Wednesday, September 8, 2010

Microorganisms In Soil

Garden soil is literally teeming with microorganisms.


"Microorganisms such as bacteria, fungi...and protozoa are all vital to the reduction of organic and mineral wastes into plant nutrients," reports Garden-Soil.com. In other words, soil would not be of any use to your plants without them. Garden soil is literally teeming with microorganisms, though each owns a very brief lifespan.


Bacteria


Bacteria in soil cannot be detected with the naked eye.


According to the University of Western Australia, most soil bacteria are only one micron long or wide, though a few are larger. Most are single-cell microorganisms. Soil bacteria is responsible for such actions as breaking down organic material, keeping levels of disease down and transforming nutrients within a plant's roots. One of the most important functions of soil bacteria is converting nitrogen into a form that plants can use. Azobacter is a genus that turns nitrogen in the atmosphere into ammonium, which plants can absorb. Bacteria need water to do their work. Moreover, as most bacteria cannot move on their own, they rely on the movement of water to disperse through soil.


Fungi


Fungi are cells that tend to grow in threads or strands just a few micrometers in diameter. These strands inveigle their way into the spaces between soil particles, plant roots and rocks. Like bacteria, fungi help digest organic material into nutrient matter that plants can use. In addition, they help stabilize soil aggregates by binding together soil particles, which helps with water permeability and moisture absorption capability. More specifically, certain groups of fungi make phosphorus soluble and convey such nutrients as phosphorus and nitrogen to plants. Some of these fungi grow on the surface of plant roots while others actually live inside plant root cells. Fungi need air to live. They will have a hard time surviving in soil that is compacted or waterlogged.


Protozoa


Single-cell protozoa feed on bacteria, as well as organic matter, fungi and even other protozoa. According to the USDA, they are 5 to 500 micrometers in size, making them much larger than bacteria. Protozoa produce nitrogen (in the form of ammonium) that plants can use during the process of eating. Unlike bacteria, protozoa are mobile. Among types of protozoa are ciliates, which propel themselves via hair-like material called cilia; amoebae, which use a temporary foot to move; and flagellates, which use flagella to pull themselves along. Protozoa, by eating bacteria, help regulate its numbers. They also help to keep diseases in check by feeding on pathogens. As with bacteria, moisture levels are critical to protozoan activity.

Tags: plant roots, that plants, bacteria fungi, Garden soil, Garden soil literally, literally teeming