Application of inorganic fertilizers:Fertilizers are chemical substances, generally in the form of powder, granules, pellets or crystals which can be added to the soil to increase its fertility. The use of fertilizers is the surest way of replenishing lost nutrients from the soil and increase the productivity of crops.
USES OF FERTILIZERS IN AGRICULTURE(i) Fertilizers help to increase the yield of crops
(ii) They improve the structure of the soil
(iii) They increase the activities of soil organisms
(iv) They also improve soil aeration
(v) They increase the fertility of the soil
(vi) They increase the growth of planktons in fish ponds.
Types of FertilizersFertilizers are grouped into two major classes based on their composition:
(i) Straight or Single Fertilizers: These fertilizers contain only one element. Such element may be nitrogen, phosphorus and potassium.
(a) Fertilizers which are rich in nitrogen are called nitrogen fertilizers and examples include:
(1) Animonlum sulphate - (NH4),SO, 21%N,24%S
(2) Ammonium nitrate - NH4NO, 335%N
(3) Urea - CO(NH,), 46%N
(4) Sodium nitrate - NaNO, 16%N
(5) Potassium nitrate,
(6) Anhydrous ammonia,
(7) Ammonia liquor
(8) Calcium ammonium nitrate
(9) Dlammonium phosphate.
(b) Fertilizers which are rich in potassium are called potassium fertilizer and example is nitrate of potash – Kcl 50%K2O
(c) Fertilizers which are rich in phosphorus are called phosphorus fertilizers and examples include:
(1) Single super phosphate - CaNPO, 43.7%P
(2) Triple super phosphate - 45%.
(3) Rock phosphate
(4) Basic slag
(5) Dicalcium phosphate
(6) Diamrnoniurn phosphate
(7) Guano (poultry/bird droppings).
(ii) Complete or Mixed or Compound Fertilizers: These are fertilizers which contain two or more nutrients. A good example is
N.P.K. fertilizer, which contains nitrogen, phosphorus and potassium. Compound fertilizer can exist in various combinations such as 15-15-15, 20-5-10 and 5-10-5. 15-15-15 grade would haven l:1:1 ratio of N: P,O, :K2O. 15.15.15. means equal amount of nitrogen, phosphorus and potassium.
METHODS OF FERTILIZER APPLICATIONDifferent methods are used to apply fertilizers to the soil. These include:
(1) Broadcasting: This is the ground before they are ploughed into the soil.
(2) Ring method: A circular hole is made round the crop and fertilizer is placed inside the hole after which the hole is covered. The circular hole must not come too close to the plant, otherwise, fertilizer will touch the plant and burn it.
(3) Row or side placement: Make a hole a few centimeters from each plant and apply a teaspoonful of fertilizer per plant in each hole, then cover it up with soil. read how to properly apply fertilizer here
(4) Top dressing: This refers to the second application of fertilizer several weeks after the first dose had been applied. The second does it to supplement the first application.
(5) Folial spray: this is the method in which some trace elements or micro-nutrients are dissolved in water and sprayed on the crop directly. The leaves are capable of absorbing the nutrients directly into their body.
HERE YOU WILL FIND SOME AVAILABLE TOPICS ABOUT AGRICULTURAL SCIENCE AND BIOLOGY. AND THE LINKS TO THEIR VARIOUS SOURCES.
1. DEVELOPMENT OF AGRICULTURE
2. IMPORTANCE OF AGRICULTURE
3. SUBSISTENCE AGRICULTURE
4. COMMERCIAL AGRICULTURE
5. PROBLEM OF AGRICULTURAL DEVELOPMENT
6. SOLUTIONS TO POOR AGRICULTURAL DEVELOPMENT
7. AGRICULTURAL LAWS AND REFORMS
8. ROLES OF GOVERNMENT IN AGRICULTURAL DEVELOPMENT
9. AGRICULTURAL POLICIES
10. PROGRAM PLANNING IN AGRICULTURE
35. WILDLIFE CONSERVATION
39. BIOLOGICAL FACTORS
42. CLIMATIC FACTORS AFFECTING AGRICULTURAL PRODUCTION
47. SOLAR RADIATION
48. BIOTIC FACTOR AND AGRICULTURAL PRODUCTION
52. SOIL MICRO-ORGANISMS
53. SOIL PH
54. ROCK FORMATION
55. IGNEOUS ROCK
56. SEDIMENTARY ROCKS
58. SOIL AND ITS FORMATION
59. FACTORS OF SOIL FORMATION
60. LIVING ORGANISM
61. PARENT MATERIALS