Wood density and tree size used as cues to locate and excavate cavities in two Colaptes woodpeckers inhabiting a threatened southern temperate forest of Argentina

Abstract. Fungal decay of heartwood creates hollows and areas of reduced wood density within the stems of living trees known as heart rot. Although heart rot is acknowledged as a source of error in forest aboveground biomass estimates, there are few datasets available to evaluate the environmental controls over heart rot infection and severity in tropical forests. Using legacy and recent data from drilled, felled, and cored stems in mixed dipterocarp forests in Sarawak, Malaysian Borneo, we quantified the frequency and severity of heart rot, and used generalized linear mixed effect models to characterize the association of heart rot with tree size, wood density, taxonomy, and edaphic conditions. Heart rot was detected in 55% of felled stems > 30 cm DBH, while the detection frequency was lower for stems of the same size evaluated by non-destructive drilling (45%) and coring (23%) methods. Heart rot severity, defined as the percent stem volume lost in infected stems, ranged widely from 0.1–82.8%. Tree taxonomy explained the greatest proportion of variance in heart rot frequency and severity among the fixed and random effects evaluated in our models. Heart rot frequency, but not severity, increased sharply with tree diameter, ranging from 56% infection across all datasets in stems > 50 cm DBH to 11% in trees 10–30 cm DBH. The frequency and severity of heart rot increased significantly in soils with low pH and cation concentrations in topsoil, and heart rot was more common in tree species associated with dystrophic sandy soils than with nutrient-rich clays. When scaled to forest stands, the percent of stem biomass lost to heart rot varied significantly with soil properties, and we estimate that 7% of the forest biomass is in some stage of heart rot decay. This study demonstrates not only that heart rot is a significant source of error in forest carbon estimates, but also that it strongly covaries with soil resources, underscoring the need to account for edaphic variation in estimating carbon storage in tropical forests.

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Evaluation of stem rot in 339 Bornean tree species: implications of size, taxonomy, and soil-related variation for aboveground biomass estimates

Biogeosciences ◽

10.5194/bg-12-5735-2015 ◽

2015 ◽

Vol 12 (19) ◽

pp. 5735-5751 ◽

Cited By ~ 9

Author(s):

K. D. Heineman ◽

S. E. Russo ◽

I. C. Baillie ◽

J. D. Mamit ◽

P. P.-K. Chai ◽

...

Keyword(s):

Tropical Forests ◽

Wood Density ◽

Aboveground Biomass ◽

Tree Species ◽

Tree Size ◽

Stem Rot ◽

Stem Volume ◽

Data Sets ◽

Related Variation ◽

Source Of Error

Abstract. Fungal decay of heart wood creates hollows and areas of reduced wood density within the stems of living trees known as stem rot. Although stem rot is acknowledged as a source of error in forest aboveground biomass (AGB) estimates, there are few data sets available to evaluate the controls over stem rot infection and severity in tropical forests. Using legacy and recent data from 3180 drilled, felled, and cored stems in mixed dipterocarp forests in Sarawak, Malaysian Borneo, we quantified the frequency and severity of stem rot in a total of 339 tree species, and related variation in stem rot with tree size, wood density, taxonomy, and species' soil association, as well as edaphic conditions. Predicted stem rot frequency for a 50 cm tree was 53 % of felled, 39 % of drilled, and 28 % of cored stems, demonstrating differences among methods in rot detection ability. The percent stem volume infected by rot, or stem rot severity, ranged widely among trees with stem rot infection (0.1–82.8 %) and averaged 9 % across all trees felled. Tree taxonomy explained the greatest proportion of variance in both stem rot frequency and severity among the predictors evaluated in our models. Stem rot frequency, but not severity, increased sharply with tree diameter, ranging from 13 % in trees 10–30 cm DBH to 54 % in stems ≥ 50 cm DBH across all data sets. The frequency of stem rot increased significantly in soils with low pH and cation concentrations in topsoil, and stem rot was more common in tree species associated with dystrophic sandy soils than with nutrient-rich clays. When scaled to forest stands, the maximum percent of stem biomass lost to stem rot varied significantly with soil properties, and we estimate that stem rot reduces total forest AGB estimates by up to 7 % relative to what would be predicted assuming all stems are composed strictly of intact wood. This study demonstrates not only that stem rot is likely to be a significant source of error in forest AGB estimation, but also that it strongly covaries with tree size, taxonomy, habitat association, and soil resources, underscoring the need to account for tree community composition and edaphic variation in estimating carbon storage in tropical forests.

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Inter-specific variations in tree stem methane and nitrous oxide exchanges in a tropical rainforest

10.5194/egusphere-egu21-13260 ◽

2021 ◽

Author(s):

Warren Daniel ◽

Clément Stahl ◽

Benoît Burban ◽

Jean-Yves Goret ◽

Jocelyn Cazal ◽

...

Keyword(s):

Nitrous Oxide ◽

Tropical Forest ◽

Tropical Forests ◽

Wood Density ◽

Tree Species ◽

Pore Space ◽

Tree Size ◽

Tropical Tree ◽

Wet Season ◽

Ghg Fluxes

Tropical forests are the most productive terrestrial ecosystems, global centres of biodiversity and important participants in the global carbon and water cycles. The Amazon, which is the most extensive tropical forest, can contain more than 600 trees (diameter at breast height above 10 cm) and up to 200 tree species in only one hectare of forest. In upland forest, tropical soils are known to be a methane (CH4) sink and a weak source of nitrous oxide (N2O), which are both major greenhouse gases (GHG). Most of researches on GHG fluxes have been conducted on the soil compartment but recent works reported that tree stems of some tropical forests can be a substantial source of CH4 and, a to lesser extend of N2O. Tropical tree stems can act as conduits of soil-produced GHG but biophysical mechanisms controlling GHG fluxes and differences among tree species are not yet fully understood.In order to quantify CH4 and N2O fluxes of different tropical tree species, we took gas samples in 101 mature tree stems of twelve species with the manual chamber technique during the wet season 2020, in a French Guiana forest. Tree species were selected because of their abundance and their habitat preference. We chose trees belonging to two contrasted forest habitats, the hill-top and hill-bottom, which are respectively characterized by aerobic conditions and seasonal anaerobic conditions. Simultaneously with sampling GHG, we measured bark moisture and tree diameter. Four tree species were found in both habitats whereas the eight others were only present in one of these two habitats.Among the 101 tree stems, 78.6% were net sources of CH4 with a greater proportion in hill-bottom than hill-top. Overall, stem CH4 fluxes were significantly and positively correlated with the wood density (&#967;2 = 28.0; p < 0.01; N = 75) but neither with the habitat, bark moisture or tree size. We found a significant effect of the tree species on stem CH4 fluxes (F = 3.7, p < 0.001) but no interactions between the tree species and habitats.Among 43.0% of the stem N2O fluxes that were different from zero, half were from trees that were net sources of N2O mainly located in hill-top. Stem N2O fluxes are not significantly correlated with habitat, as also with the tree size, wood density or bark moisture. Unlike stem CH4 fluxes, tree species did not significantly influence stem N2O fluxes.Our study revealed that, in tropical forest, spatial variations in GHG fluxes would not only depend on soil water conditions, but also on tree species. Specific tree traits such as the wood density can favour stem CH4 emissions by providing more or less effective pore space for CH4 diffusion but seems to have a limited influence on stem N2O fluxes maybe because of the lower diffusive and ebullitive transport of N2O compared to CH4. Further investigation linking tree species traits and tree GHG fluxes are, however, necessary to elucidate the processes and mechanisms behind tree CH4 and N2O exchanges.

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Fire-induced tree mortality in a neotropical forest: the roles of bark traits, tree size, wood density and fire behavior

Global Change Biology ◽

10.1111/j.1365-2486.2011.02533.x ◽

2011 ◽

Vol 18 (2) ◽

pp. 630-641 ◽

Cited By ~ 149

Author(s):

Paulo M. Brando ◽

Daniel C. Nepstad ◽

Jennifer K. Balch ◽

Benjamin Bolker ◽

Mary C. Christman ◽

...

Keyword(s):

Wood Density ◽

Tree Mortality ◽

Fire Behavior ◽

Tree Size ◽

Neotropical Forest

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Variations in temperate forest stem biomass ratio along three environmental gradients are dominated by interspecific differences in wood density

Plant Ecology ◽

10.1007/s11258-020-01106-0 ◽

2021 ◽

Author(s):

Baptiste Kerfriden ◽

Jean-Daniel Bontemps ◽

Jean-Michel Leban

Keyword(s):

Wood Density ◽

Temperate Forest ◽

Environmental Gradients ◽

Stem Biomass ◽

Interspecific Differences ◽

Biomass Ratio

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Effects of Wood Hydraulic Properties on Water Use and Productivity of Tropical Rainforest Trees

Frontiers in Forests and Global Change ◽

10.3389/ffgc.2020.598759 ◽

2021 ◽

Vol 3 ◽

Author(s):

Martyna M. Kotowska ◽

Roman M. Link ◽

Alexander Röll ◽

Dietrich Hertel ◽

Dirk Hölscher ◽

...

Keyword(s):

Flux Density ◽

Water Use ◽

Wood Density ◽

Wood Anatomy ◽

Tree Size ◽

Plant Performance ◽

Strong Positive Correlation ◽

Sap Flux ◽

Sap Flux Density ◽

Stem Increment

The efficiency of the water transport system in trees sets physical limits to their productivity and water use. Although the coordination of carbon assimilation and hydraulic functions has long been documented, the mutual inter-relationships between wood anatomy, water use and productivity have not yet been jointly addressed in comprehensive field studies. Based on observational data from 99 Indonesian rainforest tree species from 37 families across 22 plots, we analyzed how wood anatomy and sap flux density relate to tree size and wood density, and tested their combined influence on aboveground biomass increment (ABI) and daily water use (DWU). Results from pairwise correlations were compared to the outcome of a structural equation model (SEM). Across species, we found a strong positive correlation between ABI and DWU. Wood hydraulic anatomy was more closely related to these indicators of plant performance than wood density. According to the SEM, the common effect of average tree size and sap flux density on the average stem increment and water use of a species was sufficient to fully explain the observed correlation between these variables. Notably, after controlling for average size, only a relatively small indirect effect of wood properties on stem increment and water use remained that was mediated by sap flux density, which was significantly higher for species with lighter and hydraulically more efficient wood. We conclude that wood hydraulic traits are mechanistically linked to water use and productivity via their influence on sap flow, but large parts of these commonly observed positive relationships can be attributed to confounding size effects.

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