Carbon pool and sequestration potential of village bamboos in the agroforestry system of northeast India

Bamboo forms an important component in the rural landscape of northeast India. Carbon (C) pool and sequestration potential of bamboos in the land managed by farmers was studied in Cachar district, Assam, northeast India. Allometric equations were developed by harvest method relating leaf, branch and culm biomass with DBH as an independent variable to determine the stand biomass and productivity. C pool and C sequestration in different bamboo culm components was determined by multiplying the biomass with C concentration. C pool in the above ground biomass ranged from 21.69 Mg ha-1 during 2003 to 76.55 Mg ha-1 during 2006. Allocation of C was more in culm components (85 - 89 %) than in branch (8 - 10 %) and leaf (3 - 4 %). Both current and one year old culm constituted 58 - 73 % (15.86 - 35.63 Mg ha -1 ) of the total above ground C pool. The rate of above ground C sequestration was 18.93 - 23.55 Mg ha -1 yr -1 with the mean of 21.36 Mg ha-1 yr-1. Of the total annual C sequestration, 82 - 89 % was contributed by new culms and through culm age increment and 14 - 18 % by annual total litter production. Management of village bamboos as a potential source of C sink by smallholder farmers is discussed. Resumen: El bambu constituye un componenteimportante en el paisaje rural del nordestede la India. Se estudio el almacen y el secuestro potencial de carbono (C) de los bambues en terrenos agricolas manejados en el distrito Cachar, Assam, nordeste de la India. Por medio del metodo de la cosecha se desarrollaron ecuaciones alometricas que relacionan la biomasa de la hoja, la rama y el culmo con el DAPcomo variable independiente,a fin de determinarla biomasa y la productividad del rodal. El almacen de C y el secuestro de C en diferentescomponentes del culmo del bambufueron determinados multiplicandolabiomasapor la concentracion de C. El almacen de C en labiomasa aerea fluctuo entre 21.69 Mg ha-1en 2003 y 76.55 Mg ha -1 en2006. La asignacion de C fue mayor en los componentesdel culmo (85 - 89 %) que en el tallo (8 - 10 %) y las hojas (3 - 4 %). Tanto el culmo actual como el de un ano de edad constituyeron 58 - 73 % (15.86-35.63 Mg ha-1) del almacen aereo total de C. La tasa de secuestro aereo de carbono fue de 18.93-23.55 Mg ha-1 ano-1, con una media de 21.36 Mg ha-1 ano-1. Del secuestro total anual de C, los nuevos culmos contribuyeron con entre 82 y 89 % a traves del incremento en edad de los culmos, y 14 - 18 % por la produccion total anual de mantillo. Se discute el manejo de los bambues de las aldeas por parte de los pequenos agricultores como unafuente potencial de sumideros de C. Resumo: Os bambussao uma componente importante da paisagem rural do nordeste da India. O reservatorio de carbono (C) e o sequestro potencial dos bambus no solo gerido pelos agricultores foi estudado no distrito de Cachar, Assam, nordeste da India. Desenvolveram-se equacoes alometricas por um metodo de abate relacionando a biomassa das folhas, ramos e colmo com o DAP, como variavel independente, para determinar a biomassa da parcela e a produtividade. O reservatorio de C e o seu sequestro nas diferentes componentes do colmo dos