Soil protection and soil amelioration

Question 1

1. Definition soil protection soil amelioration

Answer 1

Soil protection (pre-activity) involves protecting the soil so as to retain its functions.

Soil amelioration (post-activity) on the other hand is the improvement of soil structure through mechanical inputs (carbon) with the primary aim of improving air and water balance within the soil.

Question 2

2. Describe in keywords (in more detail) a soil problem and its solution (choose one)

Answer 2

Soil erosion: a phenomenon that happens either gradually or at an alarming rate causing the soil important particles to be leached or washed away by the forces of wind, water or human activities. It is natural process, but human activities such as deforestation, overgrazing, improper agricultural practices (ploughing, monoculture farming, improper irrigation) and construction (land clearing) can accelerate erosion rates. Soil erosion can result in loss of fertile topsoil, decreased soil fertility, sedimentation of water bodies and degradation of ecosystems, air pollution, desertification, destruction of infrastructure.

Solution: farming practices  Mulches, matting the soil, contour farming and terracing, manuring and fertilization, waterways, Sloping Agricultural Land Technology (SALT)
Stone walls, reforestation, conservation tillage, windbreaks

Question 3

3. Sketch/Describe the effects of soil compaction

Answer 3

• Smaller pore size and number
• Smaller Field capacity
• Decreased Aeration
• Decreased aggregate stability
• Increased penetration resistance
• Increased bulk density
• Decreased crop yield

Question 4

4. Describe the soil organic matter and how to improve this (list of measures)

Answer 4

• Usually 1–6% organic matter by weight (fresh residues, living organisms, humus, resistant organic matter)
• Stabilization of soil aggregates
• Increase of soil water-holding
• Buffering capacities
• Reservoir of nutrients
• Improvement measures:
  o Conservation tillage
  o Crop rotations
  o Adequate rate of fertilizer application
  o Organic manure
  o Preservation of pastures

Question 5

5. Why can biochar be valuable for soil?

Answer 5

• Reduces methane, N20 emissions
• Reduced nutrient leaching
• Increased soil carbon
• Increased water holding capacity
• Improved soil fertility
• Increased microbial biomass
• Bioremediation of pollutants