much water fills the spaces in the soil, blocking oxygen. Because of this, decomposition happens most quickly in soils that are sometimes wet and sometimes dry.