In forests populated by bark-shedding tree species, bark-to-wood allocation ratio along the stem influences litter deposition, fuel accumulation, and nutrient and carbon dynamics. Although biomass is a more relevant metric for these ecological processes, current taper models, often based on diameter at breast height (DBH), are predominantly volumetric and largely generic. Typically, these models do not directly estimate green weight taper and often fail to incorporate adjustments for bark allocation, which is widely assumed to be an adaptive response to previous fire events. Also, the DBH-dependency of the models limit their applicability in post-logging or post-fire contexts where stems are missing or damaged, and empirical DBH data are inaccessible. Because stumps are often the only intact remnants after such disturbances, their stability makes them a more dependable and feasible biometric alternative for reconstructing stem form and formulating volume or weight taper models. This study shows that stump metrics can account for fire-induced shift in bark allocation while explaining variations in the bark-to-wood weight ratio along the stem in baseline and post-fire recovery forests. Using data from destructively sampled trees in baseline and post-fire regrowth Eucalyptus camaldulensis stands in the Kenyan coastal savanna, we developed weight-explicit taper equations with stump diameter over and under bark (DSoB, DSuB) as predictors. Parsimonious generalized least‑squares (GLS) models and spline-based generalized linear mixed models (GLMMs) were calibrated and validated through cross-validation and analytical diagnostics. All GLS models achieved high predictive accuracy (>84), confirming stump diameter as a robust predictor of segment‑level disaggregated green weight of stem, bridging the methodological gap in forest biomass and carbon assessments where DBH data are unavailable. DSoB and DSuB performed equivalently, supporting their interchangeable use. While GLS models provided ease of predictive use, spline-based GLMMs better captured diameter-dependent site interactions and localized changes in taper shape as well as bark–wood partitioning after fire. Overall, the results demonstrate that stump‑based mass-taper modelling provides a practical and sensitive tool for detecting bark allocation shifts and can be applied in baseline and fire-free plantations to test bark acclimation across regions, improving our ability to quantify bark‑driven litter production, decomposition dynamics, nutrient cycling, and CO₂ exchange.

Abstract Trees are large so they can obtain light for their leaves. Growing large takes time and therefore trees have a very slow life cycle. Some species grow even slower than others, use more energy to defend against risks from pathogens and wind, and have an even slower life cycle. Trees want to be as tall as possible, but they cannot be taller than they are, as they do not have sufficient energy to maintain larger trunks that would resist greater toppling over moments caused by wind and gravity. Forests are far worse for food production than open managed ecosystems are, which explains past deforestation. However, forests provide significant other benefits to humans, such as wood for fuel and construction and what is currently valued a carbon store for climate change mitigation. These benefits are distributed unevenly to world’s humans. Harvested wood provides local profit, but the benefit from climate change mitigation gained by leaving the wood in the forest spreads globally. Therefore, optimal forest distribution depends on who it is designed for. When optimizing far into the future and for all humankind, the world should have more forests and they should be more natural.

Climate change has increased the size and frequency of wildfires across the boreal biome. Severe wildfires in boreal forests have been found to trigger shifts from evergreen to deciduous canopies, which has cascading effects on carbon and nitrogen cycling. Ecosystem productivity and carbon uptake in boreal forests are strongly linked with nitrogen, and Earth system models increasingly depend on our understanding of the nitrogen balance to predict post-fire carbon uptake. To investigate the post-fire boreal nitrogen balance, we combined a mass balance approach and literature synthesis to estimate rates of nitrogen accumulation and nitrogen inputs across a network of 18 boreal wildfire chronosequences that varied in both wildfire regime and post-fire canopy type, comprising 527 forest stands. We found that deciduous- or mixed-dominance boreal forests establishing after severe, stand-replacing fires had the highest nitrogen accumulation rates (15.7 ± 3.8 kg ha-1 year-1), while evergreen-dominated forests establishing after surface- or mixed-severity fires had the lowest nitrogen accumulation rates (1.4 ± 1.1 kg ha-1 year-1). Annual known inputs from nitrogen deposition and biological nitrogen fixation combined, estimated from published data, largely failed to explain the rate of nitrogen accumulation, particularly in deciduous or mixed-dominance forests establishing after stand-replacing fires, suggesting that the origins of most nitrogen in these forest types remain poorly understood. As the frequency of severe wildfires increases across the boreal biome and shifts toward deciduous canopies become more common, our study reveals a large knowledge gap in the resulting nitrogen balance that needs to be resolved in order to improve predictions of forest carbon uptake.

Wood density (WD) indicates important plant functions and plays a key role in carbon cycling of forest ecosystems by affecting wood decomposition. However, how WD varies globally and how it evolved through the evolutionary history of angiosperms remain unclear. Here, by integrating data of WD, phylogeny and distributions for angiosperms worldwide, we estimated global spatiotemporal patterns of WD and their relationships with modern climate and paleoclimate. We found that mean WD decreased with latitude in the northern hemisphere but increased with latitude in the southern hemisphere. The interspecific WD variation within each geographic unit did not show clear latitudinal gradients. Temperature was the best predictor of the global geographic pattern in mean WD, while the geographic variation in mean WD across high-temperature regions could be explained by geographic variation in precipitation and precipitation seasonality (PS). Since the Cenozoic (66 million years ago (Mya)), WD increased first (until 20 Mya) and then decreased. In general, the Cenozoic WD was positively correlated with paleotemperature and negatively correlated with paleoprecipitation, especially during more arid periods. Interestingly, the evolutionary trends of WD on different continents differed, which corresponded to the divergence in WD patterns and their relationships with modern climate on different continents. Our results highlight the dominant effect of environmental temperature on global variation in angiosperm WD with an additional strong effect of PS. Our study also demonstrates the critical role of aridity and biogeographic idiosyncrasies in driving angiosperm WD evolution. (sic)(sic) (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic) (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(66(sic)(sic)(sic)(sic)(Million years ago,Mya)(sic)(sic)),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)20 Mya(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).

Human activities alter disturbance regimes, influencing forest structure and ecosystem carbon. Identifying and quantifying natural and anthropogenic disturbances at fine spatial scales are critical to assessing the role of forests in climate change mitigation. This study investigated disturbance history and carbon storage in human-impacted forests and open ecosystems at elevations of 2000-4200 m in northwestern Yunnan, China. We established 50 sampling plots along the four due orientations of a mountain peak. Using tree rings, fire scars, satellite imagery, official records, and interviews, we reconstructed historical disturbances and identified fires, logging events, landslides, and icy precipitation since the 1950s. We analyzed the impact of disturbance history and topography on ecosystem carbon storage, including pools in soil (0-30 cm), woody debris, and non-woody and woody plants. Disturbances since the 1950s were largely driven by anthropogenic activities over time, along with climate and topography. Fires and logging were common near settlements in Pinus yunnanensis forests at lower elevations, while landslides primarily occurred in steep areas of Abies georgei forests and logged areas within broadleaf mixed forests. Icy precipitation was more frequent above 3500 m on the south and west slopes in A. georgei forests. Non-forest areas at higher elevations had a mean ecosystem carbon (including soil carbon down to 30 cm) density of 146 Mg C ha-1, while forest areas averaged 270 Mg C ha-1. Fire negatively impacted soil, woody plants, and overall ecosystem carbon, whereas logging impacts were limited to woody plants and overall ecosystem carbon. Carbon storage in woody plants and total ecosystem carbon followed a hump-shaped pattern with elevation, peaking near 3200 m. Our study links disturbance histories to spatial variation in carbon pools. This study helps improve carbon management and conserve biodiversity in human-modified forests and presents a multi-source approach that could be used in other human-impacted forests.

Wood production is a major form of human land use with a heavy environmental footprint. An important strategy to limit this footprint is high-yielding tree plantations to reduce production in otherwise more extensive areas, which necessitates following optimal rotation lengths for plantation species that maximize their production volume. However, this requirement is often constrained by the lack of robust growth models. This barrier is particularly notable in southern China-a region with an extensive plantation estate that accounts for > 50 % of the country's annual wood production. For many plantation species in this region, it remains unclear whether current rotation lengths are conducive to efficient wood production. Here we parameterized growth models for six most production-important species in southern China (Cunninghamia lanceolata, Eucalyptus spp., Pinus massoniana, Castanopsis hystrix, Mytilaria laosensis, and Michelia macclurei), based on an extensive empirical dataset compiled from 394 studies that distinguished between monospecific and mixed-species stands in which the trees were growing. From these models, we derived volume-optimal rotation lengths for each species to compare with its rotation lengths currently in use. We found that across our study species, trees exhibited faster growth in mixed-species stands over monospecific stands. For most species, their volume-optimal rotation lengths were substantially longer than those currently in use, suggesting that forestry policies should consider adopting or incentivizing longer rotations to improve production. However, for Eucalyptus spp.-an economically critical species group in the region-volume-optimal rotation lengths were shorter than those currently applied, underscoring the importance of species-specific management recommendations.

Forests are susceptible to sudden disturbances, particularly those induced by wind, which can cause ecological and economic losses. Researchers have published a large number of articles from different disciplines and perspectives, leading to multidisciplinary intersections and increased literature in this field, which reduces the efficiency of traditional literature review. Employing quantitative techniques, bibliometric analysis has a great advantage in analyzing large amounts of literature and providing a visualized overview of the development and trends of the research field. This study conducted a comprehensive bibliometric analysis to elucidate the evolving landscape of research on forest wind disturbance. The methodology involved a systematic data collection process from the Web of Science Core Collection, resulting in the identification of 839 relevant publications for bibliometric analysis. The results show that there has been a consistent and steady growth in publications, with a distinct spike corresponding to Hurricane Hugo. Publications have mostly come from the United States, which also possesses the leadership in international collaboration. The standout topics include windthrow, tree motion during windstorms, European forests, wind damage risk estimation, hurricanes' impact on forests, and the long-term impacts of wind disturbances. Furthermore, four prospective directions for future research are identified, including studies into hurricanes, forest structure, climate change, and typhoon-related impacts. Our research collectively contributes to a comprehensive understanding of the dynamic landscape of forest wind disturbance research, providing a foundation for future research and strategic planning in this critical field.

Ecosystem productivity and carbon uptake in the circumpolar boreal forest are contingent on available nitrogen, which ultimately originates from inputs via deposition and biological nitrogen fixation. Nitrogen deposition rates in boreal forests are relatively small compared to other biomes, and most biological nitrogen fixation research has focused on moss-diazotroph associations. However, the relative contributions of these two primary nitrogen inputs to ecosystem nitrogen stocks have not been widely investigated. In this study, we combined a mass balance approach and literature synthesis to estimate rates of nitrogen accumulation and nitrogen inputs across a network of 18 wildfire chronosequences spanning the boreal biome. We found that nitrogen accumulation rates were strongly linked with fire regime (stand-replacing versus surface fires) and canopy dominance (deciduous versus evergreen canopies). Furthermore, a considerable amount of accumulating nitrogen in these boreal forests was unexplained by the known inputs estimated from the literature synthesis, particularly in forests with stand-replacing fire regimes and more deciduous tree cover that together had the highest nitrogen accumulation rates. This unexplained fraction of nitrogen inputs in some forests may originate from poorly quantified niches of biological nitrogen fixation. Exploring this research frontier will help improve predictions of boreal forest nitrogen cycling and carbon uptake in changing climate and wildfire regimes.

Forests benefit humans in numerous ways. Many of these benefits are greater from forests with large trees and high biomass (i.e., above-ground biomass) than from young forests with small trees. Understanding how the biomass accumulation rate depends on climate is therefore important. According to a classic theory, the biomass accumulation rate first increases until canopy closure, as leaf area and gross primary productivity increase, and decreases thereafter because leaf area cannot increase further and maintaining larger biomass is energetically costlier as living tissue increases even though its proportion of all biomass decreases. We based our modeling on this classic theory and defined relative productivity, pr indicating productivity, and relative maintenance cost, cr, signaling the expense of sustaining a unit of biomass in humid climates of the world. The biomass accumulation rate of low biomass forests is determined by pr − cr and maximal biomass by pr/cr. We then compiled a global data set from the literature, with 3,177 records to fit a parameter for the efficiency of converting surplus carbon into accumulated biomass and another parameter determining biomass at canopy closure. Based on the parameterized models, a constant temperature of 22.3°C leads to the most rapid biomass accumulation in low biomass forests, whereas 16.4°C results in greatest maximal biomass. Our parameterized model can be applied to both climate change adaptation and mitigation by optimizing land use.

Elevation-for-latitude substitution offers a tool for studying the influence of temperature and precipitation variability on vegetation structure and composition. Understanding how elevation, aspect, and slope influence vegetation patterns may help in predicting how climate change influences human forest usage and in developing strategies for ensuring the sustained provision of ecosystem services. However, most ecological studies have been carried out in protected areas, leaving forest areas used by humans to lesser attention. Therefore, we asked how elevation, aspect, and slope impact the vegetation on a human-influenced mountain. We measured woody vegetation size, richness, and composition on a mountain with plots set systematically in four cardinal directions at 100-m elevational intervals from the peak, from 1900 to 4200 m above sea level, in the Hengduan Mountains in eastern Himalaya, southwestern China. We quantified how tree maximum height, basal area, aboveground biomass (AGB), tree and shrub species richness, and woody species composition changed with elevation, aspect, and slope. Based on generalized linear models, the maximum tree height, tree basal area, and woody species AGB followed a unimodal trend along elevational gradients, with tree height and basal area peaking at 3100 m, while AGB was highest at 3300 m and somewhat higher on the southern slope. Basal area increased with slope degree. Neither tree nor shrub species richness was influenced by elevation, aspect, or slope. According to canonical correspondence analysis and TWINSPAN classification, elevation and north-south orientation of the slope were major factors influencing woody species compositions, and vegetation was classified into five types of communities. Our results indicated that the influences of elevation, aspect, and slope on woody vegetation structure were similar in a human-influenced forested mountain area as in protected mountain landscapes based on the literature. However, as forests in this area are used more intensively at low and middle elevations of the southern and western slopes, where aridity restricts tree size and AGB, climate change is likely to challenge traditional harvesting practices and place pressure on moving forest usage to higher altitudes.

Forests are susceptible to sudden disturbances, particularly those induced by wind, leading potentially to important ecological changes and economic losses. The extensive multidisciplinary literature on this topic poses challenges for traditional literature reviews. Employing quantitative bibliometric analysis, our study provides a comprehensive overview of the evolving landscape of forest wind disturbance research. A systematic data collection process from the Web of Science Core Collection identified 839 relevant publications. Results reveal a consistent growth in publications, with a notable spike corresponding to Hurricane Hugo. Most contributions originate from the United States, showcasing leadership in collaboration both nationally and institutionally. Co-citation analysis identifies three overarching research themes: factors influencing wind disturbance, the impacts of wind disturbance, and an integrated exploration of factors and impacts. Thematic map analysis unveils that key topics include windthrow, tree motion during windstorms, European forests, wind damage risk estimation, hurricane impacts on forests, and long-term impacts of wind disturbances. Thematic evolution underscores the dynamic nature of the research themes, with hurricanes and mortality emerging as foundational, while forest structure, tree stability, and Picea abies exhibit evolving complexities. The study also identifies prospective research directions, emphasizing hurricanes, forest structure, climate change, and typhoon-related impacts. This research contributes to a nuanced understanding of the dynamic forest wind disturbance landscape, providing a foundation for future research and enabling better-informed and more effective management decisions.

AimWoody and herbaceous habits represent one of the most distinct contrasts among angiosperms, and the proportion of woody species in floras (i.e., "woodiness" hereafter) represents a fundamental structural element of plant diversity. Despite its core influence on ecosystem processes, spatio-temporal patterns in woodiness remain poorly understood. Here, we aim to demonstrate the global spatio-temporal patterns in angiosperm woodiness and their relationship with environmental factors. LocationGlobal. Time periodCenozoic, 66 Ma to present. Major taxa studiedAngiosperms. MethodsUsing newly compiled data on the growth forms and distributions of c. 300,000 angiosperm species and an angiosperm phylogeny, we mapped the current global geographical patterns in angiosperm woodiness, reconstructed ancestral states of growth forms through the angiosperm phylogeny and demonstrated the Cenozoic evolutionary dynamics of woodiness. We evaluated the relationships between woodiness and current climate and palaeoclimate. ResultsWe found that c. 42.7% of angiosperms are woody. Woodiness decreased spatially from the equator towards high latitudes, temporally since the early Cenozoic. Temperature was the best predictor of the spatio-temporal decline in woodiness and was positively correlated with woodiness. Despite the temporal decline in woodiness, macroevolutionary herbaceous-to-woody transitions increased through time and contributed to the evolution of woody floras in temperate drylands, whereas the opposite transitions decreased through time and contributed to herbaceous floras in tropical and subtropical drylands. Main conclusionsOur study improves understanding of the spatio-temporal dynamics of angiosperm woodiness. Our findings suggest that temperature is likely to be a determinant of spatio-temporal variations in woodiness, highlighting the role of temperature in maintaining the growth form composition of ecosystems. Our study also calls for attention to growth form transitions (e.g., secondary woodiness) in temperate drylands that have been neglected before.

<p>Plant biodiversity can be structured into different growth forms (i.e. woody vs. herbaceous) with divergent distributions, evolutionary histories, and relationships with climate thus they should be separately analyzed to better understand plant diversity. Flowering plants (angiosperms) are the most successful group of plants and have a diversity of growth forms that differs from other groups such as gymnosperms, all of which are woody species. However, there is still a gap in current growth form databases to cover most angiosperms. To fill the gap, this study collect data on growth forms of angiosperm species from published floras, online databases, and peer-reviewed journal articles and compiled a massive database of growth forms (woody and herbaceous, 300,750 species). Combined with distributions of 332,293 species, we mapped the current global geographical patterns in woody and herbaceous species as well as their relative proportion and assess their relationship with climate. This study also reconstructed ancestral states of growth forms through the angiosperm phylogeny to demonstrate the Cenozoic evolutionary dynamics of growth forms and explore the evolutionary transitions between the two growth forms.</p>

Seed rain phenology (the start and end date of seed rain) is an essential component of plant phenology, critical for understanding population regeneration and community dynamics. However, intra- and inter-annual changes of seed rain phenology along environmental gradients have rarely been studied and the responses of seed rain phenology to climate variations are unclear. We monitored seed rain phenology of four forest communities in four years at different elevations (900 m, 1450 m, 1650 m, 1900 m a.s.l.) of a subtropical mountain in Central China. We analyzed the spatiotemporal patterns of seed rain phenology of 29 common woody plant species (total observed species in the seed rain), and related the phenological variations to seed number and climatic variables using mixed-effect models with the correlation matrix of phylogeny. We found that changes in the period length were mainly driven by the end rather than the start date. The end date and the period length of seed rain were significantly different between the mast and non-mast seeding years, while no significant elevation-related trend was detected in seed rain phenology variation. Seed number, mean temperature in spring (T spr ), and winter (T win ), summer precipitation (P sum ) had significant effects on seed rain phenology. When T spr increased, the start date of seed rain advanced, while the end date was delayed and the seed rain period length was mainly prolonged by a higher seed number, T win and P sum . Forest canopy might have a buffering effect on understory climatic conditions, especially in precipitation that lead to difference in seed rain phenology between canopy and shrub species. Our novel evidence of seed rain phenology can improve prediction of community regeneration dynamics in responding to climate changes.

Biodiversity has a pivotal role to play in providing ecosystem goods and services, which is under threat due to various anthropogenic activities. This chapter is based on literature review to assess the role of agroforestry to enhance biodiversity and ecosystem services in Southeast Asian agricultural landscapes. The reviewed literature was analysed through narrative qualitative and narrative comparative methods. The review provides substantial evidence that agroforestry systems can conserve species diversity and enhance ecosystem services. Farmers’ cultivating diverse species in agroforestry is the key to enhance biodiversity on farmlands that can also lessen the pressure on local forest. Careful agroforestry plantation design will not only increase the multiple ecosystem functions but can also create corridors and buffer zones to support natural habitats, to reduce human and wildlife conflict. The case of human conflicts with Asian elephants is an obvious example. From ethical ground to support elephant’s right to survive, further research on agroforestry modelling is required to benefits both humans and elephants.

We developed a more realistic modeling framework by integrating stem photosynthesis into the canopy carbon assimilation model to compare the photosynthetic productivity between the stem and leaf of Eucalyptus urophylla plantations. Stems of Eucalyptus species with smooth outer bark have photosynthetic green tissue that can recycle internal stem CO2. However, the potential contribution of stem photosynthesis to forest productivity has not previously been adequately quantified, and we also do not know how it compares to leaf photosynthetic productivity. To assist in addressing this knowledge gap, we conducted field surveys in Eucalyptus urophylla plantations of different ages and developed a more realistic modeling framework by integrating stem photosynthesis into the existing canopy carbon assimilation model. We calculated the proportion of tree stems shaded by neighboring tree trunks based on Poisson spatial point process. Under the stand density of 2000 trees per hectare, the light absorption area of tree trunks of 2-year-old and 7-year-old E. urophylla plantations were 0.11 (± 0.15) and 0.35 (± 0.12) m2 stem m−2 land, the stem photosynthetic productivity (GPPstem) was 0.72 (± 0.45) and 1.81 (± 1.12) mol C m−2 month−1, and the ratios of GPPstem to leaf photosynthetic productivity (GPPleaf) were 5.10 and 8.17

Forest above-ground biomass (AGB) accumulation is widely considered an important tool for mitigating climate change. However, the general pattern of forest AGB accumulation associated with age and climate gradients across various forest functional types at a global scale have remained unclear. In this study, we compiled a global AGB data set and applied a Bayesian statistical model to reveal the age-related dynamics of forest AGB accumulation, and to quantify the effects of mean annual temperature and annual precipitation on the initial AGB accumulation rate and on the saturated AGB characterizing the limit to AGB accumulation. The results of the study suggest that mean annual temperature has a significant positive effect on the initial AGB accumulation rate in needleleaf evergreen forest, and a negative effect in broadleaf deciduous forest; whereas annual precipitation has a positive effect in broadleaf deciduous forest, and negative effect in broadleaf evergreen forest. The positive effect of mean annual temperature on the saturated AGB in broadleaf evergreen forest is greater than in broadleaf deciduous forest; annual precipitation has a greater negative effect on the saturated AGB in deciduous forests than in evergreen forests. Additionally, the difference of AGB accumulation rate across four forest functional types is closely correlated with the forest development stage at a given climate. The contrasting responses of AGB accumulation rate to mean annual temperature and precipitation across four forest functional types emphasizes the importance of incorporating the complexity of forest types into the models which are used in planning climate change mitigation. This study also highlights the high potential for further AGB growth in existing evergreen forests.