Carbon stock and sequestration potential of poplar and catalpa based silvipasture system in temperate environment of Indian Himalaya

Abstract

Global climate change caused by rising levels of carbon dioxide and other greenhouse gases is recognized as a serious environmental issue and the relevance of agroforestry for mitigating the same has got global recognition. The present study on the same basis was conducted on 28 year old silvipasture system in the central region of Kashmir Himalaya, India. The experimental trial was laid in the field in the year 1993 with tree component represented by Populus deltoids & Catalpa bignonioides and ground floor by Phleum pretense. The results revealed that poplars had a mean volume of 1.33 m³ after 25 years and sequestered 43.38 tones of CO₂ per hectare per year and whereas an average volume of 0.095m³ was calculated for catalpa trees. Carbon accumulation rate and CO₂ sequestered was to the tune of 2.45 and 8.97 t ha^-1 per year respectively in highest diameter classes of 20-25 cm. The carbon stock in the grass component was 13.46 and 13.05 t ha^-1 under poplar and catalpa and accordingly CO₂ sequestered by the perennial grass was 22.14 and 21.48 t ha^-1 yr^-1 respectively. Soil carbon recorded under different tree based silvipasture system contributed between 47.25 to 48.30 t ha^-1 of soil carbon up to 30 cm depth. Poplar based silvipasture system recorded a total maximum carbon of 384.36 t ha^-1 followed by combination of poplar, catalpa & grass based silvipasture system 237.59 t ha^-1. Catalpa based system recorded only 87.74 t ha^-1 of C because of its slow growth. Soil carbon recorded under different tree based silvipasture system contributed between 47.25 to 48.50 t ha^-1 of soil carbon up to 30 cm depth. These types of landuse systems can be potential candidates for carbon sequestration and climate change mitigation apart from providing sustainable fodder resource. These types of silvipastoral models can be recommended to other parts of Himalayan region for general welfare of farming communities and global climate change mitigation in general.