Small-sized Trees Research Articles

TREE SPECIES DIVERSITY AND ETHNOBOTANY OF DEGRADED PEAT SWAMP FOREST IN CENTRAL KALIMANTAN

KALIMA, T., SUHARTI, S., SUMARHANI & TRETHOWAN, L. A. 2020. Tree species diversity and ethnobotany of degraded peat swamp forest in Central Kalimantan. Reinwardtia 19(1): 27‒54. ‒‒ Most peat swamp forest has been degraded. This has resulted in decline of its biodiversity. The objective of this study was to identify the composition, diversity, and plants used by local people in Bagantung swamp forest. The study was conducted on degraded peat swamp forest area in Bagantung, Mantangai Sub-District, Kapuas District, Central Kalimantan Province. The Shannon-Wiener (H’) and the Importance Value (IV) indices were used for analyzing the species diversity and the species importance across a number of forest plots. Useful tree species were identified by interviewing local villagers. There were 2,562 individual plants in 32 plots (each plot 20 m × 20 m). We identified 100 tree species and 16 non-tree species, from 74 genera, and 46 families. Myrtaceae, Sapotaceae, Ebenaceae, Dipterocarpaceae and Clusiaceae were the most dominant families. Large tree (H’=1.46) and small tree diversity was similar (H’=1.75). In both small and large tree size classes Calophyllum nodusum was the most dominant species. There were 16 tree species and two non-tree species used by local people for house and boat construction, furniture, handicrafts, medicine, and insect repellent.

Phylogenetic structure of Abies georgei var. smithii community at different spatial scales in Sygera Mountains of Tibet, China

We analyzed the phylogenetic structure of trees within six diameter classes (1-2, 2-4, 4-7, 7-11, 11-16, >16 cm) in quadrats with different size of 5 m×5 m,10 m×10 m, 20 m×20 m, 50 m×50 m, 100 m×100 m in a Abies georgei var. smithii community in a 4 hm2 stem-mapping plot located in subalpine dark coniferous forest of Sygera Mountains, southeast Tibet. In various spatial scales, both net relatedness index (NRI) and nearest taxon index (NTI) of the community were larger than zero, indicating a clustered phylogenetic structure with the largest clustering intensity at small spatial scale (5 m×5 m). Community of small-size classes were phylogenetically clustering. In large-size classes (DBH>7 cm) phylogenetic over dispersion became more common, with dispersion increased with increasing tree size under all spatial scales. The intensity of phylogenetic clustering in young trees increased with increasing spatial scales, while the intensity of over dispersion in large trees (DBH>7 cm) increased with spatial scale. Our results suggested that environmental filtering in small-size trees and competitive exclusion in large-size trees might be the main ecological processes driving community assembly in this region.

Structure of the Woody Stands of the Future Pre-Release Site of North African Ostrich (Struthiocameluscamelus(Linnaeus, 1858)) in Koutous, Niger

This study aims to investigate the composition and Important Value Index (IVI) of the woody stands of Tchillala, a 130-ha area selected for future North-African ostriches (Struthiocameluscamelus) prerelease in the Koutous region in Niger. The forest inventory method was implemented in 42 plots of 50 m x 20 m (1000 m²) for tree-level observation, using stratified random sampling. For each woody specimen, the trunk diameter, total height and crown diameter have been recorded; thespecimens with a trunk diameter smaller than 5 cm are considered as regenerations. A total of 17 woody species distributed across 10 families have been identified and most of them belongs either to the Mimosaceae (4 species) or the Tiliaceae (3 species). The plants density, domination and frequency were used to determine the IVI: Acacia tortilis and Balanitesaegyptiaca are the species with the highest IVI(118.43 and 88.28 respectively). The woody plants condition assessment has emphasized that trees have been facing natural (uprooting) and anthropogenic (cutting, pruning) threats. Consequently, the diameter class structures within the whole woody species community of Tchilala, as well as of the Acacia tortilis and Balanitesaegyptiaca, are mainly small size trees. The results of this study inform silvicultural management actions that would benefit to the North-African ostrich’establishment in Tchilala and the data collected are considered as possible indicators for long-term monitoring of habitat.

Species diversity of primary and secondary forests in Wanglang Nature Reserve

To study the availability of secondary forest for giant pandas (Ailuropoda melanoleuca), we conducted a field survey on the primary and secondary forests in Wanglang Nature Reserve. We compared these two forests based on species diversity and community structure using variance analysis and Mann-Whitney U test. Results showed that, as compared with the primary forest, the secondary forest had more woody plant species, higher tree richness, smaller tree size, smaller regeneration size, and a higher proportion of young bamboo. The secondary forest could provide enough food, species composition, and large-tree environment for giant pandas just as the primary forest does. Importantly, the secondary forest could provide more of the giant pandas’ preferred food than the primary forest, which might be the reason why giant pandas are increasingly using the secondary forest habitat. Thus, we consider the secondary forest as a viable habitat for giant pandas.

Fire Effects on Understory Forest Regeneration in Southern Amazonia

Fire in tropical forests increases tree mortality, degrades forest structure and reduces carbon stocks. Currently, there are large gaps in understanding how fire affects understory forest structure and composition, interactions with fire recurrence, and long-term impacts. Understanding these changes is critical to evaluate the present and future response of tropical forests to fire. We studied post-fire changes in understory regeneration in forests in Mato Grosso State, southern Amazonia, Brazil, aiming to answer the following questions: (i) does forest structure (basal area) and tree community composition vary with fire frequency and time since the last fire? (ii) does the response differ among strata (e.g., sapling, larger trees)? (iii) are changes in diversity associated with changes in forest structure? We surveyed trees and lianas in previously structurally intact forests that underwent selective logging, followed by different fire histories, including 5 and 16 years after once-burned, 5 years after three times burned, and unburned (control). Overall, species composition (abundance, richness and number of families) and diversity were highest for the unburned treatment and lowest for the recurrent burned areas. Fire frequency negatively affected plant structure and basal area; plants from the most frequently burned areas had more than 50% less basal area than unburned sites. Richness was positively related to basal area in the three times burned sites and in the sixteen years regenerating site for all strata. Our results demonstrate the negative influence of frequent fires on both the composition and structure of small trees in Amazonian forest. These changes to the cohort of small-sized trees may persist and have long-term impacts on forest structure, affecting the capacity and direction of forest recovery. With wildfire widespread across the region and increasing in frequency, fire may negatively affect tree diversity in remaining selectively logged forests and affect regional carbon cycling with consequences for the global vegetation carbon sink.

Competition modulates the response of growth to climate in pure and mixed Abies pinsapo subsp. Maroccana forests in northern Morocco

The effects of changes in structure and composition on the dynamics and responses of secondary forests to climate change are understudied. Secondary forests of Abies pinsapo var. maroccana are often a mosaic of patches of various development stages showing different stand structures and successional stages. We hypothesise that the structure, species composition and tree-to-tree competition of A. pinsapo stands in Talassemtane National Park (Riff in northern Morocco) modulate the potential response of these secondary forests to climate change. Nine plots representing three species mixtures were established in A. pinsapo-dominated forests, and dendrometric and dendroecological surveys were conducted. The two-parameter Weibull function was used to investigate the diameter distributions of Abies pinsapo, Pinus nigra subsp. mauritanica. Cedrus atlantica, Acer opalus, Juniperus oxycedrus and Quercus ilex for each site along the compositional gradient. We quantified changes in radial growth, response to climate and drought, and components of growth resilience. Finally, the influence of neighbourhood competition on individual tree growth was evaluated using the a competition index. Diameter distributions had an exponential, reverse-J character for A. pinsapo in pure and C. atlantica mixed stands. By contrast, A. pinsapo presented a positively-skewed diameter distribution dominated by small-sized trees in P. nigra mixed stands. There was a significant correlation between tree growth and climate on all forest types, with differing magnitudes per species. Significant precipitation-growth correlations were found for the previous autumn and winter (October, December) in A. pinsapo. Drought events reduced A. pinsapo’s resistance to subsequent droughts when growing in pure and mixed stands with C. atlantica. This decline was statistically significant by the end of the studied period (1999–2005). In contrast, mixed forests showed the highest recovery after drought. Successive drought events consistently reduced A. pinsapo‘s resilience to drought, regardless of species composition. In pure A. pinsapo and in A. pinsapo-C. atlantica mixed forests, competition reduced A. pinsapo’s growth, while in A. pinsapo-P. nigra mixed forests increased competition with P. nigra seemed to have a positive-to-neutral effect on A. pinsapo growth. Here, we showed that the response to climate and resilience of A. pinsapo forests could be severely influenced by structure, species composition, and competition, potentially influencing our expectations of long-term persistence of old-growth coniferous trees in the Riff mountains. Understanding forest resilience and response to changing climate has important implications towards managing and safeguarding the productivity and health of these old growth forests.

Leaf Functional Traits Are Related to Tree Size and Location in Cotton Trees Bombax malabaricum

Exploring intraspecific variation of functional traits of different sizes and ecogeographical regions is important to understand the adaptation strategies of tree populations to their environments. In this study, we explored the variation and bivariate relationships of 16 functional traits of 30 trees of Bombax malabaricum across 5 geographical regions in Hainan Island and between large- and small-sized tree populations. Principal component analysis showed that leaf thickness (LTh), guard cell length, and lower epidermis (LE) thickness were the key functional traits implicated in varying ecological strategies of B. malabaricum. A significant variation was found in the key functional traits including LE thickness, LTh, and guard cell (GCL) in populations across different ecogeographical regions. However, the LE and LTh vary significantly between the large- and small-sized trees. The LTh and LE thickness also showed an allometric relationship across different geographical regions and tree sizes. Hence, it was concluded that trees vary their ecological strategy according to their ontological developments across environments. Moreover, adaptation strategies of large-sized trees differing from small-sized ones highlight the fact that priority should be taken to conserve the trees with high age.

An Efficient Minimum-Time Cooperative Task Planning Algorithm for Serving Robots and Operators

SUMMARYWe establish an efficient minimum-time cooperative task planning algorithm for robots and operators to serve clients. This problem is an extension of the multiple traveling salesman problem and the vehicle routing problem with synchronization constraints, but it is more difficult due to the cooperative tasks of the robots and operators. To find the exact minimum-time task plan with a small tree size, we propose an efficient branch-and-bound with a good initial tree and keen complementary heuristics. Our algorithm is also effective as an approximate algorithm for the many clients problem within the capacity of the computer used. The efficiency of our algorithm is revealed via case studies: telemedical service robots and planetary exploration robots.

SPECIES-SPECIFIC BIOMASS EQUATIONS FOR SMALL-SIZE TREE SPECIES IN SECONDARY TROPICAL FORESTS

<p>Secondary tropical forests are largely dominated by small-diameter trees. Their contribution to the total stand productivity may be determinant for ecosystem functioning. However, the biomass contained in small-size trees is frequently ignored because they are rarely included in forest inventories, as well as due to the lack of biomass equations for such trees. The aim of this study was to generate specific biomass equations by tree structural components and total-tree biomass for 22 species (diameter at breast height-DBH ≤ 10 cm diameter) structurally important of secondary tropical forests in southeast Yucatán peninsula. The biomass equations were generated using two fitting approaches. First, using the additive approach where the biomass equations by structural tree components (stem, branches and foliage) were simultaneously fitted. Second, the tree-level approach where the total-tree biomass was independently fitted. We used DBH, total height (TH) and wood density (WD) as predictor variables during the fitting process. The performance of each total-tree biomass equation was compared to generalized biomass equations developed in other tropical forests. The variance explained of observed biomass across tree species were stem, 64% to 99%; branch, 24% to 95%; foliage, 35% to 94% for equations by structural tree components; while the explained variance for total tree biomass equations was between 94 to 99 %. The inclusion of TH and WD as predictor variables in the equation structure, significantly improved the goodness of fit statistics. These are the first equations developed for small-size tree species in secondary forests of Yucatán peninsula. We observed that generalized equations developed for other tropical forests, in some cases overestimated up to ~ 44.2% and in other cases underestimated up to ~ 48.4% the mean total-tree biomass. When we applied our equations to forest inventory data, they showed a better predicting performance than generalized equations. Therefore, they are reliable for estimating biomass of small-size tree species in similar forest types. Our equations could be used for biomass-carbon estimation in tropical secondary forests composed by high densities of small-size tree species; therefore, they are relevant within climate change contexts.</p>

Species diversity and composition of mangroves in Tacloban City, Philippines

This study reflects the present status of Tacloban City mangrove vegetation and would be useful for mangrove restoration program. Surveys of mangrove forests in Tacloban City were conducted from October to November 2017 in 12 selected sites. Quadrat method was used to assess the species composition and stand structure of the canopy layer, representing seaward, middle and landward zones. The mangrove forests in Tacloban City contain 23 mangrove species belonging to 12 families and 15 genera. Rhizophoraceae and Acanthaceae are the most dominating families. As per IUCN report, among the 23 species, 4 were recognized as threatened. These include the Endangered Camptostemon philippinensis, the Vulnerable Avicennia rumpiana and the Near Threatened Aegiceras floridum and Ceriops decandra. Rhizophora Apiculata is the most abundant species, followed by Sonneratia alba. Other abundant species are Avicennia officinalis, Avicennia marina and Rhizophora mucronata. The least abundant are Bruguiera gymnorrhiza, Camptostemon philippinensis and Xylocarpus granatum. The canopy layer is composed of small-sized trees with an average tree density of 1,678 per ha and stem density of 3,133 per ha. The average height and diameter are 6.15m and 8.95cm, respectively. Mangrove diversity is generally low. Shannon index of diversity value ranges from 0.762 to 1.132, with an average value of 0.914. Understory is characterized by few species of regenerants, low density and low species diversity.

Applications of computed tomography (CT) scanning technology in forest research: a timely update and review

Organic materials of woody plants are complex and show internal, structural, and morphological variations due to genetic and environmental influences. Variability can be observed in stems, branches, leaves, and roots. Nondestructive and noninvasive technologies have been proposed to assess this variability. Computed tomography (CT) scanning, originally designed for medical diagnostics, permits the measurement of wood properties in situ (e.g., wood density, moisture content, internal defects, annual growth) and crown traits that characterize branching pattern geometry and canopy space occupancy for small-sized trees. Since Wei et al.’s (2011, Can. J. For. Res. 41(11): 2120–2140, doi: 10.1139/x11-111 ) review on the assessment of wood quality for optimized manufacturing processes using a CT scanner, several important developments have occurred, motivating the preparation of an update. We provide technical clarifications about the scales of observation and resolution; report on recent studies in which CT scanning was applied with research objectives beyond wood quality assessment for an optimized manufacturing of forest products; and stress the importance of analytical procedures for the graphical and quantitative analyses of CT scanning data (images and numbers) and the need for specialized algorithms and software. With this review, readers are expected to be well informed of the avenues offered by CT scanning technology in forest research in general.

Characterizing Seedling Stands Using Leaf-Off and Leaf-On Photogrammetric Point Clouds and Hyperspectral Imagery Acquired from Unmanned Aerial Vehicle

Seedling stands are mainly inventoried through field measurements, which are typically laborious, expensive and time-consuming due to high tree density and small tree size. In addition, operationally used sparse density airborne laser scanning (ALS) and aerial imagery data are not sufficiently accurate for inventorying seedling stands. The use of unmanned aerial vehicles (UAVs) for forestry applications is currently in high attention and in the midst of quick development and this technology could be used to make seedling stand management more efficient. This study was designed to investigate the use of UAV-based photogrammetric point clouds and hyperspectral imagery for characterizing seedling stands in leaf-off and leaf-on conditions. The focus was in retrieving tree density and the height in young seedling stands in the southern boreal forests of Finland. After creating the canopy height model from photogrammetric point clouds using national digital terrain model based on ALS, the watershed segmentation method was applied to delineate the tree canopy boundary at individual tree level. The segments were then used to extract tree heights and spectral information. Optimal bands for calculating vegetation indices were analysed and used for species classification using the random forest method. Tree density and the mean tree height of the total and spruce trees were then estimated at the plot level. The overall tree density was underestimated by 17.5% and 20.2% in leaf-off and leaf-on conditions with the relative root mean square error (relative RMSE) of 33.5% and 26.8%, respectively. Mean tree height was underestimated by 20.8% and 7.4% (relative RMSE of 23.0% and 11.5%, and RMSE of 0.57 m and 0.29 m) in leaf-off and leaf-on conditions, respectively. The leaf-on data outperformed the leaf-off data in the estimations. The results showed that UAV imagery hold potential for reliably characterizing seedling stands and to be used to supplement or replace the laborious field inventory methods.

Recovery of understorey vegetation after stem-only and whole-tree harvesting in drained peatland forests

The demand for small-sized trees, logging residues, stumps, and lateral roots for energy production has increased during recent decades and therefore whole-tree harvesting (WTH) has become a more common harvesting method in forests. However, this may cause a more pronounced delay in the recovery of forest vegetation than conventional stem-only harvesting (SOH), especially in sensitive peatlands, and thus increase soil erosion. The effects of WTH have not been investigated on peatlands before this study. Recovery of understorey vegetation of drained peatland forests after two different tree harvesting methods, stem-only harvesting and whole-tree harvesting, was investigated in Eastern Finland at eight silviculturally managed peatland forests largely comprising Scots pine, Pinus sylvestris, and Norway spruce, Picea abies. In SOH, trunks only were removed from the sites whereas in WTH, tree trunks, branches, and stumps were removed. In each site, understorey vegetation (tree seedlings, dwarf shrubs, graminoids, herbs, and bryophytes) was inventoried on both mounded and unprepared soil (surfaces) on 220 permanent sample plots one and five years after harvesting. WTH had more pronounced effects on vegetation than SOH. Five to six years after the treatments, the occurrence of dwarf shrubs was lower in WTH than in SOH, whereas the cover of graminoids increased from both SOH and WTH. Soil preparation affected negatively on the recovery of peat and forest bryophytes, but positively on the recovery of some graminoid and herb species. Peat properties, e.g., pH and water table level, were found to regulate the recovery. WTH caused a longer delay on the recovery of understorey vegetation than SOH, especially if soil had been prepared. Thus, WTH cannot be recommended in drained peatland forests.

Associations between Road Density, Urban Forest Landscapes, and Structural-Taxonomic Attributes in Northeastern China: Decoupling and Implications

A better understanding on the associations between road density (RD), urban forest structural-taxonomic attributes, and landscape metrics is vital for forest ecological service evaluations and suitable management in sprawling urban areas with increasing road networks. We chose Harbin, a fast growing provincial capital city in northeast China, as a case study to address this issue. We utilized ArcGIS software (Esri, version 10.0; Redlands, CA, USA) and FRAGSTATS (V4.2.589) to digitize GF-1 images (Gaofen No.1 remote sensing images) to acquire road net characteristic information and landscape metrics of urban forests in Harbin. Together with forest structural-taxonomic attributes from a stratified random sampling survey, statistical methods such as an analysis of variance, a regression analysis, and a redundancy analysis were used to determine the road-dependent differences and to decouple the associations between them. The results indicated that road area percentages, road length/imperious surface area (ISA) ratios, road area/ISA ratios, and road cross-points sharply increased from low to heavy RD areas. This road intensification was strongly associated with increased urban forest area, patch density, and diverse patch shapes; smaller tree sizes, lower tree densities, and diverse tree species compositions were generally observed. Redundancy-based variation partitioning showed that part of the variations in structural-taxonomic attributes of forests could be explained by road intensity characteristics. In low RD (0–1.5 km/km2) regions, the road characteristics significantly affected forest characteristics (Shannon Wiener diversity index, species richness, and evenness index); however, such associations weakened with increasing forest landscape-related associations in medium to heavy RD (1.5–6 km/km2) regions. Our findings highlighted that road development is strongly associated with forest characteristics in Harbin city, and RD-dependent forest landscape regulating management could favor the maximization of forest ecological services that are related to structural and species identities.

Genetic algorithm-based hybrid approach for optimal instance selection of minimising makespan in permutation flowshop scheduling

Recently, the instance selection is getting more attention for the researchers to achieve enhanced performance of algorithms. A typical flowshop dataset can be represented in the form of a number of instances. The instances that are recorded during production process may not be a good example to learn useful knowledge. Therefore, the selection of high quality instances can be considered as a search problem and be solved by evolutionary algorithms. In this work, a genetic algorithm (GA) is proposed to select a sub-set of best instances. The selected instances are represented in the form of IF-Then else rules using a decision tree (DT) algorithm. The seed solution from DT is used as input to a scatter search (SS) algorithm for a few iterations, which acts as a local search to find the best value of the selected instances. The GA is used to select best instances in order to have a smaller tree size with good solution accuracy for minimizing makespan criterion in permutation flowshop scheduling. The computational experiments are performed with standard problems and compared against various existing literatures.

Genetic algorithm-based hybrid approach for optimal instance selection of minimising makespan in permutation flowshop scheduling

Recently, the instance selection is getting more attention for the researchers to achieve enhanced performance of algorithms. A typical flowshop dataset can be represented in the form of a number of instances. The instances that are recorded during production process may not be a good example to learn useful knowledge. Therefore, the selection of high quality instances can be considered as a search problem and be solved by evolutionary algorithms. In this work, a genetic algorithm (GA) is proposed to select a sub-set of best instances. The selected instances are represented in the form of IF-Then else rules using a decision tree (DT) algorithm. The seed solution from DT is used as input to a scatter search (SS) algorithm for a few iterations, which acts as a local search to find the best value of the selected instances. The GA is used to select best instances in order to have a smaller tree size with good solution accuracy for minimizing makespan criterion in permutation flowshop scheduling. The computational experiments are performed with standard problems and compared against various existing literatures.

Строение древостоев среднетаежных сосняков лишайниковых на европейском северо-востоке России

В статье представлены результаты, характеризующие строение древостоев среднетаежных сосняков лишайниковых на европейском северо-востоке России. Проведен статистический анализрядов распределения деревьев сосны по диаметру и высоте ствола. Установлено, что коэффициентвариации высоты в древостоях сосняков изменяется от 9 до 34 %, а асимметрия близка к нулевомузначению, что свидетельствует о почти нормальном распределении деревьев. Коэффициент вариации диаметра колеблется от 27 до 67 %, что говорит о растянутости распределения особей сосны в насаждениях по этому показателю. Показан вклад деревьев разных ступеней толщины в накопление запасов древесины древостоем. В средневозрастных и приспевающих насаждениях 41–55 % от числа деревьев и 32–41 % от объема древесины приходится на ступень толщины, соответствующую среднему диаметру дерева в древостое, и на две соседние ступени толщины. В спелых и перестойных сосняках эти величины составили 6–48 и 4–46 % соответственно, что отражает наличие нескольких поколений в древостоях на этих стадиях развития. Выявлена статистически достоверная взаимосвязь (положительная и отрицательная) между средним диаметром дерева и числом крупно- и тонкомерных деревьев, тогда как корреляции между средним диаметром дерева и запасом древесины в крупномерных и деревьях средних ступеней толщины не обнаружено. Выведено обобщенное регрессионное уравнение взаимосвязи высоты дерева от его диаметра, которое можно использовать для определения высоты деревьев среднетаежных сосняков лишайниковых на европейском северо-востоке России.

Abiotic factors modulate post-drought growth resilience of Scots pine plantations and rear-edge Scots pine and oak forests

The proportion of planted forests in the Mediterranean Basin is one of the largest in the world. These plantations are dominated by pine species and present a series of characteristics such as low elevation, high competition or small tree size that make them more vulnerable to droughts. However, quantitative assessments of their post-drought growth resilience in accordance with species, site factors and tree characteristics are lacking. In this study we sampled 164 trees at four forest sites located in the drought-prone Sierra Nevada, southeastern Spain. We compared growth responsiveness to drought in rear-edge planted vs. relic natural Scots pine (Pinus sylvestris) and coexisting Pyrenean oak (Quercus pyrenaica) stands. Our objective was to characterize and compare the different growth responses to drought between species and sites and the effect of the main physiographic factors (altitude, aspect, and slope) on these responses since the influence of these factors on post-drought resistance and resilience has received little attention to date. Our results reveal that the planted pine sites with the lowest mean growth rates displayed greater resistance during drought, and that higher altitude was associated with improved resistance and/or resilience for all species and sites. Natural pine and Pyrenean oak stands were better adapted to the dry climatic conditions of the Mediterranean region where the study was undertaken, displaying greater resistance and/or resilience and lower influence of drought on growth in comparison to stands of planted pines. These results suggest that promoting the conservation of high-elevation pine plantations and enhancing the regeneration of natural pine and oak may improve the resistance and resilience of these drought-prone forest ecosystems.

Quantifying environmental and health benefits of using woody biomass for electricity generation in the Southwestern United States

The majority of National Forests in the southwestern United States need fuels-reduction treatments that have not kept pace with tree growth and fuels accumulation. The harvested small-sized trees are commonly disposed of through pile burning on the site due to their low market values. We assessed the environmental and health benefits of using small diameter wood from the fuels-reduction treatments as a renewable energy source for electricity production to increase forest health and environmental quality. Our study area was located in northern Arizona within the Four Forest Restoration Initiative project area. We investigated eight air pollutants, projected stand conditions, calculated pollutant emissions from power generators and assessed damage costs from power production. We further used life cycle assessments to investigate emissions from feedstock production, transportation and power generation. Our life cycle assessment results indicate that the annual total damage costs of three treatment-energy scenarios, 1) no thin-coal, 2) thin & pile burning-coal, and 3) thin-bioenergy, are $978,157, $1,732,300 and $43,216, respectively. We determined that in comparison with the no-action (no thin-coal) scenario, the total environmental and health damage cost avoided by utilizing removed woody biomass for the yearly output of a 1 MW (megawatt) power plant was $934,941 annually.

Edge disturbance drives liana abundance increase and alteration of liana-host tree interactions in tropical forest fragments.

Closed‐canopy forests are being rapidly fragmented across much of the tropical world. Determining the impacts of fragmentation on ecological processes enables better forest management and improves species‐conservation outcomes. Lianas are an integral part of tropical forests but can have detrimental and potentially complex interactions with their host trees. These effects can include reduced tree growth and fecundity, elevated tree mortality, alterations in tree‐species composition, degradation of forest succession, and a substantial decline in forest carbon storage. We examined the individual impacts of fragmentation and edge effects (0–100‐m transect from edge to forest interior) on the liana community and liana–host tree interactions in rainforests of the Atherton Tableland in north Queensland, Australia. We compared the liana and tree community, the traits of liana‐infested trees, and determinants of the rates of tree infestation within five forest fragments (23–58 ha in area) and five nearby intact‐forest sites. Fragmented forests experienced considerable disturbance‐induced degradation at their edges, resulting in a significant increase in liana abundance. This effect penetrated to significantly greater depths in forest fragments than in intact forests. The composition of the liana community in terms of climbing guilds was significantly different between fragmented and intact forests, likely because forest edges had more small‐sized trees favoring particular liana guilds which preferentially use these for climbing trellises. Sites that had higher liana abundances also exhibited higher infestation rates of trees, as did sites with the largest lianas. However, large lianas were associated with low‐disturbance forest sites. Our study shows that edge disturbance of forest fragments significantly altered the abundance and community composition of lianas and their ecological relationships with trees, with liana impacts on trees being elevated in fragments relative to intact forests. Consequently, effective control of lianas in forest fragments requires management practices which directly focus on minimizing forest edge disturbance.