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Feral swine (Sus scrofa) as an invasive species in the U.S. have caused severe damage to natural resources through competing for food resources with domestic livestock and destroying habitat by rooting and wallowing. Given their increased population and wide distribution in the southern U.S., feral swine control is becoming an urgent issue for both natural resource managers and landowners. We conducted a three-state mail survey to examine feral swine damage in Arkansas, Louisiana, and East Texas in the western gulf region in 2021. Our results reveal that feral swine activities like rooting and wallowing can cause severe and widespread damage to agriculture and forestry. Among the most reported and concerned damage by feral swine were crops, pastures, livestock, and loss of land value. Soybean damage was the most important agricultural crop damage in both Arkansas and Louisiana while it was hay, silage, and forage crops in East Texas. In terms of livestock damage, beef cattle and calves were the most common and severe damage in all three states. Average economic loss due to feral swine damage was estimated at $67.13/ha, $42.96/ha, $27.31/ha, and $57.54/ha for landowners in the region who owned cropland, forestland, pastureland, and multiple land types, respectively. Those findings could help both landowners and wildlife management personnel understand the negative societal impact of feral swine, and they could also facilitate the comparison between expected benefits and costs of control programs/options for feral swine in the southern states.

We analyzed the synchronized movements of lumber futures and southern pine sawtimber stumpage prices in the United States since 2011 and their response to COVID-19 events using wavelet analysis and event study. We found that the sawtimber and lumber prices have followed complex comovement patterns in the time–frequency domain and both reacted to COVID-19 events with a higher response intensity of the lumber price. Although they reacted differently to the early COVID-19 episodes and vaccine news, the sawtimber and lumber prices responded similarly to the COVID-19 pandemic declarations by the World Health Organization and US president, the US Food and Drug Administration panel’s recommendation of the first COVID-19 vaccine, and economic stimulus legislation. The patterns of synchronized movements between the sawtimber and lumber prices varied with time and frequency, but their comovement at low frequencies (>64 weeks) has strengthened since 2014 and been led by the lumber futures price; COVID-19 episodes have not changed this trend. The different magnitude of response of the two prices to the COVID-19-related events, as well as the long-term dominance of the lumber price in the comovement, reveals asymmetric price negotiation power and benefit distributions among the agents of the lumber value chain.

Sustainable forest management provides ecological, economic, and social benefits to society. Sustaining these benefits in Arkansas relies on 345,000 nonindustrial private forest (NIPF) landowners who own 4.2 million hectares (10.4 million acres) of forests. Forest certification is a voluntary and market-based mechanism aimed to enhance such societal benefits while providing incentives or benefits for the landowners. Understanding NIPF landowners’ perspectives on the benefits associated with adopting forest certification programs would be useful in identifying potential participants and in designing outreach and communication programs to elevate the interests of less interested landowners in participating in certification programs. Using data collected from a mixed mode of mail and online (Qualtrics) survey of NIPF landowners in Arkansas, this study examined the potential factors that influence landowners’ perspectives on different benefits associated with adopting sustainable forest management certification by employing binary logistic regression. Results revealed that ownership and forestland characteristics (i.e., ownership size, whether having a harvesting plan), as well as ownership motivations (biodiversity protection, financial investment, hunting), were significantly associated with landowners’ agreement on the benefits of increasing timber growth and health, expanding markets, having a price premium for certified timber, enhancing public recognition, more environmental-friendly harvesting, and better management practices. These findings improve the understanding of landowners’ expectations after certifying their forestland and provide baseline information for improving certification program design to attract more adoption among private and family landowners.

Bottomland hardwood forests (BHFs) offer a wide range of ecosystem services that are of high environmental and socioeconomic value. Yet, nearly 70% of BHFs in the southern United States have been lost during the past 100 years primarily due to land use change including agricultural expansion, calling for restoration efforts. We estimated the statistical relationship of the annual radial growth rate of three red oak species with climatic conditions and tree age using the tree ring data collected from a BHF plantation in the Arkansas Delta region. These species were Cherry bark oak (Quercus pagoda), Shumard oak (Quercus shumardii), and Nuttall oak (Quercus texana). The destructive sampling method was employed to obtain tree growth data and the cross-dating method was used for tree age determination. A log-linear regression model was estimated to uncover the statistical relationship between annual tree ring growth rate and climatic conditions. We identified the most critical time windows of climate variables that affect the growth of these trees. We found that the average temperature in October of the previous year and the minimum temperature between December of the previous year and January of the current year were positively associated with the radial growth rate in the current year although the maximum temperature from January to August and total precipitation from April to July of the current year were negatively correlated with the growth rate. Compared to Cherry bark and Shumard oaks, Nuttall oak was less sensitive to a rise in the minimum temperature between December and January. The projected climate change is likely to create slightly more favorable overall climatic conditions for these oak species in the region. Our findings suggest that these three red oak species are well suited for the study region for restoring BHFs, especially with a changing climate.

Inequities caused by a unilateral climate policy may threaten the sustainability of CO2 emission reduction efforts by countries and firms, thus endangering sustainable development for humans and the eco-environment. However, few studies have conducted ex-post evaluations on whether environmentally regulated firms receive external compensation such as subsidies, tax reductions, and loan support. Thus, this study investigates whether firms experiencing inequitable conditions under China’s Energy-Saving Quota Policy (ESQP) are financially compensated. It develops a balanced panel of data from 6189 ESQP-regulated and 6189 unregulated firms from 2010 to 2013, and combines a probit model with the difference-in-differences method to conduct empirical analysis. The results show that ESQP-regulated firms receive more subsidy income and lower tax rates than unregulated firms. Of the ESQP-regulated firms, companies with higher energy-saving burdens receive larger subsidies and lower financial expense ratios than those with lower burdens. Additionally, firms that complete their energy-saving quotas are compensated with larger subsidies and/or lower financial expense ratios and tax rates than those that fail to complete them. Finally, state-owned firms receive more subsidies than private ones. Unlike the emission trading schemes implemented worldwide that formulate an exemption mechanism (i.e., free or over-allocated allowances), the ESQP does not exempt regulated firms from their energy-saving responsibilities. Rather, regulated firms receive a greater amount of external compensation in exchange for their reductions in energy consumption.

Waste paper, an essential substitute for wood and other plant-based fibers in paper making, is an indispensable part of the circular economy; yet, the impacts of China's ban on global waste paper cycles have not been well understood. We modeled the evolution of the global waste paper trade network during 1995-2019. We found that the cumulative trade volume of global waste paper reached 1010 million tons in the last 25 years and showed a downward trend since 2015. The global import center of waste paper experienced a transfer from Europe to East Asia and then to Southeast Asia. The ban has stimulated some developed countries to reduce the exports of unsorted waste paper since 2017, but for many major importers their changes in waste paper trade patterns were related to waste paperboard, which was not banned by China, suggesting that this import change trend may be inevitable and irrespective of China's ban. Besides, India has replaced China to become a new import hub of unsorted waste paper. Our results lay a foundation for exploring the evolution of the future global solid waste cycle under the background of zero import of solid waste increasingly implemented by China and many other developing countries.

To assess the impacts of uncertainty and environmental objectives on the configuration of timber supply networks, we develop a generic multi-period, mixed-integer fuzzy linear programming model with demand uncertainty and two objectives of minimizing total transportation cost and greenhouse gas (GHG) emissions. We then use the triangular fuzzy number method to define the uncertain demands and convert the model into its equivalent auxiliary crisp counterpart. To derive Pareto solutions more efficiently, we propose the nondominated sorting genetic algorithm (NSGA-II) to solve the model. Finally, we apply the model framework and solution method to a real-world case of regional timber supply in Fujian, China, to demonstrate their applicability. The simulation results of the model show that trade-offs exist between total cost and GHG emissions and that the proper selection of the number and locations of distribution centers can help reduce both the cost and GHG emissions. Demand uncertainty and supply fluctuations across different time periods can increase the cost and GHG emissions. Our empirical results provide useful insights into the design and management of regional timber supply networks, and our generic model is applicable to the analysis of regional supply networks of other products or materials besides timber.

The scaled-up production of biofuels and bioproducts in the US is likely to cause land use expansion and intensification domestically and internationally, possibly leading to undesirable environmental and socioeconomic consequences. Although these concerns have been widely recognized, sustainability governance systems are yet to be developed. Here, we review (1) the US bioenergy policies, (2) biofuel production and market trends, (3) major sustainability concerns, and (4) existing regulations and programs for sustainability governance, including potential interactions with markets and technology. US bioenergy policy dates back to the 1970s and has evolved over time with various tax incentives plus production mandates in recent key legislation. Commercial production of cellulosic biofuels is impeded largely by technology and cost barriers. Uncertainties exist in the estimates of environmental and socioeconomic impacts due to the lack of empirical data and knowledge of complex relationships among biofuel and bioeconomic development, natural ecosystems, and socioeconomic dimensions. There are various existing sustainability governance mechanisms on which a biofuel sustainability governance system can be built on. Considering all these, we propose an adaptive system that incorporates regulations, certification, social norms, market, and technology for sustainability monitoring and governance, and is able to contribute to addressing the overall environmental concerns associated with collective land use for food, fiber, and fuel production. Building on existing programs and mechanisms and with proper monitoring of biofuel and bioproduct development, such a governing system can be developed and implemented in response to sustainability concerns that may arise as biofuel and bioproduct production increases.

The southern pine beetle (SPB), Dendroctonus frontalis Zimmermann, is one of the most destructive insects to pine forests in North and Central America. Historical SPB infestations have shown strong cyclical patterns and are attributed to an array of abiotic and biotic factors with climatic conditions being the dominant. Climate change has been projected to increase SPB infestations; however, its impacts on the cyclical patterns of SPB infestations remain unknown. Here, we estimated the statistical relationship between SPB infestations and climatic and other factors using generalized linear regression modeling and historical data, analyzed the cyclical patterns of SPB infestations via periodogram analysis and explored how these patterns would evolve with the projected future climate change in 11 states of the Southern United States. We found that SPB infestations intensified with increases in seasonal average temperatures and minimum winter temperatures and decreases in spring and winter precipitations. Compared to the historical SPB infestation patterns, climate change was estimated to nearly double SPB infestation frequencies although with smaller amplitudes in the region. Our findings advance the understanding of cyclical patterns of SPB infestations, especially climate change impacts on such patterns, aiding in developing and deploying future SPB management practices and strategies.

As the largest wood-based panel producing and exporting country, China has experienced sharp reductions in the growth rate of its wood-based panel exports because of pressure caused by exchange-rate fluctuation. These fluctuations were exacerbated by the global financial crisis. China’s wood-based panel exporters need to adjust their pricing strategy to cope with the changes of international market conditions. Thus, it is necessary to investigate the relationship between exchange-rate fluctuation and the pricing behavior of China’s wood-based panel exporters. To evaluate the impact of the exchange rate on China’s wood-based panel export prices across multiple destinations, a pricing-to-market model incorporating panel data was used. The empirical results suggest that although complete exchange-rate pass-through exists widely in China’s wood-based exports, China’s fiberboard and plywood exporters tended to adopt different pricing strategies in the international wood-based panel market during the post-crisis era. China’s fiberboard exporters often used the pricing-to-market model to determine prices in the main export destination countries, while China’s plywood exporters tended to amplify the exchange-rate effects. This indicates that China’s plywood exporters have stronger international market power than China’s fiberboard exporters, partly because China’s plywood exporters have more advantages in terms of skilled labor.

With the concern about environmental issues, supply chain designers and managers need to make trade-offs between the environmental impacts and costs of a logistics network. We develop a multi-objective optimization model that minimizes the total cost and CO2 emissions of a regional timber logistics network and seeks for the simultaneous optimization of logistics network design and operation. The generic model is applied to a case study in Jiangle County in China. The Pareto solution set, derived by applying the normalized normal constraint method, shows the relationship between carbon emissions and total cost. Our results reveal that both network structure and the allocations of timber flows have effects on the Pareto solutions, suggesting the importance of considering network design and management together in logistics network analysis. The model results also indicate that though the current carbon price is hard to trigger the change of the timber logistics network structure in Jiangle County, it...

Currently, > 20 million acres in the United States are protected through conservation easements. While the role of property rights in enabling conservation easements is well documented, attitudes of landowners living under those property rights regimes have not been thoroughly researched. To address the knowledge gap, landowners in Texas with perpetual conservation easements participated in a mail survey and resulting data were compared with prior research on the property rights perspectives of a group of noneasement-owning rural landowners. Our study indicates that easement and noneasement landowners differ in their attitudes concerning both property rights and social responsibilities with respect to land management. While landowners in both groups agreed that property ownership conveyed certain fundamental rights, noneasement landowners expressed stronger conventional property rights attitudes than easement landowners. Counter to expectations, noneasement landowners were also more likely to express a stronger land stewardship ethic. We also found significant demographic differences between the two groups with easement landowners tending to be younger, having more formal education, being less likely to live on their rural property and owning their property for a shorter period of time. Those demographic differences, combined with differences between the two groups of landowners with respect to dependence on their land for income, locational differences of the two surveys from which data were obtained, and the 9-yr span between the two surveys limited our ability to extrapolate our findings to a broader population of landowners. Intragroup comparisons among easement landowners failed to find differences between easement-granting and successive generation easement landowners with respect to property rights orientations, but we did find some attitudinal differences between male and female respondents. Our research implies that landowners willing to accept substantial property rights adjustments designed to facilitate environmental protection goals may have inherently different attitudes concerning property rights ideals.

Natural resource policies enacted to protect environmental integrity play an important role in promoting sustainability. However, when resources are shared ecologically, economically, or through a common, global interest, policies implemented to protect resource sustainability in one domain can displace, and in some cases magnify, environmental degradation to other domains. Although such displacement has been recognized as a fundamental challenge to environmental and conservation policy within some resource sectors, there has been little cross‐disciplinary and cross‐sectoral integration to address the problem. This suggests that siloed knowledge may be impeding widespread recognition of the ubiquity of displacement and the need for mitigation. Here, we connect research across multiple disciplines to promote a broader discussion and recognition of the processes and pathways that can lead to displaced impacts that countermand or undermine resource policy and outline a number of approaches that can mitigate displacement.

Several studies have highlighted that one of the largest risks with cellulosic biorefinery investments are year-to-year variability in cellulosic biomass quantity available. Yet, strategies to mitigate these risks in biofuel development are less understood. In the absence of strategies to minimize the impact due to these variations, both biorefineries and farmers venturing into the cellulosic biofuel arena will be significantly exposed. Studies have been done on using engineering approaches, such as biomass pre-treatment and storage to address biomass supply variations. Recent studies have provided market structure and contracting strategies to manage biomass supply risks. However, storage, pre-treatment and similar engineering approaches lead to higher costs and has other limitations such as additional infrastructural requirements. There is a gap in understanding the use of feedstock (biomass) diversification and portfolio strategies to mitigate such risks. In this study a portfolio approach is developed and applied to the case of the US Corn Belt, considering various types of cellulosic biomass including corn stover, wheat straw, and switchgrass. It is found that feedstock diversification mitigates up to 40% of feedstock supply variations, while biorefinery diversification can mitigate up to 70% of feedstock supply variations although it is constrained by current cropland use patterns in the region. Overall, diversification and portfolio strategies present an effective way for mitigating risks associated with feedstock supply variations. Keywords: Cellulosic biofuel, Diversification, MPT, Corn-stover

A comparative static Computable General Equilibrium model was used to assess the impacts of forest-based carbon payments on sequestration, land use, and agricultural commodity prices in the U.S. A modified 2008 regional Social Accounting Matrix, considering land as a heterogeneous factor, was used as the model's main input. The matrix was projected to its 2050 counterpart using capital and labour growth projections. The forest-generated carbon offset sources considered were afforested set-asides, commercial forestry intensification and harvested wood products. A new dataset on regional afforestation carbon uptake rates and costs was used to include afforested set-asides as latent activities. For a carbon offset price of $20/MT CO 2 , 12% of U.S. annual emissions could be sequestered in 2050. More than half of the additional carbon sequestered (611 million MT CO 2 ), compared to the 2050 baseline, would be attributed to set-asides and composed mainly of softwood forests. High carbon prices would increase land prices resulting in the diversion of 15% and 8% of pasture and cropland to carbon set-asides, respectively, mainly in the Central Plains. The high agricultural land diversion would force activities to intensify production systems driving the prices of beef up by 14% as well as oilseeds and grains by 3% and 4%, respectively.

Several federal- and state-sponsored programs, including cost-sharing arrangements, tax incentives, and technical assistance programs, are available to forestland owners, aiming to encourage desired forest management practices and outcomes. However, enrollment rates in such programs are low, and trends of forestland parcelization hint at an even smaller enrollment rate in the future. Therefore, it is important to understand how socioeconomic attributes of forestland owners and past experience with such programs affect the likelihood of enrollment in public incentive programs. Among others, this will help us provide tailored information to forestland owners who are less likely to use these opportunities through extension and outreach programs. Towards this end, we conducted a survey of 1800 forestland owners in Virginia and Texas. Our recursive partitioning, logistic regression, and Cochran–Armitage trend test results suggest that forestland owners who are less likely to enroll in such programs have relatively smaller forestland acreage, a lower level of education, and shorter land ownership tenure. We also find that forestland owners with experience in public incentive programs tend to attach higher importance to potential programs, including those that do not directly benefit them. We also identify threshold values for explanatory variables such as acreage and tenure length.

The availability of corn stover can vary considerably from year to year in a region due to annual changes in yield and area planted with corn. Such variations interacting with biomass market structures can affect biomass cost and utilization rate. This study first characterizes year-to-year variations in corn stover supply for the US in general and for selected major US corn producing counties in particular. There have been 20–30% year-to-year variations in stover supply in the US since 1975. Game theoretic analysis is then applied to examining corn stover utilization rate and production cost in three market structures. The analysis reveals that a free market structure will take the form of oligopoly–oligopsony, where large stover supply variations will expose both biorefineries and farmers to significant price volatility. Price equilibrium will shift significantly from year to year. Of the three market structures analysed, the “Derisked” supply market structure will be most favorable to biorefineries and farmers. Under this structure, biorefineries will maintain a stover supply region that is based on “Derisked” (lower than average) yield density to buffer for the supply uncertainty associated with annual variations. This market structure results in significantly less volatility in biomass cost while on average only 63% of collectable stover will be used for biofuel production. Our findings suggest that year-to-year variation in corn stover availability will increase feedstock cost and reduce its potential for biofuel production.

Biomass transport cost from field to a conversion facility is a major component of biofuel production cost. Several studies have provided a general framework, independent of location, for maximising cost competitiveness of bioenergy plants. The majority of these studies assume uniform spatial distribution of biomass and road network, independent of the size of the biorefinery. Although this assumption simplifies the theoretical derivation, it may not be suitable for practical cases. We develop a more generic biomass transport model that allows biomass yield density and road network vary with transport radius, and then derive a formula for determining biomass transport cost, which more accurately represents changes in biomass transport cost with conversion plant capacity. The formula can be used to evaluate locations and investment opportunities in large scale biofuel production.

Spatial spillover is widespread in forest product trade. We employ a spatial autoregressive (SAR) interaction model to analyze spatial spillover effects of global forest product trade in 2004 and 2014 and their underlying determinants. The SAR interaction model, specified with three types of spatial dependence (origin-to-origin, destination-to-destination and origin-to-destination) can account for the complex spatial interconnection of forest product trade, leading to unbiased and consistent estimates of effects of determinants on trade flows. Although all the spatial dependence parameters are statistically significant, the spatial interconnectivity was much stronger among destination countries than across origin countries. The identified spatial dependence reflects a core-periphery structure of the trade network. The effect decomposition shows that changes in the principal explanatory variables in the SAR interaction model had a greater total effect (TE) on trade flows in 2014 than in 2004. This attributes to a substantial increase of the origin effect (OE), destination effect (DE) and network effect (NE) from 2004 to 2014. Especially, NE rose by a big margin during this period and accounted for approximately 45% of TE in 2014 for each determinant. Based on the magnitude of NE that represents the spatial spillover effect, gross domestic product (GDP) ranked first, followed by gross national income (GNI) per capita, roundwood production per capita and tariffs. Besides the strong evidence of spatial spillover effects, we also find that countries tended to mimic their neighbors in forest product trade engagements. Our findings shed new light on the spatial interconnection of global forest product trade and offer implications for future trade and forest conservation policy design.

The Comprehensive Commercial Logging Ban in All Natural Forests (CCLB) policy, introduced in April 2015, aims to protect all natural forests in China. It has impacted both China&rsquo, s domestic timber supply and imports. We investigated price transmission in China&rsquo, s hardwood lumber imports resulting from the implementation of this policy. We selected three hardwood lumber species, i.e., Sapelli (Entandrophragma), Mandshurica (Fraxinus), and Laurel (Terminalia), and used their daily prices from 30 April 2015 to 30 November 2017. Threshold co-integration and threshold error correction models are employed for this analysis. We identified a structural breakpoint on 30 November 2016, and consequently partitioned the data series into two parts for the two subperiods separated by the breakpoint. The empirical results indicated that there was asymmetric price transmission (APT) for both subperiods. Adjustment of positive price deviations to the long-term equilibrium levels was slower than that of negative price deviations. In the short term, the price of high-quality lumber evolved independently, whereas the price of lower-quality lumber tended to return to the equilibrium. The APT reflects a redistribution of welfare, benefiting the exporters more than the importers. We find that positive discrepancies in each price pair were inclined to be more persistent in the first subperiod than in the second subperiod. This could attribute to the fact that the degree of CCLB intervention in the former one was higher than in the latter one.

This paper discusses biogas production in East Africa and the implications to household income and sustainable development. A household model that links livestock, biogas and crop production is analyzed. A base model was compared with three scenarios with an increase in crop yield from the use of bioslurry. The results demonstrated that investing in biogas plants only for energy replacement would not give farmers positive benefits at the current interest rates. The combined effects of lower interest and increases in yield could encourage farmers׳ investments in biogas plants that could lead to increases in household income and food security and reduction in deforestation in the region.

This study examines the statistical association of wildfire risk with climatic conditions and non-climate variables in 48 continental US states. Because the response variable “wildfire risk” is a fractional variable bounded between zero and one, we use a non-linear panel data model to recognize the bounded nature of the response variable. We estimate the non-linear panel data model (fractional probit) using the Generalized Estimating Equation (GEE) approach to ensure that the parameter estimation is efficient. The statistical model, coupled with the future climates projected by Global Climate Models (GCMs), is then employed to assess the impact of global climate change on wildfire risk. Our regression results show that wildfire risk is positively related to spring, summer, and winter temperatures and human population density whereas it is negatively associated with precipitation. The simulation results based on GCMs and the regression model indicate that climate change will intensify wildfire risk throughout the entire US, especially in the South Central region, posing an increasing wildfire threat and thus calling for more effective wildfire management strategies.

Wildfire has brought about ecological, economic, and social consequences that engender human responses in many parts of the world. How to respond to wildfire risk is a common challenge across the globe particularly in areas where lands are controlled by many small private owners because effective wildfire prevention and protection require coordinated efforts of neighboring stakeholders. We explore (i) wildfire response strategies adopted by family forestland owners in the southern United States, one of the most important and productive forest regions in the world, through a landowner survey; and (ii) linkages between the responses of these landowners and their characteristics via multinomial logistic regression. We find that landowners used diverse strategies to respond to wildfire risk, with the most popular responses being "doing nothing" and combined adaptation and mitigation, followed by adaptation or mitigation alone. Landowners who had lost properties to wildfire, lived on their forestlands, had a forest management plan, and were better educated were more likely to proactively respond to wildfire risk. Our results indicate the possibility to enhance the effectiveness of collective action of wildfire risk response by private forestland owners and to coordinate wildfire response with forest conservation and certification efforts. These findings shed new light on engaging private landowners in wildfire management in the study region and beyond.

This work considers a two-stage stochastic integer programming (SIP) approach for optimizing fuel treatment planning under uncertainty in weather and fire occurrence for rural forests. Given a set of areas for potentially performing fuel treatment, the problem is to decide the best treatment option for each area under uncertainty in future weather and fire occurrence. A two-stage SIP model is devised whose objective is to minimize the here-and-now cost of fuel treatment in the first-stage, plus the expected future costs due to uncertain impact from potential fires in the second-stage calculated as ecosystem services losses. The model considers four fuel treatment options: no treatment, mechanical thinning, prescribed fire, and grazing. Several constraints such as budgetary and labor constraints are included in the model and a standard fire behavior model is used to estimate some of the parameters of the model such as fuel levels at the beginning of the fire season. The SIP model was applied to data for a study area in East Texas with 15 treatment areas under different weather scenarios. The results of the study show, for example, that unless the expected ecosystem services values for an area outweigh fuel treatment costs, no treatment is the best choice for the area. Thus the valuation of the area together with the probability of fire occurrence and behavior strongly drive fuel treatment choices.

The mixed Cunninghamia lanceolata (Lamb.) Hook., Pinus massoniana Lamb., and hardwood forest in southeastern China is a major assemblage in natural secondary forests, and of national and international importance in terms of both timber and ecosystem services. However, over-harvesting has threatened its long-term sustainability, and there is a knowledge gap relating to the effect of harvesting on the ecosystem. After conifer species were selected for harvesting, the mixed Chinese fir, pine, and hardwood forest was changed into mixed evergreen broadleaf forest. In this context, we observed the restoration dynamics of plant communities over a period of 15 years (1996 to 2011) with different levels of harvesting intensity, including selective harvesting at low (13.0% removal of growing stock volume), medium (29.1%), high (45.8%), and extra-high (67.1%) intensities, as well as clear-cut harvesting (100.0%), with non-harvesting as the control, based on permanent sample plots established in a randomized block design in these forests in southeastern China. The impact on the richness, diversity, and evenness of plant species derived from descriptive statistical analyses was shown to initially increase, and then decrease, with an increase in harvesting intensity. The most critical impacts were on the richness, diversity, and evenness of shrub and herb species. Richness, diversity, and evenness of plant species recovered and increased under selective harvesting at low and medium intensities, while these parameters had not recovered and significantly decreased under selective harvesting at high and extra-high intensities, as well as with clear-cut harvesting. The impact on the plant community stability was derived from the stability test method of the improved Godron M. The plant community stability was closest to the point of stability (20/80) under selective harvesting at medium intensity, followed by selective harvesting at low intensity. The plant community stability was far from the point of stability (20/80) under selective harvesting at high and extra-high intensities, as well as with clear-cut harvesting. Of these treatments, clear-cut harvesting had the greatest effect with regard to reducing stability. Therefore, these results indicate that the selective harvesting at low and medium intensities is conducive to preserve or increase the species diversity and community stability. In order to prioritize promoting plant species diversity, clear-cut harvesting and selective harvesting at high and extra-high intensities should be avoided with regard to this type of forest in this region. This study sheds light on the practice of forest operation in the study region and subtropical forests with the same environment.

The economic and ecological damages caused by wildfires are alarming. Because such damages are expected to increase with changes in wildfire regimes, this calls for more effective wildfire mitigation and adaptation strategies. Wildfire adaptation options for forestland owners include purchasing wildfire insurance, which provides compensation to those insured if a wildfire damages their properties. We attempt to (i) identify factors that influence the decision of family forestland owners in the southern United States to purchase wildfire insurance for their forestlands via logistic regression using landowner survey data and (ii) examine the propensity of these landowners to purchase wildfire insurance under climate change. We find that landowners are much more likely to purchase wildfire insurance if they are female or well educated or if their land is not classed as heirs’ property, has been hit by a hurricane, or has not been burned by wildfire previously. Because climate change is likely to alter future wildfire and hurricane activity in the region, more forestland owners are predicted to purchase wildfire insurance, although the magnitude of such an increase appears moderate under current market institutions. These results would be helpful for developing new wildfire insurance programs and increasing the participation of forestland owners in the wildfire insurance market.

Illegal logging has negatively impacted environmental, economic, and social conditions in forests around the world. Various policies have been stymied owing to the complex web of timber harvesting, processing, manufacturing, and consumption cutting across developed and developing countries. We examine the potential impacts of new initiatives that directly address illegal timber trade by the two largest importers, primarily the ‘Lacy Act Amendment’ (LAA) by the US and the ‘Voluntary Partnership Agreements’ (VPAs) by the EU. We assess their effects on economy-wide welfare, prices of wood and paper products, and timber harvests in individual countries/regions and the world. We estimate that the LAA and VPAs, by themselves, would have moderate impacts on reducing illegal logging (0.1–8.35% reductions in timber harvests in the countries with high illegal logging rates). Broader cooperation among producer and consumer countries and alignment of existing forest governance mechanisms with illegal logging control measures are critical to create synergies.

US imports of wood and paper products from countries with emerging economies such as China and Brazil have dramatically increased in recent decades, partially displacing US domestic production. Such displacements may have reduced the direct production costs of these products, yet generated indirect economic and environmental impacts that are not well understood or taken into account. This study uses general equilibrium modeling to assess and compare the economy-wide impacts and greenhouse gas (GHG) consequences between US domestic production and imports from China and Brazil. Both the United States and China will benefit from enhancing US production of wood and paper products. In addition, strengthening the US wood products industries can help reduce GHG emissions and conserve tropical natural forests as China and Brazil import or use more tropical logs to produce wood products than the United States. These findings reveal the economic and environmental advantages of increasing US production of forest products, particularly wood products.

Removing excess biomass from fire-hazardous forests can serve dual purposes: enhancing the health and sustainability of forest ecosystems and supplying feedstock for energy production. The physical availability of this biomass is fairly well-known, yet availability does not necessarily translate into actual supply. We assess the perception and behavior of private forestland owners in the southern United States with respect to thinning overstocked forests for bioenergy production. Landowner perception is then integrated with the USDA Forest Service's Fuel Treatment Evaluator to estimate the biomass supply from fuel treatments on non-industrial private timberlands in the region. Due to competing uses for lumber and pulp/paper products, only about one-third of this biomass could be used as bioenergy feedstock. Between 6 and 66% of landowners would consider thinning overstocked forests for bioenergy purposes depending upon whether financial incentives and technical assistance are provided. Accounting for comp...

Various biomass sources can potentially be used for biofuel production, and many of these same biomass sources also have other uses. This raises an important question about biomass utilization allocation. We demonstrate an economic principle for biomass allocation by examining the profitability of woody biomass utilization in a simple two-product case. We then develop a mixed-integer programming model for allocating multiple biomass resources in the production of different biofuels and bioproducts. Our model combines biomass utilization allocation with biofuel supply chain optimization. The model is applied to solving the forest biomass utilization allocation problem for East Texas in the southern United States. We find that besides biofuel prices, production scale and CO2 offset credits also significantly affect biomass utilization allocation. Our findings validate our integrative model approach to addressing biomass allocation and provide useful implications for enhancing the efficient utilization of forest biomass. Keywords: forest biomass, biofuel supply chain, greenhouse gas offset, mathematical programming, southern United States. Received 10 October 2010, Revised 20 July 2012, Accepted 24 October 2012.

The difference in the shares of renewable energy in total primary energy supply among OECD countries is immense. We attempt to identify some key factors that may have driven this difference for renewable energy in general and bioenergy in particular. We found that besides country-specific factors, gross national product (GDP) and renewable energy and bioenergy market deployment policies have significant and positive impacts on the per capita supply of both renewable energy and bioenergy in OECD countries. R&D expenditures, energy prices, CO 2 emissions, and other energy policies are statistically insignificant in terms of their impact on renewable energy and bioenergy supply. However, this does not necessarily mean that they are not potential drivers for renewable energy and bioenergy, but rather suggests that their magnitudes have not been big enough to significantly influence energy supply based on the historical data from 1994 to 2003. These findings lead to useful policy implications for countries attempting to promote renewable energy and bioenergy development.

Bioenergy production involves a series of interrelated activities associated with feedstock production and feedstock-to-energy conversion. Thus, decisions on bioenergy production and deployment should be based on the simultaneous consideration of the entire supply chain. Based on cost minimization of both feedstock production and energy conversion, we develop a generic framework for determining the optimal bioenergy conversion plant size, the corresponding feedstock supply radius, and bioenergy production costs. The theoretical framework elucidates the relationships among activities along the bioenergy supply chain, suggesting strategies for enhancing the cost competitiveness of bioenergy. Such relationships as well as applications of our theoretical model are further illustrated using cases of producing electricity and cellulosic ethanol from biomass.

Aim We present an integrated approach for predicting future range expansion of an invasive species (Chinese tallow tree) that incorporates statistical forecasting and analytical techniques within a spatially explicit, agent-based, simulation framework. Location East Texas and Louisiana, USA. Methods We drew upon extensive field data from the US Forest Service and the US Geological Survey to calculate spread rate from 2003 to 2008 and to parameterize logistic regression models estimating habitat quality for Chinese tallow within individual habitat cells. We applied the regression analyses to represent population spread rate as a function of habitat quality, integrated this function into a logistic model representing local spread, and coupled this model with a dispersal model based on a lognormal kernel within the simulation framework. We simulated invasions beginning in 2003 based on several different dispersal velocities and compared the resulting spatial patterns to those observed in 2008 using cross Mantel’s tests. We then used the best dispersal velocity to predict range expansion to the year 2023. Results Chinese tallow invasion is more likely in low and flat areas adjacent to water bodies and roads, and less likely in mature forest stands and in pine plantations where artificial regeneration by planting seedlings is used. Forecasted invasions resulted in a distribution that extended from the Gulf Coast of Texas and Louisiana northward and westward as much as 300 km, representing approximately 1.58 million ha. Main conclusions Our new approach of calculating time series projections of annual range expansion should assist land managers and restoration practitioners plan proactive management strategies and treatments. Also, as field sampling continues on the national array of FIA plots, these new data can be incorporated easily into the present model, as well as being used to develop and/or improve models of other invasive plant species.

article i nfo The southeastern U.S. is one of the more wildland fire prone areas of the country and also contains some of the poorest or most socially vulnerable rural communities. Our project addresses wildland fire risk in this part of the U.S and its intersection with social vulnerability. We examine spatial association between high wildland fire prone areas which also rank high in social vulnerability ("hot spots") for Alabama, Arkansas, Florida, Georgia, Mississippi, and South Carolina. We also look at the proximity of hot spots to wildland fire mitigation programs. We hypothesize that hot spots are less likely than high wildland fire risk/low social vulnerability communities to engage with mitigation programs (e.g., Community Wildfire Protection Plans or Firewise Communities). To assess our hypothesis, we examined mean distances between: 1) hot spots and mitigation programs and 2) high wildland fire risk/low social vulnerability communities and mitigation programs. Overall, results show longer mean distances from hot spots to mitigation programs, compared to distances for high wildland fire risk/low social vulnerability communities. This finding provides support for our hypothesis and suggests that poorer communities in the southeast with high wildland fire risk may be at a greater disadvantage than more affluent, high fire risk communities in these states. Published by Elsevier B.V.

Soil nutrient loss is a major concern with removing forest residues for biofuel production. Understanding the impact of residue removal on site productivity via field experiment is costly and time consuming. We developed an analytical framework and a simulation approach for determining optimal forest residue removals, which account for both the benefits of biomass and greenhouse gas offset and the cost of soil productivity loss. We derived the relationship between residue removals and the prices of timber, biomass and greenhouse gases. The marginal cost of soil productivity loss associated with residue removals from loblolly pine (Pinus taeda L.) plantations in southern USA ranges from US$2.18 to 11.20/oven-dry tonne depending upon removal intensity. Given the cost of soil productivity loss, residue removal intensity will be much smaller than the quantity of biomass physically available.

Tropospheric ozone impacts the health and productivity of forest ecosystems. The concentration of ozone on Earth will increase in the future, particularly in China and its neighboring countries, including Korea, due to a projected rise in nitrogen dioxide and ozone precursors as a result of China’s emissions. This study aims to estimate the effect of changes in ozone concentration and climate change on the forests in Korea, based on expected nitrogen dioxide emissions in Korea and China in the future. To do this, we developed an empirical model that represents the statistical relationship between the net primary productivity (NPP) of the forests and ozone concentration using historical data; and, estimated the future NPP of the forests under future ozone concentration scenarios based on nitrogen dioxide emissions of the Shared Socioeconomic Pathway (SSP) scenarios. The analysis suggests that the ozone concentration begin exerting effects to the NPP, about 68.10 tC/km2/year decrement per 0.01 ppm increment. We estimated that the NPP of Korean forests has been reduced by 8.25% due to the current concentration of ozone, and the damage is estimated to increase to a range between 8.47% and 10.55% in the 2050s, and between 5.85% and 11.15% in the 2090s depending on the scenarios.

Production of forest biomass in sustainably managed forests in the southern United States has great potential to improve forest health, make energy supplies more secure, and increase the social and economic welfare of rural communities. The awareness and access of landowners and forestry and natural resource professionals to new knowledge and market development opportunities must be increased, and new technological advances in knowledge dissemination systems can be very useful in this connection. The Encyclopedia of Southern Bioenergy was developed within The Forest Encyclopedia Network (www.forestencyclopedia.net/) to facilitate the transfer of useable knowledge from scientific experts in bioenergy and bio-based products to natural resource professionals, landowners, and the general public. Using the encyclopedia as a base, a team of bioenergy and extension education experts has developed several new educational products. These materials are designed as components of an overall biomass training program for the South that is being disseminated through the Southern Regional Extension Forest network.