Life Sciences Commons^™

Hydrochorous Seed Dispersal In Riparian Forests Altered By Urbanization, Christa Von Behren, J. Alan Yeakley

Environmental Science and Management Faculty Publications and Presentations

While riparian habitat alterations from urban stream syndrome are known to affect vegetation establishment and survival, the degree to which riparian seed delivery by hydrochory is affected by urbanization is unclear. We hypothesized that (1) there would be a reduction in the overall number of seeds deposited by streams as watershed urbanization increased; and (2) in the most urbanized watersheds, seeds deposited by water would be predominantly from species with traits favoring dispersal in general, including tall stature and high seed production, and favoring deposition by water in particular, including large seed size and the presence of a dispersal appendage. …

Bioenergy Harvest, Climate Change, And Forest Carbon In The Oregon Coast Range, Megan K. Creutzburg, Robert M. Scheller, Melissa S. Lucash, Louisa B. Evers, Stephen D. Leduc, Mark G. Johnson

Environmental Science and Management Faculty Publications and Presentations

Forests provide important ecological, economic and social services, and recent interest has emerged in the potential for using residue from timber harvest as a source of renewable woody bioenergy. The long-term consequences of such intensive harvest are unclear, particularly as forests face novel climatic conditions over the next century. We used a simulation model to project the long-term effects of management and climate change on above- and below ground carbon storage in a watershed in northwestern Oregon. The multi-ownership watershed has a diverse range of current management practices, including little-to-no harvesting on federal lands, short-rotation clear-cutting on industrial land, and …

Climate-Suitable Planting As A Strategy For Maintaining Forest Productivity And Functional Diversity, Matthew Joshua Duveneck, Robert M. Scheller

Environmental Science and Management Faculty Publications and Presentations

Within the time frame of the longevity of tree species, climate change will change faster than the ability of natural tree migration. Migration lags may result in reduced productivity and reduced diversity in forests under current management and climate change. We evaluated the efficacy of planting climate-suitable tree species (CSP), those tree species with current or historic distributions immediately south of a focal landscape, to maintain or increase aboveground biomass, productivity, and species and functional diversity. We modeled forest change with the LANDIS-II forest simulation model for 100 years (2000–2100) at a 2-ha cell resolution and five-year time steps within …

Re-Envisioning Community-Wildfire Relations In The U.S. West As Adaptive Governance, Jesse B. Abrams, Melanie Knapp, Travis B. Paveglio, Autumn Ellison, Cassandra Moseley, Max Nielsen-Pincus, Matthew S. Carroll

Environmental Science and Management Faculty Publications and Presentations

Prompted by a series of increasingly destructive, expensive, and highly visible wildfire crises in human communities across the globe, a robust body of scholarship has emerged to theorize, conceptualize, and measure community-level resilience to wildfires. To date, however, insufficient consideration has been given to wildfire resilience as a process of adaptive governance mediated by institutions at multiple scales. Here we explore the possibilities for addressing this gap through an analysis of wildfire resilience among wildland-urban interface communities in the western region of the United States. We re-engage important but overlooked components of social-ecological system resilience by situating rural communities within …

Carbon Dynamics In The Future Forest: The Importance Of Long-Term Successional Legacy And Climate–Fire Interactions, E. Louise Loudermilk, Robert M. Scheller, Peter J. Weisberg, Jian Yang, Thomas E. Dilts, Sarah L. Karam, Carl Skinner

Environmental Science and Management Faculty Publications and Presentations

Understanding how climate change may influence forest carbon (C) budgets requires knowledge of forest growth relationships with regional climate, long-term forest succession, and past and future disturbances, such as wildfires and timber harvesting events. We used a landscape-scale model of forest succession, wildfire, and C dynamics (LANDIS-II) to evaluate the effects of a changing climate (A2 and B1 IPCC emissions; Geophysical Fluid Dynamics Laboratory General Circulation Models) on total forest C, tree species composition, and wildfire dynamics in the Lake Tahoe Basin, California, and Nevada. The independent effects of temperature and precipitation were assessed within and among climate models. Results …

Divergent Carbon Dynamics Under Climate Change In Forests With Diverse Soils, Tree Species, And Land Use Histories, Robert M. Scheller, Alec M. Kretchun, Steve Van Tuyl, Kenneth L. Clark, Melissa S. Lucash, John Hom

Environmental Science and Management Faculty Publications and Presentations

Accounting for both climate change and natural disturbances—which typically result in greenhouse gas emissions—is necessary to begin managing forest carbon sequestration. Gaining a complete understanding of forest carbon dynamics is, however, challenging in systems characterized by historic over-utilization, diverse soils and tree species, and frequent disturbance. In order to elucidate the cascading effects of potential climate change on such systems, we projected forest carbon dynamics, including soil carbon changes, and shifts in tree species composition as a consequence of wildfires and climate change in the New Jersey pine barrens (NJPB) over the next 100 years. To do so, we used …

The Influence Of Land Use And Climate Change On Forest Biomass And Composition In Massachusetts, Usa, Jonathan R. Thompson, David R. Foster, Robert M. Scheller, David Kittridge

Environmental Science and Management Faculty Publications and Presentations

Land use and climate change have complex and interacting effects on naturally dynamic forest landscapes. To anticipate and adapt to these changes, it is necessary to understand their individual and aggregate impacts on forest growth and composition. We conducted a simulation experiment to evaluate regional forest change in Massachusetts, USA over the next 50 years (2010–2060). Our objective was to estimate, assuming a linear continuation of recent trends, the relative and interactive influence of continued growth and succession, climate change, forest conversion to developed uses, and timber harvest on live aboveground biomass (AGB) and tree species composition. We examined 20 …

Predicting Global Change Effects On Forest Biomass And Composition In South-Central Siberia, Eric J. Gustafson, Anatoly Z. Shvidenko, Brian R. Sturtevant, Robert M. Scheller

Environmental Science and Management Faculty Publications and Presentations

Multiple global changes such as timber harvesting in areas not previously disturbed by cutting and climate change will undoubtedly affect the composition and spatial distribution of boreal forests, which will, in turn, affect the ability of these forests to retain carbon and maintain biodiversity. To predict future states of the boreal forest reliably, it is necessary to understand the complex interactions among forest regenerative processes (succession), natural disturbances (e.g., fire, wind, and insects), and anthropogenic disturbances (e.g., timber harvest). We used a landscape succession and disturbance model (LANDIS-II) to study the relative effects of climate change, timber harvesting, and insect …

Increasing The Reliability Of Ecological Models Using Modern Software Engineering Techniques, Robert M. Scheller, Brian R. Sturtevant, Eric J. Gustafson, Brendan C. Ward, David J. Mladenoff

Environmental Science and Management Faculty Publications and Presentations

Modern software development techniques are largely unknown to ecologists. Typically, ecological models and other software tools are developed for limited research purposes, and additional capabilities are added later, usually in an ad hoc manner. Modern software engineering techniques can substantially increase scientific rigor and confidence in ecological models and tools. These techniques have the potential to transform how ecological software is conceived and developed, improve precision, reduce errors, and increase scientific credibility. We describe our re-engineering of the forest landscape model LANDIS (LANdscape DIsturbance and Succession) to illustrate the advantages of using common software engineering practices.

Manejo De Cipós Na Amazônia, Jeffrey J. Gerwing, Edson Vidal

Environmental Science and Management Faculty Publications and Presentations

Levantamentos florestais revelam que os cipós vêm se tornando cada vez mais abundantes em toda a Amazônia, tanto em florestas intactas quanto nas afetadas por atividades humanas, como a exploração de madeira. Nessa atividade, é recomendado o corte dos cipós ligados à árvore escolhida, para reduzir os danos às demais durante a queda. Conhecer a ecologia desse grupo de plantas e seu adequado manejo é essencial para entender as conseqüências do seu corte e para cumprir as metas de conservação da biodiversidade incluídas nos projetos de manejo de florestas tropicais.

Pre-Logging Liana Cutting Reduces Liana Regeneration In Logging Gaps In The Eastern Brazilian Amazon, Jeffrey J. Gerwing, Christopher Uhl

Environmental Science and Management Faculty Publications and Presentations

The cutting of all lianas prior to logging is a reduced-impact logging technique that is predicted to reduce liana proliferation in logging gaps. This study compares liana abundance and species composition in gaps created during conventional and reduced-impact logging in a forest of the eastern Brazilian Amazon. Logging treatments were conducted in side-by-side plots. Shortly following logging, 50-m² plots were located in the approximate centers of four single treefall and four multiple treefall gaps in each logging area. Six years following logging, there were ∼40% fewer climbing lianas in reduced-impact gaps than in conventional logging gaps. In both logging …

Integrating Liana Abundance And Forest Stature Into An Estimate Of Total Aboveground Biomass For An Eastern Amazonian Forest, Jeffrey J. Gerwing, Damiao Lopes Farias

Environmental Science and Management Faculty Publications and Presentations

This study provides an estimate of aboveground live biomass for an intact eastern Amazonian forest. An allometric regression biomass equation was developed to estimate the aboveground biomass of live lianas. This equation, together with a previously published equation for trees, was then used to estimate the contributions of lianas and trees to the total biomass of forest patches in four stature classes: gap (openings in the canopy of at least 25 m2 with the dominant vegetation < 3 m high), low (3±15 m canopy height), medium (15±25 m canopy height), and high (> 25 m canopy height). Total stand-level biomass was estimated as the weighted average of the stature classes. In 130 ha of surveyed forest, forest …

Acorn Foraging As A Means To Explore Human Energetics And Forge Connections To Local Forests, Jeffrey J. Gerwing, Pamela Lockwood, Christopher Uhl

Environmental Science and Management Faculty Publications and Presentations

Jeffrey Gerwing, Pamela Lockwood, and Christopher Uhl describe a rather unusual ecology laboratory/field exercise that utilizes abundant oak habitats of central Pennsylvania. For those readers not blessed with an abundant supply of oaks nearby, perhaps other species could be substituted. The exercise is unusual in two ways. It offers a new undergraduate ecology activity, and it offers opportunities for students to relate other disciplines to their science course.

In "the good old days" of higher education each discipline offered its menu of courses and expected students to make appropriate connections among the courses of their major, minor, and general education. …