Reverse the ill Effect of Soil Mining of Nutrients
Promoting Tenets of Sustainable Agriculture
Response of Fertilizers Declining due to
Sub-optimal and Imbalance in Fertilizer Use
Inappropriate Methods and Time of Application
Lesser Use of Organic Manure
INM Must for the Desired Results
The key objectives of Integrated nutrient supply
To maintain or enhance soil productivity through balanced use of mineral fertilizers combined with organic and biological sources of plant nutrients.
To improve the stock of plant nutrients in the soil.
To improve the efficiency of plant nutrients, thus limiting losses to the environment.
To improve physical condition of soils.
Major Sources of Nutrients Component Desirable effect Other effect Fertilizers Concentrated source Concentrated source Concentrated source Less nutrients but Improves soil physical properties Immediate crop need not met Green manure Sources of N from the atmosphere Crop competition Crop residues Source of K. Mulching has (+)ve effect on soil properties Immobilization of nutrients More fertilizer needed. Crop rotation (other crop - legume ) N fixed by legumes Improves soil permeability little N fixed available to the rotation crop Rhizobium, Azospirillum. and BGA Mycorrhiza and P solubilizers N fixers P solubilizers Small amounts of N fixation Small P solubilized
Some key points regarding integrated nutrient supply
Fertilizers and manures contribute about 50-60% increase in productivity of food grains irrespective of soil and agro-ecological zone.
For the land short countries like India, use of fertilizers provide the best strategy for land saving.
In soils of low pH, nitrogen fertilizer application alone further increase the soil acidity.
Soil fertility status of Indian soils Nutrient Soil fertility status Nitrogen Low in 228 districts, medium in 118, high in 18 districts Phosphorus Low in 170 districts, medium in 184, high in 17 districts Potassium Low in 47 districts, medium in 192, high in122 districts Sulphur Deficiencies scattered in 100-120 districts Magnesium Kerala, other southern states, very acid soils Zinc 50% of 150,000 soils analyzed found deficient Iron On upland calcareous soils rice, groundnut, sugarcane Boron Parts of Bihar, Karnataka, West Bengal
Animal Dung Human Excreta, Recycling of Plant Resources and City Wastes
Organic Sources Neither Nutrient Specific nor Concentrated Sources
For Nutritional Benefits, Organic Sources to be Decomposed
Microorganisms Engineer Their Break Down
Temperature and Moisture Conditions Influence the Decomposition
C: N ratio Decides the Time Lag for Nutrients to Become Plant Usable
Nutrient Supply from Organic Sources Remains low, Variable and Uncertain
Second Largest Population ( About 110 crores)
Higher Number of Livestock (492 Millions)
Seventh Largest Geographical Area (329 Million ha)
A Vast Pool of Organic Manure for Nutrient Availability
Organic Manure Potential = 16.9 Million Tonnes of NPK
85 per cent Arises from Animal Dung, Crop Residues and Human Excreta
About 5.65 mt NPK Available for Agricultural Use
Consumption of major fertilizers (in lakh tonnes) Fertilizer 2002-03 2003-04 2004-05 2005-06 urea 184.93 197.67 206.65 222.97 DAP 54.73 56.24 62.56 67.64 MOP 19.12 18.41 24.06 27.31 N 104.74 110.77 117.13 127.23 P 40.19 41.24 46.24 52.04 K 16.01 15.98 20.61 24.13 N+P+K 160.94 167.99 183.98 203.40
Balance sheet of Nutrients Nutrient removal by crop 32 mt Nutrient addition through fertilizers 16.8 mt Nutrient addition through FYM 3.8 mt Nutrient addition through Biofertilizers 1.0 mt Nutrient addition through agricultural wastes 2.0 mt Nutrient addition through other sources 1.0 mt Total Addition 24.6 mt Mining of soils 7.4 mt per yr
Projected food grain production in relation to nutrient (N-P2O5-K2O) consumption, removal and gap