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Publication MOLECULAR CHARACTERIZATION AND ASSESSMENT OF NUTRIENT AND SALINITY TREATMENTS ON SELECTED VEGETABLE AND MEDICINAL PLANTS(2024-05) Mady, EmadIn addition to being a significant source of food, vegetable plants are abundant in vitamins and other indispensable nutrients. The use of medicinal plants also results in the production of natural remedies and safe medications. Using underutilized genetic resources and employing environmentally responsible crop production methods are two ways that food security can be improved. Adopting environmentally friendly methods that use agricultural practices or local genetic resources is essential to boost food production. To improve both the quality and quantity of the yield, this study conducts this research using compounds that occur naturally, studying seeds native to the area, and enriching the soil with microorganisms that promote plant growth. Pumpkin, Cucurbita moschata Duchesne, is a crucial crop belonging to the cucurbit family and is cultivated in nearly all arable regions worldwide. Germplasm identification plays an essential role in connecting the conservation and utilization of crop genetic resources in various plant breeding activities. The current study focuses on the biochemical and molecular variations among a group of pumpkin genotypes sourced from different climatic zones. The resulting information can enhance the management of germplasm and the sustainable utilization of neglected genotypes. Local landraces of pumpkins have successfully developed some environmental adaption to the environment, displaying various traits that provide resistance against diseases and tolerance to environmental stressors. Institutional efforts towards producing improved and high-quality registered vegetable seeds using local germplasm have concentrated on utilizing unexploited landraces in preliminary studies for developing breeding programs. Hence, the study findings might provide valuable insights into the chemical phenotypic characterization and effective planning and selection of parent plants for potential pumpkin breeding programs designed for trait improvement. The Asteraceae family is divided into 13 subfamilies. These subfamilies include Asteroideae, Barnadesioideae, and Cichorioideae. The lack of comprehensive research on various genera and representative species has hindered the understanding of the phylogeny and diversification of the daisy family (Asteraceae). Chicory and endive have been cultivated since ancient times in Egypt and are now essential elements in Mediterranean diets. Both chicory and endive are now grown all around the world, especially in the Mediterranean region. The genus Cichorium includes two recognized and distinct species according to provenance; C. intybus L. (chicory) and C. endivia L. (endive). In the genus Cichorium, the European flora denoted the species; C. intybus, C. spinosum, and C. endivia, and subdivided the species endivia into two subspecies. These two subspecies include one species that is cultivated (endivia), while the second is wild (divaricatum). Salinity stress is a significant concern in crop production, which has a significant impact on global food security. Agronomic practices offer mitigation options for managing salt stress. Eggplant (Solanum melongena L.) is a prominent summer crop in Egypt and worldwide because its fruit contains a relatively rich content of vitamins, protein, and minerals, along with carbohydrates. The primary objective of eggplant growers, both domestically and internationally, is to enhance the productivity of high-quality eggplants. The irrigation water source is a crucial factor impacting plant development and productivity. With the rising scarcity of freshwater, using drainage water is suggested as one of the recommended solutions for irrigating eggplants. Salinity causes various structural changes that alter the water balance in plants and poses a serious environmental challenge to crop production. Photoprotectants are strongly advised for improving growth and enhancing the yield productivity of various plants when exposed to abiotic stress conditions. Salicylic acid is essential in protecting plants from both biotic and abiotic stresses. Exogenously application of salicylic acid has been reported to affect various plant processes, such as stomatal closure, cell membrane permeability, and ion uptake, along with photosynthetic rate. This includes the content of pigments, growth rate, and fruit yield. Cowpea, or Vigna unguiculata, in the Leguminosae family, is a traditional staple food source of sustenance for humans. The cultivation of cowpea is gaining attention due to its high nutritional value and ability to survive in dry soils, as well as its potential to improve soil fertility for forthcoming crop plants. Growth-promoting microorganisms, which include Plant Growth-Promoting Rhizobacteria (PGPRs), can be employed for sustainable farming because of their capacity for nitrogen fixation and also their ability to produce growth-regulating plant hormones. A mixture of soil microbial inoculants commonly enhances plant growth more efficiently than individual inoculants due to the synergistic effects of different strains, which complement each other's positive traits. The literature shows that integrated biofertilizers have been studied less in cowpea plants. This study addresses the need to evaluate the effect of inoculating cowpea plants with growth-promoting microorganisms, specifically B. amyloliquefaciens, yeast (S. cerevisiae), and cyanobacteria (N. mucorum), as potential biofertilizers for cowpeas. The study also examines the impact of using these microorganisms in combination. Fennel (Foeniculum vulgare Mill.), a member of the Apiaceae family, is an herbaceous medicinal and aromatic plant that is indigenous to the Mediterranean basin. Globally, fennel fruits, foliage, and bulbs are used medicinally and as vegetables. The fruit (also seed) of the fennel plant is valued for their essential oil (EO), which has shown effectiveness against several diseases and conditions. These diseases include cancer, bacterial infections, fungal infections, antithrombosis, hepatoprotection, and inflammation. In fennel fruits, the essential oil level may vary anywhere in the range of 1% and 4%, depending on several factors such as the cultivar, the fruit age, the climatic conditions, and the farming techniques. Trans-anethole and estragole along with fenchone and limonene are considered the major compounds in fennel essential oil that determine the oil quality. When following the organic farming approach, chemical fertilizers are primarily avoided. Organic farming, including bio-fertilizer applications, is used as an alternative approach to deliver plant nutrients and at the same time to maintain agricultural ecosystems. Microorganisms employed in this biofertilization system can fix nitrogen, dissolve soil-phosphorus and potassium, form molecules that can enhance plant growth in general and improve the defense system against diseases and stressors. In organic agricultural production, natural supplies of vital plant nutrients are provided via processed biofertilizers and manure, among other natural organic additions. Among the many advantages of organic fertilization are enhanced soil health, preservation of soil fertility due to its ability to replenish lost organic matter, mitigation of environmental harm while maintaining productivity, reaching the goal of sustainable agricultural production, and reduction of the risks associated with excessive fertilization and groundwater contamination.Publication BIOGEOCHEMICAL DYNAMICS OF MINERAL-ORGANIC ASSOCIATIONS IN THE RHIZOSPHERE(2024-05) Garcia Arredondo, MarielaMineral-organic associations (MOAs) can protect organic carbon compounds against microbial or enzymatic attack for centuries to millennia, representing one of the most important terrestrial carbon storage mechanisms globally. Consequently, current carbon models assume that, once formed, MOAs and carbon protected therein are relatively inert to environmental disturbance. However, plant roots and associated microbes in the rhizosphere have a well-known ability to biogeochemically transform minerals. This dissertation aimed to resolve the mechanisms and environmental controls regulating the biogeochemical dynamics of MOAs in the rhizosphere. Using custom-designed rhizoboxes combined with microsensors and high-resolution mass spectrometry, we found that functionally distinct metabolites (namely sugars and organic acids) shape the EH and pH dynamics along single roots. Rhizodeposition and the ensuing EH and pH dynamics are controlled by root development and can create biogeochemically distinct and transient microenvironments in the rhizosphere (Chapter 2). Combining rhizobox experiments with reactive transport modelling, we further showed that diel biogeochemical oscillations in the rhizosphere caused by diel patterns in root-carbon release have the potential to create and disrupt MOAs (Chapter 3). Using isotopically labelled MOAs in a growth chamber experiment, we further showed that MOAs destabilization was proportional to root growth irrespective of environmental conditions, but that that the efficacy by which roots destabilized MOAs (per root biomass) increased with nitrogen limitations (Chapter 4). Combined, these findings underscore the dynamic nature of MOAs in the rhizosphere and the potential vulnerability to destabilization of MOAs because of the biogeochemical dynamics in the rhizosphere arising from root development, plant growth, diel cycling, or nutrient limitations. Our work suggests that the stability MOAs, and thus carbon persistence, is not solely dictated by the inherent strength of mineral-organic interactions. Rather, MOA stability is intricately regulated by soil-plant feedback mechanisms responsive to physiological and environmental changes. Understanding these dynamics and their drivers will facilitate the development of holistic management practices that address both climate change mitigation and soil health maintenance.Publication Factors Affecting the Biology of a Montane Breeding Bird, the Swainson's Thrush (Catharus ustulatus)(2024-05) Deckel, Sarah C.Montane breeding birds experience a range of challenges that may limit their breeding biology, such as colder temperatures and increased precipitation at higher elevations. The continuing effects of climate change are causing shifts in biotic and abiotic factors that may compound these threats to montane bird species, who may be faced with the opposing pressures of adverse climatic conditions at higher elevations and increased predation at lower elevations. This dissertation focused on a representative montane breeding bird, the Swainson’s Thrush (Catharus ustulatus) within the White Mountains, New Hampshire, USA and examined how these shifting factors along an elevational gradient influenced their breeding biology. In my first chapter, I evaluated temperature and rain with daily nest survival rate of thrush nests and found that heavier rain events (cumulative rain accrued per day in millimeters) and warmer temperatures at higher elevations, respectively, negatively affected nest survival of this species. In chapter 2, I used stable isotope analysis and estimated the proportion of dietary prey items within the diet of adult birds. This revealed thrushes at lower elevations consumed more high protein invertebrates, such as beetles and spiders, and higher elevation birds consumed primarily lower protein millipedes. In chapter 3, I deployed several automated recording units along an elevational gradient and recorded singing male birds to determine when birds established territory. I found adult thrushes established territory 6 days earlier at higher elevations, and birds established territory 6 days earlier in 2020 than in 2019. Finally, in chapter 4, I evaluated the insulation value of thrush nests and found nests at higher elevations were more insulated. However, when considering the presence of mature nestlings (> 6 days old), this negatively affected insulation value of nests, suggesting that older nestlings may compress and affect the insulative integrity of nests. Additionally, nests that were built with more twigs were poorly insulated and likely more porous, potentially aiding in better airflow and allowing nests to dry efficiently in wetter conditions. This research provides further understanding of the breeding biology of montane birds within a warming climate and suggests that increasing temperatures and more frequent rain events will have severe negative consequences on several important stages of their breeding season.Publication Survival of American Kestrels Across Eastern North America and Investigations Into Overlooked Drivers of the Continental Population Decline(2024-05) Melo, Mercedes LThe American Kestrel, a small falcon species found throughout North America, was once regarded as a common sight in both agricultural and grassland habitats. Since the 1970’s, kestrel abundance has declined in Christmas Bird Counts, Breeding Bird Surveys, and migration counts. While this decline has attracted the attention of many researchers, the driver, or drivers, of this population trend still remains unknown. While much attention has been paid to reproduction, another key life history trait, survival, has received relatively little consideration. Proper survival estimation provides key population demographic information that is essential to understanding potential drivers of population trends. Additionally, survival estimation throughout the full annual cycle and across geographical regions allows researchers to pinpoint when and where mortality occurs and, therefore, where resources should be allocated for potential mitigation and conservation action. This project provides known-fate survival estimates throughout the full annual cycle and within geographically disparate regions, including data on both adult and juvenile American Kestrels. This data is a vast improvement upon our current knowledge of kestrel survival and can help orient future research and conservation efforts towards areas and stages of increased mortality. In the search for potential drivers of the population decline, some drivers have seemingly been “ruled out” due to assumptions about kestrels and their interactions with their environment. In multiple publications, predation of kestrels by Cooper’s hawks has been regarded as an unlikely cause of the kestrel’s population decline, despite Cooper’s hawks being known to predate kestrels and our knowledge of Cooper’s hawk’s increasing population trends that are concurrent with the kestrel’s declining population trends. As these studies focused on the impacts of direct predation by Cooper’s hawks on kestrels, effectively showing that predation events occur too scarcely to limit kestrel populations, they entirely overlooked the nonconsumptive impacts of these species interacting. This project employs an experimental playback framework to simulate the presence of a Cooper’s hawk within a kestrel’s breeding territory. This simulation allows for evaluation of nonconsumptive impacts of Cooper’s hawks on kestrel behavior, nestling development, and survival post-fledge, which this study suggests are all impacted by the Cooper’s hawk presence. Due to their adaptability, habitat change, particularly in the form of urbanization, has also been effectively excluded as a potential cause of the American Kestrel’s decline. Kestrels are currently considered suburban adaptable, suggesting that the species is able to adapt to urbanization and thrive in human-dominated landscapes. While some kestrels live in cities and suburban areas full-time, this title veils the impacts of increased human disturbance, collisions with man-made structures, alterations in prey abundance, and exposure to human-associated toxins on those individuals that are not adapted to these environments. Overwintering migratory individuals may be impacted even more severely by urbanization as they are not necessarily adapted to urban conditions at any other point in their annual cycle. This study investigated the effects of urbanization on American Kestrel abundance and sex ratios by surveying overwintering populations annually in a rapidly urbanized region. Using this long-term dataset provided insight into kestrel population demographics before, during, and after human development, which elucidated that kestrel populations decreased and became more male-dominated in response to urbanization.Publication Causes and Consequences of Tree Mortality from Invasive Insects(2024-05) Barker Plotkin, Audrey AInvasions of non-native insects are a major driver of change for forest composition, structure, and carbon storage capacity, especially in invasion hotspots such as the Northeastern United States. The goal of this dissertation is to understand causes and quantify consequences of tree mortality from invasive insects. The two insect-host systems featured – spongy moth (Lymantria dispar) defoliation of oaks (Quercus), and hemlock woolly adelgid (Adelges tsugae) infestation of eastern hemlock (Tsuga canadensis) – exhibit contrasting virulence and magnitude of ecosystem change. The three chapters of the dissertation each addressed a different question and approach. Chapter 1 examined the carbon starvation hypothesis by evaluating sugar and starch stores in oak trees defoliated by spongy moth. Defoliated trees drew down their sugar and starch stores, sometimes to zero. All the trees that died had extremely low energy reserves (<1.5% dry weight of sugars and starches in their roots and stems), providing empirical evidence that these trees starved to death. Chapter 2 evaluated the longer-term (15 years) results from an experimental manipulation that contrasted hemlock death from simulated insect damage with salvage logging. Many differences between the treatments either converged within 15 years or are projected to converge within the next decade, with notable exceptions of understory species richness, dead wood quantity, and aboveground carbon stocks. The differences that persist provide the girdled plots with greater biodiversity, aboveground carbon stocks, and dead wood microhabitats, and thus a potentially greater capacity for resilience to ongoing and future stressors and disturbances. Finally, Chapter 3 contrasted spongy moth outbreaks in the 1980s and the 2010s across a forested landscape and asked how defoliation and forest stand development interact to determine oak mortality. Greater loss of trees and biomass occurred during the 2010s outbreak than the 1980s outbreak, partially because the average tree that died between 2010-2020 was larger and contained much more biomass than the average tree that died between 1980-1990. However, other stressors likely contributed as well, highlighting an increased risk of tree mortality in an era of accelerating global change. Taken together, this work highlights how invasive insects alter forested ecosystems and reduce their capacity to respond to human needs and climate change.Publication Uncertainty in Climatic Change Impacts on Multiscale Watershed Systems(2013-09) Tsvetkova, Olga V.Uncertainty in climate change plays a major role in watershed systems. The increase in variability and intensity in temperature and precipitation affects hydrologic cycle in spatial and temporal dimensions. Predicting uncertainty in climate change impacts on watershed systems can help to understand future climate-induced risk on watershed systems and is essential for designing policies for mitigation and adaptation. Modeling the temporal patterns of uncertainties is assessed in the New England region for temperature and precipitation patterns over a long term. The regional uncertainty is modeled using Python scripting and GIS to analyze spatial patterns of climate change uncertainties over space and time. The results show that the regional uncertainty is significant in variation for changes in location and climatic scenarios. Watershed response to climate change under future scenarios is assessed using hydrologic simulation modeling for the Connecticut River watershed. Changes in water budgets are assessed for each of the subbasins using spatial analysis and process modeling using GIS and Soil and Water Assessment tool (SWAT). The results show that climate change uncertainty in precipitation and temperature can lead to uncertainty in both quantity and quality in the watershed system. A spatiotemporal, dynamic model was applied to subbasins within the Chicopee River Watershed to estimate climate change uncertainty impacts at a micro scale. These changes were assessed relative to changes in land use and climatic change. The results show that there is a significant potential for climate change to increase evaporation, watershed runoff and soil erosion rates and this varied with climate change uncertainty. Finally, water sustainability gradient analysis was applied to the Volga River watershed in Russia to assess potential climate change impacts by combining with downscaled Global Circulation Model estimates and spatial assessment. Results show that runoff and evapotranspiration are projected to increase with potential for more localized floods and drought events effecting both water resources and food supply. Overall results show that climate change uncertainty can impact watershed systems and spatial and temporal assessments is important for developing strategies for adaptation to climatic change conditions at local and regional scales.Publication Ecohydrologic Impacts of Climate and Land Use Changes on Watershed Systems: A Multi-Scale Assessment for Policy(2013-09) Ekness, Paul A.Maintaining flows and quality of water resources is critical to support ecosystem services and consumptive needs. Understanding impacts of changes in climate and land use on ecohydrologic processes in a watershed is vital to sustaining water resources for multiple uses. This study completes a continental and regional scale assessment using statistical and simulation modeling to investigate ecohydrologic impacts within watershed systems. Watersheds across the continental United States have diverse hydrogeomorphic characters, mean temperatures, soil moistures, precipitation and evaporation patterns that influence runoff processes. Changes in climate affect runoff by impacting available soil moisture, evaporation, precipitation and vegetative patterns. A one percent increase in annual soil moisture may cause a five percent increase in runoff in watersheds across the continent. Low soil moisture and high temperatures influence runoff patterns in specific regions. Spring runoff is increased by the influence Spring soil moisture, Winter and Spring evaporation, and Winter and Spring evaporation. Spring runoff is decreased by increases in Winter and Spring temperatures and increases in the vegetation index. Winter runoff is affected by maximum vegetative index, temperature, soil moisture, evaporation and precipitation. Contributing factors to runoff are influenced by geomorphic and seasonal variations requiring strategies that are site-specific and use system-wide information. Regional scale watershed analysis investigates the influence of landscape metrics on temporal streamflow processes in multiple gauged watersheds in Massachusetts, U.S.A. Time of concentration, recession coefficient, base flow index, and peak flow are hydrologic metrics used to relate to landscape metrics derived using FRAGSTAT software. Peak flow increases with increasing perimeter-area fractal dimensions, and Contagion index and decreases as Landscape Shape Index increases. There was an increasing trend in the fractal dimension over time indicative of more complex shape of patches in watershed. Base flow index and recession coefficient fluctuated from low to high decreasing recently. This could be indicative of open space legislation, conservation efforts and reforestation within the state in the last ten years. Coastal systems provide valuable ecosystem services and are vulnerable to impacts of changes in climate and continental land use patterns. Effects of land use and climate change on runoff, suspended sediments, total nitrogen and total phosphorus are simulated for coastal watersheds around the Boston Bay ecosystem. The SWAT (Soil and Water Assessment Tool) model, a continuous-time, semi distributed, process-based model, is used to simulate the watershed ecohydrologic process affecting coastal bodies. Urbanization in watersheds increased runoff by as much as 80% from the baseline. Land use change poses a major threat to water quality impacts affecting coastal ecosystems. Total nitrogen increased average of 53.8% with conservative changes in climate and land use. Total phosphorus increased an average of 57.3% with conservative changes in land use and climate change. Climate change alone causes up to 40% increase in runoff and when combined with a 3.25% increase in urban development runoff increased an average of 114%. Coastal ecosystems are impacted by nutrient runoff from watersheds. Continued urbanization and changes in climate will increase total nitrogen, total phosphorus and suspended sediments in coastal ecosystems. Continental scale runoff is affected by soil moisture and vegetative cover. Cover crops, low tillage farm practices and natural vegetation contribute to less runoff. Developing policies that encourage protection of soil structure could minimize runoff and aid in maintaining sustainable water resources. Best Management Practices and Low impact development at the national level with continued stormwater legislation directed towards sustainable land use policy will improve water quantity and quality. Fragmentation observed in Massachusetts increases the number of urban parcels and decreases the size of forested areas. Faster runoff patterns are observed but recent land management may be changing this runoff pattern. Municipal and state zoning ordinance to preserve open space and large forest patches will restrict urban growth to specific regions of a watershed. This could improve quantities of water available to ecosystems. Increases in total nitrogen, phosphorus and suspended sediments to coastal ecosystems can be minimized with use of riparian buffers and Best Management Practices within coastal watersheds. Urbanization and climate change threatens coastal ecosystems and national policy to preserve and restrict development of coastal areas will preserve coastal ecosystem services.Publication Fisher Population Ecology on the Hoopa Valley Indian Reservation, Northwestern California(2012-05) Matthews, Sean MichaelI studied aspects of fisher (Martes pennanti) population ecology on the Hoopa Valley Indian Reservation in northern California to fill critical information gaps relative to timber management and its effect on the status of fishers, a candidate for listing under the U.S. Endangered Species Act. A decline in mark-resight density estimates of fishers from 1998 (52/100 km2; 95% CI = 43-64) to 2005 (14/100 km2; 13-16) was likely due to changes in prey habitat suitability, increased predation pressure, and/or disease. The decline was also indicated by catch-per-unit effort indices, but not by camera station or track-plate station indices. Colleagues and I developed and tested methods of collecting mark-recapture data using genetic marking, passive integrated transponder (PIT) tag technology, and digital, passive-infrared photography that could be used in a demographic monitoring protocol. The comparatively high cost of PIT tag reading equipment and genetic analyses makes the use these methods dramatically more expensive and yield less demographic data compared to using a traditional mark-recapture approach using only live trapping. By monitoring 40 radio-marked, breeding age (> 2 years old) females during 2005-2011, we found that 87% exhibited denning behavior and 65% of these were successful in weaning at least one kit (mean = 1.9). Of 14 kits radio-marked in their first fall, 3 died prior to dispersal, 3 lost collars, and the other 8 established home ranges 0.8-18.0 km away from natal areas. Nipple size (width multiplied by height of the largest anterior nipple), evaluated as a predictive index of female fisher reproductive success, differed among nonbreeders vs. attempted and current breeders. A predictive index for use in assigning reproductive status to females with unknown reproductive histories had an overall correct classification rate of 81% and a chance-corrected measure of prediction of 69.5%. These results illustrate the value in establishing long-term, accurate programs to monitor populations of imperiled species which strive to determine cause and affect relationships to changes in populations and ultimately, modeling habitat fitness. The relatively low reproductive rate of female fishers brings into question the species ability to demographically respond to increased rates of juvenile and adult mortality with increased reproduction and/or survival. The limited dispersal capability of juvenile fishers restricts ability to rescue vanishing local populations from extirpation, re-inhabit landscapes from which they were previously extirpated, and establish the functional connectivity of metapopulations.Publication Finding Blame for Environmental Outcomes: A Cognitive Style Approach to Understanding Stakeholder Attributions, Attitudes, and Values(2011-09) Hawkins, Christopher ThomasThis study sought to connect two bodies of knowledge--integrative complexity and attribution theory. Integrative complexity is a term that indicates the simplicity vs. complexity of a person's mental frame and perceptual skill. A person who perceives nuance and subtle differences typically scores higher on an integrative complexity measure. Attribution theories are concerned with how individuals perceive causation for various events. The limited research into the linkages between perceived causation for an event and how complexly a person thinks about the domain of that event, coupled with the dearth of attribution research in the natural resource management literature, inspired this research. Florida Keys coral reef users were sent a mail questionnaire between July 2009 and March 2010. Integrative complexity level was determined using an index that was developed for this research. Based on attributional and cognitive complexity literature, it was hypothesized that people who score lower in integrative complexity would exhibit an "external" attribution pattern. Integrative complexity was also proposed to influence: attitude and value extremity; number of perceived problem causes; and use of mediated communication. Finally, it was hypothesized that individuals will assign more blame to other groups than to their own. Six of the study's seven null hypotheses were rejected: 1) a significant relationship was found between integrative complexity level and the number of causes that respondents recorded for the decline of the Florida Keys reef ecosystem, 2) significant differences were observed in attitude extremity according to integrative complexity, 3) significant differences were observed in value orientation according to integrative complexity, 4) significant differences were observed in value extremity according to integrative complexity level, 5) significant differences were observed in mediated communication according to integrative complexity level, and 6) significant differences were observed in blame pattern according to group affiliation. Only one null hypothesis was not rejected: no support was found for a connection between integrative complexity and attribution style. These results indicate support for the integrative complexity index, though work to refine the measure seems in order. Additional recommendations for future research include investigating new approaches to examining the relationship between integrative complexity and attribution style.Publication Improving Conservation Efforts Through a Better Understanding of Forest Elephant Ecology, the Impacts of Threats on Elephants and Freshwater Fisheries in Northern Congo(2016-09) Boundja, Roger PatrickIMPROVING CONSERVATION EFFORTS THROUGH A BETTER UNDERSTANDING OF FOREST ELEPHANT ECOLOGY, THE IMPACTS OF THREATS ON ELEPHANTS AND FRESHWATER FISHERIES IN NORTHERN SEPTEMBER 2016 ROGER PATRICK BOUNDJA, B.Sc. FORESTRY, MARIEN NGOUABI UNIVERSITY, BRAZZAVILLE MSc. UNIVERSITY OF CAPE TOWN PhD. UNIVERSITY OF MASSACHUSETTS AMHERST Directed by: Professor Curtice R. Griffin Catch data, including fish numbers, length-weight were collected during a multi-mesh Gillnet fisheries-independent survey in 2007-2008, and fisheries-dependent mixed gear surveys in 2009-2010 and 2015 across 400km stretch of the Sangha River located in the Sangha Tri-National. Overall, very high species richness (Chao 2 mean=250, SD=16.15) and diversity index (Simpson Inverse Mean=43.72, SD=0.02) estimates suggesting that the Sangha River mainstream could host one of the highest freshwater fish diversity across the region. Overall, Canonical Correspondence Analysis (CCA) suggested a high total variance in species data, of which significant proportions explained by environmental variables. Latitude and distance to park borders had the strongest importance in ordination, and fishes tended to avoid high human-disturbed areas near large towns and high water turbidity. A special focus was further put into 7 fish species, recognized for their economic value in local fisheries. Catch Per Unit Effort (CPUE) and contribution in local fisheries were computed for the 7 species for main fishing techniques. Overall, significantly highest average CPUE was found in wet season months, and set Gillnets appeared the most efficient but were mainly targeting small-size and immature fishes and therefore not a sustainable fishing technique. Extrapolations from otolith readings suggested that an overwhelming majority of harvested fishes were estimated to be only a few months old, under their age-at first maturity. Finally, Classification And Regression Tree (CART) of the same 7 focal species’ CPUE suggested that Citharinus gibbosus was the most important species, predicted with at least 55% chance in Set Gillnets, followed by Mormyrops anguilloides with at least 64% chance in basket-traps. Overall, during a 5-year seasonal camera survey carried out at the core-area of a nearly pristine Nouabalé-Ndoki National Park in Northern Congo, camera trap sites were occupied by elephants nearly 82% of weeks but elephant occupancy was not affected by any of environmental variables in the model. However, detection probability was 0.182, and significantly affected by percentage of Gilbertiodendron Dewevrei mono-dominant forest, mixed closed canopy forest, and number of sampling days. Large elephant social groups were detected near forest clearings or “bais”.Publication A Period Examination Through Contemporary Energy Analysis of Kevin Roche‚Äôs Fine Arts Center at University of Massachusetts-Amherst(2016-09) Fiocchi, L Carl; Fiocchi, L. CarlStudies of buildings belonging to a subset of Modernist architecture, Brutalism, have included discussions pertaining to social and architectural history, critical reception, tectonic form and geometry inspirations, material property selections, period technology limitations, and migration of public perceptions. Evaluations of Brutalist buildings‚Äô energy related performances have been restricted to anecdotal observations with particular focus on the building type‚Äôs poor thermal performance, a result of the preferred construction method, i.e. monolithic reinforced concrete used as structure, interior finish and exterior finish. A valid criticism, but one that served to dismiss discussion that the possibility of other positive design strategies limiting energy consumption, while simultaneously maintaining occupant comfort, existed in these buildings. The University of Massachusetts-Amherst Fine Arts Center (FAC) designed by Pritzker Prize winning architect Kevin Roche, was the Brutalist building used to develop an evaluation protocol that will serve as a template for energy and/or occupant comfort dissections and evaluations of other Brutalist buildings. A calibrated (ANSI/ASHRAE Standard 140) and validated energy model (DesignBuilder) was programed with all requisites, i.e. geo-position, ordinal orientation, building geometry, envelope materiality, construction details, local weather and climate, program activities, mechanical systems, occupancy schedules, etc. All inputted data was synchronized and consistent with the first year of the building‚Äôs occupancy, 1976. Analyses using the DesignBuilder model and an Autodesk Ecotect Analysis model were performed with results relating to thermal performance of the envelope, daylight harvesting, glare control, siting advantage, solar defense via self-shading, material solar absorptance impacts, thermal mass, and wind related strategies documented. Results demonstrated and quantified the inadequacy of the thermal envelope and the positive presence of daylight harvesting, glare control, and solar defense via self-shading. Results also suggest the possibility of material solar absorptance strategies, thermal mass strategies, and wind harvesting strategies. The FAC‚Äôs EUI, as determined from the models above and a potential EUI determined from a FAC model inputted with a single energy efficiency measure (improvement of thermal envelope) was compared with EUI data from ‚ÄúCBECS, 2012 Table C5‚Äù. This perspective and insight into the building‚Äôs reality, within the context of energy performance and occupant comfort, cleared the haze of anecdotal evidence.Publication Evaluating resistance surfaces for modeling wildlife movement and connectivity(2016-09) Zeller, KatherineThe continued growth of human populations and associated development in many areas of the world is causing persistent fragmentation of natural habitats. In response, wildlife corridors are often promoted as essential for the conservation of wildlife species. Wildlife corridors allow for the movement of individuals between habitat patches and confer many benefits including the maintenance of metapopulations and metapopulation dynamics, the maintenance of seasonal migratory routes, genetic exchange, and the potential for individuals and populations to shift their ranges in response to climate change. Wildlife corridors are modeled across a resistance-to-movement surface where resistance represents the willingness of an organism to cross a particular environment, the physiological cost of moving through a particular environment, or the reduction in survival for the organism moving through a particular environment. Resistance surfaces can be estimated using a wide variety of methods yet, to date, there has been no in-depth methodological comparison of these methods and their appropriateness for modeling connectivity. My dissertation has two main objectives. The first was to determine the sensitivity of species-habitat models, resistance surfaces and corridors for pumas (Puma concolor) in southern California to six key factors: (1) data type used (point, step, or path data); (2) Statistical models employed; (3) Behavioral state of the individuals; (4) Spatial scale of analysis; (5) GPS collar acquisition interval; and (6) Thematic resolution and richness of the underlying geospatial layers. The second objective was to determine which combination of factors results in the most appropriate resistance surfaces for connectivity modeling. I found that species-habitat models, resistance surfaces and corridors were extremely sensitive to all six of these factors – to the point where using one scale versus another or one data type versus another resulted in conflicting conclusions about habitat use and differences in the location of corridors. I recommend that, for modeling movement and corridors, path data be used in a context-dependent multi-scale modeling framework. I also recommend that many different geospatial layers at different thematic resolutions be examined to identify the most appropriate landscape definition for the species and study area of interest.Publication Regional Recruitment Dynamics and Seasonal Ecology of Juvenile Bluefish (Pomatomus Saltatrix)(2016-09) Stormer, David GRecruitment in fishes, defined as the survival of a cohort through the first year of life, can be highly variable and affected by small changes in biological and physical factors. Much of the historical focus into the sources of recruitment variability has concentrated on the larval stage, but recent attention has shifted to the relatively longer juvenile period. Spawning behavior that results in the production of multiple cohorts over time and space within a year-class may dampen recruitment variability by decreasing natural mortality risk. The bluefish (Pomatomus saltatrix) is a migratory marine species that produces multiple cohorts of offspring during annual spawning migrations. Juvenile bluefish are among the fastest growing fish in the ocean. Consequently, bluefish is one of the few species that both mature and enter the fishery shortly after its first birthday, so recruitment success may be particularly critical in determining year-class strength. The following dissertation explores the factors that influence recruitment potential of bluefish. The first chapter provides a brief history of the study of recruitment in fisheries science and an introduction to bluefish life history. Chapter two investigates the interaction between the juvenile bluefish cohorts in the Hudson River estuary prior to the autumn migration. Chapter three presents the discovery of the northern Florida coastal ocean as an essential habitat to juvenile bluefish during the winter. The final chapter provides a summary of the main conclusions from chapters two and three.Publication Evaluating Digital VHF Technology to Monitor Shorebird and Seabird Use of Offshore Wind Energy Areas in the Western North Atlantic(2016-09) Loring, Pamela HInformation on offshore movements of high priority bird species is needed for monitoring and managing adverse effects of offshore wind energy development in the western North Atlantic Ocean. This information is particularly important at night and during periods of inclement weather when risks of collision with offshore wind turbines may be elevated. For small-bodied avian taxa, technologies for monitoring movements of individually-marked birds are limited since satellite-based devices are still too heavy (> 5 g) for use on birds weighing < 150 g. In this dissertation, I evaluate the use of light-weight (1 to 1.5 g) digital VHF transmitters and a network of automated radio telemetry stations for tracking shorebirds and seabirds in offshore areas. In Chapter One, I compare digital VHF telemetry with satellite telemetry for tracking a shorebird, the American Oystercatcher (Haematopus palliatus), at nesting areas in coastal Massachusetts. In Chapter Two, I evaluate possible adverse effects and retention time of using a glue and suture method for attaching digital VHF transmitters to the inter-scapular region of Common Terns (Sterna hirundo), a small-bodied seabird. In Chapter Three, I analyze data on the movements of digital VHF-tagged Common Terns and Arctic terns (Sterna paradisaea) from four colonies throughout the western North Atlantic Ocean to assess the utility of this technology for tracking birds at regional scales. In Chapter Four, I examine movements of digital VHF-tagged Common Terns from two colonies in southern New England shelf region of the U.S. Atlantic relative to Wind Energy Areas in state and federal waters. The aim of this chapter is to evaluate the use digital VHF telemetry for tracking terns across offshore Wind Energy Areas and to relate offshore movement events to temporal (time of day, calendar date), atmospheric (wind speed, precipitation rate, visibility) and demographic (sex, nesting colony) covariates associated with assessments of collision risk. Through these studies, I evaluate the safety and effectiveness of using digital VHF transmitter technology on non-Endangered Species Act listed shorebird and seabirds with the aim of informing future studies on two species of high conservation concern, the federally threatened Piping Plover (Charadrius melodus) and the federally endangered Roseate Tern (Sterna dougallii).Publication Integrated Urban Metabolism Analysis Tool (IUMAT)(2016-09) Mostafavi, NarimanA number of tools are available today for simulating different aspects of urban activity, but these efforts are fragmented and do not effectively reflect the interrelationships between very diverse groups of urban sectors and resource flows. There is a critical need for robust and reliable urban metabolism analysis tools that integrate socio-economic elements of urbanization and physicality of the built environment into evaluating sustainability in cities. This dissertation outlines the development of an Integrated Urban Metabolism Analysis Tool (IUMAT) that dynamically measures the environmental impacts of land cover, transportation, and consumption of energy, water and materials employing a holistic framework. It includes examination of the existing scholarship on urban metabolism as well as description of the calculative framework for IUMAT. The scope of work is establishment of the Residential Energy Model that would serve as a template for the larger Energy, Water and Materials (EWM) Model. The EWM model takes a bottom-up approach to generate spatial resource demand profiles based on building and neighborhood characteristics. Finally, Residential Energy Consumption Survey (RECS) 2009 data is used to explain how the proposed framework makes use of actual data to find determinants of resources’ demand and unravel correlations between environmental consequences and myriad of urban variables. Quantile regression is explored as a robust method for large-scale energy modeling that is a prototype for resource use projection within other urban sectors.Publication Characterizing the urban human environment system in Boston, Massachusetts(2016-05) Danford, Rachel SAccess to natural resources and restorative green space, especially in urban areas, has become critically important as an increasing number of people throughout the world move into cities. Stewardship of natural spaces and a sense of engagement with these environmental benefits are crucial, especially in urban areas where access to nature is more difficult and less equitable. This research proposes a model where individual and policy level values and decisions shape how urban nature is used, which affects the adoption of environmentally responsible behavior and natural resource conservation and in turn feeds back into environmental values and decisions. The research addresses four gaps in the existing literature; 1) the affect of risk on individual level ERB on private property, 2) how environmental attitudes affect policy level decisions about natural resource conservation, 3) how ecological availability can limit equitable distribution of urban green space, and 4) the ways in which users engage with small, community-driven urban green spaces. Policy implications and suggestions for further research are also discussed.Publication The Effectiveness and Applicability of Amphibians as Indicator Species for Long-Term Monitoring of Ecological Changes in New England Forests(2015-05) SIDDIG, AHMEDThe objective of this study is to assess the potential of two amphibians species, Eastern Red-backed Salamander (Plethodon cinereus (Green)) and Eastern Red-spotted Newt (Notopthalmus viridescens viridescens Rafinesque), as indicator species of forest disturbances at Harvard Forest, located in Petersham, Massachusetts, United States. Specifically, I 1) assess the impacts of these focal species to decline of hemlock forests in Harvard Forest; 2) calibrate abundance indices of P. cinereus based on artificial and natural objects surveys with a population size estimator based on depletion sampling; and 3) assess the potential of these salamanders as indicator species by developing an objective and multimetric method. My results showed that decline of Eastern Hemlock (Tsuga canadensis) forests due to invasive insects has increased the occupancy of P. cinereus but significantly reduced its estimated abundance and detection probability. Similarly, the estimated abundance of N. v. viridescens also declined dramatically after hemlock decline. The anticipated transition from forests dominated by T. canadensis to mixed-hardwood may alter the abundance and detection probability of both salamander species by up to 50%. Abundance indices based on both cover board and natural object surveys were able to be calibrated using density estimates of P. cinereus derived from depletion (removal) surveys. The cover-board abundance index was eight times higher than the estimated density of P. cinereus, whereas the natural object survey was half the size of the density estimator. I introduced the Indicator Species Potential (ISP) index – a multi-metric method to quantify the efficacy of indicator species in classifying sites, monitoring ecological changes, and assessing desired management conditions. When applied to salamanders as potential indicators of changes in forests in Massachusetts, the ISP suggests that P. cinereus is a reasonable indicator for ecological change in hemlock stands whereas N. viridescens is a potential IS in mixed hardwoods. Overall, the ISP shows promise as a method for summarizing ecological and statistical information about potential IS in a single value.Publication Local Governmental Collective Action and Mandated Policy Implementation(2024-02) Roberts, Michael DGroundwater depletion is a global concern. Around the world, groundwater supplies more than half the water used for agriculture and human drinking. Many other species and ecosystems are supported by groundwater and rely on the integrity of groundwater and surface water connections. Like many social and environmental problems, addressing the overextraction of groundwater requires collective action across governmental authorities and jurisdictions. To date, there are few examples of successful, voluntary groundwater management. To steer collective action at the local level, higher levels of government often use policy mandates. This dissertation examines the implementation of one such mandate. California’s Sustainable Groundwater Management Act (SGMA), a state-legislated mandate, was passed in 2014. SGMA requires local governmental agencies to work together to address decades of groundwater depletion. From 2018-2022, I conducted ethnographic fieldwork to study the mandated groundwater management planning processes that were undertaken by hundreds of local governmental agencies who, for the first time in California’s history, were faced with a choice: either they work across their jurisdictions to achieve groundwater sustainability or they forfeit their local control of groundwater resources to the state of California. Using a comparative case analysis approach, I address three core topics that are currently underexplored in research on mandated policy implementation: what motivates local governmental agencies to engage in collective action when under a mandate, how do local governmental agencies interact with one another to achieve mandate requirements, and why do we see variation in the ways local governmental agencies interpret their role in mandate implementation.Publication Coquerel's Sifaka (Propithecus coquereli): A Starring Role in the Drama of Deforestation in Northwestern Madagascar(2023-09) Suzzi-Simmons, Amanda EMadagascar, renowned for its unique biodiversity and diverse ecosystems, faces increasing threats to its wildlife, including lemurs. Lemurs are ideal ambassadors for habitat preservation and restoration in Madagascar since they are charismatic primates reliant on healthy forests to thrive. They are a highly diverse taxonomic group (>100 species) and at the same time the most threatened group of mammals with about 94% of all assessed species being categorized as either vulnerable, endangered, or critically endangered. This research aims to examine the potential impacts of climate change and human-induced factors on the distribution of Propithecus coquereli in northwestern Madagascar. Employing species distribution modeling (SDM) techniques, I analyzed a comprehensive dataset comprising various environmental variables, including geology, climate, topography, and forest cover. Our bibliometric analysis chapter complements the research by providing an in-depth examination of the existing scientific literature on the subject. Through a systematic review and quantitative analysis of peer-reviewed publications, I assess the breadth and depth of research pertaining to P. coquereli's habitat, behavior, conservation, and factors affecting its distribution. The results from the SDM underscore the critical significance of forested habitats in shaping the suitability of environments for P. coquereli. The species demonstrates a strong association with the highly fragmented western tropophilous forest, relying on these patches during its movements through the expanding savannah and xerophytic bush. Alarmingly, our projections indicate a significant decline in suitable habitat for P. coquereli, with potential extinction anticipated even before 2050. The findings from the deforestation chapter complement the species distribution modeling, revealing the detrimental effects of deforestation on the availability of suitable habitats for P. coquereli. The loss of forested areas poses a severe threat to the species, particularly in the already fragmented northwestern dry forest region. As this chapter underscores, deforestation is a significant driver of habitat loss, exacerbating the challenges faced by P. coquereli's survival and contributing to the decline in its distribution range. Together, the deforestation chapter and species distribution modeling offer a comprehensive understanding of the complex interplay between climate change, human activities, and habitat loss on P. coquereli's distribution. These combined insights provide a robust foundation for formulating conservation strategies that can effectively address the challenges posed by deforestation and contribute to the preservation of this critically endangered lemur species and the unique biodiversity of Madagascar. In light of the anticipated habitat loss, identifying potential climate change refugia for P. coquereli remains crucial. Corridors that facilitate the expansion of the species' range could aid in adapting to changing environmental conditions and maintaining larger populations. Conservation strategies must urgently address the vulnerability of this endemic species to climate change and habitat loss. A comprehensive approach involving ecological preservation, sustainable resource management, and community engagement is essential for safeguarding Madagascar's rich biodiversity. Nevertheless, as we explore the implications of our findings, it is crucial to exercise caution and not overstate the reach of our results. This research serves as a foundation for future studies and conservation efforts, focusing on the survival and protection of P. coquereli and other endangered species in Madagascar's dynamic and fragile ecosystems. In conclusion, this study combines cutting-edge species distribution modeling with a comprehensive bibliometric analysis, shedding light on the urgent need for targeted conservation strategies. With Madagascar's ecosystems far from equilibrium and the loss of biodiversity already evident, concerted efforts from the global scientific community, policymakers, and local stakeholders are indispensable to protect the invaluable natural heritage of the island.Publication Mineral and Metabolic Constraints on Carbon Cycling Within and Export From Mountainous Floodplain Soils(2023-09) Anderson, CamFloodplains contain soils rich in organic matter and are important ecosystems for agricultural production worldwide. Importantly, seasonal flooding results in drastic redox fluctuations, which have profound implications for transformations of soil carbon (C). However, we do not know the underlying biogeochemical controls on and spatiotemporal variation of soil C cycling in redox-dynamic floodplains. Using an active meander of the subalpine East River watershed (Gothic, CO), this dissertation first reviews the current understanding of floodplain C import, storage, and export, and further discusses how hydrology and corresponding redox patterns impact mineral and metabolic controls of floodplain C transformations. Using a combination of sequential extractions, physical fractionation, and high-resolution mass spectrometry, Chapter 2 finds that mineral-associated C constitutes a meaningful fraction of total C, suggesting that mineral-organic associations are quantitatively important for floodplain soil C protection. Chapter 3 investigates mechanisms of anaerobic protection that drive floodplain C cycling. Studying the same meander, metabolite data show evidence for kinetic constraints during flooding, leading to an accumulation of relatively higher molecular weight compounds. Upon drainage, thermodynamic constraints are relieved in the surface soils, but deep soils remain reducing year-round. Chapter 4 aims to resolve the balance between mineral and metabolic constraints on floodplain C loss, across extreme low (2018) and high (2019) river discharge years. Using similar techniques as above, in combination with environmental monitoring, we found that reducing conditions (1) decreased the stability of iron-carbon associations, causing concomitant mobilization of iron and DOC, and (2) resulted in the selective preservation of reduced DOC compounds; both findings were stronger during extreme flooding. Connecting these mechanisms to riverine exports of floodplain C showed shifts in the balance of inorganic versus organic C export during extreme drought or flooding. Climate change is shifting the extent of flooding in mountainous floodplains, with prolonged megadrought expected to drive more low water years. Thus, understanding the mechanisms that control floodplain C cycling will be crucial to maintaining healthy floodplains that can sustain food productivity and clean water.