Intensified Agriculture and its Merits and Demerits
-
Upload
sadia-rahat -
Category
Environment
-
view
235 -
download
6
Transcript of Intensified Agriculture and its Merits and Demerits
3/18/2015
History of agriculture
History of agriculture
• GOOD we had food to survive
• Agriculture was too much labor intensive then came a revolution by change in machinery
• Result
• Agricultural productivity soared
Variety of food
Made available
Ecnomicconditions got
better
Living standards increased
Populations increased
Need of cultivating
more land for agriculture
• So more and more land was cleared to increase agriculture.
• But the rate was not high as the population was not too much.
This brought newer technologies with It
World population grew from 1.6 to > 7 BILLION
Agriculture which was on 7% land in 1700 covered > 40% land area now
The world needs to produce more food than ever before
Industrializaiton
Post-Industrializaiton
Need to intensify agriculture
Obligation for farmingIntensify agricultural
production
To produce more crop
and livestock
With less land and
water and small carbon
foot print
Land, water and
resources
b/w agriculture, industry and urbanization
Through large scale
commercial farming
Harsh competition for scarcer
What is agricultural intensification?
Just another name for modern industrial farming
K. Marx
• “the concentration of capital upon the same plot ratherthan its distribution among several adjoining pieces” of land (K. Marx and F. Engels, Soch., 2nd ed., vol. 25, part 2, p. 227)
Lenin pointed out that
• intensification of agriculture is “not some accidental,local, casual phenomenon, but one that is common to allcivilized countries” (Poln. sobr.soch., 5th ed.,vol. 27, p. 168).
Agriculture intensification may occur as a result of :
Increase in the gross
output in fixed proportions due to inputs
expanding proportionately, without
technological changes
Technical progress that raises
land productivity
shift towards more valuable
outputs
Agriculture intensification
is based on:
protectingplant mechanization
in
agriculture
and animal
husbandry
developingirrigation and land
Replacing
low-yield plantingsby high-yield
large
complexes
and factories for
agricultural products
extensive
use of automation
andelectronics
developingintensive
cultivatedand
technicalcrops
Economics of
agriculture
Increasing
mineral and organic fertilizer
Green revolution
• Agriculture intensification came to be known as green revolution
• The Green Revolution was essentially a package of inputs (fertilizer, high yielding seed varieties, pesticides, mechanization etc.) which were designed to lead
to agricultural intensification
•
Green Revolution
• Credit of green revolution is
attributed to NORMAN BORLAUG
• Spread worldwide in the 1950 and 1960
• The plants produced were high yield varieties
Impacts of green revolution
Fertilizers made GR possible – HYV produced now
cannot grow successfully without the help of fertilizers
GR brought irrigation techniques – now water can be stored and Send to drier areas putting more land into
agriculture
Pesticides were used to protect the plants
Tractors and other modern techniques were employed along with
Production of genetically modified plants resistant to environmental stress
Green Revolution has forever changed the way agriculture is conducted
worldwide, benefiting the people of many nations in
need of increased food production.
significance
• Agricultural intensification itself is usually conceived of as a positive process; something that agricultural systems should be encouraged towards.
• However, there may be negative effects of intensification - both in terms of the quantity of livelihoods, and the quality of those livelihoods
• while there may be negative effects on the sustainability (environmental, economic etc.) of those livelihoods.
Merits and Demerits of Intensified Agriculture
Merits of intensified agriculture
1. Increased level of macro nutrients in soil
2. Increased level of Plant Production
3. Increased organic matter content in soil
4. Decreased land use pressure
5. Affordable food outputs
Appropriate application of chemical
fertilizers, increased the N, P, and K
nutrients in the soil, resulting in enhanced
soil quality.
Increased level of macro nutrients in soil
Wheat
RiceMaize
Intensified agriculture has also increased the level of plant production by introducing a
number of faster growing HYV’s ( High Yielding Variety) allow an
extra crop to be grown every year.
Increased level of Plant Production
Increased organic matter content in soil
Intensified agriculture has also increased the level of plant production
which ultimately increases the amount of crop residues that can be returned to the
soil to enhance soil organic matter content.
Crop residue provides:
Soil cover
Reduce soil erosion
Maintain the soil organic matter content
Increases the soil organic matter content
Decreased land use pressure
• Agricultural activities has been intensified mostly on the more productive, relatively level soils,
where risk from erosion are not too high.
• So, the need for expanding onto more fragile lands has been minimized.
• It preserves the soil quality and other related environmental aspects.
With the introduction of intensive farming, farm products such as vegetables, fruits, and poultry
products have become less expensive.
Affordable food outputs
Merits in Pakistan's perspective
• Intensified agriculture leads to a greater, grain and rice production
in Pakistan.
• Multiple cropping would increase gross national product (GNP) of
country.
Pakistan become food self-sufficient and even make modest exports
by late 1980s.
Per capita caloric intake increases by 20% from 1980s-2000s.
DEMERITS OF INTENSIFIED AGRICULTURE
Demerits
• Micronutrient deficiencies
• Increased soil acidification
• Excessive nutrients as pollutants
• Salinization
• Role of pesticides & insecticides
• Role of herbicides
• Unhealthy diet
• Plant diseases
• Reduce biodiversity
• Concentrated animal-feeding operations
Micronutrients removed in the bumper harvests are usually not replaced by
standard N-P-K fertilizers, so micronutrients deficiencies may appear, decreasing the
soil quality.
Micronutrient deficiencies
Intensified agriculture also come-up with heavy use of nitrogen fertilizers,
may leads to increased soil acidification, resulting in decreased
soil quality.
Increased soil acidification
In intensive agricultural activities, N and P usually
applied in the quantities, far in excess of plants uptake.
When these nutrients level built-up in soil, the excessive
nutrients act as pollutants and becomes a part of runoff,
drainage water.
Excessive nutrients as pollutants
Salinization
All irrigation water contains dissolved salts derived as it
passed over and through the land, and rain water also
contains some salts.These salt get deposited into the soil, decreasing the soil quality
and making it unfit for agricultural activities.
Role of pesticides & insecticides
Insecticides and pesticides used in
intensified agricultural activities adversely affect the
soil quality.
These broad spectrum
organochemicalsthreatened the
biological integrity of soil ecosystem.
Some soil treated decades ago with high
level copper and arsenic containing insecticides , still
contain toxic level of these chemicals
Persistent and relatively mobile herbicides in soil have created major
water pollution problem.Intensive use of herbicides may leads to reduce bio-diversity and resilience of the above and below ground soil
communities.
Role of herbicides
Unhealthy diet
Intensified agricultural activities have focused primarily on cereal crops, provides
about half of world’s calories.Less attention has been paid to the pulses (beans, peas etc.), fruits and vegetables. It
creates health problems, as leafy vegetables rich in proteins, micro-nutrients
and essential vitamins.
Monoculture system usually results in a decline in biological productivity mainly because of:
Build-up of pathogensAllelochemicals
Micronutrient deficiency
Plant diseases
Reduce Biodiversity
Chemical intensive, monoculture system results in:
Reduced genetic diversity within crops
Reduced bio-diversity of soil microorganism
Reduced bio-diversity of soil macro-organism
Nitrogen
Phosphorous
Pathogens
Growth accelerating hormones
Antibiotics
In concentrated animal feeding operations (CAFOs), they remove plant
products from wide areas and concentrate them into a production
factory.
Factory waste often pollute the surrounding soil and water systems with
N, P, pathogens, growth accelerating hormones and antibiotics.
Concentrated animal-feeding operations
Plant biodiversity and agriculture intensification
Genetically Modified Crops
• Different new crop varieties have been introduced due to advancement in agriculture (Intensified agriculture).These are formed by inducing some modifications in the genetic material of existing crops varieties.
3/18/2015
Properties of GMCs
High yield crops
Better response to fertilizers
Greater grain size
3/18/2015
Cold resistance
Pest resistance
High starch
Herbicides resistance3/18/2015
Polyester gene addition
Improved sweetness
Improved eating quality
Better taste
3/18/2015
3/18/2015
3/18/2015
GMCs use in the world2010 2011 2012 GMCs
USA 66.8 69 69.5 Maize,Soyabean,cotton, Papaya, Squash, Sugarbeet
Brazil 25.4 30.3 36.6 Soyabeen , Maize Cotton
Argentina 22.9 23.7 23.9 Soyabeen , Maize Cotton
Canada 8.8 10.4 11.6 Canola,Maize,Soyabean, Sugarbeat
India 9.4 10.6 10.8 Cotton
China 3.5 3.9 4 Cotton, papaya, poplar tomato, sweet pepper.
3/18/2015
• After World War II, when human populationrapidly increased, the intensified agricultureprovided the food security for this boom inpopulation.This proved wrong the predictionsof many experts about starvation of humansand ultimately death.
3/18/2015
3/18/2015
World Scenario
3/18/2015
On average, across all
crops grown in the US.
over 90% of the varieties
grown 100 years ago are
no longer in commercial
production or maintained
in major seed storage
facilities
In the Philippines, where
small farmers once
cultivated thousands of
traditional rice varieties,
just two Green
Revolution varieties
occupied 98% of the
entire rice growing area
in the mid-1980s.
Before intensification of agriculture in China, farmers were growing 10,000 varieties of wheat.
Today, 90% of these varieties have disappeared, with only a handful of high yielding wheat variety.
3/18/2015
• According to the U.N. Food and Agriculture Organization, approximately 75 percent of the earth’s plant genetic resources are extinct, with another third of plant biodiversity expected to disappear by 2050.
• Crop genetic resources are being wiped out at the rate of 1-2% every year.
• Tropical forests are falling at a rate of just under 1% per annum.
3/18/2015
3/18/2015
Extinct plants species
• Pouteria stenophylla
• Galapagos Amaranth
• Myrcia skeldingii
3/18/2015
Cont:
• Indian Monocarp Palm
• Yunnan Malva
• Pallasana Spurge
3/18/2015
3/18/2015
Some endangered medicinal plants Sr:No Plants name Medicinal use
1. Blood root plant Treatment of skin disorders and cancer
3. Ginseng root as a soothing agent for coughs, gastrointestinal ailments, and skin irritations.
4. Black cohosh treat a variety of conditions including colds, pain, rheumatism,
5. Alovera Treatment of burns and wounds
6. foxglove Heart failure treatment
7. Monetery pine Full of Antioxidants may protect against age-related decline in mental abilities
3/18/2015
Cont: Sr.No Plants name Medicinal use
8. Oplopanax species Infection cure, diabetes and tuberculosis treatment
9. Autumn crocus Cancer and gout treatment
10. Camphor tree Rheumatic pain relief
11. Cinchona species Malaria and heart- disease treatment
12. Hoodia plant Weight loss
13. Opium poppy Pain relief, cough suppression
14. Xi shu tree Ovarian and lung cancer treatment3/18/2015
Some endangered medicinal plants.
3/18/2015
Some other endangered plants
• Echinacea paradoxa
• Glandularia tampensis
• Heliconia angusta
• Acacia koaia -
• Acampe longifolia
• Guaiacum officinale
• Guaiacum santum -
• Lycaste ciliata
3/18/2015
3/18/2015
Echinacea paradoxa
Heliconiaangusta
Acacia koaia
Lycaste ciliata
Guaiacum santum
Argyroxiphiumsandwicense
Pakistan Scenario
• A number of plant species in the country have become extinct while many more are on the verge of extinction.
• Unfortunately no critical work has been done on threatened plants of Pakistan
580-650 flowering plant species (i.e. 12%) are expected to be threatened.
3/18/2015
Extinct plant species in Pakistan
3/18/2015
Asparagus gharoensis (Sindh)
Scaveola plumererii (Sindhcoast)
Allium gilgiticum (Gilgit)
Arabidopsis brevicaulis(Hunza valley)
Saxifraga duthei (Baltistan)
Taraxacum chitralicum(Chitral)
Cont:
3/18/2015
Sonneratia caseolaris (Indus delta)
Nepeta schinidii (Chitral)
Bruguiera gymnorrhiza (Indus delta)
Cousinia matifeldei (Chitral)
Scaveola taccada (Sindhcoast)
Pedicularis caeruleoalbescens(Chitral)
3/18/2015
Asparagus gharoensisScaevola plumieri Arabidopsis
brevicaulis
Sonneratia caseolarisBruguiera gymnorrhiza
Allium gilgiticum
Reasons of declining plant diversity
Beginning in the 1960s and 1970s, the Green Revolution introduced high-yielding varieties of rice and wheat to the developing world, replacing thousands of farmers' traditional crop varieties and their wild relatives on a massive scale. The same process continues today. New, uniform plant varieties are replacing farmer's traditional varieties -and the traditional ones are becoming extinct.
3/18/2015
• Pests have became more resistant against the pesticides and their efficiency to target the crops has been increased. Ultimately traditional crops are more vulnerable to these pests.
3/18/2015
• On the other hand excessive use of pesticides has also killed the natural predator of pests causing more damage to crops than past.
• Due to the lake of gene banks efficiency in the best operating order to preserve different plants genes.
• Pakistan lacks a botanical survey department, as it exists in many regional countries, including India, and a book on the status of its flora.
3/18/2015
• Wildlife habitat declined with the advent of row-to-row tillage and the adoption of a monoculture system that eliminates crop rotation and leads to loss in plants diversity.
• Wetland clearance for agricultural purposes.
• Almost 80% wetland has been cleared for agricultural purposes.
3/18/2015
Recall
• AI can be defined by three major ways:
increasing yields per hectare
increasing cropping
intensity (i.e. two or more
crops) per unit of land
changing land use from low value crops or
commodities to those that
receive higher market prices
AI: a driver of biodiversity loss during last decades
Reasons include:
Conversion of complex natural ecosystems to simplified managed
ecosystems
intensification of resource use
application of more agrochemicals
a generally higher input and output
Agronomically important, high-intensity pastures in Germany lost around half
of the plant species in post-war Europe and are now extremely species
poor
seed density in arable soils steeply decreased
from 1900 onwards
Recent AI also includes GMCs, which offer new
opportunities for increased yields in the
coming decades, but also risk side-effect
species losses are because of both deterministic (by agricultural expansion)
and stochastic processes (by habitat fragmentation)
decline of biodiversity may affect ecosystem functioning and yield
In Centrral Europe, nature reserves are anthropogenic and
endangered by AI
Insecticide applications in rice fields of south and Southeast Asia causing
removal of predators thus pest resurgence
the impact of AI on biodiversity is not uniform and some groups of species are more affected than
others
In Western Europe, AI effects on plants, beetles and birds. Examples
In another study use of insecticides and fungicides had consistent negative effects on biodiversity in Europe
Impact on farmland birds and aquatic specie
reduces the number of flowers and plant diversity
In the northwestern Gulf of Mexico, nutrient enrichment mainly from fertilizer use in the Mississippi Basin has accounted
for the world’s largest hypoxic or dead zone
Sunstainable intensification
The goal of sustainable
intensification is
increase food production
from existing farmland
Minimisepressure on
the environment
Increasing demand for food from growing global
Populaion
It is a response to
challenges of
In short supply,
Over exploited
Used unsustainably.
In a world where land,
water, energy and other
outputs are
Sustainable intensification
•Main purpose is to meet rising food demand due to population increase using fewer resources and through efficient
use of new technologies Drip irrigation,
sprinklers, no-till beneficial
making productive
use of human capital in the
form of knowledge
social capital to resolve common landscape problemsThis system is less vulnerable to shocks and stresses
Socio-economic intens..
Building social capital, human
capital, sustainable livelihoods
Ecological intens..
Intercropping, IPM, O.F
Genetic intens..
Higher yields, improving nutrition,
resilience to pests, diseases
& CC
Examples China: focus is on achieving both high crop productivity and high resource use efficiency ensuring food security and env. Sustainability•this system has been successfully tested and demonstrated•policies for sustainable intensification in cultivated land are also proposed by govt.
AI in Africa: benefits for 10.39 million farmers and their families and improvements on approximately 12.75 million ha•Multiplicative food outputs, high yield/ha•Still more gaps to be filled (finance, collaboration among partners, political leadership)
Europe is the most intense agriculture producing
country and also
employing AI
Need of integrated polices and correlation among all
sectors Detailed
assessment and understanding of AI impacts is imp
Globally 4000 plants and
animals threatened due to
AI
Rare and arable species are
highly sensitive to AI
Low intensity mngt. Tech imp
Link between agriculture and climate change
No doubt,
Agriculture is seriously effected by climate change
But;
It also contributes to the problem at the first place
• Researchers argue that, with the right practices and incentives, smallholder farmers can boost productivity and help beat climate change.
• Any efforts to ‘intensify’ food production must be matched by a concerted focus on making it ‘sustainable.’ Failing to do so will undermine our capacity to continue producing food in the future
Any