WORLD
SOIL DAY - ENVIRONMENT
NEWS: World Soil Day, celebrated annually on December 5,
raises global awareness about the critical role of soil in sustaining
life.
WHAT’S IN THE NEWS?
World Soil Day
- Background: The concept of World Soil Day was introduced by
the International Union of Soil Sciences (IUSS) in 2002.
- The FAO Conference unanimously endorsed World
Soil Day in June 2013 and in December 2013, the UN
General Assembly responded by designating 5 December 2014 as the
first official World Soil Day.
- Theme for 2024: Caring for Soils: Measure, Monitor,
Manage.
The Crisis of Soil in
India
- Prevalence of Nutrient Deficiencies
in Topsoil
- Senior scientists at the Global Soils
Conference highlighted a critical reality: nearly 90% of India’s
topsoil suffers from severe nitrogen and phosphorus deficiencies,
key nutrients essential for crop growth and soil fertility.
- Furthermore, 50% of the soil in the
country lacks adequate levels of potassium, another crucial
nutrient for healthy crop yields.
- Contributing Factors to Soil
Degradation
- The crisis is exacerbated by multiple factors,
including erosion, which strips away fertile topsoil, and depletion
of soil nutrients, resulting from unsustainable agricultural
practices.
- A consistent decline in soil organic carbon
levels, which plays a pivotal role in maintaining soil structure and
fertility, further aggravates the issue.
- Long-term Implications of Soil
Degradation
- The depletion and degradation of soil
resources have far-reaching consequences for India’s agricultural
productivity and sustainability.
- These challenges also undermine the country’s
ability to maintain ecosystem health, ensure food security,
and strengthen climate resilience, making the soil crisis a
national priority.
The Case for Nutrient
Circularity as a Solution
- Understanding Nutrient Circularity
- Nutrient circularity refers to the recovery,
processing, and redistribution of nutrients from urban organic waste
back into agricultural soils.
- This process addresses the dual challenges of
declining soil fertility and the growing burden of managing enormous
quantities of urban waste.
- Potential Benefits of Nutrient
Circularity
- By replenishing nutrient-deficient soils,
nutrient circularity offers a pathway to improve soil health while
also reducing the volume of waste that requires disposal or treatment.
- For India, which generates substantial
quantities of unmanageable waste, nutrient circularity provides a
scalable solution to achieve sustainability and circularity at
both urban and rural levels.
Importance of Soil
- Foundation of Life: Soil supports plant growth by providing
essential nutrients, water, and oxygen, forming the base of terrestrial
food chains.
- Ecosystem Services: Acts as a natural water filter, removing pollutants
and replenishing groundwater.
- Climate Regulation: Plays a significant role in carbon
sequestration, mitigating climate change by storing atmospheric carbon
dioxide.
- Biodiversity Hotspot: Soil houses diverse organisms, from microbes to
insects, which facilitate nutrient cycling and enhance plant health.
India's Current Waste
Management Scenario
The Role of
Waste-to-Energy (WtE) Plants
- Types of Waste-to-Energy Technologies
- India relies on two primary WtE technologies:
- Mass incineration, which involves burning waste at high
temperatures to produce energy.
- Bio-methanation, which uses organic waste to produce biogas
through anaerobic digestion.
- Among these, incineration dominates,
accounting for 81% of the waste treated through WtE technologies.
- Challenges of Incineration-Based WtE
Plants
- Incineration-based plants demand high
capital investment (CapEx) and incur substantial operational costs
(OpEx), making them financially burdensome.
- These plants generate hazardous ash and
toxic byproducts, posing significant environmental and public health
risks.
- Despite their intended purpose, they are prone
to failure, with half of India’s 14 incineration plants (total
capacity 130 MW) becoming non-operational due to economic unviability and
poor waste composition (high moisture content and low calorific value).
- They emit 1707 g of CO2 equivalent per
kilowatt-hour, a level far exceeding emissions from other energy
sources, raising serious greenhouse gas and air pollution concerns.
- Challenges of Bio-Methanation-Based
WtE Plants
- Bio-methanation plants, while avoiding the
risks associated with incineration, face challenges such as:
- The
requirement for high-quality segregated organic waste.
- Dependence
on skilled personnel for maintenance and operations.
- Risks of methane
leakages, which have a global warming potential much higher than
carbon dioxide.
- Failure rates remain high in cities like
Bengaluru, Salem, and Lucknow due to poor segregation practices.
- WtE Contribution to Renewable Energy
- Despite the emphasis on WtE technologies, they
contribute a mere 0.1% to India’s total renewable energy
generation, compared to the 26% contribution from solar and wind
technologies.
Nutrient Circularity and
Composting: A Sustainable Alternative
Restoring Nutrient
Circularity Through Composting
- Reconnecting Urban Organic Waste with
Agriculture
- Nutrient circularity addresses the flow of
nutrients from rural areas (via crops) to urban centers by recovering
organic waste and transforming it into compost that can be returned to
agricultural fields.
- Advantages of Compost over Chemical
Fertilisers
- Compost derived from municipal solid waste is
rich in organic carbon, a critical component for improving soil
structure and water retention.
- When combined with chemical fertilisers,
compost improves soil health at two-thirds the cost per hectare
compared to chemical fertilisers alone, reducing production costs by 15–20%.
- Composting reduces dependence on chemical
fertilisers, offering a more sustainable approach to soil enrichment.
Policy Support and
Failures
- Policy on Promotion of City Compost
(2016)
- Introduced a subsidy of ₹1,500 per tonne
of compost to encourage adoption.
- The policy failed due to:
- Lack of
emphasis on ensuring compost quality.
- Inadequate
testing standards, laboratories, and certification systems.
- Absence
of public awareness campaigns to create demand.
- Withdrawal of Support in 2021
- The government ceased all funding and
incentives for composting, redirecting financial support exclusively to
bio-methanation.
Scaling Composting as a
Viable Solution
- Comparative Advantages of Composting
- Composting can be implemented at multiple
scales, from small neighborhoods to municipal levels, with lower costs
and complexity than bio-methanation.
- Existing Successful Models
- Chikkaballapur,
Karnataka:
Converted 759 tonnes of legacy waste into compost, benefiting 109
farmers across 17 villages.
- Alappuzha
Municipality, Kerala:
Implemented a hub-and-spoke model, transferring urban compost to
rural agricultural areas.
- Policy and Public Engagement
- To scale nutrient circularity, India needs a two-pronged
approach:
- Top-down interventions, such as government policies to improve
compost quality, incentivize production, and foster public-private
partnerships.
- Bottom-up initiatives, including public awareness campaigns to
build demand for compost among farmers and communities.
Conclusion: Reviving
Traditional Practices for Modern Challenges
- Nutrient
circularity, a time-tested practice in Indian households, offers a
scalable and adaptable solution to the soil and waste crises.
- By
implementing well-supported composting models, the country can regenerate
degraded soils, reduce reliance on chemical inputs, and create healthier
urban and rural ecosystems.
- A combined
effort from policymakers, stakeholders, and citizens is essential to
transform this vision into reality.
Source:
https://www.downtoearth.org.in/environment/world-soil-day-it-is-time-to-shift-focus-on-its-health-as-it-sustains-ecosystems-food-security-and-climate-resilience