Small creaters

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Small Soil animals

In order to learn what is in the soil, one has to be able to physically see and be able to identify. This gets done most effectively by scientists testing areas of the soil that they've found interest in. Certain Soil Sampling Methods are used to collect each organism, some working better than others depending on what it is that one's trying to catch.

Sometimes it's best to take the visual approach when trying to learn about what's in the soil. Looking at a sample and feeling the soil in your hands can give great ideas as to the characteristics of the soil, Soil textures, and the Soil organisms. Although this might be the case, it's not the same for microfauna. There are so many customized niches in the soil that may cause one creature to be in one area and never be found anywhere else, due to soil heterogeneity that also challenges those preforming Root sampling methods.


Nematodes

Nematodes are a diverse part of the animal realm, inhabiting a ride range of habitats/environments. They have been found in almost every type of ecosystem out their, ranging from salt and fresh water, to soils from the polar regions straight down to the equator. Around an estimated 90 percent of nematodes species identified reside in the top 15 cm of the soil fauna. Unlike worms, they do not decompose organic matter, instead they are free living organisms. Nematodes that cause plant diseases to farmed crops have received a lot more attention then any of the others.How ever, most nematodes in the soil do not cause harm, in-fact most cause a beneficial help to the over all health of the soil and even to humans and our goals.


Impacts:The majority are of no harm or even have a beneficial use to us humans and our lives. Yet those that live in the soil and are plant eaters, find them selves in direct competition with us humans. With devastating consequences for them and us. They eat the plants, thereby hindering/harming the plants ability to perform basic functions like water or mineral uptake. When they begin to harm a farmers profit margins, which results in the use of chemical warfare being declared upon them. Killing them, along with more unknown species, along with poisoning our drinking water supply.

Bacterial-feeders: consume bacteria.

Fungal-feeders: feed by puncturing the cell wall of fungi and sucking out the internal contents.

Predatory nematodes: eat all types of nematodes and protozoa. They eat smaller organisms whole, or attach themselves to the cuticle of larger nematodes, scraping away until the prey’s internal body parts can be extracted.

Omnivores: eat a variety of organisms or may have a different diet at each life stage. Root-feeders are plant parasites, and thus are not free-living in the soil.

FUN FACT's Nematode were part of an ongoing research project conducted on the space shuttle Columbia, they were able to survive re-entry breakup back into and through the earths atmosphere.

They are one of natures ways of controlling the bacteria population of getting to out of hand.

Earthworms (oligochaeta)

"It may be doubted whether there are many other animals which have played so important a part in the history of the world, as have these lowly organised creatures."

(Charles Darwin)

Earthworms are know as ecosystem engineers, as their impact to the habitats they inhabit is huge. Without them a huge portion of dead litter would not be decomposed in a timely fashion or not at all. Along side bacteria and fungi, they are responsible for recycling nutrients and carbon back into the soil so plants and other organisms may use it again the next growing season or right away.

This occurs because the wonderful earth worms eat leaves, dung, dead animals and by doing so unlock nutrients like carbon, nitrogen and many more. These nutrients are then pooped out by the worms back into the soil, becoming an important building block and structure of the soil world.

Earth Worms can impact agriculture by increasing the productivity by 20-30%. This is further proven by the fact that in New Zealand once land was approved for agriculture, their native species disappeared leaving their soil earthworm free. Once non-native species were introduced productivity increased by 25-30%.


Soil Fauna: Classification

Five major groupings are widely accepted: classification based on body size; time spent in the soil; location or habitat in the soil profile; feeding strategies; and method of locomotion in the soil

body size::For those organisms that would be considered "small", we are interested in anything over the size of 2mm. How ever this method can be confusing, as different species of worms, for example, could be smaller then 2mm, while others are larger. Thus causing confusion sto which group that species should be put in. The size a animal can reach is not just dependent upon what species it is, but also in what kind of soil it lives in. Two members of the same species can differ in size just simply by being located in different part of a valley system, or being located in different temperate zones. This information can be used to also establish what kind of nutrients are in the soil, or are not in the soil. Can be used to compare two sites of soil to each other.


feeding habits: FeedingClassification.jpg

locomotion within the soil: Earth Worms can get around by using their bristles. Bristles are paired in groups on a segment of its body, they grab onto the burrow and push/slide it along. Using the bristles as a way to grab onto the side and lunge them selves forward.

Nematodes get around by contractions of their longitudinal muscles, this causes their body to flex and then move around by basically throbbing back and forth.

Reproductive Strategies: We can distinguish between organisms based on how they do the nasty. Examples of reproduction styles: Sexual/parthenogenesis/asexual. Or based on if they have a specific time from mating to just opportunists.

References

Nationwide, SARE. “Small and Medium-Size Soil Animals.” SARE: Sustainable Agriculture Research and Education, www.sare.org/Learning-Center/Books/Building-Soils-for-Better-Crops-3rd-Edition/Text-Version/The-Living-Soil/Small-and-Medium-Size-Soil-Animals.

Hendricks, David M. “5. Animals and Soil in Arizona.” Animals and Soil In, www.library.arizona.edu/exhibits/swetc/azso/body.1_div.5.html.

“Earthworms' Role in the Ecosystem.” Science Learning Hub, www.sciencelearn.org.nz/resources/9-earthworms-role-in-the-ecosystem.