1. FOOD RESOURCES WORLD FOOD PROBLEMS
CHANGES CAUSED BY AGRICULTURE AND OVER GRAZING
EFFECTS OF MODERN AGRICULTURE
FERTILIZERS-PESTICIDES PROBLEMS
WATER LOGGING
SALINITY
CASE STUDIES

2. Food Resources Food from agriculture, animal husbandry and fishing.
India is self sufficient in food production
Excessive use of fertilizers, pesticides….problem.
The FAO (Food and Agriculture Organization) defines sustainable agriculture:
One which conserves land, water and plant and animal genetic resources ,does not degrade environment and is economically viable and socially acceptable.
Monoculture

3. World food problems Production of food vs growing demand
Food production in 64 of the 105 developing countries is lagging behind their population growth levels.
The Green Revolution of the 60’s reduced starvation in India
But…
Our fertile soils r being exploited faster
Forests, grass lands and wet lands were converted to agricultural use
Our fish resource show evidence of exhaustion
Disparities in availability of nutritious food

4. Globally 5 to 7 million ha of farm land is degraded each year.
18 million people world wide most of them r children, die each year due to starvation or malnutrition.
FAO reported that 44% of the world’s fisheries r fully exploited -16% r already overexploited, 6% r depleted and only 3% r gradually recovering.
If plant genetic losses world wide r not slowed down, some estimates show that >60000 plant species, which accounts for 25% of the world’s total will be lost by the year 2025

5. WORLD/GLOBAL FOOD PROBLEMS
Food supply improved since 1960
More favorable condition in 1980 and 1990
Food production increased by 18% compared to 30 years ago
In 1990 global grain yields per hectare were approx: tons (1.15 in 1930)
FAO : Food and agricultural organization
ICID : International commission on Irrigation and drainage (Food production should double in next 25 years)  More crop per drop

6. WORLD/GLOBAL FOOD PROBLEMS
ICD Estimated current food production would have to double with in next 25 years
More enough food for every person on the planet, many times the poor do not have access to food  due to economic and social progress is not occurring at similar rates across countries
Green revolution in (after food crisis) : crop variety improvements, increased use of fertilizers and expansion irrigation
CGIAR (Consultative group on International agricultural Research), says world is entering 21st century , food crisis is more dangerous than 1960’s

7. FOOD SECURITY
Food Security is the ability of all people at all time to access enough food for an active and healthy life
FOOD MUST BE AVAILBLE
EACH PERSON MUST HAVE ACCESS TO IT
THE FOOD UTILIZED MUST FULFILL NUTRITIONAL REQUIREMENTS.
In Nov’1996, World leaders assembled in Rome, FAO, The participants pledged by 2015 to reduce the current no of hungry people by half.

8. Fisheries In 1995 FAO reported that – 44% - fully or heavily exploited
16% - already over exploited
6% - depleted
3% - gradually recovering
Modern fishing – mechanized trawlers and small meshed nets leads to over exploitation , not sustainable

9. Loss of genetic diversity
50,000 known edible plants – 15 varieties produce 90% of world’s food.
Cereal that has multiple varieties growing in different locations does not permit rapid spread of disease.
60,000 plant species, 25% of world’s total will be lost by 2025
Collection in germplasm, seed banks and tissue culture facility prevents extinction

10. To meet future needs -
Reduction of dependence on fertilizers or pesticides
Pollution of water resources, land degradation and desertification must be reversed rapidly
Soil conservation measures, appropriate farming techniques, especially on hilly slopes.
Enhancing soil with organic matter, rotating crops and managing watersheds at micro level
Alternate food sources – fruits, mushrooms etc.,

11. Impacts of overgrazing
Land degradation- removes the green cover and soil becomes hard
Soil erosion
Loss of useful species – due to grazing root stocks thus soil loses its regenerating capacity

12. Modern Agriculture Impacts
Impacts related to High Yielding Varities – encourages monoculture, devastation pof crop in case of attack by pathogen
Fertilizer related problems
Micronutrient imbalance – Macronutrients (N,P,K) if used indiscriminately leads to deficiency of micronutrients. Ex: Punjab, Haryana

13. Modern Agriculture Impacts
2. Fertilizer related problems
b) Nitrate pollution –if concentration of nitrates in water exceeds 25 mg/L causes Blue baby syndrome or methaemoglobinemia – affects infants, causes death. Ex: India, Denmark, England, France

14. Modern Agriculture Impacts
2. Fertilizer related problems
c) Eutrophication – due to excessive use of N, P lakes gets invaded by algal blooms. They die quickly causing fish death.
3 . Pesticide related problems
Creating resistance is pests and producing new pests
Death of non target organisms
Biological magnification

15. Modern Agriculture Impacts
4. Water logging – caused by over irrigation. Preventing excessive irrigation, sub-surface drainage and biodrainage with trees like Eucalyptus are some measures of prevention.
5. Salinity – 1/3 of total arable land(world) is affected by salts (seven million hectares in India)

16. Salinity
Saline soils are characterized by accumulation of soluble salts like NaCl, Sodium Sulphate, Calcium Chloride, Magnesium Chloride, Bicarbonates and Carbonates of Sodium, pH>8.0 and Exchangeable Sodium Percentage (ESP) > 15%

17. Salinity
Causes – excess irrigation. About 20% of croplands receive canal and ground water unlike rain water which often contain dissolved salts. Under dry climate water evaporates leaving behind the salts.
Remedy – flushing with good quality water, laying underground network of perforated drainage pipes for flushing out salts. This has been tried in experimental station of Central Soil Salinity Research Institute (CSSRI) Sampla, Haryana.