Environmental Science › Nature and Landscape Conservation

Forest ecology and management

Works Count: 100215

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This cluster of papers focuses on the development and improvement of allometric models for estimating biomass and carbon stocks in tropical forests. It also addresses the challenges and uncertainties associated with forest biomass estimation, including the impact of climate change on forest site productivity and the development of height-diameter models for accurate biomass estimation.

Keywords

Allometric Models; Biomass Estimation; Carbon Stocks; Tropical Forests; Tree Allometry; Forest Site Productivity; Aboveground Biomass; Tree Height-Diameter Models; Stand Density; Climate Change Impact

Adaptive Environmental Assessment and Management

1980-09-01

C. S. Holling

Journal Article Adaptive Environmental Assessment and Management Get access Edited by Holling C. S.. 1978. Witey-Interscience, Chichester-New York-Brisbane-Toronto. xviii + 377 pages, Mus. $16.50. Reviewed by Campbell Robert W., Pacific … Journal Article Adaptive Environmental Assessment and Management Get access Edited by Holling C. S.. 1978. Witey-Interscience, Chichester-New York-Brisbane-Toronto. xviii + 377 pages, Mus. $16.50. Reviewed by Campbell Robert W., Pacific Northwest Forest and Range Experiment Station, USDA Forest Service, Corvallis, Oregon 97331 Forest Science, Volume 26, Issue 3, September 1980, Pages 435–436, https://doi.org/10.1093/forestscience/26.3.435 Published: 01 September 1980

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Modelling Forest Growth and Yield: Applications to Mixed Tropical Forests

1994-01-01

Jerome K. Vanclay

This book attempts to make growth models more accessible to foresters and others interested in mixed forests, whether planted or natural. There is an increasing interest in, and controversy surrounding … This book attempts to make growth models more accessible to foresters and others interested in mixed forests, whether planted or natural. There is an increasing interest in, and controversy surrounding the use of mixed plantations and natural forests, and rational discussion and resolution of management options require reliable growth models linked to other information systems. It is my hope that this book will help researchers to build better models, and will help users to understand how the models work and thus to appreciate their strengths and weaknesses. During recent years, vast areas of natural forest, especially in the tropics, have been logged or converted to other uses. Well-meaning forest managers have often been over-optimistic in estimating forest growth and yields, and this has contributed to over-cutting in some forests. Growth models can provide objective forecasts, offering forest managers the information needed to maintain harvests within the sustainable capacity of the forest, and providing quantitative data for land use planners to make informed decisions on land use alternatives. In this way, I hope that this book will contribute to the conservation and sustainable management of natural forests in the tropics and elsewhere. This is not a How to do it manual with step-by-step instructions to build a growth model for mixed forests. Unfortunately, modelling these forests isn't that easy. There is no single way to build a model for these forests. Rather, many approaches can be used, and the best one depends on the data available, the time and expertise available to build the model, the computing resources, and the inferences that are to be drawn from the model. So instead of writing a cookbook with one or two recipes, I review and illustrate some of the many approaches available, indicate the requirements of and output from each, and highlight their strengths and limitations. The book emphasizes empirical-statistical models rather than physiological-process type models, not because they are superior, but because they have proven utility and offer immediate benefits for forest management. A more comprehensive treatment of all the options is beyond the scope of this book, which is intended to serve as a ready reference manual for those building growth models for forest management. Because of my limited linguistic ability, the material covered is more-or-less restricted to English-language material. I have not attempted to review all the published work on growth modelling (it would be a huge task), but have tried to highlight examples that may be applicable to mixed forests in tropical areas. I hope that the language and terminology used in this book will be accessible to all readers, especially those for whom English is a second language. The glossary may help to clarify some terms, and those that have a specific technical meaning are printed in italics the first time they are used. Readers should consult the glossary to clarify the meaning of these words unless they are sure of the meaning. Exercises are given at the end of each chapter to reinforce points made in the chapter. These are simple exercises, deliberately chosen so that they can be completed quickly with pen and paper or PC and spreadsheet, but within these constraints, I have tried to keep them realistic. Some exercises (e.g. 9.1 and 10.3) require more specialized statistical analyses, but many commercial statistical packages (e.g. GLIM) are suitable. Where possible, these exercises draw on real data, but some data were simulated to create interesting exercises with few data. Whilst my approach places more responsibility on the reader to choose and develop a suitable modelling methodology, I hope it will help readers gain a better understanding of modelling, which should in turn lead to better models and more reliable predictions. And I hope that better models will provide better information, greater understanding, and better management of mixed forests.

Litter Production in Forests of the World

1964-01-01

J. R. Bray , Eville Gorham

Principles of Wood Science and Technology

1968-01-01

Franz Kollmann , W. A. Côté

Computer-Assisted Quality Control in Tree-Ring Dating and Measurement

1983-01-01

Richard L. Holmes

Age-Related Decline in Forest Productivity: Pattern and Process

1997-01-01

Michael G. Ryan , Dan Binkley , James H. Fownes

Forest stand dynamics

1990-12-01

Chadwick Dearing Oliver , Bruce C. Larson

Plant Interactions and Limitations of Growth. Tree Architecture and Growth. Disturbances and Stand Development. Overview of Stand Development Patterns. Temporal and Spatial Patterns of Tree Invasion. Stand Initiation Stage: Single-Cohort … Plant Interactions and Limitations of Growth. Tree Architecture and Growth. Disturbances and Stand Development. Overview of Stand Development Patterns. Temporal and Spatial Patterns of Tree Invasion. Stand Initiation Stage: Single-Cohort Stands. Stem Exclusion Stage: Single-Cohort Stands, Single-Species Stands. Stem Exclusion Stage: Single-Cohort Stands, Mixed-Species Stands. Understory Reinitiation Stage. Old Growth Stage. Multicohort Stands: Behavior of Component Cohorts. Development of Multicohort Stands. Stand Edges, Gaps, and Clumps. Quantification of Stand Development. Forest Patterns Over Long Times and Large Areas. References. Appendix. Index.

Some Ecological Consequences of a Computer Model of Forest Growth

1972-11-01

Daniel B. Botkin , J. F. Janak , James R. Wallis

The complexity of a forest ecosystem makes difficult any attempt to synthesize knowledge about forest dynamics or to perceive the implications of information and assumptions regarding forest growth. Although digital … The complexity of a forest ecosystem makes difficult any attempt to synthesize knowledge about forest dynamics or to perceive the implications of information and assumptions regarding forest growth. Although digital computer simulation seems to offer a potential for creating a complete model of forest growth, little progress has been reported. Computer simulation has been carried out for the growth of trees in even-aged stands of a single species (Mitchell 1969), and for meteorological energy exchange in a forest canopy (Waggoner & Reifsnyder 1968). A specific simulation built directly from Hubbard Brook data has been reported (Siccama et al. 1969). Successional change in northern hardwood forests has been predicted from observed birth and death rates (Leak 1970). A conceptual model has been created for the growth of individual tree seedlings from rates of photosynthesis and the distribution of photosynthates (Ledig 1969). Computer simulation has been carried out for some aspects in a few other terrestrial ecosystems, such as productivity in a corn crop (Duncan et al. 1967); but apparently no one has successfully reproduced the major characteristics of a mixed-species, mixed-aged forest from a conceptual basis. A computer simulation of forest growth is now developed that successfully reproduces the population dynamics of the trees in a mixed-species forest of north-east North America. The simulator is designed to be used in the Hubbard Brook Ecosystem Study and to provide output in the same form as the original vegetation survey of that study (Bormann et al. 1970). However, the underlying concepts of the simulation are general. The properties of each species are derived from its entire geographic range and in theory any non-hydrophytic species whose relevant characteristics are known can be entered into the simulation. In the present version of the program, the description of the environment is restricted to those features that have been recorded for the Hubbard Brook Forest, but the relative importance attached to each environmental factor has been influenced by the environmental characteristics of the north-eastern United States. It is hoped that a wide dissemination of this simulator will encourage others to test this version with their data and hence lead to later versions of wider usefulness and applicability. The basic goal was to produce a dynamic model of forest growth, a model in which changes in the state of the forest are a function of the present state and random components. This approach has two advantages over the curve-fitting approach to forest growth: first, the simulator can be regarded as a repository for an integrated knowledge of the ecosystem; second, additional hypotheses can be formulated and tested using Monte Carlo samples of simulator runs and comparing the results with observed data. For

Critical analysis of root : shoot ratios in terrestrial biomes

2005-11-21

Karel Mokany , R. J. Raison , Anatoly Prokushkin

Abstract One of the most common descriptors of the relationship between root and shoot biomass is the root : shoot ratio, which has become a core method for estimating root … Abstract One of the most common descriptors of the relationship between root and shoot biomass is the root : shoot ratio, which has become a core method for estimating root biomass from the more easily measured shoot biomass. Previous reviews have examined root : shoot ratio data, but have only considered particular vegetation types and have not always critically reviewed the data used. Reliable root : shoot ratios are needed for a wide range of vegetation types in order to improve the accuracy of root biomass estimates, including those required for estimating the effects of land management and land use change in National Greenhouse Gas Inventories. This study reviewed root : shoot ratios in terrestrial biomes. A key facet of our analysis was a critical methodological review, through which unreliable data were identified and omitted on the basis of specific criteria. Of the 786 root : shoot ratio observations collated, 62% were omitted because of inadequate or unverifiable root sampling methods. When only the reliable data were examined, root : shoot ratios were found to be negatively related to shoot biomass, mean annual precipitation, mean annual temperature, forest stand age, and forest stand height. Although a single allometric equation derived in this study reliably predicted root biomass from shoot biomass for forests and woodlands, in general, the use of vegetation‐specific root : shoot ratios were found to be a more accurate method for predicting root biomass. When the root : shoot ratio data collated here were applied to an analysis of the global carbon budget, there was a 50% increase in estimated global root carbon stock, and a 12% increase in estimated total carbon stock of terrestrial vegetation. The use of the vegetation‐specific root : shoot ratios presented in this study is likely to substantially improve the accuracy of root biomass estimates for purposes such as carbon accounting and for studies of ecosystem dynamics.

Canopy Gaps and the Two Major Groups of Forest Trees

1989-06-01

T. C. Whitmore

Ecology and Biogeography of Pinus

2001-10-01

Richard F. Fisher

Timber management: a quantitative approach.

1983-01-01

Jerome L. Clutter , James C. Fortson , Leon V. Pienaar +2 more

GROWTH AND YIELD PREDICTION. Estimating the Volumes and Weights of Individual Trees. Evaluating Site Quality. Growing Stock and Stand Density. Predicting Growth and Yield. FINANCIAL ASPECTS OF TIMBER MANAGEMENT. Forest … GROWTH AND YIELD PREDICTION. Estimating the Volumes and Weights of Individual Trees. Evaluating Site Quality. Growing Stock and Stand Density. Predicting Growth and Yield. FINANCIAL ASPECTS OF TIMBER MANAGEMENT. Forest Finance. Taxes and Risk in the Evaluation of Forest Investments. TIMBER MANAGEMENT PLANNING. Timber Management - Some Introductory Comments. Stand-Level Management Planning. Forest-Level Management Planning: Basic Concepts. Forest-Level Management Planning: Current Techniques. Appendices. Index.

Changes in Forest Biomass Carbon Storage in China Between 1949 and 1998

2001-06-22

Jingyun Fang , Anping Chen , Changhui Peng +2 more

The location and mechanisms responsible for the carbon sink in northern mid-latitude lands are uncertain. Here, we used an improved estimation method of forest biomass and a 50-year national forest … The location and mechanisms responsible for the carbon sink in northern mid-latitude lands are uncertain. Here, we used an improved estimation method of forest biomass and a 50-year national forest resource inventory in China to estimate changes in the storage of living biomass between 1949 and 1998. Our results suggest that Chinese forests released about 0.68 petagram of carbon between 1949 and 1980, for an annual emission rate of 0.022 petagram of carbon. Carbon storage increased significantly after the late 1970s from 4.38 to 4.75 petagram of carbon by 1998, for a mean accumulation rate of 0.021 petagram of carbon per year, mainly due to forest expansion and regrowth. Since the mid-1970s, planted forests (afforestation and reforestation) have sequestered 0.45 petagram of carbon, and their average carbon density increased from 15.3 to 31.1 megagrams per hectare, while natural forests have lost an additional 0.14 petagram of carbon, suggesting that carbon sequestration through forest management practices addressed in the Kyoto Protocol could help offset industrial carbon dioxide emissions.

Long-term decline of the Amazon carbon sink

2015-03-01

Roel Brienen , Oliver L. Phillips , Ted R. Feldpausch +7 more

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A Critique of the Analytical Methods Used in Examining Decomposition Data Obtained From Litter Bags

1982-12-01

R. Kelman Wider , Gerald E. Lang

The study of plant litter decomposition in terrestrial ecosystems commonly employs litter bags to compare the loss of mass among species, among sites, and under various experimental manipulations, or to … The study of plant litter decomposition in terrestrial ecosystems commonly employs litter bags to compare the loss of mass among species, among sites, and under various experimental manipulations, or to investigate the process itself. Analysis of the resulting data is quite variable among investigators, and at times inappropriate. Two general analytical approaches to the examination of decomposition data are reviewed. Analysis of variance is useful if the intent is to compare treatment means, but does not directly test hypotheses regarding decomposition rates. If the intent is to determine rate constants, than fitting mathematical models to data is the more appropriate analysis. Single and double exponential models best describe the loss of mass over time with an element of biological realism. See full-text article at JSTOR

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Latent curve analysis

1990-03-01

William Meredith , John Tisak

BRANCH SUPPORT AND TREE STABILITY

1994-09-01

Ka ̊re Bremer

Abstract— Branch support is quantified as the extra length needed to lose a branch in the consensus of near‐most‐parsimonious trees. This approach is based solely on the original data, as … Abstract— Branch support is quantified as the extra length needed to lose a branch in the consensus of near‐most‐parsimonious trees. This approach is based solely on the original data, as opposed to the data perturbation used in the bootstrap procedure. If trees have been generated by Farris's successive approximations approach to character weighting, branch support should be examined in terms of weighted extra length needed to lose a branch. The sum of all branch support values over the tree divided by the length of the most parsimonious tree[s] provides a new index, the total support index. This index is a measure of tree stability in terms of supported resolutions, which is of prime importance in cladistic analysis.

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Mapping tree density at a global scale

2015-09-02

Thomas W. Crowther , Henry B. Glick , Kristofer Covey +7 more

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Use of Logarithmic Regression in the Estimation of Plant Biomass

1972-03-01

G. L. Baskerville

The basic assumptions of regression analysis are recalled with special reference to the use of a logarithmic transformation. The limitations imposed on inference-making by failure to comply with these assumptions … The basic assumptions of regression analysis are recalled with special reference to the use of a logarithmic transformation. The limitations imposed on inference-making by failure to comply with these assumptions are discussed and ways to avoid the limitations indicated. A systematic bias of the order of 10 to 20% which is inherent in most, if not all, prior uses of the logarithmic equation to estimate plant biomass is noted as is the correction for the bias.

A protocol for data exploration to avoid common statistical problems

2009-11-13

Alain F. Zuur , Elena N. Ieno , Chris S. Elphick

1. While teaching statistics to ecologists, the lead authors of this paper have noticed common statistical problems. If a random sample of their work (including scientific papers) produced before doing … 1. While teaching statistics to ecologists, the lead authors of this paper have noticed common statistical problems. If a random sample of their work (including scientific papers) produced before doing these courses were selected, half would probably contain violations of the underlying assumptions of the statistical techniques employed. 2. Some violations have little impact on the results or ecological conclusions; yet others increase type I or type II errors, potentially resulting in wrong ecological conclusions. Most of these violations can be avoided by applying better data exploration. These problems are especially troublesome in applied ecology, where management and policy decisions are often at stake. 3. Here, we provide a protocol for data exploration; discuss current tools to detect outliers, heterogeneity of variance, collinearity, dependence of observations, problems with interactions, double zeros in multivariate analysis, zero inflation in generalized linear modelling, and the correct type of relationships between dependent and independent variables; and provide advice on how to address these problems when they arise. We also address misconceptions about normality, and provide advice on data transformations. 4. Data exploration avoids type I and type II errors, among other problems, thereby reducing the chance of making wrong ecological conclusions and poor recommendations. It is therefore essential for good quality management and policy based on statistical analyses.

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Tree allometry and improved estimation of carbon stocks and balance in tropical forests

2005-06-22

Jérôme Chave , Christophe Andalo , Sandra Brown +7 more

Determination of Deforestation Rates of the World's Humid Tropical Forests

2002-08-09

Frédéric Achard , Hugh Eva , Hans‐Jürgen Stibig +4 more

A recently completed research program (TREES) employing the global imaging capabilities of Earth-observing satellites provides updated information on the status of the world's humid tropical forest cover. Between 1990 and … A recently completed research program (TREES) employing the global imaging capabilities of Earth-observing satellites provides updated information on the status of the world's humid tropical forest cover. Between 1990 and 1997, 5.8 ± 1.4 million hectares of humid tropical forest were lost each year, with a further 2.3 ± 0.7 million hectares of forest visibly degraded. These figures indicate that the global net rate of change in forest cover for the humid tropics is 23% lower than the generally accepted rate. This result affects the calculation of carbon fluxes in the global budget and means that the terrestrial sink is smaller than previously inferred.

Nitrogen and Lignin Control of Hardwood Leaf Litter Decomposition Dynamics

1982-06-01

Jerry M. Melillo , John D. Aber , John F. Muratore

The effects of initial nitrogen and lignin contents of six species of hardwood leaves on their decomposition dynamics were studied at the Hubbard Brook Experimental Forest. Rate constants (k) for … The effects of initial nitrogen and lignin contents of six species of hardwood leaves on their decomposition dynamics were studied at the Hubbard Brook Experimental Forest. Rate constants (k) for annual leaf mass loss ranged from —0.08 to —0.47. The rate constants (k) had a negative linear correlation (r2 = .89) with the ratio of initial lignin concentration to initial nitrogen concentration. Decomposition dynamics of the litter materials were described by inverse linear relationships between the percentage of original mass remaining and the nitrogen concentration in the residual material. Initial lignin concentration was highly correlated (r2 = .93) with the slope of the inverse linear relationship for each of the litter types.

Deciduous Forests of Eastern North America

1951-12-01

E. Lucy Braun

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Carbon storage and sequestration by urban trees in the USA

2002-03-01

David J. Nowak , Daniel E. Crane

A DIAGRAMMATIC SCALE FOR ESTIMATING RUST INTENSITY ON LEAVES AND STEMS OF CEREALS

1948-10-01

R. F. Peterson , A. B. Campbell , A. E. Hannah

The Cobb scale and the modified Cobb (U.S.D.A.) scale were devised for estimating, by means of diagrams, the proportion of the area of a leaf or stem occupied by rust … The Cobb scale and the modified Cobb (U.S.D.A.) scale were devised for estimating, by means of diagrams, the proportion of the area of a leaf or stem occupied by rust pustules. Existing diagrams illustrating these scales are inadequate in being arranged in intervals that are too large and irregular, and in not depicting a sufficient range of pustule sizes. New diagrams are presented using smaller regular intervals of rust intensity and a greater range of pustule sizes, thus providing a basis for more objective and accurate determinations.

Improved allometric models to estimate the aboveground biomass of tropical trees

2014-05-10

Jérôme Chave , Maxime Réjou‐Méchain , Alberto Búrquez +7 more

Terrestrial carbon stock mapping is important for the successful implementation of climate change mitigation policies. Its accuracy depends on the availability of reliable allometric models to infer oven-dry aboveground biomass … Terrestrial carbon stock mapping is important for the successful implementation of climate change mitigation policies. Its accuracy depends on the availability of reliable allometric models to infer oven-dry aboveground biomass of trees from census data. The degree of uncertainty associated with previously published pantropical aboveground biomass allometries is large. We analyzed a global database of directly harvested trees at 58 sites, spanning a wide range of climatic conditions and vegetation types (4004 trees ≥ 5 cm trunk diameter). When trunk diameter, total tree height, and wood specific gravity were included in the aboveground biomass model as covariates, a single model was found to hold across tropical vegetation types, with no detectable effect of region or environmental factors. The mean percent bias and variance of this model was only slightly higher than that of locally fitted models. Wood specific gravity was an important predictor of aboveground biomass, especially when including a much broader range of vegetation types than previous studies. The generic tree diameter–height relationship depended linearly on a bioclimatic stress variable E, which compounds indices of temperature variability, precipitation variability, and drought intensity. For cases in which total tree height is unavailable for aboveground biomass estimation, a pantropical model incorporating wood density, trunk diameter, and the variable E outperformed previously published models without height. However, to minimize bias, the development of locally derived diameter–height relationships is advised whenever possible. Both new allometric models should contribute to improve the accuracy of biomass assessment protocols in tropical vegetation types, and to advancing our understanding of architectural and evolutionary constraints on woody plant development.

ECOLOGY OF TROPICAL DRY FOREST

1986-11-01

Peter G. Murphy , A. E. Lugo

widespread, usually transitional between semidesert or savanna and moist forest. About 40% of the earth's tropical and subtropical landmass is dominated by open or closed forest. Of this, 42% is … widespread, usually transitional between semidesert or savanna and moist forest. About 40% of the earth's tropical and subtropical landmass is dominated by open or closed forest. Of this, 42% is dry forest, 33% is moist forest, and only 25% is wet and rain forest (sensu Holdridge, 42; 15). We will never know the true original or potential extent of dry forest because many savannas and scrub or thorn woodlands are thought to be derived from disturbed dry forest. Walter (110), for example, considers most or all of the grassland in India to have been derived from seasonal or dry forest. Some of the processes that cause this conversion are addressed later in this review. The largest proportion of dry forest ecosystems is in Africa and the world's tropical islands, where they account for 70-80% of the forested area. In South America they

Changes in the Carbon Balance of Tropical Forests: Evidence from Long-Term Plots

1998-10-16

Oliver L. Phillips , Yadvinder Malhi , Níro Higuchi +7 more

The role of the world's forests as a "sink" for atmospheric carbon dioxide is the subject of active debate. Long-term monitoring of plots in mature humid tropical forests concentrated in … The role of the world's forests as a "sink" for atmospheric carbon dioxide is the subject of active debate. Long-term monitoring of plots in mature humid tropical forests concentrated in South America revealed that biomass gain by tree growth exceeded losses from tree death in 38 of 50 Neotropical sites. These forest plots have accumulated 0.71 ton, plus or minus 0.34 ton, of carbon per hectare per year in recent decades. The data suggest that Neotropical forests may be a significant carbon sink, reducing the rate of increase in atmospheric carbon dioxide.

Reducing uncertainty in the use of allometric biomass equations for predicting above-ground tree biomass in mixed secondary forests

2001-06-01

Quirine M. Ketterings , Richard Coe , Meine van Noordwijk +2 more

Root biomass allocation in the world's upland forests

1997-06-06

Michael A. Cairns , Sandra Brown , Eileen H. Helmer +1 more

Estimated carbon dioxide emissions from tropical deforestation improved by carbon-density maps

2012-01-27

Alessandro Baccini , S. J. Goetz , Wayne Walker +7 more

Contour-enhanced meta-analysis funnel plots help distinguish publication bias from other causes of asymmetry

2008-06-07

Jaime Peters , Alex J. Sutton , David R. Jones +2 more

BOOSTED TREES FOR ECOLOGICAL MODELING AND PREDICTION

2007-01-01

Glenn De’ath

Accurate prediction and explanation are fundamental objectives of statistical analysis, yet they seldom coincide. Boosted trees are a statistical learning method that attains both of these objectives for regression and … Accurate prediction and explanation are fundamental objectives of statistical analysis, yet they seldom coincide. Boosted trees are a statistical learning method that attains both of these objectives for regression and classification analyses. They can deal with many types of response variables (numeric, categorical, and censored), loss functions (Gaussian, binomial, Poisson, and robust), and predictors (numeric, categorical). Interactions between predictors can also be quantified and visualized. The theory underpinning boosted trees is presented, together with interpretive techniques. A new form of boosted trees, namely, "aggregated boosted trees" (ABT), is proposed and, in a simulation study, is shown to reduce prediction error relative to boosted trees. A regression data set is analyzed using ABT to illustrate the technique and to compare it with other methods, including boosted trees, bagged trees, random forests, and generalized additive models. A software package for ABT analysis using the R software environment is included in the Appendices together with worked examples.

Atlas of United States trees

1971-01-01

Elbert L. Little

magnijica, 8-W Abies procera, 9-W L Overlay 8-^^.Maximum extent of glaeiation in the 'V'^isconsin glacial stage (Pleistocene epoch).Explanation on page 5. (Western United States.) 8 Overlay 8-E. magnijica, 8-W Abies procera, 9-W L Overlay 8-^^.Maximum extent of glaeiation in the 'V'^isconsin glacial stage (Pleistocene epoch).Explanation on page 5. (Western United States.) 8 Overlay 8-E.

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The Storage and Production of Organic Matter in Tropical Forests and Their Role in the Global Carbon Cycle

1982-09-01

Sandra Brown , Ariel E. Lugo

To investigate the storage relationships between and production of organic matter in tropical forests and climate, data on forest biomass, soil organic matter, litter storage, primary production, and litterfall were … To investigate the storage relationships between and production of organic matter in tropical forests and climate, data on forest biomass, soil organic matter, litter storage, primary production, and litterfall were surveyed from the literature and organized using the Holdridge Life Zone system of classification. Ordinary least squares regressions were applied to all the data sets using the ratio of temperature to precipitation (T/P) as an index to climate and the independent variable. Total forest biomass (40-538 t/ha) gave a significant inverted U-shaped relationship with T/P, with peak values in the tropical moist forest life zone and lower ones in wetter and drier forest life zones. Soil carbon content (24-599 t C/ ha) decreased exponentially and significantly with increasing T/P (i.e., from wet to dry forest life zones). No significant relationship was found between litter storage and T/P. Gross primary production (19-120 t/ha yr) decreased curvilinearly and significantly with increasing T/P. Neither net primary production (11-21 t/ha yr) nor wood production (1-11 t/ha yr) were related to T/P. The ratio of leaf litter production to net primary production (0.25-0.65) was inversely related to T/P, suggesting different strategies of allocation of the net primary production in different life zones. The relationship between total litterfall (1.0-15.3 t/ha yr, excluding large wood) and T/P was significant and its shape similar to that obtained for biomass versus T/P; litterfall was highest in tropical moist forest life zones and lower in wetter or drier ones. The linear relationship between biomass and litterfall suggested that the turnover time of biomass in mature tropical forests is similar for all life zones, and is of the order of 34 yr. To determine the role of tropical forests in the global carbon cycle, literature estimates of areas of tropical forests were placed into six life zone groupings. The total tropical and subtropical basal and altitudinal forest area of 1838 million ha was comprised of 42 percent dry forest, 33 percent moist forest, and 25 percent wet and rain forest life zone groups. Organic-matter storage data were also combined into the six life zone groups and the means for each group calculated. The product of forest areas in the six groups and the mean organic matter per unit area in the groups yielded a total storage of 787 billion t organic matter, with vegetation accounting for 58, soils 41, and litter 1 percent. About half of the total storage was located in the tropical basal wet, moist, and dry forest life zone groups. Litterfall data were treated in the same way as organic-matter storage, resulting in a total litter production in tropical forests of 12.3 billion t organic matter/yr. Most litter was produced in the tropical basal moist forest group (30%) and least in the tropical basal dry forest group (10%). Turnover time of litter in tropical forests was less than 1 yr. Lowest turnover times were in very wet (1 yr) and in dry (0.9-1.9 yr) life zone groups. Tropical forests play an important role in the global carbon cycle because they store 46 percent of the world's living terrestrial carbon pool and 11 percent of the world's soil carbon pool.

National-Scale Biomass Estimators for United States Tree Species

2003-02-01

Jennifer C. Jenkins , David C. Chojnacky , Linda S. Heath +1 more

Abstract Estimates of national-scale forest carbon (C) stocks and fluxes are typically based on allometric regression equations developed using dimensional analysis techniques. However, the literature is inconsistent and incomplete with … Abstract Estimates of national-scale forest carbon (C) stocks and fluxes are typically based on allometric regression equations developed using dimensional analysis techniques. However, the literature is inconsistent and incomplete with respect to large-scale forest C estimation. We compiled all available diameter-based allometric regression equations for estimating total aboveground and component biomass, defined in dry weight terms, for trees in the United States. We then implemented a modified meta-analysis based on the published equations to develop a set of consistent, national-scale aboveground biomass regression equations for U.S. species. Equations for predicting biomass of tree components were developed as proportions of total aboveground biomass for hardwood and softwood groups. A comparison with recent equations used to develop large-scale biomass estimates from U.S. forest inventory data for eastern U.S. species suggests general agreement (±30%) between biomass estimates. The comparison also shows that differences in equation forms and species groupings may cause differences at small scales depending on tree size and forest species composition. This analysis represents the first major effort to compile and analyze all available biomass literature in a consistent national-scale framework. The equations developed here are used to compute the biomass estimates used by the model FORCARB to develop the U.S. C budget. FOR. SCI. 49(1):12–35.

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Xylem Structure and the Ascent of Sap

1983-01-01

Martin H. Zimmermann

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Consistent Individualized Feature Attribution for Tree Ensembles

2018-01-01

Scott Lundberg , Gabriel Erion , Su‐In Lee

Interpreting predictions from tree ensemble methods such as gradient boosting machines and random forests is important, yet feature attribution for trees is often heuristic and not individualized for each prediction. … Interpreting predictions from tree ensemble methods such as gradient boosting machines and random forests is important, yet feature attribution for trees is often heuristic and not individualized for each prediction. Here we show that popular feature attribution methods are inconsistent, meaning they can lower a feature's assigned importance when the true impact of that feature actually increases. This is a fundamental problem that casts doubt on any comparison between features. To address it we turn to recent applications of game theory and develop fast exact tree solutions for SHAP (SHapley Additive exPlanation) values, which are the unique consistent and locally accurate attribution values. We then extend SHAP values to interaction effects and define SHAP interaction values. We propose a rich visualization of individualized feature attributions that improves over classic attribution summaries and partial dependence plots, and a unique "supervised" clustering (clustering based on feature attributions). We demonstrate better agreement with human intuition through a user study, exponential improvements in run time, improved clustering performance, and better identification of influential features. An implementation of our algorithm has also been merged into XGBoost and LightGBM, see http://github.com/slundberg/shap for details.

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Biomass Estimation Methods for Tropical Forests with Applications to Forest Inventory Data

1989-12-01

Sandra Brown , Andrew Gillespie , Ariel E. Lugo

Abstract This paper contains a strategy for estimating total aboveground biomass of tropical forests. We developed regression equations to estimate aboveground biomass of individual trees as a function of diameter … Abstract This paper contains a strategy for estimating total aboveground biomass of tropical forests. We developed regression equations to estimate aboveground biomass of individual trees as a function of diameter at breast height, total height, wood density, and Holdridge life zone (sensu Holdridge 1967). The regressions are applied to some 5,300 trees from 43 independent sample plots, and 101 stand tables from large-scale forest inventories in four countries, to estimate commercial and total aboveground biomass per unit area by forest type, and to estimate expansion factors defined as the ratio of aboveground to commercial biomass. The quadratic stand diameter (QSD, i.e., the diameter of a tree of average basal area) in a given forest stand influences the magnitude of the expansion factor. Stands of small trees have large expansion factors (up to 6.4), and as QSD increases, the expansion factor decreases to a constant value (about 1.75). For undisturbed forests in moist, moist transition to dry, and dry life zones respectively, the expansion factors for total aboveground biomass were 1.74, 1.95, and 1.57 respectively. For undisturbed, logged, and nonproductive forest categories used by the FAO to report global commercial wood volume data, we estimated expansion factors of 1.75, 1.90, and 2.00 respectively. Applying these factors to FAO data results in a 28 to 47% increase in previous volume-derived estimates of tropical forest biomass. However, estimates of tropical forest biomass based on small destructive samples continue to be high relative to estimates based on volume data. For. Sci. 35(4):881-902.

Minimal legacy effects of metal pollution on litter decomposition and soil respiration following liming and tree planting

2025-06-25

Patrick A. Levasseur , Nathan Basiliko , Emily Smenderovac +1 more | The Science of The Total Environment

Modelling Pinus pinaster Ait. resin yield using a "divide and conquer" approach and machine learning

2025-06-25

Óscar López-Álvarez , Luis Franco-Vázquez , Manuel Francisco Marey Pérez | Industrial Crops and Products

Growth performance of Eucalyptus camaldulensis across two distinct sites in Sindhuli district of Nepal

2025-06-25

Sima Lamichhane , Ram Chandra Bhusal , Yam Bahadur K.C. | Archives of Agriculture and Environmental Science

This study evaluated the site-specific growth performance of Eucalyptus camaldulensis plantations in Nepal’s Sindhuli district, comparing -terraced agricultural land (Site 1) and flatland (Site 2) over nine years. The aim … This study evaluated the site-specific growth performance of Eucalyptus camaldulensis plantations in Nepal’s Sindhuli district, comparing -terraced agricultural land (Site 1) and flatland (Site 2) over nine years. The aim was to quantify differences in growth parameters and soil properties to perform sustainable plantation management. Diameter at breast height (DBH), height, basal area, volume, and above-ground total biomass (AGTB) were measured for 314 trees, alongside soil nutrients analysis (pH, organic carbon, N, P, K) from 43 plots. Statistical analyses (Welch’s t-test, regression) were employed to assess site variations. Results revealed significantly (p < 0.001) superior growth in Site 2, with higher mean DBH (9.00 ± 2.61 cm vs. 6.95 ± 3.71 cm), height (7.88 ± 0.80 m vs. 7.01 ± 1.97 m), and AGTB (26.96 ± 17.11 kg vs. 20.48 ± 34.16 kg) compared to Site 1. Volume distribution also significantly (p < 0.001) favored at Site 2 across all diameter classes (e.g., >15 cm: 0.16 m³ vs. 0.12 m³). Soil pH was significantly lower in Site 2 (4.72 vs. 5.48, p < 0.05), likely due to Eucalyptus litter acidity, though other nutrients remained comparable. Regression confirmed DBH and height as robust predictors of volume (R² = 0.955). The findings highlighted the flatland topography as optimal for E. camaldulensis productivity, driven by favorable microclimatic and edaphic conditions. Therefore, this study recommends strategic site selection prioritizing flatlands and pH-adjusted soil management to enhance carbon sequestration and timber yields, offering actionable insights for agroforestry resilience in Nepal’s mid-hills.

Tracking Floristic Diversity in Cantabrian Mixed Forests

2025-06-24

Eduardo Cires , Mauro Sanna , Luz María Madrazo-Frías +5 more | Conservation

Cantabrian mixed forests, located in areas of Spain, Portugal, and France, serve as an essential biogeographic transition region, noted for its extraordinary plant diversity and ecological intricacy. To aid conservation … Cantabrian mixed forests, located in areas of Spain, Portugal, and France, serve as an essential biogeographic transition region, noted for its extraordinary plant diversity and ecological intricacy. To aid conservation and research initiatives, a uniform checklist of vascular plants was created, incorporating information from citizen science platforms, scientific databases, herbarium records, and local floras. The outcome is a carefully selected collection of more than 8000 taxa, with over 76% recognized as native, highlighting the area’s importance as a reservoir of biodiversity and a climate refuge. Taxonomic discrepancies were resolved via expert verification and adherence to international naming standards, establishing a dependable basis for ecological research. The checklist demonstrates notable variations in organisms, ecological approaches, and evolutionary lineages, influenced by geographical diversity, climate variations, and past land use patterns. Importantly, the study emphasizes the drawbacks of unchecked biodiversity data and shows the benefits of expert-driven synthesis for addressing gaps and biases in species documentation. The floristic information presented here can act as a basis for transboundary conservation planning, ongoing biodiversity tracking, and the development of adaptive management approaches in response to climate change and ecological decline. This initiative represents an important move towards safeguarding the distinct natural heritage of this distinctive biogeographic region.

Enrichment planting to restore secondary forests in Central Amazon: A perspective on timber production and carbon sequestration

2025-06-24

Guilherme Silva Modolo , Thalita Vitória Mamede Silva , Victor Alexandre Hardt Ferreira dos Santos +5 more | Forest Ecology and Management

Improved allometry and heartwood development of Sequoia sempervirens in secondary forests

2025-06-24

Stephen C. Sillett , Alana R. O. Chin , Allyson L. Carroll +2 more | Forest Ecology and Management

Effects of the Light-Felling Intensity on Hydrological Processes in a Korean Pine (Pinus koraiensis) Forest on Changbai Mountain in China

2025-06-24

Qian Liu , Zhenzhao Zhou , Xiaoyang Li +6 more | Forests

(1) Background: Understanding how forest management practices regulate hydrological cycles is critical for sustainable water resource management and addressing global water crises. However, the effects of light-felling (selective thinning) on … (1) Background: Understanding how forest management practices regulate hydrological cycles is critical for sustainable water resource management and addressing global water crises. However, the effects of light-felling (selective thinning) on hydrological processes in temperate mixed forests remain poorly understood. This study comprehensively evaluated the impacts of light-felling intensity levels on three hydrological layers (canopy, litter, and soil) in mid-rotation Korean pine (Pinus koraiensis) forests managed under the “planting conifer and preserving broadleaved trees” (PCPBT) system on Changbai Mountain, China. (2) Methods: Hydrological processes—including canopy interception, throughfall, stemflow, litter interception, soil water absorption, runoff, and evapotranspiration—were measured across five light-felling intensity levels (control, low, medium, heavy, and clear-cutting) during the growing season. The stand structure and precipitation characteristics were analyzed to elucidate the driving mechanisms. (3) Results: (1) Low and heavy light-felling significantly increased the canopy interception by 18.9%~57.0% (p < 0.05), while medium-intensity light-felling reduced it by 20.6%. The throughfall was significantly decreased 10.7% at low intensity but increased 5.3% at medium intensity. The stemflow rates declined by 15.8%~42.7% across all treatments. (2) The litter interception was reduced by 22.1% under heavy-intensity light-felling (p < 0.05). (3) The soil runoff rates decreased by 56.3%, 16.1%, and 6.5% under the low, heavy, and clear-cutting intensity levels, respectively, although increased by 27.1% under medium-intensity activity (p < 0.05). (4) The monthly hydrological dynamics shifted from bimodal (control) to unimodal patterns under most treatments. (5) The canopy processes were primarily driven by precipitation, while litter interception was influenced by throughfall and tree diversity. The soil processes correlated strongly with throughfall. (4) Conclusions: Low and heavy light-felling led to enhanced canopy interception and reduced soil runoff and mitigated flood risks, whereas medium-intensity light-felling supports water supply during droughts by increasing the throughfall and runoff. These findings provide critical insights for balancing carbon sequestration and hydrological regulation in forest management.

Delineating treeline dynamics and its impact on carbon storage in Alpine region of Nepal

2025-06-23

Badri Bhattarai , Mahendra Singh Thapa , Sandesh Gharti +7 more | Research Square (Research Square)

<title>Abstract</title> Alpine treeline dynamics significantly influence biodiversity and global carbon cycles, yet their responses to climate change and implications for carbon storage remain under studied in the Himalayas. This research … <title>Abstract</title> Alpine treeline dynamics significantly influence biodiversity and global carbon cycles, yet their responses to climate change and implications for carbon storage remain under studied in the Himalayas. This research work focuses on delineating the treeline elevation shifts (1993–2023) and their impact on above-ground carbon stocks in Rolwaling Valley, Nepal, using Local Indicator of Spatial Association (LISA) autocorrelation, and stratified random sampling across 100-m elevation strata. Results showed minimal upward treeline migration (4.56m over 30 years), with average elevation stabilizing at treeline3961.49 ± 18.30 by 2023. The slight upward trend in the NDVI (0.0011 units/year) indicates improved vegetation density over the 30 years in the study area. Above-ground carbon stocks declined significantly with elevation, ranging from 48.33 Mg/ha (3700-3800m) to 40.52 Mg/ha (3900-4000m), equivalent to a loss of 67.84 kg per meter gained. Analytical Hierarchy Process (AHP) prioritization identified forest restoration and silviculture interventions as the most effective measures for enhancing carbon benefits. The study provides actionable insights for aligning ecosystem management in alpine areas with Sustainable Development Goal (SDG) -13 (Climate Action) and 15 (Life on Land), with a focus on adaptive strategies to enhance carbon sinks in alpine’s warming climate.

Efectividad y límites de la independencia de escala en las huellas deposicionales de un abanico aluvial experimental

2025-06-23

Rudolf Florin , Bruno Mazzorana , Ivan Javier Rojas Castillo +1 more | Cuaternario y Geomorfología

Los abanicos aluviales constituyen entornos atractivos para el desarrollo de asentamientos humanos en zonas montañosas, no obstante, su evolución dinámica conlleva un importante riesgo para la población e infraestructura aledaña. … Los abanicos aluviales constituyen entornos atractivos para el desarrollo de asentamientos humanos en zonas montañosas, no obstante, su evolución dinámica conlleva un importante riesgo para la población e infraestructura aledaña. En las últimas décadas ha habido un notable desarrollo en el estudio de estas formas de terreno desde un enfoque experimental, sin embargo, existen limitaciones fundamentales al aplicar los principios del escalamiento clásico para representar estos sistemas. Por lo tanto, es necesario evaluar cuán capaces son los modelos de capturar la dinámica de los paisajes naturales y avanzar hacia una comprensión cuantitativa sobre la efectividad y límites de la independencia de escala natural en la morfodinámica. Para ello realizamos una serie de lanzamientos experimentales con flujos cargados de sedimentos en un modelo físico de abanico aluvial replicado en dos escalas diferentes (1:1 y 3:4). Las áreas de exposición asociadas a cada experimento se cuantificaron y mapearon en SIG. Luego, para evaluar el grado de similitud estadística de los patrones al variar la escala del modelo se generaron mapas de probabilidad de exposición, análisis estadístico descriptivo e inferencial de los porcentajes de exposición y análisis estadístico espacial de la distribución de la probabilidad de exposición. Los resultados obtenidos evidenciaron variaciones estadísticas significativas en la dinámica distributiva de ambos modelos, reflejando una disimilitud en la cinemática de los procesos que ocurren en el abanico, lo cual lleva a concluir que, al menos para un modelo bajo condiciones de flujo no confinado similar al utilizado en este estudio, la independencia de escala no aplica totalmente. Esto implica que los modelos a escala reducida deben utilizarse con precaución, especialmente para el estudio de riesgos en abanicos reales, ya que la respuesta en términos estadísticos sobre la indicación del peligro presenta discrepancias significativas al variar la escala del modelo utilizado.

Assessment of Stand Structure, Composition and Diversity of Woody Flora in the Biodiversity Heritage Site (BHS) of GKVK, UAS, Bengaluru

2025-06-23

K. Vasundhara , R. K. Murthy , A. S. Devakumar +4 more | Journal of Advances in Biology & Biotechnology

An inventory study was conducted to quantify the stand structure, composition and diversity of the woody plants in the Biodiversity Heritage Site of GKVK, UAS, Bengaluru. It is divided into … An inventory study was conducted to quantify the stand structure, composition and diversity of the woody plants in the Biodiversity Heritage Site of GKVK, UAS, Bengaluru. It is divided into three patches and further divided into 14 areas. Random quadrat sampling was used to assess the parameters. A total of 96 species belonging to 27 families were documented. Fabaceae was the most dominant family covering a total of 32 tree species. The diversity indices of the study area were 3.32, 0.93 and 0.73 for Shannon-Wiener index (H'), Simpson diversity index (1-D) and Evenness index (J') respectively. Area E4 and C showed 39% of similarity of tree species according to Jaccard’s similarity index. Stand density and basal area of the study area was 356 stems ha–1 and 20.58 m2 ha–1 respectively. Mangifera indica was dominant species among all the tree species in the study area with an IVI value of 56.57 and with a density of 47.54 stems ha–1. Girth class distribution showed inverse J shape pattern for all three patches and even for the entire study area. Botanical Garden (Area D) showed greater diversity with better distribution of species, stem density and with good population structure (reverse J shape) and composition with a greater number of individuals at higher girth classes compared to the other patches.

A Generalized Marginal and Mixed-Effect Models for Predicting Tree-Level Mortality with Unequal Measurement Intervals for Scots Pine in Finland

2025-06-23

Jouni Siipilehto , Harri Mäkinen | Forest Science

Abstract Logistic regression has been used to model individual tree mortality. However, unequal measurement intervals limit the use of reasonable link functions. Although marginal and mixed-effects models have been used, … Abstract Logistic regression has been used to model individual tree mortality. However, unequal measurement intervals limit the use of reasonable link functions. Although marginal and mixed-effects models have been used, a comparison of these models for predicting mortality in new stands is lacking. We developed models for predicting the mortality of Scots pine ( Pinus sylvestris ) trees in Finland. The modelling data comprised 44 thinning experiments (127,057 tree-level observations), and 50% of the experiments were randomly selected for model evaluation (43 experiments, 112,518 tree-level observations). A complementary log–log model was used to predict mortality probability based on tree and stand characteristics and thinning effects. The measurement period length was added as an offset variable. The marginal (population-average) and mixed models with random effects (site, plot, and year) were fitted and evaluated. The evaluation consisted of fit statistics, comparisons of predicted and observed mortality rates, and simulations using the Motti stand simulator. The mixed models clearly provided better statistical fits than the marginal model. The evaluation with the Motti simulator showed the most accurate prediction in terms of stem number ( N ) and stand basal area ( G ) when using the marginal model. All models, except the random year effect, resulted in maximum G values that remained at a reasonable level in the prolonged Motti simulations. The current survival model in the Motti simulator is based on a relative density index derived from the self-thinning line and provides good prediction accuracy. Based on the new BAL -based models, we recommend the marginal model as an option to the current model.

Evaluating individual tree metrics calculated from unmanned aerial vehicle laser scanning as input to a conventional growth and yield model

2025-06-23

Matthew J. Sumnall , David R. Carter , Timothy J. Albaugh +3 more | International Journal of Remote Sensing

Enhanced aboveground biomass density estimation in Central Vietnamese forests

2025-06-23

Viet Hoang Ho , Hidenori MORITA , Felix Bachofer +1 more | Ecological Modelling

Variation in soil physico-chemical properties and species composition across the altitudinal gradient in different forests of Uttarakhand, India

2025-06-23

Naveen Pandey , Geetanjali Upadhyay , Sheetal Koranga +5 more | Environmental Monitoring and Assessment

Effects of a three-year warming on the growth and nutritional status of the young generation of silver fir (Abies alba Mill.) in the Western Carpathians

2025-06-23

Dawid Kupka , Daryna Pasichnyk , Kaiwen Pan +1 more | Forest Ecology and Management

Linking understory functional traits to soil organic carbon storage in natural and planted subtropical forests

2025-06-23

Cristhian dos Santos Teixeira , Marcelo Malysz , Elivane Salete Capellesso +2 more | Journal of Environmental Management

Genetic variation and selection of half-sib families of Pinus sibirica in the Xinlin district of the Greater Khingan Range

2025-06-21

Xudong Li , Guijie Han , Yujun Zhou +6 more | Journal of Forestry Research

Abstract To investigate the genetic variation patterns of multiple traits in Pinus sibirica half_sibling families introduced to the Greater Khingan Range, this study aims to establish a comprehensive trait evaluation … Abstract To investigate the genetic variation patterns of multiple traits in Pinus sibirica half_sibling families introduced to the Greater Khingan Range, this study aims to establish a comprehensive trait evaluation system based on genetic parameters and identify fast-growing, high-quality genetic materials. The findings provide scientific support for advanced-generation seed orchard development and multi-objective genetic improvement. A total of 66 half-sibling families from a 26-year-old trial plantation of the Tomsk seed source were evaluated. Eleven traits were measured, including growth traits (tree height, diameter at breast height, volume, and crown width), morphological traits (lateral branch diameter), wood quality traits (Pilodyn value), and needle traits (fresh weight, dry weight, moisture content, needle length, and needle width). Genetic parameters were estimated using variance component decomposition. Superior families with favorable performance in both growth and wood density traits were identified using Best Linear Unbiased Prediction (BLUP) weighted by genetic correlation coefficients. Additionally, individual tree selection was conducted based on growth traits using the index selection method. Significant genetic differences among families (Z ratio > 1.50) were observed for 10 traits, including growth, wood density, and needle traits. The phenotypic coefficient of variation (PCV: 5.05–62.50%) and genetic coefficient of variation (GCV: 2.19–13.81%) exhibited substantial heterogeneity. Volume displayed the highest variation (PCV = 62.50%, GCV = 13.81%), while the highest family heritability was observed for the needle length-to-width ratio ( h 2 = 78.30%), and the highest individual heritability was recorded for needle moisture content ( H 2 = 95.22%). Genetic correlations analysis revealed strong positive associations between volume and tree height ( r = 0.880), diameter at breast height ( r = 0.968), and Pilodyn value ( r = 0.508). Using the BLUP method, 13 superior families (e.g., Families 59, 11, and 51) were identified, with an average genetic gain in volume of 13.377% and a family retention rate of 70%, significantly exceeding the population mean (65.10%). Through index selection, 94 elite individual trees were selected, 52.14% of which originated from superior families. The genetic gain in individual tree volume reached 26.80%, with the within-family gain for elite individuals increasing to 28.47%. This study establishes the first multi-trait genetic evaluation model for P. sibirica and proposes a “family-individual” collaborative selection strategy. The selected superior families achieved a volume genetic gain of 3.864–32.307% and an overall genetic gain of 2.729–20.069%, while elite individual trees exhibited a volume genetic gain of 16.328–52.716%. These findings would provide critical technical support for multi-objective breeding and seed orchard development in cold-temperate coniferous species. Graphic abstract

Beyond bark thickness: multifunctional explanations for variations in relative bark allocation in temperate forest trees

2025-06-21

Huabin Zhao , Zhanwei Liu , Bob Yi-Chen Duan +5 more | Journal of Forestry Research

Modelling the impacts of climate change and harvesting on carbon dynamics in representative subtropical secondary forests: A case study from Hunan Province, China

2025-06-20

Longjun Wang , Haoyun Liu , Zelin Liu +7 more | Ecological Modelling

Impact of Short-Term and Prolonged (Multi-Year) Droughts on Tree Mortality at the Individual Tree and Stand Levels

2025-06-20

Goran Češljar , Zvonimir Baković , Ilija Djordjević +4 more | Plants

Droughts accompanied by high temperatures are becoming increasingly frequent across Europe and globally. Both individual trees and entire forest ecosystems are exposed to drought stress, with prolonged drought periods leading … Droughts accompanied by high temperatures are becoming increasingly frequent across Europe and globally. Both individual trees and entire forest ecosystems are exposed to drought stress, with prolonged drought periods leading to increased tree mortality. Therefore, continuous monitoring, data collection, and analysis of tree mortality are essential prerequisites for understanding the complex interactions between climate and trees. This study examined the effects of short-term and prolonged (multi-year) droughts on the mortality of individual trees and forests in Serbia. The analysis was based on datasets from our previous research on the influence of drought and drought duration on individual tree mortality in Serbian forest ecosystems, supplemented with new data collected through the International Co-operative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests). Additionally, we incorporated data from the public enterprise (PE) “Srbijašume”, which manages forests in Central Serbia, focusing on random yields resulting from natural disasters (droughts). These data enabled a comparative assessment of the findings on increased mortality and drought impact at both the individual tree level and the stand level. This study identifies key similarities and differences in tree mortality trends based on drought duration and examines their correlations within the same time frame (2004–2023). By analysing climatic conditions across Serbia, we provide evidence of the interaction between drought periods and increased forest mortality, which we further confirmed by calculating the Standardized Precipitation Evapotranspiration Index (SPEI). We also address the tree species that were most sensitive to the effects of drought. Our findings indicate that prolonged (multi-year) droughts, accompanied by high temperatures, have significantly contributed to increased tree mortality over the past decade. Successive multi-year droughts pose a substantial threat to both individual trees and entire forests, producing more severe and persistent responses compared to those caused by single-year droughts, which forests and individual trees are generally more capable of tolerating. Moreover, due to prolonged drought stress, trees weaken, leading to delayed mortality that may manifest several years after the initial drought event. The observed increase in tree mortality has been found to correlate with rising temperatures and the growing frequency of prolonged droughts over the past decade. Especially, intense droughts in the growing season (April–September) have a very negative impact on forests.

The effects of stand spatial structure on the aboveground biomass allocation in Chinese fir (Cunninghamia lanceolata) plantations

2025-06-19

Xiang Huang , Yao Zhang , Jianwei Geng +6 more | Frontiers in Plant Science

Introduction Chinese fir ( Cunninghamia lanceolata ) is the fastest-growing timber species in China. investigating its spatial structure and influence on aboveground biomass allocation is crucial for understanding its adaptability … Introduction Chinese fir ( Cunninghamia lanceolata ) is the fastest-growing timber species in China. investigating its spatial structure and influence on aboveground biomass allocation is crucial for understanding its adaptability to environmental conditions, enhancing carbon sequestration, and maintaining forest ecosystem stability. Methods In this study, airborne LiDAR technology was used to derive forest structural metrics, and weighted Voronoi diagrams were constructed to extract spatial configuration metrics. Biomass models for different components of Chinese fir were developed using 20 harvested trees, and stem mass fraction (SMF), branch mass fraction (BMF), and leaf mass fraction (FMF) were calculated. Path analysis quantified the effects of stand structure variables on biomass allocation among different organs. Results The openness ratio (OP), angle competition index (UCI), forest layer index (S), and openness (K) were identified as the primary spatial structural factors influencing aboveground biomass allocation. Stem biomass accumulation is maximized when 0.75 &lt; OP ≤ 1, 0 &lt; UCI ≤ 0.25, 0 &lt; S ≤ 0.25, and 0.4 &lt; K ≤ 0.5, with SMF reaching its highest value. Branch biomass peaks when 0.5 &lt; OP ≤ 0.75, 0 &lt; UCI ≤ 0.25, 0.75 &lt; S ≤ 1, and 0.4 &lt; K ≤ 0.5, maximizing BMF. Leaf biomass is highest when 0 &lt; OP ≤ 0.25, 0.5 &lt; UCI ≤ 0.75, 0.5 &lt; S ≤ 0.75, and 0.2 &lt; K ≤ 0.3, leading to the maximum FMF. Discussion The results of this study not only reveal the survival strategy of Chinese fir in environmental change, but also provide a theoretical basis for understanding ecosystem carbon sequestration and sustainable management of Chinese fir plantations.

Impacts on the health of large trees in Brazilian semi-deciduous seasonal forest

2025-06-19

Joana Vieira , J. P. Araújo , José Marcelo Domingues Torezan | Forest Ecology and Management

Pamber Forest

2025-06-19

C.J. Barnett , Petra Dark , Julie Dunne +7 more | Oxbow Books

Integrating rainfall data into site-specific modelling to improve forest productivity estimation of eucalypt hybrid species in coastal Zululand, South Africa

2025-06-19

Morries Chauke , Henry Mwambi , Antônio Carlos Ferraz Filho | Southern Forests a Journal of Forest Science

Evaluating the Wood Quality of Conifer Species in the Greek Forest Sector Using an Integrated Multi-Criteria Decision Analysis (MCDA) Approach

2025-06-19

Marina Chavenetidou , Stefanos Tsiaras , Panagiotis P. Koulelis +1 more | Forests

The aim of this study was to evaluate the suitability of eight softwood species most commonly used by Greek timber industries, including furniture manufacturers and companies producing roundwood, sawn timber, … The aim of this study was to evaluate the suitability of eight softwood species most commonly used by Greek timber industries, including furniture manufacturers and companies producing roundwood, sawn timber, and plywood. The analysis was based on integrated Multi-Criteria Decision Analysis (MCDA), using a combined approach of the PROMETHEE method and the Analytical Hierarchy Process (AHP), taking into consideration some important criteria that affect timber quality. According to the PROMETHEE complete ranking, Aleppo pine (Pinus halepensis Mill.) achieved the best performance under the selected criteria among the examined softwood species, underlying the importance of Aleppo pine to the Greek timber industry. Our findings could be highly beneficial to the wood industry, promoting the recovery and advancement of the forest sector in general, taking into account that sustainable wood supply is lower than the total biomass available in Europe. Policymakers should prioritize the selection of conifer tree species that can strengthen Greece’s forestry sector, promote sustainable management practices, and increase the economic value derived from the country’s diverse forest resources.

Development of a height-diameter model for New Zealandgrown tōtara (Podocarpus totara G. Benn. ex D. Don)

2025-06-19

Serajis Salekin , Christian Roschak , Greg Steward | New Zealand journal of forestry science

Background: Robust species-specific height-diameter (H-D) equations are necessary for the estimation and prediction of tree volume, yield, biomass or carbon stocks. In addition, information about height growth characteristics allows for … Background: Robust species-specific height-diameter (H-D) equations are necessary for the estimation and prediction of tree volume, yield, biomass or carbon stocks. In addition, information about height growth characteristics allows for the analysis of stand growth dynamics. But there is a general lack of species-specific growth models for most New Zealand native tree species considered for plantation and wood production. Therefore, the aim of this study was to develop a species- and site-specific H-D model for planted lowland tōtara (Podocarpus totara G. Benn. ex D. Don). Methods: The models were developed using data from 719 individually measured trees aged 11 to 110 years from eight different sites in the North Island of New Zealand. Two different modelling approaches, traditional non-linear and linear mixed effect, were used. The process included selecting, testing, conditioning, and extending a total of 18 different equations by incorporating site-specific tree variables. Results: The most precise model predicting the H-D relationship was reported by linear mixed-effect models that include diameter at breast height (DBH at 1.4 m, cm) and age (years). The final model had a low root mean square error (RMSE, 0.21, m), mean absolute error (MAE, 0.16, m) and high R2 (0.94), which slightly increased during validation. Conclusions: The study demonstrated a robust process and reported the most plausible and parsimonious model to predict P. totara’s H-D relationship, which serves as the basis for species-specific growth dynamics. The reported models provide for the first time the opportunity to predict the H-D relationship of planted P. totara in New Zealand. This fills a long existing knowledge gap and provides forest growers and managers important decision-making information.

Restoration of riparian forest cover increases carbon stocks in the Pacific Northwest

2025-06-18

Regina O’Kelley , Rose A. Graves , Holly Amer +1 more | Environmental Research Letters

Abstract Reforestation of degraded riparian areas provides climate mitigation benefits through increased carbon (C) storage. However, the magnitude of this potential natural climate solution remains uncertain across ecoregions. Few studies … Abstract Reforestation of degraded riparian areas provides climate mitigation benefits through increased carbon (C) storage. However, the magnitude of this potential natural climate solution remains uncertain across ecoregions. Few studies have evaluated riparian planting C sequestration and storage, particularly in highly productive wet riparian ecosystems. In recent decades, riparian reforestation has accelerated in the Pacific Northwest (PNW) of the United States, primarily aiming to restore ecosystem functions and associated benefits.&#xD;Using these plantings as a ‘natural experiment’, we assessed C storage in woody vegetation (trees and shrubs) and soils across a chronosequence of PNW riparian reforestation sites. Our study evaluated changes in C storage with planting age and identified key covariates affecting C storage in plants and soils and their relationship with planting age across a ~430 km latitudinal gradient in western Oregon, USA.&#xD;We found that woody and soil C stocks increase with planting age, averaging 24% and 1% per year, respectively. Increases in tree C were strongly driven by increasing planting age and tree stem density. Understory C was weakly related to stand characteristics and geomorphic properties, and strongly related to planting age. Soil C gains were positively driven by precipitation. We find that riparian reforestation can result in increased C storage, with woody vegetation comprising most of the increase. Our results highlight the importance of including both trees and shrubs in plantings to realize C accumulation gains in the earlier years. Because C accumulation is gradual, yet compounding (i.e., 10+ and 15+ years for total C stocks to increase by 1.95, and 19.2 Mg C ha-1, respectively), riparian reforestation projects implemented today could take over a decade to deliver high natural climate solution benefits, emphasizing the urgency to implement these projects to limit the worst of climate change impacts.&#xD;

Influence of environmental factors on the survival and growth of Eucalyptus tereticornis provenances in the Brazilian semi-arid

2025-06-18

Ângela Torquato Loiola , Ewerton Souto Pinheiro , Ana Ruth da Silva Souza +3 more | Forest Ecology and Management

Calibration of the FullCAM model for Australian native vegetation

2025-06-17

David I. Forrester , Jacqueline R. England , Chiara Pasut +7 more | Ecological Modelling

Forest type, landowner practices, and climate shape tree species diversity in Maine, USA

2025-06-17

Jianheng Zhao , Adam Daigneault , Xinyuan Wei +2 more | Forest Ecology and Management

Does pruning affect the structural and ecological productivity of Juniper woodlands in the eastern Hindu Kush?

2025-06-17

Ndongo Din , Nasrullah Khan , Rafi Ullah +5 more | PeerJ

Juniperus species play a crucial role in the ecological dynamics of the eastern Hindu Kush region in Pakistan, growing either as mono-specific stands or co-occurring in species-poor communities on mountainous … Juniperus species play a crucial role in the ecological dynamics of the eastern Hindu Kush region in Pakistan, growing either as mono-specific stands or co-occurring in species-poor communities on mountainous scree slopes, as well as near agricultural and residential areas. Despite their limited population, these trees offer a diverse range of ecosystem services, emphasizing the intricate interdependence between human and natural ecosystems. Given their ecological and commercial importance, local people employ silvicultural practices, such as pruning, to ensure sustainable management. The present study, therefore, aimed to assess conventional pruning practices in the region to understand their impacts on stand structure and ecological productivity. The findings indicated that pruning at an intensity of 30-40% was particularly effective, significantly enhancing dendrometric and reproductive traits, such as height, growth rates, and the production of viable seeds (ANOVA, p < 0.05). Additionally, both diameter at breast height (DBH) and diameter at root collar (DRC) showed positive trends, although the effects were not statistically significant (ANOVA, p > 0.05). Conversely, pruning intensities exceeding 60% exhibited adverse effects on the tree metrics. Our results also highlight the importance of pruning intensities in regulating understory vegetation, soil nutrient dynamics, and the carbon storage capacity of junipers. Notably, moderate pruning demonstrates positive impacts on living carbon biomass (LCB) and on soil organic carbon (SOC) density. In conclusion, adopting moderate-intensity pruning techniques with standard scientific measures could be an effective strategy, not only for improving the structural parameters and carbon budgets amid changing climate conditions but also for ensuring long-term economic advantages in the region.

Wood Anatomy Properties and Global Climate Change Constraints of Forest Species from the Natural Forest of Mozambique

2025-06-17

Eugénia Joaquim-Meque , José Louzada , Francisco Tarcísio Moraes Mady +3 more | Forests

Mozambique’s natural forests are increasingly affected by climate change, deforestation, and unsustainable exploitation, threatening both biodiversity and rural livelihoods. This study examines the wood anatomical characteristics of five commercially important … Mozambique’s natural forests are increasingly affected by climate change, deforestation, and unsustainable exploitation, threatening both biodiversity and rural livelihoods. This study examines the wood anatomical characteristics of five commercially important tree species—Spirostachys africana Sond., Afzelia quanzensis Welw., Millettia stuhlmannii Taub., Pterocarpus angolensis DC., and Colophospermum mopane (J. Kirk ex Benth.) J. Léonard—to assess their vulnerability to drought, cyclones, and floods. The aim is to enhance current knowledge regarding their wood anatomy and to clarify how these anatomical traits could help to identify species most vulnerable to climate extremes. Wood samples were collected from native forests and analyzed in laboratories in Brazil and Portugal using standardized anatomical methods according to IAWA guidelines. The results show that Afzelia quanzensis, Millettia stuhlmannii, Pterocarpus angolensis, and Colophospermum mopane have solitary vessels with vestured pits and thick-walled fibers, which improve hydraulic conductivity and drought resistance. Colophospermum mopane shows the greatest anatomical adaptation to climatic stressors. By contrast, Spirostachys africana has narrow, grouped vessels and thin walls, indicating higher susceptibility to embolism and limited resilience. Cyclone resistance is associated with higher wood density and parenchyma abundance, which enhance mechanical stability and recovery. Flood resilience, however, appears to depend more on leaf and root adaptations than on wood anatomy alone. These findings highlight the role of wood structure in climate adaptability and underline the urgency of integrating anatomical data into forest management strategies to support the conservation and sustainable use of Mozambique’s forest resources.

A decade-long study on mortality in European larch (Larix decidua Mill.), Japanese larch (Larix kaempferi (Lamb.) Car.) and their hybrid

2025-06-17

Naincy Sagar , Luc Pâques , Stéphane Chantepie | Annals of Forest Science

Monitoring the Forest Cover of the Chiang Mai Area in Thailand

2025-06-17

Adithya Valivety , Bhanu Harsha Vardhan Nandamuri , N. V. B. S. S. Karthikeya +1 more | Auerbach Publications eBooks

Analysis of the fluctuations of main water balance components at six forest stands in the Great Hungarian Plain

2025-06-16

Bence Bolla , Ján Szolgay , Zoltán Gribovszki +3 more | Acta hydrologica Slovaca

Mixed-effect modelling of Tectona grandis L.f. yield at stand-level

2025-06-16

Lucas Araujo Moura , Allan Libanio Pelissari , Luan Demarco Fiorentin +3 more | Southern Forests a Journal of Forest Science

Study on tree diversity, community utilization categories and soil carbon stock in alder-based jhum farming and community forest of Khonoma Village, Nagaland

2025-06-16

Meribeni Tsopoe , Kambam Boxen Meetei , Rupjyoti C. Baruah +2 more | Vegetos

Impact of different levels of water deficit on physiological and fluorescence responses in Eucalyptus urophylla × E. grandis

2025-06-16

Marcello Zatta Péres , José Eduardo Macedo Pezzopane , Gilson Fernandes da Silva +5 more | Canadian Journal of Forest Research

This study evaluated the physiological responses of Eucalyptus urophylla × E. grandis under varying water stress levels and their recovery post-rehydration. Plants were exposed to control, light (LS), and moderate … This study evaluated the physiological responses of Eucalyptus urophylla × E. grandis under varying water stress levels and their recovery post-rehydration. Plants were exposed to control, light (LS), and moderate (MS) water stress treatments in an open area, with continuous monitoring of meteorological conditions. Physiological parameters, including net photosynthesis, stomatal conductance, transpiration, and the Crop Water Stress Index (CWSI), were assessed. Mini-lysimeters measured cumulative plant transpiration. Results showed that predawn leaf water potential (Ψpd) declined by approximately 196% under LS and 599% under MS compared to the control (-0.2), reflecting significant stress, alongside an increased CWSI due to stomatal closure and higher leaf temperatures. Water stress significantly reduced gas exchange variables, notably photosynthesis, which showed quicker recovery after rehydration compared to transpiration and stomatal conductance. Changes in the photochemical fluorescence parameter qP(3), defined as the coefficient of photochemical quenching measured at the third saturation pulse during fluorescence induction, reflected adjustments in photochemical activity. Five days post-rehydration, plants exhibited partial recovery, with photosynthesis regaining more rapidly than other gas exchange processes. Overall, the study underscores that water stress heavily impairs in Eucalyptus urophylla × E. grandis physiological processes, though photosynthesis recovers more readily than transpiration and stomatal conductance, depending on stress severity.

Leaf Litter Decomposition and Associated Nutrient Release Dynamics Under Varying Temperature and Precipitation in a South Asian Tropical Forest

2025-06-15

Tania Sultana , Mohammed Jashimuddin , Md. Habibul Hasan | Journal of Soil Plant and Environment

Litter decomposition plays a vital role in nutrient cycling and maintaining ecosystem functionality, particularly in forested landscapes. However, the decomposition dynamics of common tropical timber species remain underexplored in many … Litter decomposition plays a vital role in nutrient cycling and maintaining ecosystem functionality, particularly in forested landscapes. However, the decomposition dynamics of common tropical timber species remain underexplored in many regions, including Bangladesh. This study investigated the leaf litter decomposition and associated nutrient (nitrogen, phosphorus, potassium) release patterns of five widely planted timber species, Chukrasia tabularis, Dipterocarpus turbinatus, Hopea odorata, Tectona grandis, and Swietenia macrophylla on the Chittagong University campus. Using the litter bag method, decomposition rates were measured across both dry and wet seasons to assess seasonal variability and environmental influences. The results revealed that Chukrasia tabularis exhibited the highest mass loss (33% in the dry season and 60% in the wet season), followed by Hopea odorata (38% and 55%), while Tectona grandis showed the lowest decomposition rates (23% and 25%). Decomposition was most rapid in Hopea odorata during the dry season (0.57 g/month) and Dipterocarpus turbinatus in the wet season (0.89 g/month). In the wet season, decomposition rates were significantly (p < 0.05) correlated with temperature and precipitation across all species. In contrast, during the dry season, only Tectona grandis and Hopea odorata showed significant correlations with temperature, while only Chukrasia tabularis and Hopea odorata were significantly influenced by precipitation. Nutrient release patterns varied by species and nutrient type: nitrogen release was highest in Chukrasia tabularis (26.89 mg/g), phosphorus in Hopea odorata (16.53 mg/g), and potassium in Dipterocarpus turbinatus (53.53 mg/g), whereas Swietenia macrophylla consistently showed the lowest nutrient release rates. These findings highlight species-specific and seasonal variations in litter decomposition and nutrient dynamics, offering insights for forest management, species selection, and ecosystem nutrient budgeting in tropical forest plantations.

Study of some technological properties of wood branches for grown trees species at Dibis forest

2025-06-15

| Kirkuk University Journal For Agricultural Sciences

Factors influencing birch (Betula spp.) age distribution in Norway: Insights from tree ring data

2025-06-14

Marta Vergarechea , Clara Antón‐Fernández , Jane Uhd Jepsen +2 more | bioRxiv (Cold Spring Harbor Laboratory)

The age-class distribution of forests is a key indicator of both carbon stock potential and biodiversity conservation, playing a vital role in sustainable forest management. In Norway, birch (Betula spp.) … The age-class distribution of forests is a key indicator of both carbon stock potential and biodiversity conservation, playing a vital role in sustainable forest management. In Norway, birch (Betula spp.) is the most abundant tree species, covering 42% of the forest area. Understanding the factors that shape the age structure of birch is essential for developing management practices that balance timber production, carbon sequestration, and biodiversity conservation. Using data from the Norwegian National Forest Inventory (NFI), we examined the age-class distribution of birch trees across various site conditions. Our analysis revealed that middle-aged trees (50-100 years) were prevalent in most regions, while older trees were notably scarce, particularly in highly productive areas. This pattern reflects management strategies prioritizing younger, fast-growing trees to maximize economic returns. In contrast, less productive sites, which are often managed less intensively, tend to support older trees. Additionally, younger birch trees revealed significantly greater radial growth than older generations when evaluated at the same biological age (e.g., at 10 years old), particularly under favorable site conditions. These findings underscore the combined effects of site productivity, forest management, and environmental factors on growth dynamics and age-class distribution.

Interactions of tree size, competition, and tree species drive carbon accumulation in subtropical mixed forests: A case study of the coniferous-broadleaved mixed forest in Tianmu Mountain

2025-06-14

Xiaowen Dou , Tang Mengping | Ecological Indicators

Variaciones de la densidad de la madera: implicaciones en el cálculo del carbono almacenado en capueras de Misiones, Argentina

2025-06-13

Rocío Lara Arcidiácono , Carla Taraborelli , Luis Ritter +2 more | Madera y Bosques

Las variaciones en la medición de densidad, la inexistencia de datos por especie y la diversidad de expresión de densidades generan inexactitudes en los valores finales de biomasa que, en … Las variaciones en la medición de densidad, la inexistencia de datos por especie y la diversidad de expresión de densidades generan inexactitudes en los valores finales de biomasa que, en consecuencia, generan imprecisiones de los valores de existencias de carbono. El objetivo de este trabajo fue determinar la densidad anhidra (peso seco/volumen seco) de 14 especies forestales propias de capueras de la provincia de Misiones y compararlas con valores de densidad obtenidos de bibliografía, tanto de los valores en sí, como de su validez en cálculos de existencias de carbono en un inventario forestal (IF). Se recolectaron tres rodajas de madera con corteza por especie de tres ejemplares distintos a 1.3 m de altura, las mismas se dividieron en tres secciones: corteza (C), xilema exterior (E) y xilema interior (I), determinando su densidad anhidra según norma IRAM 9544 (Instituto Argentino de Normaliación y Certificación). Se obtuvo un promedio ponderado por especie con los valores de área y densidad por sección, y se contrastó con datos bibliográficos. Se compararon los resultados de existencias de carbono por estrato de un IF utilizando las densidades obtenidas en este trabajo y las encontradas en la bibliografía. Para todas las especies se encontraron diferencias significativas entre la densidad anhidra de C e I. Se generó una diferencia máxima de existencias de carbono de 4.13 t ha-1 ± 9.71 t ha-1, lo que representa una disminución de 100 344.6 t de carbono total en el estrato con mayor presencia de especies nativas (Nectandra). Se sugiere incluir C, I y E a las metodologías de medición de densidad, y utilizar estos valores en la estimación de carbono almacenado, contribuyendo a estimaciones más precisas.

Espécies arbóreas multifuncionais no estabelecimento de sistema agroflorestal sucessional na floresta de araucária

2025-06-13

Marcelo da Silva Irmão , Karine Louise dos Santos , Alexandre Siminski +1 more | Biodiversidade Brasileira

Entre as possibilidades de conciliação da produção agrícola e florestal com a resiliência dos ecossistemas naturais, figuram os sistemas agroflorestais (SAFs) por sua ampla capacidade de fornecimento de serviços ambientais. … Entre as possibilidades de conciliação da produção agrícola e florestal com a resiliência dos ecossistemas naturais, figuram os sistemas agroflorestais (SAFs) por sua ampla capacidade de fornecimento de serviços ambientais. No entanto, para a floresta ombrófila mista (FOM) ou floresta de araucária, são escassos os estudos sobre composição e estruturação espaço-temporal de SAFs, especialmente aqueles que levem em consideração os traços funcionais mensuráveis do componente arbóreo. Traços funcionais são caracteres que revelam a aptidão das espécies em sua estratégia evolutiva, sendo reflexo direto do ambiente em que elas são inseridas. A mensuração desses traços, como a área folia específica e a densidade da madeira, revelam as relações ecológicas existentes entre o meio e as espécies, permitindo agrupá-las a partir da proximidade de seus traços, formando grupos funcionais. A identificação desses grupos é útil no manejo agroecológico em sistemas produtivos, onde a adequada inserção espaço-temporal das espécies pode favorecer suas aptidões e, portanto, potencializar a produção agroflorestal. Assim, este trabalho objetivou contribuir com a identificação de espécies fornecedoras de serviços ambientais na FOM, propondo a estruturação de sistemas agroflorestais sucessionais por meio dos traços funcionais mensurados das espécies encontradas. A pesquisa se deu por meio de revisão sistemática, encontrando um total de 29 referências que atenderam aos critérios. As espécies descritas na literatura permitiram a configuração de dois modelos de SAFs para a FOM, um para espécies consideradas aquisitivas, outro para espécies consideradas conservativas, abarcando 27 espécies com usos potenciais, divididas em sete grupos funcionais.

Soils and topography drive large and predictable shifts in canopy dynamics across tropical forest landscapes

2025-06-13

Beibei Zhang , Toby Jackson , David A. Coomes +7 more | New Phytologist

Summary Tropical forests can vary enormously in their 3D structure and dynamics across surprisingly small spatial scales. However, the drivers that underpin this local‐scale variation in forest structure and dynamics … Summary Tropical forests can vary enormously in their 3D structure and dynamics across surprisingly small spatial scales. However, the drivers that underpin this local‐scale variation in forest structure and dynamics remain poorly understood. We acquired repeat airborne laser scanning data across an old‐growth tropical forest landscape in Malaysian Borneo, characterized by a steep gradient in soil fertility and topography that gives rise to large variability in canopy 3D structure. Using this unique dataset, we explored how local‐scale variation in topography and forest structure shapes rates of gap formation, closure, and canopy growth across the landscape. We found that both canopy gains and losses were 2.5–4.7 times greater in low‐lying alluvial forests on fertile soils than in nearby nutrient‐depleted kerangas forests on hilltops. Moreover, we found that variation in canopy 3D structure and dynamics was tightly coupled across the landscape, with taller and more structurally heterogeneous canopies also experiencing faster rates of gap dynamics. Our study highlights the key role that soils and topography play in shaping the structural complexity and dynamics of tropical forest landscapes.