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Reconstructing Stand-Age Structure In A Wet Miombo Woodland Using Dendrochronology, Zambia, Clara Tiyembekeze Zulu

All-Inclusive List of Electronic Theses and Dissertations

Dendrochronological research in tropical Africa has remained limited, leaving critical gaps in stand-age structure and climate-growth relationships in seasonally dry tropical woodlands. This study reconstructed stand-age structure and assessed climate sensitivity in the wet Miombo woodland of African Explosives Limited (AEL) forest, Copperbelt Province, Zambia. Field sampling was conducted during four African Dendrochronology Fieldschools (2021-2024) using a Modified Variable Area Transect (MVAT) design across nine plots. The series intercorrelation was 0.351; the average mean sensitivity was 0.423. The oldest tree was 170 years old, and more than 70% of the sampled species showed potential for dendrochronology. Markhamia obtusifolia was the …

Great Graminoids! Quantifying Vegetation On Roan’S Western Balds Over The Last 80 Years (1936, 1956, 2016), James T. Donaldson

Faculty Open Access Works

PowerPoint originally presented at Friends of Roan Mountain Winter Naturalists' Rally 11 Feb. 2017.

Grant funding from Friends of Roan Mountain for resampling historic transects from Carvers Gap to Grassy Ridge. Revised 2021, 2022, & 2023 (technical features and diversity); edited for clarity 2026 (for written rather than oral presentation & added references slide).

Species Distribution Modeling Of Parasitic Corpse Flower Rafflesia Arnoldii Var. Arnoldii R. Br Related To Host’S Fractional Photosynthetically Active Radiation In Tanggamus, Sumatra, Indonesia, Andriwibowo Andriwibowo, Suyud Utomo

Jurnal Penelitian Kehutanan Wallacea

Corpse flower, or scientifically known as Rafflesia arnoldii var. arnoldii R.Br, is one of the species that is endemic to Sumatra, Kalimantan and Java Island. As a parasitic plant, this species depends on its tree host species. While the host species depends on environmental variables include Fractional Photosynthetically Active Radiation (FAPAR), forest covers, and elevation for its growth. Then those variables were important to develop the Species Distribution Modelling (SDM) of R. arnoldii using the MaxEnt technique. One of the important regions for R. arnoldii in Sumatra is Tanggamus in Lampung, and currently, information about suitable habitats for R. arnoldii …

Urban Bird Community Interaction With Ficus And Non-Ficus Tree, Eka Alifikri, Yeni Aryati Mulyani, Ani Mardiastuti

Jurnal Penelitian Kehutanan Wallacea

Ficus trees are recognised as keystone species in forest ecosystems and are crucial for urban wildlife, especially birds. IPB Darmaga Campus, a biodiversity-rich urban area, hosts a variety of plant species, including Ficus and non-Ficus tree species, along with diverse bird species. This study aimed to compare the utilisation of Ficus and non-Ficus plants by birds in the area. Observations were conducted on 5 Ficus benjamina, 5 Ficus microcarpa, and 10 non-Ficus tree individuals. Ficus trees were used by 15 bird species from 12 families, with 1700 recorded interactions. In contrast, non-Ficus trees were …

Ecological Studies Of Wolves On Isle Royale, Sarah R. Hoy, Rolf O. Peterson, John A. Vucetich

Ecological Studies of Wolves on Isle Royale

Annual Report 2025-2026

Assessing Tree Species Diversity In Forests Using Combined Remote Sensing Data, Tufan Demi̇rel

Turkish Journal of Agriculture and Forestry

Tree species diversity (TSD) is a critical biological variable for ecosystem functioning and sustainable forest management.This study aimed to model TSD in forest ecosystems using spectral and texture metrics extracted from Sentinel-2, WorldView-3,and PlanetScope satellite imagery, and structural metrics derived from LiDAR data. Tree species data collected through field surveyswere used to calculate Shannon, Simpson, and species richness biodiversity indices. These biodiversity indicators were then related toexplanatory variables derived from remote sensing (RS) metrics. The Boruta algorithm was applied for variable selection and randomforest regression analysis was used for modeling. The results show that combining LiDAR and satellite data is …

Effects Of Conifer Encroachment On Oregon White Oak Crown Structure And Nonvascular Epiphyte Communities, Courtney Jonell Copper

Cal Poly Humboldt theses and projects

Oregon white oak (Quercus garryana, QUGA) is an ecologically and culturally important broadleaf tree species native to northern California and the Pacific Northwest. Fire suppression and subsequent encroachment by Douglas-fir (Pseudotsuga menziesii, PSME) and other conifers have made QUGA woodlands among the most threatened habitat types in the region. This study examines the influence of conifer encroachment on QUGA crown structure and nonvascular epiphyte (NVE) communities using ground- and crown-based sampling techniques.

Twenty-four trees were sampled across four sites in northern California along a gradient of conifer encroachment that was quantified as PSME basal area (BA). A …

Green Connectivity In Metropolitan Jabodetabek: Climate Change And The Challenge Of Urban Forest, Safira Maharani Putri, Hendricus Andy Simarmata

CSID Journal of Infrastructure Development

Urban areas in Indonesia, particularly the Greater Jakarta metropolitan region (Jabodetabek), are increasingly experiencing the adverse effects of climate change, such as the Urban Heat Island (UHI) phenomenon. Rapid urbanization has contributed significantly to rising greenhouse gas emissions and deteriorating environmental quality. Urban forests are one of the key solutions to mitigate these impacts; however, their spatial distribution in Jabodetabek remains suboptimal and poorly connected. This study uses NDVI as a proxy for urban forest density, where “urban forest” refers to vegetated areas within cities as defined by Presidential Regulation No. 60/2020. The research addresses the following question: How has …

Baseline Assessment Of Insect Biodiversity And Distribution In La Salle Botanical Gardens, Pampanga, Philippines, Amir Lyndon Gavriell C. Beup, Kaleela Euan G. Jayson, Alyssa Ira Z. Tan, Ronielle Elisha S. Pascual, Alexi Gabrielle S. Henson, Esperidion Josef P. Ladao Iii, Juan Carlo T. Gumangan

Sinaya: A Philippine Journal for Senior High School Teachers and Students

Insects are crucial for ecosystem functions, such as pollination and food web maintenance. This study aims to assess insect biodiversity in La Salle Botanical Gardens (LSBG) in Porac, Pampanga, focusing on its grassland and forestland areas. Using rapid biodiversity assessment, this study provides baseline data on insect diversity, abundance, dominance, and evenness for conservation. Sampling employed transect line intercept and quadrat methods. Specimens were collected using different collection and preservation techniques. Insects (n = 184) were collected from August to October 2024, with specimens (n = 46) belonging to seven insect orders in the grassland and specimens (n = 138) …

The Effect Of An Invasive Species (Lantana Camara) And A Fast-Growing Herb (Acanthus Pubescens) On The Plant And Animal Communities In Kibale National Park, Uganda, Kathleen Bufka

Theses and Dissertations

Fast-growing plant species, like Lantana camara and Acanthus pubescens, could threaten biodiversity in Kibale National Park, Uganda. I surveyed plants and wildlife in areas where these plants were frequently encountered compared to those areas where they are infrequent. I found mixed results based on plant traits and the animals considered. My findings support management efforts on these two species to prevent forest degradation.

Integrating Belowground Recovery Into Tropical Forest Restoration Design And Monitoring, Lauren Toro, Leland K. Werden, Shalom D. Addo-Danso, Kelly M. Andersen, Sarah Batterman, Matilde M. Bragadini, Pooja Choksi, Rebecca J. Cole, Liza S. Comita, Daniela Cusack, Daisy H. Dent, Lee H. Dietterich, Joshua B. Fisher, Katrin Fleischer, Lucia Fuchslueger, Nohemi Huanca-Nunez, Janey R. Lienau, Lindsay A. Mcculloch, Ember M. Morrissey, Jennifer S. Powers, Mareli Sánchez-Juliá, Oscar Valverde-Barrantes, Anita Weissflog, Michelle Y. Wong

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

There is growing recognition that tropical forest restoration is key for sequestering carbon and enhancing ecosystem resilience. Soils, roots, and soil biota are central to ecosystem function and services, but belowground recovery is largely overlooked in restoration monitoring frameworks. Here, we outline current understanding of the links between above- and belowground recovery in tropical forests by examining how belowground properties before and after intervention influence recovery; by evaluating whether aboveground recovery can serve as a proxy for belowground dynamics; and by proposing a blueprint for monitoring dynamic soil physical (bulk density, aggregate stability), chemical (organic matter or carbon, pH), and …

Pollinator Plant Communities Within Restored Montane Longleaf Pine Ecosystems, Hanen Van Rossem

Master's Theses

Historically the fire-dependent and biodiverse longleaf pine (Pinus palustris) ecosystem was the dominant ecosystem of the Southeastern US. This ecosystem’s range was massively reduced due to land conversion and fire exclusion, causing the decline of many native species. Efforts to restore and protect longleaf pine stands are now ongoing with the goal of expanding habitat and refuge for threatened species. Differences in restoration practices and prior land use may influence the extent to which restored habitat patches can support pollinators and their plants. This study compared pollinator plant biodiversity between restored neighboring montane longleaf pine stands that differed in …

Ecological Studies Of Wolves On Isle Royale, Sarah R. Hoy, John A. Vucetich, Rolf O. Peterson

Ecological Studies of Wolves on Isle Royale

Annual Report 2024-2025

Impacts Of Southern Pine Beetle (Dendroctonus Frontalis Zimmerman) On Loblolly Pine (Pinus Taeda L.) Canopy And Water Use In The Homochitto National Forest, Mississippi, Usa, Sasha Goodnow, Yun Yang, Hui Liu, Ashley Schulz

Endeavors: Mississippi State Undergraduate Research Journal

Abiotic and biotic forest disturbances can have many impacts to forest ecosystem services, including to forest water use. Studies on impacts to forest evapotranspiration have been conducted on the mountain pine beetle (Dendroctonus ponderosae) in western North America, but not on the southern pine beetle (Dendroctonus frontalis), which is a native pest of loblolly pine (Pinus taeda) and shortleaf pine (Pinus echinata), in the southeastern United States. Stressed pine trees produce pheromones that attract southern pine beetles and, with enough stressed trees, beetle populations can quickly grow to epidemic levels and attack healthy trees, which results in widespread tree mortality. …

Machine Learning And Uass For Managing Autumn Olive (Elaeagnus Umbellata) On Reclaimed Surface Mines, Sean Michael Keane

Graduate Theses, Dissertations, and Problem Reports (ETD)

This research introduces an innovative approach for managing autumn olive (Elaeagnus umbellata) on reclaimed surface mines through the integration of machine learning algorithms and unmanned aerial systems. The proliferation of autumn olive presents significant ecological challenges on disturbed landscapes, necessitating more efficient detection and control methods. This study evaluated Random Forest classification and deep learning approaches using the U-Net architecture for identifying autumn olive across four phenological stages using high-resolution imagery. The RGB U-Net model achieved F1-scores of 0.927, 0.912, and 0.871 for autumn olive detection during peak, late, and senescence stages respectively, outperforming both multispectral and vegetation …

Firelog: An Open-Source, Low-Cost System For Temperature Logging During Wildland Fires With High Spatial And Temporal Resolution, Nipuna Chamara, Yufeng Ge, Sabrina E. Russo

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Measuring flame, air, and soil temperatures during wildland fires, including wildfires and controlled burns in land management contexts, is crucial for research and applications in fire ecology, safety, and management in a wide array of ecosystems, from grasslands to forests. However, open-source and commercial systems are needed for measuring and logging flame and air temperatures that are user-friendly, economical, modular, and customizable. This paper details the design, development, and validation of the FireLog system. Laboratory validation experiments demonstrated high measurement accuracy, with a minimum coefficient of determination (R2) of 0.98 and the highest observed root mean square error (RMSE) of …

Spatial Analysis Of American Chestnut (Castanea Dentata) Distribution And Ecology In Kentucky’S Federal Lands, Jacob Raymond Pease

Murray State Theses and Dissertations

Anthropogenic factors have been the cause of the decline of tree species across the globe. From unsustainable logging and development to disease and improper management, threats to forests have taken their toll. The American chestnut (Castanea dentata) was once an integral basal tree species in Appalachian forests, but chestnut blight drove the species to functional extinction by the mid-1900s. The recent creation of genetically modified chestnuts gives hope for future restoration of the species throughout its historical range. Despite blight resistance, effective restoration will require optimal site selection for finding and planting chestnuts, which will maximize limited resources. …

Wildlife Distribution Mapping And Analysis In Gorongosa National Park, Mozambique, Using Site And Satellite Imagery Data, Pinho Joaquim Munhequeira Mr

Murray State Theses and Dissertations

One of Mozambique's most important conservation sites, Gorongosa National Park has seen critical ecological changes over the past several decades resulting from climate variability, habitat loss, and political instability. This research integrates Geographic Information Systems (GIS) and remote sensing to examine the relationship between vegetation dynamics and wildlife population, and distribution. The main goals of this study are to evaluate the spatial distribution of particular wildlife species: buffalo (Syncerus caffer), elephant (Loxodonta africana), hippopotamus (Hippopotamus amphibius), and zebra (Equus quagga), and determine the impact of vegetation density and land cover on their …

Condition And Management Futures In A Quaking Aspen Recreation Area. Final Report To Snyderville Basin Special Recreation District, Paul C. Rogers, Georgie Corkery, Anna B. Miller

Aspen Bibliography

In partnership with Snyderville Basin Special Recreation District (SBSRD), we undertook a study of ecological conditions and user preferences within a quaking aspen recreational destination forest. The location, in two sections know as Run-A-Muk and Right Turn Sage (RAM/RTS), has experienced some forest die-off in the principally aspen dominated forest dissected by ski, bike, and hiking trails. Graduate student Georgie Corkery led the study and successfully completed a Master's degree, in addition to providing needed information to SBSRD regarding the status, uses, and preferred actions at this facility. Key outcomes regarding aspen conditions include assigning causal factors—ungulate browsing and elevated …

Historical Fire And Forest Structure In Western Dry Forests: Alternative Models, Controversies, And Management Plan Revision, Gordon Steinhoff

William & Mary Environmental Law and Policy Review

Management plan revision is currently underway for national forests in the Sierra Nevada Mountains of California, the Pacific Northwest, and other regions of the country under the U.S. Forest Service’s 2012 Planning Rule. With respect to dry ponderosa pine and mixed-conifer forests in the Sierra Nevada and Pacific Northwest, agency scientists and others claim that these forests were historically open and parklike, with primarily large, well-distributed trees, few smaller trees, and sparse underlying vegetation, leaf litter, and woody debris. Large, high-severity fire was rare. Fire exclusion since the early 1900s has led to the “densification” of these forests and unnatural …

Vertebrate Diversity In The La Amistad International Park Buffer Zone, Guadalupe, Chiriqui, Panamá, Mina Olson

Independent Study Project (ISP) Collection

Forest fragmentation and increasing agricultural land use are posing threats to the diversity of vertebrates in Panama and across the Mesoamerican Biological Corridor. Protected areas are crucial for providing connectivity and maintaining vertebrate populations. For endemic species with small native ranges, these protected areas are critical for their survival due to sensitivity of habitat change. Higher species diversity and occupancy has been reported for both birds and mammals in protected and forested areas. This pilot survey of vertebrate species was conducted to determine which species live in a primary forest within the buffer zone of La Amistad International Park near …

Ecological Studies Of Wolves On Isle Royale, Sarah Hoy, Rolf O. Peterson, John Vucetich

Ecological Studies of Wolves on Isle Royale

Annual Report 2023-2024

An Ecological Analysis Of The Elevational Gradient Effect On Mushroom Community Diversity Near Andasibe, Madagascar, Zoe Garver

Independent Study Project (ISP) Collection

The effect of elevational gradients on biodiversity has been widely studied in the field of ecology (Rahbek, 1995). The evidence supports a trend for highest biodiversity at mid latitudes and decreasing biodiversity as elevation increases (Rahbek, 1997; Grytnes, 2003; Hariharan and Buckley, 2022). This effect has primarily been explained by variation of temperatures and resource availability at different elevations. However, the effect that elevation plays on fungal communities is relatively underrepresented in the literature (Dahlberg, 2001). This study analyzes changes in mushroom diversity across an elevational gradient in Mitsinjo Reserve and Analamazaotra National Park found in Madagascar. Using the Braun-Blanquet …

Effects Of Timber Harvest On Understory Vegetation Succession: A Time Series Study, Reese A. Poindexter, Trevor Weeks, Chad Bishop, Akasha Faist

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Timber harvest, as a necessary and common global practice, can significantly affect the ecosystems being harvested through opening the canopy, disturbing the understory, and resetting successional trajectories. This study examined how timber harvest influenced understory plant functional group dominance, understory species richness, and understory species dominance along a 40-year, or older, harvest timeline across two forest types (mesic and xeric) in Northwestern Montana, U.S.A. In our two forest types, vegetation sampling was completed at 208 sites with 1,040 quadrats across six timber-harvest timelines. Harvest timelines varied from the most recent at 1-5 years post-harvest to over 40 years as the …

Aboveground Biomass Density Estimation Using Deep Learning: Insight From Neon Ground-Truth Data And Simulated Gedi Waveform, Ashish Mahaur

Dissertations, Master's Theses and Master's Reports

Accurately estimating Aboveground Biomass Density (AGBD) is crucial for managing Earth's carbon cycle and informing climate strategies. NASA's GEDI mission advances global forest mapping, but traditional linear models often yield less reliable AGBD estimates. This study enhances AGBD estimation using deep learning models with NEON ground-truth data and simulated GEDI waveforms. We compared 1D CNNs, LSTMs, and pre-trained CNNs to traditional models. The ResNet152 model outperformed linear regression, achieving an R² of 0.68, demonstrating a 17% improvement. Our experiments also demonstrate the importance of large, diverse datasets, particularly for training deep learning models.

Human Dimensions Of Woody Encroachment Management In Nebraska, Emily Rowen

School of Natural Resources: Dissertations, Theses, and Student Research

Woody plant encroachment (WPE) is a social-ecological problem that will challenge conservation professionals and agricultural producers to adapt their management strategies. This research first examined WPE from the perspective of individual conservation professionals through an online survey. Conservation professionals’ attitudes about adaptation to vegetation transitions, such as WPE, were of interest because these attitudes are one measure of how prepared this group is to respond to WPE. Hypothesized predictors of adaptation attitude were tested through linear regression modeling. These predictors included ecological change, observation of WPE, or risk perception. It was found that risk perception was the strongest predictor of …

Ecological Change And Livestock Governance In A Peruvian National Park, Kenneth R. Young, Eyner Alata, Rodney Chimner, Randall B. Boone, Gillian Bowser, Laura Bourgeau-Chavez, Beatriz Fuentealba, Jessica Gilbert, Javier A. Ñaupari, Molly H. Polk, Sigrid Resh, Cecilia Turin, Melody Zarria-Samanamud

Michigan Tech Publications

While the grazing of livestock has occurred for millennia in the Andes, current sustainability debates center on concerns with co-managing climate change and pastoralism. These discussions have special resonance in places protected by the state for biodiversity, scenery, and sustainable and traditional land uses, such as those found in protected areas and biosphere reserves. For this article, we integrate data from a social-ecological research project on the land use systems that affect high-elevation ecosystems in Peru’s Huascarán National Park, with special emphasis on the wetlands. We used land cover and land use data and insights from interactions with pastoralists to …

Bryophyte (Sl) Growth And Environmental Factors Along An Altitudinal Gradient On Cerro Gaital, El Valle, Coclé, Panamá, Julian Grace-Martin

Independent Study Project (ISP) Collection

Research on bryophytes (SL) in the tropics has been lacking compared with the high number of species found there and the potential benefit of bryophytes (SL) as indicators of pollutants and other forms of human disturbance. This study investigated whether or not bryophyte (SL) growth patterns showed relation when compared with environmental factors on the mountain Cerro Gaital in El Valley, Panamá. Whether or not bryophytes (SL) are present, extent of the area covered by their growth, and height of their growth are all aspects of bryophyte (SL) growth that were used. In this study, these three aspects are compared …

Bison Alter The Northern Yellowstone Ecosystem By Breaking Aspen Saplings, Luke E. Painter, Robert L. Beschta, William J. Ripple

Aspen Bibliography

The American bison (Bison bison) is a species that strongly interacts with its environment, yet the effects of this large herbivore on quaking aspen (Populus tremuloides) have received little study. We documented bison breaking the stems of aspen saplings (young aspen > 2 m tall and ≤ 5 cm in diameter at breast height) and examined the extent of this effect in northern Yellowstone National Park (YNP). Low densities of Rocky Mountain elk (Cervus canadensis) after about 2004 created conditions conducive for new aspen recruitment in YNP's northern ungulate winter range (northern range). We sampled …

The Far-Reaching Effects Of Genetic Process In A Keystone Predator Species, Grey Wolves, Sarah Hoy, Philip W. Hedrick, Rolf O. Peterson, Leah Vucetich, Kristin Brzeski, John A. Vucetich

Michigan Tech Publications

Although detrimental genetic processes are known to adversely affect the viability of populations, little is known about how detrimental genetic processes in a keystone species can affect the functioning of ecosystems. Here, we assessed how changes in the genetic characteristics of a keystone predator, grey wolves, affected the ecosystem of Isle Royale National Park over two decades. Changes in the genetic characteristic of the wolf population associated with a genetic rescue event, followed by high levels of inbreeding, led to a rise and then fall in predation rates on moose, the primary prey of wolves and dominant mammalian herbivore in …