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Full-Text Articles in Life Sciences

Fresh Air For The Mire-Breathing Hypothesis: Sphagnum Moss And Peat Structure Regulate The Response Of Co2 Exchange To Altered Hydrology In A Northern Peatland Ecosystem, Ally O’Neill, Colin Tucker, Evan S. Kane Oct 2022

Fresh Air For The Mire-Breathing Hypothesis: Sphagnum Moss And Peat Structure Regulate The Response Of Co2 Exchange To Altered Hydrology In A Northern Peatland Ecosystem, Ally O’Neill, Colin Tucker, Evan S. Kane

Michigan Tech Publications

Sphagnum-dominated peatlands store more carbon than all of Earth’s forests, playing a large role in the balance of carbon dioxide. However, these carbon sinks face an uncertain future as the changing climate is likely to cause water stress, potentially reducing Sphagnum productivity and transitioning peatlands to carbon sources. A mesocosm experiment was performed on thirty-two peat cores collected from two peatland landforms: elevated mounds (hummocks) and lower, flat areas of the peatland (hollows). Both rainfall treatments and water tables were manipulated, and CO2 fluxes were measured. Other studies have observed peat subsiding and tracking the water table downward when experiencing …


European Mushroom Assemblages Are Phylogenetically Structured By Temperature, Claus Bässler, Jacob Heilmann-Clausen, Carrie Andrew, Lynne Boddy, Ulf Büntgen, Jeffrey Diez, Et. Al. Sep 2022

European Mushroom Assemblages Are Phylogenetically Structured By Temperature, Claus Bässler, Jacob Heilmann-Clausen, Carrie Andrew, Lynne Boddy, Ulf Büntgen, Jeffrey Diez, Et. Al.

Michigan Tech Publications

Recent global warming affects species compositions at an unprecedented rate. To predict climate-induced changes in species assemblages, a better understanding of the link between species occurrence and climate is needed. Macrofungal fruit body assemblages are correlated with the thermal environment at the European scale. However, it is still unknown whether macrofungal communities are also phylogenetically structured by thermal environments. Thermal environments are characterized by annual temperature means but also by intra-annual temperature variability (hereafter termed temperature seasonality), which are both considered in this study. Here, we used distribution data of 2882 species based on fruit body records across Europe to …


Joint Impacts Of Future Climate Conditions And Invasive Species On Black Ash Forested Wetlands, Joseph Shannon, Randall Kolka, Matthew Van Grinsven, Fengjing Liu Aug 2022

Joint Impacts Of Future Climate Conditions And Invasive Species On Black Ash Forested Wetlands, Joseph Shannon, Randall Kolka, Matthew Van Grinsven, Fengjing Liu

Michigan Tech Publications

Wetlands around the globe are being impacted by changing temperature and precipitation patterns. Simultaneously black ash forested wetlands are expected to lose much of their overstory canopy due to the invasive Emerald Ash Borer (EAB). Field experiments and modeling efforts have provided information on species tolerance of post-EAB conditions and future climate adapted species. No studies have yet examined the interaction of the loss of ash and future climate scenarios on wetland hydrologic conditions. We developed daily wetland hydrology models for three vegetation conditions: black ash forest, alternate non-ash forest, and non-forested. Model simulations were evaluated under current climate conditions …


Evaluating Current And Future Potential Distribution Of Epiphytic Orchids In The Congo Basin With Ecological Niche Models, Michael L. Ngoh Aug 2022

Evaluating Current And Future Potential Distribution Of Epiphytic Orchids In The Congo Basin With Ecological Niche Models, Michael L. Ngoh

Masters Theses

The Congo Basin Forest harbors a rich diversity of epiphytic communities, with the Orchidaceae alone making up more than 50% of all epiphytes in the region. Despite the huge diversity of epiphytes, many species, including epiphytic orchids, are at risk to a diverse array of threats. Climate change for instance poses severe threats to epiphytic orchids due to elevated temperatures, prolonged periods of droughts, as well as reduced rainfall across the Congo Basin Forest. In this study, we used ecological niche modeling and GIS techniques to identify spatial patterns of species richness, potential future climate refugia, and novel climatic suitability …


Understory Plant Communities Show Resistance To Drought, Hurricanes, And Experimental Warming In A Wet Tropical Forest, Aura M. Alonso-Rodríguez, Tana E. Wood, Jamarys Torres-Díaz, Molly A. Cavaleri, Sasha C. Reed, Benedicte Bachelot Jul 2022

Understory Plant Communities Show Resistance To Drought, Hurricanes, And Experimental Warming In A Wet Tropical Forest, Aura M. Alonso-Rodríguez, Tana E. Wood, Jamarys Torres-Díaz, Molly A. Cavaleri, Sasha C. Reed, Benedicte Bachelot

Michigan Tech Publications

Global climate change has led to rising temperatures and to more frequent and intense climatic events, such as storms and droughts. Changes in climate and disturbance regimes can have non-additive effects on plant communities and result in complicated legacies we have yet to understand. This is especially true for tropical forests, which play a significant role in regulating global climate. We used understory vegetation data from the Tropical Responses to Altered Climate Experiment (TRACE) in Puerto Rico to evaluate how plant communities responded to climate warming and disturbance. The TRACE understory vegetation was exposed to a severe drought (2015), 2 …


Climate Sensitive Diameter Growth Models For Major Tree Species In Mississippi, Sujan Subedi May 2022

Climate Sensitive Diameter Growth Models For Major Tree Species In Mississippi, Sujan Subedi

Theses and Dissertations

Anticipated climate change and increasing wood demand require dependable diameter growth models for adaptive forest management. We used a mixed-effects modeling approach with Forest Inventory and Analysis (FIA) data to fit diameter growth models for loblolly pine, other softwood species (slash pine, shortleaf pine, and longleaf pine), sweetgum, and other hardwood (southern red oak, red maple, and water oak) species. Climatic variables coupled with individual tree attributes and competition factors improved climate insensitive models. Growth of loblolly pine and sweetgum was positively correlated with mean temperature of the coldest month. Mean temperature of the warmest month negatively influenced diameter growth …


Climate Effects On Black Spruce And Trembling Aspen Productivity In Natural Origin Mixed Stands, Mahadev Sharma Mar 2022

Climate Effects On Black Spruce And Trembling Aspen Productivity In Natural Origin Mixed Stands, Mahadev Sharma

Aspen Bibliography

Forest managers need site productivity estimates for tree species growing in mixed stands. Models developed in the past are generally for pure stands and don’t factor in the effects of climate change on site productivity. Therefore, site index (SI) models were developed for black spruce (Picea mariana Mill. B.S.P.) and trembling aspen (Populus tremuloides Michx.) trees grown in natural origin mixed stands. For this, 186 trees (93 black spruce and trembling aspen each) were sampled from 31 even-aged natural mixed stands (sites) (3 trees/species/site) across Ontario, Canada. Stand height growth models were developed by incorporating climate variables during …


Wind And Fire: Rapid Shifts In Tree Community Composition Following Multiple Disturbances In The Southern Boreal Forest, Elias Anoszko, Lee E. Frelich, Roy L. Rich, Peter B. Reich Mar 2022

Wind And Fire: Rapid Shifts In Tree Community Composition Following Multiple Disturbances In The Southern Boreal Forest, Elias Anoszko, Lee E. Frelich, Roy L. Rich, Peter B. Reich

Aspen Bibliography

Under a warming climate, the southern boreal forest of North America is expected to see a doubling in fire frequency and potential for increased wind disturbance over the next century. Although boreal forests are often considered fire-adapted, projected increases in disturbance frequency will likely result in novel combinations of disturbances with severities and impacts on community composition outside historic norms. Using a network of repeatedly measured vegetation monitoring plots, we followed changes in tree community composition in areas of the Boundary Waters Canoe Area Wilderness (BWCAW), in Minnesota, USA, experiencing disturbances ranging from severe windstorms or wildfires to areas affected …


Bottom-Up Drivers Of Future Fire Regimes In Western Boreal North America, Adrianna C. Foster, Jacquelyn K. Shuman, Brendan M. Rogers, Xanthe J. Walker, Michelle C. Mack, Laura L. Bourgeau-Chavez, Sander Veraverbeke, Scott J. Goetz Jan 2022

Bottom-Up Drivers Of Future Fire Regimes In Western Boreal North America, Adrianna C. Foster, Jacquelyn K. Shuman, Brendan M. Rogers, Xanthe J. Walker, Michelle C. Mack, Laura L. Bourgeau-Chavez, Sander Veraverbeke, Scott J. Goetz

Aspen Bibliography

Forest characteristics, structure, and dynamics within the North American boreal region are heavily influenced by wildfire intensity, severity, and frequency. Increasing temperatures are likely to result in drier conditions and longer fire seasons, potentially leading to more intense and frequent fires. However, an increase in deciduous forest cover is also predicted across the region, potentially decreasing flammability. In this study, we use an individual tree-based forest model to test bottom-up (i.e. fuels) vs top-down (i.e. climate) controls on fire activity and project future forest and wildfire dynamics. The University of Virginia Forest Model Enhanced is an individual tree-based forest model …


Montane Temperate-Boreal Forests Retain The Leaf Economic Spectrum Despite Intraspecific Variability, Matthew J. Hecking, Jenna M. Zukswert, John E. Drake, Martin Dovciak, Julia I. Burton Jan 2022

Montane Temperate-Boreal Forests Retain The Leaf Economic Spectrum Despite Intraspecific Variability, Matthew J. Hecking, Jenna M. Zukswert, John E. Drake, Martin Dovciak, Julia I. Burton

Michigan Tech Publications

Trait-based analyses provide powerful tools for developing a generalizable, physiologically grounded understanding of how forest communities are responding to ongoing environmental changes. Key challenges lie in (1) selecting traits that best characterize the ecological performance of species in the community and (2) determining the degree and importance of intraspecific variability in those traits. Recent studies suggest that globally evident trait correlations (trait dimensions), such as the leaf economic spectrum, may be weak or absent at local scales. Moreover, trait-based analyses that utilize a mean value to represent a species may be misleading. Mean trait values are particularly problematic if species …


Identifying Conifer Tree Vs. Deciduous Shrub And Tree Regeneration Trajectories In A Space-For-Time Boreal Peatland Fire Chronosequence Using Multispectral Lidar, Humaira Enayetullah, Laura Chasmer, Christopher Hopkinson, Dan Thompson, Danielle Cobbaert Jan 2022

Identifying Conifer Tree Vs. Deciduous Shrub And Tree Regeneration Trajectories In A Space-For-Time Boreal Peatland Fire Chronosequence Using Multispectral Lidar, Humaira Enayetullah, Laura Chasmer, Christopher Hopkinson, Dan Thompson, Danielle Cobbaert

Aspen Bibliography

Wildland fires and anthropogenic disturbances can cause changes in vegetation species composition and structure in boreal peatlands. These could potentially alter regeneration trajectories following severe fire or through cumulative impacts of climate-mediated drying, fire, and/or anthropogenic disturbance. We used lidar-derived point cloud metrics, and site-specific locational attributes to assess trajectories of post-disturbance vegetation regeneration in boreal peatlands south of Fort McMurray, Alberta, Canada using a space-for-time-chronosequence. The objectives were to (a) develop methods to identify conifer trees vs. deciduous shrubs and trees using multi-spectral lidar data, (b) quantify the proportional coverage of shrubs and trees to determine environmental conditions driving …


Differential Water-Use And Growth Responses Of Pinus Densiflora And Larix Kaempferi Seedlings To Microclimate Manipulation, Jiae An, Hanna Chang, Seung Hyun Han, Asia Khamzina, Yowhan Son Jan 2022

Differential Water-Use And Growth Responses Of Pinus Densiflora And Larix Kaempferi Seedlings To Microclimate Manipulation, Jiae An, Hanna Chang, Seung Hyun Han, Asia Khamzina, Yowhan Son

Turkish Journal of Agriculture and Forestry

Our study assessed how physiological traits and the growth of seedlings of Pinus densiflora and Larix kaempferi, representative coniferous species of Korea, are affected by warming and precipitation manipulation. A warming and precipitation manipulation experiment was conducted with 1- and 2-year-old seedlings using infrared heaters, transparent panels, and an irrigation system. Plant physiological activities were monitored using a portable photosynthesis measurement system, and seedling growth was investigated by measuring the dry weight of harvested biomass. P. densiflora, an isohydric species, showed an overall decrease in physiological activities under the warming treatment in the first (germination) year. In particular, stomatal conductance …


The Influence Of Burn Severity On Post-Fire Spectral Recovery Of Three Fires In The Southern Rocky Mountains, Jaclyn Guz, Florencia Sangermano, Dominik Kulakowski Jan 2022

The Influence Of Burn Severity On Post-Fire Spectral Recovery Of Three Fires In The Southern Rocky Mountains, Jaclyn Guz, Florencia Sangermano, Dominik Kulakowski

Geography

Increased wildfire activity and altered post-fire climate in the Southern Rocky Mountains has the potential to influence forest resilience. The Southern Rocky Mountains are a leading edge of climate change and have experienced record-breaking fires in recent years. The change in post-fire regeneration and forest resilience could potentially include future ecological trajectories. In this paper, we examined patterns of post-fire spectral recovery using Landsat time series. Additionally, we utilized random forest models to analyze the impact of climate and burn severity on three fire events in the Southern Rocky Mountains. Fifteen years following the fires, none of the burned stands …


Common Garden Study Reveals Frost-Tolerant, Generalist Northern Seed Sources Are Best Suited To Expand Range Of Quercus Rubra, Emily Lindback Jan 2022

Common Garden Study Reveals Frost-Tolerant, Generalist Northern Seed Sources Are Best Suited To Expand Range Of Quercus Rubra, Emily Lindback

Dissertations, Master's Theses and Master's Reports

Climate change is shifting the potential suitable range of northern red oak (Quercus rubra L.) faster than it can migrate, creating an adaptation lag. Quercus rubra is prominent in eastern North American forests and important for its carbon sequestration, ecological roles, and economic significance. Our study addresses which populations of Q. rubra are best suited for climatic conditions at the northern and central range limits. Our findings can inform forestry management policies such as assisted migration, where species are transferred within their native range to mitigate the effects of climate change. We planted over 800 Q. rubra seedlings …


Climate Adaptive Forest Management In The Northeastern Us: Social And Ecological Motivations, Barriers, And Responses Of Rural And Urban Foresters, Teresa Mcgann Jan 2022

Climate Adaptive Forest Management In The Northeastern Us: Social And Ecological Motivations, Barriers, And Responses Of Rural And Urban Foresters, Teresa Mcgann

Graduate College Dissertations and Theses

This project examines how foresters in a diversity of professional contexts perceive and respond to global change in the northeastern United States, with the goal of supporting foresters in broadening and deepening their use of climate adaptive strategies. Based on qualitative analysis of 32 in-depth semi-structured interviews with urban and rural foresters (n = 15 and n = 17, respectively) across New England and New York, a summary is presented of the i) important environmental drivers of adaptation; ii) commonly employed adaptive practices; iii) significant barriers to adaptation; and iv) approaches to working through named barriers. According to the motivations, …


Drought, Tree Mortality, And Regeneration In Northen California, Sophia Lb Lemmo Jan 2022

Drought, Tree Mortality, And Regeneration In Northen California, Sophia Lb Lemmo

Cal Poly Humboldt theses and projects

The 2012-2016 California drought was the most severe in the state’s recorded history, contributing to the death of millions of trees. While the effects of this drought on forests are relatively well studied in the central and southern Sierra Nevada, less is known about its effects on the heavily timbered and diverse forests of northern California. Through sampling 54 0.25 ha plots in northern California, this study compared tree mortality and regeneration patterns before, during, and after California’s most recent record-setting drought. This study evaluated 1) the influence of habitat and competitive covariates on mortality and regeneration trends using ridge …