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
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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
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• After completing this Lesson, you will be able
  to answer
• 1. What are the practices that improve soil
• organic matter?
• 2. What type of organic manures are available
• for improving soil organic
  matter?
• 3. How farm yard manure or compost applied
• to a soil?
• 4. How green manuring is practiced?
• 5. What are the crops used for green
• manuring?
• 6. How green manuring helps in improving soil
• health?

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• After completing this Lesson, you will be able
  to answer
• 7. What is green leaf manuring?
• 8. Which are the popular plants/trees used for
• green leaf manuring?
• 9. What is a cover crop?
• 10. Name some useful cover crops?
• 11. How cover crops help in improving soil
  health?
• 12. What is crop rotation?
• 13. How proper crop rotation helps in
  improving
• soil health?
• 14. How do you select a suitable crop
  rotation for
• your farm?

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• The organic matter in the soil can be
  improved by the following practices
• Use of organic manures
• Adding off-field organic material
• Growing of cover crops
• Adopting suitable crop rotation

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• A. Use of organic manures
• Organic manures are natural products used to
  provide food (plant nutrients) for the crop
  plants.
• Organic manures applied in good quantities
  increase the organic matter in the soil.
• Organic matter in turn releases the plant food
  into available forms for use by crops.

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• A. Use of organic manures
• However, organic manures should not be seen only
  as carriers of plant food.
• These manures also enable a soil to hold more
  water and also help to improve drainage in clay
  soils.
• They provide organic acids that help to dissolve
  soil nutrients and make them available for the
  plants.

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• A. Use of organic manures
• There are a number of organic manures like
• Farmyard manure,
• Compost prepared from crop residues and
  other farm wastes,
• Vermicompost,
• Oil cakes, and
• Biological wastes animal bones, slaughter
  house refuse etc.

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• A. Use of organic manures
• Compost
  Vermicompost

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• A. Use of organic manures
• One can apply as much quantity as possible even
  though the availability of these material is
  limited in a farm. Excess application of organic
  manures do not harm the soil unlike fertilizers.
• These organic manures are applied 2 to 3 weeks
  ahead of sowing a crop so that these material
  will have time to further decompose in the soil
  to provide the benefits from their application.

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• A. Use of organic manures
• Green manuring
• The application of limited quantities of
  available organic manures can be supplemented by
  green manuring.
• Green manuring is the practice of growing a
  short duration, succulent and leafy legume crop,
  and ploughing the plants in the same field before
  they form seeds.
• Sesbania, Crotalaria, Pillipesara (Phaseolus
  trilobus), Cowpea etc are good green manuring
  crops.

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• A. Use of organic manures
• Green manuring
• Sesbania
  Crotalaria

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• A. Use of organic manures
• Green manuring
• A green manure crop not only enhances the
  organic matter of a soil but also
• Reduces loss of nitrogen and other nutrients
• Suppresses weed growth
• Provides material for composting
• Shelters the soil from beating action of rains.

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• B. Adding off-field organic material
• To further supplement the availability of
  limited quantities of organic manures, one can
  also incorporate the green loppings brought
  plants/trees in and around the farm. This
  practice is called green leaf manuring.
• It will be a good practice to establish plants
  like Glyricidia, Pongamia etc on the field bunds
  so that the loppings from these plants can be
  used for green leaf manuring.

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• B. Adding off-field organic material
• Glyricidia
  Pongamia

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• C. Growing of cover crops
• Cover crop refers to a field or forage crop
  grown particularly to cover the soil. The cover
  crop also can be later incorporated as green
  manure.
• Cover crops mainly acts as a live mulch
  protecting the soil from erosion possibilities.
• Cover cropping is also practiced to benefit
  from any fertilizer residues and available
  moisture in the soil.

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• C. Growing of cover crops
• Cover crops provide significant benefits to soil
  including providing nutrients, nutrient cycling,
  weed control, soil protection and soil
  improvement.
• These benefits vary mainly based on the
  management practices, and climate affecting the
  quantity and timing of biomass produced. 

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• C. Growing of cover crops
• The popular cover crops are short duration
  legume crops like horse gram, black gram, green
  gram, cowpea etc.

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• C. Growing of cover crops
• The dominant forage species are
• Sehima nevosum,
• Dichanthium annulatum,
• Iseilema laxum,
• Ischaemum indicum,
• Themeda triandra,
• Chrysopogon fulvus and
• Heteropogon contortus.

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• C. Growing of cover crops
• Cover crop of cowpea Forage
  grass as cover crop

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• D. Adopting suitable crop rotation
• Crop rotation refers to planned way of
  growing crops in a sequential and systematic
  manner on the same piece of land so that the
  farmer, as well as the soil will be benefited.
• The planned crop rotation sequence may be for
  one to two- or three-year or longer period.
• For example
• One-year rotation sorghum followed by
  chickpea
• Two-year rotation cotton in the year one
  and
• chilies in
  the year two.

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• D. Adopting suitable crop rotation
• Some of the more important beneficial effects
  that can be obtained from a well planned crop
  rotation are
• Improved soil fertility
• Improvements in soil tilth and aggregate
  stability
• Reduced insect and disease problems
• Soil water management
• Reduction of soil erosion
• Reduction of any toxic effects from crops
  grown continuously every year in the same
  field.

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• D. Adopting suitable crop rotation
• When selecting a rotation, the long-term
  viability of that rotation to reduce weed, insect
  and disease pressure, as well as its income
  potential must be considered.
• A well developed plan should consider alternate
  crops when necessary. For example, if rains are
  delayed planned sorghum crop need to be replaced
  with a pearl millet crop for better yields under
  such conditions.

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• D. Adopting suitable crop rotation
• The following are important to consider when
  designing a crop rotation, regardless of
  location. They are
• How will the previous crop affect subsequent
  crop production?

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• D. Adopting suitable crop rotation
• Will the previous crop increase or
  decrease
• concerns in the following areas?
• Disease management
• Insect management
• Weed control and volunteer crop control
• Residue management
• Soil moisture returns
• Seedbed preparation
• Harvest and planting schedule
• Gross economic returns

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

• This concludes the Lesson 1 Improving and
  maintaining organic matter- in this Module.
• Next, Lesson 2 in this Module is about
  tillage practices that affect the soil health and
  how to improve soils affected by such wrong
  tillage practices.
• Soil degradation and practices to improve the
  degraded soils are discussed in the subsequent
  Lessons in this Module.
• Select Lesson 2 in Module III from the list of
  course contents

Course on Soil and Soil Health