Fine Woody Debris Research Articles

Fungal and beetle diversity in deciduous fine woody debris in spruce-dominated forests in relation to substrate quantity and quality

AbstractDeciduous fine woody debris (DFWD) is a common deadwood substrate type in boreal conifer-dominated forests, but it is usually present in low volumes, and its importance for deadwood dependent biodiversity is poorly understood. In this study, we investigated how DFWD-associated fungal and beetle diversity depends on local substrate availability and quality, and how species diversity differs between DFWD and coarse deciduous deadwood (birch logs) in boreal mixed spruce-dominated forests in southern Finland. We studied 25 forest plots (each 0.16 ha), measuring and sampling all pieces of DFWD with a diameter of 2–5 cm and minimum length of 50 cm. Wood-inhabiting fungi were surveyed from wood samples by DNA metabarcoding and saproxylic beetles were surveyed by bark sieving. Our results showed a clear positive relationship between DFWD abundance and the diversity of fungi and beetles. Tree species and decay class diversity were not important in explaining fungal and beetle diversity or community composition, possibly due to low degree of variation in DFWD quality among the study plots. DFWD hosted more diverse fungal assemblages than birch logs, including species of conservation concern, while no red-listed beetle species were observed on DFWD. Overall, species assemblages associated with fine and coarse deciduous deadwood were non-nested. Thus, DFWD represents a non-redundant complementary deadwood resource type alongside coarse deciduous deadwood in boreal forests.

Downed woody debris varies with climate and harvesting treatment in Douglas-fir forests of British Columbia, Canada

Downed woody debris is important for biodiversity, forest regeneration, and carbon, nutrient, and water cycling, and past studies have examined how the coarse fraction is affected by climate or harvesting. In a field study in Douglas-fir dominated forests, we expand existing knowledge by investigating the interacting effects of climate and harvesting on downed woody debris of all sizes. Across a 900-km long latitudinal gradient in British Columbia, we found that coarse woody debris (CWD, >7.5 cm diameter) in humid climates contained 700% greater carbon stocks, had 500% greater volume, and was more diverse than in arid climates. Pre- and post-harvest, small and fine woody debris comprised a higher proportion of total woody debris carbon stocks in arid than moist climates, especially after clearcutting and seed tree treatments. Harvesting generally decreased total CWD volume, but it was not depleted on any site. Harvesting substantially reduced the volume of large, highly decomposed CWD except at the two most arid sites, and losses of large CWD increased with increasing tree removal. These losses were accompanied by a pulse of fresh, small diameter CWD and SWD which are short-term organic nutrient sources but have less habitat value than larger pieces and contribute to fuel loads. Because CWD was less abundant in arid than humid mature forests, care must be taken on arid sites to avoid its depletion during harvesting, especially clearcutting, where future woody debris inputs will not occur for decades.

Adding fine woody debris accelerates the turnover of soil carbon pool in high-latitude urban plantations in China

Adding fine woody debris accelerates the turnover of soil carbon pool in high-latitude urban plantations in China

Patterns of deadwood amount and deadwood diversity along a natural forest recovery gradient from agriculture to old-growth lowland tropical forests

AbstractDeadwood is a key component of nutrient cycling in natural tropical forests, serving as a globally important carbon storage and habitat for a high number of species. The conversion of tropical forests to agriculture modifies deadwood pools, but we know little about deadwood dynamics in forests recovering from human disturbance. Here we quantified the volume and diversity of coarse woody debris (CWD, ≥ 7 cm diameter) and the mass of fine woody debris (FWD, < 7 cm) along a chronosequence of natural forest recovery in the lowlands of the Ecuadorian Chocó region. We sampled forest plots ranging from 1–37 years of recovery post-cessation of agricultural use as either cacao plantation or cattle pasture, as well as actively managed cacao plantations and cattle pastures, and old-growth forests. In contrast to our expectation, we found no significant increase in deadwood volume with recovery time. The diversity in size, decay stage and type of CWD increased along the recovery gradient, with no effect of previous land use type. The mass of FWD increased overall across the recovery gradient, but these results were driven by a steep increase in former pastures, with no change observed in former cacao plantations. We suggest that the range of sizes and decomposition stages of deadwood found in these two major tropical agricultural systems could provide suitable resources for saproxylic organisms and an overlooked carbon storage outside old-growth forests. Our estimates of deadwood in agricultural systems and recovering forests can help improve global assessments of carbon storage and release in the tropics.

Spatial Analyses for Fine Woody Debris Volume Stock in the Hyrcanian Research Forest of Kheyrood-Kenar

Spatial Analyses for Fine Woody Debris Volume Stock in the Hyrcanian Research Forest of Kheyrood-Kenar

Production of greenhouse gases by logging residue in boreal clear-cut forests

AbstractForest deadwood is an important carbon reserve, estimated to contain 8% of the total forest carbon. This type of woody debris is recognized as a source of carbon dioxide (CO2), as the carbon is released back into the atmosphere by microbial decomposition. Production of methane (CH4) and nitrous oxide (N2O) has also been reported. In managed forests, logging residues form a major source of fine deadwood, but its role in the greenhouse gas exchange of forest ecosystems is poorly understood. We studied the greenhouse gas production of spruce and birch left-over fine woody debris and estimated the residence time of these residues at 18 spruce-dominated boreal forest sites in Central Finland. The study areas consisted of clear-cut forest stands, totally covering approximately 47 hectares, with logging residue ages varying between 0 and 10 years. The research was carried out over eight months from May to December 2019. We observed that CO2 dominated the greenhouse gas production of the logging residues, with the production being regulated by air temperature, tree species, residue age, and wood moisture. Emission of CO2 continued throughout the research period with a clear seasonal pattern. Production of CH4 and N2O was also observed, but not in climatically-relevant amounts. Deadwood half-life was estimated at 18 years for spruce and 9 years for birch. Our study demonstrates that logging residues form a mid-term carbon reserve and suggests that global warming could reduce the lifetime of the residues as a result of elevated and temperature-dependent CO2 release in the studied Myrtillus type forest stands.

How does position affect the decomposition of fine woody debris in subtropical forest?

Fine woody debris (FWD: 1 cm ≤ diameter ≤ 10 cm) may be intercepted by understory vegetation (including the branches of canopy trees). However, the decay dynamics of aerial FWD are often overlooked. In this study, we collected wood from four different tree species (Platycarya strobilacea, Lithocarpus glaber, Pinus massoniana, and Cryptomeria japonica) from four forests in subtropical China, and the mesh bag method was used to measure the remaining mass and microbial respiration by reciprocally transplanting mesh bags filled with different species among the four forests. The main objectives of this study were to reveal the influence of position (the ground and the air) on the decay rates of FWD and the home-field advantage (HFA) effect during a two-year experimental period. Irrespective of the experimental periods and decay fields, the mass loss of FWD was significantly higher on the ground (58.05%) than in the air (45.74%), and the microbial respiration of wood was significantly higher on the ground (18.87 μg CO2 h−1 g−1) than in the air (7.79 μg CO2 h−1 g−1). Microbial respiration was negatively correlated with wood remaining mass on the ground during the entire decay period and in the air only during the late decay period. The HFA effect was observed only on the ground (5.03–23.86%). Our study highlights that soil contact predominantly regulated the decomposition patterns and the HFA effect of fine woody debris and suggests that we should not neglect the decay of fine woody debris in the air due to the interception of understory vegetation in subtropical Chinese forests.

Molecular composition and the impact of fuel moisture content on fresh primary organic aerosol emissions during laboratory combustion of Ponderosa pine needles.

Pine needles represent an important fuel source in coniferous forest systems in the western United States. During forest fires, they can be easily ignited and help sustain flame on the ground. In this study, a comprehensive chemical analysis was conducted to examine oxygenated organic compounds (OOCs) present in PM2.5 formed from burning dry and moist ponderosa pine needles (PPN) in the presence and absence of fine woody debris (FWD). The effect of fuel moisture content (FMC), a key parameter that influence smoke formation, has not received much attention. Therefore, we also investigated the effect of FMC on PM2.5 formation and its composition. Thirty three experiments were conducted at the US Forest Service Fire Science Laboratory. PM2.5 was collected onto 47 mm Teflon filters, and silylated extracts were analyzed by gas chromatography-mass spectrometry. More than fifty OOCs were identified, including levoglucosan and mannosan; n-dodecanoic acid and n-hexadecanoic acid; dihydroabietic acid, and dehydroabietic acid; and a series of intermediate volatile and semivolatile organic compounds. Mass spectra of a wide variety of compounds in electron and chemical ionization mode are provided. Most of these OOCs were identified in this study for the first time in PPN aerosol, although some were previously reported in pine wood and other biomass burning aerosol. Our results show significant changes in the composition and abundance of particles depending on the amount and type of PPN burned. When compared with dry PPN condition, moist PPN showed decreased emissions of PM2.5 and OOCs, due likely to the presence of water in the system that partially suppressed the production of OOCs. Incorporating pine needles in atmospheric models as a contributor to smoke particles generated during forest fires is an essential step towards reducing the current uncertainties regarding the influence of these aerosols on chemical/air mass characteristics, regional meteorology, and the climate.

Biomass accumulation in trees and downed wood in northern hardwood forests: Repeated measures of a successional chronosequence in New Hampshire, USA

Successional, second-growth forests dominate much of eastern North America; thus, patterns of biomass accumulation in standing trees and downed wood are of great interest for forest management and carbon accounting. The timing and magnitude of biomass accumulation in later stages of forest development are not fully understood. We applied a “chronosequence with resampling” approach to characterize live and dead biomass accumulation in 16 northern hardwood stands in the White Mountains of New Hampshire. Live aboveground biomass increased rapidly and leveled off at about 350 Mg/ha by 145 years. Downed wood biomass fluctuated between 10 and 35 Mg/ha depending on disturbances. The species composition of downed wood varied predictably with overstory succession, and total mass of downed wood increased with stand age and the concomitant production of larger material. Fine woody debris peaked at 30–50 years during the self-thinning of early successional species, notably pin cherry. Our data support a model of northern hardwood forest development wherein live tree biomass accumulates asymptotically and begins to level off at ∼140–150 years. Still, 145-year-old second-growth stands differed from old-growth forests in their live ( p = 0.09) and downed tree diameter distributions ( p = 0.06). These patterns of forest biomass accumulation would be difficult to detect without a time series of repeated measurements of stands of different ages.

Aradidae (Hemiptera: Heteroptera) Emergent from Coarse and Fine Woody Debris in Louisiana

Aradidae (Hemiptera: Heteroptera) Emergent from Coarse and Fine Woody Debris in Louisiana

Midstory removal of encroaching species has minimal impacts on fuels and fire behavior regardless of burn season in a degraded pine-oak mixture

Anthropogenic fire exclusion has contributed to forest structural and compositional shifts, resulting in the encroachment of shade-tolerant, often fire-sensitive and/or opportunistic species throughout forest ecosystems. In the central and eastern U.S., encroaching species often exhibit fire-suppressing leaf litter and crown traits, reducing prescribed fire efficacy to restore and maintain fire-dependent mixed pine (Pinus spp.) and oak (Quercus spp.) forests. Despite fire’s natural role in these forests, management using prescribed fire alone is unlikely to reverse encroachment impacts due to the degree of forest change since fire exclusion. Consequently, additional management techniques (e.g., chemical, mechanical) are often combined with fire to ensure persistence of pine-oak mixtures and their associated ecosystem services. In current-day degraded pine-oak mixtures in the southeastern U.S., where no one species represents > 75% dominance by stand basal area, encroaching species (e.g., Liquidambar styraciflua, Quercus nigra) commonly form a dense midstory and occupy overstory positions. To quantify how encroaching species in degraded mixed pine-oak forests impact fuels, canopy cover, and seasonal fire behavior, we thinned the midstory (<20 cm DBH) of all non-pyrophytic species in 12 0.10-ha blocks within a mixed pine-oak stand at the Mary Olive Thomas Demonstration Forest (Auburn, Alabama, USA) in July 2021. Midstory thinning reduced basal area by 6.7 m2 ha−1 and canopy cover by 9.1%. In general, midstory thinning reduced shrub and fine woody debris fuel loads while having no impact on herbaceous, leaf litter, and duff fuel loads. When compared to pre-treatment levels, midstory thinning increased the relative proportion of pine leaf litter contribution to the fuelbed by 10.9% while reducing that of encroaching species by 11.4%. Despite changes to residual basal area, canopy cover, and leaf litter contribution, midstory thinning had no statistical impact on fire behavior, regardless of burn season. Early (January) and late dormant season (April) experimental fires had higher fireline intensities, consumed more surface fuels, had faster rates of spread, and higher average maximum temperatures compared to growing season (September) fires. We also noted an increase in these fire parameters with increased pine litter contribution to the fuelbed. In degraded pine-oak mixtures where encroaching species now occupy overstory canopy positions, we recommend investigating the efficacy of more intense thinning treatments that remove overstory individuals with known fire-suppressing traits to have a larger impact on canopy openness, fuels, and fire behavior.

Leaf litter combustion properties of Central European tree species

AbstractTemperate forests of Central Europe are exposed to increasing fire risk. However, little is known about combustion properties of leaf litter, which plays an important role in the spread of surface fires. We used cone calorimetry to compare combustion properties of leaf litter samples from seven common tree species of Central European forests by reconstructing a litter layer of original depth in sample holders with a size of 10 cm × 10 cm. In addition to mono-specific leaf litter beds, combustion experiments included mixtures of different litter types, mixtures of litter and bryophytes and one mixture of litter and fine woody debris, totalling to 13 different setups (i.e. litter types). Recorded combustion properties included ignitability, flaming duration and heat release. Differences in combustion properties were analysed using analyses of variance followed by pairwise post-hoc tests. Combustion properties mainly differed between different litter types (broadleaf, pine needle, short needle). Highest total and peak heat release were observed for Scots pine (Pinus sylvestris), while peak heat release rates showed only minor differences for litter of the remaining species. Broadleaf litter was characterized by highest ignitability. For short-needle litter, we observed long flaming duration and incomplete combustion, resulting in the lowest total heat release on a sample mass basis. For litter mixtures of pine and broadleaf litter, we observed lower peak heat release rates in comparison to mono-specific pine litter. Mosses reduced peak heat release rates and increased the proportion of unburned biomass. However, the magnitude of this effect differed between bryophyte species included in the mixtures. The addition of fine woody debris strongly increased total heat release, highlighting the importance of fine woody fuels for fire behaviour. The results of this study provide valuable baseline information on combustion behaviour of leaf litter from Central European forests. Due to the limitations of laboratory combustion experiments to reproduce conditions of real forest fires, there is a need for future field studies investigating fire behaviour under natural conditions.

Canopy and surface fuel estimations using RPAS and ground-based point clouds

Abstract Forest management activities intended to reduce wildfire risk rely on accurate characterizations of the amount and arrangement of canopy and surface fuels. Metrics that describe these fuels are typically estimated with various systems that transform plot-level field data into metrics that can be used within fire behaviour models. Remote sensing data have long been used to estimate these metrics across large spatial scales, but more advanced, high-density point clouds have the potential to estimate these metrics with higher accuracy. This study collected LiDAR and digital aerial photogrammetric (DAP) point clouds from a remotely piloted aerial system (RPAS), as well as mobile laser scanning (MLS) point clouds from a mobile ground-based system, and compared their ability to estimate fuel metrics. This involved the extraction of predictor variables from each point cloud, of which small subsets were used to estimate various fuel metrics. These included six overstory canopy metrics (stand height, canopy cover, tree density, canopy fuel load, canopy bulk density and canopy base height), three diameter at breast height (DBH)–related metrics (stand density index, basal area and quadratic mean diameter) and three surface fuel metrics (total woody debris (TWD), coarse woody debris (CWD) and fine woody debris (FWD)). Overall, canopy metrics were estimated most accurately by the RPAS LiDAR models, although none of the point clouds were able to accurately estimate DBH-related metrics. For the other six canopy metrics, RPAS LiDAR models had an average R2 value of 0.70; DAP – 0.63 and MLS – 0.63. CWD (&amp;gt;7 cm) and TWD loads were estimated most accurately by the MLS models (average R2 values – 0.70), followed by the RPAS LiDAR – 0.38 and DAP – 0.13. None of these models were able to accurately estimate FWD loads (≤7 cm in diameter), with the three types of point clouds having a maximum R2 value of 0.08. Overall, this research shows the relative ability of three types of high-density point clouds to estimate metrics relevant for fire behaviour modeling.

Characterizing ground and surface fuels across Sierra Nevada forests shortly after the 2012–2016 drought

The 2012–2016 hotter drought in the Sierra Nevada, California, USA led to the mortality of millions of trees. This disruption to the disturbance regime is an example of how climate extremes can exacerbate current and future wildfire risks. In this study, we used data from an extensive network of forest plots across 13 different sites in the Sierra Nevada to characterize ground (i.e., duff) and surface fuels and their potential drivers shortly after the drought (2016–2018), but before snag (standing dead tree) fall associated with this massive tree mortality event occurred. Overall, we found high biomass of fuels for most sites (138.2 ± 21.7 Mg ha−1, Mean ± 95 % CI), especially in areas lacking recent fire or active management, with values up to five times higher than estimates for pre-settlement conditions for mixed-conifer forests in the region. Four major groups of forest overstory structure were identified with some distinct fuel characteristics. These ranged from a cluster of ponderosa pine (Pinus ponderosa Douglas ex Lawson)-dominated plots with the highest density of snags, lowest live tree basal area, and lowest total ground and surface fuel biomass (mean = 90.1 Mg ha−1) to a group of giant sequoia (Sequoiadendron giganteum (Lindl.) J. Buchholz)-dominated plots with the highest live tree basal area and highest total fuel biomass (mean = 547.6 Mg ha−1). Although we found relatively weak relationships between forest characteristics and fuel loads, their inclusion in a model selection framework that also considered biophysical variables and disturbance history explained>80 % of the observed variation in litter + fine woody debris loads. The baseline fuel conditions described here will not only inform the management of drought-impacted forests in the Sierra Nevada, but also help identify key drivers of fuel succession in a changing environment.

MycoPins: a metabarcoding-based method to monitor fungal colonization of fine woody debris.

The MycoPins method described here is a rapid and affordable protocol to monitor early colonization events in communities of wood-inhabiting fungi in fine woody debris. It includes easy to implement field sampling techniques and sample processing, followed by data processing, and analysis of the development of early dead wood fungal communities. The method is based on fieldwork from a time series experiment on standard sterilized colonization targets followed by the metabarcoding analysis and automated molecular identification of species. This new monitoring method through its simplicity, moderate costs, and scalability paves a way for a broader and scalable project pipeline. MycoPins establishes a standard routine for research stations or regularly visited field sites for monitoring of fungal colonization of woody substrates. The routine uses widely available consumables and therefore presents a unifying method for monitoring of fungi of this type.

Impact of fine woody debris on surface water run-off

Impact of fine woody debris on surface water run-off

Allometric equations and wood density parameters for estimating aboveground and woody debris biomass in Cajander larch (Larix cajanderi) forests of northeast Siberia

Abstract. Boreal forests are particularly vulnerable to climate warming, which increases the occurrence of natural disturbances, such as fires and insect outbreaks. It is therefore essential to better understand climate-induced changes in boreal vegetation dynamics. This requires accurate estimates of variations in biomass across regions and time. This remains challenging in the extensive larch forests of northeast Siberia because of the paucity of allometric equations and physical properties of woody debris needed for quantifying aboveground biomass pools from field surveys. Our study is the first to present values of mean squared diameter (MSD) and specific gravity that can be used to calculate fine dead and downed woody debris loads in Cajander larch (Larix cajanderi) forests using the line-intersect sampling approach. These values were derived from field measurements collected in 25 forest stands in the Republic of Sakha, Russia, and compared with values reported for other prevalent boreal tree species. We developed allometric equations relating diameter at breast height (DBH, at 1.3 m) to stem wood, stem bark, branches, foliage, and aboveground biomass based on measurements of 63 trees retrieved from previous studies. Differences between our allometric models and existing equations were assessed in predicting larch aboveground biomass in 53 forest stands sampled in the Republic of Sakha. We found that using fine woody debris (FWD) parameters from other boreal tree species and allometric equations developed in other regions may result in significantly lower biomass estimates in larch-dominated forests of northeast Siberia. The FWD parameters and allometric equations presented in our paper can be used to refine estimates of aboveground biomass in Cajander larch forests in northeast Siberia.

Effects of differences in aboveground dead organic matter types on the stand‐scale necromass and CO2 efflux estimates in a subtropical forest in Okinawa Island, Japan

AbstractDead organic matter (DOM), which consists of leaf litter, fine woody debris (FWD; &lt;3 cm diameter), downed coarse woody debris (CWDlog), and standing or suspended coarse woody debris (CWDsnag), contributes to forest carbon cycling; however, few studies have considered effects of differences in DOM types on the stand‐scale estimates of carbon stocks of necromass and CO2 efflux (Rstand). This study investigated characteristics of necromass and Rstand in a subtropical forest in Okinawa Island, Japan, to quantify the effect of DOM type on total necromass, total Rstand, and estimate error of total necromass and Rstand. The CWDsnag accounted for the highest proportion (54%) of total necromass (1499.7 g C m−2), followed by CWDlog (24%), FWD (11%), and leaf litter (11%). Leaf litter accounted for the highest proportion (37%) of total Rstand (340.6 g C m−2 year−1), followed by CWDsnag (25%), CWDlog (20%), and FWD (17%). The CWDsnag was distributed locally with 173% coefficient of variation for necromass, which was twofold higher than those of leaf litter and FWD (72%–73%). The potential error in CWD accounted for 99% and 79% estimate error for total necromass and Rstand, respectively. For the estimates of CWDsnag and CWDlog necromass with the estimates error of &lt;10% in this study area, sampling areas of ≥28,750 m2 and ≥2058–42,875 m2, respectively, were required. Our results showed that CWD considerably contributed to stand‐scale carbon stocks and efflux among aboveground DOM in this forest, resulting in a major source of errors in the stand‐scale estimates.

Fungal Community Development in Decomposing Fine Deadwood Is Largely Affected by Microclimate.

Fine woody debris (FWD) represents the majority of the deadwood stock in managed forests and serves as an important biodiversity hotspot and refuge for many organisms, including deadwood fungi. Wood decomposition in forests, representing an important input of nutrients into forest soils, is mainly driven by fungal communities that undergo continuous changes during deadwood decomposition. However, while the assembly processes of fungal communities in long-lasting coarse woody debris have been repeatedly explored, similar information for the more ephemeral habitat of fine deadwood is missing. Here, we followed the fate of FWD of Fagus sylvatica and Abies alba in a Central European forest to describe the assembly and diversity patterns of fungal communities over 6 years. Importantly, the effect of microclimate on deadwood properties and fungal communities was addressed by comparing FWD decomposition in closed forests and under open canopies because the large surface-to-volume ratio of FWD makes it highly sensitive to temperature and moisture fluctuations. Indeed, fungal biomass increases and pH decreases were significantly higher in FWD under closed canopy in the initial stages of decomposition indicating higher fungal activity and hence decay processes. The assembly patterns of the fungal community were strongly affected by both tree species and microclimatic conditions. The communities in the open/closed canopies and in each tree species were different throughout the whole succession with only limited convergence in time in terms of both species and ecological guild composition. Decomposition under the open canopy was characterized by high sample-to-sample variability, showing the diversification of fungal resources. Tree species-specific fungi were detected among the abundant species mostly during the initial decomposition, whereas fungi associated with certain canopy cover treatments were present evenly during decomposition. The species diversity of forest stands and the variability in microclimatic conditions both promote the diversity of fine woody debris fungi in a forest.

Aboveground Deadwood Biomass and Composition Along Elevation and Land-Use Gradients at Mount Kilimanjaro

Deadwood is an important structural and functional component of forest ecosystems and biodiversity. As deadwood can make up large portions of the total aboveground biomass, it plays an important role in the terrestrial carbon (C) cycle. Nevertheless, in tropical ecosystems and especially in Africa, quantitative studies on this topic remain scarce. We conducted an aboveground deadwood inventory along two environmental gradients—elevation and land use— at Mt. Kilimanjaro, Tanzania. We used a huge elevation gradient (3690 m) along the southern slope of the mountain to investigate how deadwood is accumulated across different climate and vegetation zones. We also compared habitats that differed from natural forsts in land-use intensity and disturbance history to assess anthropogenic influence on deadwood accumulation. In our inventory we distinguished coarse woody debris (CWD) from fine woody debris (FWD). Furthermore, we calculated the C and nitrogen (N) content of deadwood and how the C/N ratio varied with decomposition stages and elevation. Total amounts of aboveground deadwood ranged from 0.07 ± 0.04 to 73.78 ± 36.26 Mg ha–1 (Mean ± 1 SE). Across the elevation gradient, total deadwood accumulation was highest at mid-elevations and reached a near-zero minimum at very low and very high altitudes. This unimodal pattern was mainly driven by the corresponding amount of live aboveground biomass and the combined effects of decomposer communities and climate. Land-use conversion from natural forests into traditional homegardens and commercial plantations, in addition to frequent burning, significantly reduced deadwood biomass, but not past selective logging after 30 years of recovery time. Furthermore, we found that deadwood C content increased with altitude. Our study shows that environmental gradients, especially temperature and precipitation, as well as different anthropogenic disturbances can have considerable effects on both the quantity and composition of deadwood in tropical forests.