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2021

Soil

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Articles 1 - 29 of 29

Full-Text Articles in Life Sciences

Long Term Observation Of The Grassland Vegetation Used Intensively Or Extensively And Ecologically, H.-D. Matthes, J. Matthes, W. Jentsch, V. Pastushenko Dec 2021

Long Term Observation Of The Grassland Vegetation Used Intensively Or Extensively And Ecologically, H.-D. Matthes, J. Matthes, W. Jentsch, V. Pastushenko

IGC Proceedings (1997-2023)

The aim of the present paper was to study alterations of the grassland flora from 55 plots following a more extensive management under long term observation within 6 years. Extensification of grassland use leads to an increase of the numbers of plant species by 32%, “Red-list-species” included. The moisture number of the soils slightly increased and the reaction and nitrogen numbers decreased. Results are presented for different vegetation units.


Mercury Contamination In Selected Edible Plants And Soil From Artisanal And Small-Scale Gold Mining In Sukabumi Regency, Indonesia, Grace Serepina Saragih, Ely Rahmi Tapriziah, Yunesfi Syofyan, Siti Masitoh, Yohana Sari Hotmatua Pandiangan, Andriantoro Andriantoro Dec 2021

Mercury Contamination In Selected Edible Plants And Soil From Artisanal And Small-Scale Gold Mining In Sukabumi Regency, Indonesia, Grace Serepina Saragih, Ely Rahmi Tapriziah, Yunesfi Syofyan, Siti Masitoh, Yohana Sari Hotmatua Pandiangan, Andriantoro Andriantoro

Makara Journal of Science

Artisanal and small-scale gold mining (ASGM) activities often pollute soil, water, and air, thereby achieving widespread proliferation, and contaminating the surrounding biota including plants. Mercury contamination on agricultural land around ASGM areas has been widely reported. This study aims to determine the total mercury contamination in plants and soil around active ASGM sites in Sukabumi Regency, Indonesia, namely, Waluran, Lengkong, and Ciemas Districts. Total mercury (Hg) content was measured from 27 plant samples (including cassava [Manihot utilisima], rice [Oryza sativa], and papaya [Carica papaya]), 7 rhizosphere soil samples, and 7 non-rhizosphere soil samples. Data …


A Method For Visualizing Water Flow Through Modified Root Zones, Dallas M. Williams Dec 2021

A Method For Visualizing Water Flow Through Modified Root Zones, Dallas M. Williams

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

As the number of impervious surfaces in urban environments increases, the ability of modified root zones to infiltrate water is becoming more important. Current methods of tracing water flow through soil profiles include excavating large pits in situ or analyzing soil cores in the laboratory with computed tomography or magnetic resonance imaging. While useful, these methods may not be suitable for urban settings or practical in every laboratory. We propose a new method that is less invasive, does not require extensive technical equipment and can reliably trace water movement through the soil profile in order to calculate flow rate based …


Cover Crop Effects On Near-Surface Soil Aggregate Stability In The Southern Mississippi Valley Loess (Mlra 134), Chandler M. Arel Dec 2021

Cover Crop Effects On Near-Surface Soil Aggregate Stability In The Southern Mississippi Valley Loess (Mlra 134), Chandler M. Arel

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Intensive agricultural cultivation within major land resource area (MLRA) 134, the Southern Mississippi Valley Loess, has led to soil erosion, soil compaction, and the overall destabilization of near-surface soil aggregates. The use of cover crops during the agricultural offseason has been shown to help alleviate soil compaction and provide stabilizing effects against soil erosion, which are particularly important as the silty soils of MLRA 134 have a large erosion potential. This study evaluated the effects of cover crop and no-cover crop treatment on silt-loam soils within MLRA 134. Treatments were implemented during Fall 2018 and Fall 2019 and consisted of …


Hydrologic Controls On Phosphorus Speciation And Mobilization In A Subalpine Watershed (East River, Colorado), Lucia Isobel Arthen-Long Oct 2021

Hydrologic Controls On Phosphorus Speciation And Mobilization In A Subalpine Watershed (East River, Colorado), Lucia Isobel Arthen-Long

Masters Theses

The cycling of phosphorus (P) through floodplain environments is critical to ecosystem productivity and has significant implications on both water quality and soil fertility. P export from soils in response to saturation has been well documented, but the relative vulnerability of specific P pools to mobilization remains poorly constrained, as do the mechanisms mediating its release. The prediction of P availability in and export from mountainous floodplain soils is of great importance as global climate change is projected to significantly alter precipitation regimes in alpine systems. This study combined a thorough characterization of P distribution across a hillslope to floodplain …


Plant Root Mass Fraction Response To Soil Resource Limitation In The Context Of Dry Mediterranean Rangeland, Guy Dovrat Oct 2021

Plant Root Mass Fraction Response To Soil Resource Limitation In The Context Of Dry Mediterranean Rangeland, Guy Dovrat

IGC Proceedings (1997-2023)

Root mass fraction (RMF) was proposed as a stable measurement of plant resource partitioning that can represent plant acquisition–conservation trade‐offs. We examined the effects of soil resources availability on RMF of abundant annual plant species of water-limited rangeland. We used data from controlled experiments in which nine species were grown under variable water and nitrogen availabilities and their root and shoot biomass were examined at flowering time. In legumes we examined also presence of N2-fixation. In all of the species, reduced water and/or nitrogen availability was associated with increased RMF. However, the magnitude of variation in RMF found …


Response Of The Soil Bacterial Community, Resistome, And Mobilome To A Decade Of Macrolide Antibiotic Contamination, Liam Paul Brown Sep 2021

Response Of The Soil Bacterial Community, Resistome, And Mobilome To A Decade Of Macrolide Antibiotic Contamination, Liam Paul Brown

Electronic Thesis and Dissertation Repository

Biosolids (treated sewage sludge) are used as agricultural fertilizer but are frequently contaminated with macrolide antibiotics, to which resistance is rising among historically susceptible bacteria. To determine if the land-application of macrolides carried in biosolids could promote antibiotic resistance in soil bacteria, soil plots were exposed annually to environmentally realistic or high doses of macrolides for ten years. I sequenced the bacterial 16S ribosomal DNA, metagenomic DNA, and integron gene cassettes within the treated and antibiotic-free soil to compare the compositions and diversities of the bacterial communities, antibiotic resistance genes, and mobile genetic elements. I determined that the high dose …


Soil Carbon And Nitrogen Dynamics After Pasture Installation In The Amazon Region, C. C. Cerri, M. Bernoux, C. E. P. Cerri Sep 2021

Soil Carbon And Nitrogen Dynamics After Pasture Installation In The Amazon Region, C. C. Cerri, M. Bernoux, C. E. P. Cerri

IGC Proceedings (1997-2023)

The objective of this paper is to present the soil carbon (C) and nitrogen (N) dynamics in a chronosequence made of a forest and pastures of different ages established in a Oxisol in the Western Brazilian Amazon Basin. The results of soil Carbon and Nitrogen stocks and gases fluxes were discussed. Stable 13C isotopic technique was used to calculate for a determinate age of pasture installation, the proportion of soil C remaining from the forest system and the proportion of soil C introduced by the grasses of the pasture system. The C lost from the original pool under the …


Nutrient Dynamics And Inventory In Tropical Grassland Ecosystem In Southern India, K. Karunaichamy, Kailash Paliwal Sep 2021

Nutrient Dynamics And Inventory In Tropical Grassland Ecosystem In Southern India, K. Karunaichamy, Kailash Paliwal

IGC Proceedings (1997-2023)

The present study was to ascertain the distribution of calcium (Ca), magnesium (Mg) and sodium (Na) in the different plant components and in the soil top 30 cm at Kalikesam in Western Ghats region of southern India. Magnesium concentration increased in the order: dead shoots > belowground > litter > aboveground live. Sodium concentration in live shoots was maximum in February (0.51%) and minimum in August (0.05%). Annually 8.94 g/m2 Ca, 2.41g/ m2 Mg and 2.30g/ m2 Na was taken up by plants. The distribution of the three nutrients in plant/soil system indicated that the major portion of the nutrients …


Nitrogen Budgets On A Pasture Under Combined Utilization Of Grazing And Cutting, Y. Kurokawa, S. Yamamoto, Y. Iijima, M. Kitagawa, F. Omata, S. Sakamoto, H. Tanaka, S. Suzuki, T. Shioya Sep 2021

Nitrogen Budgets On A Pasture Under Combined Utilization Of Grazing And Cutting, Y. Kurokawa, S. Yamamoto, Y. Iijima, M. Kitagawa, F. Omata, S. Sakamoto, H. Tanaka, S. Suzuki, T. Shioya

IGC Proceedings (1997-2023)

Nitrogen budgets on a pasture being utilized for both grazing and cutting were investigated. A pasture containing tallfescue, orchard grass and white clover was divided into two areas: initially grazed (IA, 0.41ha) and grazed after cutting for hay (BA, 0.49ha). A herd of 4-5 cattle (heifers or steers of Japanese Black or Holstein) grazed at IA from 22 Apr. to 2 Jul. and grazed at both IA and BA from 3 Jul. to 21 Oct. 1999. The amount of N grazed from IA was 3 times higher than the sum of N of grazed herbage and harvested hay from BA. …


Optimization Of Dna Extraction From Difficult Sandy-Loam Soils, Anka Colo Aug 2021

Optimization Of Dna Extraction From Difficult Sandy-Loam Soils, Anka Colo

Undergraduate Student Research Internships Conference

Ginseng is a high value perennial crop grown for its roots. A four-year cultivation cycle is required to obtain marketable ginseng roots, during which a condition called ginseng replant disease (GRD) develops. GRD is characterized by a severe root rot disease, and prevents the growth of newly planted ginseng in a former ginseng garden1. Microbiome analysis of ginseng garden soil will help our understanding of the formation of GRD and its severity. However, extracting DNA from the sandy-loam soils required for ginseng cultivation is difficult. Commercial kits are either too expensive or not applicable to the large volumes of soil …


The Analysis Of Ginsenosides In Ginseng Garden Soil, Karina Marie Kaberi Jul 2021

The Analysis Of Ginsenosides In Ginseng Garden Soil, Karina Marie Kaberi

Electronic Thesis and Dissertation Repository

American ginseng (Panax quinquefolius L.) produces natural products called ginsenosides. The biggest challenge Ontario commercial ginseng farmers face is ginseng replant disease. To understand the function of ginseng root exudates, ginsenoside accumulation and persistence over time were investigated. Currently, no reliable ginsenoside specific extraction method, characterizing the changes in soil chemistry exists. Ginsenoside extraction protocol optimization was required to determine how ginsenoside composition changed over time. Overall, protocol optimization resulted in a 30% increase in yield of ginsenosides compared to previous extraction protocols. In the ginseng gardens, ginsenoside accumulation occurs slowly and did not reach significantly measurable amounts until the …


Decomposition Of Microbial Necromass Is Divergent At The Individual Taxonomic Level In Soil, Weiling Dong, Alin Song, Huaqun Yin, Xueduan Liu, Jianwei Li, Fenliang Fan Jul 2021

Decomposition Of Microbial Necromass Is Divergent At The Individual Taxonomic Level In Soil, Weiling Dong, Alin Song, Huaqun Yin, Xueduan Liu, Jianwei Li, Fenliang Fan

Agricultural and Environmental Sciences Faculty Research

The turnover of microbial biomass plays an important part in providing a significant source of carbon (C) to soil organic C. However, whether the decomposition of microbial necromass (non-living microbial biomass) in the soil varies at the individual taxa level remains largely unknown. To fill up these gaps, we compared the necromass decomposition of bacterial and archaeal taxa by separating live microbial biomass with 18O-stable isotope probing from dead microbial biomass in soil. Our results showed that most of the microbial necromass at the operational taxonomic unit level (88.51%), which mainly belong to Acidobacteria, Actinobacteria, Gemmatimonadetes, and Proteobacteria, decomposed significantly …


Physical And Chemical Properties Of Soil, Water And Air Around Ukawu Pb-Zn Mine, Southeastern Nigeria, Nwachukwu Arthur Nwachukwu, Sikakwe Gregory Udie, Eluwa Ndidiamaka Nchedo, Uwa Clementina Ukamaka, Oluwatoyin Oluwatosin Olaosebikan Jun 2021

Physical And Chemical Properties Of Soil, Water And Air Around Ukawu Pb-Zn Mine, Southeastern Nigeria, Nwachukwu Arthur Nwachukwu, Sikakwe Gregory Udie, Eluwa Ndidiamaka Nchedo, Uwa Clementina Ukamaka, Oluwatoyin Oluwatosin Olaosebikan

Makara Journal of Science

In this study, analysis of water, and soil samples, air quality, and noise levels in Ukawu Pb-Zn mine were examined. The pH of the water samples, at 6.7, exceeded permissible levels for potable water established by the National Environmental Standard Regulatory Agency (NESREA), European Union, and World Health Organization (i.e., 7.0-8.5). The soil pH was 5.2, which indicates acidity due to acid mine drainage. Low soil pH is evidence of acid mine drainage. All cations detected in water and soil were below standard limits considered harmful by the NESREA. Measurements of precursor gases, such as O3, NO2 …


Effects Of Traditional And Microbially-Focused Restoration Techniques On Soil Communities In Tallgrass Prairies, Zachary J. Whitacre Jun 2021

Effects Of Traditional And Microbially-Focused Restoration Techniques On Soil Communities In Tallgrass Prairies, Zachary J. Whitacre

Masters Theses

Tallgrass prairies have virtually disappeared in many parts of their former range due to the conversion of this ecosystem to farmland. In more recent years there have been efforts to restore these prairies on reclaimed agricultural land. However, these restored prairies do not resemble their remnant counterparts in many ways, such as in soil microbial community composition and metrics related to carbon storage. In Chapter 1, I show that bacterial communities in a restored prairie and an adjacent remnant prairie in southwest Michigan differ in their immediate and longer-term responses to prescribed fire, a commonly used prairie restoration and maintenance …


Soil Macroinvertebrates Responses To Wildfires In The Blue Ridge Mountains, Usa, Madeline Olliff May 2021

Soil Macroinvertebrates Responses To Wildfires In The Blue Ridge Mountains, Usa, Madeline Olliff

Biology Theses

Fire has been a prevalent disturbance on Earth for millions of years. Around the globe there are several regions that have become fire adapted, including the Southeastern United States. There have been few studies examining the effects of wildland fires on soil macroinvertebrates in the Blue Ridge Mountains, in spite of the importance of these animals to soil processes and their contributions to the biodiversity of these ecosystems. During the fall of 2016, the Southeastern USA experienced numerous, large wildfires. These fires offered an opportunity to study the effects of wildland fire on soil macroinvertebrates. We sampled sites from three …


Effects Of Am Fungi From Conventional And No-Till Michigan Crop Fields On Plant And Soil Health, Derek Bennett May 2021

Effects Of Am Fungi From Conventional And No-Till Michigan Crop Fields On Plant And Soil Health, Derek Bennett

Masters Theses

Centuries of conventional till (CT) management in agriculture has depleted soil organic matter (SOM) by over 50%. While only comprising 5% in most soils, SOM provides soil with fertility and productivity. To compensate for SOM depletion, producers have been forced to increase their reliance on fertilizer and irrigation to maintain yields. In the coming decades, climate change is expected to challenge food production and threaten an already fragile system. With no remaining land left to cultivate, conservation management strategies such as no-till (NT) look to restore SOM and increase the resilience of food production for an ever growing, increasingly food …


Does Integrating Crops With Livestock Production Impact Soil Properties And Crop Production?, Lindsey Anderson May 2021

Does Integrating Crops With Livestock Production Impact Soil Properties And Crop Production?, Lindsey Anderson

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Re-integrating crop and livestock production through cover crop (CC) and corn residue grazing could efficiently utilize resources and ensure profitability while improving environmental quality, but how this integration affects soils and crops is not well understood. We conducted two studies to address this. In the first study, we evaluated the impact of cattle (1.3-3.7 head ha-1) grazing an oat (Avena sativa L.) CC on soil and crop yields in two adjacent irrigated no-till corn (Zea mays L.)-soybean (Glycine max L.) fields on silt loam soils in eastern Nebraska. Field I was grazed twice, while Field …


Distribution, Diversity, And Biogeography Of Anaerobic Carbon Monoxide Uptake By Microbial Communities In Soils And Sediments, Amber N. Depoy Mar 2021

Distribution, Diversity, And Biogeography Of Anaerobic Carbon Monoxide Uptake By Microbial Communities In Soils And Sediments, Amber N. Depoy

LSU Master's Theses

Carbon monoxide (CO) is primarily known for being a toxic gas. However, CO is used by microorganisms as an electron or carbon source in a variety of respiratory processes. Different kinds of microorganisms utilize CO aerobically and anaerobically, using two distinct CO dehydrogenases (CODHs). Aerobes oxidize CO using a molybdenum-dependent dehydrogenase (Mo-CODH), while anaerobes utilize a nickel-dependent CO dehydrogenase (Ni-CODH). Studies of the biochemistry and microbiology of aerobic and anaerobic CO oxidation are extensive, but relatively little is known about the ecology of anaerobic CO oxidation. In an effort to test new hypotheses about the ecology of anaerobic CO oxidation, …


Wayne E. Sabbe Arkansas Soil Fertility Studies 2020, Nathan A. Slaton Mar 2021

Wayne E. Sabbe Arkansas Soil Fertility Studies 2020, Nathan A. Slaton

Arkansas Agricultural Experiment Station Research Series

Rapid technological changes in crop management and production require that the research efforts be presented in an expeditious manner. The contributions of soil fertility and fertilizers are major production factors in all Arkansas crops. The studies described within will allow producers to compare their practices with the university’s research efforts. Additionally, soil-test data and fertilizer sales are presented to allow comparisons among years, crops, and other areas within Arkansas.


Contamination Assessment Of Heavy Metals In Agricultural Soil, In The Liwa Area (Uae), Ahmed A. Al-Taani, Yousef Nazzal, Fares M. Howari, Jibran Iqbal, Nadine Bou Orm, Cijo Madathil Xavier, Alina Bărbulescu, Manish Sharma, Cristian Stefan Dumitriu Mar 2021

Contamination Assessment Of Heavy Metals In Agricultural Soil, In The Liwa Area (Uae), Ahmed A. Al-Taani, Yousef Nazzal, Fares M. Howari, Jibran Iqbal, Nadine Bou Orm, Cijo Madathil Xavier, Alina Bărbulescu, Manish Sharma, Cristian Stefan Dumitriu

All Works

The Liwa area is a primary food production area in the United Arab Emirates (UAE) and has intensively been used for agriculture. This study investigates the pollution levels with heavy metals in agricultural soils from the Liwa area. Thirty-two soil samples were analyzed for Mn, Zn, Cr, Ni, Cu, Pb, Cd, Co, and As. Results revealed that heavy metal levels varied in the ranges 220.02– 311.21, 42.39–66.92, 43.43–71.55, 32.86–52.12, 10.29–21.70, 2.83–8.84, 0.46–0.69, 0.03–0.37 mg/kg for Mn, Zn, Cr, Ni, Cu, Pb, Cd, Co, and As, respectively. All samples presented low As concentrations with an average of 0.01 mg/kg. The variations …


Soils Laboratory Manual: K-State Edition, Version 2.0, Colby J. Moorberg, David A. Crouse Feb 2021

Soils Laboratory Manual: K-State Edition, Version 2.0, Colby J. Moorberg, David A. Crouse

NPP eBooks

The Soils Laboratory Manual, K-State Edition is designed for students in undergraduate, introductory soil science courses. The manual highlights the multidisciplinary aspects of soil science with laboratories focused on soil formation, classification, and mapping; soil physics, soil biology; soil chemistry; and soil fertility and management. The lab manual includes 16 different laboratories, each one starting with an introduction and pre-lab assignment, followed by in-lab activities, and complimented by a post-lab assignment. In-lab activities involve field trips, experiments, observation stations, or problem sets. Post-lab assignments include online quizzes, problem sets, or laboratory summary reports.

Version 2 of the lab manual exhibits …


The Effects Of Increasing Doses Of Nickel And Lead Applications On Some Oriental Tobacco Varieties, Mahmut Tepeci̇k, Mehmet Eşref İrget Jan 2021

The Effects Of Increasing Doses Of Nickel And Lead Applications On Some Oriental Tobacco Varieties, Mahmut Tepeci̇k, Mehmet Eşref İrget

Turkish Journal of Agriculture and Forestry

Heavy metals are hazardous pollutants for humans, animals and plants, when their threshold concentration exceeds. Tobacco can accumulate higher concentrations of heavy metals, and the genotypic differences of tobacco in heavy metal uptake and their growth responses have not been clearly examined. In this study, the effects of nickel (Ni) and lead (Pb) on phytoremediation capabilities were tested in four local Oriental tobacco cultivars (Basma, Akhisar, Sarıbağlar and Dibek). In two pot experiments, nitrogen (N), phosphorus (P) and potassium (P) were applied in fıxed doses, while Pb and Ni were applied at 4 different doses (10, 50, 100 and 150 …


Determining The Effects Of Imidacloprid On Non-Target Soil Organisms In Hemlock Stands, Braley Burke Jan 2021

Determining The Effects Of Imidacloprid On Non-Target Soil Organisms In Hemlock Stands, Braley Burke

Graduate Theses, Dissertations, and Problem Reports

The hemlock woolly adelgid (HWA), Adelges tsugae Annand (Hemiptera: Adelgidae), is an invasive insect that is causing mortality of eastern hemlock trees, Tsuga canadensis, and Carolina hemlock trees, Tsuga caroliniana, across the eastern United States. To protect these ecologically important tree species, a neonicotinoid insecticide, imidacloprid, is commonly used. Imidacloprid is an effective treatment and can remain effective against HWA for four to six years but long-term (≥ one year after application) non-target effects of imidacloprid on forest ecosystems are not well-studied. This study examined terrestrial non-target effects of imidacloprid in hemlock stands with different treatment histories to …


The Effects Of Priming Eruca Sativa Seeds With Short-Chain Ahl C6-Hsl At Bard Farm, Shannon M. Ryan Jan 2021

The Effects Of Priming Eruca Sativa Seeds With Short-Chain Ahl C6-Hsl At Bard Farm, Shannon M. Ryan

Senior Projects Spring 2021

Many gram-negative bacteria use quorum sensing to assess population densities and cooperate with another. The quorum sensing autoinducers N-acyl homoserine lactones (AHLs) have been found to cause altered gene expression patterns in plants, resulting in increased root and shoot growth as well as induced pathogenic resistance in various species. Researchers have begun exploring the ways AHLs may be used in agricultural systems to reduce the use of environmentally harmful synthetic fertilizers and pesticides. In this study, the effect of priming arugula (Eruca sativa) seeds with the short-chain AHL C6-HSL was investigated at Bard Farm in Annandale-On-Hudson, New York. Leaf lengths …


Evaluation Of Nitrous Oxide Emissions From Furrow-Irrigated Rice On A Silt-Loam Soil In Arkansas, Jordan M. Slayden Jan 2021

Evaluation Of Nitrous Oxide Emissions From Furrow-Irrigated Rice On A Silt-Loam Soil In Arkansas, Jordan M. Slayden

Graduate Theses and Dissertations

As the number one rice (Oryza sativa)-producing state in the United States, Arkansas also ranks fourth as the largest user of groundwater. Recently, due to the development of drought- resistant hybrid cultivars, the furrow-irrigated rice production system has become an increasingly popular alternative to traditional flood-irrigated production with respect to conserving groundwater and maintaining yield. However, other environmental parameters, like greenhouse gas emissions, specifically nitrous oxide (N2O), have yet to be evaluated under furrow-irrigated rice. The objectives of this study were to i) evaluate the effects of site position (i.e., up-, mid-, and down-slope) and tillage treatment [i.e., conventional tillage …


Mycorrhizal Type Dictates Soil Microbial Diversity And Function And The Integrated Root-Microbial Response To Water Stress In Temperate Forests, Nanette C. Raczka Jan 2021

Mycorrhizal Type Dictates Soil Microbial Diversity And Function And The Integrated Root-Microbial Response To Water Stress In Temperate Forests, Nanette C. Raczka

Graduate Theses, Dissertations, and Problem Reports

Our understanding of the mechanisms that control the magnitude of the temperate forest carbon (C) sink and its response to global change remain uncertain. Much of this uncertainty lies in the extent to which differences between tree species in their mycorrhizal symbionts and corresponding nutrient acquisition strategies control the activity of soil microbes that mobilize nutrients and decompose soil organic matter. ECM trees allocate substantial amounts of C to ECM fungi and rhizosphere microbes to mine soil organic matter for nutrients. By contrast, AM trees invest less C belowground and rely on AM fungi to scavenge for nutrients. While these …


Metagenomic Identification And Classification Of The Mercury-Methylating Gene Hgca In Response To Water Table And Plant Functional Group Manipulations In Peat Soil, Madeline Peterson Jan 2021

Metagenomic Identification And Classification Of The Mercury-Methylating Gene Hgca In Response To Water Table And Plant Functional Group Manipulations In Peat Soil, Madeline Peterson

Dissertations, Master's Theses and Master's Reports

Methyl-mercury (MeHg) is a potent neurotoxin that threatens the health of humans and wildlife alike. Climate warming threatens to shift regional precipitation and climate regimes in peatland environments, which could destabilize northern peatlands and accelerate both Hg release from soil and MeHg production. Peatlands are among the leading hotspots for MeHg, yet little is known about the community composition or functional relationship of mercury-methylating microbes in response to varying environmental conditions. The recognized mercury-methylating genes responsible for this activity are the obligatory gene pair hgcA and hgcB. Metagenomic data from the full-factorial peatland mesocosm experiment PEATcosm was obtained to …


Shaping Soil: Examining Relationships Between Agriculture And Climate Change, Lindsay Barbieri Jan 2021

Shaping Soil: Examining Relationships Between Agriculture And Climate Change, Lindsay Barbieri

Graduate College Dissertations and Theses

As the ripple-effects of a changing climate shape our planet, understanding relationships between agriculture and climate change is critical. With agricultural practices shaping soils on over a third of the earth’s land surface, the soils and lands where food is produced are integral grounds for examining these relationships. While not all humans practice agriculture in similar or damaging ways, nevertheless, dominant agricultural practices are displacing beings and ecosystems and perturbing global nutrient cycles across the planet. These entwined imbalances of dominance and nutrients result in flows of excess nitrogen, phosphorus, and carbon that are responsible for nearly three-fourths of the …