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Productivity. (a)1.65 t/ha (b)490 mm (c)too much water rots the plant inadequate aeration nutrient deficiency toxic concentration of some element. strong / high positive correlation
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(a)1.65 t/ha (b)490 mm (c)too much water rots the plant • inadequate aeration • nutrient deficiency • toxic concentration of some element
strong / high positive correlation It means that a higher percentage of cultivated land under irrigation will most probably lead to higher percentage of total food production from irrigated land
Adding water provides optimal conditions for plant growth; • Adding water extends growing season; • Irrigation may permit more than one crop per year; • Stable water supply provides stable yield; • Irrigation may increase the intensity of land use • Irrigation may allow the introduction of high yielding variety
Consequence of Green Revolution in developing countries polarization of society high yields do not always mean high return for the farmers because prices may be lowered. Thus income is not guaranteed. Those who benefit most are : government bureaucrats (from corruption), international companies (from selling factors of production), landlords (from controlling more land and exporting more farm products),
and industrialist (from lower wages due to more abundant supply of food). Investment Is always concentrated on the land controlled by landlords many farmers do not want to risk bad harvest. Some are too conservative to try new crops many owner-occupiers suffer from bankruptcy when they are unable to re-pay their debts.
As a result, they have to sell their land, always at much lower prices, to landlords, and they become farm labourers or tenants in order to minimize cost and avoid crop-sharing with the tenants, landlords always introduce mechanization to their farms. They may stop renting their lands and start large-scale commercial farming by employing farm labourers
higher productivity will result in higher land price, it will result in higher rents for tenants, higher taxes for owner-occupiers and attract speculation on land (by both landlords and capitalists from the city)
food supply to the rural population disturbed as owner-occupiers and tenants lose their farms, crop-sharing replaced by cash tenancy and farming becomes export-oriented, with the choice of crop depending on external demand
agricultural production, export and GNP of the country may be higher, but there would be a tremendous loss in foreign currency due to the import of machines, seeds, chemical fertilizers and pesticides locally developed hybrids are always neglected, but they are always more adaptable to the local environment than the imported ones
good farming practices for soil conservation are neglected, and are replaced by increasing application and reliance on chemicals
Nearest Neighbour Analysis Rn is the nearest neighbour value D(obs) is the average of all the distance between the settlements (points) and the nearest settlement (neighbour) to these settlements (points) A is the area under study (km2) N is the total number of settlements (points)
If D(obs)=0 Rn=0 All points aggregate/cluster together.
If Rn=1 Random distribution
If Rn=2.15 Regular distribution