Aboveground Biomass Storage Research Articles

The Effect of Tree Pruning on Growth and Potential of Carbon Storage in Aboveground Biomass in Royal Park Rajapruek in Chiang Mai Province

The Effect of Tree Pruning on Growth and Potential of Carbon Storage in Aboveground Biomass in Royal Park Rajapruek in Chiang Mai Province

Exploring the relationship between tree diversity and carbon storage in aboveground biomass of coffee agroforestry systems in southern Manabí, Ecuador

ABSTRACT The study was conducted at three sampling sites in the province of Manabí, Ecuador, designated for coffee production under an agroforestry system (AFS). A total of 21 plant species were recorded, and the carbon stored in live aboveground biomass was estimated. The results showed that coffee-based AFS has a high potential for carbon storage, and species diversity is related to the structural parameters and diversity of each sampling site. The implementation of coffee-based AFS is an effective strategy for the conservation of native flora and climate change mitigation in the area.

Aboveground Biomass and Endogenous Hormones in Sub-Tropical Forest Fragments

Associated endogenous hormones were affected by forest fragmentation and significantly correlated with aboveground biomass storage. Forest fragmentation threatens aboveground biomass (AGB) and affects biodiversity and ecosystem functioning in multiple ways. We ask whether and how forest fragmentation influences AGB in forest fragments. We investigated differences in AGB between forest edges and interiors, and how plant community characteristics and endogenous hormones influenced AGB. In six 40 m × 40 m plots spread across three forest fragments, AGB was significantly higher in plots in the forest interior than in those at the edge of forests. The proportion of individuals with a large diameter at breast height (DBH > 40 cm) in the forest edges is higher than that in the forest interiors. Further, trees within a 15–40 cm DBH range had the highest contribution to AGB in all plots. Trees in interior plots had higher abscisic acid (ABA) and lower indole-3-acetic acid (IAA) concentrations than those in edge plots. In addition, AGB was significantly positively and negatively correlated with ABA and IAA concentrations at the community scale. In this study, we provide an account of endogenous hormones’ role as an integrator of environmental signals and, in particular, we highlight the correlation of these endogenous hormone levels with vegetation patterns. Edge effects strongly influenced AGB. In the future, more endogenous hormones and complex interactions should be better explored and understood to support consistent forest conservation and management actions.

Determining the Effects of Changes in Land Use on Carbon Amount in Above-Ground Biomass with NDVI

<p>In terms of sustainable land use management, it is extremely important to reveal the land conditions and the changes that occur on the land in certain periods. In this study, using CORINE data for Düzce province, land use status and transitions between land-use classes over 28 years were investigated. In addition, changes in carbon storage in above-ground biomass were determined for each land-use and land transition using Landsat satellite images for the years 1990 and 2018. 28 years, artificial surfaces increased from 3,852 hectares to 9,058 hectares. While agricultural areas increased by 11.5% to 114,650 hectares, forest and semi-natural areas decreased by 14% to 122,955 hectares. 96.7% of the increase in agricultural areas was land converted from forest areas. While the amount of carbon stored in the forest and semi-natural areas increased by 27.9%, it increased by 30.5% in agricultural areas. With land transitions, 17.8% of the total carbon (14,407 tons) was transferred from one land use to another. In terms of annual land-use change rate between 1990 and 2018, the highest rate of land-use change was in the post-earthquake 2000-2006 period. The information in this study will make important contributions to policymakers in land management and planning.</p>

Opportunity Costs of In Situ Carbon Storage Derived by Multiple-Objective Stand-Level Optimization—Results from Case Studies in Portugal and Germany

Considering in situ carbon storage in forest management has gained momentum under increasing pressure to decarbonize our economies. Here, we present results from case studies in Portugal and Germany showing the opportunity costs of in situ carbon storage derived by multiple-objective optimization. We used a stand-level model to optimize land expectation value under uncertainty as a reference, then derived opportunity costs by including the enhancement of the average carbon storage in aboveground biomass as a second objective. Using the optimal (compromise) solution when considering both objectives simultaneously, we show opportunity costs of EUR 119 (Portugal) and EUR 68 (Germany) per Mg CO2eq. These opportunity costs are higher than conservative, but lower than alternative cost estimates for future damages caused by current CO2 emissions. An important result was that suggested reference solutions in both countries (though only for low discount rates in Portugal) were mixed forests without clearfelling. In Germany, this implicitly elevated carbon storage. Such “closer-to-nature-forest-management” systems were also mostly suggested by the optimization tool when carbon storage was an objective.

Temporal dynamics of carbon storage in a Mediterranean mountain scrubland managed by prescribed fire

Farmland abandonment and reduction of grazing activity, mainly in mountain areas with remote access and ageing population, have been contributing to shrub encroachment in such territories and, consequently, to increase fuel load available for triggering wildfires. Accordingly, it is necessary to use vegetation management practices in order to reduce wildfire risk, prescribed fire being one of the most common techniques used in the Mediterranean region. This research focused in the effects of a prescribed fire (PF) applied in Montesinho Natural Park (PNM), NE Portugal, on the temporal dynamics of carbon storage in mineral soil, litter layer (organic horizon), and shrub biomass. Before PF and thirty-six months after PF, aboveground shrub biomass was collected in areas of 1 m2 in 11 plots randomly distributed in the experimental shrub area. Also, in the same plots, litter thickness was measured and soil samples were collected before, two, six and thirty-six months after PF, in order to assess carbon concentration, bulk density and coarse elements content. Despite low to moderate fire intensity, carbon storage changes were observed in all compartments evaluated. Thirty-six months after PF, carbon storage in aboveground biomass of shrub species (7.4 Mg C ha−1) was roughly two-thirds of that recorded prior to PF, and in litter layer (1.6 Mg C ha−1) it was about half of that in the original situation (before PF). In contrast, the mineral soil showed a 10% carbon increase (6.4 Mg C ha−1). Based on the balance between losses (shrub species and litter layer) and gains (mineral soil), at the end of the monitoring period (36 months), there was an annual positive rate of carbon storage, equivalent to 0.2 Mg C ha−1 year−1. Even after anthropogenic disturbances, such as prescribed fire, shrub communities constitute important terrestrial carbon pools; hence, these ecosystems might play an important role in mitigating climate change.

Evaluation on Carbon Storage in Aboveground Biomass of Yang na at Plant Genetic Protection Area, Ubon Ratchathani Province

Evaluation on Carbon Storage in Aboveground Biomass of Yang na at Plant Genetic Protection Area, Ubon Ratchathani Province

First report on carbon storage in a warm-temperate mangrove forest in South Africa

Carbon (C) storage by vegetated coastal habitats (mangroves, salt marshes and seagrasses) is globally recognized as a critical ecosystem service. Research efforts have therefore focused on quantifying C stored in these “blue carbon” ecosystems but a notable knowledge gap still exists for certain geographical regions. This study aimed to provide the first comprehensive assessment of C storage in South African warm temperate mangroves by quantifying the C storage in aboveground biomass and soil C pools associated with the mangrove forest at the Nxaxo Estuary. C storage variability was also related to mangrove forest structure and soil environmental variables. C storage was quantified using standardized protocols for aboveground (live trees, leaf litter, pneumatophores) and soil C pools at five Avicennia marina sites. The results showed soil C storage to be spatially variable while aboveground C pools were similar between intertidal zones within the sites. The soil C pool made the largest contribution to total C storage at each site and ranged from 176.91 ± 4.5MgC.ha−1 to 262.53 ± 18.8 MgC.ha−1. Of the aboveground carbon pools, live trees made the largest contribution and ranged from 2.25 ± 1.0 MgC.ha−1 to 9.56 ± 3.6 MgC.ha−1. Across all sites, average C storage for all pools was 234.9 ± 39.16 MgC.ha−1, which falls within the range reported for mangroves at other southern hemisphere range limits. Variability in soil C was linearly related to soil organic matter but this relationship was inconsistent between different soil depth intervals that were sampled. Total C storage was inversely related to mangrove tree density. This study confirms the need for more blue carbon studies to quantify C storage in under-represented geographical areas and to investigate factors that drive variability in C storage at different spatial scales.

Estructura, composición florística y almacenamiento de carbono en bosques nativos del páramo de Anaime, Tolima, Colombia

Los páramos tienen alta importancia ambiental por su alto endemismo, su regulación hídrica y su almacenamiento de carbono. En este trabajo se caracterizó la estructura y composición poblacional de la vegetación arbórea, se estimó el almacenamiento de carbono en biomasa aérea y el potencial de reducción de emisiones por deforestación, y se priorizó los tipos de bosques nativos en los esfuerzos de conservación en la Reserva Natural Semillas de Agua (RNSA) en el páramo de Anaime, Tolima, Colombia. En cada tipo de bosque (achaparrado, maduro y subpáramo), se establecieron nueve parcelas de muestreo de 10 x 15 m, en donde se midieron todos los individuos con un diámetro del tronco a la altura del pecho (dap) ≥ 10 cm. La biomasa aérea se estimó a través de un modelo alométrico multi-especie generado localmente. Las especies importantes, en términos de índice de valor de importancia y de almacenamiento de carbono, fueron Weinmannia auriculata y Miconia sp. El mayor almacenamiento de carbono se alcanzó en los bosques del subpáramo, seguido de los maduros y achaparrados (242 vs 147 vs 25 Mg/ha, respectivamente). Los bosques en la RNSA almacenan 3,2 Tg CO2e en biomasa aérea, de los cuales se podrían perder 0,2-0,5 Tg CO2e en 20 años con una deforestación anual de 0,78 y 0,28%, respectivamente. Estas reducciones de gases de efecto invernadero podrían ser comercializadas en un potencial proyecto REDD+, que ayuden a conservar estas áreas de bosque. Los bosques achaparrados y del subpáramo deberían ser priorizados en los esfuerzos de conservación debido a su diversidad, endemismo y a su gran cantidad de carbono en el caso de los bosques maduros.

Wood density is a sustainability indicator for the management of dry zone homegarden agroforests: Evidences from biodiversity–ecosystem function relationships

Abstract Recent studies have advanced our understanding regarding the niche complementarity and mass ratio effects on the ecosystem function, in both natural and experimental systems. However, biodiversity–ecosystem function (BEF) relationships may be fundamentally different across dense-wooded and light-wooded species, as they are clustered at two opposite extremes of the wood economics spectrum. Here we analyzed BEF relationships through mediations of functional dominance (i.e. community-weighted mean, CWM) and functional divergence (FDvar) of plant maximum height (H) while accounting for the effects of other characteristics of homegardens, across dense-wooded, light-wooded and all species, by using structural equation modelling (SEM) on 45 homegarden agroforestry systems in the dry zone of Sri Lanka. The dense-wooded SEM accounted for 69% variation in aboveground biomass through significant positive direct effects of CWM H (β = 0.51) and FDvar H (β = 0.20), and indirect effect of species diversity via FDvar H on aboveground biomass (β = 0.12). Although the light-wooded SEM accounted for 19% variation in aboveground biomass, the BEF relationships were non-significant. Regardless of SEMs, FDvar H but not CWM H was significantly positively related to species diversity. None of the BEF relationships was statistically significant when dense-wooded and light-wooded species were mixed. From a theoretical aspect, these positive BEF relationships are driven by both dominant and complementarity dense-wooded species. From a practical aspect, the positive BEF relationships support the feasibility of UN Reducing Emissions from Deforestation and Forest Degradation (REDD+) initiative in studied agroforests, which aims to enhance carbon storage in aboveground biomass while conserving biodiversity. Hence, this study suggests that wood density is a potential sustainability indicator for better management of agroforest-ecosystem while driving positive BEF relationships.

Global patterns of aboveground carbon stock and sequestration in mangroves.

In order to contribute to understand the factors that control the provisioning of the ecosystem service of carbon storage by mangroves, data on carbon stock and sequestration in the aboveground biomass (AGB) from 73 articles were averaged and tested for the dependence on latitude, climatic parameters, physiographic types and age. Global means of carbon stock (78.0 ± 64.5 tC.ha-1) and sequestration (2.9 ± 2.2 tC.ha-1.yr-1) showed that mangroves are among the forest ecosystems with greater capacity of carbon storage in AGB per area. On the global scale, carbon stock increases toward the equator (R²=0.22) and is dependent on 13 climatic parameters, which can be integrated in the following predictive equation: Carbon Stock in AGB = -16.342 + (8.341 x Isothermality) + (0.021 x Annual Precipitation) [R²=0.34; p < 0.05]. It was shown that almost 70% of carbon stock variability is explained by age. Carbon stock and sequestration also vary according to physiographic types, indicating the importance of hydroperiod and edaphic parameters to the local variability of carbon stock. By demonstrating the contribution of local and regional-global factors to carbon stock, this study provides information to the forecast of the effects of future climate changes and local anthropogenic forcings on this ecosystem service.

An analysis of forest biomass changes using geospatial tools and ground survey data: a case study in Yok Don national park, Central Highlands of Vietnam

Vietnam conducts a national forest survey every five years using optical satellite imagery as Landsat, SPOT satellites and ground survey data. However, estimation of change in biomass due to change in forest types has not been of research interest despite of its importance in the face of climate change and applicability for REDD implementation. In this study, we used SPOT HRV satellite data of 2004, 2011 and ground survey data for analysis of changes in biomass of forest cover in Yok Don National Park, Central Highlands of Vietnam. This method has been effectively employed for mapping of land cover with overall classification accuracy of 84.30% to 86.63%. The results demonstrated that between 2004 and 2011, the biomass of Evergreen broad leaved rich forest decreased by 2.95 Megatons, biomass of the Evergreen broad leaved medium forest decreased by 0.09 Mega tons and biomass of the Dry open dipterocarps medium forest decreased 2.20 Mega tons. In that period, biomass of the Evergreen broad-leavedpoor forest increased by 0.02 Mega tons and biomass of the Dry open dipterocarps-poor forest increased by 0.91 Mega tons.References Bao Huy, 2008: Methodology for research on CO2 sequestration in natural forests to join the program of reducing emission from deforestation and degradation-REDD. Journal of Agriculture and Rural Development, MARD, 2008, pp. 1-10. Bhishma, P. et al., 2010: Forest carbon stock measurement-Guidelines for measuring carbon stocks in community-managed forest. Asia Network for Sustainable Agriculture and Bioresource (ANSAB), 79 pp. Brown, S., 1997. Estimating biomass and biomass change of tropical forests: a Primer. FAO Forestry paper–134.ISBN 92-5-103955-0. Brown, S., 2002: Measuring carbon in forests: current status and future challenges. Environmental Pollution, 116(3): 363-372.. Canh N. X. et al., 2009: Conservation planning and Sustainable Development of Yok Don National Park in 2010-2020,150pp. Chaiyo, U., Garivait, S., Wanthongchai, K., 2011: Carbon storage in Above-Ground Biomass of Tropical Deciduous Forest in Ratchaburi Province, Thailand. World Academy of Science, Engineering and Technology, pp. 636-641.. Chave, J., Andalo, C., Brown, S., Cairns, M.A. et al., 2005: Tree allometry and improved estimation of carbon stocks and balance in tropical forests. Oecologia Vol. 145, No. 1, pp. 87-99. Guide to the Kyoto Protocol to United Nations framework convention on climate change, 1998. Howarth, Wickware, 1981: Spatial analysis of land cover and land use in evaluating land degradation in Northwestern Al-Mafraq city, Jordan, pp. 55-62. IPCC, 2003: Good Practice Guidance for Land Use, Land-Use Change and Forestry. IPCC National Greenhouse Gas Inventories Programme Technical Support Unit. Printed in Japan.ISBN 4-88788-003-0.2003, 590pp. IPCC, 2006: Guidelines for National Greenhouse Gas Inventories. Volume 4: Agriculture, Forestry and Other Land Use. Chapter 4. Forest land, 83 pp. Losi, C.J. et al., 2003: Analysis of alternative methods for estimating carbon stock in young tropical plantations. Forest Ecology and Management, 184(1-3): 355-368. Lu, D. S., 2006: The potential and challenge of remote sensing-based biomass estimation. International Journal of Remote Sensing. Vol. 27, No. 7,: 1297-1328. Luong, N.V., 2011: Essay to use remote sensing images to estimate biomass as a basis for calculating the amount of CO2 sequestration by vegetation cover in in Yok Don National Park, Highlands of Viet Nam.Scientific Conference "Research, development and application of space technology-2011".ISBN: 987-604-913-032-8. Hanoi. 9pp. Ministry of Agriculture and Rural Development (MARD).Circular 34/TT-BNN issued by (MARD) of Vietnamese government, 2009: Quy định tiêu chí xác định và phân loại rừng (in Vietnamese), translated by Luong N.V-Regulation on criteria for identifying and classifying forest (in English), 5, 3. Phat, N.K. et al., 2004 : Appropriate measures for conservation of terrestrial carbon stocks- Analysis of trends of forest management in Southeast Asia. Forest Ecology and Management, 191(1-3): 283-299. Thin, N. N. et al., 2007: The vegetation of Yok Don National Park, a special ecosystem in Central Highlands of Vietnam, 2007,6, 4-5. Trung, T. V.The tropical forest ecosystem in Vietnam.Science and Technics Publishing House, Hanoi. Chapter IV, 1998, 291pp. Trung, T.V.The vegetation cover in Vietnam. Science and Technics Publishing House, Hanoi. Chapter IV, V, 1978: 276 pp. UNESCO Paris, 1973. International classification and mapping of vegetation. Published by the United Nations Educational, Scientific and Cultural Organization. ISBN 92-3-001046-4 LC No. 72-96442, 1973, 102pp. UN-REDD in Vietnam programme, 2012: Guidelines on Destructive Measurement for Forest Biomass Estimation for technical staff use. (Version for discussion). UN-REDD Vietnam Programme, 2012: Tree allometric equation development for estimation of forest above-ground biomass in Viet Nam. Part A - Introduction and Background of the Study Viet Nam.

Forty years of forest measurements support steadily increasing aboveground biomass in a maturing,Quercus-dominant northeastern forest1

Abstract Repeated measurements of permanent plots in northeastern U.S. forests provide an opportunity to assess how stand-level changes impact carbon storage in aboveground biomass over time. We used 42 years of census data for >6000 individual trees in a 2.9- ha permanent plot at the Harvard Forest (Petersham, MA, USA) to determine how changes in stand age, structure, and species composition affect carbon storage in aboveground biomass in a Quercus-Acer forest. From 1969 to 2011, the biomass of live trees increased linearly (R2 = 0.99, p = 0.0002), from 150 Mg ha−1 to 268 Mg ha−1, confirming that this ca. 110-year-old stand is still in the aggradation phase of stand development. Over time, a higher proportion of the stand's biomass occurs in large trees. Quercus rubra L. (red oak) accounts for >80 percent of the increase in aboveground biomass due to the rapid growth of dominant stems and low canopy mortality rates. Changes in the biomass of live Acer rubrum L. (red maple) stagnated after 1991, in co...

Carbon and nitrogen dynamics of native &amp;lt;i&amp;gt;Leymus chinensis&amp;lt;/i&amp;gt; grasslands along a 1000 km longitudinal precipitation gradient in northeastern China

Abstract. Understanding how ecosystem carbon (C) and nitrogen (N) cycles respond to the variability of precipitation can help us assess the effects of global climate change on terrestrial ecosystem structure and function. We investigated the contributions of aboveground biomass, litter, root, soil and microbial communities to ecosystem C and N processes at 14 sites along a 1000 km precipitation gradient in native Leymus chinensis grasslands of northeastern China. The results show that aboveground biomass C and N increased gradually, while no significant regional trends in litter and root biomass were found with increasing mean annual precipitation (MAP) along the gradient. Soil respiration increased first and then decreased from the dry to mesic sites, which could be ascribed to the relative changes in temperature, soil fungal : bacterial biomass and N availability. Surprisingly, N mineralization varied only slightly along the gradient, likely due to the decreases of soil organic matter quality (i.e., C : N). Stepwise regression models indicated regional soil C and N content positively correlated with MAP and clay content. Overall, C and N sequestration increased 3.2- and 1.8-fold with increasing MAP in terms of C and N storage in aboveground biomass, roots, litter and soil. It was concluded from the current study that regional precipitation variability strongly influences ecosystem C and N dynamics. The ecosystem C and N sequestration are primarily modulated by annual precipitation and soil texture, while the C and N turnover are largely controlled by microbial community composition, temperature and soil quality in L. chinensis grasslands across the large-scale precipitation gradient.

Will more nitrogen enhance carbon storage in young forest stands in central Appalachia?

Many temperate deciduous forests in the Eastern US are secondary, regrowing forests and have experienced decades of elevated inputs of acidic compounds and biologically available nitrogen (N) from the atmosphere. These young forests play an important role in the global carbon (C) cycle as C sinks, and it is possible that acidic deposition will influence the strength and longevity of this sink. We used the Fernow Experimental Forest Long Term Soil Productivity (LTSP) experiment near Parsons, WV to evaluate how 13years of experimental N additions has affected ecosystem C storage and stand level dynamics in a young temperate deciduous forest. Specifically we examined whether N additions: (1) directly increased aboveground growth of regenerating trees but did so in a way that was independent of the indirect effects of soil acidification; (2) directly (independent of acidification effects) increased forest floor and soil C pools, and decreased the fine root C pool; and (3) lowered stand density and diversity. We also tested whether tree species were differentially affected by either N fertilization or soil acidification.Thirteen years of ammonium sulfate additions to a regenerating deciduous forest stimulated C storage by 22% – even in a region with historically high levels of atmospheric N deposition. This response was driven primarily by a 27% increase in C storage in aboveground biomass and to a lesser extent by a 35% increase in C stored in the smaller forest floor pool. Despite the dominance of a single tree species (Prunus pensylvanica), the overall response may have been tempered by reductions in stand density and was only detectable when the changes in all species were included, rather than when only the changes in the dominant species were examined. Indirect acidification effects were found to increase C accumulation in the forest floor and decrease the number of different tree species.In the short-term it is likely that N deposition will stimulate forest growth and C storage in young temperate deciduous forests. However, given the differential responses observed for longer-lived tree species versus the positive response for short-lived species, it appears that the long-term effects of N deposition on C storage in temperate deciduous forests may be different than the short-term effects, and may even be negative.

Biomass storage in low timber productivity Mediterranean forests managed after natural post-fire regeneration in south-eastern Spain

Despite the low timber productivity of Mediterranean Pinus halepensis Mill. forests in south-eastern Spain, they are a valuable carbon sequestration source which could be extended if young stands and understories were considered. We monitored changes in biomass storage of young Aleppo pine stands naturally regenerated after wildfires, with a diachronic approach from 5 to 16 years old, including pine and understory strata, at two different quality sites (dry and semiarid climates). At each site, we set 21 permanent plots and carried out different thinning intensities at two ages, 5 and 10 years after fires. We found similar post-fire regeneration capacity at both sites in terms of total above-ground biomass storage ~6 Mg ha−1 (3 Mg ha−1 of the above-ground pine biomass plus 3 Mg ha−1 of the above-ground understory biomass), but with a contrasting pine layer structure. Generally, across the diachronic study, the earlier thinning reduced biomass stocks at both sites, except for the best quality site (the dry site), where the earliest thinning (applied at post-fire year 5) enlarged carbon storage by 11 % as compared to non-thinned plots. We found root:shoot ratios of an average 0.37 for the pine layer and 0.45 for the understory layer. These results provided new information which not only furthers our understanding of carbon sequestration in low timber productivity Mediterranean forests, but will also help to develop new guidelines for sustainable management adapted to the high-risk terrestrial carbon losses of fire-prone areas.

Variación de la biomasa forestal en el sur de Brasil: impacto de los árboles de Araucaria

A variety of environmental and biotic factors determine vegetation growth and affect plant biomass accumulation. From temperature to species composition, aboveground biomass storage in forest ecosystems is influenced by a number of variables and usually presents a high spatial variability. With this focus, the aim of the study was to evaluate the variables affecting live aboveground forest biomass (AGB) in Subtropical Moist Forests of Southern Brazil, and to analyze the spatial distribution of biomass estimates. Data from a forest inventory performed in the State of Rio Grande do Sul, Southern Brazil, was used in the present study. Thirty-eight 1-ha plots were sampled and all trees with DBH > or = 9.5cm were included for biomass estimation. Values for aboveground biomass were obtained using published allometric equations. Environmental and biotic variables (elevation, rainfall, temperature, soils, stem density and species diversity) were obtained from the literature or calculated from the dataset. For the total dataset, mean AGB was 195.2 Mg/ha. Estimates differed between Broadleaf and Mixed Coniferous-Broadleaf forests: mean AGB was lower in Broadleaf Forests (AGB(BF)=118.9 Mg/ha) when compared to Mixed Forests (AGB(MF)=250.3 Mg/ha). There was a high spatial and local variability in our dataset, even within forest types. This condition is normal in tropical forests and is usually attributed to the presence of large trees. The explanatory multiple regressions were influenced mainly by elevation and explained 50.7% of the variation in AGB. Stem density, diversity and organic matter also influenced biomass variation. The results from our study showed a positive relationship between aboveground biomass and elevation. Therefore, higher values of AGB are located at higher elevations and subjected to cooler temperatures and wetter climate. There seems to be an important contribution of the coniferous species Araucaria angustifolia in Mixed Forest plots, as it presented significantly higher biomass than angiosperm species. In Brazil, this endangered species is part of a high diversity forest (Araucaria Forest) and has the potential for biomass storage. The results of the present study show the spatial and local variability in aboveground biomass in subtropical forests and highlight the importance of these ecosystems in global carbon stock, stimulating the improvement of future biomass estimates.

Sinks for nitrogen inputs in terrestrial ecosystems: a meta‐analysis of 15N tracer field studies

Effects of anthropogenic nitrogen (N) deposition and the ability of terrestrial ecosystems to store carbon (C) depend in part on the amount of N retained in the system and its partitioning among plant and soil pools. We conducted a meta-analysis of studies at 48 sites across four continents that used enriched 15N isotope tracers in order to synthesize information about total ecosystem N retention (i.e., total ecosystem 15N recovery in plant and soil pools) across natural systems and N partitioning among ecosystem pools. The greatest recoveries of ecosystem 15N tracer occurred in shrublands (mean, 89.5%) and wetlands (84.8%) followed by forests (74.9%) and grasslands (51.8%). In the short term (< 1 week after 15N tracer application), total ecosystem 15N recovery was negatively correlated with fine-root and soil 15N natural abundance, and organic soil C and N concentration but was positively correlated with mean annual temperature and mineral soil C:N. In the longer term (3-18 months after 15N tracer application), total ecosystem 15N retention was negatively correlated with foliar natural-abundance 15N but was positively correlated with mineral soil C and N concentration and C:N, showing that plant and soil natural-abundance 15N and soil C:N are good indicators of total ecosystem N retention. Foliar N concentration was not significantly related to ecosystem 15N tracer recovery, suggesting that plant N status is not a good predictor of total ecosystem N retention. Because the largest ecosystem sinks for 15N tracer were below ground in forests, shrublands, and grasslands, we conclude that growth enhancement and potential for increased C storage in aboveground biomass from atmospheric N deposition is likely to be modest in these ecosystems. Total ecosystem 15N recovery decreased with N fertilization, with an apparent threshold fertilization rate of 46 kg N x ha(-1) x yr(-1) above which most ecosystems showed net losses of applied 15N tracer in response to N fertilizer addition.

Carbon Storage in Above-Ground Biomass of Tropical Deciduous Forest in Ratchaburi Province, Thailand

Carbon Storage in Above-Ground Biomass of Tropical Deciduous Forest in Ratchaburi Province, Thailand

Impact of Land-Use Change on Carbon Stocks in Meadow Steppe of Northeast China

An improved understanding of changes in carbon storage of terrestrial ecosystems is very important for assessing the impacts of increasing atmospheric CO2 concentration and climate change on the terrestrial biosphere. Accurately predicting terrestrial carbon (C) storage requires understanding the carbon stock, because it helps us understand how ecosystems would respond to natural and anthropogenic disturbances under different management strategies. We investigated organic C storage in aboveground biomass, litter, roots, and soil organic matter (SOM) in five land-use types (i.e. artificial pasture, AP; natural meadow, NM; corn plantation, CP; temperate savanna, TS; and bush wood, BW) in meadow steppe of Northeast China. The primary objective of this study was to ascertain the impact of different land-use types on the carbon stock. The total C storage (including C stored in aboveground biomass, litter, roots, and 0–100-cm soil layers) did not significantly differ between one and another type among the five pairs (P&gt;0.05), with the exception of AP2-BW pair. The total C storage changes in value varying from 5958.09 g C m-2 for plot NM2 to 11922.87 g C m-2 for plot CP1. The C stored in the aboveground biomass was less than 1177.96 g C m-2, accounting for negligible amounts (&lt;1% of the total) of total C storage in the ecosystem except corn plantation. The amount of C stored in SOM accounted for less than 85% of the total C storage in TS, AP2, and NM3, and the C stored in litter was very low (&lt;1.5%), compared to other pools in the ecosystem. The amount of C stored in the roots varied from 0 g C m-2 for plot BW, CP1, and CP2 to 2032.32 g C m-2 for plot NM3, and it accounted for less than 20% of C storage in the grassland.