Soil Nutrient Status of Moist·Deciduous Forests at Sigiriya Sanctuary, Sri Lanka Across a Chronosequence of Forest Age

Soil nutrient levels in moist-deciduous forests at Sigiriya Sanctuary, Sri Lanka, show significant recovery and stabilization within 20-25 years after swidden farming. The study found that while total nitrogen content increases with forest succession, mineralizable nitrogen remains immobilized in soil litter due to high termite activity. Total carbon content rises sharply in 10-15-year-old forests following self-thinning of plant individuals, though labile carbon takes longer to build up. Phosphorus and calcium levels were lower in young successional forests but matched mature forest levels by 20-25 years, suggesting potential for rehabilitation into climax forests. Potassium content peaked in 10-15-year-old forests, likely due to litter incorporation from self-thinning. The research highlights that swidden farming reduces soil nutrients, but a rotation period of at least 15 years allows nutrient recovery, preventing forest degradation.

Ekanayaka, E. M. S., Perera, G. A. D., & Seneviratne, G. (2013). SOIL NUTRIENT STATUS OF MOIST·DECIDUOUS FORESTS AT SIGIRIYA SANCTUARY, SRI LANKA ACROSS A CHRONOSEQUENCE OF FOREST AGE. Proceedings of International Forestry and Environment Symposium, 0(0). https://doi.org/10.31357/fesympo.v0i0.1500