Page 42 - SCERT Kerala State Syllabus 8th Standard Basic Science Textbooks English Medium Part 1_Neat
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The decline in the fertility of soil and the increase of
pests compel peasants to use fertilizers and pesticides
in greater quantities. The changing
perspective
But though the excessive use of fertilizers and chemical
pesticides provide profit for a short period, gradually High yield seed varieties were
the land may become barren. widely popularised as part of the
It is in these circumstances that the concept of efforts to increase agricultural
sustainable agriculture becomes relevant. Here the production, to meet the demands
of the increasing population.
method adopted is to reduce the use of fertilizers and
This was accompanied by wide
pesticides and to make one's decaying matter a manure
use of fertilizers and pesticides.
for another. Diverse crops are seen in the fields
In this practice, since the seeds
adopting this method. No waste remains. By giving
and fertilizers are brought from
importance to the cultivation of food crops, market
outside to the agricultural field,
dependency and price hike can be reduced. this method may be called HEIA
Conservation of biodiversity also becomes possible by (High External Input Agriculture).
cultivating native varieties of crops. However, this method was
Waste management and sustainable agriculture criticized for its heavy expense
and its adverse effect on health
One of the main problems faced by modern society is and environment. Gradually,
the disposal of organic waste. Will sustainable LEISA (Low External Input
agriculture be an answer for this? Discuss with the Sustainable Agriculture) began to
help of the given indicators and write you conclusions receive wide recognition. LEISA
in the science diary. emphasises the perspective that
• composting only agriculture with minimum
use of external materials can be
• biogas production
sustainable. This method allows
• fodder production the use of fertilizers and
• poultry fodder pesticides in limited quantity,
production under emergency situations. As
a stage ahead, this method
• production of fish feed
envisages NEISA (No External
Input Sustainable Agriculture) as
a possibility, wherein one's
waste becomes the manure for
another and therefore sustainable
and not dependent on anything
from outside.
Fig 3.2 Biogas plant
Basic Science VIII 41
