Soil Fertility and Nutrient management (1+1)

Factors affecting Soil Productivity

• The factors affecting soil productivity include all those which affect the physical, chemical and biological conditions of the soil environment in which plants grow. They include all the practices that affect fertility, the water and air relationships and the activity of the biological agents such as insects, pests, diseases and microorganisms.

  I. Internal factors: may be called as genetic or hereditary factors which cannot be manipulated such as soil type, texture etc.
  II. External factors: may be regulated to certain extent, They include
  a. Climatic factors: like precipitation (rain fall), solar radiation, atmospheric gases (CO2, NO2, N2O, O2), wind velocity etc.
  b. Edaphic or Soil factors: Soil moisture, soil air, soil temperature, soil mineral matter, inorganic and organic components, microorganisms, soil reaction.
  c. Biotic factors:
  i. Plants: have competitive and complementary nature, competition between weeds and crop plants, plants growing as parasites.
  ii. Bacteria of symbionts, free living.
  d. Animals: earth worms, small and large animals
  e. Physiographic factors: geological strata (parent materials), topography (altitude, steepness of slope)
  f. Anthropogenic factors: human factors including skill and efficiency of cultivation by man.