Getting Down and Dirty with Lumbricus terrestris

Soil Structure


How is the species Lumbricus terrsteris useful in its environment?  This question was briefly answered in the section Habitat, but will be explored more in depth in this section. Earthworms have also been useful to their ecosystes, and are even used by many farmers throughout histor, to provide optimum growing conditions for their crops. Earthworms play a huge role in the makeup of the soil around them. How do they affect this? Yasemin Kavdir, in the Book the Biology Of Earth Worms, 2011 explains , Earthworms are very importent contributers to the enviornment, by creating casts, burrows and digesting soil  (Kavidir 2011).  By digging around in the soil, consuming, and digesting the soil, and then excreting the soil, as well as making homes in the earth. This in turn can decide the makeup of the plant life in which the earth worm lives (Kavidir 2011).
Figure 2. Earth Worm Casting. Retrieved from signing up and downloading from Kuhn Photo.Retrieved on 2013/12/08

Earthworms can ingest soil and produce waste matter, known as a cast, which in turn creates aggregates in the soil. They can break down large aggregates into smaller one. After ingesting soil and plant matter the soil is compacted in the crop, or gut of the earthworm, and the egested or in simpler terms excreted. An aggregate is defined by Kavidir, 2011, as the following; “aggregates are formed through the combination of clay, silt, and sand with organic and inorganic substances” (Kavidir 2011).. By producing aggregates, the soil texture, properties, and ability to hold moisture takes a turn for the better. So by creating these the L. terrsteris, can “improve physical structure of the soil, increase drainage and aeration, enhance soil fertility, recycle nutrients, reduce run-off, supply better conditions for plant root growth”. Aggregates can also create strength and soil tension in the ground, and help to tabalize the soil make-up. Aggregates provide a premium hot spot for a plants roots to grow, because of its nutrient content, its ability for CO2 to reach the roots, and the ability for the surrounding area to contain just the right amount of water for the plant to uptake. Aggregates however are not the only reason the soil is made better by earth worms for the plants
(Kavidir 2011).

Earthworms move horizontally through the soil while feeding and creating burrows. By doing this, they make the soil useful for plant growth. While the particular species L. terrsteris does not make as many burrows as other species of earthworms, they continue to use the same burrows, their burrows are useful making the soil the way it is. Burrows allow the soil deeper down to contain macropores, which allow air and water to reachFigure 3. Earth Worm burrowing. Retrieved and downloaded from signing up for Kuhn Photo. Retrieved on 2013/12/08 these areas. This earthworm also brings decomposing matter to its burrows which also can increase the nutrient properties, like
polysaccharides, enzymes, and other plant nutrients of the soil (Kavidir 2011).

In conclusion Earthworms are very beneficial to their environments, especially the soil. They produce aggregates, casts and burrows, and provide hot spots for plant root growth. They break apart the soil and make large aggregates into to smaller compact ones, and create pores in the soil. All along with the pores created by aggregates, burrows can allow for soil aeration, or an easier passage of gasses though the soil. The earthworm activity can increase drainage and water flow in the soil, to provide the perfect of moisture for the roots of plants to take up. This species also increases the amount of sugars, enzymes and other plant nutrients, by ringing decaying matter to its burrow and by creating casts. Earthworms are useful to the farmer, the plant life, and in turn can provide for their entire ecosystems
(Kavidir 2011).


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Check out where we gathered our information from on our Reference page