Kuttanad Wetlands Face Soil Toxicity Risk

Why in News ?

Recent soil tests in the Kuttanad paddy fields of Kerala—part of the Kuttanad Wetland Agricultural System—have revealed elevated aluminium concentrations, raising concerns over soil health, crop productivity, and the long-term sustainability of this globally recognised farming system.

Background & Context

Kuttanad represents one of India’s most ecologically sensitive and unique agricultural landscapes, where farming is carried out below sea level. The region is highly vulnerable to changes in soil chemistry, water management, and climate variability.

Increasing soil acidity—often linked to intensive cultivation, fertiliser use, altered hydrology, and saline intrusion—can mobilise aluminium in soils, posing a serious threat to paddy cultivation. The recent findings have therefore drawn attention to the fragility of wetland agro-ecosystems and the need for sustainable soil management practices.

Kuttanad Wetland Agricultural System: Key Features

Unique Agricultural Landscape

• Only agricultural system in India where rice is cultivated below mean sea level
• Located in Kerala, spanning parts of Alappuzha, Kottayam, and Pathanamthitta districts
• Protected by an extensive network of bunds and water channels

Mosaic Structure of the Kuttanad System

The system comprises a complex, interlinked landscape divided into three major components:

1. Wetlands
   • Paddy cultivation
   • Inland fishing activities
2. Garden Lands
   • Coconut plantations
   • Tuber crops and food crops
3. Water Bodies
   • Inland fisheries
   • Shell and aquatic resource harvesting

This integration supports both livelihood security and ecological balance.

Global Recognition: GIAHS Status

• Recognised as the Kuttanad Below Sea-Level Farming System
• Listed under the Globally Important Agricultural Heritage Systems (GIAHS) programme of the Food and Agriculture Organization (FAO)
• Recognition highlights:
  • Traditional knowledge systems
  • Sustainable land and water management
  • Biodiversity conservation

Aluminium Toxicity: Impact on Soil and Plants

Soil Chemistry

• Aluminium becomes highly soluble and toxic when:
  • Soil pH falls below 5
• Acidic conditions accelerate aluminium release into soil solution

Impact on Crops

• Damages plant root systems
• Inhibits absorption of essential nutrients:
  • Phosphorus
  • Calcium
  • Potassium
  • Magnesium
• Leads to:
  • Stunted growth
  • Reduced yields
  • Increased crop stress

In a wetland system like Kuttanad, such toxicity can significantly undermine food security and farmer livelihoods.

Broader Environmental Concerns

• Rising soil acidity may be linked to:
  • Excessive fertiliser use
  • Changes in water flow and drainage
  • Salinity intrusion due to sea-level rise
• Highlights the vulnerability of below-sea-level farming to climate change
• Calls for integrated soil, water, and nutrient management strategies

Globally Important Agricultural Heritage Systems (GIAHS): Key Facts

• FAO initiative launched at the World Summit for Sustainable Development (2002)
• Objective:
  • Balance conservation, sustainable adaptation, and socioeconomic development
• Recognises agricultural systems of:
  • Outstanding biodiversity
  • Cultural and ecological value

India’s GIAHS Sites

• Koraput Region (Odisha):
  • Traditional subsistence paddy cultivation on highland slopes
• Kuttanad System (Kerala):
  • Unique below-sea-level wetland farming
• Saffron Park of Kashmir:
  • Traditional agro-pastoral saffron cultivation system

Significance for India

• Protecting Kuttanad is vital for:
  • Wetland conservation
  • Climate-resilient agriculture
  • Preservation of indigenous farming knowledge
• Ensuring soil health is essential to maintain:
  • GIAHS status
  • Long-term agricultural sustainability