From page 15
It should be noted that
considerably less carbon
sequestration takes place in
winter, and least on the
highveld, because of the
number of plant species that
die back due to cold and frost
and thus lose the green
chlorophyll in their leaves that
is necessery for photosynthesis
to occur.
The primary way that carbon
is stored in the soil is as soil
organic matter (SOM). SOM is
a complex mixture of carbon
compounds, consisting of
decomposing plant and
animal tissue, microbes
(protozoa, nematodes, fungi
and bacteria) and carbon
associated with soil minerals.
Carbon can remain stored in
soils for millennia, or be
quickly released back into the
atmosphere. Climatic
conditions, natural vegetation,
soil texture, and drainage all
affect the amount and length
of time carbon is stored.
CO2 EMISSION
Land management practices can do a lot
to help the process of carbon sequestration
How we manage livestock,
and how we manage the
pastures those livestock graze
on, plays a significant role in
atmospheric carbon pollution.
Terrestrial or biological
sequestration means using
plants to capture CO2 from
the atmosphere and then
storing it as carbon in the
stems and roots of the plants
as well as in the soil. Terrestrial
sequestration is a set of land
management practices that
maximizes the amount of
carbon that remains stored in
the soil and plant material for
the long term.
No-till farming, wetland
management, rangeland
management, and reforestation are examples of terrestrial
sequestration practices that
are already in use.
Removing CO2 from the
atmosphere is only one
significant benefit of
enhanced carbon storage in
soils. Improved soil and water
quality, decreased nutrient
loss, reduced soil erosion,
increased water conservation
and greater crop production
may result from increasing the
amount of carbon stored in
agricultural soils.
Management techniques,
which are successful in
providing a net carbon sink in
soils, include the following:
K Conservation tillage
minimises or eliminates
manipulation of the soil for
crop production, although
some scientists have yet to be
convinced that the method
increases carbon storage. It
includes the practice of mulch
tillage, which leaves crop
residues on the soil surface.
These procedures generally
reduce soil erosion, improve
water use efficiency, and
increase carbons concentra-
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tions in the topsoil.
Conservation tillage can also
reduce the amount of fossil
fuel consumed by agricultural
operations. It has been
estimated by some landowners to have the potential to
sequester a significant amount
of CO2.
K Cover cropping is the use
of crops such as legumes and
grasses for protection and soil
improvement between
periods of regular crop
production. If the cover crop
is incorporated into the soil
Continued on page 20