Chapter 7 Flashcards
Process which lowers the
current or future capacity of
the soil to produce goods or
services
Soil degradation defined
are the weathering products
of rocks and minerals
Soil
❑ Caused by natural (due to soil
formation) or can be caused by
human activities such as:
a.
Continuous
application
of
ammonium sulfate
b.
Intensive cultivation without
addition of nutrients
c.
Draining coastal areas
Soil acidification
❑ Continuous removal of
nutrients without addition
in the form of fertilizer
Nutrient mining
❑ Removal of fertile organic matter
due to erosion exposes the
subsoil which is generally acidic
and less fertile.
❑ Caused by deforestation, burning
crop
residues,
conventional
tillage, and overgrazing
Loss of nutrient and organic matter
❑ Due to indiscriminate use
of
agro-chemicals
and
accumulation
of
toxic
heavy metals from the
industry,
mining
and
agricultural activities
Pollution
❑ Caused by long-term use of
farm
equipment
in
intensively cultivated lands
Pollution
❑ Due to indiscriminate use
of
agro-chemicals
and
accumulation
of
toxic
heavy metals from the
industry,
mining
and
agricultural activities and by overgrazing
Soil compaction
❑ human influenced erosion (e.g., over grazing,
deforestation, plowing hillside up & down)
Accelerated erosion
❑ Uniform
erosion
from the entire soil
surface
Sheet erosion
❑ Water concentrates in
small channel (rills) as
it runs off the soil
Rill erosion
❑ Advanced stage of rill
erosion
❑ Deep
channels
that
cannot
be erased
by
cultivation
Gully erosion
What are the different processes
of water erosion?
Detachment
Transportation
Deposition
runoff and sediments
are caught in a tray and
led through pipes to
collecting tanks which
retain all, or a fixed
proportion of the plot
output.
Erosion plots
• soil erosion is measured
by using isotope caesium-
137 (137 Cs).
tracers/radioisotopes
• small catchpits (receiving
reservoir) were dug at the
lower part of the slope to
catch eroded sediments
Catchpits
