Allometric Equations for the Biomass Estimation of Calophyllum inophyllum L. in Java, Indonesia

Abstract

Reliable data on CO2 quantification is increasingly important to quantify the climate benefits of forest landscape restoration and international commitments, such as the Warsaw REDD+ Framework and Nationally Determined Contributions under the Paris Agreement. Calophyllum inophyllum L. (nyamplung as a local name or tamanu tree for the commercial name) is an increasingly popular tree species in forest landscape restoration and bioenergy production for a variety of reasons. In this paper, we present allometric equations for aboveground biomass (AGB), belowground biomass (BGB), and total above- and belowground biomass (TABGB) predictions of C. inophyllum L. Data collection was carried out twice (2017 and 2021) from 40 trees in Java, Indonesia. Allometric equations using the natural logarithm of diameter at breast height (lnDBH) and ln height (lnH) for biomass prediction qualified the model’s fit with statistical significance at 95% of the confidence interval for AGB, BGB, and TABGB predictions. The results showed that the linear models using both lnDBH and lnH were well fit and accurate. However, the model with lnDBH is more precise than the model using lnH. Using lnDBH as a predictor, the R2 values were 0.923, 0.945, and 0.932, and MAPE were 24.7, 37.0, and 25.8 for AGB, BGB, and TABGB, respectively. Using lnH as a predictor, the R2 values were 0.887, 0.918, and 0.898 and MAPE were 37.4, 49.0, and 39.8 for AGB, BGB, and TABGB, respectively. Consequently, the driven allometric equations can help accurate biomass quantification for carbon-trading schemes of C. inophyllum L.

Estimation of tree biomass and carbon stock in the Tangkoko Nature Reserve, North Sulawesi

“…Trees in 60 -<70 cm dbh contributed 47% of the AGB fractions. Above this diameter range, the AGB fractions decrease, this could be related to the lesser tree density of the diameter range and also to the hollowstemmed Ficus strangler which reduced the contribution of large diameter classes on ABG [13]. Furthermore, species contribution to total biomass (AGB and BGB) can be seen in Figure 4.…”

Carbon sequestration potential of Tamanu (Calophyllum inophyllum) in Gunung Kidul, Yogyakarta

“…Each tree in the measurement plot was recorded for species and measured for DBH. Aboveground biomass per tree was calculated using the allometric equation developed by Basuki, Leksono, Baral, Andini, Wahyuni, Artati, Choi, Shin, Kim, Yang, Samsudin and Windyarini [11] for Tamanu species, i.e. :…”

“…Tamanu, a plant species found in abundant numbers along coastal parts of tropical areas, has garnered significant interest due to its various noteworthy attributes [4]. These include its valuable timber [5], medicinal capabilities [6,7], biodiesel potential [8,9], and its capacity to trap considerable quantities of carbon [10,11]. The forestry sector has various mitigation alternatives at its disposal, including the extension of carbon retention in harvested wood products, product substitution, and the production of biomass for bio-energy [12].…”

Carbon Stock Assessment of Four Selected Agroforestry Systems in Owerri-West Local Government Area, Nigeria

“…Soil C stock for the 0-60 cm soil layer differs among different land uses and regions". Nair et al [11,12] noted that "C stock in the 0-60 cm soil layer is 121-123 t ha −1 for tropical forests and 110-117 t ha −1 for tropical savanna". "The results obtained from various studies on agroforestry practices in diverse ecological conditions showed that treebased agricultural systems, compared to treeless systems, stored more carbon in deeper soil layers near the tree than away from the tree; higher soil organic carbon content was associated with higher species richness and tree density" [11].…”