Comparative analysis of carbon and nutrient pools in soils of selected woody ecosystems of central Kerala

Abstract

Present study entitled “Comparative analysis of carbon and nutrient stocks in soils of selected woody ecosystems of central Kerala, India” was carried out at the Academy of Climate Change Education and Research, Kerala Agricultural University, Vellanikkara, Thrissur during 2015-2016. The study showed that the carbon and nutrient stocks were significantly influenced by the treatments. Soil organic carbon is significantly different in each plantation and was significantly higher than corresponding contiguous treeless soils (p < 0.005). Also there was significant reduction in depth. Carbon stock was higher for mahogany plantation (116.01 Mg C ha-1) followed by homestead (105.41 Mg C ha-1) and teak (103Mg C ha-1). Lower carbon stock was found for mango (76.08Mg C ha-1) and acacia (75.19 Mg C ha-1). Carbon stock for each plantation was significantly higher than contiguous open plot. Similarly highest nitrogen and potassium stock was recorded for mahogany plantation (53.61 Mg N ha-1 and 1030.6 Kg K ha-1) which were significantly different from contiguous open plot. Nitrogen stocks were lower for acacia (26.77 Mg N ha-1) and mango (26.77 Mg N ha-1) but are significantly higher from treeless condition. Nitrogen stock in homestead (30.17 Mg N ha-1) and teak (38.29 Mg N ha-1) was higher than acacia and mango but lower than mahogany. Available phosphorous was lower in all woody ecosystems other than homestead (154.56 Kg P ha-1) with significant reduction across depth. The results of the present study revealed that soil organic and nutrient stock varied significantly with woody ecosystems and slow growing species as well as multi-strata ecosystem enrich soil with carbon and nutrient better than fast growing species like acacia. Also is significantly higher than treeless condition. Enhancing tree cover is thus an efficient method to mitigate global warming. Hence choice of the species and their management conditions are important considerations while designing plantation forestry programs particularly when their carbon sequestration and greenhouse gas mitigation potential are considered.