Tree height integrated into pan-tropical forest biomass estimates

Abstract. Above-ground tropical tree biomass and carbon storage estimates commonly ignore tree height. We estimate the effect of incorporating height (H) on forest biomass estimates using 37 625 concomitant H and diameter measurements (n = 327 plots) and 1816 harvested trees (n = 21 plots) tropics-wide to answer the following questions: 1. For trees of known biomass (from destructive harvests) which H-model form and geographic scale (plot, region, and continent) most reduces biomass estimate uncertainty? 2. How much does including H relationship estimates derived in (1) reduce uncertainty in biomass estimates across 327 plots spanning four continents? 3. What effect does the inclusion of H in biomass estimates have on plot- and continental-scale forest biomass estimates? The mean relative error in biomass estimates of the destructively harvested trees was half (mean 0.06) when including H, compared to excluding H (mean 0.13). The power- and Weibull-H asymptotic model provided the greatest reduction in uncertainty, with the regional Weibull-H model preferred because it reduces uncertainty in smaller-diameter classes that contain the bulk of biomass per hectare in most forests. Propagating the relationships from destructively harvested tree biomass to each of the 327 plots from across the tropics shows errors are reduced from 41.8 Mg ha−1 (range 6.6 to 112.4) to 8.0 Mg ha−1 (−2.5 to 23.0) when including $H$. For all plots, above-ground live biomass was 52.2±17.3 Mg ha−1 lower when including H estimates (13%), with the greatest reductions in estimated biomass in Brazilian Shield forests and relatively no change in the Guyana Shield, central Africa and southeast Asia. We show fundamentally different stand structure across the four forested tropical continents, which affects biomass reductions due to $H$. African forests store a greater portion of total biomass in large-diameter trees and trees are on average larger in diameter. This contrasts to forests on all other continents where smaller-diameter trees contain the greatest fractions of total biomass. After accounting for variation in $H$, total biomass per hectare is greatest in Australia, the Guyana Shield, and Asia and lowest in W. Africa, W. Amazonia, and the Brazilian Shield (descending order). Thus, if closed canopy tropical forests span 1668 million km2 and store 285 Pg C, then the overestimate is 35 Pg C if H is ignored, and the sampled plots are an unbiased statistical representation of all tropical forest in terms of biomass and height factors. Our results show that tree $H$ is an important allometric factor that needs to be included in future forest biomass estimates to reduce error in estimates of pantropical carbon stocks and emissions due to deforestation.

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Tree height integrated into pantropical forest biomass estimates

Biogeosciences ◽

10.5194/bg-9-3381-2012 ◽

2012 ◽

Vol 9 (8) ◽

pp. 3381-3403 ◽

Cited By ~ 239

Author(s):

T. R. Feldpausch ◽

J. Lloyd ◽

S. L. Lewis ◽

R. J. W. Brienen ◽

M. Gloor ◽

...

Keyword(s):

East Africa ◽

Carbon Storage ◽

Stand Structure ◽

Forest Biomass ◽

Small Diameter ◽

Tree Height ◽

Total Biomass ◽

Guiana Shield ◽

Tree Biomass ◽

Continental Scale

Abstract. Aboveground tropical tree biomass and carbon storage estimates commonly ignore tree height (H). We estimate the effect of incorporating H on tropics-wide forest biomass estimates in 327 plots across four continents using 42 656 H and diameter measurements and harvested trees from 20 sites to answer the following questions: 1. What is the best H-model form and geographic unit to include in biomass models to minimise site-level uncertainty in estimates of destructive biomass? 2. To what extent does including H estimates derived in (1) reduce uncertainty in biomass estimates across all 327 plots? 3. What effect does accounting for H have on plot- and continental-scale forest biomass estimates? The mean relative error in biomass estimates of destructively harvested trees when including H (mean 0.06), was half that when excluding H (mean 0.13). Power- and Weibull-H models provided the greatest reduction in uncertainty, with regional Weibull-H models preferred because they reduce uncertainty in smaller-diameter classes (≤40 cm D) that store about one-third of biomass per hectare in most forests. Propagating the relationships from destructively harvested tree biomass to each of the 327 plots from across the tropics shows that including H reduces errors from 41.8 Mg ha−1 (range 6.6 to 112.4) to 8.0 Mg ha−1 (−2.5 to 23.0). For all plots, aboveground live biomass was −52.2 Mg ha−1 (−82.0 to −20.3 bootstrapped 95% CI), or 13%, lower when including H estimates, with the greatest relative reductions in estimated biomass in forests of the Brazilian Shield, east Africa, and Australia, and relatively little change in the Guiana Shield, central Africa and southeast Asia. Appreciably different stand structure was observed among regions across the tropical continents, with some storing significantly more biomass in small diameter stems, which affects selection of the best height models to reduce uncertainty and biomass reductions due to H. After accounting for variation in H, total biomass per hectare is greatest in Australia, the Guiana Shield, Asia, central and east Africa, and lowest in east-central Amazonia, W. Africa, W. Amazonia, and the Brazilian Shield (descending order). Thus, if tropical forests span 1668 million km2 and store 285 Pg C (estimate including H), then applying our regional relationships implies that carbon storage is overestimated by 35 Pg C (31–39 bootstrapped 95% CI) if H is ignored, assuming that the sampled plots are an unbiased statistical representation of all tropical forest in terms of biomass and height factors. Our results show that tree H is an important allometric factor that needs to be included in future forest biomass estimates to reduce error in estimates of tropical carbon stocks and emissions due to deforestation.

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Stand structure links up canopy processes and forest management

Forestry Studies / Metsanduslikud Uurimused ◽

10.2478/v10132-011-0076-8 ◽

2009 ◽

Vol 51 (1) ◽

pp. 40-48

Author(s):

Toomas Frey

Keyword(s):

Forest Management ◽

Stand Structure ◽

Net Primary Production ◽

Stand Density ◽

Tree Height ◽

Belowground Biomass ◽

Unit Mass ◽

Total Biomass ◽

Individual Tree ◽

Mean Values

Stand structure links up canopy processes and forest management Above- and belowground biomass and net primary production (Pn) of a maturing Norway spruce (Picea abies (L.) Karst.) forest (80 years old) established on brown soil in central Estonia were 227, 50 and 19.3 Mg ha correspondingly. Stand structure is determined mostly by mean height and stand density, used widely in forestry, but both are difficult to measure with high precision in respect of canopy processes in individual trees. However, trunk form quotient (q2) and proportion of living crown in relation to tree height are useful parameters allowing describe stand structure tree by tree. Based on 7 model trees, leaf unit mass assimilation activity and total biomass respiration per unit mass were determined graphically as mean values for the whole tree growth during 80 years of age. There are still several possible approaches not used carefully enough to integrate experimental work at instrumented towers with actual forestry measurement. Dependence of physiological characteristics on individual tree parameters is the missing link between canopy processes and forest management.

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Hiperdominansi Jenis dan Biomassa Pohon di Taman Nasional Gunung Gede Pangrango, Indonesia

Jurnal Ilmu Kehutanan ◽

10.22146/jik.24903 ◽

2017 ◽

Vol 11 (1) ◽

pp. 85

Author(s):

Andes Hamuraby Rozak ◽

Sri Astutik ◽

Zaenal Mutaqien ◽

Didik Widyatmoko ◽

Endah Sulistyawati

Keyword(s):

Tree Species ◽

National Park ◽

Forest Biomass ◽

Forest Monitoring ◽

Mountain Forest ◽

Total Biomass ◽

Tree Biomass ◽

Large Trees ◽

Average Biomass ◽

Schima Wallichii

Hiperdominansi jenis dan biomassa adalah suatu konsep yang menjelaskan pentingnya sebagian kecil jenis dan biomassa relatif terhadap rata-rata biomassa pohon pada suatu kawasan hutan. Pemahaman pada konsep ini berimplikasi pada upaya monitoring kawasan hutan khususnya bagi spesies penyumbang biomassa terbesar dan membantu pemahaman pada proses restorasi ekologinya. Analisis hiperdominansi jenis dan kontribusi pohon besar (DBH>50 cm) terhadap biomassa pohon telah dilakukan di kawasan hutan Taman Nasional Gunung Gede Pangrango (TNGGP). Sejumlah 26 plot pengamatan telah dibuat pada 26 level ketinggian yang berbeda (1013-3010 m dpl) dan dikelompokkan menjadi tiga zona yaitu zona submontana, montana, dan subalpine. Pohon-pohon yang terdapat dalam plot pengamatan kemudian dikelompokkan menjadi 3 kelompok diameter yaitu pohon kecil (5-30 cm), pohon sedang (30-50 cm), dan pohon besar (>50 cm). Hasil analisis menunjukkan bahwa hiperdominansi jenis terjadi di hutan TNGGP. Empat jenis pohon dari 114 jenis yang teridentifikasi yaitu Schima wallichii, Altingia excelsa, Vaccinium varingiaefolium, dan Castanopsis acuminatissima merepresentasikan 56,96% dari total biomassa pohon yang ada di plot TNGGP. Lebih lanjut, pohon kecil dan besar diketahui sebagai penyumbang biomassa yang sangat signifikan dibandingkan pohon sedang. Pada level plot penelitian, pohon dengan DBH>50 cm yang berjumlah 192 individu (atau 13%) dari 1471 individu pohon mampu merepresentasikan 61,4% dari total biomassanya. Namun demikian, pada level kawasan hutan, pohon kecil dan pohon besar memiliki kontribusi yang sama signifikannya terhadap biomassa per hektarnya yaitu masing-masing sebesar 40,9% dan 38,77%. Hasil-hasil tersebut menunjukkan bahwa hanya sedikit jenis pohon saja mampu merepresentasikan sebagian besar dari total biomassa pohon. Pohon-pohon kecil dan besar diketahui memainkan peranan yang penting dalam biomassa di hutan TNGGP.Hyperdominance of Tree Species and Biomass in Mount Gede Pangrango National Park, IndonesiaAbstractThe hyperdominance of tree species and biomass is a concept explaining the importance of a small portion of species and biomass relative to the average of biomass in a forested area. Understanding this concept has important implication on forest monitoring, especially to monitor the most significant species that show high contributes on biomass and its ecological restoration. Hyperdominance analysis of tree species and large trees (DBH > 50 cm) contribution to tree biomass were investigated in tropical mountain forest of Mount Gede Pangrango National Park (TNGGP). A total of 26 sample plots were installed in 26 different altitude between 1013 and 3010 m asl and grouped into three zones i.e. submontane, montane, and subalpine zones. Trees within plot were identified, measured, and grouped into three groups i.e. small (DBH 5-30 cm), medium (DBH 30-50 cm), and large trees (DBH>50 cm). The result showed that there were hyperdominant in TNGGP. Four species from 114 identified tree species i.e. Schima wallichii, Altingia excelsa, Vaccinium varingiaefolium, and Castanopsis acuminatissima represented 56.96% of the total biomass in the plot level. Furthermore, only 13% of trees from 1471 trees responsible for 61.4% of the total tree biomass in the plot level. However, small and large trees have similar significant contribution to the average biomass in the forest level i.e. 40.9% and 38.77%, respectively. These results suggest that only few species represent a huge amount of biomass. Both small and large trees play important role in the forest biomass of TNGGP.

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Height-diameter allometry of tropical forest trees

Biogeosciences ◽

10.5194/bg-8-1081-2011 ◽

2011 ◽

Vol 8 (5) ◽

pp. 1081-1106 ◽

Cited By ~ 267

Author(s):

T. R. Feldpausch ◽

L. Banin ◽

O. L. Phillips ◽

T. R. Baker ◽

S. L. Lewis ◽

...

Keyword(s):

Tropical Forest ◽

Large Scale ◽

Amazon Basin ◽

Stand Structure ◽

Forest Type ◽

Structural Characteristics ◽

Basal Area ◽

Tree Height ◽

Geographic Region ◽

True Value

Abstract. Tropical tree height-diameter (H:D) relationships may vary by forest type and region making large-scale estimates of above-ground biomass subject to bias if they ignore these differences in stem allometry. We have therefore developed a new global tropical forest database consisting of 39 955 concurrent H and D measurements encompassing 283 sites in 22 tropical countries. Utilising this database, our objectives were: 1. to determine if H:D relationships differ by geographic region and forest type (wet to dry forests, including zones of tension where forest and savanna overlap). 2. to ascertain if the H:D relationship is modulated by climate and/or forest structural characteristics (e.g. stand-level basal area, A). 3. to develop H:D allometric equations and evaluate biases to reduce error in future local-to-global estimates of tropical forest biomass. Annual precipitation coefficient of variation (PV), dry season length (SD), and mean annual air temperature (TA) emerged as key drivers of variation in H:D relationships at the pantropical and region scales. Vegetation structure also played a role with trees in forests of a high A being, on average, taller at any given D. After the effects of environment and forest structure are taken into account, two main regional groups can be identified. Forests in Asia, Africa and the Guyana Shield all have, on average, similar H:D relationships, but with trees in the forests of much of the Amazon Basin and tropical Australia typically being shorter at any given D than their counterparts elsewhere. The region-environment-structure model with the lowest Akaike's information criterion and lowest deviation estimated stand-level H across all plots to within amedian −2.7 to 0.9% of the true value. Some of the plot-to-plot variability in H:D relationships not accounted for by this model could be attributed to variations in soil physical conditions. Other things being equal, trees tend to be more slender in the absence of soil physical constraints, especially at smaller D. Pantropical and continental-level models provided less robust estimates of H, especially when the roles of climate and stand structure in modulating H:D allometry were not simultaneously taken into account.

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Field methods for sampling tree height for tropical forest biomass estimation

Methods in Ecology and Evolution ◽

10.1111/2041-210x.12962 ◽

2018 ◽

Vol 9 (5) ◽

pp. 1179-1189 ◽

Cited By ~ 37

Author(s):

Martin J. P. Sullivan ◽

Simon L. Lewis ◽

Wannes Hubau ◽

Lan Qie ◽

Timothy R. Baker ◽

...

Keyword(s):

Tropical Forest ◽

Forest Biomass ◽

Tree Height ◽

Biomass Estimation ◽

Field Methods

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Height-diameter allometry of tropical forest trees

Biogeosciences Discussions ◽

10.5194/bgd-7-7727-2010 ◽

2010 ◽

Vol 7 (5) ◽

pp. 7727-7793 ◽

Cited By ~ 30

Author(s):

T. R. Feldpausch ◽

L. Banin ◽

O. L. Phillips ◽

T. R. Baker ◽

S. L. Lewis ◽

...

Keyword(s):

Tropical Forest ◽

Large Scale ◽

Amazon Basin ◽

Stand Structure ◽

Forest Type ◽

Structural Characteristics ◽

Basal Area ◽

Tree Height ◽

Geographic Region ◽

True Value

Abstract. Tropical tree height-diameter (H:D) relationships may vary by forest type and region making large-scale estimates of above-ground biomass subject to bias if they ignore these differences in stem allometry. We have therefore developed a new global tropical forest database consisting of 39 955 concurrent H and D measurements encompassing 283 sites in 22 tropical countries. Utilising this database, our objectives were: 1. to determine if H:D relationships differ by geographic region and forest type (wet to dry forests, including zones of tension where forest and savanna overlap). 2. to ascertain if the H:D relationship is modulated by climate and/or forest structural characteristics (e.g. stand-level basal area, A). 3. to develop H:D allometric equations and evaluate biases to reduce error in future local-to-global estimates of tropical forest biomass. Annual precipitation coefficient of variation (PV), dry season length (SD), and mean annual air temperature (TA) emerged as key drivers of variation in H:D relationships at the pantropical and region scales. Vegetation structure also played a role with trees in forests of a high A being, on average, taller at any given D. After the effects of environment and forest structure are taken into account, two main regional groups can be identified. Forests in Asia, Africa and the Guyana Shield all have, on average, similar H:D relationships, but with trees in the forests of much of the Amazon Basin and tropical Australia typically being shorter at any given D than their counterparts elsewhere. The region-environment-structure model with the lowest Akaike's information criterion and lowest deviation estimated stand-level H across all plots to within a median –2.7 to 0.9% of the true value. Some of the plot-to-plot variability in H:D relationships not accounted for by this model could be attributed to variations in soil physical conditions. Other things being equal, trees tend to be more slender in the absence of soil physical constraints, especially at smaller D. Pantropical and continental-level models provided only poor estimates of H, especially when the roles of climate and stand structure in modulating H:D allometry were not simultaneously taken into account.

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Restore and sequester: estimating biomass in native Australian woodland ecosystems for their carbon-funded restoration

Australian Journal of Botany ◽

10.1071/bt11018 ◽

2011 ◽

Vol 59 (7) ◽

pp. 640 ◽

Cited By ~ 18

Author(s):

J. H. Jonson ◽

D. Freudenberger

Keyword(s):

Native Species ◽

Basal Area ◽

Tree Height ◽

Ground Level ◽

Stem Diameter ◽

Allometric Equations ◽

Total Biomass ◽

Tree Biomass ◽

Below Ground ◽

Total Tree

In the south-western region of Australia, allometric relationships between tree dimensional measurements and total tree biomass were developed for estimating carbon sequestered in native eucalypt woodlands. A total of 71 trees representing eight local native species from three genera were destructively sampled. Within this sample set, below ground measurements were included for 51 trees, enabling the development of allometric equations for total biomass applicable to small, medium, and large native trees. A diversity of tree dimensions were recorded and regressed against biomass, including stem diameter at 130 cm (DBH), stem diameter at ground level, stem diameter at 10 cm, stem diameter at 30 cm, total tree height, height of canopy break and mean canopy diameter. DBH was consistently highly correlated with above ground, below ground and total biomass. However, measurements of stem diameters at 0, 10 and 30 cm, and mean canopy diameter often displayed equivalent and at times greater correlation with tree biomass. Multi-species allometric equations were also developed, including ‘Mallee growth form’ and ‘all-eucalypt’ regressions. These equations were then applied to field inventory data collected from three locally dominant woodland types and eucalypt dominated environmental plantings to create robust relationships between biomass and stand basal area. This study contributes the predictive equations required to accurately quantify the carbon sequestered in native woodland ecosystems in the low rainfall region of south-western Australia.

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Assessment of temporal changes in aboveground forest tree biomass using aerial photographs and allometric equations

Canadian Journal of Forest Research ◽

10.1139/x06-152 ◽

2006 ◽

Vol 36 (10) ◽

pp. 2585-2594 ◽

Cited By ~ 20

Author(s):

Avi Bar Massada ◽

Yohay Carmel ◽

Gilad Even Tzur ◽

José M Grünzweig ◽

Dan Yakir

Keyword(s):

Pinus Halepensis ◽

Forest Biomass ◽

Tree Height ◽

Field Measurements ◽

Forest Tree ◽

Allometric Equation ◽

Aerial Photographs ◽

Tree Biomass ◽

Crown Diameter ◽

Biomass Dynamics

Studies of forest biomass dynamics typically use long-term forest inventory data, available in only a few places around the world. We present a method that uses photogrammetric measurements from aerial photographs as an alternative to time-series field measurements. We used photogrammetric methods to measure tree height and crown diameter, using four aerial photographs of Yatir Forest, a semi-arid forest in southern Israel, taken between 1978 and 2003. Height and crown-diameter measurements were transformed to biomass using an allometric equation generated from 28 harvested Aleppo pine (Pinus halepensis Mill.) trees. Mean tree biomass increased from 6.37 kg in 1978 to 97.01 kg in 2003. Mean plot biomass in 2003 was 2.48 kg/m2 and aboveground primary productivity over the study period ranged between 0.14 and 0.21 kg/m2 per year. There was systematic overestimation of tree height and systematic underestimation of crown diameter, which was corrected for at all time points between 1978 and 2003. The estimated biomass was significantly related to field-measured biomass, with an R2 value of 0.78. This method may serve as an alternative to field sampling for studies of forest biomass dynamics, assuming that there is sufficient spatial and temporal coverage of the investigated area using high-quality aerial photography, and that the tree tops are distinguishable in the photographs.

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Multiple Drivers of Biomass Change in Subtropical Natural Forests

10.21203/rs.3.rs-625148/v1 ◽

2021 ◽

Author(s):

Anchi Wu ◽

Xuli Tang ◽

Andi Li ◽

Xin Xiong ◽

Juxiu Liu ◽

...

Keyword(s):

Functional Traits ◽

Stand Structure ◽

Large Diameter ◽

Forest Biomass ◽

Ecosystem Functions ◽

Management Approach ◽

Maximum Height ◽

Natural Forests ◽

Niche Complementarity ◽

Positive Effect

Abstract Forest ecosystems play an important role in regulating the global carbon, a substantial portion of terrestrial carbon pool which is stored in biomass stocks. However, how multiple biotic (i.e. topography) and abiotic (biodiversity, stand structure, and functional traits) influence forest biomass in natural forests, the relative important of these factors determine biomass is still controversial for subtropical natural forests. We used forest inventory data from nine 1-ha plots at different altitude gradients in China’s subtropical forests. We used multiple analyse to quantify the relative importance of multiple facets of diversity, key functional traits, stand structural attributes, and topography variables in determining forest biomass. We found that multiple facets of diversity and stand structure variables enhances biomass. Specifically, large-diameter trees had a strong positive effect on biomass and were the most important factor in determining biomass. Plant functional traits were closely related to biomass. Community-weighted mean value (CWM) of maximum height positively correlated with biomass, but CWM of wood density negatively correlated biomass. Topographic factors including elevation and slope, had a positive effect on biomass. Moreover, among the aforementioned four types of variables, stand structure had the greatest impact on biomass and is linked to diversity-biomass relationship. Topography mainly indirectly affected biomass by altering multiple diversity and stand structure. Functional traits also directly and indirectly affected biomass. Overall, these results support niche complementarity effect and mass-ratio hypothesis. Our results indicate that biodiversity is essential for maintaining ecosystem functions of species-rich subtropical natural forests. Further, adjusting stand structure may be an effective forest management approach to increase forest carbon storage.

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Assessing Wood and Soil Carbon Losses from a Forest-Peat Fire in the Boreo-Nemoral Zone

Forests ◽

10.3390/f12070880 ◽

2021 ◽

Vol 12 (7) ◽

pp. 880

Author(s):

Andrey Sirin ◽

Alexander Maslov ◽

Dmitry Makarov ◽

Yakov Gulbe ◽

Hans Joosten

Keyword(s):

Soil Carbon ◽

Stand Structure ◽

Peat Soil ◽

Burned Area ◽

Tree Biomass ◽

Carbon Loss ◽

Forest Stand Structure ◽

Peat Fire ◽

Peat Fires ◽

Carbon Losses

Forest-peat fires are notable for their difficulty in estimating carbon losses. Combined carbon losses from tree biomass and peat soil were estimated at an 8 ha forest-peat fire in the Moscow region after catastrophic fires in 2010. The loss of tree biomass carbon was assessed by reconstructing forest stand structure using the classification of pre-fire high-resolution satellite imagery and after-fire ground survey of the same forest classes in adjacent areas. Soil carbon loss was assessed by using the root collars of stumps to reconstruct the pre-fire soil surface and interpolating the peat characteristics of adjacent non-burned areas. The mean (median) depth of peat losses across the burned area was 15 ± 8 (14) cm, varying from 13 ± 5 (11) to 20 ± 9 (19). Loss of soil carbon was 9.22 ± 3.75–11.0 ± 4.96 (mean) and 8.0–11.0 kg m−2 (median); values exceeding 100 tC ha−1 have also been found in other studies. The estimated soil carbon loss for the entire burned area, 98 (mean) and 92 (median) tC ha−1, significantly exceeds the carbon loss from live (tree) biomass, which averaged 58.8 tC ha−1. The loss of carbon in the forest-peat fire thus equals the release of nearly 400 (soil) and, including the biomass, almost 650 tCO2 ha−1 into the atmosphere, which illustrates the underestimated impact of boreal forest-peat fires on atmospheric gas concentrations and climate.

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