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

2021 ◽  
Vol 17 (40) ◽  
pp. 1
Author(s):  
Luc Kimpolo ◽  
Saint Fédriche Ndzai, ◽  
Félix Koubouana
Keyword(s):  
Local Community ◽  
Sustainable Forest Management ◽  
Secondary Forest ◽  
Structural Parameters ◽  
Basal Area ◽  
Forest Degradation ◽  
Diversity Indices ◽  
Allometric Equation ◽  
Above Ground Biomass ◽  
Ground Biomass

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.

Using photography to estimate above-ground biomass of small trees

2020 ◽  
pp. 1-7
Author(s):  
Brandon R. Hays ◽  
Corinna Riginos ◽  
Todd M. Palmer ◽  
Benard C. Gituku ◽  
Jacob R. Goheen
Keyword(s):  
Cost Effective ◽  
Allometric Equation ◽  
Biomass Estimation ◽  
Above Ground Biomass ◽  
Tree Biomass ◽  
East African ◽  
Ground Biomass ◽  
Herbivore Exclusion ◽  
Significant Difference ◽  
Allometric Relation

Abstract Quantifying tree biomass is an important research and management goal across many disciplines. For species that exhibit predictable relationships between structural metrics (e.g. diameter, height, crown breadth) and total weight, allometric calculations produce accurate estimates of above-ground biomass. However, such methods may be insufficient where inter-individual variation is large relative to individual biomass and is itself of interest (for example, variation due to herbivory). In an East African savanna bushland, we analysed photographs of small (<5 m) trees from perpendicular angles and fixed distances to estimate above-ground biomass. Pixel area of trees in photos and diameter were more strongly related to measured, above-ground biomass of destructively sampled trees than biomass estimated using a published allometric relation based on diameter alone (R2 = 0.86 versus R2 = 0.68). When tested on trees in herbivore-exclusion plots versus unfenced (open) plots, our predictive equation based on photos confirmed higher above-ground biomass in the exclusion plots than in unfenced (open) plots (P < 0.001), in contrast to no significant difference based on the allometric equation (P = 0.43). As such, our new technique based on photographs offers an accurate and cost-effective complement to existing methods for tree biomass estimation at small scales with potential application across a wide variety of settings.

scholarly journals Forest Structure, Composition and Above Ground Biomass of Tree Community in Tropical Dry Forests of Eastern Ghats, India

2016 ◽  
Vol 8 (1) ◽  
pp. 125-133 ◽  
Author(s):  
Sudam Charan SAHU ◽  
H.S. SURESH ◽  
N.H. RAVINDRANATH
Keyword(s):  
Forest Structure ◽  
Tree Species ◽  
Basal Area ◽  
Eastern Ghats ◽  
Tropical Dry Forests ◽  
Above Ground Biomass ◽  
Importance Value ◽  
Shorea Robusta ◽  
Ground Biomass ◽  
C Stocks

The study of biomass, structure and composition of tropical forests implies also the investigation of forest productivity, protection of biodiversity and removal of CO2 from the atmosphere via C-stocks. The hereby study aimed at understanding the forest structure, composition and above ground biomass (AGB) of tropical dry deciduous forests of Eastern Ghats, India, where as a total of 128 sample plots (20 x 20 meters) were laid. The study showed the presence of 71 tree species belonging to 57 genera and 30 families. Dominant tree species was Shorea robusta with an importance value index (IVI) of 40.72, while Combretaceae had the highest family importance value (FIV) of 39.01. Mean stand density was 479 trees ha-1 and a basal area of 15.20 m2 ha-1. Shannon’s diversity index was 2.01 ± 0.22 and Simpson’s index was 0.85 ± 0.03. About 54% individuals were in the size between 10 and 20 cm DBH, indicating growing forests. Mean above ground biomass value was 98.87 ± 68.8 Mg ha-1. Some of the dominant species that contributed to above ground biomass were Shorea robusta (17.2%), Madhuca indica (7.9%), Mangifera indica (6.9%), Terminalia alata (6.9%) and Diospyros melanoxylon (4.4%), warranting extra efforts for their conservation. The results suggested that C-stocks of tropical dry forests can be enhanced by in-situ conserving the high C-density species and also by selecting these species for afforestation and stand improvement programs. Correlations were computed to understand the relationship between above ground biomass, diversity indices, density and basal area, which may be helpful for implementation of REDD+ (reduce emissions from deforestation and forest degradation, and foster conservation, sustainable management of forests and enhancement of forest carbon stocks) scheme.

scholarly journals Estimation of Forest Above-Ground Biomass by Geographically Weighted Regression and Machine Learning with Sentinel Imagery

Forests ◽  
2018 ◽  
Vol 9 (10) ◽  
pp. 582 ◽  
Author(s):  
Lin Chen ◽  
Chunying Ren ◽  
Bai Zhang ◽  
Zongming Wang ◽  
Yanbiao Xi
Keyword(s):  
Machine Learning ◽  
Geographically Weighted Regression ◽  
Prediction Models ◽  
Forest Degradation ◽  
Weighted Regression ◽  
Changbai Mountains ◽  
Support Vector ◽  
Above Ground Biomass ◽  
Ground Biomass ◽  
Texture Characteristics

Accurate forest above-ground biomass (AGB) is crucial for sustaining forest management and mitigating climate change to support REDD+ (reducing emissions from deforestation and forest degradation, plus the sustainable management of forests, and the conservation and enhancement of forest carbon stocks) processes. Recently launched Sentinel imagery offers a new opportunity for forest AGB mapping and monitoring. In this study, texture characteristics and backscatter coefficients of Sentinel-1, in addition to multispectral bands, vegetation indices, and biophysical variables of Sentinal-2, based on 56 measured AGB samples in the center of the Changbai Mountains, China, were used to develop biomass prediction models through geographically weighted regression (GWR) and machine learning (ML) algorithms, such as the artificial neural network (ANN), support vector machine for regression (SVR), and random forest (RF). The results showed that texture characteristics and vegetation biophysical variables were the most important predictors. SVR was the best method for predicting and mapping the patterns of AGB in the study site with limited samples, whose mean error, mean absolute error, root mean square error, and correlation coefficient were 4 × 10−3, 0.07, 0.08 Mg·ha−1, and 1, respectively. Predicted values of AGB from four models ranged from 11.80 to 324.12 Mg·ha−1, and those for broadleaved deciduous forests were the most accurate, while those for AGB above 160 Mg·ha−1 were the least accurate. The study demonstrated encouraging results in forest AGB mapping of the normal vegetated area using the freely accessible and high-resolution Sentinel imagery, based on ML techniques.

Allometric relationships and community biomass estimates for some dominant eucalypts in Central Queensland woodlands

2000 ◽  
Vol 48 (6) ◽  
pp. 707 ◽  
Author(s):  
W. H. Burrows ◽  
M. B. Hoffmann ◽  
J. F. Compton ◽  
P. V. Back ◽  
L. J. Tait
Keyword(s):  
Basal Area ◽  
Carbon Stocks ◽  
Allometric Equations ◽  
Allometric Relationships ◽  
Above Ground Biomass ◽  
Greenhouse Gas Inventory ◽  
Individual Tree ◽  
Ground Biomass ◽  
Eucalyptus Crebra ◽  
The Mean

Allometric equations are presented relating stem circumference to branch, leaf, trunk, bark, total above-ground and lignotuber biomass for Eucalyptus crebra F.Muell. (woodland trees), E. melanophloia Sol. Ex Gaerth. (both woodland and regrowth community trees) and E. populnea F.Muell. (woodland trees). There were no significant differences (P > 0.05) between the slopes of individual lognormal regression lines plotting stem circumference against total above-ground biomass for E. crebra, E. melanophloia and E. populnea. Root-to-shoot ratios and leaf area indices were also determined for the stands contributing to each regression. The regressions were then applied to measured eucalypt stems in the associated plant community to give estimates of each stand’s component (eucalypt tree fraction only) biomass per hectare. These eucalypt regressions were next applied to measured stems of each species on a total of 33 woodland sites in which these eucalypts individually contributed > 75% of total site basal area. Above-ground biomass/basal area relationships averaged 6.74 0.29 t m–2 basal area for 11 E. crebra sites, 5.11 0.28 t m–2 for 12 E. melanophloia sites and 5.81 0.11 t m–2 for 10 E. populnea sites. The mean relationship for all sites was 5.86 0.18 t m–2 basal area. The allometric relationships presented at both individual tree and stand levels, along with calculated biomass : basal area relationships, enable ready estimates to be made of above-ground biomass (carbon stocks) in woodlands dominated by these eucalypts in Queensland, assuming individual stem circumferences or community basal areas are known. However, to document changes in carbon stocks (e.g. for Greenhouse Gas Inventory or Carbon Offset trading purposes), more attention needs to be placed on monitoring fluxes in the independent variables (predictors) of these allometric equations.

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

2022 ◽  
Vol 14 (2) ◽  
pp. 706
Author(s):  
Anindya Wirasatriya ◽  
Rudhi Pribadi ◽  
Sigit Bayhu Iryanthony ◽  
Lilik Maslukah ◽  
Denny Nugroho Sugianto ◽  
...  
Keyword(s):  
Unmanned Aerial Vehicle ◽  
Carbon Stock ◽  
Digital Terrain Model ◽  
Satellite System ◽  
Allometric Equation ◽  
Surface Model ◽  
Above Ground Biomass ◽  
Ground Biomass ◽  
Carbon Biomass ◽  
Aerial Vehicle

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.

Controls of plant diversity attributes over above ground biomass in Sal forests of Eastern India

2020 ◽  
Author(s):  
Rahul Kumar ◽  
Amit Kumar ◽  
Purabi Saikia
Keyword(s):  
Climate Change ◽  
Carbon Sequestration ◽  
Plant Diversity ◽  
Global Climate ◽  
Basal Area ◽  
Above Ground Biomass ◽  
Eastern India ◽  
Shorea Robusta ◽  
Ground Biomass ◽  
Indian Forests

Abstract Background Above ground biomass (AGB) is a useful measure for assessing changes in forest structure and functional, and play a significant role in studying carbon stocks, the effect of deforestation and carbon sequestration on the global carbon balance. The present study aimed to study the relationship between AGB and community parameters in Sal forests of Eastern India through stratified random sampling by lying 92 belt transects each of 0.5 ha size. Results It recorded a high AGB (410.70 Mg ha-1), and carbon stock (Cp) (193.06 Mg C ha-1), and forest wise AGB ranged from 0.19 to 24.75 Mg ha-1 (mean 4.45 ± 0.45 SE). The spatial pattern of AGB showed that maximum studied forests (65%) had very low AGB (<5.00 Mg ha-1), and only one forests (1%) located in the northwest corner of Ranchi had very high AGB (>20 Mg ha-1). Species wise AGB ranged from 0.001 to 7074.94 Mg ha-1 (mean 106 ± 71 SE) and Shorea robusta with maximum basal area (120.81 m2 ha−1) contributed maximum AGB (64.87% of the total AGB), however, no similar trends have been observed in any other tree species. A significant positive correlation was observed between AGB and Cp (r=1.00, p<0.01), H’ (r= .58, p<0.01), Dmg (r= .31, p<0.01), Dmn (r= .49, p<0.01), ENS (r= .57, p<0.01), E (r= .26, p<0.05), and basal area (r= 0.71, p<0.05). However, a negative correlation of AGB was evident with CD (r= -.57, p<0.01), and density (r= - 0.17). Conclusions The relationships differed greatly among plant diversity attributes, basal area, density, AGB, and Cp within and among various forests and the strongest relationships within each forests were always those having greater richness (Dmg, Dmn), diversity (H, ENS), basal area or evenness (E). Estimation of forest Cp enables us to assess the amount of carbon loss during deforestation or the amount of carbon stored during forest regeneration. The present study will directly help in studying the response of climate change on ecosystem productivity, energy and nutrient flow, and for assessing the patterns of carbon sequestration in Indian forests under global climate change.

scholarly journals Uneven-aged silviculture of Scots pine in Bohemia and Central Spain: comparison study of stand reaction to transition and long-term selection management

2020 ◽  
Vol 66 (No. 1) ◽  
pp. 22-35 ◽  
Author(s):  
Josef Gallo ◽  
Lukáš Bílek ◽  
Václav Šimůnek ◽  
Sonia Roig ◽  
José Alfredo Bravo Fernández
Keyword(s):  
Scots Pine ◽  
Sustainable Forest Management ◽  
Environmental Changes ◽  
Basal Area ◽  
Diversity Indices ◽  
Mountain Range ◽  
Central Spain ◽  
Ecological Requirements ◽  
Intensively Managed

The achievement of sustainable forest management requires the incorporation of ongoing environmental changes into long-term planning. Moreover, in time of climatic change and changing company demands, importance of Scots pine (Pinus sylvestris L.) is still increasing at the expense of other tree species due to its low ecological requirements. The aim of the study was to compare the structure and production of Scots pine stands managed under different silvicultural systems on four research plots, assess the structural and diversity indices, and analyse the increment structure using tree-ring dating in the Czech Republic and Spain. Area of study was Western Bohemian and Guadarrama Mountain range in Central Spain. The results indicate that stand volume on the investigated plots ranged from 231 to 441 m<sup>3</sup>∙ha<sup>–1</sup> with tree density 276–996 trees∙ha<sup>–1</sup>. Intensively managed (uneven-aged) permanent research plots showed increased growth on basal area. The difference was evident also for older trees. The transition to uneven-aged forest does not negatively influence stocking and wood production and provide higher benefits for diversity and structural complexity in comparison to regular stands.

scholarly journals Estimation of above-ground biomass in forest stands from regression on their basal area and height

2016 ◽  
Vol 64 (1) ◽  
pp. 70-92 ◽  
Author(s):  
Mait Lang ◽  
Ando Lilleleht ◽  
Mathias Neumann ◽  
Karol Bronisz ◽  
Samir G. Rolim ◽  
...  
Keyword(s):  
Regression Models ◽  
Measurement Data ◽  
Basal Area ◽  
Growth Conditions ◽  
Repeated Measurements ◽  
Carbon Accounting ◽  
Published Data ◽  
Above Ground Biomass ◽  
Forest Stands ◽  
Ground Biomass

Abstract A generic regression model for above-ground biomass of forest stands was constructed based on published data (R2 = 0.88, RSE = 32.8 t/ha). The model was used 1) to verify two allometric regression models of trees from Scandinavia applied to repeated measurements of 275 sample plots from database of Estonian Network of Forest Research (FGN) in Estonia, 2) to analyse impact of between-tree competition on biomass, and 3) compare biomass estimates made with different European biomass models applied on standardized forest structures. The model was verified with biomass measurements from hemiboreal and tropical forests. The analysis of two Scandinavian models showed that older allometric regression models may give biased estimates due to changed growth conditions. More biomass can be stored in forest stands where competition between trees is stronger. The tree biomass calculation methods used in different countries have also substantial influence on the estimates at stand-level. A common database of forest biomass measurements from Europe in similar to pan-tropical tree measurement data may be helpful to harmonise carbon accounting methods.

scholarly journals Diversity, Population Structure, and Above Ground Biomass in Woody Species on Ngomakurira Mountain, Domboshawa, Zimbabwe

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Clemence Zimudzi ◽  
Christopher Chapano
Keyword(s):  
Small Diameter ◽  
Basal Area ◽  
Woody Species ◽  
Distribution Patterns ◽  
Wiener Index ◽  
Mean Value ◽  
Stem Density ◽  
Above Ground Biomass ◽  
Systematic Random Sampling ◽  
Ground Biomass

The diversity, structure, species composition, and above ground biomass of woody plants on Ngomakurira mountain in Zimbabwe were studied. A systematic random sampling approach was adopted to establish 52 sampling plots measuring 10 × 10 m across 3 study strata in the 1266 ha study area. Woody species occurring in each plot were identified and the circumferences of trees with diameters >8.0 cm at 1.3 m height were measured. A total of 91 species belonging to 74 genera and 39 families were identified in the sample plots. A Shannon-Wiener index mean value of 3.12 was obtained indicating high species diversity on the mountain. The DBH size class distribution showed inverse J distribution patterns across the three study strata, but with only 3 individual plants with DBH > 30 cm. Mean basal area was 15.21 m2 ha−1 with U. kirkiana and J. globiflora contributing approximately 30% of the basal area. The estimated above ground biomass ranged from 34.5 to 65.1 t ha−1. Kruskal-Wallis-H test showed no significant differences in species richness, stem density, basal area, above ground biomass, and evenness, across the study strata (p<0.05). Ngomakurira woodland has potential to regenerate due to the presence of many stems in the small diameter size classes.

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