Aboveground Carbon Storage Research Articles

Factors influencing early secondary succession and ecosystem carbon stocks in Brazilian Atlantic Forest

Ecologically relevant restoration of secondary Atlantic forest on abandoned land offers a potential means to recover biodiversity and improve crucial ecosystem services, including carbon sequestration. Early secondary successional trajectories are determined by a range of environmental factors that influence plant community development. Context-specific understanding of forest vegetation communities, their dynamics, and underlying drivers is needed for future restoration strategies. In this study we examined relationships between soil (chemical and physical) and environmental (landscape and topographical) characteristics, plant community attributes, and carbon stocks during early secondary succession. Data were collected at two sites undergoing early secondary succession in seasonally-dry Atlantic Forest (Rio de Janeiro State, Brazil). Both sites were previously used for pasture and abandoned at similar times, but showed differing vegetation communities. We found tree biomass and diversity and ecosystem carbon storage to be strongly positively related to the amount of surrounding forest, less steep slopes and clay soils, and negatively to the abundance of the shrub Leandra aurea. Soil carbon pools significantly increased with aboveground tree biomass. The only factor significantly affecting the metric of overall successional development (combining tree biomass and diversity) was total surrounding forest cover. Our findings suggest recovery of secondary forest and below- and aboveground carbon storage is limited by the amount of adjacent forest, some soil properties and dense shrub establishment down-regulating the succession process. Overall we offer evidence of potential to improve recovery of Atlantic forest with ecologically relevant seeding/planting programmes and selective shrub removal that could benefit ecosystem carbon storage.

Effects of historical and current disturbance on forest biomass in Minnesota

Context Historical carbon storage prior to widespread forest clearing is uncertain. We examined aboveground biomass in historical (1847–1908) and current (2004–2008) mixed and broadleaf forests of Minnesota. Objective Our objective was to compare aboveground forest biomass density and total aboveground carbon storage for two forest types with different historical and current disturbance regimes. Methods We used densities and diameter distributions from historical and current tree surveys and applied relationships between diameter and biomass to estimate biomass in historical and current forests for larger trees with diameters C12.7 cm. Results In the 8.5 million ha Northern Mixed Forest ecological division of Minnesota, historical forests ecosystems under a stand-replacing fire regime that produced high density forests contained greater aboveground biomass density (98 Mg/ha) than current forests (53 Mg/ha) disturbed by frequent tree cutting. Historical total carbon storage was 333 TgC and current carbon storage was 158 TgC; estimates depended on diameter distribution and historical forested extent. In the 4.5 million ha Eastern Broadleaf Forest division, historical forests under a frequent surface fire regime that produced low density oak savannas contained less biomass density (54 Mg/ha) than current dense eastern broadleaf forests (93 Mg/ha). Historical total carbon storage was 79 TgC and current carbon storage was 31 TgC, depending on diameter distribution and forested extent. Conclusions Total carbon storage appears to be unrealized due to potential for tree diameter increases in both divisions, stem density increases in the Northern Mixed Forest, and forested extent increases in the Eastern Broadleaf Forest.

The relative importance of climate, stand variables and liana abundance for carbon storage in tropical forests

AbstractAimTo develop an integrative framework to evaluate variation in aboveground carbon storage (AGC). A model that can be applied to understand and predict how global‐change drivers influence tropical carbon sinks.LocationOld‐growth tropical forests world‐wide.MethodsUsing structural equation modelling (SEM), we propose an a priori model to evaluate the direct and indirect effects of climate, stand variables (basal area, tree diameter and wood density at plot level) and liana abundance onAGC. Our model indicated that stand variables increasedAGCwhile liana abundance decreasedAGCindirectly via negative effects on stand variables. We used a multigroupSEMto test the generality of our framework using a standardized dataset of 145 plots (0.1 ha) in dry, moist and wet tropical forests.ResultsOur model explained over 85% variation inAGCand showed a positive and consistent relationship between stand variables andAGCacross forests types. The effects of climate onAGCwere indirect rather than direct, with negative effects of temperature in all forests. Liana abundance reduced tree diameter and basal area in moist forests, but did not affectAGCin wet or dry forests.Main conclusionsOur results suggest that climate affectsAGCindirectly, via its direct influence on stand variables and liana abundance. The effects of lianas onAGCresult from reductions in stand variables and are as important as climate for moist forests, which harbour the greatest tropical carbon pools. Our model was consistent across forest types. This highlights the usefulness of an integrative framework to improve predictions of the effects of drivers of global change on tropical carbon sinks.

Comparing aboveground structure and aboveground carbon storage of an age series of moso bamboo forests subjected to different management strategies

The purpose of this study was to compare aboveground carbon storage capacities of different management strategies of an age series of moso bamboo (Phyllostachys pubescens) forests. The study site was located in the lower mountain area of central Taiwan. Stand structure and aboveground carbon storage were compared between moso bamboo stands that were subjected to two management strategies, intensive management (IM) and extensive management (EM). The Chi squared (χ2) test was utilized to examine the frequency distribution of culms among the age classes in each stand. All the IM stands passed the χ2 test, while only 41.7 % of the EM stands passed the test. This result suggests that the IM stands contain culms that are homogeneously distributed within an age series, while more than one-half of the EM stands did not follow this distribution. In addition, the relative root mean square errors (RRMSEs) of carbon storage in the age classes were calculated as an indicator of the variations of carbon storage in the age classes of each stand. A non-parametric test (Wilcoxon Scores) was utilized to compare the RRMSEs of the IM and EM stands; the results indicated that the RRMSEs were significantly different between these two management strategies. The IE stands displayed a smaller RRMSE than the EM stands, suggesting that the IE stands had stable carbon storage in the age series.

The impact of selective logging and clearcutting on forest structure, tree diversity and above‐ground biomass of African tropical forests

AbstractTropical deforestation is well known to have serious negative consequences for biodiversity, terrestrial carbon sinks and the balance of atmospheric greenhouse gases. By contrast, selective logging of tropical forests is often regarded as having a lesser impact on the ecosystem particularly in long terms, even though there have been few critical evaluations of the practice, particularly in Africa. We compared field data from 511 plots in the tropical forest of Sierra Leone, Ghana, Cameroon and Gabon. These plots were subject to different forest management practices: no recent logging (primary forests), selective logging (up to 30 years old) and re‐grown secondary forests post clear‐cutting (at least 20 years ago). Our findings suggest that the vertical structure and plant richness of the selectively logged and secondary forests change in different amplitude from those of primary forests, but stem density and the prevalence of vine and weed species differ greatly. We show that the effects of selective logging are greater than those expected simply from the removal of commercial species, and can persist for decades. Selective logging, unless it is practiced at very low harvest intensities, can significantly reduce the biomass of a tropical forest for many decades, seriously diminishing aboveground carbon storage capacity, and create opportunities for weeds and vines to spread and slow down the ecological succession.

Relationships between tree species richness, evenness and aboveground carbon storage in montane forests and miombo woodlands of Tanzania

Understanding how carbon storage and tree diversity are related in forests and woodlands is crucial for a sustainable flow of ecosystem goods and services. The goal of this study was to determine how tree species richness, evenness and environmental factors influence aboveground live tree carbon stocks (AGC) in two tropical vegetation types in Tanzania. We surveyed trees and sampled soil from 222 vegetation plots (20m×40m) in montane forests (n=60) and miombo woodlands (n=162). We used a multimodel inference approach to determine how AGC related to tree species richness, evenness and environmental factors, and linear mixed effect models to test the role of tree sizes on the AGC-richness and evenness associations. AGC were related unimodally to tree species richness and evenness in the montane forest. Likewise, AGC in the miombo woodlands was positively related to tree species richness. AGC from small trees were related unimodally to tree species richness in both vegetation types. Apparently the AGC had both monotonically increasing and decreasing associations with all abiotic environmental factors in both vegetation types. We emphasize that both tree size, number of multi-stemed trees and environmental factors have an important role in determining how AGC are related to richness and evenness. Finally, management of montane forests and miombo woodlands of Tanzania to enhance ecosystem benefit, such as AGC, will require strategies that consider tree sizes, tree species richness, evenness and underlying environmental and disturbance factors.

Prospects of photon counting lidar for savanna ecosystem structural studies

Abstract. Discrete return and waveform lidar have demonstrated a capability to measure vegetation height and the associated structural attributes such as aboveground biomass and carbon storage. Since discrete return lidar (DRL) is mainly suitable for small scale studies and the only existing spaceborne lidar sensor (ICESat-GLAS) has been decommissioned, the current question is what the future holds in terms of large scale lidar remote sensing studies. The earliest planned future spaceborne lidar mission is ICESat-2, which will use a photon counting technique. To pre-validate the capability of this mission for studying three dimensional vegetation structure in savannas, we assessed the potential of the measurement approach to estimate canopy height in a typical savanna landscape. We used data from the Multiple Altimeter Beam Experimental Lidar (MABEL), an airborne photon counting lidar sensor developed by NASA Goddard. MABEL fires laser pulses in the green (532 nm) and near infrared (1064 nm) bands at a nominal repetition rate of 10 kHz and records the travel time of individual photons that are reflected back to the sensor. The photons’ time of arrival and the instrument’s GPS positions and Inertial Measurement Unit (IMU) orientation are used to calculate the distance the light travelled and hence the elevation of the surface below. A few transects flown over the Tejon ranch conservancy in Kern County, California, USA were used for this work. For each transect we extracted the data from one near infrared channel that had the highest number of photons. We segmented each transect into 50 m, 25 m and 10 m long blocks and aggregated the photons in each block into a histogram based on their elevation values. We then used an expansion window algorithm to identify cut off points where the cumulative density of photons from the highest elevation resembles the canopy top and likewise where such cumulative density from the lowest elevation resembles mean ground elevation. These cut off points were compared to DRL derived canopy and mean ground elevations. The correlation between MABEL and DRL derived metrics ranged from R2 = 0.70, RMSE = 7.9 m to R2 = 0.83, RMSE = 2.9 m. Overall, the results were better when analysis was done at smaller block sizes, mainly due to the large variability of terrain relief associated with increased block size. However, the increase in accuracy was more dramatic when block size was reduced from 50 m to 25 m than it was from 25 m to 10 m. Our work has demonstrated the capability of photon counting lidar to estimate canopy height in savannas at MABEL's signal and noise levels. However, analysis of the Advanced Topography Laser Altimeter System (ATLAS) sensor on ICESat-2 indicate that signal photons will be substantially lower than those of MABEL while sensor noise will vary as a function of solar illumination, altitude and declination, as well as the topographic and reflectance properties of surfaces. Therefore, there are reasons to believe that the actual data from ICESat-2 will give poorer results due to a lower sampling rate and use of only the green wavelength. Further analysis using simulated ATLAS data are required before more definitive results are possible, and these analyses are ongoing.

Estimation of biomass and carbon storage of tree plantations in northern Iran

To estimate the aboveground biomass and carbon storage in multi-species plantations we used species-specific equations method and three other generic methods. Astara county is located in northern Iran. It has a total area of 1,757 ha. Based on species-specific allometric equations, total aboveground biomass was calculated andvaried between 81.13 and 98.21 t·ha<sup>–1 </sup>for Acer velutinum, 68.36 and 83.44 t·ha<sup>–1</sup> for Quercus castanifolia, 71.88 and 119.22 t·ha<sup>–1</sup> for Tilia begonifolia, 56.07 and 61.98 t·ha<sup>–1</sup> for Fraxinus excelsior and from 37.92 to 51.34 t·ha<sup>–1</sup> for Prunus avium. There was a significant difference between the mean values of total aboveground biomass estimation obtained by species-specific equations and the three generic methods for Alnus subcordata, Pinus taeda and Pinus nigra. Results indicated that using generalized methods produced more reliable and accurate estimations for native species than for exotic species for rapid biomass and carbon estimation in order to decide on plantation development in the area.

Mapping carbon storage in urban trees with multi-source remote sensing data: Relationships between biomass, land use, and demographics in Boston neighborhoods

High resolution maps of urban vegetation and biomass are powerful tools for policy-makers and community groups seeking to reduce rates of urban runoff, moderate urban heat island effects, and mitigate the effects of greenhouse gas emissions. We developed a very high resolution map of urban tree biomass, assessed the scale sensitivities in biomass estimation, compared our results with lower resolution estimates, and explored the demographic relationships in biomass distribution across the City of Boston. We integrated remote sensing data (including LiDAR-based tree height estimates) and field-based observations to map canopy cover and aboveground tree carbon storage at ~1m spatial scale. Mean tree canopy cover was estimated to be 25.5±1.5% and carbon storage was 355Gg (28.8MgCha−1) for the City of Boston. Tree biomass was highest in forest patches (110.7MgCha−1), but residential (32.8MgCha−1) and developed open (23.5MgCha−1) land uses also contained relatively high carbon stocks. In contrast with previous studies, we did not find significant correlations between tree biomass and the demographic characteristics of Boston neighborhoods, including income, education, race, or population density. The proportion of households that rent was negatively correlated with urban tree biomass (R2=0.26, p=0.04) and correlated with Priority Planting Index values (R2=0.55, p=0.001), potentially reflecting differences in land management among rented and owner-occupied residential properties. We compared our very high resolution biomass map to lower resolution biomass products from other sources and found that those products consistently underestimated biomass within urban areas. This underestimation became more severe as spatial resolution decreased. This research demonstrates that 1) urban areas contain considerable tree carbon stocks; 2) canopy cover and biomass may not be related to the demographic characteristics of Boston neighborhoods; and 3) that recent advances in high resolution remote sensing have the potential to improve the characterization and management of urban vegetation.

Effects of land-use changes on woody species distribution and above-ground carbon storage of forest-coffee systems

As deforestation and fragmentation continue in tropical regions with high human use and disturbance of natural habitats, production landscapes such as agroforests and plantations may provide some forest-based services depending on tree selection, agroforest management and intensification. This is typical to southwest Ethiopia with strong human-dependence on forest biodiversity and ecosystem services. We examined the effects of land-use changes and fragmentation on woody species distribution and the relative importance of forest fragments and coffee farms in wood use and carbon storage. We sampled heartwood from 71 woody species in three land use types: natural forest fragments, smallholder semi-forest coffee farms and state-owned coffee plantations. We calculated wood density as an oven-dry biomass per fresh volume of heartwood core samples, and above-ground carbon biomass using allometric methods. We found that average wood density values were not correlated with fragment size. Mean wood density of species in forests was greater than in state-owned plantations. The two coffee systems can store 50–62% of the above-ground carbon biomass found in forests, indicating the need to incorporate coffee farms and forest remnants in carbon incentive, or climate mitigation and adaptation programs. To correlate species wood density with local wood preferences, we interviewed focus groups and households about the use-values of 51 farmer-appreciated species. There was a strong correlation between wood density and local wood-values signifying the concordance of species functional traits and ecosystem service values. Our results indicate the need to integrate functional traits and local ecosystem service uses in climate adaptation and mitigation by incorporating coffee agroforests with the conservation of natural forest remnants.

Non-additive effects of mixing hybrid poplar and white spruce on aboveground and soil carbon storage in boreal plantations

The use of trees under intensive management is particularly important for rapid fiber production in boreal regions. Mixed-species plantations using species that have complementary ecological niches, such as hybrid poplar and white spruce, potentially can maximize the use of resources and, consequently, increase productivity. In the context of climate change, vegetation and soil carbon sequestration is of a particular interest as part of a possible means of compensating for CO2 emissions. Since higher productivity leads to higher CO2 sequestration, the use of mixed-species plantations could improve the ecological service of carbon storage compared to mono-specific plantations. We compared above-ground and soil C storage of nine-year-old mono-specific plantations of white spruce and hybrid poplar with mixed plantations of these two species. Soil carbon was evaluated by separately sampling four soil horizons, while aboveground carbon was assessed from tree biomass estimates using allometric relationships. Mixing white spruce and hybrid poplar exerted a substantial synergistic effect on above-ground and soil carbon storage. This positive effect was due to greater productivity of poplar (47% of biomass increase) and great accumulation of litter in soil surface horizons (52% L-horizon carbon increase) of mixed-species compared to mono-specific plantations. These results imply that in addition to wood production gains by poplar trees, mixed-species plantations of hybrid poplar and white spruce promotes greater carbon sequestration than mono-specific plantations of either hybrid poplar or white spruce, an important aspect of forest ecosystem services.

Modeling canopy height in a savanna ecosystem using spaceborne lidar waveforms

Although savanna ecosystems cover about 20% of the terrestrial land surface and can have productivity equal to some closed forests, their role in the global carbon cycle is poorly understood. As a result, these ecosystems are globally more important than generally appreciated in the earth observation and modeling communities. Remote sensing has been proposed as an efficient tool in assessing the physical structure of an ecosystem which in turn is closely related to its ecological functionality such as carbon storage. Studies using Light Detection and Ranging (lidar) have demonstrated the technology's ability to measure canopy height and the strong relationship between canopy height and structural attributes such as aboveground biomass, but most of this work has focused on closed canopy forests. This study explored the applicability of spaceborne lidar to estimate canopy height as a pre-requisite for aboveground biomass and carbon storage assessment in savannas. The research used a case study of the Oak Savannas of Santa Clara in California, USA. Discrete return airborne lidar data was used to extract height metrics in plots coincident with waveform data from the Ice Cloud and land Elevation Satellite (ICESat)'s Geoscience Laser Altimeter System (GLAS). Detailed analysis of GLAS waveforms was followed by non-parametric regression modeling to estimate maximum canopy height and 80th and 90th percentile vegetation heights. Existing methods were adapted with the inclusion of NDVI (as a canopy cover proxy) and interaction terms to increase utility in savanna ecosystems. Our main findings were that merely adopting the methods derived for forests would not produce adequate results. Maximum canopy height was estimated with better accuracy compared to percentile height metrics. The inclusion of NDVI and interaction terms improved maximum canopy height modeling much more than it did for the 80th and 90th percentile height modeling. Taller stands on flat terrain had the best results while shorter stands on steep terrain had the worst. Our work has demonstrated the capability of waveform lidar to assess vegetation structural attributes in savannas. The challenge in canopy height modeling using this technique in such ecosystems not only is limited to terrain slope but also includes the interacting influence of low canopy cover and short height. As such, we need special models for savanna areas in an effort to do global assessments of terrestrial vegetation structure using lidar. For future studies we recommend a closer look at the non-significant influence of canopy cover on the percentile canopy height models especially its implication on the subsequent biomass modeling.

110Years of change in urban tree stocks and associated carbon storage.

Understanding the long-term dynamics of urban vegetation is essential in determining trends in the provision of key resources for biodiversity and ecosystem services and improving their management. Such studies are, however, extremely scarce due to the lack of suitable historical data. We use repeat historical photographs from the 1900s, 1950s, and 2010 to assess general trends in the quantity and size distributions of the tree stock in urban Sheffield and resultant aboveground carbon storage. Total tree numbers declined by a third from the 1900s to the 1950s, but increased by approximately 50% from the 1900s–2010, and by 100% from the 1950s–2010. Aboveground carbon storage in urban tree stocks had doubled by 2010 from the levels present in the 1900s and 1950s. The initial decrease occurred at a time when national and regional tree stocks were static and are likely to be driven by rebuilding following bombing of the urban area during the Second World War and by urban expansion. In 2010, trees greater than 10 m in height comprised just 8% of those present. The increases in total tree numbers are thus largely driven by smaller trees and are likely to be associated with urban tree planting programmes. Changes in tree stocks were not constant across the urban area but varied with the current intensity of urbanization. Increases from 1900 to 2010 in total tree stocks, and smaller sized trees, tended to be greatest in the most intensely urbanized areas. In contrast, the increases in the largest trees were more marked in areas with the most green space. These findings emphasize the importance of preserving larger fragments of urban green space to protect the oldest and largest trees that contribute disproportionately to carbon storage and other ecosystem services. Maintaining positive trends in urban tree stocks and associated ecosystem service provision will require continued investment in urban tree planting programmes in combination with additional measures, such as revisions to tree preservation orders, to increase the retention of such trees as they mature.

Assessing urban tree carbon storage and sequestration in Bolzano, Italy

Recent climate change, environmental design, and ecological conservation policies require new and existing urban developments to mitigate and offset carbon dioxide emissions and for cities to become carbon neutral. Some North American models and tools are available and can be used to quantify the carbon offset function of urban trees. But, little information on urban tree carbon storage and sequestration exists from the European Southern Alps. Also, the use of these North American models in Europe has never been assessed. This study developed a protocol to quantify aboveground carbon (C) storage and sequestration using a subsample of urban trees in Bolzano, Italy, and assessed two existing and available C estimation models. Carbon storage and sequestration were estimated using city-specific dendrometrics and allometric biomass equations primarily from Europe and two other United States models; the UFORE (Urban Forest Effects Model) and the CUFR Tree Carbon Calculator (CTCC). The UFORE model carbon storage estimates were the lowest while the CUFR Tree Carbon Calculator (CTCC) C sequestration estimates were the highest. Results from this study can be used to plan, design, and manage urban forests in northern Italy to maximize C offset potential, provide ecosystem services, and for developing carbon neutral policies. Findings can also be used to predict greenhouse gas emissions from tree maintenance operations as well as estimating green waste yield from landscape maintenance activities and its use as biofuel and compost. Managers need to be aware that available models and methods can produce statistically different C storage and sequestration estimates.

Overstory and Understory Dynamics in a Ponderosa Pine Plantation Vary with Stand Density in the Sierra Nevada: 40-Year Results

We periodically measured overstory ponderosa pine (Pinus ponderosa) growth and understory cover and abundance in a long-term study on the west slope of the Sierra Nevada, California, USA. The study was established in 1969 in a 20-year-old plantation, thinned to basal areas of 9, 16, 23, 30, and 37 m2 ha−1 and rethinned three times. The objective was to determine the effect of stand density regimes on productivity, understory vegetation, aboveground carbon storage, and mortality caused mainly by Dendroctonus infestations. Results showed that without mortality, basal area and volume increments were not affected by thinning the plantation to 16 m2 ha−1 from 37 m2 ha−1. With Dendroctonus actively attacking trees, the plantation could be thinned to 9 m2 ha−1 without sacrificing volume increment, because the level of mortality increased with stand density index. The thinning intensity did not affect the abundance of understory vegetation but did affect the cover of understory trees and graminoids. Intensively managed plantations could sequester and store the same amount of carbon as less intensively managed plantations. However, because fire is a major component in a pine-dominant ecosystem, carbon in larger diameter trees would be more resilient to wildfire than carbon in small diameter trees or understory vegetation.

Aboveground Carbon Storage and Its Spatial Distribution in the Subalpine Forest of Daofu County Based on Remote Sensing Model

Based on the TM image data in September 2007 and investigation results of the field biomass of 45 sampling plots,this research established a remote sensing estimation model to assess the biomass of coniferous forest,broad-leaved forest,and shrubbery,and to estimate the carbon storage of the subalpine forest in Muru forest farm,Daofu County,western Sichuan in China.The result showed that the total carbon storage of forest vegetation in the study region was 1.73 TgC,the average carbon density was 70.55 t hm-2.Coniferous forest,with carbon storage of 1.26 TgC,was the primary component of forest carbon pool in the region,accounting for 72.83% of the regional total carbon storage.The total carbon storage changed with elevation,being the highest at the elevation of 3 400-3 800 m and diminishing with higher or lower altitudes.It also varied with the slope as abrupt slope slope steep slope gentle slope flat slope dangerous slope.In terms of the slope aspect,the total carbon storage presented the order of shady half-sunny half-shady sunny flat.There was no obvious relationship among vegetation carbon density,altitude gradient and aspect.The vegetation carbon density increased with slope gradient,mainly due to the fewer disturbances,longer time for vegetation growth,and larger biomass.

Assessment of carbon stores in tree biomass for two management scenarios in Russia

Accurate quantification of terrestrial carbon storage and its change is of key importance to improved understanding of global carbon dynamics. Forest management influences carbon sequestration and release patterns, and gap models are well suited for evaluating carbon storage. An individual-based gap model of forest dynamics, FAREAST, is applied across Russia to estimate aboveground carbon storage under management scenarios. Current biomass from inventoried forests across Russia is compared to model-based estimates and potential levels of biomass are estimated for a set of simplified forestry practices. Current carbon storage in eastern Russia was lower than for the northwest and south, and lower than model estimates likely due to high rates of disturbance. Model-derived carbon storage in all regions was not significantly different between the simulated ‘current’ and hypothetical ‘even-aged’ management strategies using rotations of 150 and 210 years. Simulations allowing natural maturation and harvest after 150 years show a significant increase in aboveground carbon in all regions. However, it is unlikely that forests would be left unharvested to 150 years of age to attain this condition. These applications indicate the value of stand simulators, applied over broad regions such as Russia, as tools to evaluate the effect of management regimes on aboveground carbon storage.

Mapping potential carbon and timber losses from hurricanes using a decision tree and ecosystem services driver model

Information on the effect of direct drivers such as hurricanes on ecosystem services is relevant to landowners and policy makers due to predicted effects from climate change. We identified forest damage risk zones due to hurricanes and estimated the potential loss of 2 key ecosystem services: aboveground carbon storage and timber volume. Using land cover, plot-level forest inventory data, the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model, and a decision tree-based framework; we determined potential damage to subtropical forests from hurricanes in the Lower Suwannee River (LS) and Pensacola Bay (PB) watersheds in Florida, US. We used biophysical factors identified in previous studies as being influential in forest damage in our decision tree and hurricane wind risk maps. Results show that 31% and 0.5% of the total aboveground carbon storage in the LS and PB, respectively was located in high forest damage risk (HR) zones. Overall 15% and 0.7% of the total timber net volume in the LS and PB, respectively, was in HR zones. This model can also be used for identifying timber salvage areas, developing ecosystem service provision and management scenarios, and assessing the effect of other drivers on ecosystem services and goods.

Management trade‐off between aboveground carbon storage and understory plant species richness in temperate forests

Because forest ecosystems have the capacity to store large quantities of carbon (C), there is interest in managing forests to mitigate elevated CO2 concentrations and associated effects on the global climate. However, some mitigation techniques may contrast with management strategies for other goals, such as maintaining and restoring biodiversity. Forest thinning reduces C storage in the overstory and recruitment of detrital C. These C stores can affect environmental conditions and resource availability in the understory, driving patterns in the distribution of early and late-seral species. We examined the effects of replicated (N = 7) thinning experiments on aboveground C and understory vascular plant species richness, and we contrasted relationships between aboveground C and early- vs. late-seral species richness. Finally, we used structural equation modeling (SEM) to examine relationships among early- and late-seral species richness and live and detrital aboveground C stores. Six years following thinning, aboveground C was greater in the high-density treatment and untreated control than in moderate- (MD) and variable-density (VD) treatments as a result of reductions in live overstory C. In contrast, all thinning treatments increased species richness relative to controls. Between the growing seasons of years 6 and 11 following treatments, the live overstory C increment tended to increase with residual density, while richness decreased in MD and VD treatments. The richness of early-seral species was negatively related to aboveground C in MD and VD, while late-seral species richness was positively (albeit weakly) related to aboveground C. Structural equation modeling analysis revealed strong negative effects of live overstory C on early-seral species richness balanced against weaker positive effects on late-seral species richness, as well as positive effects of detrital C stocks. A trade-off between carbon and plant species richness thus emerges as a net result of these relationships among species traits, thinning treatments, and live and detrital C storage. Integrating C storage with traditional conservation objectives may require managing this trade-off within stands and landscapes (e.g., maintain early-seral habitat and species within dense, C-rich forests and, conversely, live and detrital C stores in early-seral habitats) or separating these goals across scales and species groupings.

KANDUNGAN KARBON DI HUTAN RAWA GAMBUT KAWASAN KONSERVASI PT NATIONAL SAGO PRIMA, KEPULAUAN MERANTI, RIAU

This study was conducted to collect information regarding carbon storage, particularly the carbon stored in the aboveground biomass as well as in the peat soil. The study site was in a conservation area of the PT National Sago Prima belonging to the PT Sampoerna Agro Tbk. Group. The work was undertaken in January-February 2012. The total aboveground biomass and carbon storage in the research site indicates that the conservation area is a secondary peat swamp forest, with the biomass of 149.18 ton/ha and carbon stock of 70.12 ton C/ha. The aboveground biomass and carbon consisted of biomass and carbon of tree (83.97 ton/ha containing 39.47 ton C/ha, respectively), saplings (20.69 ton/ha containing 9.72 ton C/ha) and seedlings and undergrowth plants (0.03 ton/ha containing 0.01 ton C/ha), wood necromass (24.06 ton/ha containing 11.31 ton C/ha), and litter (20.44 ton/ha containing 9.61 ton C/ha). An allometric equation was developed for Pandanus atrocarpus Griff . providing an estimated total biomass and carbon of 5.16 ton/ha containing 2.42 ton C/ha. The underground C with the mean peat depth of 5.5 m, mean bulk density of 0.18 g/cm 3 , and the mean organic C of 46.6 % was 464.895,94 ton C/ha. In the entire conservation forest area of 541 ha the total aboveground biomassa and carbon storage was estimated to be 80,708.64 ton and 37,934.00 ton C, while the total underground carbon was 238,96 million MT C.