Carbon Stock and Sequestration Potential of an Agroforestry System in Sabah, Malaysia

Abstract

Total aboveground carbon (TAC) and total soil carbon stock in the agroforestry system at the Balung River Plantation, Sabah, Malaysia were investigated to scientifically support the sustaining of natural forest for mitigating global warming via reducing carbon in the atmosphere. Agroforestry, monoculture, and natural tropical forests were investigated to calculate the carbon stock and sequestration based on three different combinations of oil palm and agarwood in agroforestry systems from 2014 to 2018. These combinations were oil palm (27 years) and agarwood (seven years), oil palm (20 years) and agarwood (seven years), and oil palm (17 years) and agarwood (five years). Monoculture oil palm (16 years), oil palm (six years), and natural tropical forest were set as the control. Three randomly selected plots for agroforestry and monoculture plantation were 0.25 ha (50 × 50 m), respectively, whereas for the natural tropical forest it was 0.09 ha (30 × 30 m). A nondestructive sampling method followed by the allometric equation determined the standing biomass. Organic and shrub layers collected in a square frame (1 × 1 m) were analyzed using the CHN628 series (LECO Corp., MI, USA) for carbon content. Soil bulk density of randomly selected points within the three different layers, that is, 0 to 5, 5 to 10, and 10 to 30 cm were used to determine the total ecosystem carbon (TEC) stock in each agroforestry system which was 79.13, 85.40, and 78.28 Mg C ha−1, respectively. The TEC in the monoculture oil palm was 76.44 and 60.30 Mg C ha−1, whereas natural tropical forest had the highest TEC of 287.29 Mg C ha−1. The forest stand had the highest TEC capacity as compared with the agroforestry and monoculture systems. The impact of planting systems on the TEC showed a statistically significant difference at a 95% confidence interval for the various carbon pools among the agroforestry, monoculture, and natural tropical forests. Therefore, the forest must be sustained because of its higher capacity to store carbon in mitigating global warming.

Carbon Sequestration Potential of Agroforestry Systems in Degraded Landscapes in West Java, Indonesia

“…The carbon stocks of the simple systems (i.e., combination of single trees with cash crop or grass) and mixed-tree system are slightly similar to C stock on agroforestry systems reported by other studies in Indonesia [31,32]. The C stock is found relatively higher in oil palm and agarwood-based systems in Sabah, Malaysia [34]. The mix tree plot systems in our study shows higher potential carbon stock than complex agroforestry system in the buffer zones of a national park in Sulawesi, and mixed tree systems in Bengkulu [33,35].…”

“…In Indonesia's Bengkulu province, mixed tree agroforestry systems store around 95.2 tons ha −1 regardless of age [33]. Carbon stock storage in agroforestry systems with a combination of oil palm and agar wood vary between 78.28 and 79.13 Mg C ha −1 in regard to different levels of soil bulk density [34]. While simple and complex agroforestry systems adjacent to the Lore Lindu National Park buffer zones in Palu, Indonesia show significant differences in carbon stock.…”

Carbon stock estimation of mangrove forest in Sulaman Lake Forest Reserve, Sabah, Malaysia

“…The higher number in this study might be affected by the depth of the soil sample that has been taken which is 1 meter depth compared to the previous study (0.3 meters). However, these reports are in contrast with the study reported by Besar et al (2020) on a natural tropical forest carbon stock value. Their study shows that soil made up only 13% of the total ecosystem carbon stock while the living trees hold the most carbon with 87%.…”

Comperative study of aboveground biomass and carbon storage between Tembawang and conventional rubber agroforestry in West Kalimantan Indonesia

“…When compared to other agroforestry systems, the Tembawang agroforestry system stored more carbon. In a comprehensive report Besar et al, 2020), the carbon storage value of rubber plantation had higher value. In the same DBH range (≥ 10 cm), the carbon storage value in Tembawang agroforestry was in the aboveground carbon storage range of secondary tropical forests in Maluku, Indonesia with an average value of 70.3 Mg C ha -1 (Stas, 2014).…”