Modeling of aboveground tree stand-level biomass in Erukot Forest of Oban Division, Cross River National Park, Nigeria

2021 ◽  
Vol 18 (1) ◽  
Author(s):  
S.E. Bassey ◽  
S. Ajayi
Keyword(s):  
Carbon Dioxide ◽  
Aboveground Biomass ◽  
National Park ◽  
Basal Area ◽  
Tree Stand ◽  
Diameter At Breast Height ◽  
Total Height ◽  
Breast Height ◽  
Dry Biomass ◽  
Individual Trees

This research estimated aboveground tree stand level Biomass in Erukot Forest of Oban Division, Cross River National Park. A total of 872 individual trees were identified and measured for diameter at breast height and total height (dbh ≥ 5cm). The 872 individual trees spread across 51 species belonging to 25 different tree families. Simple random sampling was used with sampling intensity of 0.3% to lay 15 nested plots (7m x 7m, 25m x 25m and 35m x 35m). Diameter at breast height, total height and specific density of each wood species were used to determine aboveground biomass for each tree. Conversion factors were applied to estimate stand level green and dry biomass, sequestered carbon and carbon dioxide (CO2) emission in the study area. Simple linear regression models were fitted into the stand level growth data for the forest (basal area and volume). The mean diameter at breast height and mean total height were 38.5cm and 18.5m respectively. Mean basal area of 39.8 m2 ha-1 was obtained with a mean volume of 177.3 m3 ha-1 . Average green biomass, dry biomass, carbon stock and carbon-dioxide emission of 521.8113 ton ha-1 , 341.5880 ton ha-1 , 183.196 ton ha-1 and 694.2067 ton ha-1 respectively were obtained in the study area. Stand level biomass model developed for the forest showed that common logarithm of volume per hectare is significantly related to common logarithm of stand biomass (R2 = 58%). The actual and predicted biomasses were not significantly different (Paired T-test at p ˂ 0.05). Estimated bias of 0.10% for the stand biomass model means that the developed model can be used to predict the aboveground biomass of the study area without any adjustment. The research has provided easy to use regression model for determining aboveground biomass at stand level. This is very useful for carbon trade and assessment of carbon-dioxide emissions through deforestation in the study area. The model is also a tool for assessing the wood productivity of the study area and for better management of the park. Keyword: Sequestered carbon, aboveground biomass, dry biomass, conversion factor

scholarly journals BIOMASS EQUATIONS FOR CAATINGA SPECIES

Nativa ◽  
2018 ◽  
Vol 6 (5) ◽  
pp. 517
Author(s):  
Mayara Dalla Lana ◽  
Rinaldo Luiz Caraciolo Ferreira ◽  
José Antônio Aleixo da Silva ◽  
Gustavo Pereira Duda ◽  
Carlos Frederico Lins e Silva Brandão ◽  
...  
Keyword(s):  
Aboveground Biomass ◽  
Total Biomass ◽  
Good Precision ◽  
Diameter At Breast Height ◽  
Total Height ◽  
Breast Height ◽  
Biomass Equations ◽  
Statistical Criteria ◽  
Aspidosperma Pyrifolium ◽  
Mimosa Tenuiflora

EQUAÇÕES DE BIOMASSA PARA ESPÉCIES DA CAATINGA O objetivo deste trabalho foi determinar as proporções de fuste, galhos e folhas em relação a biomassa total seca acima do solo e ajustar modelos estatísticos para estimativa da biomassa das principais espécies arbustivo-arbóreas em uma área de Caatinga. O número de indivíduos abatidos e com a biomassa aérea total determinada foi de 15 para Anadenanthera colubrina, Aspidosperma pyrifolium, Cnidoscolus quercifolius, Mimosa ophthalmocentra, Mimosa tenuiflora, Poincianella bracteosa e, de 30 para Bauhinia cheilantha e Croton heliotropiifolius. Para ajuste dos modelos foram utilizados os dados de biomassa total seca acima do solo coletados como variável dependente e as variáveis independentes foram o diâmetro à altura do peito e a altura total dos indivíduos por espécie. Foram testados oito modelos para cada uma das espécies e para todas as espécies agrupadas. Para a seleção da melhor equação utilizou-se os tradicionais critérios estatísticos. As proporções de biomassa das espécies foram quantificadas, tanto para os seus compartimentos, quanto para o total e apresentaram uma grande variação entre espécies e indivíduos da mesma espécie. Equações de biomassa aérea seca foram ajustadas com boas estatísticas de precisão, podendo ser utilizadas para a sua estimativa de biomassa de maneira confiável em regiões de Caatinga.Palavras-chave: Análise de regressão, diâmetro à altura do peito, altura total. ABSTRACT:The objective of this work was to determine the proportions of stem, branches and leaves in relation to total dry aboveground biomass and adjust statistical models to estimate the biomass of the main species in an area of Caatinga. The number of trees cut and with the determined total aboveground biomass was 15 for Anadenanthera colubrina, Aspidosperma pyrifolium, Cnidoscolus quercifolius, Mimosa ophthalmocentra, Mimosa tenuiflora, and Poincianella bracteosa, and 30 for Bauhinia cheilantha and Croton heliotropiifolius. The data of total dry aboveground biomass were used as dependent variables and the diameter at breast height and total height of individuals per species were used as the independent variables for adjusting the models. Eight models were tested for each species and for all grouped species. Traditional statistical criteria was used for selecting the best equation. The proportions of the species were quantified for both their biomass compartments and for the total biomass, showing great variation between species and individuals of the same species. Dry aboveground biomass equations were developed with good precision statistics and can therefore be used for estimating biomass in Caatinga regions.Keywords: Regression analysis, diameter at breast height, total height.

scholarly journals Importance of dead wood resources for woodpeckers in coniferous stands of the Białowieża Forest

2012 ◽  
Vol 23 (4) ◽  
pp. 414-425 ◽  
Author(s):  
DOROTA CZESZCZEWIK ◽  
WIESŁAW WALANKIEWICZ ◽  
CEZARY MITRUS ◽  
TOMASZ TUMIEL ◽  
TOMASZ STAŃSKI ◽  
...  
Keyword(s):  
National Park ◽  
Dead Wood ◽  
Nature Reserve ◽  
Basal Area ◽  
Tree Stand ◽  
Białowieża Forest ◽  
Breast Height ◽  
Dead Trees ◽  
Different Types ◽  
Standing Trees

SummaryMany woodpecker species are known to be sensitive to the removal of dead wood. In 1999–2001 and 2007–2009 woodpeckers and dead wood abundance were studied in coniferous stands of the Białowieża Forest, Poland. Transects (3.9–6 km long) were established in three zones of different types of management: 1) primeval, unmanaged stands (BNP); 2) partially managed nature reserve (RES); 3) heavily managed stands (MAN). Woodpeckers were counted along transects three times per season, and tree stand measurements (number of standing and fallen trees, diameter at breast height, volume of fallen logs) were made once every three years. Woodpecker indices were highest in BNP and lowest in RES in both three-year study periods. The highest number of species (seven) was recorded in RES. Indices of four woodpeckers including two focal species (Three-toed Woodpecker Picoides tridactylus and White-backed Woodpecker Dendrocopos leucotos) were dependent on the basal area of dead standing trees. The same relation was found for the whole woodpecker assemblage. The highest indices were recorded in BNP, where the highest density of dead standing trees was recorded, and the lowest in the MAN transect with the lowest density of dead trees. However in the RES plot the amount of dead wood was much lower than in the national park. We recommend that the management regulations in Polish nature reserves be changed. In coniferous reserves, it would be best to leave at least 2 m2 ha-1 (basal area) of freshly killed spruce Picea sp. after each bark beetle outbreak.

scholarly journals Woody Species Structure and Regeneration Status in Kafta Sheraro National Park Dry Forest, Tigray Region, Ethiopia

2020 ◽  
Vol 2020 ◽  
pp. 1-22
Author(s):  
Fitsum Temesgen ◽  
Bikila Warkineh
Keyword(s):  
National Park ◽  
Gold Mining ◽  
Basal Area ◽  
Woody Species ◽  
Dry Forest ◽  
Importance Value ◽  
Mature Trees ◽  
Individual Tree ◽  
Diameter At Breast Height ◽  
Breast Height

The study was conducted in Kafta Sheraro National Park (KSNP) dry woodland natural forest located in Kafta Humera and Tahitay Adiyabo weredas (districts), Western and Northwestern Zones of Tigray regional governmental state, North Ethiopia. The objective of the study was to explore the floristic composition, structure, and regeneration of woody species in the home of Loxodonta africana L., Hippotragus equinus, Anthropoides virgo, Ourebia ourebi, Crocuta crocuta, Tragelaphus strepsiceros, Phacochoerus africanus, and unidentified crocodile and fish species. In the park, the vegetation ecology has not been studied up to date which is necessary for conservation. The systematic sampling technique was used to collect vegetation and human disturbance (presence and absence) data from August to December 2018. The vegetation data were collected from 161 plots each with a size of 400 m2 (20 m × 20 m) for tree/shrub while subplots of size 100 m2 (10 m × 10 m) and 25 m2 (5 m × 5 m) for sapling and seedling, respectively, were established in the main plots. Individual tree and shrub diameter at breast height (DBH) ≥2.5 cm and height ≥ 2 m were measured using tape meter and clinometer, respectively. Diameter at breast height (DBH), frequency, density, basal area, and importance value index (IVI) were used for vegetation structure description while the density of mature trees, sapling, and seedling was used for regeneration. A total of 70 woody species (46 (65.7%) trees, 18 (25.7%) shrubs, and 6 (8.6%) tree/shrub) were identified. The total basal area and density of 79.3 ± 4.6 m2·ha−1 and 466 ± 12.8 stems·ha−1, respectively, were calculated for 64 woody species. Fabaceae was the most dominant family with 16 species (22.9%) followed by Combretaceae with 8 species (11.4%). The most dominant and frequent species throughout the park were Acacia mellifera, Combretum hartmannianum, Terminalia brownii, Balanites aegyptiaca, Dichrostachys cinerea, Acacia senegal, Acacia oerfota, Boswellia papyrifera, Ziziphus spina-christi, and Anogeissus leiocarpus. Abnormal patterns of selected woody species were dominantly identified. The regenerating status of all the woody plant species was categorized as “fair” (18.75%), “poor” (7.81%), and “none” (73.44%). There was a significant correlation between altitude, anthropogenic disturbance (grazing and fire frequency), and density of seedling, sapling, and mature trees. But there was no correlation between gold mining and regeneration population. However, there is a good initiation for the conservation of the park; still, the vegetation of the park was threatened by human-induced fire following intensive farming, gold mining, and overgrazing. Therefore, the study area was the habitat for the population of the African elephant; species with low importance value indices and lack or having few seedling and sapling stage should be prioritized for conservation, and their soil seed banks should be studied further.

scholarly journals Seemingly Unrelated Mixed-Effects Biomass Models for Black Locust in West Poland

Forests ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 380
Author(s):  
Karol Bronisz ◽  
Szymon Bijak ◽  
Rafał Wojtan ◽  
Robert Tomusiak ◽  
Agnieszka Bronisz ◽  
...  
Keyword(s):  
Black Locust ◽  
Random Effect ◽  
Tree Height ◽  
Cross Model ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Dependent Variables ◽  
Dry Biomass ◽  
Biomass Components ◽  
Independent Variable

Information about tree biomass is important not only in the assessment of wood resources but also in the process of preparing forest management plans, as well as for estimating carbon stocks and their flow in forest ecosystems. The study aimed to develop empirical models for determining the dry mass of the aboveground parts of black locust trees and their components (stem, branches, and leaves). The research was carried out based on data collected in 13 stands (a total of 38 sample trees) of black locust located in western Poland. The model system was developed based on multivariate mixed-effect models using two approaches. In the first approach, biomass components and tree height were defined as dependent variables, while diameter at breast height was used as an independent variable. In the second approach, biomass components and diameter at breast height were dependent variables and tree height was defined as the independent variable. Both approaches enable the fixed-effect and cross-model random-effect prediction of aboveground dry biomass components of black locust. Cross-model random-effect prediction was obtained using additional measurements of two extreme trees, defined as trees characterized by the smallest and largest diameter at breast height in sample plot. This type of prediction is more precise (root mean square error for stem dry biomass for both approaches equals 77.603 and 188.139, respectively) than that of fixed-effects prediction (root mean square error for stem dry biomass for both approaches equals 238.716 and 206.933, respectively). The use of height as an independent variable increases the possibility of the practical application of the proposed solutions using remote data sources.

scholarly journals Aboveground Biomass Stockpile of Trees in Vallanadu Blackbuck Sanctuary, Peninsular India

2021 ◽  
Vol 16 (3) ◽  
pp. 755-763
Author(s):  
M. Nagaraj M. Nagaraj ◽  
M. Udayakumar
Keyword(s):  
Aboveground Biomass ◽  
Tamil Nadu ◽  
Basal Area ◽  
Single Species ◽  
Forest Tree ◽  
Annual Rainfall ◽  
Dry Forests ◽  
Peninsular India ◽  
Tree Inventory ◽  
Individual Trees

A forest tree inventory study was conducted in Vallanadu Black buck sanctuary, Tuticorin. The current study was conducted to assess tree density, species richness, basal area (BA) and aboveground biomass (AGB) stockpile. The study area has been classified as Southern Thorn Forest (SFT). One hundred square plots (total area 1 ha), each 10m × 10m (100 m2 each) laid randomly across study area. All live trees with ≥5 cm diameter at breast height (DBH) measured at 137 cm above the ground. As the whole, 1335 individual trees ≥5cm DBH recorded. A total number of 18 species recorded from 14 genera and 11 families in study area. The family Mimosaceae has maximum number of species (7 species) followed by Rhamnaceae (2 species), while 9 families had just single species’ each. The total basal area recorded was 22.046 m2 ha-1, while, the mean wood density (WD) of trees estimated as 0.70±0.093 g cm-3. Total amount of 50.065 Mg ha-1 present in STF. The contribution of different species in terms of total AGB varied significantly. Commiphora berryi stocked 45.13% (22.588 Mg ha-1) of AGB followed by A. planifrons (23.31%, 11.669 Mg ha-1), A. mellifera (7.233%, 3.621 Mg ha-1), whereas remaining 15 species collectively stocked 24.327% (12.187 Mg ha-1) AGB. The STF had a large number of trees compared to some dry forests within Tamil Nadu. Southern Thorn Forest endowed with a moderate number of trees species. Aboveground biomass stockpile of trees is comparable with the range recorded from Indian dry forests. The study area experiences lesser mean annual rainfall and >6 months dry season. Further, endowed with short-bole and smaller leaved trees, hence stocked a relatively lesser AGB in trees.

scholarly journals Predicting Total Height from Diameter Using Nonlinear Models in Pinus roxburghii

2013 ◽  
Vol 14 (1) ◽  
pp. 147-152
Author(s):  
TB Thapa ◽  
CP Upadhyaya ◽  
YP Timilsina ◽  
SK Bhandari ◽  
L Puri
Keyword(s):  
Nonlinear Models ◽  
Productive Capacity ◽  
Test Statistics ◽  
Pinus Roxburghii ◽  
Diameter At Breast Height ◽  
Total Height ◽  
Breast Height ◽  
Research Activities ◽  
Chir Pine ◽  
Desirable Behavior

Height of the trees is not only used to estimate the product available from trees and to determine the productive capacity of the particular land but also used in forest management and research activities. In this research, predictability of total height from diameter at breast height for chir-pine (Pinus roxburghii) by using nonlinear models was examined. Total height and diameter at breast height of 180 trees were measured by using Suunto Clinometer and diameter tape respectively. The measured data were subjected to previously developed robust and strong statistical models, and evaluated by using different test statistics. Among those, H = e(-0.276) D0.925 explained the greatest proportion of variations of height (R2adj.=0.910) and minimum root mean square error (RMSE=1.221) and showed desirable behavior of flexibility and robustness. Nepal Journal of Science and Technology Vol. 14, No. 1 (2013) 147-152 DOI: http://dx.doi.org/10.3126/njst.v14i1.8935

Biogenic Imprint on Hillslopes in the Sudety Mts. — Origin and Consequences of the Tree Uprooting Process

2014 ◽  
Vol 48 (1) ◽  
Author(s):  
Łukasz Pawlik
Keyword(s):  
National Park ◽  
Qualitative Description ◽  
Main Subject ◽  
Diameter At Breast Height ◽  
Geomorphological Mapping ◽  
Breast Height ◽  
The World ◽  
The Mean ◽  
Tree Uprooting ◽  
Root Plate

AbstractThe main subject of this article is the tree uprooting process and its effects on forested hillslopes in the Sudety Mts. The research has been carried out between 2010 and 2012 in the Karkonosze National Park (KNP), Stołowe Mountains National Park (SMNP) and Suche Mts. The methods included: detailed geomorphological mapping and measurements of root plates of recently fallen trees and relict treethrow mounds and pits (called pit-and-mound microtopography), their qualitative description and measurements of diameter at breast height (dbh) of uprooted tree trunks.The mean root plate volume was 0.3-1.4 mIt has been shown that tree uprooting can contribute to the evolution of regolith and soils and it is an important factor of their disturbances. This reflects results from other sites in the World. However, in the Sudety Mts. the significance of tree uprooting has been validated only locally and it is suggested that its importance decreases proportionally to the area under consideration. Here, biogenic transport is limited to treethrow pits on gentle hillslopes but can be much more effective at steeper sites.

Modelling survival probability of individual trees in Norway spruce stands under different thinning regimes

2005 ◽  
Vol 35 (1) ◽  
pp. 113-121 ◽  
Author(s):  
Kjell Karlsson ◽  
Lennart Norell
Keyword(s):  
Norway Spruce ◽  
Goodness Of Fit ◽  
Basal Area ◽  
Site Index ◽  
Stand Age ◽  
Goodness Of Fit Test ◽  
Individual Tree ◽  
Thinning Intensity ◽  
Diameter At Breast Height ◽  
Breast Height

The probability that an individual tree will remain in even-aged Norway spruce (Picea abies (L.) Karst.) stands subjected to different thinning programmes was modelled, using data from a thinning experiment established in 25 localities in southern Sweden. A logistic regression approach was used to predict the probability and the Hosmer–Lemeshow goodness-of-fit test to evaluate the fit. Diameter at breast height (DBH), quadratic mean DBH, thinning intensity, thinning quotient, basal area, number of stems per hectare, stand age, number of thinnings, and site index were used as explanatory variables. Separate analyses for stands thinned from below, stands thinned from above, and unthinned stands were performed. The modelled probability graphs for trees not being removed, plotted against their diameter at breast height, had clear S-shapes for both unthinned stands and stands thinned from below. The graph for stands thinned from above was bell-shaped.

scholarly journals A handheld device for measuring the diameter at breast height of individual trees using laser ranging and deep-learning based image recognition

Plant Methods ◽  
2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Chuangye Song ◽  
Bin Yang ◽  
Lin Zhang ◽  
Dongxiu Wu
Keyword(s):  
Measurement Accuracy ◽  
Focal Length ◽  
Digital Camera ◽  
Laser Ranging ◽  
Horizontal Distance ◽  
Tree Trunk ◽  
Handheld Device ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Individual Trees

Abstract Background Accurate and efficient measurement of the diameter at breast height (DBH) of individual trees is essential for forest inventories, ecological management, and carbon budget estimation. However, traditional diameter tapes are still the most widely used dendrometers in forest surveys, which makes DBH measurement time-consuming and labor-intensive. Automatic and easy-to-use devices for measuring DBH are highly anticipated in forest surveys. In this study, we present a handheld device for measuring the DBH of individual trees that uses digital cameras and laser ranging, allowing for an instant, automated, and contactless measurement of DBH. Results The base hardware of this device is a digital camera and a laser rangefinder, which are used to take a picture of the targeted tree trunk and record the horizontal distance between the digital camera and the targeted tree, respectively. The core software is composed of lightweight convolutional neural networks (CNNs), which includes an attention-focused mechanism for detecting the tree trunk to log the number of pixels between the edges. We also calibrated the digital camera to correct the distortion introduced by the lens system, and obtained the normalized focal length. Parameters including the horizontal distance between the digital camera and the targeted tree, number of pixels between the edges of the tree trunk, and normalized focal length were used to calculate the DBH based on the principles of geometrical optics. The measured diameter values, and the longitudes and latitudes of the measurement sites, were recorded in a text file, which is convenient to export to external flash disks. The field measurement accuracy test showed that the BIAS of the newly developed device was − 1.78 mm, and no significant differences were found between the measured diameter values and the true values (measured by the conventional tape). Furthermore, compared with most other image-based instruments, our device showed higher measurement accuracy. Conclusions The newly developed handheld device realized efficient, accurate, instant, and non-contact measurements of DBH, and the CNNs were proven to be successful in the detection of the tree trunk in our research. We believe that the newly developed device can fulfill the precision requirement in forest surveys, and that the application of this device can improve the efficiency of DBH measurements in forest surveys.

scholarly journals Relative effects of dendrometers on the estimation of diameter at breast height, stand basal area and stand volume in uneven-aged northern hardwoods

2009 ◽  
Vol 85 (3) ◽  
pp. 446-452 ◽  
Author(s):  
François Guillemette ◽  
Marie-Claude Lambert
Keyword(s):  
Basal Area ◽  
Major Axis ◽  
Minor Axis ◽  
Northern Hardwoods ◽  
Parameter Estimates ◽  
Betula Alleghaniensis ◽  
Stand Volume ◽  
Diameter At Breast Height ◽  
Breast Height ◽  
Stand Basal Area

Four methods of estimating diameter at breast height (DBH) were used on 558 northern hardwood stems, located in 6, 0.25-ha plots, to compare their effects. The first method was a diameter tape reading and the second was a systematic reading, along a predefined axis, taken with a calliper. The last 2 methods were both obtained from the arithmetic mean of 2 different pairs of calliper readings taken at right angles. The first pair was directed along the major bole axis and the other pair along the minor axis. The 4 methods were compared in terms of mean tree diameter, plot basal area and plot volume. There were significant differences (p < 0.05) in parameter estimates among methods, and the differences varied according to species (Acer saccharum Marsh. and Betula alleghaniensis Britt.) and tree size class. Differences among methods were more evident for larger DBH classes, which contribute most to the significant differences observed for both the plot and stand basal area and volume. Overall, tree DBH, plot basal area and plot volume provided by these 4 methods ranked in this ascending order: mean calliper reading directed along the minor axis, systematic calliper reading, mean calliper reading directed along the major axis, and diameter tape. The difference in stand basal area or volume between the estimates obtained with a systematic calliper reading and a diameter tape was 1.1 m2/ha with a mean basal area of about 21 m2/ha, or 10.5 m3/ha with a mean stand volume of 169 m3/ha. Because of the magnitude of these differences, it is recommended the method of DBH estimation be specified in studies, to be careful when crossing databases or models using different methods of DBH estimation, and to always maintain the same method of DBH estimation when remeasuring a plot. Key words: northern hardwoods, dendrometer, diameter tape, calliper, caliper, DBH measurement, basal area, volume

Sign in / Sign up

Export Citation Format

Share Document