Scholarly Works, Forest Resources and Environmental Conservation

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Research articles, presentations, and other scholarship


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  • Local knowledge reconstructs historical resource use
    Castello, Leandro; Martins, Eduardo G.; Sorice, Michael G.; Smith, Eric P.; Almedia, Morgana; Bastos, Gastao C.C.; Gardoso, Luis G.; Clauzet, Mariana; Dopona, Alisson P.; Ferreira, Beatrice; Haimovic, Manuel; Jorge, Marcelo; Mendonça, Jocemar; Ávila-da- Silva, Antonio O.; Roman, Ana P.O.; Ramires, Milena; de Miranda, Laura V.; Lopes, Priscila F.M. (Wiley, 2024-03-07)
    Information on natural resource exploitation is vital for conservation but scarce in developing nations, which encompass most of the world and often lack the capacity to produce it. A growing approach to generate information about resource use in the context of developing nations relies on surveys of resource users about their recollections (recall) of past harvests. However, the reliability of harvest recalls remains unclear. Here, we show that harvest recalls can be as accurate to data collected by standardized protocols, despite that recalls are variable and affected by the age of the recollecting person and the length of time elapsed since the event. Samples of harvest recalls permit relatively reliable reconstruction of harvests for up to 39 years in the past. Harvest recalls therefore have strong potential to inform data-poor resource systems and curb shifting baselines around the world at a fraction of the cost of conventional approaches.
  • Forecasting the flooding dynamics of flatwoods salamander breeding wetlands under future climate change scenarios
    Chandler, Houston C.; Caruso, Nicholas M.; McLaughlin, Daniel L.; Jiao, Yan; Brooks, George C.; Haas, Carola A. (PeerJ, 2023-09-19)
    Ephemeral wetlands are globally important systems that are regulated by regular cycles of wetting and drying, which are primarily controlled by responses to relatively short-term weather events (e.g., precipitation and evapotranspiration). Climate change is predicted to have significant effects on many ephemeral wetland systems and the organisms that depend on them through altered filling or drying dates that impact hydroperiod. To examine the potential effects of climate change on pine flatwoods wetlands in the southeastern United States, we created statistical models describing wetland hydrologic regime using an approximately 8-year history of water level monitoring and a variety of climate data inputs. We then assessed how hydrology may change in the future by projecting models forward (2025–2100) under six future climate scenarios (three climate models each with two emission scenarios). We used the model results to assess future breeding conditions for the imperiled Reticulated Flatwoods Salamander (Ambystoma bishopi), which breeds in many of the study wetlands. We found that models generally fit the data well and had good predictability across both training and testing data. Across all models and climate scenarios, there was substantial variation in the predicted suitability for flatwoods salamander reproduction. However, wetlands with longer hydroperiods tended to have fewer model iterations that predicted at least five consecutive years of reproductive failure (an important metric for population persistence). Understanding potential future risk to flatwoods salamander populations can be used to guide conservation and management actions for this imperiled species.
  • A Comparison of Probability Density Functions Fitted by Moments and Maximum Likelihood Estimation Methods Used for Diameter Distribution Estimation
    Gorgoso-Varela, Jose Javier; Adedapo, Segun M.; Ogana, Friday N. (MDPI, 2024-02-22)
    Modeling diameter distribution is a crucial aspect of forest management, requiring the selection of an appropriate probability density function or cumulative distribution function along with a fitting method. This study compared the suitability of eight probability density functions—A Charlier, beta, generalized beta, gamma, Gumbel, Johnson’s SB, and Weibull (two- and three-parameter)—fitted using both derivative methods (Moments) fitted in SAS/STATTM and optimization methods (MLE) fitted with the ‘optim’ function in R for diameter distribution estimation in forest stands. The A Charlier and Gumbel functions were used for the first time in this type of comparison. The data were derived from 167 permanent sample plots in an Atlantic forest (Quercus robur) and 59 temporary sample plots in tropical forests (Tectona grandis). Fit quality was assessed using various indices, including Kolmogorov–Smirnov, Cramér–von Mises, mean absolute error, bias, and mean squared error. The results indicated that Johnson’s SB function was more suitable for describing the diameter distribution of the stands. Johnson’s SB, three-parameter Weibull, and generalized beta consistently performed well across different fitting methods, while the fits produced by gamma, Gumbel, and two-parameter Weibull were of poor quality.
  • Effects of establishment fertilization on Landsat-assessed leaf area development of loblolly pine stands
    House, Matthew N.; Wynne, Randolph H.; Thomas, Valerie A.; Cook, Rachel L.; Carter, David R.; Van Mullekom, Jennifer H.; Rakestraw, Jim; Schroeder, Todd A. (Elsevier, 2024-03-15)
    Loblolly pine (Pinus taeda L.) plantations in the southeastern United States are among the world's most intensively managed forest plantations. Under intensive management, a common practice is fertilizing at establishment. The objective of this study was to investigate the effect of establishment fertilization on leaf area development of loblolly pine plantation stands (n = 3997) over 16 years compared to stands that did not receive nutrient additions at planting. Leaf area index (LAI) is a meaningful biophysical indicator of vigor and an important functional and structural element of a planted stand. The study area was stratified by plant hardiness zone to account for climatic differences and soil type (texture and drainage class), using the Cooperative Research in Forest Fertilization (CRIFF) groupings. LAI was estimated from Landsat imagery to create trajectories of mean stand LAI over 16 years. Establishment fertilization, on average, (1) increased stand LAI beginning at year two, with a peak at years six and seven, and (2) decreased the time required for a stand to reach a winter LAI of 1.5 by almost two years. Fertilization responses varied by climate zone and soil drainage class, where the warmest zones benefited the most, particularly in poorly drained soils. Past year 10, the differences in LAI between fertilized and unfertilized stands were not practically important. Using Landsat data in a cloud-computing environment, we demonstrated the benefits of establishment fertilization to stand LAI development using a large sample over the native range of loblolly pine.
  • Tree Performance in a Stormwater Bioretention System
    Apisa, Ethan; Wiseman, P. Eric (2022-01-25)
    Stormwater runoff from impervious surfaces in urban areas causes water pollution and flash flooding. Trees can help solve this problem by capturing and absorbing rain. However, there is often not enough space in cities for both trees and conventional stormwater control systems. Various bioretention systems that incorporate trees are used in cities, but they are expensive and complex, which makes their implementation difficult. We are investigating a system that may prove to be less complex, less costly, and better for growing trees. Our full-scale prototype of this system was constructed in 2020 adjacent to a parking lot on the Virginia Tech campus in Blacksburg, VA. It comprises a belowground gravel bed surrounding a soil bed where trees are planted. The gravel bed stores a large volume of parking lot runoff that is then absorbed by the tree roots and expelled to the air through transpiration. Our long-term study of this prototype aims to understand how well the system captures and stores runoff and how well the trees perform compared to control trees in a standard planting nearby. We are monitoring tree crown and root growth, photosynthesis, and leaf stomatal conductance. Growth and physiology of the trees in the system has been comparable to the control trees since being planted in May 2020.
  • Documentation and Conservation of Champion Big Trees in Urban Forests
    Wiseman, P. Eric (2023-11-14)
    North Carolina Community Tree Webinar
  • Resilient Tree Species for Urban Environments in Virginia
    Wiseman, P. Eric (2023-06-09)
    Virginia Cooperative Extension Master Gardener College
  • Creating Storm-Resilient Urban Forests
    Wiseman, P. Eric (2023-03-15)
    Roanoke Tree Care Workshop
  • Principles and Practices for Pruning Trees Around the Home and Landscape
    Wiseman, P. Eric (2023-02-11)
    Southwest Landowner Woods & Wildlife 2023 Conference
  • A Comparison of Forest Biomass and Conventional Harvesting Effects on Estimated Erosion, Best Management Practice Implementation, Ground Cover, and Residual Woody Debris in Virginia
    Garren, Austin M.; Bolding, Michael Chad; Barrett, Scott M.; Hawks, Eric M.; Aust, Wallace Michael; Coates, Thomas Adam (MDPI, 2023-11-17)
    Expanding markets for renewable energy feedstocks have increased demand for woody biomass. Concerns associated with forest biomass harvesting include increased erosion, the applicability of conventional forestry Best Management Practices (BMPs) for protecting water quality, and reduced woody debris retention for soil nutrients and cover. We regionally compared the data and results from three prior independent studies that estimated erosion, BMP implementation, and residual woody debris following biomass and conventional forest harvests in the Mountains, Piedmont, and Coastal Plain of Virginia. Estimated erosion was higher in the Mountains due to steep slopes and operational challenges. Mountain skid trails were particularly concerning, comprising only 8.47% of the total area but from 37.9 to 81.1% of the total site-wide estimated erosion. BMP implementation varied by region and harvest type, with biomass sites having better implementation than conventional sites, and conventional Mountain sites having lower implementation than other regions. Sufficient woody debris remained for BMPs on both harvest types in all regions, with conventional Mountain sites retaining twice that of Coastal Plain sites. BMPs reduced the estimated erosion on both site types suggesting increased implementation could reduce potential erosion in problematic areas. Therefore, proper BMP implementation should be ensured, particularly in Mountainous terrain, regardless of harvest type.
  • A community convention for ecological forecasting: output files and metadata v1.0
    Dietze, Michael C.; Thomas, R. Quinn; Peters, Jody; Boettiger, Carl; Koren, Gerbrand; Shiklomanov, Alexey N.; Ashander, Jaime (Wiley, 2023-11-23)
    This paper summarizes the open community conventions developed by the Ecological Forecasting Initiative (EFI) for the common formatting and archiving of ecological forecasts and the metadata associated with these forecasts. Such open standards are intended to promote interoperability and facilitate forecast communication, distribution, validation, and synthesis. For output files, we first describe the convention conceptually in terms of global attributes, forecast dimensions, forecasted variables, and ancillary indicator variables. We then illustrate the application of this convention to the two file formats that are currently preferred by the EFI, netCDF (network common data form), and comma-separated values (CSV), but note that the convention is extensible to future formats. For metadata, EFI's convention identifies a subset of conventional metadata variables that are required (e.g., temporal resolution and output variables) but focuses on developing a framework for storing information about forecast uncertainty propagation, data assimilation, and model complexity, which aims to facilitate cross-forecast synthesis. The initial application of this convention expands upon the Ecological Metadata Language (EML), a commonly used metadata standard in ecology. To facilitate community adoption, we also provide a Github repository containing a metadata validator tool and several vignettes in R and Python on how to both write and read in the EFI standard. Lastly, we provide guidance on forecast archiving, making an important distinction between short-term dissemination and long-term forecast archiving, while also touching on the archiving of code and workflows. Overall, the EFI convention is a living document that can continue to evolve over time through an open community process.
  • Hacking Limnology Workshops and DSOS23: Growing a Workforce for the Nexus of Data Science, Open Science, and the Aquatic Sciences
    Meyer, M. F.; Harlan, M. E.; Hensley, R. T.; Zhan, Q.; Börekçi, N. S.; Bucak, T.; Cramer, A. N.; Feldbauer, J.; Ladwig, R.; Mesman, J. P.; Oleksy, I. A.; Pilla, R. M.; Zwart, J. A.; Calamita, E.; Gubbins, N. J.; Lofton, M. E.; Maciel, D. A.; Marzolf, N. S.; Olsson, F.; Thellman, A. N.; Thomas, R. Quinn; Vlah, M. J. (Wiley, 2023-10-20)
  • Does environmental education work differently across sociopolitical contexts in the United States? PART I. Exploration of outcomes for adolescent youth
    Thorpe, Emily G.; Stern, Marc J.; Powell, Robert B.; Hemby, Tyler L. (Routledge, 2023-10-28)
    In the United States, the two main political parties, Democrats and Republicans, have become increasingly polarized, including with regard to environmental issues. As part of a national study of environmentally focused single-day field trips for early adolescent youth in 2018, we conducted exploratory research to examine how outcomes differed for public school students from different sociopolitical contexts (i.e. predominantly Democratic, Republican, or mixed). Students from wealthier Democratic contexts exhibited less positive outcomes, measured as self-reported changes in environmental literacy, compared to others. The findings suggest that single-day EE field trips in the United States, in their current forms, may be particularly valuable in lower income and more politically conservative contexts, possibly due to the degree of novelty they may provide to these audiences. Meanwhile, EE field trips for students from wealthier Democratic contexts may provide reinforcement rather than meaningful shifts in environmental literacy, suggesting a need for more novel approaches for these audiences.
  • Does environmental education work differently across sociopolitical contexts in the United States? Part II. Examining pedagogy in school field trip programs for early adolescent youth across political contexts
    Thorpe, Emily G.; Stern, Marc J.; Powell, Robert B.; Hemby, Tyler L. (Routledge, 2023-12-16)
    Political polarization in the United States has made many environmental issues strongly partisan, with Democrats largely receptive to environmental messaging and Republicans commonly pitted against it. This phenomenon may have meaningful implications for how environmental education is conducted for people from different sociopolitical contexts. We explored whether certain pedagogical approaches to single-day environmental education field trip programs were linked to better or worse outcomes for early adolescent youth (ages 10–14) from different sociopolitical contexts: majority Republican, majority Democrat, or mixed (roughly even). All observed effect sizes were small with one exception. Play-based pedagogies tended to yield less positive outcomes for students from Republican majority contexts than others, with a medium effect size. The findings suggest that some traditional approaches to play, such as role-playing as animals or pretending to be water droplets, may feel incongruent with the social identities of students from largely Republican communities.
  • Near-term investments in forest management support long-term carbon sequestration capacity in forests of the United States
    Coulston, John W.; Domke, Grant M.; Walker, David M.; Brooks, Evan B.; O'Dea, Claire B. (Oxford University Press, 2023-11-21)
    The forest carbon sink of the United States offsets emissions in other sectors. Recently passed US laws include important climate legislation for wildfire reduction, forest restoration, and forest planting. In this study, we examine how wildfire reduction strategies and planting might alter the forest carbon sink. Our results suggest that wildfire reduction strategies reduce carbon sequestration potential in the near term but provide a longer term benefit. Planting initiatives increase carbon sequestration but at levels that do not offset lost sequestration from wildfire reduction strategies. We conclude that recent legislation may increase near-term carbon emissions due to fuel treatments and reduced wildfire frequency and intensity, and expand long-term US carbon sink strength.
  • Uncertainty in projections of future lake thermal dynamics is differentially driven by lake and global climate models
    Wynne, Jacob H.; Woelmer, Whitney; Moore, Tadhg N.; Thomas, R. Quinn; Weathers, Kathleen C.; Carey, Cayelan C. (PeerJ, 2023-06-02)
    Freshwater ecosystems provide vital services, yet are facing increasing risks from global change. In particular, lake thermal dynamics have been altered around the world as a result of climate change, necessitating a predictive understanding of how climate will continue to alter lakes in the future as well as the associated uncertainty in these predictions. Numerous sources of uncertainty affect projections of future lake conditions but few are quantified, limiting the use of lake modeling projections as management tools. To quantify and evaluate the effects of two potentially important sources of uncertainty, lake model selection uncertainty and climate model selection uncertainty, we developed ensemble projections of lake thermal dynamics for a dimictic lake in New Hampshire, USA (Lake Sunapee). Our ensemble projections used four different climate models as inputs to five vertical one-dimensional (1-D) hydrodynamic lake models under three different climate change scenarios to simulate thermal metrics from 2006 to 2099. We found that almost all the lake thermal metrics modeled (surface water temperature, bottom water temperature, Schmidt stability, stratification duration, and ice cover, but not thermocline depth) are projected to change over the next century. Importantly, we found that the dominant source of uncertainty varied among the thermal metrics, as thermal metrics associated with the surface waters (surface water temperature, total ice duration) were driven primarily by climate model selection uncertainty, while metrics associated with deeper depths (bottom water temperature, stratification duration) were dominated by lake model selection uncertainty. Consequently, our results indicate that researchers generating projections of lake bottom water metrics should prioritize including multiple lake models for best capturing projection uncertainty, while those focusing on lake surface metrics should prioritize including multiple climate models. Overall, our ensemble modeling study reveals important information on how climate change will affect lake thermal properties, and also provides some of the first analyses on how climate model selection uncertainty and lake model selection uncertainty interact to affect projections of future lake dynamics.
  • The NEON Ecological Forecasting Challenge
    Thomas, R. Quinn; Boettiger, Carl; Carey, Cayelan C.; Dietze, Michael C.; Johnson, Leah R.; Kenney, Melissa A.; McLachlan, Jason S.; Peters, Jody A.; Sokol, Eric R.; Weltzin, Jake F.; Willson, Alyssa; Woelmer, Whitney M. (Wiley, 2023-04)
  • Progress and opportunities in advancing near-term forecasting of freshwater quality
    Lofton, Mary E.; Howard, Dexter W.; Thomas, R. Quinn; Carey, Cayelan C. (Wiley, 2023-04)
    Near-term freshwater forecasts, defined as sub-daily to decadal future predictions of a freshwater variable with quantified uncertainty, are urgently needed to improve water quality management as freshwater ecosystems exhibit greater variability due to global change. Shifting baselines in freshwater ecosystems due to land use and climate change prevent managers from relying on historical averages for predicting future conditions, necessitating near-term forecasts to mitigate freshwater risks to human health and safety (e.g., flash floods, harmful algal blooms) and ecosystem services (e.g., water-related recreation and tourism). To assess the current state of freshwater forecasting and identify opportunities for future progress, we synthesized freshwater forecasting papers published in the past 5 years. We found that freshwater forecasting is currently dominated by near-term forecasts of water quantity and that near-term water quality forecasts are fewer in number and in the early stages of development (i.e., non-operational) despite their potential as important preemptive decision support tools. We contend that more freshwater quality forecasts are critically needed and that near-term water quality forecasting is poised to make substantial advances based on examples of recent progress in forecasting methodology, workflows, and end-user engagement. For example, current water quality forecasting systems can predict water temperature, dissolved oxygen, and algal bloom/toxin events 5 days ahead with reasonable accuracy. Continued progress in freshwater quality forecasting will be greatly accelerated by adapting tools and approaches from freshwater quantity forecasting (e.g., machine learning modeling methods). In addition, future development of effective operational freshwater quality forecasts will require substantive engagement of end users throughout the forecast process, funding, and training opportunities. Looking ahead, near-term forecasting provides a hopeful future for freshwater management in the face of increased variability and risk due to global change, and we encourage the freshwater scientific community to incorporate forecasting approaches in water quality research and management.