Forest Biology Commons^™

The Interspecific Growth–Mortality Trade-Off Is Not A General Framework For Tropical Forest Community Structure, Sabrina E. Russo, Sean M. Mcmahon, Matteo Detto, Glenn Ledder, S. Joseph Wright, Richard S. Condit, Stuart J. Davies, Peter S. Ashton, Sarayudh Bunyavejchewin, Chia-Hao Chang-Yang, Sisira Ediriweera, Corneille E.N. Ewango, Christine Fletcher, Robin B. Foster, C.V. Savi Gunatilleke, I.A.U. Nimal Gunatilleke, Terese Hart, Chang-Fu Hseih, Stephen P. Hubbell, Akira Itoh, Abdul Rahman Kassim, Yao Tze Leong, Yi Ching Lin, Jean-Remy Makana, Mohizah Bt. Mohamad, Perry Ong, Anna Sugiyama, I-Fang Sun, Sylvester Tan, Jill Thompson, Takuo Yamakura, Sandra L. Yap, Jess K. Zimmerman

School of Biological Sciences: Faculty Publications

Resource allocation within trees is a zero-sum game. Unavoidable trade-offs dictate that allocation to growth-promoting functions curtails other functions, generating a gradient of investment in growth versus survival along which tree species align, known as the interspecific growth–mortality trade-off. This paradigm is widely accepted but not well established. Using demographic data for 1,111 tree species across ten tropical forests, we tested the generality of the growth–mortality trade-off and evaluated its underlying drivers using two species-specific parameters describing resource allocation strategies: tolerance of resource limitation and responsiveness of allocation to resource access. Globally, a canonical growth–mortality trade-off emerged, but the trade-off …

Timber Talk, Vol. 59, No. 2, June 2021

Timber Talk: Nebraska Forest Industry Newsletter

Timber Talk, Vol. 59, No.2, June 2021

Environmental Data: Geospatial And Elevation Data, Albert J. Burky, Julia I. Chapman, Ryan W. Mcewan

Data Files: Drew Woods Permanent Plots

GPS Coordinates, Elevation, and Distance to Edge data for 32 sample plots in Drew Woods State Nature Preserve in Darke County, OH. Data key is provided in a supplemental file.

Seedling Growth And Soil Chemistry In A Chronosequence Of Forest Restoration From Agriculture, Michaela J. Woods, Sarah J. Frankenberg, Joseph R. Juodvalkis, Mary C. Lloyd, Meredith Cobb, Ryan Mcewan

Five Rivers MetroParks Collaboration Data Archive

Soils were collected from forest restorations that were 0, 7, 10, 50 and 100 years old and assessed for soil nutrients, chemistry, and enzymatic activity. Quercus macrocarpa seedlings were planted in each soil type, after 5 months of growth seedlings were destructively harvested. Seedling mass and the colonization rate of their roots by ectomycorrhizal fungi are reported.

The photo accompanying this data collection is of the researchers' germinating Quercus macrocarpa seeds.

Conifer Encroachment And Removal In A Northern California Oak Woodland: Influences On Ecosystem Physiology And Biodiversity, Gabriel S. Goff

Cal Poly Humboldt theses and projects

Oregon white oak (Quercus garryana) woodlands across their range are becoming increasingly threatened by encroaching Douglas-fir encroachment (Pseudotsuga menziesii) as a result of fire exclusion. Using water potential (Ψ), stomatal conductance (g_s), xylem water stable isotopes (dD), and three metrics of biodiversity, this study investigates the effects of conifer encroachment and removal at the ecosystem-scale. The study was set in an Oregon white oak woodland in northern California and compared three levels of encroachment before and after conifer removal. Findings indicate that heavily encroached stands have the least amount of water stress and gas …

Wildlife Forage Recovery Following Boreal Wildfire, Alexis Jorgensen, Jennifer Baltzer

Theses and Dissertations (Comprehensive)

Climate change is altering the boreal wildfire regime through increases in the extent and severity of burning and reductions in fire return intervals. These changes can alter the regeneration trajectory of canopy species and ground vegetation, with implications for wildlife habitat. There is some uncertainty about the timelines of when different animal species will use burned areas as their preferred forage taxa recover following fire, and how such recovery is mediated by environmental factors. Here, we aim to address these knowledge gaps through the following questions: 1) What are the main forage types consumed by boreal wildlife and how much …

Focus Stacking Images Of Morphological Character States For Differentiating The Adults Of Ixodes Affinis And Ixodes Scapularis (Acari: Ixodidae) In Areas Of Sympatry, Robyn M. Nadolny, Marcée Toliver, Holly D. Gaff, John G. Snodgrass, Richard G. Robbins

Biological Sciences Faculty Publications

Adult females and males of Ixodes affinis and Ixodes scapularis are illustrated by focus stacking image photography, and morphological character states are described that reliably differentiate the two species. In conjunction with other environmental cues, such as the questing phenology of adults, these characteristics will enable the rapid identification of adults of either sex along the southern Coastal Plain of the United States, where these species are sympatric.

Influences On Conifer Drought Responses In Northern California, Wallis L. Robinson

Cal Poly Humboldt theses and projects

California is experiencing increasingly severe and prolonged droughts, which are contributing to changes in tree stress and forest mortality. Many factors affect a tree’s drought response, including competition, climate, and site and tree characteristics. Northern California provides a suitable venue to explore the effects of these factors, as it spans a variety of site conditions and includes habitat for conifers with different adaptations and requirements. This study used annual ¹³C discrimination and growth metrics to assess differences in drought resistance and resilience in conifers adapted to coastal and montane ranges at both wet and dry sites, as well as …

Evaluating Immaturity Risk In Young Stands Of The Serotinous Knobcone Pine (Pinus Attenuata), Katherine Marlin

Cal Poly Humboldt theses and projects

As wildfire becomes increasingly frequent, many plant populations risk local extirpation if fire recurs too soon, a problem dubbed “immaturity risk”. We studied the regeneration of a serotinous conifer species, knobcone pine (Pinus attenuata), as a function of the time between high-severity fires (6-79 years). We evaluated age, cone production, and regeneration at two burned sites in northern California, the Ranch Fire (2018) in Mendocino National Forest, and the Carr Fire (2018) in Whiskeytown National Recreation Area. We found an average of 30.5 filled seeds in closed, brown cones (42% viability of filled seeds). The bulk of the …

Beaver Moderated Fire Resistance In The North Cascades And Potential For Climate Change Adaptation, Joseph John Weirich Iii

EWU Masters Thesis Collection

Climate change and fire suppression have altered historic fire regimes, creating conditions for larger, more intense fires. Intense burns can alter watershed hydrology, increasing the potential for harmful channel incision, which impairs riparian ecosystem function by lowering the water table, disconnecting floodplains from aquatic environments. However, wetlands and functioning riparian zones can reduce burn intensity. Beaver, with their unique ability to build dams, can restore incised and degraded streams, store water, and expand wetland environments, potentially decreasing wildfire intensity, fire spread and create fire breaks across the landscape. My objective was to test the hypothesis that beaver impoundments increase landscape …

Soil Microbial Nitrogen-Transforming Genes Influenced By Tree Species And Fertilization In An Appalachian Hardwood Forest, Emma G. Fox-Fogle

Graduate Theses, Dissertations, and Problem Reports (ETD)

Many forest ecosystems have been receiving elevated nitrogen (N) deposition due to human activity. Increased ecosystem N threatens soil fertility, water and air quality, and modifies the soil microbially-mediated N cycle in complex ways. The current study investigates how the abundance of key functional N cycling genes within soil bacteria is altered by N deposition and further mediated by different dominant tree species at the Fernow Experimental Forest, WV. Soils were analyzed from two watersheds, where watershed 3 (WS 3) has been receiving experimental applications of N fertilizer that are 2x historic ambient N deposition and 5x the current ambient …

Climatic Drivers Of Growth In Mixed Conifer Forests Of The Sierra Nevada For Different Tree Sizes And Thinning Treatments, Andrew M. Hirsch

Graduate Theses, Dissertations, and Problem Reports (ETD)

The Mediterranean region of northern California is projected to get increasingly warmer under all Intergovernmental Panel on Climate Change (IPCC) emission scenarios, with future precipitation projections not showing much of a trend. This poses a problem to the already dry summers that are experienced in the Mediterranean region of California. If precipitation does not increase alongside temperatures, the dry seasons will likely only get drier. The use of dendroclimatology to assess how mixed conifer species in the Sierra Nevada responded to past climate is a key resource that can be used to infer how trees may respond to a future …

A Spatiotemporal Assessment Of Fish Assemblage Response To Land-Use Change And The Evaluation Of Edna Metabarcoding For Describing Diverse Fish Communities, Timothy M. Owen

Theses and Dissertations

Fish assemblages are often assessed as a biological proxy for environmental health. While humans value healthy environments for the ecosystem services and recreational opportunities they provide, it is increasingly evident that such resources can be paradoxically degraded by anthropogenic activities. In this investigation, we studied the relationship between different intensities of anthropogenic land-use change and habitat-driven fish assemblage response across multiple spatiotemporal scales. Secondarily, we explored the efficacy of eDNA metabarcoding against conventional electrofishing techniques for the purpose of describing complete fish communities. This study was conducted in the Tuckahoe Creek basin near Richmond, Virginia. This James River tributary serves …