Revitalization of Rivers in India Draft Policy - Isha Guru Jaggi Vasudev

Revitalization of Rivers In India
Draft Policy Recommendation
ANNEXURE 7
SOIL REJUVENATION
Dr. Saravanan Kandasamy 1
ABSTRACT
DECLINE IN SOIL PRODUCTIVITY
Despite significant growth in agriculture over the last four decades in India, most
of our important soil-based production systems are showing signs of fatigue. The
partial factor productivity of fertilizers during the last three and a half decades
showed a declining trend from 15 kg food grains/kg NPK fertilizer in 1970 to 5 kg
food grains/kg NPK fertilizer in 2005, as reported in the Vision 2030 document of
Indian Institute of Soil Science (IISS, 2011).
DETERIORATION OF SOIL FERTILITY
The percentage of samples high in available soil phosphorus has risen five times
from 4% to 20% during the period from 1969 to 2002, and the trend continues to
rise due to non-judicious use of phosphatic fertilizers by farmers. Continuous use
of such fertilizers possessing excessive nutrient loads, with an intention to boost
crop yields, have not only increased the cost of cultivation but also led to nutrient
imbalances in soil and eutrophication of surface water bodies. Analysis of more
than 0.25 million soil samples revealed widespread deficiency of micronutrients:
Zn (49%), S (41%), Fe(12%), Cu (3%), Mn (4%), and B (32% in some selected areas
such as Bihar). The number of elements deficient in Indian soils increased from
one in 1950 to nine in the year 2005-06, which might further increase by the year
2030 if the imbalanced fertilization continues. On the other hand, river canals,
ponds, and lakes receive excessive nutrient inputs from fertilized farm lands
through drainage suffer due to proliferation of aquatic weeds like water hyacinth
and contamination by agrochemical residues.
The existing lacuna in soil chemical test based fertilizer recommendations coupled
with poor soil management practices by farmers (intensive tillage, irrational use
1
Soil scientist, former Assistant Professor, Tamil Nadu Agricultural University
Indian Rivers
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