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

ABSTRACT

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.

KEYWORDS:

• Carbon sequestration
• microbial biomass C
• total organic C
• soil carbon stocks
• soil nutrients

Acknowledgements

The authors would like to thank Ms. R.K.C. Karunaratne and Mr. A.K. Pathirana, Senior Technical Officers at NIFS, for assistance in the laboratory analysis and Mr. Asanga Pushpakumara for sampling and sample preparation. The authors are thankful to Dr. D.H.P. Peramunugama, Director General, Department of National Botanic Gardens, for providing permission to carry out this research.

Disclosure statement

No potential conflict of interest was reported by the authors.

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.