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2. Soil Fundamentals
The semi-arid Southwest is habitat for ground squirrels, gophers, prairie
dogs, and moles, all of which live in soil. Through their burrowing activities,
these animals mix soil horizons and redistribute seeds and plant parts
throughout the soil. This mixing is on a scale that impacts soil, but not in
a detrimental way. Rather it introduces some diversity into the physical,
chemical, and biological aspects of the soil ecosystem.
Burrowing creatures
Vertebrates
Glossary
Bioturbation
The action of burrowing creatures as they
excavate tunnels and living areas in soil,
mixing soil layers
Livestock
Different livestock species have a variety of different eating and movement
abilities and preferences, and therefore they have a variety of interactions
with soil ecosystems. For example, when grazing is static the weight of
larger animals can cause soil compaction. Livestock can affect chemical and
biological characteristics by introducing nutrients and microbes through
their dung and urine that can help feed soil food webs, although unless
grazing management is employed, this effect is highly localized and often
concentrated in areas around water or shade. By trampling the soil surface,
they can deposit litter that protects and feeds soil.
The ways in which livestock eat affect the biological characteristics of soil by
impacting plant communities in a variety of ways. Stocking rate and climate
will affect how livestock affect soils. Here we provide a brief overview of ways
the main livestock animals get their food and the effects they may have on
soils, noting that different varieties (breeds) of each may have very different
behaviors, which can cause their impacts to vary.