Impact of the establishment of a botanical garden on soil carbon sequestration and nutrient availability in tropical soils

The objective of the study was to identify the potential for soil C sequestration associated with the establishment of a botanical garden in the tropics. Since forest resources are dwindling and home gardens are limited botanical gardens could play a major role in mitigating CO2 in the urban environment. This study determined C sequestration and nutrient availability of different thematic areas of a botanical garden 10 years after establishment in comparison with the primary land use, a dry zone forest at the establishment. The establishment of the botanical garden has created a significant improvement of the soil properties with compared to the primary land use. The soil C stocks were significantly high in the botanical garden with compared to the primary land use (7.3 t ha(-1)). Thematic areas such as Arboretum Part B (13.04 t ha(-1)), Herbal Garden (12.5 t ha(-1)) and Valley path (13.23 t ha(-1)) contained the highest amount of C in soil. Management practices used in maintaining this botanical garden may have affected the soil organic carbon and nutrient status of soil. This study showed that botanical gardens established in urban areas have a great capacity to store C and thereby to mitigate global warming.