Discuss environmental impacts caused by the excessive use of chemical fertilizers

i) Eutrophication:
The term eutrophication has been derived from Greek word which means well
nourished. It describes a condition of lakes or reservoirs involving excess algal growth,
which eventually cause the destruction. The first step in eutrophication of a body of
water has been an input of nutrients from sewerage or agricultural runoff. The nutrient
rich body of water gives rise to a great deal of plant biomass by photosynthesis, and a
smaller amount of secondary animal biomass. Dead biomass gets accumulated in the
bottom of the lake, where it partially decays, recycling nutrient, carbon dioxide,
phosphorus, nitrogen and potassium. If the lake has been not too deep, bottom rotted
plants begin to grow accelerating the accumulation of solid material in the basin.
Eventually, a marsh is formed which finally fills to produce a dry land or forest.
The eutrophication process has been not a new phenomenon. It has been basically
responsible for the formation of huge deposits of coal and other fossil fuels. However,
mans activities are able to accelerate eutrophication. The excessive use of chemical
fertilizers produces increased growth of algae and other aquatic plants which may clog
off river and lakes.

ii) Change in soil acidity:
Excess use of some fertilizers may pollute the soil. If excess (NH 4 ) 2 SO 4 is used in the
same field, then NH 4 + ions are used by the crops but the SO 4 2- ions get accumulated into
the soil and it causes soil highly acidic. Similarly, accumulation of Na + ,K + ions into the
soil make the soil alkaline.

iii)Soil Texture:
Excess use of fertilizers changes the soil texture.
iv) Higher level of nitrates in the drinking water would result many diseases.
v) Denetrification of nitrates into the oxides of nitrogen particularly N 2 O may harm the
ozone layer.

---

NatalieR answered the question on May 23, 2022 at 07:03