Forest Sciences Commons^™

The Core Of It All: From The Forest To The Concrete Jungle, Ayo Andra J. Deas

Dissertations, Theses, and Capstone Projects

The Core of It All is a component of principle within Fasaha. The mission of Fasaha is to implement programming directed toward development of one’s Core through self-actualization. Self-Actualization is defined as bringing forth the total essential qualities of one’s own consciousness, character, and identity through positive behavior. Throughout this manuscript, principle is defined as the standard of natural essential qualities determining intrinsic consciousness, character and identity. Programming is defined as providing with intrinsic instructions for the automatic performance of a task.

Fasaha is a support service that enhances the existing organization’s service. Throughout this dissertation, it will be apparent …

Celestial Bodies, Rebecca L. Rand, Mark Popinchalk

Capstones

Most of us will never come close to touching space. But space touches us every day. On Celestial Bodies, journalist Rebecca Rand and astronomer Mark Popinchalk explore the ways outer space interacts with life on earth.

In Episode 1, hosts Rebecca Rand and Mark Popinchalk explore how, for millions of years, trees have been recording celestial events in space. Within the rings of their trunks, trees store radiation from solar flares, supernovae, and changes in the earth’s magnetic field. The hosts talk to Dr. Ben Pope to learn more about what we can discover by looking at radioactive molecules …

Fine Characterization Of Leafing Phenology In The Brazilian Atlantic Forest By Optical And Microwave Remote Sensing, James B. Bell

Dissertations and Theses

Tropical forests provide important ecosystem functions in the global biosphere, but they remain among the most poorly understood elements of land surface models, especially with regard to their seasonal dynamics. For instance, in seasonally dry forests, the pattern of the annual green-up in their canopies closely follows annual patterns of rainfall. The same, however, does not occur in wet forest canopies which are dominated by evergreen trees. In the latter, water is not scarce enough to limit leaf photosynthetic function. Canopy leafing phenology in these forests is therefore poorly characterized by optical remote sensing methods which are not sensitive to …

Nutrient Dynamics And Ecosystem Development Of Urban Forests, Gisselle A. Mejía

Dissertations, Theses, and Capstone Projects

Urban growth and expansion are a major component of global environmental change, with impacts on climate, air and water quality, biodiversity, and human well-being. Forests embedded in urban landscapes are critical in mitigating these impacts at local, regional, and continental scales. However, assessing urban forests is difficult because cities are heterogenous in physical, chemical, biological, and social dimensions. This heterogeneity has constrained how urban forests are defined, and therefore, how they are studied. The objective of this dissertation is to determine how these biophysical and social factors drive ecological processes in urban forests and will address three outstanding challenges in …

Quantifying Aboveground Biomass In A Tropical Forest Using A Lidar Waveform Weighted Allometric Model, Alejandro Rojas

Theses and Dissertations

Our knowledge of the distribution and amount of terrestrial above ground biomass (AGB) has increased using lidar technology. Recent advancements in satellite lidar has enabled global mapping of forest biomass and structure. However, there are large biases in satellite lidar estimates which impacts our understanding of carbon dynamics, particularly in tropical forests.

Ni-Meister et al. (2022) developed a lidar full waveform weighted height-based allometric model which produced very good results in temperate deciduous/conifer forest in the continental US. The purpose of this study was to evaluate this biomass model in an African tropical forest using the Land Vegetation and Ice …

Technical Note: Novel Estimates Of The Leaf Relative Uptake Rate Of Carbonyl Sulfide From Optimality Theory, Georg Wohlfahrt, Albin Hammerle, Felix M. Spielmann, Florian Kitz, Chuixiang Yi

Publications and Research

In order to estimate the gross primary productivity (GPP) of terrestrial ecosystems from the canopy uptake of carbonyl sulfide (COS), the leaf relative uptake rate (LRU) of COS with respect to carbon dioxide needs to be known a priori. Currently, the variability of the LRU between plant species in different biomes of the world is poorly understood, making the choice of an appropriate LRU uncertain and hampering further progress towards developing COS as an alternative tracer of GPP. Here we propose a novel approach for estimating LRU based on plant optimality principles, validate it against in situ leaf gas exchange …

Satellite Evidence Of Canopy-Height Dependence Of Forest Drought Resistance In Southwestern China, Peipei Xu, Wei Fang, Tao Zhou, Hu Li, Xiang Zhao, Spencer Berman, Ting Zhang, Chuixiang Yi

Publications and Research

The frequency and intensity of drought events are increasing with warming climate, which has resulted in worldwide forest mortality. Previous studies have reached a general consensus on the size-dependency of forest resistance to drought, but further understanding at a local scale remains ambiguous with conflicting evidence. In this study, we assessed the impact of canopy height on forest drought resistance in the broadleaf deciduous forest of southwestern China for the 2010 extreme drought event using linear regression and a random forest (RF) model. Drought condition was quantified with standardized precipitation evapotranspiration index (SPEI) and drought resistance was measured with the …

The Effects Of Late Spring Frost On Forest And Landscape Health And Recovery Of The Black Rock Forest, New York, Caroline Eco, Oliver Imhans, Aaron Davitt, Andrew B. Reinmann

Publications and Research

Projected changes in climate are expected to increase the frequency of late spring frost events in the Northeast US. Such events can be harmful to trees because freezing temperatures that occur after leaf-out can damage or kill young leaves. The resultant defoliation typically forces a second flush of leaves, but delays canopy development, which in turn delays the onset of canopy carbon uptake and alters canopy thermal properties. In this study, we analyzed a recent freeze event that occurred on 8-9 May 2020 (DOY 129-130) at Black Rock Forest (BRF), which is in the Hudson Highlands of southeastern New York …

Variation In Personality Among Semi-Wild Myanmar Timber Elephants, Sateesh Venkatesh

Theses and Dissertations

This study examines two personality traits: exploration and neophobia, which could influence human-elephant conflicts. Thirty-one semi-wild elephants were tested over two trials using a custom novel puzzle tube containing three tasks and three rewards. Our studies show that elephants do vary significantly between individuals in both exploration and neophobia.

Microbial Diversity In Urban Environments: Concern For Antibiotic Resistance, Ality Aghedo, Mangala Tawde, Nazrul I. Khandaker

Publications and Research

We are almost oblivious to the presence of microorganisms in our daily lives, but they exist and come into contact with us all the time. While some bacteria are harmless, and even beneficial, other bacteria can cause infections. A common treatment to bacterial infections is antibiotics and the success of an antibiotic depends on the resistance of the bacteria to the antibiotic. We conducted experiments to identify the types of bacteria that can be found on surfaces or within soil environments that come into contact with a vast number of people on a daily basis and how this can affect …

Walking As Ontological Shifter: Thoughts In The Key Of Life, Bibi (Silvina) Calderaro

Dissertations, Theses, and Capstone Projects

With walking as ontological shifter I pursue an alternative to the dominant modernist episteme that offers either/or onto-epistemologies of opposition and their reifying engagements. I propose this type of walking is an intentional turning towards a set of radical positions that, as integrative aesthetic and therapeutic practice, brings multiplicity and synchronicity to experience and being in an expanded sociality. This practice facilitates the conditions of possibility for recurring points of contact between the interiority perceived as ‘body’ and the exteriority perceived as ‘world.’ While making evident the self’s at once incoherence with it-self, it opens to a space beyond the …

A Global Study Of Gpp Focusing On Light-Use Efficiency In A Random Forest Regression Model, Suhua Wei, Chuixiang Yi, Wei Fang, George Hendrey

Publications and Research

Light-use efficiency (LUE) is at the core of mechanistic modeling of global gross primary production (GPP). However, most LUE estimates in global models are satellite based and coarsely measured with emphasis on environmental variables. Others are from eddy covariance towers with much greater spatial and temporal data quality and emphasis on mechanistic processes, but in a limited number of sites. In this study, we conducted a comprehensive global study of tower-based LUE from 237 FLUXNET towers, and scaled up LUEs from in situ tower level to global biome level. We integrated the tower-based LUE estimates with key environmental and biological …

Exploring Data Mining Techniques For Tree Species Classification Using Co-Registered Lidar And Hyperspectral Data, Julia K. Marrs

Theses and Dissertations

NASA Goddard’s LiDAR, Hyperspectral, and Thermal imager provides co-registered remote sensing data on experimental forests. Data mining methods were used to achieve a final tree species classification accuracy of 68% using a combined LiDAR and hyperspectral dataset, and show promise for addressing deforestation and carbon sequestration on a species-specific level.

Stably Stratified Canopy Flow In Complex Terrain, Xiyan Xu, Chuixiang Yi, Eric Kutter

Publications and Research

Stably stratified canopy flow in complex terrain has been considered a difficult condition for measuring net ecosystem–atmosphere exchanges of carbon, water vapor, and energy. A long-standing advection error in eddy-flux measurements is caused by stably stratified canopy flow. Such a condition with strong thermal gradient and less turbulent air is also difficult for modeling. To understand the challenging atmospheric condition for eddy-flux measurements, we use the renormalized group (RNG) k–ε turbulence model to investigate the main characteristics of stably stratified canopy flows in complex terrain. In this two-dimensional simulation, we imposed persistent constant heat flux at ground surface and linearly …

Tipping Point Of A Conifer-Based Ecosystem Under Severe Drought, Kaicheng Huang, Chuixiang Yi, Donghai Wu, Tao Zhou, Xiang Zhao, William J. Blanford, Suhua Wei, Hao Wu, Du Ling, Zheng Li

Publications and Research

Drought-induced tree mortality has recently received considerable attention. Questions have arisen over the necessary intensity and duration thresholds of droughts that are sufficient to trigger rapid forest declines. The values of such tipping points leading to forest declines due to drought are presently unknown. In this study, we have evaluated the potential relationship between the level of tree growth and concurrent drought conditions with data of the tree growth-related ring width index (RWI) of the two dominant conifer species (Pinus edulis and Pinus ponderosa) in the Southwestern United States (SWUS) and the meteorological drought-related standardized precipitation evapotranspiration index …