Environmental Chemistry Commons^™

Representing Methane Emissions From Wet Tropical Forest Soils Using Microbial Functional Groups Constrained By Soil Diffusivity, Debjani Sihi, Xiaofeng Xu, Mónica Salazar Ortiz, Christine S. O'Connell, Whendee L. Silver, Carla López-Lloreda, Julia M. Brenner, Ryan K. Quinn, Jana R. Phillips, Brent D. Newman, Melanie A. Mayes

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Tropical ecosystems contribute significantly to global emissions of methane (CH₄), and landscape topography influences the rate of CH₄ emissions from wet tropical forest soils. However, extreme events such as drought can alter normal topographic patterns of emissions. Here we explain the dynamics of CH₄ emissions during normal and drought conditions across a catena in the Luquillo Experimental Forest, Puerto Rico. Valley soils served as the major source of CH₄ emissions in a normal precipitation year (2016), but drought recovery in 2015 resulted in dramatic pulses in CH₄ emissions from all topographic positions. Geochemical parameters …

Soil Quality Indices As Affected By Long-Term Burning, Irrigation, Tillage, And Fertility Management, Helen C.S. Amorim, Amanda Ashworth, Kristofor R. Brye, Brian J. Wienhold, Mary C. Savin, Phillip R. Owens, Sergio Silva

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Understanding the impacts of long-term agricultural practices on soil quality (SQ) is key for sustaining agroecosystem productivity. This study investigated conventional and no-tillage (NT), residue burning and no burning, residue level (high and low), and irrigation (irrigated and dryland) effects on soil properties, SQ, and crop yields following 16 yr of a wheat (Triticum aestivum L.)–soybean [Glycine max (L.) Merr.] double-crop system via the Soil Management Assessment Framework (SMAF). A field experiment was conducted in the Lower Mississippi River Delta region on a silt-loam soil. Bulk density, soil organic C (SOC), total N (TN), pH, electrical conductivity (EC), …

Characterization Of Microbial Populations In Landfill Leachate, Umut M. Bicim, Hanna Fulford, Lori A. Hoagland, Alejandro R. Sanchez, Amisha D. Shah, Inez Hua

Discovery Undergraduate Interdisciplinary Research Internship

In the United States, municipal solid waste (MSW) landfills remain a potential mining source of recoverable materials, including but not limited to critical, precious, and rare earth metals found in electronic waste. This is possible due to collectible leachate that filters through MSW landfills, carrying metals, nutrients of value, and microbes—some of which may hold key metal bioleaching properties—within. The purpose of this study is to begin analyzing leachate from MSW landfills in the American Midwest to understand the composition of microbial communities within these landfills. Landfill leachate samples sourced in northern Indiana, representing the landfill process during unique times …

The Quantitative Assessment Of Pond Scum: An Examination Of The Biogeochemistry Of Phosphorus Cycling In The Belgrade Lakes, Abbey M. Sykes

Honors Theses

The internal recycling phosphorus in freshwater lake bottom sediments represents a significant source of hypolimnetic phosphorus (P) release for many of Maine’s lakes. In summer months, Maine lakes often thermally stratify and the lake hypolimnion develops anoxia, leading to a reduction in redox potential at the sediment-water interface. These reducing conditions facilitate the reductive dissolution of ferric iron, and, since phosphorus is often present in freshwater lake sediments as solid FeOOH-PO₄ complexes, results in release of soluble phosphorus into the water column. Our current study presents field and laboratory data from sediment fractionation extractions designed to quantify concentrations of …

Bow Lake (Station 3 - Bennett) 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Bow Lake, Station 3 Bennett (Barrington and Northwood, NH) for 2021.

Lovell Lake 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Lovell Lake (Sanbornville, NH) for sampling efforts in 2021.

Biolability Of Fresh And Photodegraded Pyrogenic Dissolved Organic Matter From Laboratory-Prepared Chars, K. W. Bostick, A. R. Zimmerman, A. I. Goranov, S. Mitra, P. G. Hatcher, A. S. Wozniak

Chemistry & Biochemistry Faculty Publications

Pyrogenic dissolved organic matter (pyDOM) is known to be an important biogeochemical constituent of aquatic ecosystems and the carbon cycle. While recent studies have examined how pyDOM production, composition, and photolability varies with parent pyrogenic solid material type, we lack an understanding of potential microbial mineralization and transformation of pyDOM in the biogeosphere. Thus, leachates of oak, charred at 400 °C and 650 °C, as well as their photodegraded counterparts were incubated with a soil‐extracted microbial consortium over 96 days. During the incubation, significantly more carbon was biomineralized from the lower versus higher temperature char leachate (45% vs. 37% lost, …

Baboosic Lake 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Baboosic Lake (Amherst and Merrimack, NH) for 2021.

Province Lake 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Province Lake (Wakefield, NH and Parsonsfield, ME) for 2021.

Belleau Lake 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Belleau Lake in Wakefield, NH for 2021.

Balch Pond 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Balch Pond (Wakefield, NH; Acton and Newfield, ME) for sampling efforts up to 2021.

Valorization Of Xylan In Agroforestry Waste Streams, Harrison Appiah

Graduate Theses, Dissertations, and Problem Reports (ETD)

Valorization of Xylan in Agroforestry Waste Streams.

Harrison Appiah

Microwave-assisted deep eutectic solvent and gamma-valerolactone metallic chloride catalyzed conversion of xylan to furfural were investigated using a 2x3 factorial experimental design at two levels of percent microwave power, reaction time, and catalyst concentration. The levels of each factor studied were (20%, 60% microwave power, 2, 4 minutes, and 10, 20mg) respectively. The effect of three metallic chloride catalysts (LiCl, FeCl3.6H20, CuCl2) on the conversion of xylan to furfural was also investigated. The gamma-valerolactone-ferric chloride sent system exhibited the highest mean yield of furfural (56.50%). The next highest furfural yield of …

Bow Lake (Station 1 - Ledges) 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Bow Lake, Station 1 Ledges (Barrington and Northwood, NH) for 2021.

Lake Ivanhoe 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

A Water Quality Highlight Report by UNH CE Lakes Lay Monitoring Program for Lake Ivanhoe (Wakefield, NH) for sampling efforts in 2021.

Pine River Pond 2021 Water Quality Highlight Report, Amanda Mcquaid, Robert Craycraft

UNH Cooperative Extension

No abstract provided.

Online Ultra-High Performance Liquid Chromatography-Charge Transfer Dissociation-Mass Spectrometry (Uhplc-Ctd-Ms) Of Complex Mixtures Of Oligosaccharides, Praneeth M. Mendis

Graduate Theses, Dissertations, and Problem Reports (ETD)

Abstract

Online Ultra-High Performance Liquid Chromatography-Charge Transfer Dissociation-Mass Spectrometry (UHPLC-CTD-MS) of Complex Mixtures of Oligosaccharides

Praneeth M. Mendis

Complex carbohydrates make up more than half the biomass on earth, and they are crucial to a wide range of processes in living organisms. When polysaccharides and glycans are enzymatically digested into manageable units called oligosaccharides, they typically consist of 2-20 linear or branched sugar units. The detailed structural analysis of oligosaccharides assists in the identification of structural and chemical properties of the polymers from which they derive. Tandem mass spectrometry (MS/MS) is a key technique used in oligosaccharides structural characterization. Within …

Corn And Soybean Response To Wastewater-Recycled Phosphorus Fertilizers, Shane Ylagan

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

The ability to recycle phosphorus (P) from wastewaters could provide a sustainable, continuous source of P that might also help protect surface water quality from P enrichment. The mineral struvite (MgNH4PO4·6H2O) is an understudied material that can be created from Pcontaining wastewater and has been shown to have agricultural fertilizer value. The objective of this study was to evaluate the effects of electrochemically precipitated struvite (ECST), chemically precipitated struvite (Crystal Green; CG), diammonium phosphate (DAP), monoammonium phosphate (MAP), rock phosphate (RP), and triple super phosphate (TSP) on corn (Zea mays) and soybean (Glycine max) response in a 79-day greenhouse pot …

Eelgrass (Zostera Marina) Population Decline In Morro Bay, Ca: A Meta-Analysis Of Herbicide Application In San Luis Obispo County And Morro Bay Watershed, Tyler King Sinnott

Master's Theses

The endemic eelgrass (Zostera marina) community of Morro Bay Estuary, located on the central coast of California, has experienced an estimated decline of 95% in occupied area (reduction of 344 acres to 20 acres) from 2008 to 2017 for reasons that are not yet definitively clear. One possible driver of degradation that has yet to be investigated is the role of herbicides from agricultural fields in the watershed that feeds into the estuary. Thus, the primary research goal of this project was to better understand temporal and spatial trends of herbicide use within the context of San Luis …

Population Genetics Of Rhizophora Apiculata In Peninsular Malaysia Using Microsatellite Markers, Amelia Azman

Student Works (2020-2029)

Rampant illegal logging, overharvesting and deforestation coupled with climate change, pose significant threats to the natural stands of Rhizophora apiculata, or locally known as Bakau Minyak; one of the most economically and ecologically important species of mangroves in Peninsular Malaysia. Despite being a dominant mangrove species, the reduction in the number of R. apiculata in its habitat has resulted in concerns over the long-term survival potential of the species. In Malaysia, genetic information to develop effective guidelines for the conservation and management of mangrove species has been lacking, and hence, further research should be conducted to fill this gap. The …

Algal Biomarkers As A Proxy For Pco2: Constraints From Late Quaternary Sapropels In The Eastern Mediterranean, Caitlyn R. Witkowski, Marcel T.J. Van Der Meer, Brian Blais, Jaap S. Sinninghe Damsté, Stefan Schouten

Science and Technology Department Faculty Journal Articles

Records of carbon dioxide concentrations (partial pressure expressed as pCO2) over Earth’s history provide trends that are critical to understand our changing world. To better constrain pCO2 estimations, here we test organic pCO2 proxies against the direct measurements of pCO2 recorded in ice cores. Based on the concept of stable carbon isotopic fractionation due to photosynthetic CO2 fixation (Ɛp), we use the stable carbon isotopic composition (δ13C) of the recently proposed biomarker phytol (from all photoautotrophs), as well as the conventionally used alkenone biomarkers (from specific species) for comparison, to reconstruct pCO2 over several Quaternary …

Testing Flowering Perennial Plants In A Bermudagrass (Cynodon Spp.) Lawn, Paige Elizabeth Boyle, Michelle Wisdom

Horticulture Faculty Publications and Presentations

Most pollinating insects require a season-long succession of floral resources to fulfill life-cycle requirements. Incorporating forbs into turfgrass sites may create a season-long sequence of flowers to support foraging pollinators. However, persistence of forbs in warm-season turfgrasses such as bermudagrass (Cynodon spp.) may be affected by the competitive nature of the turfgrass and routine management practices such as mowing. A 2-year study was conducted to evaluate seven forbs (Bellis perennis L., Lotus corniculatus L., Prunella vulgaris L., Trifolium fragiferum L. ‘Fresa’, Trifolium repens L. ‘Durana’ and ‘Resolute’, Trifolium subterraneum L.) for persistence and ability to produce floral resources …

Optimisation Of Biomass And Lipid Production Of A Tropical Thraustochytrid Aurantiochytrium Sp. Umacc-T023 In Submerged-Liquid Fermentation For Large-Scale Biodiesel Production, Sohedein Mohamad Nor Azzimi

Student Works (2020-2029)

A tropical thraustochytrid, Aurantiochytrium sp. UMACC-T023, was optimised for high biomass and lipid production in submerged-liquid fermentation (SLF). Biomass and lipid production were optimised based on glucose, polypeptone, and yeast extract concentration using response surface methodology (RSM). In RSM, the applied central composite design (CCD) showed that the optimisation model was significant for all variables studied. Yeast extract and polypeptone were associated with significant effects in UMACC-T023 biomass production with p < 0.05. The model was validated by employing the optimised media composition in shake flasks and in 1.4-L stirred-tank bioreactors. The optimised media composition for both biomass and lipid production was 10 g L-1 glucose, 15.08 g L-1 polypeptone, and 13.56 g L-1 yeast extract. Biomass production in the bioreactor increased 2.12-fold compared with the shake flask culture utilising the same optimised media composition. This result demonstrated that the optimized media composition can be utilised for large-scale lipid production of UMACC-T023 for potential biodiesel feedstock as it also fulfilled the international standards for biodiesel.

Leaf Traits Can Be Used To Predict Rates Of Litter Decomposition, Marc Rosenfield, Jennifer L. Funk, Jason K. Keller, Catrina Clausen, Kimberlee Cyphers

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Strong relationships exist between litter chemistry traits and rates of litter decomposition. However, leaf traits are more commonly found in online trait databases than litter traits and fewer studies have examined how well leaf traits predict litter decomposition rates. Furthermore, while bulk leaf nitrogen (N) content is known to regulate litter decomposition, few studies have explored the importance of N biochemistry fractions, such as protein and amino acid concentration. Here, we decomposed green leaves and naturally senesced leaf litter of nine species representing a wide range of leaf functional traits. We evaluated the ability of traits associated with leaf and …

In Situ Plant Uptake Of Excess Nutrients And Consequential Alteration Of Rhizosphere Dynamics, Srusti Maddala

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

The use of phytoremediation in ecological remediation projects has numerous benefits including soil stabilization and nutrient uptake. Recently, microdialysis, a diffusion-based sampling technique commonly used in biomedical research, has been recognized as a candidate for monitoring chemical changes in the rhizosphere. The real-time, in situ data it provides about nutrient diffusion may improve the management and success of restoration projects. Therefore, the objective of this study was to employ the technique of microdialysis in the novel application of quantifying the diffusive flux of inorganic nitrogen compounds in the rhizosphere of native plants of Arkansas. The microdialysis technique was first optimized …

Toxicity Analysis Of 2’-Deoxyguanosine-N2-6-Aminopyrene And 2’-Deoxyguanosine-N2-8-Aminopyrene In Escherichia Coli, Emily Janeiro

Honors Scholar Theses

Cancer is a disease that stems from genomic errors that are not corrected properly by cellular repair mechanisms. Errors are more likely to form when organisms are subjected to DNA damage by mutagenic compounds. 1-Nitropyrene, a nitrated polycyclic aromatic hydrocarbon (nitro-PAH), has been shown to be a potent mutagen that causes cancer. Nitro-PAHs can arise from diesel exhaust products in the environment. Out of all nitro-PAHs, 1-nitropyrene is found in largest quantities in the environment. This poses a great need to study its effects biochemically in order to address its toxicity in DNA. Other nitropyrene derivatives, including 1,6-dinitropyrene and 1,8-dinitropyrene, …

Spectroscopic And Computational Studies Of The Agricultural Active Ingredient Dicamba, James Johnson

Honors Theses

3,6-dichloro-2-methoxy benzoic acid, more commonly known as Dicamba, is the active ingredient in an array of pesticides used on farmlands across the globe. Dicamba’s mode of action works by mimicking the plant hormone auxin, which is synonymous to growth hormones in mammals. The mimicking of auxin results in excessive elongation and growing, which is eventually fatal for plants when the rate of growth can no longer be sustained. Dicamba has risen in prominence in recent years due to drift damage as a result of Dicamba’s high volatility. Having the ability to identify Dicamba is crucial for the agricultural industry. The …

385— Optimizing Nitrogen Concentrations To Maximize Lipid Yields For Biodiesel Production, Wady Jacoby, Daria Zhogina, Pavel Ananev, Lauren Saggese, Max Muller, Barnabas Gikonyo

GREAT Day Posters

Select subspecies of microalgae are considered to be the most promising candidates for third generation renewable resources of biodiesel. Algae not only ingest excess carbon emissions from the atmosphere, they also convert it into energy-dense lipids which can be harvested, and then transformed into biodiesel. However, before the fuel industry can adopt algae farming as a realistic alternative to fossil fuels, the process of harvesting algal lipids must be optimized further. Our research aims to make algal lipid extraction more realistic by determining the ideal growing conditions of the algae species Chlorella Vulgaris. Our research this semester focused on two …

Senior Project: An Investigative Study Into The Bacterial Contamination Of Little Black Creek, Margaret I. Brenneman

Honors Projects

An investigation of Escherichia coli concentrations in a west Michigan stream was conducted to determine sources of fecal contamination that impact water quality. Little Black Creek (LBC) is located in Muskegon County and discharges into Lake Michigan at the P.J. Hoffmaster Campground Beach. Often referred to as an “indicator bacteria,” water contaminated with E. coli has a high probability to contain other enteric pathogens as well. Beach water testing in 2020 using Colilert-18 methods revealed E. coli levels of 579 cfu/100mL in the creek discharge area that exceeded total body contact criteria of 300 cfu/100mL. A follow-up study of the …

Assessment Of Soil Protein And Refractory Soil Organic Matter Across Two Chronosequences Of Newly Developing Marshes In Coastal Louisiana, Usa, Stuart Alexander Mcclellan

LSU Doctoral Dissertations

The impacts of sea-level rise and hydrologic manipulation are threatening the stability of coastal marshes throughout the world, thereby increasing the potential for re-mineralization of soil organic matter (SOM) in these systems. Such threats have prompted marsh restoration efforts, particularly in coastal Louisiana, yet it is unclear how the slowly decomposing (refractory) and quickly decomposing (labile) fractions of SOM may be differentially affected by different approaches to marsh restoration. Additionally, otherwise labile compounds may accumulate in the soil via a range of protective mechanisms, including rapid burial and association with organic compounds that are thought to enhance soil aggregation, such …

Analysis Of Organochlorine Pesticides Levels In Irrigation Water From Various Water Sources Across Egypt, Omar Tarek Khairy

Theses and Dissertations

Organochlorine pesticides are extensively used in agriculture to cope with the world’s increasing population and demands for nutrition. This class of pesticides poses a serious risk to human health upon chronic exposure to elevated levels. Determination of organochlorine pesticides levels in water has been extensively covered in literature in Egypt and other parts of the world. The need for up-to date data and statistical information regarding the levels of organochlorine pesticides in water is ever increasing. These compounds, although a lot have been prohibited from use decades ago, can still be detected in trace levels in water due to their …