You have learnt from the lessons in the earlier Modules that soil properties influence soil health'

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Soil Health Management
Virtual Academy for the Semi Arid Tropics
Module III

• You have learnt from the lessons in the
  earlier Modules that soil properties influence
  soil health.
• These soil properties in turn are affected by
  the agricultural practices followed by a farmer.
• Good agricultural practices not only help in
  managing the soil but also improve soil health.
• What are these good agricultural practices?

Course on Soil and Soil Health
2
Soil Health Management
Virtual Academy for the Semi Arid Tropics
Module III

• The good agricultural practices that help in
  improving and managing soil health focus on
• Improving and maintaining organic matter in
• the soil
• Avoiding tillage practices that harm the soil
  
• structure
• Conserving the soil from erosion and other soil
  
• degrading effects
• Adopting integrated nutrient and pest
• management practices,
• Rectifying soil problems like acidity and
  
• alkalinity.

Course on Soil and Soil Health
3

• After completing this Lesson, you will be able
  to answer
• What is soil degradation?
• What are the causes for soil degradation?
• What is soil erosion?
• How soil erosion occurs?
• List out the various practices that help in
  preventing soil erosion?
• Explain the practices that help in preventing
  soil erosion on soils with different slopes?

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• Soil degradation refers to changes in a soil
  from its original nature.
• Soil degradation results due to many
  agricultural activities.
• The visible soil degradation is due to soil
  erosion.
• The invisible soil degradation happens due to
  the loss of plant nutrients and many useful
  microorganisms (chemical degradation), damage due
  to water logging and soil compactness etc
  (physical degradation).

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• World-wide soil
  Degradation
• Source of Data Oldeman, L.R., R.T.A. Hakkeling,
  and W.G. Sombroek. 1990. World Map of the Status
  of Human-Induced Soil Degradation. An Explanatory
  Note, rev. 2nd edition. International Soil
  Reference and Information Center, Wageningen, the
  Netherlands.

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• Soil erosion results due to washing-off of the
  rich top soil from a field due to gravity of
  water from heavy rainfall or wind.

Soil erosion
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• Fortunately, there are many ways to reduce soil
  erosion through certain practices
• For areas with mild slopes
• Reduced tillage Tilling only the areas that
  matter while minimally disturbing the soil.
  Ex. Tilling between furrows.

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• Fortunately, there are many ways to reduce soil
  erosion through certain practices
• For areas with mild slopes
• Stubble-mulching Leaving crop stubble on
  the field as long as possible to keep the
  soil covered, reduce evaporation, reduce
  weed growth and allow the soil organisms
  to decompose the plant residues.

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• For areas with gentle slopes
• Contour bunding consist of building earthen
  embankments across the slope of the land,
  following the contour as closely as possible.

Contour bund
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• For areas with gentle slopes
• Contour bunding
• A series of such bunds divide the area into
  strips and act as barriers to the flow of water,
  thus reducing the amount and velocity of the
  runoff allowing better infiltration of water into
  the soil.

Contour bunds
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For areas with gentle slopes Vegetative
bunds Permanent contour strips of grass or
shrubs are useful on gentle slopes. Dense and
continuous vegetative cover will slow down the
runoff and cause deposition of silt which over
time act as a bench terrace.   Economically
important and unpalatable grasses like Vetiver
(Vetiveria zizanoides) and Cymbopogon citratus
are useful.
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• For areas with gentle slopes
• Contour cultivation is a practice of conducting
  field operations, such as ploughing, planting,
  and cultivating land, across the slope rather
  than up and downhill (Fig.).

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• For areas with gentle slopes
• Contour cultivation The ridges or broad-bed
  furrows (BBF) and the crop cover on the contoured
  rows hold water and thus prevent runoff and soil
  erosion.

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• For areas with gentle slopes
• Strip cropping
• Growing of crops in strips of few rows of each
  crop. A strip of tall growing cereal crop can be
  altered with a strip of short legume crop. This
  reduces the down slope length of the field
  considerably, reducing the chance of erosion.
  Neighboring strips uses leached nutrients.

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• For areas with gentle slopes
• Strip cropping

Soybean strip
Maize strip
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• For areas with steeper slopes
• Terracing
• The ultimate in soil conservation on steeper
  hills. It is extensively practiced in plantation
  crops and paddy cultivation in hills where water
  is also harvested at the same time. Terracing can
  reduce erosion many-fold.

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• For more information on soil and water
  conservation, please visit the following Internet
  sites.
• http//www.krishiworld.com/html/soil_water_con
  2.html
• http//megsoil.nic.in/why_cons.htm

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Soil Health Management
Virtual Academy for the Semi Arid Tropics
Module III

• This concludes the Lesson 3 Conserving the
  soil from degrading effects - in this Module.
• Next, Lesson 4 in this Module, practices for
  integrated nutrient and pest management are
  explained briefly.
• Problem soils and their reclamation procedures
  are discussed in the last Lesson in this Module.
• Select Lesson 4 in Module III from the list of
  course contents

Course on Soil and Soil Health