LAUSR

Albizia saman (Jacquin) F. Mueller belongs to the family Fabaceae (sub family: Mimosoideae) is a native to Northern South America. Commonly known as rain tree and locally known as Thoongu-moonchi maram (Tamil). The species’ introduced during Colonial period as an ornamental tree in Chennai metropolitan city (CMC). Though A. saman represent as a dominant tree species’ in CMC, there are voids in baseline data such as density, biomass stockpile, and annual C sequestration potential hence this study was conducted to fill these voids. A total of 2522 individuals which cover 1672.14 m2 basal area (mean = 9.61 ± 4.95 m2 ha-1; range = 0-24.96 m2 ha-1) was recorded from study plots. During study period A. saman stocked a sum of 6403.51 Mg aboveground biomass (AGB) (mean = 36.8 ± 18.9 Mg ha-1; range = 0-95.4 Mg ha-1) and 3201.76 Mg C (mean = 18.9 ± 9.45 Mg ha-1; range = 0-47.7 Mg ha-1). C storage of individual tree ranged from 3.74 to 4598.18 kg with a mean value of 1269.53 ± 1082.25 kg. On an average, each tree achieved 1.04 ± 0.27 cm horizontal growth yr-1. In a year A. saman population sequestered 111.23 Mg biomass in aboveground (in 174 ha). The mean C sequestration of study area was 319.62 ± 184.0 kg ha-1 year-1. In total, the study area sequestered 55.62 Mg C year-1. Overall, in a year A. saman absorbed 204.13 Mg CO2 for C sequestration in study area. CO2 absorption ranged from 385.46 to 3009.29 kg ha-1 yr-1. The monetary value of C storage and annual sequestration of A. saman is also investigated. Though introduced from tropical Northern South America A. saman provides a considerable ecosystem services to CMC through C storage and sequestration. This study estimated monetary values of just two ecosystem services of A. saman, study that concentrates on all ecosystem services is essential to assess total actual ecosystem service values.