Download - Agri N Rural Devp Notes
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Agri n rural devp
topic is seed production which includes :
• Flowering and pollination
• Hybrid seed production • Genetic purity
• Production factors influencing seed quality
• Specific practices for each crop (vegetables, alfalfa, sunflower, canola)
• Harvesting
• Conditioning
• Enhancement
• Storage
What is seed village?
A village, wherein trained group of fanners are involved in production 'of seeds of various
crops and cater to the needs of themselves, fellow fanners of the village and fanners of
neighboring villages in appropriate time and at affordable cost is called "a seed village".
Concept
Organizing seed production in cluster (or) compact area
Replacing existing local varieties with new high yielding varieties.
Increasing the seed production
To meet the local demand, timely supply and reasonable cost
Self sufficiency and self reliance of the village
Increasing the seed replacement rate
Features
Seed is available at the door steps of farms at an appropriate time
Seed availability at affordable cost even lesser than market price
Increased confidence among the farmers about the quality because of known source of
production
Producer and consumer are mutually benefited
Facilitates fast spread of new cultivars of different kinds
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SEED VILLAGE
Advantages of Seed Village Concept or Compact Area Approach-
1. Solve the problem of isolation. Mainly in cross pollinated crops like maize, sunflowerwhere it required more Isolation distance the problem will be solved by raising a single
variety in a large area.
2. Mechanization is possible from sowing to harvesting
3. Post harvest handling of seed is easy .
4. Because of a single variety, the problem of varietal admixture during processing, drying
will be avoided
5. Seed certification official will cover large area per unit time
6. Totally it reduces the cost of cultivation
7. Seed will be with high genetic, physical purity
Genetic purity refers to the percentage of contamination by seeds or genetic material of
other varieties or species.
The genetic purity of any commercial agricultural product propagated by seed begins with
the purity of the seed planted.
In general, the genetic purity of the seed planted must equal or exceed the final product
purity standard required, as purity generally decreases with each subsequent generation of
propagation.
It is virtually impossible to assure that no off-type plants or pollen is present in the seed
production field and that all handling and conveyance equipment and storage facilities are
completely free of contamination.
As a result, commercial planting seed is seldom 100% pure.
In practice, practical seed genetic purity standards have been established by state seed
laws and by seed certification agencies to ensure that the purchaser receives seed that iswithin certain purity tolerances.
These tolerances are established based on the biology of the species (i.e., self- or cross-
pollinated), the type of variety (i.e., open-pollinated, hybrid, synthetic), and market-
driven standards for final product quality. Earlier generations of seed (e.g., foundation or
registered seed) have stricter standards in order to be able to meet the certified seed purity
criteria.
The main sources of contamination of a seed crop are the prior crop grown in a field,
transfer of pollen from a nearby field, and mixtures during harvesting and handling.
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physical purity of seed refers to the presence and identity of weed seeds, and the
percentage of other materials such as dirt or plant residues. In addition, the germination
capacity of the seed in a standard test must be shown on the label. In some cases, seeds
must also be tested for the presence of seed-borne diseases, and hybridity tests are
conducted to confirm parentage in hybrid seed.
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Dry farming crops are characterized by very low and highly variable and uncertain yields.
Crop failures are quite common. These are mainly due to the following causes.
Inadequate and uneven distribution of rainfall
In general, the rainfall is low and highly variable which results in uncertain crop yields.
Besides its uncertainty, the distribution of rainfall during the crop period is uneven, receiving
high amount of rain, when it is not needed and lack of it when crop needs it.
Late onset and early cessation of rains
Due to late onset of monsoon, the sowing of crop are delayed resulting in poor yields.
Sometimes the rain may cease very early in the season exposing the crop to drought during
flowering and maturity stages which reduces the crop yields considerably
Prolonged Dry spells during the crop period
PROBLEMS OF CROP PRODUCTION IN DRYLAND
Long breaks in the rainy season is an important feature of Indian monsoon. These intervening
dry spells when prolonged during crop period reduces crop growth and yield and when
unduly prolonged crops fail.
Low moisture retention capacity-The crops raised on red soils, and coarse textured soil suffer
due to lack of moisture whenever prolonged dry spells occur due to their low moisture
holding capacity. Loss of rain occurs as runoff due to undulating and sloppy soils.
Low Fertility of Soils-Drylands are not only thirsty, but also hungry too. Soil fertility has to be increased, but there is limited scope for extensive use of chemical fertilizers due to lack of
adequate soil moisture.
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Agro-ecology-The study of the relation of agricultural crops and environment
Eco-farming -It is the potential for introducing mutually reinforcing ecological approaches to
food production. It aims at the maintenance of soil chemically, biologically and physically
the way nature would do it left alone. "Feed the soil, not the plant" is the watch word and
slogan of ecological farming.
Alley Cropping-A farming system in which arable crops are grown in alleys formed by trees
or shrubs, established mainly to hasten soil fertility restoration and enhance soil productivity,
and for shelter.
Agro-forestry-It is a self-sustaining land management system which combines production of
agricultural crops with tree crops and also with livestock simultaneously or sequentially, on
the same unit of land.
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Agro-silvi-pastoral-Systems in which land is managed for the concurrent production of
agricultural and forest crops and for the rearing of domesticated animals. This system is, in
effect a combination of agri-silviculture and the silvi-pastoral system.
Multiple Cropping-Growing two or more crops consecutively or at the same time on the same
field in the same year.Mixed Cropping-Growing of two or more crops simultaneously on the same piece of land,
without any definite row arrangement.
Multi-story/Multi-tier Cropping-It is a system of growing together, crops of different heights
at the same time on the same piece of land and thus using land, water, and space most
efficiently and economically i.e coconut + pepper + pineapple + grass.
Strip Cropping-Growing soil conserving and soil depleting crops in alternate strips running
perpendicular to the slope of the land or to the direction of prevailing winds for the purpose
of reducing erosion.
Intercropping-It refers to growing of two or more generally dissimilar crops simultaneouslyon the same piece of land. Usually the base crop is grown in a distinct row arrangement. The
recommended optimum plant population of the base crop is suitably combined with
appropriate additional plant density of the associated crop, and there is crop intensification in
both time and space dimensions.
Cropping Systems-pattern of crops taken up for a given piece of land, or sequence in which
the crops are cultivated on piece of land over a fixed period and their interaction with farm
resources and other farm enterprises.
Agronomy= Branch of agriculture that deals with field crop production and soil management.
agronomy= Agri = Soil mgt + crop production !!
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AGRO CLIMATIC ZONES K LIYE FOLLOW THIS! its a table in 3 page format
http://www.imdsikkim.gov.in/AGRO.pdf
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Top Factors Affecting Crop Production
Rapid urban development and accompanying development of infrastructure
Cropland area has been lost to degradation because of deforestation and inappropriate
agricultural practices.
Due to environmental degradation and loss of ecosystem components, there would be
reduced yield of food crops. Unsustainable practices in irrigation and production may lead to
increased salinisation of soil, depletion of soil nutrients, and erosion. This, in turn, will cause
lower yields. The productivity of some lands has declined by 50 per cent due to soil erosion
and desertification.
Invasive alien species — pests and diseases — are another threat to food production. Pests and
pathogens have had particularly severe effects on crop yields in the world’s poorest and mostfood insecure region of sub-Saharan Africa. Increased climate extremes may encourage the
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spread of plant diseases, pest outbreaks and weeds
Fisheries — freshwater and marine — supply about 10 per cent of world human calorie intake.
It is estimated that fish contributes up to 180 kcal per day, but these heights are reached only
in a few countries where there is a strong preference for fish or there is a marked lack of
alternative protein foods grown locally. Recommending an increased intake of fish, however,needs to be balanced against concerns of sustainability.
There has been an increasing pressure on the livestock sector to meet the growing demand for
high-value animal protein. Annual meat production is projected to rise to more than 375
million tonnes by 2030 from about 200 tonnes in 1997-98. Various factors are at work in this
increase in demand for livestock products. Mainly, with increased income levels, it is seen
that consumption of animal protein (meat, milk, eggs) increases at the cost of staple foods
(cereals, for example).
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discussing these topics. "meterology" next !
1.Agriculture: definition, meaning and its branches, Agronomy: definition, meaning
and
scope of agronomy. Classification of field crops. Factors affecting on crop production,
Agro
Climatic Zones; Cropping Systems: Definition and types of cropping systems.
Problems of
dry land agriculture; Seed production, seed processing, seed village; Meteorology:
weather parameters, crop-weather advisory; Precision Farming, System of Crop
Intensification, organic farming;
>>Meteorological measurements for weather forecasting and climatology have been carried
out on a regular basis for centuries. However, the data acquired can only be evaluated and
interpreted after having statistically recorded medium-term and long-term atmospheric
conditions.
Nowadays, transport and communications such as ground, air and sea traffic could not be
maintained without these data, which are mainly being collected from measurements and
observations in the atmosphere close to the ground (the Boundary Layer). The main
meteorological parameters in this field are:
Wind speed and direction
Air temperature
Air pressure
Air humidity
Precipitation
Haze and contents of the air
Solar and terrestrial radiation
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Within the atmosphere close to the ground the temporal and spatial characteristics of
radiation values are influenced by the characteristics of the ground surface. The most
influential factors affecting the received radiation at any particular location are:
o Location on the earth
o Date and time
o Precipitation (cloud, fog, rain, snow)
o Constriction of the horizon (field of view)
o Air pollution (aerosols and gasses)
o Albedo
>>To assist the farmer in these changing contexts new strategies and innovative solutions are
urgently required which in turn will require technological support. Hence the agricultural
research system which generates technologies, has to conduct the business of agricultural
research in an innovative way. The World Bank aided National Agricultural InnovationProject (NAIP) has been conceived to pilot this innovation in conducting agricultural
research.
>>VERY IMP !
The Indian National Agricultural Research System (NARS) has to find solutions for the
immediate problems of farming as well as keep its competence in technology development in
the forefront to meet all continuously emerging anticipated and unanticipated problems. Basic
and strategic research and applied research in the frontier areas of agricultural sciences are
the ‘pacemaker’ of technology development. Fully realizing this need, the Government of
India decided to establish a national fund for supporting basic and strategic research with theobjective of building capacity for basic and strategic research for solving agricultural
problems of immediate, long-term and anticipatory nature, building partnership of all
required expertise available in all disciplines and institutions in all over countries and to make
India a global leader in research for development.
The Fund was named as ‘The National Fund for Basic, Strategic and Frontier Application
Research in Agriculture’ (NFBSFARA). With the experience gathered during the 10th and
11th Plan Periods, results obtained and the base created, it was decided by the Indian Council
of Agricultural Research, New Delhi in consultation with the Empowered Committee of the
NFBSFARA that the fund must be given a wider perspective and arena. A strong and
sustainable platform that would help develop a scientific capacity and culture in the extended NARS capable of ensuring continuous flow of knowledge and frontier technology of the best
and appropriate quality for solving problems in agriculture and also provide a source of
science policy for agriculture would be required. Commensurate with this requirement the
name of the Fund was changed to ‘National Agricultural Science Fund’ (NASF) during the
XII Plan.
Objectives
The main objective of the scheme has been to build capacity for basic, strategic and
cutting edge application research in agriculture and address issues which can be solved by
intensive basic and strategic research jointly by team of organizations/ institutions.
Underlying this objective are the following aims:
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Foster research and a research culture that will use and advance the frontiers of scientific
knowledge to effectively meet the present, anticipated and unanticipated problems of
agriculture through various modes and critical investments in research projects.
Build the capability of the National Agricultural Research System through development
of wide partnerships in science through projects. Build a storehouse of advancement of knowledge in science related to agriculture and
awareness of the national importance of basic and strategic research in agriculture.
To provide policy support to the decision makers for use of basic and strategic research in
agriculture.
Organizations of workshop, seminars, conferences etc. to create awareness, prioritization,
scientific popularization and related issues.
>>Precision agriculture (PA) or satellite farming or site specific crop management (SSCM) is
a farming management concept based on observing, measuring and responding to inter and
intra-field variability in crops. Crop variability typically has both a spatial and temporal
component which makes statistical/computational treatments quite involved. The holy grail
of precision agriculture research will be the ability to define a Decision Support System
(DSS) for whole farm management with the goal of optimizing returns on inputs while
preserving resources
The system of crop intensification method of growing food crops provides high yields, on
limited land, despite a much smaller amount of seed for planting. The ‘seeding rate’ is the
amount of seed needed to plant a particular area of land
Generally speaking, the method has the same basic principles, with some variation forindividual crops:
1. plant seeds close together in a ‘nursery’, a bed of loose composted soil.
2. transplant the seedlings into the field after 8 to 15 days of growth.
3. make certain that the field soil is loose, drains well and is thoroughly amended with
compost
4. use a wide spacing of plants (typically 7.5 to 15 plants per square meter)
5. weed the field carefully
6. keep the soil moist, but not over watered; some methods let the field dry periodically
between waterings
7. chemical fertilizer can be used in addition to compost to increase yields further.
Organic farming is a form of agriculture that developed from a desire to improve soil
quality and the environment, and from a strong rejection of the use of synthetic chemicals
and fertilizers in agriculture.
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POVERTY AND ITS ALLEVIATION IS AN IMP TOPIC
THERE IN THE SYLLABUS
>>What are Important Causes of Poverty in India?
In view of the big size and the serious nature of the problem of poverty, it is necessary to find
out its causes.
>>Little Trickle-down Effect:
An important set of factors responsible for this situation is that the beneficial effects of
growth did not reach large masses of the people. The major reasons for this may be identified
as those which kept the poor out of the development process. The emphasis all along since
the Second Plan and until recently has been on the building of the capacity for capital goods.
>>This meant two things:
Investments in capital-intensive projects or less employment generating schemes; and lesser
resource availability for consumption/wage goods, as also for labour intensive industries.
Together these resulted in slower growth in employment or wage-income for the masses and
small growth in the availability of consumption goods. The progress in small and cottage
industries was not sufficient to absorb the backlog of unemployment and the rising labour
force. Other significant factor which prevented the poor from benefitting from growth has
been the widening inequalities of incomes.
In the capital intensive projects the proportion of income going as wages is bound to be low.
But equally important is the unequal distribution of assets, partly helped by the strategy
which places premium on non-wage incomes.
It has enabled the few at the top to corner a large proportion of the national income from year
to year. For this reason even a smal1 rise in per capita income could not reach the poor.
>>Little Strengthening of Poor:
The strategy and the progress made under it could make sense, if it had been accompanied by
large transfers to favour the poor and also the efforts aimed at raising the capabilities of the
poor. Neither of these happened to the extent required to uplift the poor who were below the
poverty line.
The institutional credit and the technology transfers too have remained much less than needed
for expansion and modernisation of their activities. Their earning capabilities to have
remained weak with illiteracy and ill-health rampant among them.
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>>Agronomy and Horticulture Department. Agronomy is the application of plant and soil
science to crop production. Horticulture is the science and art of cultivating fruits, vegetables,
flowers, and ornamental plants
Agronomist Job Duties
Agronomists have varied duties that require them to think critically to solve problems. First
and foremost, agronomists experiment and plan studies to improve crop yields. They study a
farm's crop production in order to discern the best ways to plant, harvest, and cultivate the
plants, regardless of the climate. It is also important for agronomists to develop methods to
control weeds and pests to keep crops disease-free.
Agronomists often use mathematical and analytical skills in conducting their work and
experimentation. Complex data and information that they develop must be worked into a
serviceable format for public consumption. Agronomists relay their information in written
form, making presentations and speeches as well as responding diplomatically to sensitive
issues regarding their findings. Their ultimate goal is to work scientifically to produce thefinest crops, on the most consistent basis that they can, in any situation.
>>SCOPE OF AGRONOMY
Agronomy for Sustainable Development is an international journal for scientific research on
the interactions between cropping systems and other activities in the context of sustainabledevelopment.
Sustainable agriculture, ecological production
Innovation in farming systems
Agriculture and preservation of natural resources
Sustainable land use
Agriculture and global changes
Agroclimatology and modelling
Biogeochemistry of agrosystems
Pollutants in agrosystems
Ecological pest control and biopesticides
Ecological, economical and social impacts of genetic engineering applications
Environmental impact on soil, water, air and biodiversity
Risk assessment for food, ecotoxicology
Food quality, food safety, supply chain management, and geographical indication
Environmental management in agriculture
Decision support systems and companion modelling
Organic farming
Ecological cropping and farming systems
Agricultural production of renewable energies
Genetically modified organisms (GMOs) in cropping systems
Social and economical issues of agricultural changes
Basic Concepts of Agronomy
Agronomy is considered as the mother or primary branch of agriculture. Like agriculture, it is
nothing but an integrated and applied aspect of different disciplines of pure sciences. It hasthree distinct branches:
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Crop Science (mainly field crops)
Soil science
Environmental Science ( that deals with applied aspects)
The central theme of agronomy is of soil-crop-environment relationship.
The core of agronomy is the field of crop plants with the theme of controlling the
environment (micro climate). The nature of agronomy is based on soil-plant- environment
relationship.
Agronomy thus denotes activities on the ground to raise outspread and noble crops to obtain
massive yields.
Scope of Agronomy
Yield maximization with introduction of new cultivars/ HYVsReduced cost of production due to proper crop management
Better water use efficiency due to agronomic knowledge
Special tillage and intercultural operations for better crop growth and maximizing harvesting
index
Appropriate soil fertility management can increase crop yields with lesser use of fertilizer for
increased profit
Reduced post harvest loss due to agronomic knowledge and practices
Intensive cropping patterns and integrated farming systems for sustainable agricultural
growth and increased food production per unit area to feed teeming millions every year.
Basic Principles of Agronomy
Agronomic principles are the ways and means for the better management of soil, plant and
environment for economically maximum returns per unit area for years.
The Basic Principles of agronomy may be listed below:
>Planning programming and executing measures for maximum utilization of resources ( land,
sunshine, rain water, temperature, humidity , winds) and inputs( labor, seeds, capital ,
irrigation water, fertilizer/ manures, farm equipment, marketing facilities etc ) for increased
yield and maximum profits
>Choice of proper crop varieties adaptable to the particular agro-climate, land situation , soil
fertility , season and befitting to the cropping systems
>Proper field management by tillage, preparing field channels and bunds for irrigation and
drainage, checking soil erosion, leveling and adopting other suitable land improvement
practices
>Adoption of multiple cropping and also mixed or intercropping to ensure harvest even under
adverse environmental conditions.
>Choice of quality seeds or seed materials and maintenance of requisite plant density per unit
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area with healthy and uniform seedlings
Proper water management /better water use efficiency
Adoption of adequate plant protection measures/IPM
Adoption of suitable management ractices/intercultural operations
Adoption of suitable method of harvesting of crops as well as suitable post harvesttechnologies
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WE COVERED FIRST POINT IN AGRI SLLABUS OF NABARD
Agriculture: definition, meaning and its branches, Agronomy: definition, meaning and
scope of agronomy. Classification of field crops. Factors affecting on crop production, Agro
Climatic Zones; Cropping Systems: Definition and types of cropping systems. Problems of
dry land agriculture; Seed production, seed processing, seed village; Meteorology:
weather parameters, crop-weather advisory; Precision Farming, System of Crop
Intensification, organic farming.
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Upto this point it covers only 1st point of agriculture syllabus !!!
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NEXT :a) Soil and Water Conservation : Major soil types, soil fertility, fertilisers, soil
erosion, soil conservation, watershed management;
Major types and characteristics of soils in India:
Indian soils may be divided into six major types based on their character and origin:
1. Alluvial soil: Materials deposited by rivers, winds, glaciers and sea waves are calledalluvium and soils made up of alluvium are alluvial soils. In India alluvial soils are mainly
found on the Indo-Ganga Brahmaputra Plains, Coastal Plains and the broad river valleys of
South India. They are also found along the river basins of some plateau and mountain
regions.
In the Indo-Ganga plain two other types of alluvium are found. The old alluviums are clayey
and sticky, have a darker color, contain nodules of lime concretions and are found to lie on
slightly elevated lands. The new alluviums are lighter in color and occur in the deltas and the
flood plains.
In comparison to old alluvial soil, the new alluvial soils are very fertile. The alluvial soil isregarded as the best soil of India for its high fertility and the rich harvest, it gives rice, wheat,
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sugarcane, jute oil-seeds and pulses are the main crops grown on this soil.
2. Laterite and Lateritic soils: Laterite is a kind of clayey rock or soil formed under high
temperature and high rainfall. By further modification laterite is converted into red colored
lateritic soils charged with iron nodules. Laterite and lateritic soils are found in South
Maharashtra, the Western Ghats in Kerala and Karnataka, at places on the Eastern Ghat, insome parts of Assam, Tamil Nadu, Karnataka, and in western West Bengal (particularly in
Birbhum district). These soils are generally infertile. Some plants like tea, coffee, coconut,
areca nut, etc. are grown in this soil.
3. Red Soils: Red soils develop on granite and geneses rocks under low rainfall condition.
The dissemination of red oxides of iron gives the characteristic red color of the soil. These
soils are friable and medium fertile and found mainly in almost whole of Tamil Nadu, South-
eastern Karnataka, North-eastern and South-eastern Madhya Pradesh, Jharkhand the major
parts of Orissa, and the Hills and Plateaus of North-east India. But these have capacity to
grow good crops after taking help of irrigation and fertilizers. Wheat, rice, millets, gram,
pulses, oil-seeds and cotton are cultivated here.
4. Black Soils or Regur soils: The regur or black soils have developed extensively upon the
Lava Plateaus of Maharashtra, Gujarat, Madhya Pradesh mainly Malwa. Black soils have also
developed on gneisses of north Karnataka and north and west of Andhra Pradesh. The regur
is clayey, becomes very sticky when wet. Its special merit lies in its water holding capacity.
These soils are very fertile and contain a high percentage of lime and a moderate amount of
potash. The type of soil is specially suited to the cultivation of cotton and hence sometimes
called ‘black cotton soil.’ Sugarcane, wheat, and groundnut are also cultivated.
5. Desert soil: The soils of Rajasthan, Haryana and the South Punjab are sandy. In the
absence of sufficient wash by rain water soils have become saline and rather unfit for
cultivation. In spite of that cultivation can be carried on with the help of modern irrigation.
Wheat, bajra, groundnut, etc. can be grown in this soil.
6. Mountain soil: Soils are varied in mountains. Alluvium is found at the valley floor, brown
soil, rich in organic matter, in an altitudinal zone lying between about 700-1800 m. Further
up podzol soils, grey in color and acidic in reaction, are found associated with coniferous
vegetation. In the Alpine forest belts the soils are thin and darker in color. This type of soil is
suitable for the cultivation of potatoes, fruits, tea coffee and spices and wheat.
What is soil fertility?Soil fertility is the capacity of soil to support plant growth and the many beneficial processes
that occur in soil. Soil fertility is the combined effect of three major interacting components,
the chemical, physical and biological characteristics of the soil. The physical and chemical
characteristics of soil are far better understood than that of the biological component,
therefore we know quite a lot about the desired chemical and physical status of soils. It is still
difficult to define the desired biological status of soil because soil organisms are so dynamic
and changes occur in much shorter time periods than physical and chemical changes.
>Soil fertility may be defined as the ability of soil to provide all essential plant nutrients in
available forms and in a suitable balance whereas soil productivity is the resultant of several
factors such as soil fertility, good soil management practices availability of water supply andsuitable climate.
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>The soil is a natural medium for plant growth and it supplies nutrients to plants. Some soils
are productive and they support luxuriant growth of plants with very little human effort
whereas others may be unproductive which support almost no useful plant life regardless of
every human effort In order for soil to be productive, it must:
(i) Be easily tillable and fertile
(ii) Contain all essential elements in the forms readily available to plants in sufficient amount,
and
(iii) Physically good to support plants and contain just the right amount of water and air for
proper root growth. The soil must supply these essentials every day in the life of the plant.
>>The mineral elements are taken by plants from soils mostly in the form of ions. Plants
obtain nutrients from the following four devices:
(i) From the soil solutions through roots,
(ii) From exchangeable ions on the surface of clay and humus particles through roots,
(iii) From readily decomposable minerals, and
(iv) Through the leaves.
>>The essentiality of an element is proved by the following criteria:
(a) The element may be considered essential if its exclusion from the nutrient medium
inhibits or drastically reduces the growth and reproduction of plant.
(b) Acute deficiency of the element produces certain well defined disease symptoms which
are not produced by the deficiency of any other element.
(c) Deficiency disease symptoms will disappear if the particular element is supplied before
the living system has been damaged beyond repairs.
Soil Fertility Factors:
Several factors are known to govern the fertility of soil. Some of the important factors are
discussed below:
1. As a result of cropping, a large amount of organic matter and soil minerals are removed
and if the normal cycling of mineral elements is retarded, loss in soil fertility may result.
2. Besides cropping, soil erosion and loss of water also causes tremendous loss of plant
nutrients from the top soil.
Generally, water is lost through leaching, drainage, evapotranspiration and runoff.
>>The following adverse affects are observed due to water loss:
(i) Soil becomes very hard.
(ii) The seed germination percentage decreases.
(iii) The nutrients in the soil leach or evaporate.
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(iv) The root growth retards, so that plants become stunted and, as a result, the yield is
reduced.
(v) Stomata become closed, as a result of which accumulation of gases or metabolic wastes
increases in plant tissues leading to death of the plant.
(vi) The activity of soil-micro organisms decreases.
>>Maintenance of Soil Fertility:
Soil fertility is the most important asset of a nation. Maintenance of soil fertility is an
important aspect of agriculture. The soil fertility problem has been studied in many countries
and scientists have brought to light several facts concerning soil fertility and its maintenance.
>>Soil fertility is of two types;
(a) Permanent fertility:
It is derived from the soil itself. It can be improved, maintained or corrected by soilmanagement practices.
(b) Temporary fertility:
It is acquired by suitable soil management but the response of built up soil fertility is highly
dependent on the degree of permanent fertility which is already there. Several methods are
known for controlling the loss of soil fertility
>>Organic manures improve soil fertility in the following ways:
(i) They modify the physical properties as increase in granulation of the soil and increase in
permeability and moisture holding capacity of soil.
(ii) They provide food for soil microbes and thus enhance microbial activities.
(iii) Decomposition products of organic manures help to bring mineral constituents of soil
into solution.
(iv) They improve physico-chemical properties of soil, such as cation exchange and buffering
action.
Need for Irrigation:
Irrigation is the artificial watering of soil to sustain plant growth. Irrigation has becomenecessary because of the limitation of using natural rainfall as the reliable source of water for
agriculture. It is also difficult to store the rainwater for immediate irrigation purposes.
In India, monsoon is usually erratic; sometimes delayed, sometimes scarce or sometimes in
excess. Through the monsoon season usually lasts for four months, most of the rains occur
only during two months. Therefore, it is very difficult to plan the cropping pattern depending
solely on the rams. The sufficient recharging of ground water is essential for sustainable
farming, but usually this objective is not fulfilled due to unpredictable and fluctuating rains.
The efficient utilization of water resources is essential for better crop production. It includes
the suitability of land and water for irrigation, planning of crops and suitable water
management practices. Water management includes irrigation and drainage.
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The suitable irrigation depends on:
Time of irrigation
Amount of irrigation, and
Efficient method of irrigation
>>Problems of Excess Irrigation:
i. Excess irrigation causes several changes in the soil and plants, resulting in reduced growth
and sometimes even death of plants.
ii. Germinating seeds are sensitive to water logging, since they are totally dependent on the
surrounding soil space for oxygen supply
iii. Yield of cereals is reduced if excess irrigation is given.
iv. Excess water causes injury to the plant due to low oxygen supply to the root system and
accumulation of toxic substances in the soil.
v. Leaching of nitrates and de-nitrification occur which result in nitrogen deficiency.
vi. Permeability of roots decrease due to shortage of oxygen. It results in decreased uptake of
water and nutrient.
>>Soil Fertility – Its Meaning, Causes and Maintenance (With Diagram)
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Read this article to learn about Soil Fertility – Its Meaning, Causes and Maintenance!
Soil fertility may be defined as the ability of soil to provide all essential plant nutrients inavailable forms and in a suitable balance whereas soil productivity is the resultant of several
factors such as soil fertility, good soil management practices availability of water supply and
suitable climate.
The soil is a natural medium for plant growth and it supplies nutrients to plants. Some soils
are productive and they support luxuriant growth of plants with very little human effort
whereas others may be unproductive which support almost no useful plant life regardless of
every human effort In order for soil to be productive, it must:
(i) Be easily tillable and fertile
(ii) Contain all essential elements in the forms readily available to plants in sufficient amount,
and
(iii) Physically good to support plants and contain just the right amount of water and air for
proper root growth. The soil must supply these essentials every day in the life of the plant.
Soil fertility and soil productivity appear to be synonymous but in soil science these two
terms bear different meanings. Soil fertility may be defined as the ability of soil to provide all
essential plant nutrients in available forms and in a suitable balance whereas soil productivity
is the resultant of several factors such as soil fertility, good soil management practices
availability of water supply and suitable climate.
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A soil can be highly fertile, i.e., it has ready supply of nutrients in available form, yet it may
not be highly productive. Water-logged soils may be highly fertile but may not produce good
crop because of the un-favourable physical conditions.
A fertile soil may be highly saline or alkaline which may not be good for agriculture Sandy
soil may be poor in fertility but with the use of fertilizers and water it may be made productive. Soil fertility thus denotes the status of plant nutrients in the soil whereas the soil
productivity is the resultant of various factors influencing crop production. In fact there is no
standard for either fertility or productivity because both depend upon the crops to be grown.
Soil that is productive for potatoes may not necessarily be productive for certain other crops.
Plant Nutrients:Of the 90 or so chemical elements forming the earth’s crust, 16 are known to
be essential for plant growth and reproduction. Seven elements needed in good quantity
(macro nutrients) are hydrogen, oxygen, nitrogen and carbon from air and water and
phosphorus, potassium and calcium from mineral particles in the soil. The other 9 elements
needed only in small amount (micronutrients) are magnesium, sulphur, boron, copper, iron,
manganese, zinc, molybdenum and chlorine.
Jacob and Uexkull have listed cobalt and sodium as essential elements for plant growth. With
the exception of hydrogen, carbon, and oxygen all other inorganic plant requirements are
obtained directly or indirectly from the soil minerals, hence these elements are called mineral
nutrients. Strictly speaking, nitrogen is not a mineral element but it has been included in the
list because it can also be obtained by plants from soil.
The mineral elements are taken by plants from soils mostly in the form of ions. Plants obtain
nutrients from the following four devices:
(i) From the soil solutions through roots,
(ii) From exchangeable ions on the surface of clay and humus particles through roots,
(iii) From readily decomposable minerals, and
(iv) Through the leaves.
The essentiality of an element is proved by the following criteria:
(a) The element may be considered essential if its exclusion from the nutrient mediuminhibits or drastically reduces the growth and reproduction of plant.
(b) Acute deficiency of the element produces certain well defined disease symptoms which
are not produced by the deficiency of any other element.
(c) Deficiency disease symptoms will disappear if the particular element is supplied before
the living system has been damaged beyond repairs.
The capacity of soil to supply the essential elements is a fundamental edaphological problem
In natural habitat the plant matter is returned to ground through decay and unless there is
extensive leaching and percolation the inorganic nutrients become available again for new
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growth Many farm crops are removed from ground in to and the supply of essential elements
thereby becomes depleted.
To replace these elements taken away from ground by crops, the manures or fertilizers are
added. Unless it is done the crop will suffer from deficiencies in the essential elements.
Deficiencies become reflected in the growth of plants in several ways; some may cause areduction in yield as a result of poor plant growth and some may delay maturation of crop a
function that may be very vital to crop yield in the places where the growing season is short
The symptoms of mineral deficiencies may be dwarf, spotted, distorted, curled or wilted
leaves or rotting of the centre of fruits. Different mineral nutrients have certain specific
deficiency symptoms. The physiological roles of various mineral elements in the life of plants
and deficiency symptoms caused by them can be found in any plant physiology book.
Soil Fertility Factors:
Several factors are known to govern the fertility of soil. Some of the important factors arediscussed below:
1. As a result of cropping, a large amount of organic matter and soil minerals are removed
and if the normal cycling of mineral elements is retarded, loss in soil fertility may result.
2. Besides cropping, soil erosion and loss of water also causes tremendous loss of plant
nutrients from the top soil.
Generally, water is lost through leaching, drainage, evapotranspiration and runoff.
The following adverse affects are observed due to water loss:
(i) Soil becomes very hard.
(ii) The seed germination percentage decreases.
(iii) The nutrients in the soil leach or evaporate.
(iv) The root growth retards, so that plants become stunted and, as a result, the yield is
reduced.
(v) Stomata become closed, as a result of which accumulation of gases or metabolic wastes
increases in plant tissues leading to death of the plant.
(vi) The activity of soil-micro organisms decreases.
3. Conversion of organic forms of nitrogen locked in humus into ammonia gas and nitrogen
gas and leaching out of soluble nitrates and nitrites from surface soil greatly affect the
fertility status of soil.
4. Like deficiency, the abundance of certain nutrient elements in soluble form may also be
toxic and even the elements, say alkalies, essential for plant growth may be toxic if present inexcess. Flowering plants do not grow in the soil containing more than 6 per cent NaCl and
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other salts. The elements are not equally toxic and the various species of plants differ in their
susceptibility to different elements.
5. Toxic chemicals and pesticides in soil:
Several agricultural chemicals being used for controlling various diseases and insect pests arehighly toxic and their application adversely affects the soil micro flora and fauna. Prolonged
persistence of these pesticides in soil is bound to lower the soil fertility both directly and
indirectly.
6. Soil reaction:The soils may be alkaline or neutral or acidic in their reaction. Some plants
find acid soil unsuitable for growth and other plants find alkaline ground un-favourable. pH
value of soil solution determines the availability of certain plant nutrients and thus it has
bearing on soil fertility problem. Increase in the acidity of the soil makes mineral salts more
soluble in soil solution and thus salts may become available in concentrations that may be
highly toxic or may damage plants growing in such soils. Janick et al. (1969) have
demonstrated that high concentration of both iron and aluminium may damage plantsgrowing in acid soils.
Maintenance of Soil Fertility:Soil fertility is the most important asset of a nation.
Maintenance of soil fertility is an important aspect of agriculture. The soil fertility problem
has been studied in many countries and scientists have brought to light several factsconcerning soil fertility and its maintenance.
Soil fertility is of two types;
(a) Permanent fertility:
It is derived from the soil itself. It can be improved, maintained or corrected by soil
management practices.
(b) Temporary fertility:
It is acquired by suitable soil management but the response of built up soil fertility is highly
dependent on the degree of permanent fertility which is already there. Several methods are
known for controlling the loss of soil fertility. Here only the important methods are discussed.
1. Application of Organic Manures and Chemical Fertilizers:
Plants absorb water and minerals from the soil, which is essential for growth, flowering, crop
yield, and other vital activities. Soil is a store house for organic and inorganic plant nutrients.
Some soils are rich in organic and humus content and are considered to be fertile and more
productive while others that are deficient in humus and minerals are less productive.
The soil is subjected to a continuous depletion of nutrients due to its continuous use by crops.
This requires the addition of mineral resources. The various soil components are being
removed by living organisms and are returned to the soil by death and decay of organisms. If
the rate of removal or loss of minerals is greater than the rate of addition, the soil will
naturally become less fertile. The minerals of the soils are lost due to crops, leaching or soilerosion.
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The minerals are often removed from the top layer by rainwater. Cultivation of crops
regularly, year after year, makes the soil less productive. In intensive cultivation there are
little chances for the restoration of lost nutrients in the soil until they are supplied from
outside. The leguminous plants, however, compensate the loss of nitrogenous compounds.
Besides this, manure and fertilizers are to be supplemented to restore the fertility of the soil.
The deficiency of mineral nutrients in the soil either can be compensated through organic
manures such as green manuring, compost etc. or it can be supplemented by the application
of chemical fertilizers from outside sources.
A. Organic Manures:
The organic content of the soil which is a good source of plant nutrients contributes most to
the fertility of the soil.
Organic manures improve soil fertility in the following ways:
(i) They modify the physical properties as increase in granulation of the soil and increase in
permeability and moisture holding capacity of soil.
(ii) They provide food for soil microbes and thus enhance microbial activities.
(iii) Decomposition products of organic manures help to bring mineral constituents of soil
into solution.
(iv) They improve physico-chemical properties of soil, such as cation exchange and buffering
action.
Organic manures are of several kinds some of which are discussed below:
(i) Farmyard manures:Solid and liquid excreta as dung and urine of all farm animals are
termed farmyard manures. They are ready made manures and contain nitrogen, phosphorus
and potassium. The farmyard manures of different animals vary greatly in their composition
but they are good for all types of soils and all the crops. Farmyard manure when collected in
field in exposed condition for several months shows considerable loss of fertilizing value as
upon decomposition a considerable amount of ammonia is lost by volatilization.
Therefore, it is important to keep manure protected from weather and manure preparationshould be carried out in trenches of about a metre depth. When the trenches are filled with
dung etc, the surface is covered with a cow dung-earth slurry. In about 3 months the manure
becomes ready for use.
(ii) Compost:Compost manure can be prepared from a variety of refuse materials, such as
straw, sugar cane refuse, rice hulls, forest, litter, weeds, leaves, kitchen wastes. It is prepared
in pits usually 6-8inlong, 1½ to 2inwide and one metre deep. In the pits, 30 cm thick layer of
plant residues moistened with dung, urine and water is formed and then a second layer of
about 30 cm thickness of mixed refuse is spread over it and moistened with slurry. The
operation is repeated until the heap rises to a height of about 50 cm above the ground level.
The top is then covered with a thin layer of moist earth. After three months of decomposition
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the material is well mixed and again covered. After a couple of months the manure is ready
for use.
There are two types of composts:
(а) Farmyard compost which is obtained from animal excreta and plant residues.
(b) Town compost which is obtained by decomposition of kitchen wastes and garbage of
towns and cities. Compost manures are rich in all plant nutrients.
(iii) Green manures:Green manuring is the practice of growing, ploughing and mixing of
green crops with soil to improve soil fertility and productivity. Its effects on soils are similar
to those of farmyard manures. It is cheap and the best method to increase soil fertility as it
can supplement farmyard and other organic manures without involving much cost. Green
manures add nitrogen and organic matter to the soil for the improvement of crop yield.
Through green manuring mobilization of minerals, reduction of organic nutrient losses due toerosion, leaching and percolation, and improvement in physical, chemical and biological
activities of the soil can be achieved. Green manuring also improves soil aeration and
drainage conditions. For green manuring both leguminous and non-leguminous crops are
used. In India, leguminous crops such as sannhemp (sanai), dhaincha, berseem, clover,
Phaseolus mungo, cowpea, are generally used for green manuring.
(iv) Sawdust:Sawdust can be used as bedding material to conserve animal urine or for making
compost. It is a low fertilizing material but it is definitely richer than wheat straw in calcium.
(v) Sewage:In modem system of sanitation, water is used for removal of human excreta and
other wastes.
Sewage consists of two components:
(a) The solid part, called sludge and
(b) The liquid part, called effluent or sewage water.
Sewage is quite rich in several plant nutrients and can be used for fertilizing the crop by
irrigating the soil directly with sewage water but there is a danger for the spread of several
human diseases.
Chemical Fertilizers:
Of the elements known to be essential for plant growth, nitrogen (N), phosphorus (P) and
potassium (K) are required by plants in pretty large amounts, and are therefore, designated as
major ox primary nutrients while calcium, magnesium and sulphur are secondary nutrients.
For acid soils, use of Ca and Mg is necessary. Seven elements iron, manganese, boron,
molybdenum, copper, zinc and chlorine are required in trace amount and hence called micro-
nutrients.
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Nitrogen (N), phosphorus (P) and potassium (K), i.e., the primary plant nutrients are
commonly applied to soils in the form of commercial fertilizers and hence they are often
referred to as fertilizer elements.
Fertilizers and their Composition
>>Chemical fertilizers are classified into the following three group on the basis of materials
supplied:
(i) Nitrogenous fertilizers.(ii) Phosphorus fertilizers, and(iii) Potassium fertilizers.
>>Nitrogenous fertilizers:
Crops usually take nitrogen from the soil in the form of nitrate (NO3-) and ammonium ions
(NH4+).
Nitrogen fertilizers may be divided for convenience into two groups:
(a) Organic nitrogen fertilizers, and
(b) Inorganic nitrogen fertilizers.
(a) Organic nitrogen fertilizers:
Organic materials such as cotton seed meal, guano and fish tank age are nitrogen carriers but
because they supply less than 2% of total nitrogen added in commercial fertilizers, their use is
costly and hence they are not used extensively. Nitrogen of organic fertilizers is releasedslowly by microbial action. They are used as special fertilizers for gardens, lawns and potted
plants.
(b) Inorganic nitrogen fertilizers:
Several inorganic chemicals are used to supply nitrogen to plants.
Phosphorus fertilizers:
Phosphorus has rightly been called ‘master key’ to agriculture as low crop production is due
more often to lack of phosphate than to the deficiency of any other element except nitrogen.
In phosphorus fertilizers this element is present in the form of phosphate or superphosphate
salts and it is available to the plants when it is combined with organic matter or with calcium
and magnesium. Phosphorus is also found in combination with iron and aluminium and is
present in certain rock minerals as apatite.
Superphosphate:It is water soluble fertilizer. It does not affect the soil adversely. It contains
mono-calcium phosphate, di-calcium phosphate and tri-calcium phosphate, gypsum, silica,
iron aluminium sulphate and calcium fluoride and water.
Ammonium phosphate:It is a fertilizer containing both nitrogen and phosphorus. It is rich in
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phosphoric acid content but comparatively low in nitrogen content. Ammonium
superphosphate (NH4H2PO4). Ca3 (PO4)2 (NH4)2 SO4. It is the cheapest fertilizer and is a
mixture of nitrogen and phosphorus fertilizers. It contains nitrogen 3 to 4 per cent and
phosphorus pentaoxide (P2O5) 16 to 18%.
Nitro-phosphate:It is highly hygroscopic. It contains nitrogen 13-18 per cent and phosphorus20 per cent. It is suitable for acid soils.
Bone meal:It is derived from bone. Bone ash and bone char are the bone products. It is
suitable for acidic soils.
Basic slag:Basic slag, a by-product in the manufacture of steel, is one of the cheapest sources
of phosphorus. It is a double compound of silicate and phosphate of lime. It is dark brown in
colour and alkaline in reaction.
Rock phosphate:It occurs in natural deposits. It is light grey in colour. It is a very cheap
fertilizer suitable for acid soils.
>>>Potassium fertilizers:
These fertilizers are soluble in water which means that potassium is readily available to
plants. Total potassium of potassium fertilizers is usually expressed in terms of water soluble
potassium (K) or potash (K2O). Soils of arid and semiarid areas are generally well supplied
with potassium. Acid soils usually need potassium fertilizers more than neutral or alkaline
soils because acid soils develop in the areas of high rainfall that leaches out available
potassium. All potassium fertilizers are physiologically neutral in reaction.
The following are some common potassium fertilizers:
(i) Potassium chloride:It is also called muriate of potash. It contains 48 — 62% K2O. It is also
cheap and neutral in reaction.
(ii) Potassium sulphate:It contains about 50% potash (K2O). It is expensive fertilizer.
(iii) Kainite:It is natural potassium mineral which contains 14 — 20% potassium. It is suitable
for alkaline soils.
(iv) Wood ashes:It is used in the form of ash as a manure. Potassium occurs in the form of potassium carbonate and the percentage of potash is from 2 to 6.5. It is suitable for alkaline
soils.
>>Agriculture Soil Conservation
1. Practice no till farming. With no till farming, crops are allowed to remain rather than being
plowed under at the end of the season. This practice keeps soils anchored in place rather than
having bare ground exposed to wind and water.
2. Use terrace farming. This type of farming uses the topography of the land to slow water
flow through a series of terraces. This manipulation of the water flow prevents it fromgathering speed and washing soil away from farmlands.
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3. Practice contour farming. Contour farming replicates the effects of terrace farming, but on
a smaller scale. Rather than planting crops in straight vertical rows, crops are planted
following the contour of the landscape. Crops planted up and down hillsides create pathways
for water to flow. Crops planted parallel to the land slow the flow of water that prevents soil
erosion.
Home Methods
4. Reduce impervious surfaces. Impervious surfaces like driveways and patios allow
precipitation to flow freely over them. Water flow gains momentum when moving over such
surfaces and can then erode stream banks and lakeshores. A good compromise is to use
paving stones rather than a concrete slab for your patio to allow the water to percolate down
into the soil.
5. Plant a rain garden. A rain garden is a shallow depression in your yard, which will collect
precipitation washing over impervious surfaces. It prevents soil erosion and gives you anopportunity to grow wetland plants.
6. Use a rain barrel. You can place a rain barrel underneath a downspout to collect the water
that runs off of your roof. Your roof, after all, is another impervious surface. You can use the
water you collect for your lawn and garden. In this way, you can conserve water and soil.
Resource Planning
7. Plant windbreaks. Windbreaks prevent soil erosion by slowing the force of the wind over
open ground. You can plant trees or shrubs in your windbreak. In addition to preventing
erosion, these plantings will prevent snow from drifting onto your driveway or into the road.
They can also protect your home from wind damage.
8. Restore wetlands. Wetlands are one of the most effective ways to prevent soil erosion.
Wetlands act as natural sponges, absorbing rainwater and preventing it from carrying the soil
away. They also provide a habitat for birds and other wildlife and help prevent water
pollution.
9. Plant buffer strips along stream banks. Buffer strips help hold stream banks intact during
times of flooding. They also prevent runoff from entering waterways. Buffer strips can
include a mixture of grasses, shrubs, and trees.
10. Re-establish forest cover. The re-establishment of forest cover provides an extensive,
tree-root network that offers a long-term solution to soil erosion. It can function both as a
windbreak and a means to anchor soils in place.
Any of these 10 ways to conserve soil will help protect this important natural resource and
provide a solution for one of the most important environmental issues. Once you begin using
soil conservation methods, you'll no longer look at soil as mere dirt.
>>What is soil erosion?-• When a raindrop hits soil that is not protected by a cover of
vegetation and where there are no roots to bind the soil, it has the impact of a bullet.
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• Soil particles are loosened, washed down the slope of the land and either end up in the
valley or are washed away out to sea by streams and rivers.
• Erosion removes the topsoil first. Once this nutrient-rich layer is gone, few plants will grow
in the soil again.
• Without soil and plants the land becomes desertlike and unable to support life.
>>Causes of soil erosion
Erosion occurs when farming practices are not compatible with the fact that soil can be
washed away or blown away. These practices are:
• Overstocking and overgrazing
• Inappropriate farming techniques such as deep ploughing land 2 or 3 times a year to
produce annual crops
• Lack of crop rotation
• Planting crops down the contour instead of along it.
>Water erosion-Water erosion causes two sets of problems:
• an on-site loss of agricultural potential
• an off -site effect of downstream movement of sediment, causing flooding and the silting up
of reservoirs.
>Sheet erosion-• Soil erosion is characterised by the downslope removal of soil particles
within a thin sheet of water.
• Sheet erosion occurs when the entire surface of a field is gradually eroded in a more or less
uniform way.
• It is a gradual process and it is not immediately obvious that soil is being lost.
>Gully erosion (dongas)-Dongas usually occur near the bottom of slopes and are caused bythe removal of soil and soft rock as a result of concentrated runoff that forms a deep channel
or gully. On steep land, there is often the danger of gullies forming. Water running downhill
cuts a channel deep into the soil and where there is a sudden fall, a gully head forms at the
lower end of the channel and gradually works its way back uphill. As it does so, it deepens
and widens the scar that the gully makes in the hillside. Gully erosion is related to
streambank erosion, in which fast-flowing rivers and streams increasingly cut down their own
banks.
>Rill erosion (channel erosion)-Channel erosion can occur on steep land or on land that
slopes more gently. Because there are always irregularities in a field, water finds hollows in
which to settle and low-lying channels through which to run. As the soil from these channelsis washed away, channels or miniature dongas are formed in the field.
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Focusing efforts at the watershed level provides a comprehensive understanding of local
management needs, and encourages locally led management decisions.
>> The Triple Benefits of a Healthy Watershed
Water is essential for our future. A healthy watershed provides the triple benefits of human,ecological and economic health. The goal of watershed management is to properly balance
and manage this resource.
Ecological Health -A healthy watershed functions as a complete ecological system promoting
the health of all living organisms and landscapes within the watershed. A healthy, intact
watershed minimizes the impacts of flooding and erosion and serves to filter sediments and
contaminants so they do not reach our streams, lakes, and groundwater.
Economic Health-An abundant supply of clean water is essential for a vibrant economy.
Homes, farms, municipalities and businesses all need an ample supply of clean water to
operate effectively. Clean water allows municipalities, businesses, agricultural producers, andindustries to operate more cost effectively, saving money for taxpayers and consumers.
Healthy rivers, lakes, wetlands and natural spaces are foundations for recreation and tourism.
Human Health- Life requires a safe daily supply of water. But water is far more than that:
clean surface and ground water is essential to support our high quality of life and the social
aspects of our communities. Clean rivers, lakes and streams provide many healthy
recreational opportunities including swimming, boating, and fishing.
> History of Watershed Development Program in India
About 60 per cent of total arable land (142 million ha) in India is rain-fed, characterized
by low productivity, low income, low employment with high incidence of poverty and a
bulk of fragile and marginal land (Joshi et al. 2008). Rainfall pattern inthese areas are
highly variable both in terms of total amount and its distribution,
which lead to moisture stress during critical stages of crop production and
makesagriculture production vulnerable to pre and post production risk.
Watersheddevelopment projects in the country has been sponsored and implemented by
Government of India from early 1970s onwards. The journey through the evolutionof
watershed approach evolved in India is shown in Figure-1 (Wani et al. 2005 and 2006).
Various watershed development programs like Drought Prone Area Program(DPAP),
Desert Development Program (DDP), River Valley Project (RVP), NationalWatershedDevelopment Project for Rain-fed Areas (NWDPRA) and IntegratedWasteland
Development Program (IWDP) were launched subsequently in various hydro-ecological
regions, those were consistently being a/ected by water stress and draught like situations.
Entire watershed development program was primarily focused on structural-driven
compartmental approach of soil conservation and rainwater harvesting during 1980s and
before. In spite of putting efforts for maintaining soil conservation practices (example,
contour bunding, pits excavations etc.), farmers used to plow out these practices from
their 1elds. It was felt that a straightjacket top-down approach can not make desired
impact in watersheds and mix up of individual and community based interventions are
essential.
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