Soil tests in Kuttanad paddy fields (Kerala)– part of Kuttanad Wetland Agricultural System revealed dangerously high aluminium concentrations, posing a serious threat to crop health, soil fertility, and productivity in India’s famous below-sea-level rice-farming region.
Key Findings from Soil Tests
- Tests conducted by the Kerala Centre for Pest Management (KCPM) and analysed at the Rice Research Station, Vyttila (Kerala Agricultural University).
- Aluminium concentration detected: 77.51 ppm to 334.10 ppm
- Permissible limit for rice soils: 2 ppm
- Contamination levels are 39–165 times higher than safe limits.
Why Aluminium Toxicity Occurs
- Aluminium becomes highly soluble and toxic in acidic soils (pH < 5).
- Leads to:
- Root damage & restricted root growth
- Poor uptake of phosphorus, calcium, potassium, magnesium
- Reduced crop yield & poor plant vigour
Kuttanad Wetland Agricultural System (Kerala)
- Known as the “Rice Bowl of Kerala”.
- Only agricultural system in India that supports rice cultivation below sea level.
- Farming landscape created by reclaiming and draining deltaic brackish-water swamps.
Landscape Structure (Three Components)
- Wetlands – paddy cultivation & fish catching
- Garden lands – coconut, tubers, food crops
- Water areas – inland fishing & shell collection
Global Recognition
- Recognised as a Globally Important Agricultural Heritage System (GIAHS) by FAO.
Impact of Aluminium Toxicity on Soil & Crops
- Increased aluminium solubility under acidic conditions- root injury
- Disrupts nutrient absorption- nutrient deficiency despite fertilization
- Weak plant growth- low productivity & higher crop stress
- Long-term risk of soil degradation & ecological imbalance
Strategic Importance of Kuttanad
- Traditional water management systems protect fields from flooding & saline ingress
- Supports rice–fish–coconut integrated farming
- Sustains livelihoods in wetland-dependent communities
Globally Important Agricultural Heritage Systems (GIAHS)- FAO
- Launched at World Summit on Sustainable Development (2002).
- Objective: Balance heritage conservation + sustainable agriculture + community livelihoods.
India’s Sites under GIAHS
- Koraput (Odisha) – Indigenous paddy diversity & subsistence hill farming
- Kuttanad (Kerala) – Below-sea-level wetland rice farming
- Kashmir Saffron Heritage Landscape – Traditional saffron agro-pastoral system