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Determinants of Agriculture. Dr. Salve P.N. M.J.S.College Shrigonda. Indian Agriculture. Agriculture Sector is changing the socio-economic environments of the population due to liberalization and globalization
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Determinants of Agriculture Dr. Salve P.N. M.J.S.CollegeShrigonda
Indian Agriculture • Agriculture Sector is changing the socio-economic environments of the population due to liberalization and globalization • About 75% people are living in rural areas and are still dependent on Agriculture. About 43% of India’s geographical area is used for agricultural activity • Agriculture continues to play a major role in Indian Economy
Indian Agriculture • Provides about 65% of the livelihood • Accounts for 27% of GDP • Contributes 21% of Total Exports, and Supplies Raw materials to Industries • Growth Rate in production - 5.7% • Food grains production – 211.17mt
India’s position in world Agriculture Rank • Total Area Seventh • Irrigated Area First • Population Second • Economically Active population Second • Total Cereals Third • Wheat Second • Rice Second • Coarse grains Fourth • Total Pulses First • Oil Seeds Second • Fruits and Vegetables Second • Implements (Tractors) Third • Milk First • Live Stock (castles, Buffaloes) First
PHYSICAL DETERMINANTS • (i)Climate. • Climate plays a dominating role in agriculture. Plants require sufficient heat and moisture for their growth. Normally, regions having maximum temperature of less than 10°C are not suitable for plant growth. In the tropical regions, where temperature is high throughout the year, agriculture is successfully done. • (Most plants cannot grow if the temperature falls below 6°C or the soil is frozen for five consecutive months. As a consequence many areas are unsuitable for crop cultivation.) • Plant life is not possible in dry areas except that with the help of irrigation. The moisture requirements vary from plant to plant and region to region. In the lower latitudes, where temperature is high, plants need more moisture for their growth (75cm to 100cm). • On the other hand, in the higher latitudes where summers are cool, winds are not dry, rainfall of 50-62 cm is sufficient for plant growth.
The growing season: • The number of days between the last frost of the spring and the first of the autumn. Different crops require different lengths of growing season. Cotton needs 120 days so could not survive in India climate.
How Photosynthesis Works • Photosynthesis defines the process by which plants and some bacteria manufacture glucose. Scientists summarize the process as follows: using sunlight, carbon dioxide + water = glucose + oxygen. The process occurs within special structures called chloroplasts located in the cells of leaves. Optimum photosynthetic rates lead to the removal of greater amounts of carbon dioxide from the local atmosphere, producing greater amounts of glucose. Since glucose levels within plants are difficult to measure, scientists utilize the amount of carbon dioxide assimilation or its release as a means to measure photosynthetic rates. • During the night, for example, or when conditions are not prime, plants release carbon dioxide. Maximum photosynthetic rates vary between plant species, but crops such as maize can achieve carbon dioxide assimilation rates as high as 100 milligrams per decimeter per hour. To achieve optimum growth of some plants, farmers keep them in greenhouses that regulate conditions such as humidity and temperature. There are three temperature regimes over which the rate of photosynthesis changes.
Low Temperature • Enzymes are protein molecules used by living organisms to carry out biochemical reactions. The proteins are folded into a very particular shape, and this allows them to bind efficiently to the molecules of interest. At low temperatures, between 32 and 50 degrees Fahrenheit – 0 and 10 degrees Celsius – the enzymes that carry out photosynthesis do not work efficiently, and this decreases the photosynthetic rate. This leads to a decrease in glucose production and will result in stunted growth. For plants inside a greenhouse, the installation of a greenhouse heater and thermostat prevents this from occurring.
Medium Temperatures • At medium temperatures, between 50 and 68 degrees Fahrenheit, or 10 and 20 degrees Celsius, the photosynthetic enzymes work at their optimum levels, so photosynthesis rates gauge high. Depending on the particular plant in question, set the greenhouse thermostat to a temperature within this range for best results. At these optimum temperatures, the limiting factor becomes the diffusion of carbon dioxide into the leaves.
High Temperatures • At temperatures above 68 degrees Fahrenheit, or 20 degrees Celsius, the rate of photosynthesis decreases because the enzymes do not work as efficiently at this temperature. This is despite the increase of carbon dioxide diffusion into leaves. At a temperature above 104 degrees Fahrenheit – 40 degrees Celsius – the enzymes that carry out photosynthesis lose their shape and functionality, and the photosynthetic rate declines rapidly. The graph of photosynthetic rate versus temperature presents a curved appearance with the peak rate occurring close to room temperature. A greenhouse or garden that provides optimum light and water, but gets too hot, produces less vigorously.
Growing degree-day • In the absence of extreme conditions such as unseasonal drought or disease, plants grow in a cumulative stepwise manner which is strongly influenced by the ambient temperature. Growing degree days take aspects of local weather into account and allow gardeners to predict (or, in greenhouses, even to control) the plants’ pace toward maturity. • Unless stressed by other environmental factors like moisture, the development rate from emergence to maturity for many plants depends upon the daily air temperature. Because many developmental events of plants and insects depend on the accumulation of specific quantities of heat, it is possible to predict when these events should occur during a growing season regardless of differences in temperatures from year to year. Growing degrees (GDs) is defined as the number of temperature degrees above a certain threshold base temperature, which varies among crop species. The base temperature is that temperature below which plant growth is zero. GDs are calculated each day as maximum temperature plus the minimum temperature divided by 2 (or the mean temperature), minus the base temperature. GDUs are accumulated by adding each day’s GDs contribution as the season progresses. • GDUs can be used to: assess the suitability of a region for production of a particular crop; estimate the growth-stages of crops, weeds or even life stages of insects; predict maturity and cutting dates of forage crops; predict best timing of fertilizer or pesticide application; estimate the heat stress on crops; plan spacing of planting dates to produce separate harvest dates. Crop specific indices that employ separate equations for the influence of the daily minimum (nighttime) and the maximum (daytime) temperatures on growth are called crop heat units Tem. Maxi + Tem Mini • DD = ( ___30+ 16_________ - 10 ) X 1 2
Soils of India • (ii) Soils. • The richness of soil is another important physical factor affecting agriculture. Soils differ in respect of physical and chemical composition. Soils may be fine or coarse, porous or non-porous. In general fine soils like loam or silt are very fertile. The chemical composition of the soil determines its productivity. • Generally, the soils which are found at the place of their origin, known as residual soils, are poorer than those which have been transported from the place of their origin. The transported soils are rich and have a variety of minerals in them. The transported soils are: (a) loess, transported by wind (b) alluvial, transported by river water (c) glacial, transported by glaciers. • The fertility of the soils decreases with constant cultivation. Soils become infertile if the fertility is not renewed. This can be achieved by leaving the land fallow, by rotation of crop and by use of manures and fertilizers. • Soil erosion and water logging have become major problems with soils as such these should be checked by adopting contour farming, terrace farming, constructing dams and dykes. • Soil is our prime and natural resources as India is an Agrarian country, soil plays a vital role in the economy of India. • About 65 to 70% of the total population of the country is depended on agriculture .
Soil-water • Soil-water potential and hydraulic conductivity relationships with soil-water content are needed for many plant and soil-water studies. Measurement of these relationships is costly, difficult, and often impractical. For many purposes, general estimates based on more readily available information such as soil texture are sufficient. Recent studies have developed statistical correlations between soil texture and selected soil potentials using a large data base, and also between selected soil textures and hydraulic conductivity. The objective of this study was to extend these results by providing mathematical equations for continuous estimates over broad ranges of soil texture, water potentials, and hydraulic conductivities. Results from the recent statistical analyses were used to calculate water potentials for a wide range of soil textures, then these were fit by multivariate analyses to provide continuous potential estimates for all inclusive textures. Similarly, equations were developed for unsaturated hydraulic conductivities for all inclusive textures. While the developed equations only represent a statistical estimate and only the textural influence, they provide quite useful estimates for many usual soil-water cases. The equations provide excellent computational efficiency for model applications and the textures can be used as calibration parameters where field or laboratory soil water characteristic data are available. Predicted values were successfully compared with several independent measurements of soil-water potential
Soil Water Holding Capacity • Chemical water is an integral part of the molecular structure of soil minerals. It can be held tightly by electrostatic forces to the surfaces of clay crystals and other minerals and is unavailable to plants. The rest of the water in the soil is held in pores, the spaces between the soil particles. The amount of moisture that a soil can store and the amount it can supply to plants are dependent on the number and size of its pore spaces • Gravitational water is held in large soil pores and rapidly drains out under the action of gravity within a day or so after rain. Plants can only make use of gravitational water for a few days after rain. • Capillary water is held in pores that are small enough to hold water against gravity, but not so tightly that roots cannot absorb it. This water occurs as a film around soil particles and in the pores between them and is the main source of plant moisture. As this water is withdrawn, the larger pores drain first. The finer the pores, the more resistant they are to removal of water. As water is withdrawn, the film becomes thinner and harder to detach from the soil particles. This capillary water can move in all directions in response to suction and can move upwards through soil for up to two metres, the particles and pores of the soil acting like a wick.
When soil is saturated, all the pores are full of water, but after a day, all gravitational water drains out, leaving the soil at field capacity. Plants then draw water out of the capillary pores, readily at first and then with greater difficulty, until no more can be withdrawn and the only water left is in the micro-pores. The soil is then at wilting point and without water additions, plants die. • The amount of water available to plants is therefore determined by the capillary porosity and is calculated by the difference in moisture content between field capacity and wilting point. This is the total available water storage of the soil. The portion of the total available moisture store, which can be extracted by plants without becoming stressed, is termed readily available water. Irrigators must have knowledge of the readily available moisture capacity so that water can be applied before plants have to expend excessive energy to extract moisture.
In the modern period, when men started to know about the various characteristics of soil they began to classify soil on the basis of texture, colour, moisture etc. • When the Soil survey of Indiawas established in 1956, they studied soils of India and their characteristics. • The National Bureau of Soil Survey and the Land Use Planning, an institute under the control of Indian Council of Agriculture Research did a lot of studies on Indian soil. • Alluvial soil [43%] • Red soil [18.5%] • Black / regur soil [15%] • Arid / desert soil • Laterite soil • Saline soil • Peaty / marshy soil • Forest soil • Sub-mountain soil • Snowfields
Alluvial soil: Mostly available soil in India (about 43%) which covers an area of 143 sq.km. Widespread in northern plains and river valleys. In peninsular-India, they are mostly found in deltas and estuaries. Humus, lime and organic matters are present. Highly fertile. Indus-Ganga-Brahmaputhraplain, Narmada-Tapi plain etc are examples. They are depositional soil – transported and deposited by rivers, streams etc. Sand content decreases from west to east of the country. New alluvium is termed as Khadarand old alluvium is termed as Bhangar. Colour: Light Grey to Ash Grey. Texture: Sandy to silty loam or clay. Rich in: potash Poor in: phosphorous. Wheat, rice, maize, sugarcane, pulses, oilseed etc are cultivated mainly.
Red soil: Seen mainly in low rainfall area. Also known as Omnibus group. Porous, friable structure. Absence of lime, kankar (impure calcium carbonate). Deficient in: lime, phosphate, manganese, nitrogen, humus and potash. Colour: Red because of Ferric oxide. The lower layer is reddish yellow or yellow. Texture: Sandy to clay and loamy. Wheat, cotton, pulses, tobacco, oilseeds, potato etc are cultivated.
Black soil / regur soil: • Regur means cotton – best soil for cotton cultivation. • Most of the Deccan is occupied by Black soil. • Mature soil. • High water retaining capacity. • Swells and will become sticky when wet and shrink when dried. • Self-ploughingis a characteristic of the black soil as it develops wide cracks when dried. • Rich in: Iron, lime, calcium, potassium, aluminum and magnesium. • Deficient in: Nitrogen, Phosphorous and organic matter. • Colour: Deep black to light black. • Texture: Clayey.
Laterite soil: • Name from Latin word ‘Later’ which means Brick. • Become so soft when wet and so hard when dried. • In the areas of high temperature and high rainfall. • Formed as a result of high leaching. • Lime and silica will be leached away from the soil. • Organic matters of the soil will be removed fast by the bacteria as it is high temperature and humus will be taken quickly by the trees and other plants. Thus, humus content is low. • Rich in: Iron and Aluminum • Deficient in: Nitrogen, Potash, Potassium, Lime, Humus • Colour: Red colour due to iron oxide. • Rice, Ragi, Sugarcane and Cashew nuts are cultivated mainly.
Desert / arid soil: Seen under Arid and Semi-Arid conditions. Deposited mainly by wind activities. High salt content. Lack of moisture and Humus. Kankaror Impure Calcium carbonate content is high which restricts the infiltration of water. Nitrogen is insufficient and Phosphate is normal. Texture: Sandy Colour: Red to Brown. • Peaty / marshy soil: Areas of heavy rainfall and high humidity. Growth of vegetation is very less. A large quantity of dead organic matter/humus which makes the soil alkaline. Heavy soil with black colour. • Forest soil: Regions of high rainfall. Humus content is less and thus the soil is acidic. • Mountain soil: In the mountain regions of the country. Immature soil with low humus and acidic.
(iii) Topography. • The nature of topography plays a significant role in the development of agriculture. It determines extent of soil erosion, methods of cultivation and mode of transportation. In the mountanous and hilly regions, soil erosion is common; terrain restricts use of machinery and development of means of transportation. • However, in the flat regions, there is no such problem. Plain regions have fertile soils. The flat topography facilitates use of machines. Means of transportation can be easily developed in the plain areas. • Moreover, dense population in the plain regions provides cheap agricultural labour and a huge market for the products. The alluvial plains, the river valleys and the deltas are very suitable for agriculture.
2. Economic Factors • The most important economic factors affecting agriculture are: (a) market (b) transport facilities (c) labour (d) capital (e) Government policies. • (a)Market. • Market is an important economic factor in agriculture. The distance from the market determines the cost of transportation. Agricultural crops like vegetables etc. are grown near the market. • Sugarcane is grown close to the urban centres, where sugar mills have developed. Similarly, dairy farming is developed around the cities, which serve as markets for the dairy products.
(b)Transport Facilities. • The development of efficient means of transportation widen the market for agricultural products. • (c) Capital. • Agriculture, in the modern times is becoming mechanized. This involves huge capital investments. Purchase of machinery, fertilizers, pesticides and high yielding variety seeds require plenty of money. In India, the farmers are poor. • They cannot afford use of modern farm technology, thus it affects agricultural production. The factor of availability of capital plays a significant role in the development of agriculture. • (d) Labour. • The supply of labour determines the character and type of agriculture. Intensive cultivation requires a large supply of cheap labour. Availability of cheap and efficient labour is essential for the cultivation of crops like rice, tea, cotton and rubber. Thus, the factor of availability of labour also plays a vital role in agriculture.
(e) Government Policies. • The policies of the Government also influence agricultural land use. The Government may restrict the cultivation of a crop or may force the farmers to grow a particular crop, e.g., area under sugarcane and oil seeds cultivation has increased in India on account of greater emphasis put by the Government on these crops. • Government subsidy or liberal loan in respect of a particular crop helps in larger acreage under that crop. After 1947, the Government of India gave tax relief and concessions to the farmers for growing jute, with the result that in different parts of the country, area under jute cultivation had increased to a large extent.
3. Other Factors • (i) The level of scientific and technological development has a great bearing on agriculture. Farmers, using primitive methods obtain poor yields. But on the other hand, where farmers are using modern farm technology in the shape of fertilizers, pesticides, machinery and high yielding variety seeds etc. the farm yields are high. • An Indian farmer is poorer in comparison to an American farmer because the later uses modern farm technology. The per hectare yield of rice in India is only 2000 kg as compared to about 5600 kg in Japan. This difference in yield is due to scientific and technological differences. • The system of land tenure also plays a significant role in the patterns and productivity of agriculture crops
In common law systems, land tenure is the legal regime in which land is owned by an individual, who is said to "hold" the land. The French verb "tenir" means "to hold" and "tenant" is the present participle of "tenir". The sovereign monarch, known as The Crown, held land in its own right. All private owners are either its tenants or sub-tenants. Tenure signifies the relationship between tenant and lord, not the relationship between tenant and land.
Farm Size Farm size can affect land management in many, though sometimes inconsistent ways. Large holders are often more able than small holders to maintain traditional fallowing practices. They also can set aside a large portion of their holdings for non-food uses such as pasture or woodlot and other land-use practices that help control soil loss and fertility depletion. Moreover, because these farmers are also comparatively wealthy, they can invest more in inputs and improvements that will raise their long-term productivity . • Large holders also can endure the short- term consequences of taking land out of production to create space for anti-erosion technologies such as grass strips, trees, and hedge rows. Conversely, small farms in densely-populated regions of the world have a relative abundance of labor to construct and maintain terraces, hedge rows, drainage ditches, and other soil conservation measures. And those with small holdings often need more careful management with the related improvements in productivity. Their lower production level puts them closer to the margin and at greater risk should portions of their holdings fail to produce adequate yields.
Land Fragmentation • Both agricultural policymakers and social scientists often believe the division of farm holdings into many, disconnected, and increasingly distant parcels is detrimental to agricultural production. The focus of concern is on the high cost of moving laborers, equipment, and inputs to these many and sometimes distant holdings. In cases where agriculture is mechanized, there are additional problems. One is maneuvering large equipment in small fields; another involves production losses stemming from a high ratio of field edges to total area. • Conversely, there is a growing minority of researchers who have underscored the advantages to land fragmentation. These advantages include the farmer's ability to exploit a greater diversity of agroecological conditions. This, in turn, helps sequence crops and reduces the risk of total crop failure (Bently 1990). Igbozurike (1970) contends that fragmentation is actually beneficial to small farmers in West Africa simply because agroecological diversity allows for a greater number of farmers to survive. This occurs although very small field sizes may limit options for crop types and the introduction of mechanized production.
So what if CO2 goes up? Carbon dioxide is also the source of carbon for photosynthesis, and consequently for 99% of all life. CO2 + H2O + light O2 + organic C + chemical energy
Importance of Agriculture • Agriculture refers to the raising of crops and livestock by man to produce useful commodities. • It is a economic activity and the most basic of all. • Food supply, raw materials for industry • 2/3 people are engaged in various forms of agriculture all over the world. • It is a way of life. • Agricultural land occupies 33% of the earth’s land surface. (11% cropland, 22% pasture) • Farms products are very important elements in world trade. (many countries cannot produce enough food for their own needs)
Influence of the Environment • Physical factors set outer limits to farming (temperature, rainfall, landforms, soil types,growing season….) • Physical factors determine the outer boundaries for the production of particular crops or animals and the areas of optimum yields. (rice, wheat, sugar cane, dairying, …….)
Impacts on the Environment • Farmer is constantly modifying the natural environment. • Clear the forest, planting, plough land, sow crops, adding fertilizers….. New landscape • Use a unsuitable farming method in the environment and causes serious consequences • Over-cropping and over-grazing cause soil erosion • Using chemical fertilizers and pesticides gain enormous benefits and environment pollution (Eutrophication)
Impacts on the Environment • Man is increasingly trying various methods of overcoming the physical environment • Modified soil: terrace, wet lowlands drained, coastlands reclaimed, adding chemicals (fertilizers, pesticides, weedicides) • New varieties of plants and animals • Requirement: large input of capital and labour (extremely high cost) • Developed countries can lessen to some extent the influence of physical environment.
