Logistics of supplying biomass from a mountain pine beetle-infested forest to a power plant in British Columbia

Abstract

The search for alternative energy sources has increased the interest in forest biomass. During the past few years, the severe infestation of the mountain pine beetle (MPB) within the forests of interior British Columbia (BC) has led to huge volumes of dead wood that exceed the capacity of the lumber industry. One way to make the most value of the surplus wood is to use it as the feedstock for bioenergy. The high costs associated with harvest and transport, and uncertainty in supply logistics are issues related to forest biomass utilization. This paper presents the development of a forest biomass supply logistics simulation model and its application to a case of supplying MPB-killed biomass from Quesnel timber supply area (one of the most infested areas in the interior BC) to a potential 300 MW power plant adjacent to the city of Quesnel. It provides values of quantity, cost and moisture content of biomass which are important factors in feasibility study of bioenergy projects. In the case of a conventional harvesting system, the biomass recovered from roadside residues in 1 year will meet only about 30% of the annual demand of the power plant with an estimated delivered cost of Can $45 per oven-dry tonne of woodchips. Sensitivity analyses were also performed.     

Cost analysis of a satellite terminal for forest fuel supply in Finland

As forest fuel demand increases, new logistical solutions are needed. Most of the increase in use is expected to take place in large heat and power production units which set special requirements for the supply as both procurement volumes and transport distances increase. Biomass fuel terminals broaden the spectrum of available supply options by offering cost-effective large-scale biomass storage and processing options for securing the fuel supply in all conditions. This study aimed to study different costs of a satellite terminal and to produce important concept and cost information for developing forest fuel logistics based on future terminals. The figures indicate that terminals do not create direct cost benefits per se: direct supply chains are more economical compared to supply through terminals. However, there are several indirect benefits that can be reached via fuel supply through terminals: regional fuel procurement can be widened to a national scale, security of supply increases through easily available storages, large supply volumes can be delivered by an individual operator, prices remain more stable and a more even quality of delivered fuel can be achieved.     

Cost structure of and competition for forest-based biomass

Abstract

Biomass has become a popular alternative to satisfy expanding energy demand and as a substitute for fossil fuels and phased-out nuclear energy in Europe. The European Union White Paper stipulates that the utilization of biomass shall increase to 1566 TWh by 2010. However it is often overlooked that the forest resources are already, to a large extent, used by the forest industries. When promoting biomass for energy generation the consequences for the forest industries also need to be considered. Sweden is an excellent case study, as there are vast quantities of forest resources, nuclear power is starting to be phased out, there are restrictions on expanding hydropower and the political desire exists to “set an example” with respect to carbon dioxide emissions. This paper attempts to estimate and analyse the supply of two types of forest resource, namely, roundwood and harvesting residues derived from final harvesting and commercial thinnings. Two separate supply curves are estimated: one for roundwood and one for harvesting residues. The cost structure is based on an economic-engineering approach where the separate cost components are constructed from the lowest cost element into aggregates for labour, capital, materials and overhead costs for each forest resource. The results indicate an unutilized economic supply of 12 TWh of harvesting residues in Sweden. However, after these 12 TWh have been recovered it becomes more profitable to use roundwood for energy purposes than to continue extracting further amounts of harvesting residues.     

Estimates of forest biomass in the Brazilian Amazon: New allometric equations and adjustments to biomass from wood-volume inventories

Uncertainties in biomass estimates in Amazonian forests result in a broad range of possible magnitude for the emissions of carbon from deforestation and other land-use changes. This paper presents biomass equations developed from trees directly weighed in open forest on fertile soils in the southern Amazon (SA) and allometric equations for bole-volume estimates of trees in both dense and open forests. The equations were used to improve the commonly used biomass models based on large-scale wood-volume inventories carried out in Amazonian forest. The biomass estimates from the SA allometric equation indicate that equations developed in forests on infertile soils in central Amazonia (CA) result in overestimates if applied to trees in the open forests of SA. All aboveground components of 267 trees in open forests of SA were cut and weighed, and the proportion of the biomass stored in the crowns of trees in open forest was found to be higher than in dense forest. In the case of inventoried wood volume, corrections were applied for indentations and hollow trunks and it was determined that no adjustment is needed for the form factor used in the RadamBrasil volume formula. New values are suggested for use in models to convert wood volume to biomass estimates. A biomass map for Brazilian Amazonia was produced from 2702 plots inventoried by the RadamBrasil Project incorporating all corrections for wood density and wood volume and in factors used to add the bole volume of small trees and the crown biomass. Considering all adjustments, the biomass map indicates total biomass of 123.1 Gt (1 Gt = 1 billion tons) dry weight (aboveground + belowground) for originally forested areas in 1976 in the Brazilian Legal Amazon as a whole (102.3 Gt for aboveground only) at the time of the RadamBrasil inventories, which were carried out before intensive deforestation had occurred in the region. Excluded from this estimate are 529,000 km² of forest lacking sufficient RadamBrasil inventory data. After forest losses of 676,000 km² by 2006 – not counting 175,000 km² of this deforested area lacking RadamBrasil data – the estimated dry biomass stock was reduced to 105.4 and 87.6 Gt (aboveground + belowground and only above-ground). Thus, in 2006 the carbon storage in forested areas in Brazilian Amazonia as a whole will be around 51.1 Gt (assuming 1 Mg dry biomass = 0.485 Mg C). Biomass estimates by forest type (aggregated into 12 vegetation classes) are provided for each state in the Brazilian Legal Amazon.     

Improving the estimate of forest biomass carbon storage by combining two forest inventory systems

Quantifying forest carbon storage and its spatial distribution at regional scales is critical for the creation of greenhouse gases inventories, the evaluation of forest services and carbon-oriented forest management. The plot-based forest inventory (PBFI) and stand-based forest inventory (SBFI) collect extensive information on trees and stands respectively, and together, provide an opportunity to improve the regional estimates of forest carbon. In this study, we applied the SBFI to overcome the spatial extent limits of the PBFI in neighboring plots and improve the regional carbon estimation. We found that the forests in Sichuan Province reserved a total of 624.2?Tg?C in biomass and featured a large spatial heterogeneity, with high values in natural forests and low values in plantations. We found that the solo use of PBFI derived a slightly higher (46.63?Mg?C/ha) estimation on average compared with the integrated method (43.6?Mg?C/ha). However, when considering the spatial distribution, the PBFI generated an overestimation of young forests located between 3000and 4000?m in elevation, and an underestimation in mature forests. The spatially explicit biomass carbon estimation could be helpful in guiding regional forest management and biodiversity conservation.     

Long-term response of living forest biomass to extensive logging in subtropical China

Forest disturbance and recovery are critical ecosystem processes,but the temporal patterns of disturbance have not been studied in subtropical China.Using a tree-ring analysis approach,we studied post-logging above-ground(ABG)biomass recovery dynamics over a 26-year period in four plots with different degrees of logging disturbance.Before logging,the ABG biomass ranged from 291 to 309 t ha-1.Soon after logging,the plots in primary forest,secondary forest,mixed forest and singlespecies forest had lost 33,91,90 and 100%of their initial ABG biomass,respectively.Twenty-six years after logging,the plots had regained 147,62,80 and 92%of their original ABG biomass,respectively.Over the 26 years following logging,the mean CAI(Current annual increment)were 10.1,5.5,6.4 and 10.8 t ha^-1 a^-1 and the average MAI(Mean annual increment)8.7,2.5,5.6 and 7.8 t ha^-1 a^-1 for the four forest types,respectively.The results indicate that subtropical forests subjected to moderate logging or disturbances do not require intensive management and single-species plantings can rapidly restore the above-ground biomass to levels prior to heavy logging.     

Spatial limitations in forest biomass harvesting using Geographic Information System and Remote Sensing for an ecological and sustainable bioenergy framework

As the sustainable forest biomass harvesting process is highly influenced by the terrain, the heterogeneity, and the protection status of the landscape, this study highlights the GIS and Remote Sensing as important scientific tools, assisting in the planning process and integrating the appropriate spatial limitations for an ecological forest biomass extraction in a rational bioenergy utilization framework. This study is focused on the northwest Greece and particularly in the regional unit of Grevena which is part of the Western Macedonia region, the region with the highest unemployment rates in Greece. As the forests in the regional unit of Grevena occupy a significant percentage over half of the regional unit area, the emphasis on the sustainable harvesting and utilization of forest biomass for energy purposes could tackle unemployment rates, enhance the energy autonomy of the remote mountain villages, and reduce the Mediterranean forest fire risk. The spatial data process and the implied spatial limitations unfold a methodology procedure, which is revealing specifically quantified and illustrated results as are emerging progressively the oak forests of the regional unit of Grevena with biomass harvesting capabilities, which do not belong to the Grevena’s protected areas, have accessible slopes and lower diversity index.     

Simulation of the biomass dynamics of Masson pine forest under different management

Introduction Masson pine (Pinus massoniana) is important both economically and ecologically in subtropical mountainous areas in China, and it is vital not only as an important source of commercially harvested timber and charcoal fuel, but also as a pionee…     

SWOT analyses and SWOT strategy formulation for forest owner cooperations in Austria

Forest owner cooperations (FOC) are bundling wood supply from small-scale forests and some also offer additional services, such as wood harvesting or planting. FOCs are growing throughout Europe in terms of the managed timber volume. The increasing timber demand of forest-based industries as well as the new, rapidly growing demand for energy plants could lead to an under-supply in the following years in Europe. Because of high harvesting arrears in small-scale forests, FOCs are seen as an opportunity to overcome this foreseen timber shortage. The paper maps out timber mobilisation strategies using the SWOT (Strengths, Weaknesses, Opportunities and Threats) approach.

Values placed on forest property benefits by Swedish NIPF owners: Differences between members in forest owner associations and non-members

A forest property represents benefits to the owner, the nature of which varies between resident and non-resident owners. Forest owners’ associations can be considered as an arrangement to increase the benefit from forest ownership by helping the forest owner to increase profitability. Thus, it can be assumed that associated forest owners value forest property benefits differently to non-associated owners. This study examines differences between members and non-members, and residents and non-residents, with respect to how they value the various forest property benefits. Responses from a landholder survey reveal differences concerning forestry income, maintaining contact with native locality, and keeping up a tradition in forestry. It is concluded that a challenge for the associations is to develop the organisation in accordance with the forest owners’ dissimilar property interests.     

A non-destructive method for estimating above-ground forest biomass in threatened woodlands

Current techniques for calculation of biomass in agroforestry require felling of many trees. Such methods are not well suited to the natural environment, especially if the environment is subject to anthropic degradation and if the wood supply to local populations is at stake. The method we describe here was used in a socioeconomic and ecological study of the biomass of a thuriferous juniper woodland (Juniperus thurifera L.) in the High Central Atlas mountains (Morocco). This computerized method reconstructs the different component volumes of a tree from two orthogonal-view photographs. Then, using the volume and the density of each component, it estimates the biomass of the tree. Regression curves were established between dendrometric parameters for 102 trees (tree height × crown projection area) and their estimated biomass by this computer method. A second-order polynomial equation gave the best regressions with a high coefficient of determination (R² = 0.96). To validate the method, the biomass of seven trees (cut in a previous study) was compared with those obtained from our regression equations, while in a second study, the biomass of three trees, estimated from photographs using the computer program, was compared with values obtained after felling and weighing the same trees.

The results show that the method is reliable with a mean error percentage varying between 2.5 and 7.5 per tree. For young trees, the accuracy of the biomass could be improved, for example, by using a tree morphology classification.     

Forest natural regeneration and biomass production after slash and burn in a seasonally dry forest in the Southern Brazilian Amazon

This study estimates the aboveground biomass accumulation after forest clearing and slash burning and describes the structure and successional development of the secondary forest in the seasonally dry southern Amazon. The original burn study was conducted in four land clearings in 1997, 1998, and 1999. The size of the clearings varied from 1 to 9 ha. The native forest was felled, allowed to dry for approximately three months and then burned by the end of the dry season. A census was conducted in the central 1-ha forest on each site prior to the area's felling and burn. The aboveground biomass (AGB) and structure were similar to other primary tropical forests. However, the high density of Cecropia spp. before the forest felling and burn treatment indicates past low intensity disturbances. Seven and eight years after the fire, the fallow forests were still in an early successional stage dominated by Cecropia spp. The four areas had a high biomass accumulation during the studied period, varying from 7.5 to 15.0 Mg ha⁻¹ year⁻¹. The lower biomass accumulation in one plot was an effect of a higher fire severity, produced by the one-year difference in time between slash and burn of the forest, slowing the natural regeneration of Cecropia spp. The time needed for this forest to recover to the pre-fire AGB levels ranged from 20 to 30 years, assuming the current AGB accumulation rates are maintained. Considering these results, the maintenance of regenerating secondary forests in the Amazon would be a significant contribution to soil and watershed protection, minimizing biodiversity losses and perhaps mitigating climatic changes effects in the region.     

遥感在森林生物量监测的应用

森林生物量研究对监测生态系统有着重要作用,随着遥感技术的发展,动态地估测大区域乃至全球的森林生物量成为可能.文章就遥感数据源和估测方法,分析总结了传统方法和遥感方法的森林生物量估测.     

Estimations of total ecosystem carbon pools distribution and carbon biomass current annual increment of a moist tropical forest

With increasing CO₂ in the atmosphere, there is an urgent need of reliable estimates of biomass and carbon pools in tropical forests, most especially in Africa where there is a serious lack of data. Information on current annual increment (CAI) of carbon biomass resulting from direct field measurements is crucial in this context, to know how forest ecosystems will affect the carbon cycle and also to validate eddy covariance flux measurements. Biomass data were collected from 25 plots of 13 ha spread over the different vegetation types and land uses of a moist evergreen forest of 772,066 ha in Cameroon. With site-specific allometric equations, we estimated biomass and aboveground and belowground carbon pools. We used GIS technology to develop a carbon biomass map of our study area. The CAI was estimated using the growth rates obtained from tree rings analysis. The carbon biomass was on average 264 ± 48 Mg ha⁻¹. This estimate includes aboveground carbon, root carbon and soil organic carbon down to 30 cm depth. This value varied from 231 ± 45 Mg ha⁻¹ of carbon in Agro-Forests to 283 ± 51 Mg ha⁻¹ of carbon in Managed Forests and to 278 ± 56 Mg ha⁻¹ of carbon in National Park. The carbon CAI varied from 2.54 ± 0.65 Mg ha⁻¹ year⁻¹ in Agro-Forests to 2.79 ± 0.72 Mg ha⁻¹ year⁻¹ in Managed Forests and to 2.85 ± 0.72 Mg ha⁻¹ year⁻¹ in National Park. This study provides estimates of biomass, carbon pools and CAI of carbon biomass from a forest landscape in Cameroon as well as an appropriate methodology to estimate these components and the related uncertainty.     

Greenhouse gas balance of harvesting stumps and logging residues for energy in Sweden

Abstract

In this case study, forest fuel procurement chains of stumps and logging residues were evaluated using a Life Cycle Assessment perspective. Direct emissions from combustion were not included, but soil organic carbon change was included as changes in carbon stocks in litter and soil. The results showed that primary forest biomass for energy has a climate impact which is time dependent. However, in long-time perspectives, there are large greenhouse gas (GHG) savings. In a short-term (20 years), there were no GHG savings when natural gas or coal was replaced. This is due to the fact that the harvest lead to decreased input of organic matter to the soil which is compared to a reference where biomass are left to decompose. The reduction in soil organic carbon may have been underestimated in the stump harvest systems studied, as the effect of soil disturbance per se was not included. Important factors when assessing GHG balance of forest fuels, besides the time horizon used, were site productivity, geographical position and forest fuel resource (stumps or logging residues). When assessing the greenhouse gas savings, efficiency of the end-use, allocation method between heat and power and type of fossil fuel replaced were also important.     

Determination of elements removal in different harvesting scenarios of Scots pine (Pinus sylvestris L.) stands

Increasing demand for renewable energy and limiting CO₂ emissions have stimulated much interest in wood-based biofuels. Unfortunately, expanding the utilization of forest biomass may cause nutrient depletion in forested environments. This study investigates the element content from various parts of the tree. Comparisons were made between different harvesting scenarios and their impact on the amount of nutrients removed from the forest environment. The harvesting scenarios were: stem-only harvesting (SOH), branch and stem harvesting (BSH), and two variants of whole-tree harvesting (WTH). The elements taken into account were: carbon (C), nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sodium (Na), sulphur (S), copper (Cu), iron (Fe), nickel (Ni), manganese (Mn), zinc (Zn), cadmium (Cd), chromium (Cr) and lead (Pb). To make the results comparable, the same amount of removed biomass was taken into calculation. The differences between harvesting scenarios were significant. The amounts of removed elements formed similar pattern: the lowest level was found in SOH, average in BSH, and highest in both variants of WTH. This confirms that the application of WTH is connected with increased risk of nutrient depletion, even when the volume of harvest would be equal to other variants.     

Feasibility of a harvesting system for logging residues as unutilized forest biomass

The concept of a “harvesting system for unutilized forest biomass by a processor and a forwarder” is examined for the purpose of constructing a system to harvest logging residues (or slashes) as a new resource for energy. The rate of slash harvesting, α, and the energy input rate of hauling slashes,p (%), are defined as indices of the possibility of harvesting slashes and the utilization of slashes for energy, respectively. From an analysis of the field experiment, both the volume of logs hauled by the forwarder per day,E _F (m³/day), andp are expressed as functions of the hauling distance,L(m). The productivity of the processor,E _P (m³/day), andL were used to calculate α. Results showed that α was approximately 0.95 for the experiment site, indicating that almost all the slashes could be hauled. It was recognized that the energy utilization of slashes was feasible for this site becausep was less than 1 %. The hauling cost per unit weight of slashes was calculated as 15.4 yen/kg on an oven-dry weight basis. This high cost clarified that the cost must be reduced by taking measures such as enhancing the hauling efficiency of the forwarder. A part of this paper was orally presented at the 5th Annual Meeting of the Japan Forest Engineering Society (1998).     

Spatial partitioning of biomass and diversity in a lowland Bolivian forest: Linking field and remote sensing measurements

Large-scale inventories of forest biomass and structure are necessary for both understanding carbon dynamics and conserving biodiversity. High-resolution satellite imagery is starting to enable structural analysis of tropical forests over large areas, but we lack an understanding of how tropical forest biomass links to remote sensing. We quantified the spatial distribution of biomass and tree species diversity over 4 ha in a Bolivian lowland moist tropical forest, and then linked our field measurements to high-resolution Quickbird satellite imagery. Our field measurements showed that emergent and canopy dominant trees, being those directly visible from nadir remote sensors, comprised the highest diversity of tree species, represented 86% of all tree species found in our study plots, and contained the majority of forest biomass. Emergent trees obscured 1–15 trees with trunk diameters (at 1.3 m, diameter at breast height (DBH)) ≥20 cm, thus hiding 30–50% of forest biomass from nadir viewing. Allometric equations were developed to link remotely visible crown features to stand parameters, showing that the maximum tree crown length explains 50–70% of the individual tree biomass. We then developed correction equations to derive aboveground forest biomass, basal area, and tree density from tree crowns visible to nadir satellites. We applied an automated tree crown delineation procedure to a high-resolution panchromatic Quickbird image of our study area, which showed promise for identification of forest biomass at community scales, but which also highlighted the difficulties of remotely sensing forest structure at the individual tree level.     

Seedling biomass allocation and vital rates of cloud forest tree species: Responses to light in shade house conditions

Patterns of above- and below-ground biomass allocation in seedlings of nine common cloud forest (CF) tree species of western Mexico were examined under varying controlled light conditions using artificial shade houses. We analysed the relationships between vital rates (growth and survival) and four morphological traits (SLA, biomass allocation to stems, leaves and roots). We hypothesised that these traits represent differentiation axes in the way seedlings face the heterogeneous light regime typical of the CF understorey. For all species, traits between the different light levels, i.e. allocation to leaves, roots and stems differed among light levels. Five species had the largest SLA in the lowest light levels at the end of the experiment (Citharexylum, Dendropanax, Fraxinus, Quercus and Magnolia). Juglans was the only species with a large SLA at the highest light level (377.47 cm² g⁻¹). In contrast, light levels did not cause any significant variation in SLA of Persea and Simplococarpon at the end of the experiment. The relative height growth rates (RHGR) of the seedlings of five species were significantly different between light levels (P < 0.05). Overall, all species grew better in the highest light levels. The RHGR of three species were correlated positively with SLA. In turn, allocation to stem, leaves and root biomass were strongly correlated with the RHGR of five species (e.g. Citharexylum, Dendropanax and Fraxinus). Survival did not vary significantly between treatments in any species, only in the case of Simplococarpon (P < 0.05) and was correlated with all morphological variables. For this species, Peto and Peto's test showed a significantly larger survival of seedlings in the highest light level. The mean responses of these species based on all traits to the controlled light variation did not differed significantly. Our results show that these species display a wide range of resource allocation patterns when exposed to the varying light conditions that may be found in the forest understorey and highlight the role of morphological traits in this variation.     

Future quantities and spatial distribution of harvesting residue and dead wood from natural disturbances in Canada

Interest in the use of bioenergy is increasing because of the need to mitigate climate change, the increasing costs and finite supply of fossil fuels, and the declining price of lumber and paper. Sound bioenergy policies must be informed by accurate estimates of potential feedstock production, rights to the production, social values and economics. Two of the main sources of bioenergy feedstock from forests are (i) harvesting residue and (ii) dead wood resulting from natural disturbances (i.e. standing dead timber). We modeled the production of bioenergy feedstock from these two sources from 2005 to 2020 for Canada's managed forest south of 60° N so that this information can be used in provincial and national strategic planning. Published estimates of harvesting residue vary widely, and our objective was to provide more precise estimates based on new forest inventory data and regional modeling. Natural disturbances result in very large quantities of dead wood on the landscape, but estimates of future stocks and annual production have not previously been made. Our estimates included a 50% discount factor to net-down theoretically available quantities to a more realistic estimate of potential ecologically sustainable bioenergy feedstock. The total future annual production averaged 51 ± 17 Tg year⁻¹ from natural disturbances and 20 ± 0.6 Tg year⁻¹ from clearcut harvesting residues. Harvesting residue for the area logged varied spatially from a low of 1.0 ± 0.77 kg m⁻² year⁻¹ to a high of 6.7 ± 0.1 kg m⁻² year⁻¹. Dead wood production due to insects was forecast to peak in the Montane Cordillera of British Columbia (BC) at 16.7 Tg year⁻¹ due to the current mountain pine beetle outbreak. Total dead wood production due to fire was highest in the western portion of the boreal forest (3.6 Tg year⁻¹ in the Boreal Shield of Saskatchewan), in part due to the high frequency of fires in these ecosystems and the large area of western boreal forest, but the highest density production was in BC: >9 kg m⁻² year⁻¹ in the burned area. Our results showed that the dead wood stocks of 331 Tg oven-dry matter potentially available for bioenergy in 2020 are much smaller than the 3100 ± 84 Tg of dead wood stocks estimated based on ecosystem dynamics. While bioenergy use will accelerate the release of greenhouse gases compared to on-site decay, the energy is renewable and can be used as a substitute for fossil fuels. The net benefit to the atmosphere of forest bioenergy use is affected by many factors, and future research should further assess which sustainable wood-based bioenergy strategies yield the greatest net greenhouse gas benefits over the different time scales needed for post-disturbance forest recovery.