Forest Sciences Commons^™

The Ecological Resilience Of A Tropical Montane Pine Forest To Droughts, Fire, And Hurricane Disturbance, Daniel Erland Brugger Swann

Electronic Theses and Dissertations

Owing to the geographic isolation and unique climatic conditions which occur in tropical montane forests (TMFs), these systems are highly sensitive to changes in both climate and disturbance. Therefore, as ongoing climate change alters disturbance regimes – potentially facilitating multiple disturbance interactions much greater than that of isolated disturbances – TMFs may be shifted to alternate stable states. However, study of TMF resilience is essentially unknown given the lack of long-term studies in these systems. We address the resiliency of the tropical montane pine forests of the Cordillera Central, Dominican Republic using long-term climate records, remeasured vegetation data, and reconstructed …

Effects Of Prescribed Fire On Drought Resistance And Recovery In Mixed Conifer Forests Of Lassen Volcanic National Park, California, Zachary J. Wenderott

Cal Poly Humboldt theses and projects

Forests throughout much of the western United States are experiencing increasing climatic variability, often resulting in decreased forest productivity and elevated likelihood of tree mortality. Severe drought, such California’s recent 2012-2015 drought, are projected to increase in intensity, frequency, and severity throughout much of this region in coming years. Forest management has long relied on prescribed fire and mechanical thinning to reduce fuel loads and ameliorate potential fire hazards. These treatments may also have the ability to reduce stand density, alleviate competitive pressures, and allow residual trees access to critical resources during periods of extreme stress. Utilizing a long-term National …

Inoculum Potential Of Pinus Edulis-Associated Ectomycorrhizal Fungi Across A Forest Extirpation Chronosequence, Annie M. Montes

Biology ETDs

Few studies have examined inoculum potential of ectomycorrhizal fungi (EMF) in the absence of plant hosts, yet persistence of these fungi may be paramount to resilience of Pinus edulis and other mycorrhizal plant species. We conducted a study in which seven sites were selected in northwestern New Mexico with known dates of P. edulis extirpation and a lack of regeneration. Age classes included: two sites extirpated 10-20 years ago, two extirpated 55-65 years ago, two extirpated 500+ years ago, and one extirpated 11,000+ years ago. At each site, two plots were paired: an extirpated plot and the nearest live adult …

Patterns For Populus Spp. Stand Biomass In Gradients Of Winter Temperature And Precipitation Of Eurasia, Vladimir Andreevich Usoltev, Baozhang Chen, Seyed Omid Reza Shobairi, Ivan Stepanovich Tsepordey, Viktor Petrovich Chasovskikh, Shoaib Ahmad Anees

Aspen Bibliography

Based on a generated database of 413 sample plots, with definitions of stand biomass of the genus Populus spp. in Eurasia, from France to Japan and southern China, statistically significant changes in the structure of forest stand biomass were found, with shifts in winter temperatures and average annual precipitation. When analyzing the reaction of the structure of the biomass of the genus Populus to temperature and precipitation in their transcontinental gradients, a clearly expressed positive relationship of all components of the biomass with the temperature in January is visible. Their relationship with precipitation is less clear; in warm climate zones, …

Tropical Understory Herbaceous Community Responds More Strongly To Hurricane Disturbance Than To Experimental Warming, Deborah K. Kennard, David Matlaga, Joanne Sharpe, Clay King, Aura M. Alonso-Rodríguez, Sasha C. Reed, Molly A. Cavaleri, Tana E. Wood

Michigan Tech Publications, Part 1

Ecology and Evolution published by John Wiley & Sons Ltd. The effects of climate change on tropical forests may have global consequences due to the forests’ high biodiversity and major role in the global carbon cycle. In this study, we document the effects of experimental warming on the abundance and composition of a tropical forest floor herbaceous plant community in the Luquillo Experimental Forest, Puerto Rico. This study was conducted within Tropical Responses to Altered Climate Experiment (TRACE) plots, which use infrared heaters under free-air, open-field conditions, to warm understory vegetation and soils + 4°C above nearby control plots. Hurricanes …

Potential Effects Of Climate Change On The Geographic Distribution Of The Endangered Plant Species Manihot Walkerae, Gisel Garza, Armida Rivera, Crystian Sadel Venegas Barrera, Jose Guadalupe Martinez-Avalos, Jon Dale, Teresa Patricia Feria-Arroyo

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

Walker’s Manihot, Manihot walkerae, is an endangered plant that is endemic to the Tamaulipan thornscrub ecoregion of extreme southern Texas and northeastern Mexico. M. walkerae populations are highly fragmented and are found on both protected public lands and private property. Habitat loss and competition by invasive species are the most detrimental threats for M. walkerae; however, the effect of climate change on M. walkerae’s geographic distribution remains unexplored and could result in further range restrictions. Our objectives are to evaluate the potential effects of climate change on the distribution of M. walkerae and assess the usefulness of natural protected areas …

A Comparison Of Fuel Reduction Methods For Wildfire Risk Management And Climate Change Resiliency In Mixed Conifer Forests In The Sierra Nevada, Heather Navle

Master's Projects and Capstones

Wildfires in the mixed conifer forests of California’s Sierra Nevada have been a common and natural disturbance for thousands of years, historically occurring every 3 to 30 years. The flora and fauna of the mixed conifer forest have evolved to depend on low to moderate severity wildfires for reproduction, foraging, and habitat. However, the Sierra Nevada has experienced dramatic environmental changes over the past ~150 years as a result of three main factors: wildfire suppression, climate change, and habitat loss. Because of the threat wildfires pose to human lives, property and timber harvest, they have been suppressed to an extent …

Drought In Temperate Mesic Regions Leads To Micro-Density Anomalies In White Pine, Elise Miller

CSB and SJU Distinguished Thesis

Wood density and wood volume determine the amount of carbon fixed by trees; however, while we are beginning to understand normal seasonal variation in wood density, anomalies are common, and their drivers are poorly understood. In conifers, wood density normally increases continuously throughout the season, but intra-annual fluctuations in wood density can occur and have been linked to climatic events. The causes of these fluctuations in density at the micro-scale (hereafter micro-density anomalies) are still debated.

Mesic regions are experiencing more droughts, but micro-density anomalies are rarely studied in these ecosystems. This study examined micro-density anomaly distribution within the boles …

Internet Of Things For Sustainable Forestry, Abdul Salam

Faculty Publications

Forests and grasslands play an important role in water and air purification, prevention of the soil erosion, and in provision of habitat to wildlife. Internet of Things has a tremendous potential to play a vital role in the forest ecosystem management and stability. The conservation of species and habitats, timber production, prevention of forest soil degradation, forest fire prediction, mitigation, and control can be attained through forest management using Internet of Things. The use and adoption of IoT in forest ecosystem management is challenging due to many factors. Vast geographical areas and limited resources in terms of budget and equipment …

Future Climate Change Will Have A Positive Effect On Populus Davidiana In China, Jie Li, Guan Liu, Qi Lu, Yanru Zhang, Guoqing Li, Sheng Du

Aspen Bibliography

Since climate change significantly affects global biodiversity, a reasonable assessment of the vulnerability of species in response to climate change is crucial for conservation. Most existing methods estimate the impact of climate change on the vulnerability of species by projecting the change of a species’ distribution range. This single-component evaluation ignores the impact of other components on vulnerability. In this study, Populus davidiana (David’s aspen), a tree species widely used in afforestation projects, was selected as the research subject under four future climate change scenarios (representative concentration pathway (RCP)2.6, RCP4.5, RCP6.0, and RCP8.5). Exposure components of range change as well …

Importance Of Tree-And Species-Level Interactions With Wildfire, Climate, And Soils In Interior Alaska: Implications For Forest Change Under A Warming Climate, Adrianna C. Foster, Amanda H. Armstrong, Jacquelyn K. Shuman, Herman H. Shugart, Brendan M. Rogers, Michelle C. Mack, Scott J. Goetz, K. Jon Ranson

Aspen Bibliography

The boreal zone of Alaska is dominated by interactions between disturbances, vegetation, and soils. These interactions are likely to change in the future through increasing permafrost thaw, more frequent and intense wildfires, and vegetation change from drought and competition. We utilize an individual tree-based vegetation model, the University of Virginia Forest Model Enhanced (UVAFME), to estimate current and future forest conditions across sites within interior Alaska. We updated UVAFME for application within interior Alaska, including improved simulation of permafrost dynamics, litter decay, nutrient dynamics, fire mortality, and postfire regrowth. Following these updates, UVAFME output on species-specific biomass and stem density …

Diffuse Light And Wetting Differentially Affect Tropical Tree Leaf Photosynthesis, Z. Carter Berry, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

‐Most ecosystems experience frequent cloud cover resulting in light that is predominantly diffuse rather than direct. Moreover, these cloudy conditions are often accompanied by rain that results in wet leaf surfaces. Despite this, our understanding of photosynthesis is built upon measurements made on dry leaves experiencing direct light.

‐Using a modified gas exchange setup, we measured the effects of diffuse light and leaf wetting on photosynthesis in canopy species from a tropical montane cloud forest.

‐We demonstrate significant variation in species‐level response to light quality independent of light intensity. Some species demonstrated 100% higher rates of photosynthesis in diffuse light …

Main And Interactive Effects Of Increased Precipitation And Nitrogen Addition On Growth, Morphology, And Nutrition Of Cinnamomum Burmanni Seedlings In A Tropical Forest, Jun Wang, Dafeng Hui, Hongfang Lu, Faming Wang, Nan Liu, Zhongyu Sun, Hai Ren

Biology Faculty Research

Global change such as altered precipitation patterns and increased atmospheric nitrogen (N) deposition will have significant impacts on seedling growth during plant recruitment. However, how interactive effects of increased precipitation and N deposition on forest seedling performance have not been well investigated. In this study, we conducted a two-year field experiment that manipulating precipitation amount (ambient rainfall and 25% increment during the wet season) and exogenous N addition (0 and 100 kg ha−1 yr−1) in a tropical secondary forest. Seedling growth, morphology and nutritional status of a dominant tree species (Cinnamomum burmanni) were measured. Results showed that increased precipitation had …

Guidelines For Aspen Restoration In Utah With Applicability To The Intermountain West, Stanley G. Kitchen, Patrick N. Behrens, Sherel K. Goodrich, Ashley Green, John Guyon, Mary O'Brien, David Tart

Aspen Bibliography

As highly productive and biologically diverse communities, healthy quaking aspen (Populus tremuloides; hereafter aspen) forests provide a wide range of ecosystem services across western North America. Western aspen decline during the last century has been attributed to several causes and their interactions, including altered fire regimes, drought, excessive use by domestic and wild ungulates, and conifer encroachment. Today’s managers need science-based guidance to develop and implement strategies and practices to restore structure, processes, and resilience to the full range of aspen functional types across multiple spatial scales. In these guidelines, we detail a process for making step-by-step decisions …

Drought And Freezing Vulnerability Of The Isolated Hybrid Aspen Populus X Smithii Relative To Its Parental Species, P. Tremuloides And P. Grandidentata, Nicholas J. Deacon, Jake J. Grossman, Jeannine Cavender-Bares

Aspen Bibliography

Aim

We assessed the vulnerability of an isolated, relictual Pleistocene hybrid aspen population of conservation interest (Populus x. smithii ) and the nearest populations of its parent species (Populus grandidentata and Populus tremuloides ) to springtime post‐bud break freezing and growing season drought stress. Response to these stressors in the three taxa was compared in terms of avoidance and tolerance.

Location

North American Midwest; USA.

Methods

Unique genets from the hybrid Niobrara River population and from the two parental populations were propagated in a common garden from rhizome cuttings. We tracked their phenology before and after bud break …

Warming Up: Climate Change Related Shifts Of Mycorrhizal Fungal Communities In High Latitude Ecosystems, Megan Rae Devan

Biology ETDs

This dissertation examines how climate change affects mycorrhizal fungal communities in boreal and arctic ecosystems. In chapter one, I revealed that increases in fire severity and related increases in deciduous tree dominance result in greater Ascomycota relative abundance (RA) and subsequent declines in Basidiomycota RA. In chapter two I analyzed the effects of post-fire mycorrhizal fungal communites on host growth. There were trends at the fungal genus level that were largely reflected at the guild level across all hosts; however, there were some fungal genera that had the opposite effect on different host species. In chapter three, I found host …

Beaver And Aspen: Synergy Among Keystone Species, Stephen N. Bennett, Nicolaas Bouwes, Paul C. Rogers

Aspen Bibliography

In the West, climate change is likely to increase the frequency, intensity, and duration of drought. Restoration of soils and water storage capacity can help create resilient uplands and riverscapes (i.e., streams and the valley bottoms). Over the past two centuries, common land uses, the removal of beaver and wood, straightening of streams, and damage to riparian areas have created simplified, structurally starved, riverscapes. Degraded streams are very efficient at transporting water, sediment, and nutrients downstream. Aspen forests are also biological hotspots that have been degraded by past land uses such as overbrowsing ungulates, land clearing, fire suppression, and outright …

Adaptation Strategies And Approaches For Forested Watersheds, P. Danielle Shannon, Christopher Swanston, Maria Janowiak, Stephen D. Handler, Kristen M. Schmitt, Leslie A. Brandt, Patricia Butler-Leopold

College of Forest Resources and Environmental Science Publications

Intentional climate adaptation planning for ecosystems has become a necessary part of the job for natural resource managers and natural resource professionals in this era of non-stationarity. One of the major challenges in adapting ecosystems to climate change is in the translation of broad adaptation concepts to specific, tangible actions. Addressing management goals and values while considering the long-term risks associated with local climate change can make forested watershed management plans more robust to uncertainty and changing conditions. We provide a menu of tiered adaptation strategies, which we developed with a focus on forests of the Midwest and Northeastern U.S., …

Climate Change, Woodpeckers, And Forests: Current Trends And Future Modeling Needs, Eric S. Walsh, Kerri T. Vierling, Eva Strand, Kristina Bartowitz, Tara W. Hudiburg

Aspen Bibliography

The structure and composition of forest ecosystems are expected to shift with climate‐induced changes in precipitation, temperature, fire, carbon mitigation strategies, and biological disturbance. These factors are likely to have biodiversity implications. However, climate‐driven forest ecosystem models used to predict changes to forest structure and composition are not coupled to models used to predict changes to biodiversity. We proposed integrating woodpecker response (biodiversity indicator) with forest ecosystem models. Woodpeckers are a good indicator species of forest ecosystem dynamics, because they are ecologically constrained by landscape‐scale forest components, such as composition, structure, disturbance regimes, and management activities. In addition, they are …

Iron (Oxyhydr)Oxides Serve As Phosphate Traps In Tundra And Boreal Peat Soils, Elizabeth M. Herndon, Lauren Kinsman-Costello, Kiersten A. Duroe, Jonathan Mills, Evan Kane, Stephen D. Sebestyen, Aaron A. Thompson, Stan D. Wullschleger

College of Forest Resources and Environmental Science Publications

Arctic and boreal ecosystems are experiencing pronounced warming that is accelerating decomposition of soil organic matter and releasing greenhouse gases to the atmosphere. Future carbon storage in these ecosystems depends on the balance between microbial decomposition and primary production, both of which can be regulated by nutrients such as phosphorus. Phosphorus cycling in tundra and boreal regions is often assumed to occur through biological pathways with little interaction with soil minerals; that is, phosphate released from organic molecules is rapidly assimilated by plants or microorganisms. In contrast to this prevailing conceptual model, we use sequential extractions and spectroscopic techniques to …

Increased Soil Temperature Stimulates Changes In Carbon, Nitrogen, And Mass Loss In The Fine Roots Of Pinus Koraiensis Under Experimental Warming And Drought, Seung Hyun Han, Seongjun Kim, Hanna Chang, Guanlin Li, Yowhan Son

Turkish Journal of Agriculture and Forestry

The effects of warming (+3 °C) and drought (-30% precipitation) on the fine root decomposition of Pinus koraiensis seedlings were examined using a litter bag method. The study site included a full factorial design with two temperature and two precipitation levels, with three replicates. Litter bags containing fine root litter of 2-year-old P. koraiensis seedlings were retrieved after 3, 6, and 12 months of decomposition. After 12 months, the mass loss of fine roots was significantly increased in response to warming (control = 31.1%, warming = 35.9%, drought = 29.2%, and warming plus drought = 35.5%); no change was observed …

Influence Of Climate Change And Prescribed Fire On Habitat Suitability And Abundance Of The High-Elevation Endemic Cow Knob Salamander (Plethodon Punctatus), Carl David Jacobsen

Graduate Theses, Dissertations, and Problem Reports (ETD)

Amphibians are facing global declines due to climate change, loss and degradation of habitat, invasive species, and disease. The Appalachian region of the eastern USA is a global biodiversity hotspot for salamanders, which are considered keystone species that influence nutrient dynamics in terrestrial and aquatic food webs. There are high rates of salamander endemism in the Appalachian region, with many species restricted to isolated, high elevation areas. The Cow Knob Salamander (Plethodon punctatus) is one such species. It is only found at elevations >675 m (most populations are above 900 m) on Shenandoah Mountain, North Mountain, and Nathaniel …

Reexamining The Utility Of Existing Climate Adaptation Frameworks Through Application On A Northern Forest, Alexander Rice

Dissertations, Master's Theses and Master's Reports

A review of the literature reveals the strengths and limitations of various climate adaptation frameworks and illuminates a general path by which a type of adaptation can be achieved. A number of useful frameworks exist but the number of independent case studies demonstrating the adaptation process in a detailed manner is much more limited. Additionally, components of the various adaptation processes can often seem vague and concepts such as adaptability ill-defined. For land managers approaching climate adaptation independently can be difficult, particularly in the areas of goal creation and vulnerability assessment. Within frameworks where user-defined adaptation goals dictate whether or …

Dependence Of Aspen Stands On A Subsurface Water Subsidy: Implications For Climate Change Impacts, D. M. Love, M. D. Venturas, J. S. Sperry, P. D. Brooks, J. L. Pettit, Y. Wang, W. R. L. Anderegg, X. Tai, D. S. Mackay

Aspen Bibliography

The reliance of 10 Utah (USA) aspen forests on direct infiltration of growing season rain versus an additional subsurface water subsidy was determined from a trait- and process-based model of stomatal control. The model simulated the relationship between water supply to the root zone versus canopy transpiration and assimilation over a growing season. Canopy flux thresholds were identified that distinguished nonstressed, stressed, and dying stands. We found growing season rain and local soil moisture were insufficient for the survival of 5 of 10 stands. Six stands required a substantial subsidy (31–80% of potential seasonal transpiration) to avoid water stress and …

Climate Change Adaptation Strategies And Approaches For Outdoor Recreation, Daniel O'Toole, Leslie A. Brandt, Maria K. Janowiak, Danielle Shannon, Patricia Leopold, Stephen D. Handler, Et Al.

Michigan Tech Publications, Part 1

Climate change will alter opportunities and demand for outdoor recreation through altered winter weather conditions and season length, climate-driven changes in user preferences, and damage to recreational infrastructure, among other factors. To ensure that outdoor recreation remains sustainable in the face of these challenges, natural resource managers may need to adapt their recreation management. One of the major challenges of adapting recreation to climate change is translating broad concepts into specific, tangible actions. Using a combination of in-depth interviews of recreational managers and a review of peer-reviewed literature and government reports, we developed a synthesis of impacts, strategies, and approaches, …

Compositional Response Of Amazon Forests To Climate Change, Adriane Esquivel-Muelbert, Timothy R. Baker, Kyle G. Dexter, Simon L. Lewis, Roel J.W. Brienen, Ted R. Feldpausch, Jhon Del Aguila-Pasquel, Et. Al.

Michigan Tech Publications, Part 1

Most of the planet's diversity is concentrated in the tropics, which includes many regions undergoing rapid climate change. Yet, while climate-induced biodiversity changes are widely documented elsewhere, few studies have addressed this issue for lowland tropical ecosystems. Here we investigate whether the floristic and functional composition of intact lowland Amazonian forests have been changing by evaluating records from 106 long-term inventory plots spanning 30 years. We analyse three traits that have been hypothesized to respond to different environmental drivers (increase in moisture stress and atmospheric CO 2 concentrations): maximum tree size, biogeographic water-deficit affiliation and wood density. Tree communities have …

Tamm Review: Reforestation For Resilience In Dry Western U.S. Forests, Malcolm P. North, Jens T. Stevens, David F. Greene, Michelle Coppoletta, Eric E. Knapp, Andrew M. Latimer, Christina M. Restaino, Ryan E. Tompkins, Kevin R. Welch, Rob A. York, Derek J.N. Young, Jodi N. Axelson, Tom N. Buckley, Becky L. Estes, Rachel N. Hager, Jonathan W. Long, Marc D. Meyer, Steven M. Ostoja, Hugh D. Safford, Kristen L. Shive, Carmen L. Tubbesing, Dana Walsh, Chhaya M. Werner, Peter Wyrsch, Heather Vice

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

The increasing frequency and severity of fire and drought events have negatively impacted the capacity and success of reforestation efforts in many dry, western U.S. forests. Challenges to reforestation include the cost and safety concerns of replanting large areas of standing dead trees, and high seedling and sapling mortality rates due to water stress, competing vegetation, and repeat fires that burn young plantations. Standard reforestation practices have emphasized establishing dense conifer cover with gridded planting, sometimes called 'pines in lines', followed by shrub control and pre-commercial thinning. Resources for such intensive management are increasingly limited, reducing the capacity for young …

Does Environment Filtering Or Seed Limitation Determine Post-Fire Forest Recovery Patterns In Boreal Larch Forests?, Wen H. Cai, Zhihua Liu, Yuan Z. Yang, Jian Yang

Forestry and Natural Resources Faculty Publications

Wildfire is a primary natural disturbance in boreal forests, and post-fire vegetation recovery rate influences carbon, water, and energy exchange between the land and atmosphere in the region. Seed availability and environmental filtering are two important determinants in regulating post-fire vegetation recovery in boreal forests. Quantifying how these determinants change over time is helpful for understanding post-fire forest successional trajectory. Time series of remote sensing data offer considerable potential in monitoring the trajectory of post-fire vegetation recovery dynamics beyond current field surveys about structural attributes, which generally lack a temporal perspective across large burned areas. We used a time series …

A Quantitative Analysis Of The Effects Of Urbanization, Mesophication And Prescribed Burns On Oak Woodlands In The Chicago Metropolitan Area, Chad Populorum

Celebration of Learning

Urban expansion has had devastating impacts on forest ecosystems, especially within the past century. Human attempts to dominate nature have diminished natural disturbance regimes, which have maintained the biodiversity and historic composition of these ecosystems. Fires have been a prominent force in maintaining the structure of oak, hickory and other heliophytic (sun loving and fire-adapted) forest systems. Human induced fire suppression has led to mesophication across North America. Mesophication is the transition from drier conditions with open canopies to wetter conditions with closed canopies. These new conditions decrease the survival rates of these important species and begin to favor mesophytic …

Changing Rainfall Frequency Rather Than Drought Rapidly Alters Annual Soil Respiration In A Tropical Forest, Qi Deng, Deqiang Zhang, Xi Han, Guowei Chu, Quanfa Zhang, Dafeng Hui

Biology Faculty Research

Tropical forests play an important role in global carbon (C) cycling due to high primary productivity and rapid litter and soil organic C decomposition. However, it is still unclear how changing rainfall will influence soil CO2 losses (i.e. via soil respiration) in tropical forests. Here, using a rainfall and litter manipulation experiment in a tropical forest, we show that enhanced litter-leached dissolved organic carbon (DOC) production with increased rainfall frequency drives substantial CO2 loss via soil respiration. A 50% increase in rainfall frequency (no change in total rainfall amount) enhanced inputs of DOC by 28%, total dissolved nitrogen (TDN) by …