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2.3 Biological Characteristics
2.3 Biological Characteristics
After completing this section
you will be able to:
•
Describe how plants cycle carbon,
including feeding the soil food web
•
Describe the key roles that microbes
play in facilitating soil processes
•
Describe some roles invertebrates and
vertebrates play in the soil food web
and in other soil functions
Almost all of life’s energy ultimately comes
from the sun through photosynthesis that
occurs in plant leaves. That means that
aboveground and belowground processes
are inherently connected. The soil food web
is critical for sustaining biological activity,
diversity, and productivity. The interactions
among plants, microbes, and animals are
key to functions such as regulating the flow
of water and storing and cycling nutrients
and other soil components. In this unit,
we discuss the life forms that make up soil
ecosystems and their beneficial, predatory,
and competitive interactions—holding in mind
that there is great variation in soil biological
characteristics in space and over time.
Arrows point in the
directions that energy and
nutrients are moving.
For example, livestock eat
plants; manure becomes
organic matter.
Learning Outcomes