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We assessed the net impacts of a wood-dependent pellet industry of global importance on contemporaneous local forest carbon component pools (live trees, standing-dead trees, soils) and total stocks. We conducted post-matched difference-in-differences analyses of forest inventory data between 2000 and 2019 to infer industrial concurrent and lagged effects in the US coastal southeast. Results point to contemporaneous carbon neutrality. We found net incremental effects on carbon pools within live trees, and no net effects on standing-dead tree nor soil pools. However, we found concurrent lower carbon levels in soils, mixed effects associated with increased procurement pressures and large mill pelletization capacity, and possible spillover effects on standing-dead tree carbon pools beyond commercial procurement distances. There is robust evidence that although some trade-offs between carbon pools exist, the wood pellet industry in this particular context and period has met the overall condition of forest carbon neutrality.

Individual behavior is influenced by factors intrinsic to the decision-maker but also associated with other individuals and their ownerships with such relationship intensified by geographic proximity. The land management literature is scarce in the spatially integrated analysis of biophysical and socio-economic data. Localized land management decisions are likely driven by spatially-explicit but often unobserved resource conditions, influenced by an individual's own characteristics, proximal lands and fellow owners. This study examined stated choices over the management of family-owned forests as an example of a resource that captures strong pecuniary and non-pecuniary values with identifiable decision makers. An autoregressive model controlled for spatially autocorrelated willingness-to-harvest (WTH) responses using a sample of residential and absentee family forest owners from the U.S. State of Missouri. WTH responses were largely explained by affective, cognitive and experience variables including timber production objectives and past harvest experience. Demographic variables, including income and age, were associated with WTH and helped define socially-proximal groups. The group of closest identity was comprised of resident males over 55 years of age with annual income of at least $50,000. Spatially-explicit models showed that indirect impacts, capturing spillover associations, on average accounted for 14% of total marginal impacts among statistically significant explanatory variables. We argue that not all proximal family forest owners are equal and owners-in-absentia have discernible differences in WTH preferences with important implications for public policy and future research.

Demand for tropical timber is expected to rise due to an increased global need for sustainable renewable materials. However, sustainable tropical timber production remains a challenge for the global wood product supply chain, especially for high-value tropical hardwoods. Restoration of degraded lands through enrichment planting of native hardwood species could provide a solution, but the financial viability of using native tropical tree species remains largely unknown. We evaluated the financial viability of 22 hardwood tree species native to northern Borneo in enrichment plantings of a degraded forest in Sabah, Malaysia. We investigated how the species’ financial value, expressed as an internal rate of return (IRR) based on land expectation value, varied with their functional trait composition. We found that high financial value was positively correlated with trait values associated with a conservative growth strategy, i.e., financial value was negatively correlated with leaf calcium, magnesium, and nitrogen content, as well as with leaf pH and specific leaf area. Trees with these traits showed a high IRR, partly explained by relatively fast growth and high survival rates. For the most economically promising species, Shorea macrophylla, we estimated that enrichment planting for forest restoration could reach IRRs up to 7.8%. Our results showed that enrichment planting for high-value hardwood production in degraded forests can be financially viable, with variation among species, and that various traits associated with a more conservative growth strategy were linked to high financial value.

Water scarcity poses one of the most prominent threats to the well-being of smallholder farmers around the world. We studied the association between rural livelihood capitals (natural, human, social, financial, and physical) and resilience to water scarcity. Resilience was denoted by farmers’ self-reported capacity to have avoided, or adapted to, water scarcity. Proxies for livelihood capitals were collected from two-hundred farmers in South Sulawesi, Indonesia, and their associations with a typology denoting water scarcity impacts analyzed with a Taylor-linearized multinomial response model. Physical and natural assets in the form of irrigation infrastructure and direct access to water sources were saliently associated with overall resilience (avoidance and adaptation) to water scarcity. Years of farming experience as a form of human capital asset was also strongly associated with resilience to water scarcity. Factors solely associated with the capacity to adapt to water scarcity were more nuanced with social capital assets showing closer associations. A household with a larger number of farm laborers had a higher likelihood of being unable to withstand water scarcity, but this relationship was reversed among those who managed larger farming areas. We discuss possible mechanisms that could have contributed to resilience, and how public policy could support smallholder farmers cope with water scarcity.

Implementation of the European Union Renewable Energy Directive has triggered exponential growth in trading of pelletized wood fibers. Over 18 million tons of wood pellets were traded by EU member countries in 2018 of which a third were imported from the US. Concerns exist about negative impacts on US forests but systematic assessments are currently lacking. We assessed variability in fundamental attributes for timberland structure and carbon stocks within 123 procurement landscapes of wood pellet mills derived from over 38 thousand forest inventory plots in the eastern US from 2005 to 2017. We found more carbon stocks in live trees, but a fewer number of standing-dead trees, associated with the annual operation of large-scale wood pellet mills. In the US coastal southeast—where US pellet exports to the EU originate—there were fewer live and growing-stock trees and less carbon in soils with every year of milling operation than in the rest of the eastern US—which supplies the domestic market. Greater overlap of mills’ procurement areas exhibited discernible increments across selected carbon stocks. These trends likely reflect more intensive land management practices. Localized forest impacts associated with the wood pellet industry should continue to be monitored.

Secondary tropical forests are at the forefront of deforestation pressures. They store large amounts of carbon, which, if compensated for to avoid net emissions associated with conversion to non-forest uses, may help advance tropical forest conservation. We measured above- and below-ground carbon stocks down to 1 m soil depth across a secondary forest and in oil palm plantations in Malaysia. We calculated net carbon losses when converting secondary forests to oil palm plantations and estimated payments to avoid net emissions arising from land conversion to a 22-year oil palm rotation, based on land opportunity costs per hectare. We explored how estimates would vary between forests by also extracting carbon stock data for primary forest from the literature. When tree and soil carbon was accounted for, payments of US$18–51 tCO 2 –1 for secondary forests and US$14–40 tCO 2 –1 for primary forest would equal opportunity costs associated with oil palm plantations per hectare. If detailed assessments of soil carbon were not accounted for, payments to offset opportunity costs would need to be considerably higher for secondary forests (US$28–80 tCO 2 –1 ). These results show that assessment of carbon stocks down to 1 m soil depth in tropical forests can substantially influence the estimated value of avoided-emission payments.

Biopower, electricity generated from biomass, is a major source of renewable energy in the US. About ten percent of US non-hydro renewable electricity in 2020 was generated from biomass. Despite significant growth in woody biomass use for electricity in recent decades, a systematic assessment of associated impacts on forest resources is lacking. This study assessed associations between biopower generation, and selected timberland structure indicators and carbon stocks across 438 areas surrounding wood-using and coal-burning power plants in the Eastern US from 2005 to 2017. Timberland areas around plants generating biopower were associated with more live and standing-dead trees, and carbon in their respective stocks, than comparable areas of neighboring plants only burning coal. We also detected an inverse association between the number of biopower plants and number of live and dead trees, and respective carbon stocks. We discerned an upward temporal trajectory in carbon stocks within live trees with continued biopower generation. We found no significant differences related to the amount of MWh biopower generation within the analysis areas. Net impacts of biopower descriptors on timberland attributes point to a positive trend in selected ecological conditions and carbon balances. The upward temporal trend in carbon stocks with longer generation of wood-based biopower may point to a plausibly sustainable contribution to the decarbonization of the US electricity sector.

Grassland environments face a number of threats including land use change, changing climate and encroachment of woody plants. In the Southern Plains of the United States, woody plant encroachment threatens traditional agricultural grazing economies in addition to grassland dependent wildlife species. Numerous studies have examined the physical drivers of conversion from grassland to woodland but social drivers may be equally important to understanding the causes of and prescriptions for environmental degradation. In this paper, we report the results of a survey of landowners in the Southern Plains of Texas and Oklahoma in which we asked participants to estimate the current amount of woody plant cover on their land, their preferred amount of woody plant cover and about their perspectives regarding the use of prescribed fire for managing woody plants. Prescribed fire is ecologically and economically one of the most effective tools for maintaining grasslands but many landowners do not use this tool due to lack of knowledge, lack of resources and concerns over safety and legal liability. We found that while most of our respondents did express a desire for less woody plant cover on their land, woody plant preference did not affect landowner's use of prescribed fire. However, belonging to a prescribed burn association and owning larger properties were correlated with increased use of prescribed fire. Woody plant cover preference was significantly influenced by landownership motivations, with hunters and other recreational motivated landowners preferring more trees and ranchers preferring fewer. This is important because throughout most of our study area, there has been a steady shift from agricultural production to amenity or recreational landownership, a trend that may undermine efforts to restore or maintain open grasslands. Future outreach efforts to promote prescribed fire to maintain grasslands should more actively support prescribed burn associations, which is an effective vehicle for increasing prescribed fire use by private landowners.

Abstract A beta-logistic generalized linear mixed model was used to study the association of national-level forest cover with selected covariates from a sample of 158 nations over the 1992–2013 period. The model avoided the improper assumption of normally distributed forest cover data and used covariates representing land, economic, and social factors. Agricultural land expansion was the most important factor associated with declines in forest cover. Relationships with other covariates are more nuanced. We found no support for an environmental Kuznets curve; however, a Kuznets-like trajectory with population and education variables was discerned. Population density had a negative marginal effect on forest cover up to 220 people/square kilometer (km2) but changed to positive after this threshold. A turning point for proportion of rural population was found at 22% when the association changed from positive to negative. The threshold for education level was 93% when its association switched from negative to positive. Economic variables inclusive of per capita income and 10-year lagged GDP growth rate had a weak but statistically significant association. In the future, high-income nations are expected to continue moderate growth in forest cover; a few fast-urbanizing developing countries are predicted to keep increasing forest area, but most will be likely to see a decline.

Co-firing woody biomass with coal is one approach electricity providers can take to achieve emissions reductions without significantly modifying their existing infrastructure. An important aspect of EPA recommendations for reducing carbon emissions from coal-fired power plants is an allowance for states to enter into multi-state compliance partnerships. This study presents mixed integer linear programming models to identify min-cost approaches for reducing carbon emissions via biomass co-firing subject to spatially-explicit biomass availability constraints, utilising a robust optimisation approach to address uncertainties in costs and emission rates. We apply these models to a set of 18 states in the Northern US, to demonstrate how one state could identify efficient sets of multi-state collaborators.