Increasing pressure on limited agricultural land in India has resulted in overuse of chemical fertilisers, excessive tillage, jettisoning of age-old organic soil revival practices and lack of appropriate crop rotation. This has resulted in soil degradation and loss of fertility, which are emerging as major challenges for the Indian farmers. Rajesh Aggarwal writes on how to regain the soil health
Increasing penetration of agricultural inputs has helped Indian farmers achieve record food grain production year after year. For the record, the government estimates an all-time high total food grain production of 272 million tonnes in 2016-17. However, this does not automatically imply that all is hunky dory on India’s agricultural front. India’s land area is about 2.5% of the global land area, and it supports more than 16% of the total global human population along with around 20% of the global livestock population.
Clearly, the pressures of constantly increasing production have in turn resulted in a persistent decline in soil fertility– a major challenge that Indian agriculture is currently facing.
With rising population, limited availability of agricultural land, small land holdings and declining soil fertility, India is under serious threat of losing its food surplus status in the near future. According to estimates, the demand for foodgrains is expected to increase from 192 million tonnes in 2000 to 355 million tonnes in 2030.
But, is our ‘fatigued’ soil healthy enough to meet these targets?
Excessive tillage takes a toll
Over the years, increasing pressure on limited agricultural land in India has resulted in overuse of chemical fertilisers on soil, excessive tillage, jettisoning of age-old organic soil revival practices and lack of appropriate crop rotation. This has resulted in soil degradation and loss of fertility, which are emerging as major challenges for the Indian farmers.
Soil degradation is estimated to be severely impacting the 147 million hectares of cultivable land in India, causing a successive deterioration in its productive capacity. In the recent years, experts have witnessed a worrying sign of declining total factor productivity and compound growth rates of major crops. In several agricultural regions across the country, there has been observed a gap between nutrient demand and supply including decline in organic matter status, deficiencies of micronutrients in the soil, soil acidity, salinisation, and sodification.
If we do not take this disturbing trend into account and start acting now, India might be saddled with vast swathes of land rendered infertile by lack of sagaciousness and long-term thinking. Experts say one of the main ways forward is to make agriculture more sustainable and reviving the age-old practices of soil regeneration while balancing the same with judicious use of agrochemicals. The agrochemical industry must also rise to the occasion and invest in producing organic biological products that help improve the health of Indian soil.
What causes soil fertility loss?
Apart from natural factors such as floods, volcanoes, and earthquakes, a number of human-induced factors such as deforestation, ill management of industrial wastes, over-grazing by cattle, and urban expansion, are also responsible for loss of soil’s productive capacity. Widespread land degradation caused by inappropriate agricultural practices has a direct and adverse impact on the food and livelihood security of farmers. Inappropriate agricultural practices that contribute to this include excessive tillage, frequent cropping, poor irrigation and water management and unscientific rotation of crops. Decline in soil organic matter causes limited soil life and poor soil structure.
According to a document prepared by the Indian Institute of Soil Science on the subject, contrary to increasing food demands, the factor productivity and rate of response of crops to applied fertilisers under intensive cropping systems are declining year after year. The current status of nutrient use efficiency remains quite low for most nutrients. For example, in case of Phosphorus, soil’s nutrient use efficiency has been found to be a meager 15-20%; for sulphur 8-12% and for nitrogen 30-50%. Deterioration in the chemical, physical and biological health of the soils are to blame for this condition.
Conventional practices followed by farmers such as leaving the land fallow for some time to allow it regain its lost nutrition, and appropriate crop rotation have been junked in favour of continuous cropping which has led to declining in Soil Organic Carbon (SOC) content to 0.3 – 0.4 percent in the country when it should ideally be at 1 to 1.5 percent. Organic matter plays a key role in maintaining soil fertility by holding nitrogen and sulphur in organic forms and other essential nutrients such as potassium and calcium. The loss of organic matter is accelerated by frequent tillage.
Soil organic carbon plays a key role in maintaining soil fertility by holding nitrogen, phosphorous and a range of other nutrients for plant growth, holding soil particles together as stable aggregates improving soil properties such as water holding capacity and providing gaseous exchange and root growth, plays an important role as food source for soil fauna and flora and even suppresses crop diseases and it acts as a buffer against toxic and harmful substances e.g. sorption of toxins and heavy metals.
As a result of human activities releasing carbon dioxide into the atmosphere, the carbon pool in the atmosphere has increased and the elevated carbon dioxide is considered to be a contributory factor to the danger of global warming and climate change. Soil organic carbon is the largest component of the terrestrial carbon pools, approximately twice the amount of carbon in the atmosphere and in vegetation. If more carbon is stored in the soil as organic carbon, it will reduce the amount present in the atmosphere, and therefore help to alleviate the problem of global warming and climate change.
Need for greater investment in organic products
All this brings us to the vital question of how we can ensure that India’s growing foodgrain needs are met while at the same time the soil health and fertility is nurtured and improved. And the answer lies in turning the focus on biological products to improve soil health, propagating the judicious use of agrochemicals, reducing excessive dependence on fertilisers and pesticides while also reviving practices such as intelligent crop rotation.
With a long-term vision of improving agricultural sustainability, Insecticides India Limited has embarked on a path of innovation to produce products that can transform the health of India’s battered soil. Its latest innovation, Kaya Kalp is a bioproduct that has been created to improve soil’s organic capacity and productivity by replenishing its nutrients, increasing its organic carbon, and improving its physical and chemical properties.
Enhancing sustainable food production through improved soil health is not just the job of the government and cultivators. The agrochemical industry also has a responsibility to invest with a renewed vigour in biological products that can rejuvenate soil health organically. At the same time, the need of the hour is to educate farmers about what they can do to improve the health of their nutrient depleted soil by following practices such as crop rotation and using organic manure boosters such as cow dung and dried leaves. It is also pertinent to educate them about judicious use of agrochemicals and attain a fine balance between chemical and organic products – both of which are critical to India’s food sustainability goals.
(The author is the Managing Director of Insecticides India Ltd. Insecticide India makes all type of insecticides, weedicides, fungicides and PGR for all types of crops and households. The views are author’s own.)