Question

What is meant by concentrated organic manure and macro-organic manure?

Answer 1

Organic manures are the organic material obtained from the animal and plant residues and human excreta. These manures contain plant nutrients in complex organic forms. Organic manures or synthetic chemicals containing plant nutrients are known as fertilizers.

Complete answer:
Concentrated organic manure: These manures are organic in nature and contain large amounts of plant nutrients like Nitrogen, Phosphorus oxide and Potassium oxide. Concentrated organic manures are made from raw materials obtained from animals and plants, e.g., oil cakes, blood meal and fish manure, meat etc which contains iron, calcium, nitrogen and phosphorus.
Characteristics features of concentrated organic manure:

Water holding capacity is increased by organic manures.
Organic manures help to reduce the alkalinity in soils.
Fresh organic manures are a source of food for earthworms, ants and rodents. These organisms improve drainage and aeration.
Macro-organic manure: These manures are also organic in nature. Macro-organic manures mainly consist of the three macronutrients nitrogen, phosphorus and potassium.
The phosphorus, nitrogen and potassium are the macronutrients and their deficiency in plants causes severe problems. Phosphorus is the second important nutrient required by plants. It stimulates growth of plant, flowering and seed development. Potassium increases resistance towards disease and promotes formation of carbohydrates and proteins in plants. Nitrogen promotes growth of leaves and stems. It is necessary to develop cell proteins and chlorophyll.

Note: Organic manures are much more expensive and contain low amounts of nutrients. A large amount of manure has to be added for the good crop. The production of organic manure is a very complex process and financially weak farmers cannot afford these manures.