ESTIMATION OF ABOVE GROUND FOREST BIOMASS USING ULTRA HIGH RESOLUTION UAV IMAGES: A CASE STUDY FROM BARANDABHAR FOREST, NEPAL

Abstract. Forest biomass is the sum of above ground living organic material contained in trees which is expressed as dry weight per unit area. Forest biomass acts as substantial terrestrial carbon sinks, they are estimated to absorb 2.7 Petagrams of carbon per year, as such accurate estimation of forest carbon stock is very important. The estimation of biomass is also important because of its application in commercial exploitation as well as in global carbon cycle. Particularly in the latter context, the estimation of the total above-ground biomass (TAGB) with sufficient accuracy is vital in reporting the spatial and temporal state of forest under the United Nations Framework Convention on Climate Change (UNFCCC), Reducing Emissions from Deforestation in Developing Countries (REDD). In this research, tree height, DBH and crown cover were measured using field instruments. Individual ultra-high-resolution UAV images acquired using customized Visible-NIR, were georeferenced and tree crown were extracted using multi-resolution segmentation. A regression equation between field measured biomass and Crown Projection Area (CPA) was developed. The paper presents results from Barandabhar Forest of Chitwan District, Nepal. RMSE of ortho-mosaic was found to be 18 cm. While R2 value of 89% was obtained for relationship between DBH and biomass, that of 61% was attained for relationship between CPA and biomass.

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A protocol for sampling vascular epiphyte richness and abundance

Journal of Tropical Ecology ◽

10.1017/s0266467408005786 ◽

2009 ◽

Vol 25 (2) ◽

pp. 107-121 ◽

Cited By ~ 24

Author(s):

Jan H. D. Wolf ◽

S. Robbert Gradstein ◽

Nalini M. Nadkarni

Keyword(s):

Tree Height ◽

Dry Weight ◽

Mantel Test ◽

Tree Size ◽

Tree Level ◽

Trunk Diameter ◽

Host Trees ◽

Epiphyte Communities ◽

Vascular Epiphyte

Abstract:The sampling of epiphytes is fraught with methodological difficulties. We present a protocol to sample and analyse vascular epiphyte richness and abundance in forests of different structure (SVERA). Epiphyte abundance is estimated as biomass by recording the number of plant components in a range of size cohorts. Epiphyte species biomass is estimated on 35 sample-trees, evenly distributed over six trunk diameter-size cohorts (10 trees with dbh > 30 cm). Tree height, dbh and number of forks (diameter > 5 cm) yield a dimensionless estimate of the size of the tree. Epiphyte dry weight and species richness between forests is compared with ANCOVA that controls for tree size. SChao1 is used as an estimate of the total number of species at the sites. The relative dependence of the distribution of the epiphyte communities on environmental and spatial variables may be assessed using multivariate analysis and Mantel test. In a case study, we compared epiphyte vegetation of six Mexican oak forests and one Colombian oak forest at similar elevation. We found a strongly significant positive correlation between tree size and epiphyte richness or biomass at all sites. In forests with a higher diversity of host trees, more trees must be sampled. Epiphyte biomass at the Colombian site was lower than in any of the Mexican sites; without correction for tree size no significant differences in terms of epiphyte biomass could be detected. The occurrence of spatial dependence, at both the landscape level and at the tree level, shows that the inclusion of spatial descriptors in SVERA is justified.

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TRIPLOID APPLE VARIETIES OF SUMMER RIPENING SELECTION VNIISPK ON CLONAL ROOTSTOCK 54-118

Vestnik of the Russian agricultural science ◽

10.30850/vrsn/2021/6/34-36 ◽

1970 ◽

pp. 34-36

Author(s):

А. M. Galasheva ◽

Е. N. Sedov

Keyword(s):

Tree Height ◽

Projection Area ◽

Cross Sectional ◽

Crown Width ◽

Crown Volume ◽

The World ◽

Apple Cultivars ◽

Crown Projection Area ◽

Academy Of Sciences ◽

First Time

For the first time in the world and in Russia, Academician of the Russian Academy of Sciences, breeder Evgeny Nikolaevich Sedov created a series of triploid apple cultivars from intervalent crosses 2х × 4х. Triploid apple cultivars bear fruit more regularly, have higher self-fruitfulness and have fruits of high marketability. The article presents data on the study of triploid apple cultivars of the summer ripening period of the VNIISPK breeding - Augusta, Daryona, Maslovskoye, Osipovskoye, Zhilinskoye, Spasskoye and Yablochny Spas as well as the control Canadian cultivar Melba on a semi-dwarf clone rootstock 54-118. Maslovskoye, Zhilinskoye, Spasskoye and Yablochny Spas have immunity to scab. The orchard was planted in 2014, the garden planting scheme was 5 x 2 m. The indicators of the growth force (tree height, crown width and stem diameter) and the yield of trees were studied. At the age of six, the trees of triploid cultivars reached a height of 2.2 m (Maslovskoye) to 3.0 m (Yablochny Spas) on a semi-dwarf rootstock 54-118. The highest indicators of crown volume (3.3-5.3 m3), crown projection area (4.2-5.3 m2) and the cross-sectional area of the stem (46.5-52.8 cm2) were in Osipovskoye, Yablochny Spas, Zhilinskoye and Spasskoye. The highest yield in an average of three years was given by triploid scab-immune apple cultivars on a semi-dwarf rootstock 54-118: Maslovskoye, Zhilinskoye, Spasskoye and Yablochny Spas.

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Estimation of Tree Height and Forest Biomass Using Airborne LiDAR Data: A Case Study of Londiani Forest Block in the Mau Complex, Kenya

Open Journal of Forestry ◽

10.4236/ojf.2017.72016 ◽

2017 ◽

Vol 07 (02) ◽

pp. 255-269 ◽

Cited By ~ 5

Author(s):

Faith Kagwiria Mutwiri ◽

Patroba Achola Odera ◽

Mwangi James Kinyanjui

Keyword(s):

Forest Biomass ◽

Tree Height ◽

Airborne Lidar ◽

Lidar Data ◽

Airborne Lidar Data

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Tree crown size as a measure of tree biosocial position in 135-year-old oak (Quercus L.) stand

Folia Forestalia Polonica ◽

10.1515/ffp-2016-0004 ◽

2016 ◽

Vol 58 (1) ◽

pp. 31-42 ◽

Cited By ~ 1

Author(s):

Katarzyna Kaźmierczak ◽

Bogna Zawieja

Keyword(s):

Principal Component ◽

Tree Height ◽

Projection Area ◽

Tree Crown ◽

Diameter At Breast Height ◽

Breast Height ◽

Crown Length ◽

Pca Method ◽

Crown Projection Area

AbstractThe paper presents an attempt to apply measurable traits of a tree – crown projection area, crown length, diameter at breast height and tree height for classification of 135-year-old oak (QuercusL.) trees into Kraft classes. Statistical multivariate analysis was applied to reach the aim. Empirical material was collected on sample plot area of 0.75 ha, located in 135-year-old oak stand. Analysis of dimensional traits of oaks from 135-year-old stand allows quite certain classification of trees into three groups: pre-dominant, dominant and co-dominant and dominated ones. This seems to be quite promising, providing a tool for the approximation of the biosocial position of tree with no need for assessment in forest. Applied analyses do not allow distinguishing trees belonging to II and III Kraft classes. Unless the eye-estimation-based classification is completed, principal component analysis (PCA) method provided simple, provisional solution for grouping trees from 135-year-old stand into three over-mentioned groups. Discriminant analysis gives more precise results compared with PCA. In the analysed stand, the most important traits for the evaluation of biosocial position were diameter at breast height, crown projection area and height.

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Crown efficiency in a loblolly pine (Pinus taeda) spacing experiment

Canadian Journal of Forest Research ◽

10.1139/x98-115 ◽

1998 ◽

Vol 28 (9) ◽

pp. 1344-1351 ◽

Cited By ~ 12

Author(s):

Hubert Sterba ◽

Ralph L Amateis

Keyword(s):

Pinus Taeda ◽

Loblolly Pine ◽

Basal Area ◽

Tree Height ◽

Projection Area ◽

Individual Tree ◽

Dominant Height ◽

Crown Projection Area ◽

Pinus Taeda L ◽

Crown Closure

Crown efficiency was first defined by Assmann (1961. Waldertragskunde. BLV, München) as individual tree volume increment per unit of crown projection area. He hypothesized that within a given crown class, smaller crowns are more efficient because their ratio between crown surface and horizontal crown projection is higher. Data from a loblolly pine (Pinus taeda L.) spacing experiment were used to test if this hypothesis also holds in young loblolly pine stands and, if so, to determine if it explains the increment differences between spacings in the spacing experiment. Using individual tree height relative to plot dominant height to describe crown class, within-plot regression showed that crown efficiency decreased with crown size for trees below dominant height. This relationship was much less pronounced than indicated from Assmann's examples, although the crown surface to crown projection ratio behaved in the same way as Assmann had hypothesized. Crown efficiency as well as the crown surface to crown projection area ratio decreased with increasing density. Basal area increment per hectare increased until total crown closure approached 130% and then stayed constant. This major impact of total crown coverage brings into question the usefullness of crown efficiency as an indicator for unit area growth.

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Carbon Status and Regression Model for Tree Carbon by Crown Cover for Sal Forest of Nepal

10.21203/rs.2.19432/v1 ◽

2019 ◽

Author(s):

Prashant Paudel ◽

Rupesh Kalakheti ◽

Tek Maraseni

Keyword(s):

Regression Model ◽

Carbon Stock ◽

Tree Height ◽

Categorical Variables ◽

Accurate Estimation ◽

Natural Logarithm ◽

Crown Cover ◽

Forest Condition ◽

Significant Difference ◽

Cover Class

Abstract Volume, biomass and carbon of forest ecosystem are generally estimated using lookup tables or allometric equations known as models. These general equation-based models are usually exclusively based on dimensional measurement such as diameter at breast height (DBH) and/or height, which sometimes makes it difficult to judge applicability of equation to given forest condition or types. It is therefore important to estimate carbon stock and develop models to predict biomass or carbon stock with stratification by categorical variables like crown cover, slope, forest types, etc. Stratification of forest by remote sensing approach while designing forest inventory not only improves the reliability of the estimation but also reduces the cost of measurement. Taking crown coverage (<25%, 25-50%, 50-75% and >75%) as a categorical variable, this study assessed the status of carbon stock and develop a regression model to predict carbon stock for each canopy class of Sal (Shorea robusta) forest in Nepal. DBH and height were measured for trees with more than 7 cm DBH in 82 sample plots (18, 22, 22 and 20 for <25%, 25-50%, 50-75% and >75% respectively). On average 297 stands per hectare were recorded with 94.80 m 3 /ha growing stock. Carbon stock was highest for >75% crown cover class (89.83 ton C/ha) and lowest for <25% crown cover class (27.47 ton C/ha) with average 60.41 ton C/ha, where per tree carbon stock was lowest in crown cover class 25-50% (0.16 ton C/tree). TukeyHSD shows that four pairs of crown cover classes have significant difference in carbon stock at 95% confidence interval. Regression model with natural logarithm of DBH 2 and total tree height was best fitted for estimation of carbon stock per tree in different crown cover class with adjusted R 2 >0.99 and residuals were normally distributed. Adjustment of model (natural logarithm of DBH 2 and height) with high accuracy (R 2 >0.99) shows the importance of stratification especially by crown cover for accurate estimation of carbon stock for optimization of carbon benefits.

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Optimizing spaceborne LiDAR and very high resolution optical sensor parameters for biomass estimation at ICESat/GLAS footprint level using regression algorithms

Progress in Physical Geography Earth and Environment ◽

10.1177/0309133317693443 ◽

2017 ◽

Vol 41 (3) ◽

pp. 247-267 ◽

Cited By ~ 14

Author(s):

P Dhanda ◽

S Nandy ◽

SPS Kushwaha ◽

S Ghosh ◽

YVN Krishna Murthy ◽

...

Keyword(s):

High Resolution ◽

Forest Biomass ◽

Optical Data ◽

Accurate Estimation ◽

Support Vector ◽

Biomass Estimation ◽

Multiple Sensors ◽

Forest Height ◽

Regression Algorithms ◽

Single Sensor

Forests sequester large quantity of carbon in their woody biomass and hence accurate estimation of forest biomass is extremely crucial. The present study aims at combining information from spaceborne LiDAR (ICESat/GLAS) and high resolution optical data to estimate forest biomass. Estimation of aboveground biomass (AGB) at ICESat/GLAS footprint level was done by integrating data from multiple sensors using two regression algorithms, viz. random forest (RF) and support vector machine (SVM). The study used forest height and canopy return ratio (rCanopy) for determination of effective size of ICESat/GLAS footprints for field data collection. The forest height was predicted with root mean square error (RMSE) of 1.35 m. The study showed that six most important parameters derived from LiDAR, and passive optical data were able to explain 78.7% (adjusted) variation in the observed AGB with an RMSE of 13.9 Mg ha–1. It was also observed that 15 most important parameters were able to explain 83% (adjusted) variation in the observed AGB. It was found that SVM regression algorithm explained 88.7% of variation in AGB with an RMSE of 13.6 Mg ha–1 on the combined datasets while RF regression algorithm explained 83.5% of variation in AGB with an RMSE of 20.57 Mg ha–1. The study demonstrated that RF regression algorithm performs equally well on datasets irrespective of the correlation of underlying variables with the predicted variable whereas SVM regression was found to perform well on those datasets which had a subset of underlying variables that are correlated with the predicted variable. The study highlighted that sensor integration approach is more accurate than single sensor approach in predicting the AGB.

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Slenderness of pedunculate oak (Quercus robur L.) according to biosocial position

Agronomy Science ◽

10.24326/asx.2018.3.4 ◽

2018 ◽

Vol 73 (3) ◽

pp. 37-43

Author(s):

ZDZISŁAW KACZMARSKI ◽

KATARZYNA MASTERNAK ◽

MATEUSZ JARMUŁ

Keyword(s):

Basal Area ◽

Tree Height ◽

Projection Area ◽

Pedunculate Oak ◽

Single Tree ◽

Crown Length ◽

Crown Width ◽

Growth Space ◽

Oak Tree ◽

Crown Projection Area

The paper presents results of an analysis of pedunculate oak slenderness. The dependence between slenderness of the oak tree and dimensions of the trunk and the crown dimensions of a single tree were examined. The biosocial position of each tree was determined based on the Kraft’s classification criteria. Following dimensions were measured for each tree: height, height of base of live crown, crown radius, diameter at breast height. The following crown parameters related to the growth space of a single tree were determined: crown length, crown width, crown projection area, space of a single tree, Seebach’s growth space number, crown projection area to basal area ratio, crown spread. Based on the obtained results, the following was found: biosocial position of the oak tree in vertical structure of the stand has significant impact on the size of the tree slenderness; the slenderness increases with deterioration of the biosocial position of the tree, but it decreases with the increase in the value of the tree’s measurement characteristics and the measures of its crown.

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Height-diameter allometry for tropical forest in northern Amazonia

10.1101/2021.08.04.455098 ◽

2021 ◽

Author(s):

Robson Borges de Lima ◽

Eric Bastos Görgens ◽

Fernando Elias ◽

Jadson Coelho de Abreu ◽

Aldine Luiza Baia ◽

...

Keyword(s):

New Technologies ◽

Environmental Variability ◽

Forest Biomass ◽

Tree Height ◽

Weibull Model ◽

Accurate Estimation ◽

Individual Tree ◽

Allometric Models ◽

True Tree ◽

Tree Height Growth

Height measurements are essential to manage and monitor forest biomass and carbon stocks. However, accurate estimation of this variable in tropical ecosystems is still difficult due to species heterogeneity and environmental variability. In this article, we compare and discuss six nonlinear allometric models parameterized at different scales (local, regional and pantropical). We also evaluate the height measurements obtained in the field by the hypsometer when compared with the true tree height. We used a dataset composed of 180 harvested trees in two distinct areas located in the Amapá State. The functional form of the Weibull model was the best local model, showing similar performance to the pantropical model. The inaccuracy detected in the hypsometer estimates reinforces the importance of incorporating new technologies in measuring individual tree heights. Establishing accurate allometric models requires knowledge of ecophysiological and environmental processes that govern vegetation dynamics and tree height growth. It is essential to investigate the influence of different species and ecological gradients on the diameter/height ratio.

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