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Agricultural Systems and Food Production

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Presentation on theme: "Agricultural Systems and Food Production"— Presentation transcript:

1 Agricultural Systems and Food Production
Intensive Rice Production in the Lower Ganges Valley A Case Study of an Arable System

2 Introduction Shifting cultivation and nomadism are forms of subsistence agriculture found in regions of low density. (Why?) However, ¾ of the world’s people live in densely packed LEDC’s which need another type of subsistence farming to provide food. Intensive subsistence agriculture involves using a small amount of land to produce as much food as possible. No land is wasted. Roads are narrow, crops are grown in layers, and hillsides are terraced to produce usable growing areas. In Asia, agriculture can be divided between areas where wet rice is grown and areas where it is not grown.

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4 Intensive Subsistence Wetland Rice Cultivation
This farming system is dominated by intensive subsistence wetland rice cultivation carried out by farmers and sharecroppers in fragmented fields with or without irrigation. The system is concentrated in Bangladesh and West Bengal, but smaller areas are found in the states of Andhra Pradesh, Tamil Nadu and Kerala, and Southern Sri Lanka. The system also contains 50 million bovines (used for draught power, milk and manure) and a considerable number of small ruminants. Poor farmers operate extremely small areas, and rely on off-farm income for survival. Poverty is extensive and also quite severe.

5 Intensive Wetland Rice Cultivation

6 Introduction An important area of intensive subsistence wetland rice cultivation is the Lower Ganges valley in India and Bangladesh. The Ganges basin is India’s most extensive and productive agricultural area and its most densely populated. The delta region of the Ganges occupies a large part of Bangladesh, one of the most densely populated countries in the world. Rice contributes over 75% of the diet in many parts of the region.

7 Location of the system Divisions of the Great Plains (after Singh ): 1. Punjab-Rajasthan Plain; 2. Upper and middle Ganges plain / basin 3. Lower Ganges plain / delta 4. Assam Valley

8 Physical requirements
The physical conditions in the Lower Ganges valley and delta are very suitable for rice cultivation: Temperatures of 21 ° C and over throughout the year allow two crops to be grown annually. Rice needs a growing season of only 100 days. Monsoon rainfall over 2000mm provides sufficient water for the fields to flood, which is necessary for wet rice cultivation. Rich alluvial soils have built up through regular flooding over a long time period during the monsoon season. There is a seasonal dry period, which is important for harvesting the rice. CLIMATIC GRAPH FOR KOLKATA

9 The Rice Farming System - Introduction
Rice is the staple or main food crop in many parts of Asia. This is not surprising considering its high nutritional value. Current rice production systems are extremely water- intensive; 90% of agricultural water in Asia is used for rice production. The International Rice Research Institute estimates that it takes litres of water to produce 1 kilogram of rice. Much of Asia’s rice production can be classed as intensive subsistence cultivation where the crop is grown on very small plots of land using a very high input of labour. Rice cultivation by small farmers is sometimes referred to as ‘pre-modern intensive farming’ because of the traditional techniques used, in contrast to intensive farming systems in HICs such as market gardening, which are very capital intensive.

10 The Rice Farming System – Physical Inputs
‘Wet’ rice is grown in the flat, fertile silt and flooded areas of the lowlands, while ‘dry’ rice is cultivated on terraces on the hillsides. A terrace is a levelled section of a hilly cultivated area. Terracing is a method of soil conservation. It also prevents the rapid runoff of irrigated water. Dry rice is easier to grow but provides lower yields than wet rice. Farms are generally small, often no more than 1 hectare.

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12 The Rice Farming System – Physical Inputs
Paddy fields (flooded parcels of land) characterise lowland rice production. Water for irrigation is provided either when the Ganges floods or by means of gravity canals. At first, rice is grown in nurseries. It is then transplanted when the monsoon rains flood the paddy fields. The flooded paddy fields may be stocked with fish for an additional source of food. The main rice crop is harvested when the drier season begins in late October. The rice crop gives high yields per hectare. A second rice crop can then be planted in November, but water supply can be a problem in some areas for the second crop. During the dry season when there may be insufficient water for rice cultivation, other crops such as cereals and vegetables are grown. Rice seeds are stored from one year to provide the next year’s crop.

13 The Rice Farming System – Human Inputs
Water buffalo are used for work. This is the only draft animal adapted for life in wetlands. The animal also provides an important source of manure in the fields. However, the manure is also used as domestic fuel. The labour-intensive nature of rice cultivation provides work for large numbers of people. This is important in areas of very dense population where there are limited alternative employment opportunities. The low incomes and lack of capital of these subsistence farmers mean that hand labour still dominates in the region. It takes an average of 2000 hours a year to farm 1 hectare of land.

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15 The Rice Farming System – Human Inputs
A high labour input is needed to: build the embankments (bunds) that surround the fields – these are stabilised by tree crops such as coconut and banana. construct irrigation canals where they are required for adequate water supply to the fields. plant nursery rice, plough the paddy field, transplant the rice from the nursery to the paddy field, weed and harvest the mature rice crop. cultivate other crops in the dry season and possibly tend a few chickens or other livestock.

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17 Issues Land Tenure: Many farmers are tenants and pay for use of the land by giving a share of their crop to the landlord. Shortage of Land: Even though land reform is over 50 years old in some countries, there is still a shortage of land and many farms are too small to support a farmer and his family. When this shortage is coupled with the rapidly growing regional population, this will lead to food shortages. Wastage: In some cases there is considerable wastage of nutrients - particularly nitrogen in irrigated and wetland cultivation - due to low efficiency in the use of fertiliser.

18 Issues Drought: Floods: Environmental:
In some cases the monsoon rains ‘fail’ and the crop is ruined. Since it is a subsistence crop this leads to a problem for the farmer and he is forced to seek off-farm employment. Floods: Flooding provides the water and silt to grow the crop. However, sometimes the flooding is so severe it destroys the crop. Environmental: Continuously flooded rice paddies account for 25% of the methane released into the atmosphere.

19 Issues Stagnation: Poverty:
A stagnation in production and productivity on the late 1990s coupled with declining soil fertility and increased nutrient mining. Poverty: Poverty levels are high.

20 Rice farming as a system
Physical Inputs 5 month growing season Annual floods deposit rich layers of alluvium that provide nutrients and an impermeable layer. Monsoon rainfall > 2000mm Flat land for flooding Temperatures over 21ºC Dry time for harvesting Processes Ploughing Planting Harvesting Threshing Weeding Constructing bunds and canals Outputs Rice Rice seeds Human Inputs Rice seeds Large labour force Water buffaloes for ploughing Manure from buffaloes for fertilising

21 A Typical Household of the Rice Farming System
A typical poor sharecropping household with five family members within the Rice Farming System cultivates 0.4 ha of irrigated land in West Bengal, India. A second irrigated rice crop and a short vegetable crop follow the kharif (monsoon) rice crop. Modern rice varieties are transplanted in both seasons, producing typical yields of 1.9 and 2.4 t/ha, of which the sharecropper retains one third since the landowner provided the land, as well as a draught buffalo and crop inputs (including fertiliser, about 150 kg/ha of nutrients and chemicals for about four sprays per season). The household owns two goats and some ducks and chickens and plans to join with a relative to purchase a milking buffalo. Both adults work for about 120 days a year on nearby large farms and in a local factory. The household has a very low annual income, and is vulnerable to low crop yields or lack of labour earnings due to sickness or lack of work opportunities.

22 Recent Changes: Land Reform
Many farms are very small and broken up in tiny plots that are spread over a wide space. This makes efficient farming difficult. Most poor farmers have no land and live in poverty. In contrast the few wealthy people own much of the farm land. The three aims of land reform are: to increase farm size for those with little land, to give any surplus land to the landless, and set an upper limit to the amount of land that a wealthy family can own.

23 Recent Changes: Green Revolution
Green Revolution refers to the applications of modern farming systems. It began with the development of high yielding varieties (HYVs). Even though the new seeds are faster growing and resistant to diseases they needed a lot of pesticides and fertilizers making farming sustainable.

24 Green Revolution in India
High Yielding Varieties (HYVs), such as IR8, were introduced in the 1960s. Resulted in a tripling of rice production. Advantages Disadvantages Allowed a more varied diet as higher yields meant that some fields could be used for other crops, such as vegetables. HYVs needed a reliable and controlled water supply and greater amounts of machinery which increased farmers’ costs Yields were more reliable as new varieties were disease resistant Only farmers who could have afforded to invest benefitted Faster growing HYVs allowed an extra crop to be grown each year. Increased used of pesticides poisoned other forms of wildlife Greater production meant an enhanced quality of life with more money for better roads and housing Mecahnisation lead to rural unemployment and migration to overcrowded cities Increased yields would have meant a drop in food prices for local people in rural areas Those who could not have afforded the extra cost of mecahnisation ran into debt and were forced off their land.

25 Recent Changes: Appropriate Technology
In the Ganges Basin this includes: the building of simple, easy to build, easy to maintain water pumps, projects that use human labour rather than machines such as tractors, low-cost irrigation schemes instead of building large dams, and the use of animal manure than chemical fertilizers. Such schemes are said to be sustainable because they are affordable and help to improve peoples standard of living and quality of life without damaging the environment.

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27 Recent Changes – System of Rice Intensification (SRI)
An agro-ecological approach introduced in the late 1980s. Initially developed for irrigated rice, it has been successfully adapted to rain-fed lowland and upland systems Allows farmers to increase yields while decreasing inputs such water, seeds, chemical fertilisers, herbicides and pesticides. Allows for a reduction in methane production. Works well with appropriate technology.

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