Indian Journal of Soil Conservation

Nitrogen fixing trees (NFTs) are integral part of the indigenous agroforestry plantations on farms. The nitrogen fixing species accumulate more C due to their efficient system of fixation of nitrogen and the carbon in their parts. Increased N inputs most likely increase soil C storage by increasing biomass diversity and production. The present stydy was conducted to study the effect of nitrogen fixing trees viz., Acacia nilotica, Acacia auriculiformis, Acacia albida, Leucena leucocephala, Albizia lebbeck, Acacia catechu, Dalbergia sissoo and Bauhinia variegata on the growth biomass site amelioration and carbon sequestration. The results revealed that the maximum tree height and diameter was recorded in A. albida closely followed by D. sissoo and B. variegata. A. nilotica was the poor performer with 20% survival and 6.86 m height tree ^.-1. It was most affected by the diseases among all the species. The mean annual increment was higher in first six years among all the NFT species. The maximum mean annual increment in height was recorded to be 0.57 m yr ⁻¹ whereas the maximum mean annual increment in DBH was recorded in L. leucocephala to the tune of 1.03 cm yr ⁻¹. Carbon stocks in were D. sissoo 145.2 and 42.12 t ha⁻¹ in above and below ground parts, respectively. It was closely followed by A. albida. Carbon dioxide mitigation potential of D. sissoo was maximum to the tune of 28.42 t ha⁻¹ yr⁻¹. The studies concluded that D. sissoo is the highest carbon sequestering species with maximum survival and growth in subtropical climate.