Geog 111 agri report 3

8/7/2019 Geog 111 agri report 3

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What is Agriculture?What is Agriculture?

AgricultureAgriculture is the artificial cultivation and processingis the artificial cultivation and processing

ofof animals,animals, plants,plants, fungifungi and other life forms forand other life forms for food, fibersfood, fibers and otherand other

byproducts.byproducts.

INTRODUCTIONINTRODUCTION

Agriculture was based on family farm, providing them food.Agriculture was based on family farm, providing them food.

Today, agriculture is mostly ran by heavy machines.Today, agriculture is mostly ran by heavy machines.

Land can now be cultivated with fewer workers.Land can now be cultivated with fewer workers.

Changes in agricultural technology increased capital requirements.Changes in agricultural technology increased capital requirements.

Rise of AgribusinessRise of Agribusiness

AgribusinessAgribusiness managing the farm as a business entity; primary goal is tomanaging the farm as a business entity; primary goal is toearn money.earn money.

Agriculture production as a global resourceAgriculture production as a global resource because of famine and povertybecause of famine and poverty

all over the world.all over the world.

US as a major food exporter.US as a major food exporter.


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Source: http://en.wikipedia.org/wiki/File:Arable_land_percent_world.pngSource: http://en.wikipedia.org/wiki/File:Arable_land_percent_world.png


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Top 5 worlds meat supply:Top 5 worlds meat supply:

PigPig

CattleCattle

PoultryPoultry LambLamb

GoatGoat

The gap between rich and poor is huge, in terms of kinds andThe gap between rich and poor is huge, in terms of kinds and

consumption of food.consumption of food.

The rich eats more and better food.The rich eats more and better food. Agricultural production in the Third World has been increasing due toAgricultural production in the Third World has been increasing due to

cultivation of new land and improved production.cultivation of new land and improved production.

However, population is also rising.However, population is also rising.

Why does food selfWhy does food self--sufficiency remains a problem?sufficiency remains a problem?

Low Income LevelsLow Income Levels

Rising populationRising population

Uncertain weatherUncertain weather

Rising costs of fuelRising costs of fuel


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The US Agricultural Resource BaseThe US Agricultural Resource Base

America has abundant agricultural land and a relatively smallAmerica has abundant agricultural land and a relatively small

population.population.

One of the most advanced agriculture systemsOne of the most advanced agriculture systems more machines, lessmore machines, less

farmers.farmers.

The US and the World Food SituationThe US and the World Food Situation US agriculture dominates food exports in the world economy.US agriculture dominates food exports in the world economy.

US is a big influence in the world market for agricultural products.US is a big influence in the world market for agricultural products.

The US and the World Food SituationThe US and the World Food Situation

Developed countries overproduce, Developing countriesDeveloped countries overproduce, Developing countries

underproduceunderproduce..


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The Importance of Governmental AgriculturalThe Importance of Governmental Agricultural

PoliciesPolicies

Why does government intervenes in agricultural systems?Why does government intervenes in agricultural systems?

Agriculture is very important to national welfareAgriculture is very important to national welfare source of food andsource of food and

economic prosperity.economic prosperity.

To control prices and production.To control prices and production.

Some policies in the Third WorldSome policies in the Third World Food prices are low to support the poor.Food prices are low to support the poor.

Hurts the farmers.Hurts the farmers.


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Modern Agricultural SystemsModern Agricultural Systems

Mixed CroppingMixed Cropping combine several different crops in a singlecombine several different crops in a singlefarm unit (crops for human consumption and for animal feed).farm unit (crops for human consumption and for animal feed).

Efficient use of landEfficient use of land

MonocultureMonoculture one crop is cultivated repeatedly over a largeone crop is cultivated repeatedly over a largearea.area.

Relies on machines, pesticides, fertilizersRelies on machines, pesticides, fertilizers

Prone to pest infestationProne to pest infestation

Requires large amounts of energyRequires large amounts of energy

Why does Philippines Import Rice?Why does Philippines Import Rice?

Less arable landLess arable land

Prone to typhoons = risksProne to typhoons = risks

Increasing population growthIncreasing population growth


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Components ofComponents of

AgricultureAgriculture


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SoilSoil

Is the uppermost part of the earths surface, w/c has been modified byIs the uppermost part of the earths surface, w/c has been modified by

physical, chemical and biological processes over time.physical, chemical and biological processes over time.Factors that affect soil formationFactors that affect soil formation

ClimateClimate

--affects soil by determining the amount of water that may enter the soilaffects soil by determining the amount of water that may enter the soil

from rainfall and the amount that can be drawn from the surface byfrom rainfall and the amount that can be drawn from the surface by

evaporationevaporation

-- Also determines soil temperature which are important in regulatingAlso determines soil temperature which are important in regulating

chemical reactions in the soil as well as influencing plant growth.chemical reactions in the soil as well as influencing plant growth.

Parent MaterialParent Material

-- is the mineral matter on w/c soil is formed. It affects the soil byis the mineral matter on w/c soil is formed. It affects the soil by

supplying the mineral matter that forms the bulk of the soilsupplying the mineral matter that forms the bulk of the soil

Soil TextureSoil Texture

-- mix of different sizes of particles and on the chemical characteristics ofmix of different sizes of particles and on the chemical characteristics of

the soil.the soil.

TopographyTopography

--influences soil primarily by regulating water movement within and overinfluences soil primarily by regulating water movement within and overthe soil.the soil.


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Biological ActivityBiological Activity

--what the soil the distinctive, living, dynamic substance it is, rather than just anwhat the soil the distinctive, living, dynamic substance it is, rather than just an

accumulation of sterile rock particles.accumulation of sterile rock particles.

-- includes the growth and decay of plants and animals in andincludes the growth and decay of plants and animals in and

above the soil.above the soil. Soil is a four dimensional medium: it varies vertically, in the two horizontal dimensions, andSoil is a four dimensional medium: it varies vertically, in the two horizontal dimensions, and

through time.through time.

In the vertical dimension, most soils exhibit several layers, orIn the vertical dimension, most soils exhibit several layers, orhorizonshorizons, with different, with different

characteristics.characteristics.

The uppermost horizon is called the A Horizon. This layer contains the most organic matter,The uppermost horizon is called the A Horizon. This layer contains the most organic matter,

and it is usually a zone from which dissolved materials are removed by downwardand it is usually a zone from which dissolved materials are removed by downward

percolation of water.percolation of water.

B HorizonB Horizon

C HorizonC Horizon

Below the C Horizon isBelow the C Horizon is unweatheredunweathered parent material.parent material.

oo Soil StructureSoil Structure

--way in which individual soil particles group together in aggregates.way in which individual soil particles group together in aggregates.

Common Soil structures:Common Soil structures:

1.1. PlatyPlaty

2.2. PrismaticPrismatic

3.3. BlockyBlocky

4.4. SpheroidalSpheroidal


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Soil structure is important in determining the water holdingSoil structure is important in determining the water holding

capacity of soil and the speed with which water soaks into andcapacity of soil and the speed with which water soaks into and

through the soil.through the soil.

Soil fertility is defined as the ability of a soil to supply essentialSoil fertility is defined as the ability of a soil to supply essential

nutrients to plants, which is dependent on both the chemical andnutrients to plants, which is dependent on both the chemical and

textual properties of the soil.textual properties of the soil.

Water holding capacity of a soil is primarily determined by itsWater holding capacity of a soil is primarily determined by its

texture.texture.


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WaterWater


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Essential to plant growth and is supplied to crops by rainfall (naturally) or by Irrigation (artificially)Essential to plant growth and is supplied to crops by rainfall (naturally) or by Irrigation (artificially)

IrrigationIrrigation

is an artificial application ofis an artificial application ofwaterwaterto theto the soilsoil..

It is used to assist in the growing ofIt is used to assist in the growing ofagricultural cropsagricultural crops, maintenance of, maintenance oflandscapeslandscapes, and, and revegetationrevegetation of disturbed soilsof disturbed soilsin dry areas and during periods of inadequate rainfall. (Wikipedia)in dry areas and during periods of inadequate rainfall. (Wikipedia)

Types of IrrigationTypes of Irrigation Flood IrrigationFlood Irrigation

-- involves inundating entire fields with water, or allowing water to flow across entire fields.involves inundating entire fields with water, or allowing water to flow across entire fields.

Furrow IrrigationFurrow Irrigation

-- water flows between rows of plants w/c are grown on low ridges. Water is delivered to the furrows by smallwater flows between rows of plants w/c are grown on low ridges. Water is delivered to the furrows by smallditches or in pipes and applied as needed throughout the growing season.ditches or in pipes and applied as needed throughout the growing season.

Sprinkler IrrigationSprinkler Irrigation

--water is pumped under pressure to nozzles and sprayed over land. Nozzles maybe fixed or moved across awater is pumped under pressure to nozzles and sprayed over land. Nozzles maybe fixed or moved across a

field manually or automatically.field manually or automatically. Drip IrrigationDrip Irrigation

-- Each plant has a small pipe that delivers water at a controlled rate directly to the base of the plant. The waterEach plant has a small pipe that delivers water at a controlled rate directly to the base of the plant. The waterdrips out very slowly so that little is lost to evaporation or to seepage. It is an expensive system to install, but it is codrips out very slowly so that little is lost to evaporation or to seepage. It is an expensive system to install, but it is costst--effective in areas where water is scarce.effective in areas where water is scarce.

Irrigated agriculture generally produces high yields as long as water is available. This is because the other environmentalIrrigated agriculture generally produces high yields as long as water is available. This is because the other environmentalcharacteristics of dry lands, plentiful sunshine and warm temperatures, are conducive to crop growth.characteristics of dry lands, plentiful sunshine and warm temperatures, are conducive to crop growth.


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Fertilizers and PesticidesFertilizers and Pesticides

FertilizersFertilizers (or(orfertilisersfertilisers) are substances that supply plant nutrients or amend soil) are substances that supply plant nutrients or amend soil

fertility.fertility. They are the most effective (30They are the most effective (30 --80 per cent increase in yields) (Wikipedia)80 per cent increase in yields) (Wikipedia)

Average yields of grains worldwide have increased over 50 percent in the last 20 years.Average yields of grains worldwide have increased over 50 percent in the last 20 years.

And most of this increase has been due to increases in the use ofAnd most of this increase has been due to increases in the use offertilizersfertilizers..

Nutrients are important for the growth of plants. The three most important nutrientsNutrients are important for the growth of plants. The three most important nutrients

required by plants are:required by plants are:

NitrogenNitrogen

--ultimately derived from the atmosphere. But it is made available to plants by nitrogenultimately derived from the atmosphere. But it is made available to plants by nitrogen--

fixing bacteria. It is the Nutrient that is most often deficient and that is most widelyfixing bacteria. It is the Nutrient that is most often deficient and that is most widely

applied to crops.applied to crops.

Nitrogen Fertilizers are manufactured from natural gas, and the most commonly usedNitrogen Fertilizers are manufactured from natural gas, and the most commonly used

forms are ammonia and urea.forms are ammonia and urea.

Phosphorous is usually present in small quantities in soils, but it is often found in relativelyPhosphorous is usually present in small quantities in soils, but it is often found in relatively

unusable forms.unusable forms.

In soils, Potassium is usually found in larger quantities than phosphorous because it is aIn soils, Potassium is usually found in larger quantities than phosphorous because it is a

more abundant constituent of most rocks. It is also demanded by plants in largemore abundant constituent of most rocks. It is also demanded by plants in large

quantities, and in many areas potassium fertilization is important.quantities, and in many areas potassium fertilization is important.

Organic Fertilizers (primarily manure) have historically been the most important source ofOrganic Fertilizers (primarily manure) have historically been the most important source of

nutrients, especially nitrogen.nutrients, especially nitrogen.


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Pesticide is a general term used to refer to any of a number of chemical agents used toPesticide is a general term used to refer to any of a number of chemical agents used to

control organisms harmful to plants, including insects, fungi and some types of worms.control organisms harmful to plants, including insects, fungi and some types of worms.

Herbicides are used to control weeds.Herbicides are used to control weeds.

There are thousands of different kinds of pesticides and herbicides and the vast majority areThere are thousands of different kinds of pesticides and herbicides and the vast majority are

complex organiccomplex organic compundscompunds manufactured using petroleum as an important raw material.manufactured using petroleum as an important raw material. The large scale use of pesticides in agriculture began in the 1950s.The large scale use of pesticides in agriculture began in the 1950s.

First Widely used insecticides wereFirst Widely used insecticides were organochlorinesorganochlorines such as DDT,such as DDT, aldrinaldrin,, dieldrindieldrin andand

chlordane.chlordane.

In the 1960s and the 1970s these were largely replaced by organophosphates for mostIn the 1960s and the 1970s these were largely replaced by organophosphates for most

uses.uses.

Today Many different types of chemicals are used.Today Many different types of chemicals are used. The dangers of pesticide use have been widely discussed since the early 1960s and the useThe dangers of pesticide use have been widely discussed since the early 1960s and the use

of pesticides has been regulated in many ways.of pesticides has been regulated in many ways.

In general, their use has increased continuously since their introduction.In general, their use has increased continuously since their introduction.


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SeedSeed As a result of selection experiments pioneered by N.E. Borlaug in the 1940s,As a result of selection experiments pioneered by N.E. Borlaug in the 1940s,

advanced varieties of wheat, rice and other staples were first made to the thirdadvanced varieties of wheat, rice and other staples were first made to the third

world farmers in the early 1960s, an era called theworld farmers in the early 1960s, an era called the green revolution.green revolution.

These seeds guaranteed much greater productivity as long as the farmer alsoThese seeds guaranteed much greater productivity as long as the farmer alsoapplied increased amounts of fertilizer, pesticides and/or water.applied increased amounts of fertilizer, pesticides and/or water.

Between 1950 and 1970 per capita grain production increased 30 percent (Brown,Between 1950 and 1970 per capita grain production increased 30 percent (Brown,1980).1980).

One example of the great benefits of seed and fertilizer combinations is found inOne example of the great benefits of seed and fertilizer combinations is found in

Mexico in the decades from 1950 to 1970.Mexico in the decades from 1950 to 1970.

Wheat Production increased from 330,600 tons (300,000Wheat Production increased from 330,600 tons (300,000 tonnestonnes) per year to 2.9) per year to 2.9

million tons (2.6 millionmillion tons (2.6 million tonnestonnes), an eightfold increase.), an eightfold increase.

Corn output increased 250 percent; the bean crop doubled; and the sorghum cropCorn output increased 250 percent; the bean crop doubled; and the sorghum crop

increased 14increased 14--fold.fold.

By the 1970s a leveling trend was seen, and population began to catch up withBy the 1970s a leveling trend was seen, and population began to catch up withthis vastly increased output.this vastly increased output.


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Labor, Machines and EnergyLabor, Machines and Energy

To Grow crops, soil must be tilled, weeds removed and plantsTo Grow crops, soil must be tilled, weeds removed and plantsharvestedharvested

Until the 19Until the 19thth century, Most of this work was done by human andcentury, Most of this work was done by human and

animal labor, using simple tools such as plows and hoes.animal labor, using simple tools such as plows and hoes.

Today, heavy machinery driven by fossil fuels predominates.Today, heavy machinery driven by fossil fuels predominates.

The technological developments in agriculture involving farmThe technological developments in agriculture involving farmmachinery have had their greatest effects in the industrializedmachinery have had their greatest effects in the industrialized

wealthier nations.wealthier nations.

It is estimated that agricultural production per farm workerIt is estimated that agricultural production per farm worker

increased sevenfold between 1850 and 1980 (Rasmussen 1982)increased sevenfold between 1850 and 1980 (Rasmussen 1982)

The amount of petroleum products required to fuel this mechanicalThe amount of petroleum products required to fuel this mechanicaltransformation is enormous. Recent studies that 1974 energy use intransformation is enormous. Recent studies that 1974 energy use in

American Agriculture was 2000 trillion BTU (British Thermal Units),American Agriculture was 2000 trillion BTU (British Thermal Units),

or about 2150 BTU/acre (5300 BTU/ha) (Council on environmentalor about 2150 BTU/acre (5300 BTU/ha) (Council on environmental

quality, 1981b).quality, 1981b).


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GENETICALLY MODIFIEDGENETICALLY MODIFIED

FOODSFOODS TheyThey are foods derived from genetically modifiedare foods derived from genetically modified

organisms. Genetically modified organisms have hadorganisms. Genetically modified organisms have had

specific changes introduced into their DNA by geneticspecific changes introduced into their DNA by genetic

engineering/manipulation techniques. Theseengineering/manipulation techniques. These

techniques are much more precisetechniques are much more precise than mutagenesisthan mutagenesis

(mutation breeding) where an organism is exposed to(mutation breeding) where an organism is exposed to

radiation or chemicals to create a nonradiation or chemicals to create a non--specific butspecific but

stable change. Other techniques by which humansstable change. Other techniques by which humansmodify food organisms include selective breeding, andmodify food organisms include selective breeding, and

somaclonalsomaclonal variation.variation.


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Methods on GeneticMethods on Genetic

Ma

nipula

tionMa

nipula

tion1.1. Genetic modification involves the insertion or deletion of genes. InGenetic modification involves the insertion or deletion of genes. In

the process ofthe process of cisgenesiscisgenesis, genes are artificially transferred between, genes are artificially transferred between

organisms that could be conventionally bred.organisms that could be conventionally bred.

2. In the process of2. In the process of transgenesistransgenesis, genes from a different species are, genes from a different species areinserted, which is a form of horizontal gene transfer. In nature thisinserted, which is a form of horizontal gene transfer. In nature this

can occur when exogenous DNA penetrates the cell membrane forcan occur when exogenous DNA penetrates the cell membrane for

any reason.any reason.

3.To do this artificially may require transferring genes as part of an3.To do this artificially may require transferring genes as part of an

attenuated virus genome or physically inserting the extra DNA intoattenuated virus genome or physically inserting the extra DNA into

the nucleus of the intended host using a micro syringe, or as athe nucleus of the intended host using a micro syringe, or as a

coating on goldcoating on gold nanoparticlesnanoparticles fired from a gene gun.fired from a gene gun.

4. However, other methods exploit natural forms of gene transfer, such4. However, other methods exploit natural forms of gene transfer, such

as the ability ofas the ability of AgrobacteriumAgrobacterium to transfer genetic material to plants.to transfer genetic material to plants.


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Common Genetically Modified CropsCommon Genetically Modified Crops


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Definition:Definition:

ErosionErosion-- the process of weathering and transport of solids (in our report as a form ofthe process of weathering and transport of solids (in our report as a form of

soil) in the natural environment or their source and deposits them elsewhere. It usuallysoil) in the natural environment or their source and deposits them elsewhere. It usuallyoccurs due to transport by wind, water, or ice; by downoccurs due to transport by wind, water, or ice; by down--slope creep of soil and otherslope creep of soil and other

material under the force of gravity; or by living organisms, such as burrowing animals,material under the force of gravity; or by living organisms, such as burrowing animals,

in the case ofin the case of bioerosionbioerosion..

It is a Natural Process.It is a Natural Process.

QUESTION:QUESTION:

Why does it became a problem regarding Agriculture?Why does it became a problem regarding Agriculture?

Answer: It is because of us! Human activities (such as human land use, especiallyAnswer: It is because of us! Human activities (such as human land use, especially

industrial agriculture, deforestation, and urban sprawl) causes it to occur MUCHindustrial agriculture, deforestation, and urban sprawl) causes it to occur MUCH

FASTER than under natural conditions. That causes problems such as these:FASTER than under natural conditions. That causes problems such as these:

DID YOU KNOWDID YOU KNOW

* Annual soil loss in South Africa is estimated at 300* Annual soil loss in South Africa is estimated at 300 -- 400 million tons, nearly three tons for400 million tons, nearly three tons for

each hectare of land.each hectare of land.

* For every ton of maize, wheat, sugar or other agricultural crop produced, South Africa loses* For every ton of maize, wheat, sugar or other agricultural crop produced, South Africa loses

an average of 20 tons of soil.an average of 20 tons of soil.

* The FAO (Food and Agriculture Organization, a branch of United Nations) estimates that the* The FAO (Food and Agriculture Organization, a branch of United Nations) estimates that the

global loss of productive land through erosion is 5global loss of productive land through erosion is 5--7 million ha/year.7 million ha/year.


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Causes ofSoil ErosionCauses ofSoil Erosion Wind and water are the main agents of soil erosion. The amount of soil they can carryWind and water are the main agents of soil erosion. The amount of soil they can carry

away is influenced by two related factors:away is influenced by two related factors:

1. speed1. speed -- the faster either moves, the more soil it can erode;the faster either moves, the more soil it can erode;

2. plant cover2. plant cover -- plants protect the soil and in their absence wind and water can do much moreplants protect the soil and in their absence wind and water can do much more

damagedamage

Physical ProcessPhysical Process

1.1. OVERLAND FLOW (RUNOFF)OVERLAND FLOW (RUNOFF)

-- water flow that occurs when soil is infiltrated to full capacity and excess water fromwater flow that occurs when soil is infiltrated to full capacity and excess water fromrain, melt water, or other sources flows over the land. This is a major component of therain, melt water, or other sources flows over the land. This is a major component of the

water cycle Runoff that occurs on surfaces before reaching a channel is also called awater cycle Runoff that occurs on surfaces before reaching a channel is also called a

nonpoint source.nonpoint source.

DID YOU KNOW:

A watershed produces runoff that drains to a

common point and when runoff flows along

the ground, it can pick up soil contaminants

including, but not limited to petroleum,

pesticides, or fertilizers that become discharge

or nonpoint source pollution.


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2. Wind Erosion (Aeolian Process)2. Wind Erosion (Aeolian Process)

-- processes pertain to the activity of the winds and more specifically, to the winds' ability toprocesses pertain to the activity of the winds and more specifically, to the winds' ability toshape the surface of the Earth. Winds may erode, transport, and deposit materials, andshape the surface of the Earth. Winds may erode, transport, and deposit materials, andare effective agents in regions with sparse vegetation and a large supply ofare effective agents in regions with sparse vegetation and a large supply of

unconsolidated sedimentsunconsolidated sediments Wind erodes the Earth's surface by deflation (the removal of loose, fineWind erodes the Earth's surface by deflation (the removal of loose, fine--grainedgrained

particles), by the turbulent eddy action of the wind and by abrasion.particles), by the turbulent eddy action of the wind and by abrasion.

There are factors that Influence Wind Erosion.There are factors that Influence Wind Erosion. VegetationVegetation. Vegetation slows the wind at the soil level, retarding erosion. Roots bind the. Vegetation slows the wind at the soil level, retarding erosion. Roots bind the

soil, further retarding erosion. Lack of vegetation (ground cover) enhances wind erosion.soil, further retarding erosion. Lack of vegetation (ground cover) enhances wind erosion.

Soil moistureSoil moisture. Surface tension by water in moist soil exceeds the wind force on surface. Surface tension by water in moist soil exceeds the wind force on surface

particle. Wind cannot erode moist soil. Soil with a moisture content of only 1% is veryparticle. Wind cannot erode moist soil. Soil with a moisture content of only 1% is verydifficult to erode.difficult to erode.

StructureStructure of the surface. Organic material, iron, and free aluminum at the surfaceof the surface. Organic material, iron, and free aluminum at the surfacereduces erosion. Sodium or salt at the surface leads to dust at the surface, enhancingreduces erosion. Sodium or salt at the surface leads to dust at the surface, enhancingerosion.erosion.

State of the soil surfaceState of the soil surface. Desert pavement, a layer of pebbles covering the surface, plus. Desert pavement, a layer of pebbles covering the surface, plusdesert varnish on the pebbles, a thin layer of clay with iron and manganese oxidesdesert varnish on the pebbles, a thin layer of clay with iron and manganese oxides

produced by bacteria at the surface, strongly inhibits erosion. Driving on the surfaceproduced by bacteria at the surface, strongly inhibits erosion. Driving on the surfacedestroys the protection leading to rapid erosion.destroys the protection leading to rapid erosion.

StreambankStreambank erosionerosion-- a process that leads to a disproportionate sediment supply, streama process that leads to a disproportionate sediment supply, streamchannel instability, land loss, habitat loss and other adverse effects.channel instability, land loss, habitat loss and other adverse effects. StreambankStreambank erosionerosionprocesses, although complex, are driven by two major components: stream bankprocesses, although complex, are driven by two major components: stream bankcharacteristics (characteristics (erodibilityerodibility) and hydraulic/gravitational forces.) and hydraulic/gravitational forces.


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THE IMPORTANCE OF PLANTS/CROPSTHE IMPORTANCE OF PLANTS/CROPSPlants provide protective cover on the landPlants provide protective cover on the land andpreventandprevent soil erosion for the followingsoil erosion for the following

reasons:reasons:

They slow down water as it flows over the land (runoff) and this allows much of the rainThey slow down water as it flows over the land (runoff) and this allows much of the rainto soak into the ground;to soak into the ground;

Their roots hold the soil in position and prevent it from being washed awayTheir roots hold the soil in position and prevent it from being washed away

They break the impact of a raindrop before it hits the soil, thus reducing its ability toThey break the impact of a raindrop before it hits the soil, thus reducing its ability toerode;erode;

Those in wetlands and on the banks of rivers are of particular importance as they slowThose in wetlands and on the banks of rivers are of particular importance as they slowdown the flow of the water and their roots bind the soil, thus preventing erosion.down the flow of the water and their roots bind the soil, thus preventing erosion.

ECONOMICS of EROSIONECONOMICS of EROSION There are countries that experience overcrowding. This resulted in severe erosion. AsThere are countries that experience overcrowding. This resulted in severe erosion. As

the land became increasingly degraded and thus less productive, subsistence farmersthe land became increasingly degraded and thus less productive, subsistence farmerswere forced to further overuse the land. The intensive agriculture and overgrazing thatwere forced to further overuse the land. The intensive agriculture and overgrazing thatfollowed caused greater degradation. Soil erosion can be seen as both a symptom offollowed caused greater degradation. Soil erosion can be seen as both a symptom ofunderdevelopment and as a cause of underdevelopment. A reduced ability to produce,underdevelopment and as a cause of underdevelopment. A reduced ability to produce,invest one's profit and increase productivity, contributes to increasing poverty, and caninvest one's profit and increase productivity, contributes to increasing poverty, and canlead to desertification, drought, floods, and famine.lead to desertification, drought, floods, and famine.

On commercial farm lands, overstocking, monoOn commercial farm lands, overstocking, mono--cropping, and thecropping, and the ploughingploughing of marginalof marginallands unsuitable for cultivation has led to soil erosion and desertification. Frequentlylands unsuitable for cultivation has led to soil erosion and desertification. Frequentlythese practices have been unwittingly encouraged by the state offering subsidies whichthese practices have been unwittingly encouraged by the state offering subsidies whichmade it profitable to exploit the land in the shortmade it profitable to exploit the land in the short--term.term.


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CONSERVATION TECHNIQUESCONSERVATION TECHNIQUES

The use of contour plowing and wind breaks;The use of contour plowing and wind breaks;

Leaving unplowed grass strips between plowed land;Leaving unplowed grass strips between plowed land;

Making sure that there are always plants growing on the soil, and that the soil is rich inMaking sure that there are always plants growing on the soil, and that the soil is rich inhumus (decaying plant and animal remains). This organic matter is the "glue" that binds thehumus (decaying plant and animal remains). This organic matter is the "glue" that binds thesoil particles together and plays an important part in preventing erosion;soil particles together and plays an important part in preventing erosion;

Avoiding overgrazing and the overAvoiding overgrazing and the over--use of crop landsuse of crop lands

By allowing indigenous plants to grow along the river banks instead of plowing and plantingBy allowing indigenous plants to grow along the river banks instead of plowing and plantingcrops right up to the water's edge;crops right up to the water's edge;

Encouraging biological diversity by planting several different types of plants togetherEncouraging biological diversity by planting several different types of plants together Conservation of wetlandsConservation of wetlands

The use of contour plowing and wind breaks;The use of contour plowing and wind breaks;

Leaving unplowed grass strips between plowed land;Leaving unplowed grass strips between plowed land;

Making sure that there are always plants growing on the soil, and that the soil is rich inMaking sure that there are always plants growing on the soil, and that the soil is rich inhumus (decaying plant and animal remains). This organic matter is the "glue" that binds thehumus (decaying plant and animal remains). This organic matter is the "glue" that binds thesoil particles together and plays an important part in preventing erosion;soil particles together and plays an important part in preventing erosion;

Avoiding overgrazing and the overAvoiding overgrazing and the over--use of crop landsuse of crop lands

By allowing indigenous plants to grow along the river banks instead of plowing and plantingBy allowing indigenous plants to grow along the river banks instead of plowing and plantingcrops right up to the water's edge;crops right up to the water's edge;

Encouraging biological diversity by planting several different types of plants togetherEncouraging biological diversity by planting several different types of plants together

Conservation of wetlandsConservation of wetlands


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AGRICULTURALLAND CONVERSIONAGRICULTURALLAND CONVERSION The amount of land used on which crops are planted in any given year is a small fraction ofThe amount of land used on which crops are planted in any given year is a small fraction of

the available agricultural landthe available agricultural land

Cropland increases when new land is cleared or irrigation water is made available while itCropland increases when new land is cleared or irrigation water is made available while itdecreases when land is converted for other uses or lost from agricultural uses as a result ofdecreases when land is converted for other uses or lost from agricultural uses as a result oferosion,erosion, salinizationsalinization or other degradation processesor other degradation processes

Agricultural land is usually used not for crops due to urban growth, water resourceAgricultural land is usually used not for crops due to urban growth, water resourcedevelopment, changing farm economies and degradationdevelopment, changing farm economies and degradation

Once transformed to residential, commercial, industrial or transportation, there is no turningOnce transformed to residential, commercial, industrial or transportation, there is no turningbackback

URBANIZATIONURBANIZATION Worldwide phenomenonWorldwide phenomenon

The question of whether these losses constitute a debate go aroundThe question of whether these losses constitute a debate go around

What are the expected and future demands for farmlandWhat are the expected and future demands for farmland

Can these demands be met by the available land plus new land that may be broughtCan these demands be met by the available land plus new land that may be broughtinto production?into production?

It is expected that future demand for farmland will increase tremendously however there isIt is expected that future demand for farmland will increase tremendously however there isenough to compensate but much of the reserve is in parts of the world where it is notenough to compensate but much of the reserve is in parts of the world where it is notneeded and most of the available are of low qualityneeded and most of the available are of low quality


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PRESERVATIONPRESERVATION

Tax based on use as opposed to market valueTax based on use as opposed to market value

Establishment of agricultural districtsEstablishment of agricultural districts

Members get tax advantage and various measures are used to restrict or preventMembers get tax advantage and various measures are used to restrict or prevent

conversion of farmlandconversion of farmland

SUSTAINABLE AGRICULTURAL MOVEMENTSUSTAINABLE AGRICULTURAL MOVEMENT

We cannot continue the practices that prevailed during the 1960We cannot continue the practices that prevailed during the 1960--19701970

Promotion of agricultural practices that can be continued indefinitely with no longPromotion of agricultural practices that can be continued indefinitely with no long--termterm

damage aka sustainable agriculturedamage aka sustainable agriculture

First research was on documentation of the long term effects of erosion on soilFirst research was on documentation of the long term effects of erosion on soil

productivityproductivity

Results are now part of the Second Resource Conservation Act AppraisalResults are now part of the Second Resource Conservation Act Appraisal

Second research was on examination of groundwater contamination by agriculturalSecond research was on examination of groundwater contamination by agricultural

chemicalschemicals

Proved its significance and presence while confirming that pesticides would degrade theProved its significance and presence while confirming that pesticides would degrade the

quality of groundwaterquality of groundwater


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Food ProductionFood ProductionFood safety begins with the suppliers of agricultural inputs to farmers and thoseinvolved in food production, since materials such as pesticides and veterinary drugspose different risks and therefore require specific attention.

Agricultural inputs, such as pesticides, fertilizers and veterinary drugs may lead tounsafe levels of these chemicals in the food supply, for instance in red meat andpoultry products, farmed fish and agricultural crops.

U.S agriculture dominates food exports in world economy.

American agriculture feeds many more people than live in the united states,

and there is potential for greater food export.

In the early 1970s increasing world demand for grain and government policies

favouring exports stimulated farmers to increase production.

Bumper harvest in the late 1970s kept prices down, while inflation continued to

force costs and interest rates up.


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In the midIn the mid--1980s this decline in profitability, coupled with1980s this decline in profitability, coupled with

government policies aimed at reducing production, led to agovernment policies aimed at reducing production, led to a

substantial decline in area harvested, with associated productionsubstantial decline in area harvested, with associated production

declines.declines. AMERICAN AGRICULTUREAMERICAN AGRICULTURE

WORLD AGRICULTURE MARKETSWORLD AGRICULTURE MARKETS


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Food Production IndexFood Production Index. Per capita food production is declining in. Per capita food production is declining in

Africa, but it is increasing steadily in the world as a whole. ThisAfrica, but it is increasing steadily in the world as a whole. This

graphic shows the net food production per capita (PIN base 1989graphic shows the net food production per capita (PIN base 1989--

1991) for Africa and for the world for the time period 1961 to 2001.1991) for Africa and for the world for the time period 1961 to 2001. International commodity pricesInternational commodity prices are used, to calculate the totalare used, to calculate the total

value of each commodity produced by each country andvalue of each commodity produced by each country and

subsequently used in the ranking of commodities and countries.subsequently used in the ranking of commodities and countries.

They are applied in order to avoid the use of exchange rates forThey are applied in order to avoid the use of exchange rates for

obtaining continental and world aggregates, and also to improveobtaining continental and world aggregates, and also to improve

and facilitate international comparative analysis of productivity atand facilitate international comparative analysis of productivity atthe national level.the national level.


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CONCLUSIONCONCLUSION

Debate continues on the future of world agricultureDebate continues on the future of world agriculture

SelfSelf--sufficiency in food production is far from realitysufficiency in food production is far from reality

Ecologists now consider largeEcologists now consider large--scale epidemics and diescale epidemics and die--offs to makeoffs to make

the human population return to a stable sizethe human population return to a stable size

A proposed solution is furtherA proposed solution is further transferaltransferal of mechanized agriculture toof mechanized agriculture toless affluent countries accompanied by massive industrializationless affluent countries accompanied by massive industrialization

Concerns for future agricultural resource development revolveConcerns for future agricultural resource development revolve

around energy efficiency, pesticide use and soil erosionaround energy efficiency, pesticide use and soil erosion

Documents

Geog 111 agri report 3