Mangrove Above-Ground Biomass and Carbon Stock in the Karimunjawa-Kemujan Islands Estimated from Unmanned Aerial Vehicle-Imagery

Blue carbon ecosystems in the Karimunjawa Islands may play a vital role in absorbing and storing the releasing carbon from the Java Sea. The present study investigated mangrove above-ground biomass (AGB) and carbon stock in the Karimunjawa-Kemujan Islands, the largest mangrove area in the Karimunjawa Islands. Taking the aerial photos from an Unmanned Aerial Vehicle combined with Global Navigation Satellite System (GNSS) measurements, we generated Digital Surface Model (DSM) and Digital Terrain Model (DTM) with high accuracy. We calculated mangrove canopy height by subtracting DSM from DTM and then converted it into Lorey’s height. The highest mangrove canopy is located along the coastline facing the sea, ranging from 8 m to 15 m. Stunted mangroves 1 m to 8 m in height are detected mainly in the inner areas. AGBs were calculated using an allometric equation destined for the Southeast and East Asia region. Above-ground carbon biomass is half of AGB. The AGB and carbon biomass of mangroves in the Karimunjawa-Kemujan Islands range from 8 Mg/ha to 328 Mg/ha, and from 4 MgC/ha to 164 MgC/ha, respectively. With a total area of 238.98 ha, the potential above-ground carbon stored in the study area is estimated as 16,555.46 Mg.

Spatial distribution of above ground carbon density in Harana Forest, Ethiopia

Background The need for understanding spatial distribution of forest aboveground carbon density (ACD) has increased to improve management practices of forest ecosystems. This study examined spatial distribution of the ACD in the Harana Forest. A grid sampling technique was employed and three nested circular plots were established at each point where grids intersected. Forest-related data were collected from 1122 plots while the ACD of each plot was estimated using the established allometric equation. Environmental variables in raster format were downloaded from open sources and resampled into a spatial resolution of 30 m. Descriptive statistics were computed to summarize the ACD. A Random Forest classification model in the R-software package was used to select strong predictors, and to predict the spatial distribution of ACD. Results The mean ACD was estimated at 131.505 ton per ha in this study area. The spatial prediction showed that the high class of the ACD was confined to eastern and southwest parts of the Harana Forest. The Moran’s statistics depicted similar observations showing the higher clustering of ACD in the eastern and southern parts of the study area. The higher ACD clustering was linked with the higher species richness, species diversity, tree density, tree height, clay content, and SOC. Conversely, the lower ACD clustering in the Harana Forest was associated with higher soil cation exchange capacity, silt content, and precipitation. Conclusions The spatial distribution of ACD in this study area was mainly influenced by attributes of the forest stand and edaphic factors in comparison to topographic and climatic factors. Our findings could provide basis for better management and conservation of aboveground carbon storage in the Harana Forest, which may contribute to Ethiopia’s strategy of reducing carbon emission.

Allometric equations to estimate the leaf area of Psychotria colorata (Willd. Ex Schult.) Müll.Arg.

Estimating leaf area using non-destructive methods from regression equations has become a more efficient, quick, and accurate way. Thus, this study aimed to propose an equation that significantly estimates the leaf area of Psychotria colorata (Rubiaceae) through linear leaf dimensions. For this purpose, 200 leaves of different shapes were collected, and length (L), width (W), product of length by width (L.W), and real leaf area (LA) of each leaf blade were determined. Then, equations were adjusted for predicting leaf area using simple linear, linear (0.0), quadratic, cubic, power, and exponential regression models. The proposed equation was selected according to the coefficient of determination (R²), Willmott's agreement index (d), Akaike's information criterion (AIC), mean absolute error (MAE), mean squared error (RMSE) and BIAS index. It was noted that the equations adjusted using L.W met the best criteria for estimating leaf area, but the equation LA = 0.59 * L.W from linear regression without intercept was the most suitable. This equation predicts that 59% of leaf area is explained by L.W. Concluding, the leaf area of P. colorata can be estimated using an allometric equation that uses linear leaf blade dimensions.

Estimation of the Setting and Infrastructure Criterion of the UI GreenMetric Ranking Using Unmanned Aerial Vehicles

This study presents a methodology to estimate the seven indicators of the Setting and Infrastructure criterion of the UI GreenMetric World University Ranking based on three-dimensional data from a point cloud taken from an unmanned aerial vehicle (UAV). This study also estimated the potential aerial biomass, C and CO2, stored in the green spaces of a university campus using photogrammetric data analyzed in a Geographic Information System (GIS). The method was based on isolating classified point clouds using digital surface models (DSMs) and ground control points (GCPs) considering the canopy height model (CHM), the allometric equation (DBH, p, h), the biomass conversion factor, and carbon dioxide equivalents (CO2-e). The results confirmed that the national models for estimating the potential C reserves in natural forests are very close to reality and that the open space and green areas available to people on campus are adequate. The use of photogrammetric data facilitated the estimation of UI GreenMetric indicators from a highly detailed, low-cost three-dimensional model. The results of a case study revealed that the campus assimilates the CO2 emissions it produces and generates a surplus.

The Moisture Content and Absorption Levels of Carbon Dioxide in Binuang Bini (Octomeles sumatrana Miq) Trees For Climate Change Management

Binuang bini (Octomeles sumatrana Miq) is a fast-growing tree with numerous economic benefits, such as the provision of wood for carpentry purposes, building boards, water management, and absorption of carbon dioxide (CO2). Therefore, this tree species has great potential and needs to be included in Reducing Emission from Deforestation and Forest Degradation (REDD)+'s mitigation program to tackle climate change. In its development, REDD+ has made it possible to carry out carbon trading in the world. Therefore, countries capable of performing protective functions and carry out reforestation, afforestation, and restoration, have the opportunity to be involved in world carbon trading. This study aims to determine the moisture content and carbon absorption rate of Binuang bini trees as a first step to regulate the allometric equation using destructive and laboratory analysis. The results show that the water content in the roots, leaves, as well as the base, middle, and tip of the stem were: 73.69%, 68.39%, 65.59%, 61.22%, and 66.26%, respectively. Furthermore, the sample test results indicate a very close relationship between carbon concentration and absorbance in the O. sumatrana tree with a simple linear regression equation: Y = 0.002X + 0.0593 with R2 = 0.9896. Therefore, this regression equation can be used to calculate the carbon concentration sample for the O. sumatrana tree fraction. The carbon content in 3 tree samples with a breast height diameter of 9.24 cm, 10.08 cm, and 11.68 cm was 2,585 kg. 2,913 kg, and 4,654 kg, respectively. In addition, the carbon sequestration for each tree diameter per year is 1.581 kg year-1, 1,782 kg year-1and 2,847 kg year-1, respectively.

Richesse Floristique Et Stockage De Carbone De La Zone Agricole De La Forêt De Kissila Dans Le Mayombe Congolais

Sustainable forest management remains a major challenge for the international and local community in addressing deforestation and forest degradation. These forests are now experiencing a very marked degradation, mainly caused by agricultural practices. This study assessed the floristic richness and the stock of aerial carbon in order to contribute to a better knowledge of the natural resources of this forest. Five plots of 50m each have been installed with a total area of 12,500m² or 1,25ha. All trees of Diameter to Chest Height (DHP) ≥ 10cm were surveyed at 1.30m from the soil in each plot. Species richness, ecological spectrum, floristic diversity indices, and structural parameters were studied. Above-ground biomass was calculated using Djomo's allometric equation and carbon estimation by above-ground biomass x 0.47. The floristic inventory helped to identify 309 trees that were inventoried, comprising 79 species, 63 genera, and 32 families. The family of Annonaceae (11.39 %) is the most qualitatively represented while that of Olacaceae (11.65%) is the most quantitatively represented. Diversity indices tend to be 5, while density per hectare and average basal area are 247 trees and 10.71 m²/ha. The average calculated aboveground biomass is 311.76tC/ha and the average carbon stock is 89.5tC/ha. This study shows that the forest in this area can be classified as a highly disturbed secondary forest. La gestion durable des forêts reste un problème majeur que doit faire face la communauté internationale et locale dans la lutte contre la déforestation et la dégradation des forêts. Ces forêts connaissent de nos jours une dégradation très accentuée principalement causée par les pratiques agricoles. Cette étude a pour objectif d’évaluer la richesse floristique et d’estimer le stock de carbone aérien afin de contribuer à une meilleure connaissance des ressources naturelles de cette forêt du Mayombe en général et celle du village Kissila en particulier. Cinq parcelles de 50 m de côté chacune ont été installées avec une superficie totale de 12.500 m² soit 1,25 ha. Tous les arbres de Diamètre à Hauteur de la Poitrine (DHP) ≥10 cm ont été inventoriés à 1,30 m du sol dans chaque parcelle. La richesse spécifique, le spectre écologique, les indices de diversité floristique, ainsi que les paramètres structuraux ont été étudiés. La biomasse aérienne a été calculée à partir de l’équation allométrique de Djomo et l’estimation du carbone par la biomasse aérienne x 0,47. L’inventaire floristique a permis d’identifier 309 arbres répartis en 79 espèces, 63 genres et 32 familles. La famille des Annonaceae (11,39 %°) est la plus représentée qualitativement et celle des Olacaceae quantitativement (11,65%). Les indices de diversité de Shannon tendent vers 5, la densité à l’hectare et la surface terrière moyenne sont de 247 arbres et 10,71 m²/ha. La biomasse aérienne moyenne calculée est de 311,76tC/ha et le stock de carbone aérien moyen est de 89,5 tC/ha. Cette étude montre que la forêt de cette zone peut être classée comme une forêt secondaire fortement perturbée.

Estimation of Tree Carbon Stocks in the Green Open Space of the Faculty of Forestry, Tanjungpura University

The presence of green open space containing vegetation in urban areas plays a vital role in absorbing and storing carbon in biomass. Tanjungpura University (Untan) Pontianak has a green open area in the New Building of the Faculty of Forestry. This study aimed to describe carbon reserves stored in biomass above ground level (vegetation) in green open areas around the New Building of Faculty of Forestry Untan Pontianak. Data were collected using an inventory survey by non-destructive sampling, which includes recording with fully enumerated data collection on the type and diameter of trees with a continuous line plot system. The data were then analyzed using allometric equations to obtain biomass values. The results found as many as 56 species of trees with a total of 558 individuals dominated by Litsea garciae and Hevea brasiliensis. The results showed the amount of carbon stored at the tree level of 59.06 tons/ha (76.18%), pole level of 13.94 tons/ha (17.99%), and sapling level of 4.52 tons/ha (5.83%), with an average carbon stock of 77.52 tons/ha. Thus, the green open area could store 148.53 tons of carbon in tree biomass. Although it is a small area, this peatland ecosystem could accumulate peat in organic soil and its vegetation and should be managed as peatland forests. Therefore, proper management is essential, and hydrology management is needed mainly due to its nature. Keywords: allometric equation, biomass, carbon stocks, green open space

Allometric equations for selected Acacia species (Vachellia and Senegalia genera) of Ethiopia

Background Allometric equations are used to estimate biomass and carbon stock of forests. In Ethiopia, despite the presence of large floral diversity, only a few site-specific allometric equations have been developed so far. This study was conducted in the Omo-Gibe woodland of south-western Ethiopia to develop an allometric equation to estimate the Above-ground Biomass (AGB) of the four Acacia species (Senegalia polyacantha, Vachellia seyal, Vachellia etbaica and Vachellia tortilis). Fifty-four (54) Acacia trees were sampled and measured within 35 temporarily established square plots. In each plot, dendrometric variables were measured to derive the models based on combinations of Diameter at Breast Height (DBH), height, and wood density as predictor variables. Model performance was evaluated using goodness-of-fit statistics. The biomass was compared using four allometric biomass models that have been widely used in the tropics. Results The model containing DBH alone was more accurate to estimate AGB compared to the use of multiple predictor variables. This study, therefore, substantiated the importance of site-specific allometric equations in estimating the AGB of Acacia woodlands. This is because a site-specific allometric equation recognizes the environmental factors, vegetation types and management practices. Conclusions The results of this study contribute to a better understanding of allometric equations and an accurate estimate of AGB of Acacia woodlands in Ethiopia and similar ecosystems elsewhere.

Allometric equation of local bamboo for estimating carbon sequestration of bamboo riparian forest

The cause of global warming is the increasing carbon concentration arising from industrial activities, burning of fossils, and land-use change. The purpose of this research was to find out the allometric equation to calculate the local bamboo biomass and then to be able to calculate how much carbon sequestration at bamboo riparian forest since this area was rarely being explored. The parameters observed were the height and diameter of the bamboo stem at 1.3 m height of 6 types of local bamboo using destructive sampling, along with the measurement of bamboo weight. The carbon content of the bamboo biomass, litter, and soil was measured to complement the estimation of total carbon sequestration. The results showed that the allometric equation for estimating local bamboo biomass is Y=0.6396 X1.6162 with R2=0.77, obtained from the relationship equations between dry weight and the diameter. Total carbon sequestration of this system ranged between 81 to 215 tons C ha−1.

Biomass Production and Nutrient Accumulation by Natural Rubber (Hevea brasiliensis Wild. Ex A. Juss.) Müell. Arg. Clones in a Humid Tropical Area in South India

Natural rubber (Hevea brasiliensis Wild. Ex A. Juss.) Müell. Arg. is an important commodity crop grown in world over for industrial raw material rubber latex for various products, mainly tyre manufacturing. Hevea propagation is through clones evolved by breeding as cultivars with desired characters. This article presented the biomass and nutrient accumulation of four important Hevea clones viz. RRII 105, RRII 118, RRII 203 and GT1 at 30 years age. Biomass and nutrient concentration of tree components viz. trunk, branches, leaf and root were assessed by uprooting the trees in the field and standing trees using allometric equation. Among the different clones, RRII 118 and GT1 recorded higher biomass compared to RRII 105 and RRII 203. Above-ground biomass (88-93 per cent) varied more than below-ground biomass (7-11 per cent). The high yielding clones had higher leaf and root biomass. Drought tolerant and timber clones viz. RRII 118 and RRII 203 recorded higher K and high yielding clone RRII 105 had higher Ca accumulation. Biomass removal of these clones may lead to deficiency of K and Ca in soil and hence needs the external supplements. The relation of high Ca content and leaf disease of fungal origin is promising for further studies. The higher accumulation of iron and manganese indicated the tolerance of Hevea to these elements and possibility of phytoremediation. The per cent contribution of nutrients to total biomass varied less between clones and was below 3 percent at the age of 30 years and this is evidence of adjustments in proportions of nutrients in Hevea irrespective of clonal variations.