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Articles 6241 - 6270 of 9408
Full-Text Articles in Entire DC Network
Pranked By Audubon: Constantine S. Rafinesque’S Description Of John James Audubon’S Imaginary Kentucky Mammals, Neal Woodman
Pranked By Audubon: Constantine S. Rafinesque’S Description Of John James Audubon’S Imaginary Kentucky Mammals, Neal Woodman
United States Geological Survey: Staff Publications
The North American naturalist Constantine S. Rafinesque spent much of the year 1818 engaged in a solo journey down the Ohio River Valley to explore parts of what was then the western United States. Along the way, he visited a number of fellow naturalists, and he spent more than a week at the Henderson, Kentucky, home of artist and ornithologist John James Audubon. During the succeeding two years, Rafinesque published descriptions of new species that resulted from his expedition, including eleven species of fishes that eventually proved to have been invented by Audubon as a prank on the credulous naturalist. …
Seasonal Evolution Of Active Layer Formation In Subarctic Peat Plateaux And Implications For Dissolved Organic Matter Composition And Transfer, Jennifer L. Hickman
Seasonal Evolution Of Active Layer Formation In Subarctic Peat Plateaux And Implications For Dissolved Organic Matter Composition And Transfer, Jennifer L. Hickman
Theses and Dissertations (Comprehensive)
Peat-accumulating wetlands are ecosystems whose rate of photosynthetic production of organic matter is greater than that of its decomposition, resulting in a build up of soil organic matter that may take centuries to fully decompose. Carbon (C) stocks within these ecosystems are a function of inputs from photosynthesis, and losses from heterotrophic decomposition. Due to the short growing season and overall cold climate of boreal and tundra regions, C has been accumulating within these landscapes, mostly in soil organic matter, since the last glaciation. Climate change, predicted to result in rising temperatures and increased precipitation, has begun to degrade the …
Adsorption Of Antibiotics By Vermiculite, Mosa J. Ferdous
Adsorption Of Antibiotics By Vermiculite, Mosa J. Ferdous
Dissertations and Theses
The occurrence of residual antibiotics in the environment has been a worldwide issue and warrants the development of inexpensive yet effective methods for antibiotics removal from contaminated water. In this thesis work, the adsorption of four antibiotics, namely chlorotetracycline (CTC), oxytetracycline (OTC), ofloxacin (OFL), and enrofloxacin (ENR), onto natural vermiculite has been studied using batch (static) and column (dynamic) adsorption techniques. The Langmuir and Freundlich isotherm models were initially used to explain the adsorption processes. The separation factor (RL) values derived from the Langmuir model and the 1/n values derived from Freundlich model in the present investigation were less than …
Assessing The Utility Of Imaging Radar For Identifying White Sand Vegetation Structure, Jessica Rosenqvist
Assessing The Utility Of Imaging Radar For Identifying White Sand Vegetation Structure, Jessica Rosenqvist
Dissertations and Theses
White sand vegetation communities are wide spread across South America; found in Peru, Venezuela, Brazilian Amazon and Guyana. They are distributed in patches ranging from <1 km2 to greater than tens of square kilometers and their origins and locations are still not well understood. The communities are related to a variety of factors (soil type, flooding, nutrient content and fire); hence a precise definition for the ecosystem is still not fully defined. Nevertheless, the result of these variations creates a unique environment for endemic plant and animal species to thrive. Furthermore, analysis of these areas has been very scattered and identification of local white sand areas (<1 km2) have not been accomplished. In addition, identification of these locations has currently only used optical satellite imagery (Landsat, MODIS). Hence, in this project, we have attempted to use synthetic aperture radar to create a classification system to locate the white sand vegetation systems. The goal is to be able to apply this method to identify white sand vegetation distribution across South America. The region of focus for this thesis has been in Aracá, a large white sand area located in Brazil in the State of Amazonas. Due to the lack of ground reference data, a classified map by Capurucho et al. (2013), generated using Landsat data, was used as a comparison and reference. JAXA’s ALOS-1 PALSAR (L-band), ESA’s Sentinel-1A (C-band) and NASA’s SRTM sensors were used for land classification. As microwave signals penetrate clouds and haze, the advantage of using sensors with this wavelength allows for an unobstructed coverage of the landscape all year round. Different combinations of polarizations and wavelengths were used during the analysis to try and separate the white sand vegetation from water and terra firme forest. The resulting classification images showed a 30% agreement with the classification map by Capurucho et al. It is important to note, that this number is in fact an agreement percentage as the map used was a classification image and coarse in resolution (due to the lack of reference data). Therefore, this value does not imply a bad classification. Future work will include time-series data, precise ground reference points and data from other sensors such as ALOS-2 PALSAR, to improve the classification accuracy.
Geologic Time, John J. Renton, Thomas Repine
Geologic Time, John J. Renton, Thomas Repine
Readings and Notes
It is not surprising that humans have wondered how long Earth has existed. At one extreme, there were the Brahmans of India who believe that Earth never had a beginning and will never have an end. Others were of the opinion that Earth was old, but perhaps not eternally old. In 450 BC, for example, a Greek historian named Herodotus (484 - 425 BC) expressed the opinion that Earth was very old, basing his estimate on the results of his studies of the Nile Delta. He observed that the delta was growing layer by layer as a result of the …
Earthquakes, John J. Renton, Thomas Repine
Earthquakes, John J. Renton, Thomas Repine
Readings and Notes
For centuries, earth scientists have known where the major earthquakes occurred. They also knew they occurred in the same locales as the most violent volcanoes, a fact that led to centuries of arguments as to which was the cause of the other. Now we know that they are not cause and effect; they are both associated with the convergent plate margins. During the mid-1900s, another major zone of both volcanic and earthquake activity was discovered, namely the divergent margins, the most important site being the oceanic ridges. Since then, we have also come to understand the occurrence of volcanic activity …
The Triassic Period And The Beginning Of The Mesozoic Era, John J. Renton, Thomas Repine
The Triassic Period And The Beginning Of The Mesozoic Era, John J. Renton, Thomas Repine
Readings and Notes
The Triassic Period is the first period of the Mesozoic Era, a span of time from 245 million years ago to 66 million years ago. Although the Mesozoic era commonly known as the "Age of the Dinosaurs,', it should be pointed out that there were other important evolutionary developments taking place such as the appearance of the first mammal birds and flowering plans. The onset of the Mesozoic Era, the Triassic Period, was also a time of profound tectonic activity affecting the entire North American craton. In the east, the primary event was the breakup of Pangea and the formation …
Geographically Isolated Wetlands Are Part Of The Hydrological Landscape, Mark Rains, S. G. Leibowitz, M. J. Cohen, I. F. Creed, H. E. Golden, J. W. Jawitz, P. Kalla, C. R. Lane, M. W. Lang, D. L. Mclaughlin
Geographically Isolated Wetlands Are Part Of The Hydrological Landscape, Mark Rains, S. G. Leibowitz, M. J. Cohen, I. F. Creed, H. E. Golden, J. W. Jawitz, P. Kalla, C. R. Lane, M. W. Lang, D. L. Mclaughlin
School of Geosciences Faculty and Staff Publications
No abstract provided.
Synergistic Effects Of Climate Change And Grazing On Net Primary Production Of Mongolian Grasslands, Shree R. S. Dangal, Hanqin Tian, Chaoqun Lu, Shufen Pan, Neil Pederson, Amy Hessl
Synergistic Effects Of Climate Change And Grazing On Net Primary Production Of Mongolian Grasslands, Shree R. S. Dangal, Hanqin Tian, Chaoqun Lu, Shufen Pan, Neil Pederson, Amy Hessl
Faculty & Staff Scholarship
In arid and semi-arid regions, grassland degradation has become a major environmental and economic problem, but little information is available on the response of grassland productivity to both climate change and grazing intensity. By developing a grazing module in a process-based ecosystem model, the dynamic land ecosystem model (DLEM), we explore the roles of climate change, elevated CO2, and varying grazing intensities in affecting aboveground net primary productivity (ANPP) across different grassland sites in Mongolia. Our results show that both growing season precipitation totals and average temperature exert important controls on annual ANPP across six sites over a precipitation gradient, …
Geophysical Imaging Of Karst Features In Missouri, Jeremiah Chukwunonso Obi
Geophysical Imaging Of Karst Features In Missouri, Jeremiah Chukwunonso Obi
Doctoral Dissertations
"Automated electrical resistivity tomography (ERT) supported with multichannel analysis of surface waves (MASW) and boring data were used to map karst related features in Missouri in order to understand karst processes better in Missouri. Previous works on karst in Missouri were mostly surficial mapping of bedrock outcrops and joints, which are not enough to define the internal structure of karst system, since most critical processes in karst occur underground. To understand these processes better, the density, placement and pattern of karst related features like solution-widened joints and voids, as well as top of bedrock were mapped. In the course of …
Marine Ecoregion And Deepwater Horizon Oil Spill Affect Recruitment And Population Structure Of A Salt Marsh Snail, Steven C. Pennings, Scott Zengel, Jacob Oehrig, Merryl Alber, T. Dale Bishop, Donald R. Deis, Donna Devlin, A. Randall Hughes, John J. Hutchens, Jr., Whitney M. Kiehn, Caroline R. Mcfarlin, Clay L. Montague, Sean P. Powers, C. Edward Proffitt, Nicholle Rutherford, Camille L. Stagg, Keith Walters
Marine Ecoregion And Deepwater Horizon Oil Spill Affect Recruitment And Population Structure Of A Salt Marsh Snail, Steven C. Pennings, Scott Zengel, Jacob Oehrig, Merryl Alber, T. Dale Bishop, Donald R. Deis, Donna Devlin, A. Randall Hughes, John J. Hutchens, Jr., Whitney M. Kiehn, Caroline R. Mcfarlin, Clay L. Montague, Sean P. Powers, C. Edward Proffitt, Nicholle Rutherford, Camille L. Stagg, Keith Walters
University Faculty and Staff Publications
Marine species with planktonic larvae often have high spatial and temporal variation in recruitment that leads to subsequent variation in the ecology of benthic adults. Using a combination of published and unpublished data, we compared the population structure of the salt marsh snail, Littoraria irrorata, between the South Atlantic Bight and the Gulf Coast of the United States to infer geographic differences in recruitment and to test the hypothesis that the Deepwater Horizon oil spill led to widespread recruitment failure of L. irrorata in Louisiana in 2010. Size-frequency distributions in both ecoregions were bimodal, with troughs in the distributions consistent …
Reconstructing Dinosaur Foot Tracks And Identifying New Footprints Using Structure From Motion Photogrammetry, Valeria V. Martinez
Reconstructing Dinosaur Foot Tracks And Identifying New Footprints Using Structure From Motion Photogrammetry, Valeria V. Martinez
Open Access Theses & Dissertations
The use of 3-D Structure from Motion models to study fossils is a relatively new technique that has an advantage over traditional field methods, such as plaster casts or collecting samples, because it is non-destructive and can be easily shared with a wide audience. It is also ideal for use with persons with disabilities because it does not require field access and it can be manipulated for optimum computer viewing or printed with a 3-D printer for tactile examination as needed. Our study focused on a known site in Cristo Rey, New Mexico where Cretaceous Iguanadon and Ankylosaur footprints have …
Soil Organic Matter Distribution In A Douglas-Fir-Tanoak Forest, Humboldt County, California, Hollie A. Ernest
Soil Organic Matter Distribution In A Douglas-Fir-Tanoak Forest, Humboldt County, California, Hollie A. Ernest
Cal Poly Humboldt theses and projects
Soil carbon (C) affects the active gases in the atmosphere, nutrient cycling, and diversity of flora and fauna. Soil organic matter (SOM) is partially comprised of C, and a widely-accepted ratio of 0.58 organic carbon (OC) to organic matter (OM) is used to measure soil C on a landscape scale. However, this ratio varies according to vegetation, depth, hydrology, and may lead to miscalculations of soil C and SOM estimates. Soil C and SOM are inherently complex and it is not completely understood which environmental factors have the most influence in their formation, which occurs on a time scale of …
Estimated Grass Grazing Removal Rate In A Semiarid Eurasian Steppe Watershed As Influenced By Climate, Xixi Wang, Shohreh Pedram, Tingxi Liu, Ruizhong Gao, Fengling Li, Yanyun Luo
Estimated Grass Grazing Removal Rate In A Semiarid Eurasian Steppe Watershed As Influenced By Climate, Xixi Wang, Shohreh Pedram, Tingxi Liu, Ruizhong Gao, Fengling Li, Yanyun Luo
Civil & Environmental Engineering Faculty Publications
Grazing removal rate of grasses needs to be determined for various climate conditions to address eco-environmental concerns (e.g., desertification) related to steppe grassland degradation. The conventional approach, which requires survey data on animal species and heads as well as grass consumption per individual animal, is too costly and time-consuming to be applied at a watershed scale. The objective of this study was to present a new approach that can be used to estimate grazing removal rate with no requirement of animal-related data. The application of this new approach was demonstrated in a Eurasian semiarid typical-steppe watershed for an analysis period …
Evaluating The Biogeochemical Functioning Of A Constructed Fen On The Post-Mining Landscape Of Athabasca Oil Sands Region, Fort Mcmurray, Alberta, Canada, Felix C. Nwaishi
Evaluating The Biogeochemical Functioning Of A Constructed Fen On The Post-Mining Landscape Of Athabasca Oil Sands Region, Fort Mcmurray, Alberta, Canada, Felix C. Nwaishi
Theses and Dissertations (Comprehensive)
Peatlands have a unique biogeochemical function, characterized by an imbalance between the rates of biomass accumulation and decomposition. These characteristics facilitate the ability of peatlands to support the sequestration of nutrients and carbon. In disturbed peatlands, these functions are compromised. Thus, reclamation targets amongst other key functions, the recovery of biogeochemical functioning. These functions could serve as a measure of recovery to conditions that are present in natural analogues. This thesis examines the recovery of microbially-mediated nutrient transformation processes in a fen peatland that was constructed on a post-mining landscape in the Athabasca oil sands region, Fort McMurray, Alberta. The …
Spanish River Carbonatite: Its Benefits And Potential Use As A Soil Supplement In Agriculture, James J
Spanish River Carbonatite: Its Benefits And Potential Use As A Soil Supplement In Agriculture, James J
Theses and Dissertations (Comprehensive)
A critical problem facing agriculture today is being able to consistently and sustainably provide plants with adequate nutrients for growth. With this problem being exacerbated by the ever-increasing human population, new perspectives and techniques are required to ensure global food security. In order to fully realize potential solutions, however, plant growth and nutrition cannot be exclusively focused upon. The soil-microorganism-plant system is comprised of many interconnected and interdependent processes that together support plant growth: it is upon these processes that the focus must be placed. In this work, the agromineral Spanish River Carbonatite (SRC) is characterized using the framework of …
Integrated Geophysical Approach Using Electrical Resistivity Tomography And Multichannel Analysis Of Surface Wave In Assessing Wilson Spring Development, Ibrahim E. Ahmed
Integrated Geophysical Approach Using Electrical Resistivity Tomography And Multichannel Analysis Of Surface Wave In Assessing Wilson Spring Development, Ibrahim E. Ahmed
Doctoral Dissertations
"This research investigated fractured zones leading to preferential flow paths of Wilson Spring. In this context, electrical resistivity tomography (ERT) data and multi-channel analyses of surface waves (MASW) data were acquired at studied site with the purpose of mapping a variable depth to top of bedrock and geological structures.
Interpretation of the boreholes, MASW, and ERT data indicated that a depth to top of rock does vary significantly at the studied site due to many solution-widened fractures. Multiple near-vertical solution-widened fractures were mapped in the studied site based on the interpretation of the ERT data. The mapped solution-widened fractures appear …
Palynological Studies Of Holocene Lake Sediments In The Missouri Ozarks, Robert D. Haselwander
Palynological Studies Of Holocene Lake Sediments In The Missouri Ozarks, Robert D. Haselwander
Doctoral Dissertations
"Five small lakes in southeast Missouri (Frisco, Pine Forest, and Bray Area lakes [Phelps County], and Cypress and Blue ponds [Bollinger County]) were cored for paleolimnological studies. Cores were evaluated for their sedimentology, palynology, and geochemistry. In two of these lakes (Bray Area and Pine Forest lakes) the planktonic algae were also studied in the water column, along with ecological parameters. Algae in the sediments were compared to algae in the water to understand the resistance of different species to decay, and a suggested methodology for this work is described. Reconstructions of the past environments around each lake were created …
2d Seismic Data And Gas Chimney Interpretation In The South Taranaki Graben, New Zealand, Taqi Talib Alzaki
2d Seismic Data And Gas Chimney Interpretation In The South Taranaki Graben, New Zealand, Taqi Talib Alzaki
Masters Theses
"The Taranaki Basin is one of the major oil and gas producing basins offshore New Zealand. The study area covers an area of 10,000 km2 in the basin, and includes 171 2D seismic lines and six wells, which are provided by the New Zealand Petroleum & Minerals. Some previous studies refer to the study area as the South Taranaki Graben.
This thesis provides detailed mapping and interpreted subsurface stratigraphy and structure of five horizons, i.e. basement top, Pakawau Group top, Kapuni Group top, Wai-iti Group top, and seafloor. It undertakes studies of the relation between the basin evolution, faults, …
Avon Alkaline Igneous Province, Missouri: Characterization Of Subcontinental Mantle Source And Evolution Via Chemical Analysis Of Olivine, Zachary William Freeman
Avon Alkaline Igneous Province, Missouri: Characterization Of Subcontinental Mantle Source And Evolution Via Chemical Analysis Of Olivine, Zachary William Freeman
Masters Theses
"This article presents the crystallization age of, and composition of olivine phenocrysts within an alnoite of, the Avon Alkaline Igneous Province (AAIP) of Ste. Genevieve County, Missouri. The AAIP is an ultramafic igneous province consisting of approx. 80 known intrusives of diverse lithology and texture. 40Ar/39 Ar geochronology indicates an emplacement age of 386 +/- 1 Ma, which establishes the AAIP as the only known Devonian-age ultramafic igneous body in the Midwestern U.S. Study of the AAIP provides a unique opportunity to characterize the Devonian-age subcontinental mantle and the processes that generated the suite of ultramafic rocks present …
The Effects Of Blended Learning On Critical Thinking In A High School Earth Science Class, Renee Nicole Borglum
The Effects Of Blended Learning On Critical Thinking In A High School Earth Science Class, Renee Nicole Borglum
Dissertations and Theses @ UNI
This study analyzed the effects of differing levels of technology use in a high school Earth Science class on student performance on the Classroom Test of Scientific Reasoning (CTSR). Blended learning manipulates the combination of hands-on activities, classroom discussions, online discussions, interactive simulations and a variety of assessments that engage, instruct and assess student learning. Critical thinking is the set of skills and dispositions that foster problem solving, reasoning ability and selfregulation. The increasing use of technology in the classroom and fluctuation of content standards prompted this research. The results have implications for the classroom teacher of a wide range …
Small-Scale Biogeographic Patterns Of Benthic Bacterial And Ciliate Communities In The Saline Ponds Of Lake Macleod, North-Western Australia, Christopher Kavazos
Small-Scale Biogeographic Patterns Of Benthic Bacterial And Ciliate Communities In The Saline Ponds Of Lake Macleod, North-Western Australia, Christopher Kavazos
Theses: Doctorates and Masters
This biogeographical thesis tests for the presence of taxa-area and distance-decay relationships, which are common among macrobionts, in prokaryotic (bacterial) and micro-eukaryotic (ciliate) communities. Microbial biogeographical patterns may be distinct because of the high abundances, diversity and dispersal capabilities of microbes, in comparison to macrobionts. The Northern Ponds of Lake MacLeod, north-western Australia, provide an ideal location to address this topic, because the ponds are effectively hydrogeomorphologically identical, other than in surface area, and biotic histories can be assumed to differ only according to distance of separation. This means that hypotheses concerning species-sorting and neutral processes on microbial assemblages can …
Juvenile Survival And Adult Return As A Function Of Freshwater Rearing Life History For Coho Salmon In The Klamath River Basin, Molly Gorman
Juvenile Survival And Adult Return As A Function Of Freshwater Rearing Life History For Coho Salmon In The Klamath River Basin, Molly Gorman
Cal Poly Humboldt theses and projects
The Scott and Shasta rivers, Klamath River tributaries, experience spatial disparity in habitat quality in spring and summer as a result of historical and current land-use. Juvenile Coho Salmon (Oncorhynchus kisutch) born in the upper tributary reaches often rear in natal streams before migrating to sea. However, those born in the lower reaches often encounter unsuitable habitat and emigrate during their first spring to seek non-natal rearing habitats. It is assumed that these early outmigrants are population losses. This study evaluated first-summer survival, and contribution to the adult population, of non-natal rearing juveniles in the Klamath River Basin. …
Automatic Detection And Quantification Of Bluff Erosion Events In Single Image Series, Martin D. Hellwig
Automatic Detection And Quantification Of Bluff Erosion Events In Single Image Series, Martin D. Hellwig
Graduate Masters Theses
Many communities along coastlines and riverbanks are threatened by water erosion and hence an accurate model to predict erosion events is needed in order to plan mitigation strategies. Such models need to rely on readily available meteorological data that may or may not be correlated with the occurrence of erosion events. In order to accurately study these potential correlations, researchers need a quantified time series index indicating the occurrence and magnitude of erosion in the studied area. We show that such an index can be obtained by creating and analyzing a single image series using relatively cheap consumer grade digital …
A Desert In Disguise: The Resilience Of The Nebraska Sandhills, Jeff Hartman
A Desert In Disguise: The Resilience Of The Nebraska Sandhills, Jeff Hartman
School of Natural Resources: Dissertations, Theses, and Student Research
The Nebraska Sandhills are the largest sand dune system in the Western Hemisphere, and are unique because they remain relatively undisturbed from row crop agriculture. Research in the past two decades demonstrated that the Sandhills are dynamic on millennial timescales, switching between stabilized, vegetated states to non-vegetated, mobilized states. The Sandhills are currently stabilized, but understanding how ecological processes are altered as sand dunes transition from stabilized to mobilized states, provides insight into the thresholds, stability, and resilience of this grassland ecosystem. My research investigated the impacts of vegetation disturbances on ecological processes and the sand dune surface stability. For …
Phosphorus Release Potential Of Agricultural Soils Of The United States, Rebecca A. Young
Phosphorus Release Potential Of Agricultural Soils Of The United States, Rebecca A. Young
School of Natural Resources: Dissertations, Theses, and Student Research
Phosphorus (P) is one of the leading causes of surface water quality decline in the United States, leading to algal blooms and hypoxia in lakes and streams. Decreasing conservation funds dictate that agencies such as the Natural Resources Conservation Service, maximizes its effectiveness and efficiency in implementing practices to address P management and runoff on agricultural lands. Additional information on P behavior in soil is needed to improve P management plans to reduce pollution risk at the watershed, farm, and field scales. This research focuses on the development of total soil P release models, to be included into assessment and …
Response Of Fishes To Restoration Projects In Bayou St. John Located Within The City Of New Orleans, Louisiana, Including Hydrological Characterization And Hydrodynamic Modelling, Patrick W. Smith
LSU New Orleans Theses and Dissertations
Quantifying the impacts of restoration on coastal waterways is crucial to understanding their effectiveness. Here, I look at the impacts of multiple restoration projects on urban waterways within the city limits of New Orleans, LA, with an emphasis on the response of fishes. First I report the effects of two projects designed to improve exchange down estuary on the hydrologic characteristics of Bayou St. John (BSJ). Within BSJ, flow is dominated by subtidal wind driven processes. Removal of an outdated flood control structure did not appear to alter exchange in BSJ, but removal combined with sector gate openings did. I …
The Role Of The State, Multinational Oil Companies, International Law & The International Community: Intersection Of Human Rights & Environmental Degradation Climate Change In The 21st Century Caused By Traditional Extractive Practices, The Amazon Rainforest, Indigenous People And Universal Jurisdiction To Resolve The Accountability Issue, Marcela Cabrera Luna
Master's Theses
Local, national and international conventions that protect indigenous sovereignty and their territories, where many of the resources are extracted from by multinational corporations (MNCs) particularly oil, the number one commodity of the world and cause of climate change, continue to be jeopardized because of the lack of a clear international legal framework that can protect them and potentially hold multinationals accountable for their actions. These practices are causing not only environmental issues to the indigenous and surrounding communities, but climate change is in fact, the real human rights issue of the 21st century and it affects everyone. By using …
Mitigating N2o Emissions From Soil: From Patching Leaks To Transformative Action, C. Decock, Juhwan Lee, M. Necpalova, Engil Isadora Pujol Pereira, D. M. Tendall, Johan Six
Mitigating N2o Emissions From Soil: From Patching Leaks To Transformative Action, C. Decock, Juhwan Lee, M. Necpalova, Engil Isadora Pujol Pereira, D. M. Tendall, Johan Six
School of Earth, Environmental, & Marine Sciences Faculty Publications
Further progress in understanding and mitigating N2O emissions from soil lies within transdisciplinary research that reaches across spatial scales and takes an ambitious look into the future.
Understanding The Impact Of Intensive Horticulture Land-Use Practices On Surface Water Quality In Central Kenya, Faith K. Muriithi, Danlin Yu
Understanding The Impact Of Intensive Horticulture Land-Use Practices On Surface Water Quality In Central Kenya, Faith K. Muriithi, Danlin Yu
Department of Earth and Environmental Studies Faculty Scholarship and Creative Works
Rapid expansion of commercial horticulture production and related activities contribute to declining surface water quality. The study sought to understand the impacts on select rivers in Laikipia and Meru, production hotspots. The specific aims were (1) to identify prevailing surface water quality by examining variations of 14 physico-chemical parameters, and (2) to categorize measured surface water quality parameters into land use types highlighting potential pollutant source processes. Water samples were collected in July and August 2013 along 14 rivers in the study area. The data were analyzed using principal component analysis (PCA) and discriminant analysis (DA). Principal components (PCs) explained …