MTSA : Pathway showing interlikages between different components of farming
system
Different pathways through which inter-linkages between different sub-systems of a
farming system can be studied. Some of the possible inter-linkages between soil
ecosystem, crop eco-system, and water eco-system.
The following two charts show the interlinkages between soil ecosystem and plants.
nutrients
water
Soil ecosystem
plants
micro-organisms
biomass
nutrients
root exudates
suitable environment
(evolution into higher forms)
soil ecosystem
plants
Soil development
symbiosis
mycorrhiza
survival
micro-organisms
rock weathering & soil formation
land development
prevents soil erosion
land reclamation
improves soil characteristics
- structure
- composition
- pH
- aeration
- water holding capacity
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Livestock soil ecosystem linkages
fodder
crop
livestock
organic matter
soil ecosystem
(waste & dead matter)
nutrients
(salts licks, charcoal )
Overgrazing
soil erosion
The basic linkage at which the class arrived at unanimity is shown below
fodder
deficient or
excess nutrient
pest management
(duck grazing)
feed
disorder
livestock
soil eco-system
micro-organisms
& pathogens
organic matter
trampling
overgrazing
compaction
erosion
health
changes in the
successive profile
of the species
quality of
pasture
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crop
water
What role does livestock play in maintaining the ecological balance ?
Livestock produces organic matter which affects soil properties directly and it also affects
the soil properties indirectly as it helps in the activities of different types of
microorganisms and pathogens. Trampling by livestock results in soil compaction.
Overgrazing by the livestock leaves the soil bare making it more prone to erosion.
Overgrazing also results in changes in the succession profile of species which is
sometimes responsible for the degraded quality of pasture which in turn affects the health
of the livestock. Though overgrazing is bad, but grazing plays a positive role in
maintaining the ecological balance in some cases. There are two very interesting cases of
change in the profile of the species in an area as a result of the inter linkages between the
livestock and the crop ecosystem
1) In valley of flowers in India grazing was banned, as a result of which grasses grew
indiscriminately and it dominated the valley and there were no flowers next year.
2) In Bharatpur bird sanctuary grazing was banned, as a result of which birds could not
prey on worms present the ground and within a short period of time the population of the
birds decreased dramatically.
Livestock transports energy from one place to another in a sense that they graze at one
point and then leave their excreta at another point, thus helping in transporting the energy
from one place to another.
As a matter of tendency cattle do not graze on the grass not less than four inches tall and
the reverse is true for the sheep. This also sometimes might affect the ecology.
Why the fodders of local varieties are preferred ?
Fodder of local varieties is believed to be better for the livestock than the fodder from the
improved varieties because in local varieties the harvest index is generally lower.
Harvest index = Grain yield / fodder yield
Livestock takes salts directly and also in the form of fodder from the soil. So if the soil is
either deficient or excess in some mineral then it might affect the health of the animals.
One example of this is when cattle are made to graze in an area very rich in fluorides
then excess fluorides affects their dentures. In another case if the soil is deficient in some
essential mineral then the animals grazing on it also show deficiency symptoms.
There are some species of plants whose seeds would not germinate unless they are made
to pass through the digestive system of the livestock.
Bones and horns of the livestock are used in agriculture for manorial and disease
control purposes.
In quite a few places in India penning, is practiced. It is putting all the livestock on a
harvested plot overnight so that they leave their excreta on that plot and enrich the soil in
the process.
Sometimes livestock is used for pest-management also. In some places in south India
duck grazing is practiced especially in paddy fields and they clear the field from insects
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by preying on them. Also some small innovative practices are used, e.g. banana plants are
grown around the crop fields, rustling of banana leaves scares rats and some other pests
who otherwise would cause significant damage to the crop. In some places like in Andhra
Pradesh in India and in Bhutan snake houses are made in the fields as snakes pry on pests
like rats and so are believed to be very beneficial for the ecology.
Live stock in hilly areas are very important not only for the direct benefits derived from
them but also because of the organic matter produced by them is very important in hilly
areas.
Tree
canopy
shelter birds
shade
wind breaker
influence water table
transport mineral & water
sink function
(CO2 sequestering)
Crops are used for thatching, plastering and fencing which after 2-3 years are mixed in
the soil which increases the fertility of the soil. In alkaline soils Amblica officinalis grows
well.
What is entropy and what is its significance from the environmental point of view ?
Entropy is defined as the movement of a energy or matter from orderliness to
disorderliness. It was proved scientifically that entropy is reduced if the energy is carried
through an organic channel as the dissipation of energy through an organic channel is
always less than through an inorganic channel. Entropy of our environment has been on
an increase for quite long. So it is always suggested to use an organic channel rather than
using an inorganic channel.
Environmental regulations in the post GATT phases.
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US put a legal ban on marketing of the lobsters of less than a certain size on the pretext
that they are not mature at that stage and should not be caught at that stage. So the export
of Canadian lobsters to US was affected to a great extent. This was more so because of
the reason that in Canada the lobsters mature at an younger age and at the time of
maturity their size is lesser than the prescribed size of US. So there were two options in
front of Canada, to solve the matter bilaterally under the auspices of NAFTA or to go to
WTO for pleading. Canada preferred to go to WTO. A committee was formed to look
into the matter which after much deliberations came to the conclusion that in the market,
it is the size of the lobsters which only can distinguish matured lobsters from the
unmatured ones. So the US restriction was upheld.
In another incidence US made an allegation against Mexico and EEC that while catching
Tuna fish in the Pacific ocean a large number of Dolphins were also being caught by
them. Dolphins were an endangered species and efforts were being made worldwide to
conserve the species. The matter was taken up by the WTO, and US lost the case. The
arguments given by WTO was that the ban will give US a discriminatory advantage
against others and the second reason given was that the matter was an extra judicial
subject for US as the Pacific Ocean did not come under the jurisdiction of US. Also the
Dolphions were endangered in not just pacific waters. US vessels violated this ban in
other regions.
Consumer preference for safe food
Do we
really have a
choice ???
Preference for safe food.
It is observed that these days more and more number of people are becoming aware of
the importance of safe food and given a chance they would prefer to take food free from
any kind of chemical residuals. But the question arises, do we really have a choice to take
safe food in a time when in almost all parts of the world chemicals are in heavy use for
agricultural purposes. The following options may exist:
Options
diverse genetic population
change in production technology
abetment of residues
Increase supply
Decrease demand
Own production
Shift to sustainable agriculture
Import
Change the technology
CSA
Organic certification
Efficient extraction
biotechnology
apomixis in hybridization
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Awareness
Policy
Bioethics
There was an apprehension raised that even if in future the safe foods were available in
plenty, their prices were going to remain very high. In a poor and developing country like
India where a huge proportion of population is still struggling under poverty line , and
where the purchasing power of average people is very low, whether a common person
could afford to buy these safe foods.
It is the poorest of poor, who can not afford to buy so called good food from market is the
one who is taking safe food in the real sense because his staple food include millets in
which the use of chemicals is relatively very low and also he cannot afford to use the
chemicals in his field. If the technological change could be brought about in the areas of
production technology, efficient extraction technology, and abetment of residual toxicity
of foods then the purpose could be solved to a great extent. Also by the help of
biotechnology and hybridization, new resistant varieties could be developed, which will
reduce the dependence of agriculture on chemical to get a good yield. Other factors
which may play a major role towards this are: consumer awareness, by changing the
government policies and by introducing the concept of Bioethics. Nevertheless efficacy
and implementability of all these programmes still is under a big question mark.
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