Difference between manures and fertilizers
| Manures | Fertilizers |
| Manures are defined as organic materials derived from plant and animal sources, which serve as valuable sources of essential nutrients for plants. | Chemical fertilizer is prepared by industrial process and it contains one or more synthetic nutrients that help in plant growth and yield. |
| Ex: manure, compost, vermiculture, green manure, oilcake etc | Ex: Nitrogenous fertilizer (Urea, Ammonium phosphate, ammonium sulphate) phosphate fertilizer (SSP, DSP, TSP), Potassic fertilizer (KCl, potassium nitrate). |
What are manures and fertilizers?
Manures
Manures are classified into two types based on nutrient concentration.
A. Bulk organic manures.
B. Concentrated organic manure.
A.BULK ORGANIC MANURES
like farmyard manure (FYM), compost, and green manures, they contain a small percentage of nutrients and they need to be applied in larger quantities to the field.
FYM
- FYM is a mixture of decomposition of farm animal dung, urine, and leftover material from fodder fed to cattle.
- Decomposed farmyard manure contains approximately 0.5 % N, 0.2 % P₂O₅, and 0.5 % K₂O.
- On average, an agriculture field needs 10-20 tons of decomposed FYM per hectare to enrich the soil.
- FYM is generally used as organic fertilizer for vegetables like potatoes, tomatoes, sweet potatoes, carrots, radishes, onions, etc, and flower crops.
- Not all the FYM nutrients are immediately accessible, around 30 percent of nitrogen, 60 to 70 percent of phosphorus, and 70 percent of potassium become available for the initial crop.
Compost
- Compost is the natural decomposition of plant matter and animal refuse (like sugarcane trash, and paddy straw) and food waste is called farm compost.
- compost made from various urban waste materials such as night soil, street sweepings, and dustbin refuse is commonly known as town compost
- Farm compost contains nutrients of approximately 0.5 percent nitrogen (N), 0.15 percent phosphorous (P₂O₅), and 0.5 percent potassium (K₂O).
- Town compost contains nutrients of approximately 1.4 percent nitrogen (N), 1.0 percent phosphorous (P₂O₅), and 1.4 percent potassium (K₂O).
Night soil
- Night soil refers to human excrement, including both solid and liquid waste. It contains higher levels of NPK, 5.5 percent N, 4.0 percent P2O5, and 2.0 percent K2O.
Vermiculture
- It is prepared from biodegradable waste into organic manure with the help of earthworms. Biodegradable material is cow dung, agriculture waste, forestry waste, etc.
- Vermiculture contains nutrients 3.0 % Nitrogen, 1.0 % phosphorous, and 1.5% potassium.
Vermiwash
- The liquid extract is derived from a nutrient-rich vermicompost medium called vermi-wash.
- Vermiwash is helping develop resistance against pests and diseases.
Green manure
- Green manuring is a beneficial technique where fresh, un-decomposed green plant material is incorporated into the soil. It helps to increase soil fertility and overall health of the soil.
- Green manure types: 2 types of green manure
- Green manuring crops or green manuring in site: Green manuring crop involves cultivating and incorporating these crops back into the soil, it helps to enrich soil nutrients and its structure.
- Sunnhemp, Dhaincha, sesbania rostrata, and cluster beans are the most commonly used green manure crops. Legume green manure crops are cowpea, horse gram lupin, etc.
- Green manure crops should be cut down before the flowering stage and it is used as manure.
- Green leaf manure crop: Collection of leaves, and twigs from shrubs and trees grown on bunds and nearby forest areas, these collected materials are then incorporated into cultivable fields.
- Gliricida sepium, Sesbania speciosa, Pongamia glabra, Ipomea, Jatropha gossipifolia are commonly used for green leaf manure crops.
Advantages of green manure
- On average, one ton of well-grown green manure is comparable to 2.8 to 3.0 tons of Farm Yard Manure (FYM) or approximately 4.5 to 4.7 kilograms of nitrogen. This nitrogen content is equivalent to 10 kilograms of urea.
- The water-holding capacity of the soil is improved, reducing water runoff.
- Green manure encourages the proliferation of beneficial microbial populations within the soil, contributing to improved soil fertility.
- It contributes nitrogen ranging from 50 to 175 kilograms per hectare.
Seep and Goat manure
Sheep and goat droppings possess higher nutrient content compared to farmyard manure and compost, with an average composition of 3 % nitrogen, 1 % phosphorus, and 2 % potassium.
Poultry manure
Bird excreta undergoes rapid fermentation, and if left exposed, approximately 50 percent of its nitrogen content is lost within a span of 30 days. And this manure contains 3.023 % nitrogen, 2.63 % phosphorus, and 1.4 % potassium.
B. CONCENTRATED ORGANIC MANURE
- Concentrated organic manure contains a higher concentration of nutrients compared to bulky organic manure. Like oilcakes, blood meal, fish manure, etc.
- These fertilizers, commonly referred to as organic nitrogen fertilizers, play a crucial role in providing nitrogen to crops.
- Oil cakes: Once the oil is extracted from oilseeds, the leftover solid portion is dried to create a nutrient-rich cake that serves as an excellent organic manure for enhancing soil fertility and promoting plant growth. Ex: Groundnut cake, coconut cake, etc.
- Other Concentrated organic manure: fish meal, meat meal, bird guano, etc
Fertilizers
Fertilizers are organic or inorganic materials of natural or synthetic origin that are added to the soil to supply certain elements essential to the growth of plants.
Classification of fertilizer
- Straight fertilizer: Such as Urea, fertilizer provides just one key nutrient.
- Complex fertilizer: Such as DAP, a fertilizer that blends two or more of the primary fertilizers.
- Mixed fertilizer: Products are made by mixing two or more fertilizers. Ex: NPK
- Complete fertilizer: Such as NPK, fertilizer has three major nutrients.
- Low analysis fertilizers: Fertilizer has less than 25% of the primary nutrients. Ex: SSP
- High analysis fertilizer: Fertilizer contains more than 25% of the total primary nutrient. Ex: Urea.
Also, visit Organic Fertilizer and Bio-fertilizer, Soil-fertility and soil-productivity, Types of farming system, and Ashwagandha cultivation
Types of fertilizer
Nitrogenous fertilizer
- Nitrate form– Sodium nitrate, Calcium nitrate
- Ammonical form– Ammonium phosphate, ammonium chloride, ammonium nitrate.
- Amide form– Urea, Calcium cyanide
Phosphatic fertilizer
- Water soluble: Single super phosphate (SSP), Double super phosphate (DSP), Triple super phosphate (TSP).
- Citric acid soluble: Di calcium phosphate, basic slag.
- Insoluble: Rock phosphate, rock bone meal.
Potassic fertilizer
- Murate of potash (KCL/MOP)
- Potassium sulphate (K2SO4)
- Potassium nitrate (KNO3)
