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Articles 12451 - 12480 of 17799
Full-Text Articles in Entire DC Network
Introducing And Evaluating A Knowledge Transfer Approach To Support Problem Solving In And Around Protected Areas, Brady J. Mattsson, Marie Fischborn, Mark W. Brunson, Harald Vacik
Introducing And Evaluating A Knowledge Transfer Approach To Support Problem Solving In And Around Protected Areas, Brady J. Mattsson, Marie Fischborn, Mark W. Brunson, Harald Vacik
Environment and Society Faculty Publications
Protected areas (PAs) can generate many benefits inside and outside their borders, and achieving objectives for diverse stakeholders raises many challenges. There are many examples of successful PA management around the globe, although a systematic and comprehensive approach to developing and sharing these solutions has been lacking. We present “solutioning” as a structured process of peer-learning, which can inform management strategies in and around protected areas. We explain how the PANORAMA—Solutions for a Healthy Planet initiative has put solutioning into practice through an interactive community and web portal to learn about protected area solutions around the globe. Unlike other web …
Application Of Modern Foraminiferal Assemblages To Paleoenvironmental Reconstruction: Case Studies From Coastal And Shelf Environments, Christian Haller
Application Of Modern Foraminiferal Assemblages To Paleoenvironmental Reconstruction: Case Studies From Coastal And Shelf Environments, Christian Haller
USF Tampa Graduate Theses and Dissertations
The aim of paleoenvironmental studies is to reconstruct characteristics of the past environment from fossil assemblages preserved in sedimentary strata. Thus, studies of modern surface assemblages, quantitatively correlated to the environmental parameters, are required before reliable interpretations can be made. For this dissertation, two different techniques were applied in two case studies: a reconstruction making use of a benthic foraminiferal transfer function from the intertidal marshes in the eastern Mississippi Sound, Alabama/Mississippi, and a qualitative reconstruction of ocean current activity on the Western Australian shelf.
Modern salt-marsh foraminifera were collected from Grand Bay, Pascagoula, Fowl River, and Dauphin Island across …
Remote Sensing And Spatial Metrics For Quantifying Seagrass Landscape Changes: A Study On The 2011 Indian River Lagoon Florida Seagrass Die-Off Event, René Dieter Baumstark
Remote Sensing And Spatial Metrics For Quantifying Seagrass Landscape Changes: A Study On The 2011 Indian River Lagoon Florida Seagrass Die-Off Event, René Dieter Baumstark
USF Tampa Graduate Theses and Dissertations
Florida’s seagrasses are ecologically important marine environments which have suffered major degradation caused by increasing anthropogenic pressures. A 2011 seagrass die-off event caused by an algal bloom in the Florida Indian River Lagoon (IRL) was particularly severe with a majority of seagrass lost in areas such as the Banana River. An understanding of how this coastal marine environment changed is an important step toward better managing resources for conservation. Modern tools and methods provide new opportunities to study these changes at the landscape scale, a scale that informs on the larger more comprehensive state of a system. Classified satellite imagery …
An Analytical Framework For The Steady State Impact Of Carbonate Compensation On Atmospheric Co2, Anne Willem Omta
An Analytical Framework For The Steady State Impact Of Carbonate Compensation On Atmospheric Co2, Anne Willem Omta
Faculty Scholarship
The deep-ocean carbonate ion concentration impacts the fraction of the marine calcium carbonate production that is buried in sediments. This gives rise to the carbonate compensation feedback, which is thought to restore the deep-ocean carbonate ion concentration on multimillennial timescales. We formulate an analytical framework to investigate the impact of carbonate compensation under various changes in the carbon cycle relevant for anthropogenic change and glacial cycles. Using this framework, we show that carbonate compensation amplifies by 15–20% changes in atmospheric CO2resulting from a redistribution of carbon between the atmosphere and ocean (e.g., due to changes in temperature, salinity, or nutrient …
Sediment And Plant Dynamics In A Degrading Coastal Louisiana Landscape, Glenn Michael. Suir
Sediment And Plant Dynamics In A Degrading Coastal Louisiana Landscape, Glenn Michael. Suir
LSU Doctoral Dissertations
Alterations to Louisiana’s river systems and local hydrology have resulted in reduced freshwater, sediment, and nutrient inputs into wetland landscapes, causing significant negative impacts on marsh productivity and stability. To combat these losses many restoration projects have been constructed or planned throughout coastal Louisiana. Typical goals of wetland restoration efforts are to conserve, create, or enhance wetland form, and to achieve wetland function that approaches natural conditions. Failure to adequately maintain wetland elevation and hydrology can have serious implications on sedimentation and vegetation processes, which significantly reduces the likelihood of reaching structural and functional targets. Measures of wetland condition have …
Humans Thrived In South Africa Through The Toba Eruption About 74,000 Years Ago, Eugene I. Smith, Zenobia Jacobs, Racheal Johnsen, Minghua Ren, Erich C. Fisher, Simen Oestmo, Jayne Wilkins, Jacob A. Harris, Panagiotis Karkanas, Shelby Fitch, Amber Ciravolo, Deborah Keenan, Naomi Cleghorn, Christine S. Lane, Thalassa Matthews, Curtis W. Marean
Humans Thrived In South Africa Through The Toba Eruption About 74,000 Years Ago, Eugene I. Smith, Zenobia Jacobs, Racheal Johnsen, Minghua Ren, Erich C. Fisher, Simen Oestmo, Jayne Wilkins, Jacob A. Harris, Panagiotis Karkanas, Shelby Fitch, Amber Ciravolo, Deborah Keenan, Naomi Cleghorn, Christine S. Lane, Thalassa Matthews, Curtis W. Marean
Geoscience Faculty Research
Approximately 74 thousand years ago (ka), the Toba caldera erupted in Sumatra. Since the magnitude of this eruption was first established, its effects on climate, environment and humans have been debated1. Here we describe the discovery of microscopic glass shards characteristic of the Youngest Toba Tuff—ashfall from the Toba eruption—in two archaeological sites on the south coast of South Africa, a region in which there is evidence for early human behavioural complexity. An independently derived dating model supports a date of approximately 74 ka for the sediments containing the Youngest Toba Tuff glass shards. By defining the input of shards …
New Records Of Guano-Associated Minerals From Caves In Northwestern Borneo, Donald A. Mcfarlane, Joyce Lundberg
New Records Of Guano-Associated Minerals From Caves In Northwestern Borneo, Donald A. Mcfarlane, Joyce Lundberg
International Journal of Speleology
Recent studies of ancient bat guano deposits in the caves of Gunung Mulu National Park and Niah National Park, Sarawak, Malaysia, have resulted in noteworthy records of phosphate minerals from these environments, including variscite, nano-particulate silica, fluorapatite, and niter.
Legacy Contaminants In The Northern Gulf Of Mexico Shelf, Jessica N. Landry
Legacy Contaminants In The Northern Gulf Of Mexico Shelf, Jessica N. Landry
LSU Master's Theses
The Mississippi River watershed is the third largest in the world and drains from 31 states in the United States. Due to its route through the U.S., it passes through hundreds of EPA labeled Superfund sites as well as agricultural and suburban watersheds. These sites are known to have historical chemical contamination, and as a result chemicals can be transported by runoff down the Mississippi River into the Gulf of Mexico where their ultimate fate is unknown. Organochlorine chemicals are known to be persistent and are found in agricultural land as well as US EPA Superfund sites, especially DDT, PCBs, …
The Functional Specialties: A Workshop On Applying Lonergan, Praxis Program Of The Advanced Seminar On Mission, Seton Hall University
The Functional Specialties: A Workshop On Applying Lonergan, Praxis Program Of The Advanced Seminar On Mission, Seton Hall University
Praxis Conference and Workshop Proceedings
These are the proceedings of the Praxis Program of the Advanced Seminar on Mission’s third annual summer workshop which was held in Trieste, Italy in July 2017. It focused on the application of Bernard Lonergan’s Functional Specialties to the work of the Seton Hall University faculty participants. The workshop was jointly sponsored by the Center for Vocation and Servant Leadership and the Center for Catholic Studies, and co-sponsored by Boston College, the Jacques Maritain Institute and the University of Trieste.
Spatial And Temporal Dynamics Of Dissolved Oxygen Concentrations And Bioactivity In The Hyporheic Zone, W. Jeffery Reeder, Annika M. Quick, Tiffany B. Farrell, Shawn G. Benner, Kevin P. Feris, Daniele Tonina
Spatial And Temporal Dynamics Of Dissolved Oxygen Concentrations And Bioactivity In The Hyporheic Zone, W. Jeffery Reeder, Annika M. Quick, Tiffany B. Farrell, Shawn G. Benner, Kevin P. Feris, Daniele Tonina
Geosciences Faculty Publications and Presentations
Dissolved oxygen (DO) concentrations and consumption rates are primary indicators of heterotrophic respiration and redox conditions in the hyporheic zone (HZ). Due to the complexity of hyporheic flow and interactions between hyporheic hydraulics and the biogeochemical processes, a detailed, mechanistic, and predictive understanding of the biogeochemical activity in the HZ has not yet been developed. Previous studies of microbial activity in the HZ have treated the metabolic DO consumption rate constant (KDO) as a temporally fixed and spatially homogeneous property that is determined primarily by the concentration of bioavailable carbon. These studies have generally treated bioactivity as temporally …
Landscapes From The Waves—Marine Terraces Of California, Marjorie Schulz, Corey Lawrence, Daniel R. Muhs, Carol Prentice, Sam Flanagan
Landscapes From The Waves—Marine Terraces Of California, Marjorie Schulz, Corey Lawrence, Daniel R. Muhs, Carol Prentice, Sam Flanagan
United States Geological Survey: Publications
M any coastlines around the world have stair-step landforms, known as marine terraces. Marine terraces make up a large part of coastal California’s landscape—from San Diego to Crescent City. Find out how these landscapes form, why marine terraces are of interest to scientists, and where you can explore these landscapes.
Marine terraces result from the interaction of two geologic processes: uplift of the land surface and the natural rise and fall of sea level over hundreds of thousands of years. As sea level rises, waves move underwater sediment—sand and gravel—back and forth against bedrock, acting like sandpaper to hone bedrock …
City Of Tampa Tree Canopy And Urban Forest Analysis 2016, Shawn M. Landry, Andrew K. Koeser, Robert J. Northrop, Drew Mclean, Geoffrey Donovan, Michael G. Andreu, Deborah Hilbert
City Of Tampa Tree Canopy And Urban Forest Analysis 2016, Shawn M. Landry, Andrew K. Koeser, Robert J. Northrop, Drew Mclean, Geoffrey Donovan, Michael G. Andreu, Deborah Hilbert
School of Geosciences Faculty and Staff Publications
No abstract provided.
Do Precision Chemical Amendment Applications Impact Sodium Movement In Dryland Semiarid Saline Sodic Soils?, Tulsi P. Kharel, David E. Clay, Cheryl Reese, Thomas Desutter, Doug D. Malo, Sharon Clay
Do Precision Chemical Amendment Applications Impact Sodium Movement In Dryland Semiarid Saline Sodic Soils?, Tulsi P. Kharel, David E. Clay, Cheryl Reese, Thomas Desutter, Doug D. Malo, Sharon Clay
Agronomy, Horticulture and Plant Science Faculty Publications
Expanding sodicity and salinity problems have placed many northern Great Plains (NGP) soils at the sustainability tipping point. This study assessed the impact of chemical restoration on water and salt transport in undisturbed soil columns collected from three hillslope model landscape positions. The backslope (Redfield), footslope (White Lake), and toeslope (Pierpont) soils had moderate (3.27 ± 0.59), high (7.3 ± 3.34), and very high (13.29 ± 3.2) sodium adsorption ratio (SARe) values, respectively. The soils were treated with KBr and one of four soil amendments (none, H2SO4, CaSO4, and CaCl2). …
Lithofacies And Sequence Architecture Of The Upper Desert Creek Sequence (Middle Pennsylvanian, Paradox Formation) In The Greater Aneth Field, Southern Paradox Basin, Utah, Evan R. Gunnell
Theses and Dissertations
The Greater Aneth Buildup (GAB) is comprised of the 3rd-order middle Pennsylvanian (Desmoinesian) Desert Creek sequence of the Paradox Formation. A hierarchy of 4th- and 5th order, carbonate-dominated cycles comprise the Upper Desert Creek (UDC) 4th-order sequence. A SE to NW trending transect line, utilizing core and petrophysical data from six oil and gas wells (from SE to NW wells R-19, Q-16, O-16, J-15, K-430, E-313), revealed deposition of seven carbonate facies within four 5th-order parasequences in the UDC. While each of the seven carbonate facies are present across the transect line, the UDC parasequences are dominated by a shallow-water …
Redescription And Phylogenetic Analysis Of The Materials Assigned To The Taxon "Captorhinikos" Chozaensis, Jason Paul Jung
Redescription And Phylogenetic Analysis Of The Materials Assigned To The Taxon "Captorhinikos" Chozaensis, Jason Paul Jung
Electronic Theses, Projects, and Dissertations
“Captorhinikos” chozaensis is a multiple-tooth-rowed captorhinid reptile from the Lower Permian Clear Fork Group, undivided formation. Upon re-examination of the materials associated with the species from both the Chicago Field Museum of Natural History, and the Smithsonian United States National Museum, I reaffirm their affinity and collective identity as a valid taxon. “Captorhinikos” chozaensis does not, however, belong with either of the two members of its genus, C. valensis or “C.” parvus, instead occupying its own branch on the phylogenetic tree of the Captorhinidae. This conclusion is based in strong results from a combined phylogenetic parsimony analysis combined with …
Discovery Of Possible Paleotsunami Deposits In Pangandaran And Adipala, Java, Indonesia Using Grain Size, Xrd, And 14C Analyses, Kevin L. Stuart
Discovery Of Possible Paleotsunami Deposits In Pangandaran And Adipala, Java, Indonesia Using Grain Size, Xrd, And 14C Analyses, Kevin L. Stuart
Theses and Dissertations
Grain size, 14C age, and X-ray diffraction (XRD) analyses of sediments indicate possible tsunami deposits on the southern coast of Java near Pangandaran and Adipala. Previous studies that have described known recent and paleotsunami deposits were used for comparison. Fining-upward grain size trends, interbedded sand and mud, sediment composition, and trends in heavy mineral abundances are among the characteristics used for tsunami deposit identification. At Batu Kalde, an archaeological site south of Pangandaran, a layer of aragonitic sand with marine fossils was found atop a layer of archaeological fragments at an elevation of ~2-5 m. It is likely this …
Carbon Budget Of Tidal Wetlands, Estuaries, And Shelf Waters Of Eastern North America, R. G. Najjar, M. Herrmann, R. Alexander, D. J. Burdige, D. Butman, W.-J. Cai, E. A. Canuel, R. F. Chen, M. A. M. Friedrichs, M. R. Mulholland
Carbon Budget Of Tidal Wetlands, Estuaries, And Shelf Waters Of Eastern North America, R. G. Najjar, M. Herrmann, R. Alexander, D. J. Burdige, D. Butman, W.-J. Cai, E. A. Canuel, R. F. Chen, M. A. M. Friedrichs, M. R. Mulholland
OES Faculty Publications
Carbon cycling in the coastal zone affects global carbon budgets and is critical for understanding the urgent issues of hypoxia, acidification, and tidal wetland loss. However, there are no regional carbon budgets spanning the three main ecosystems in coastal waters: tidal wetlands, estuaries, and shelf waters. Here we construct such a budget for eastern North America using historical data, empirical models, remote sensing algorithms, and process‐based models. Considering the net fluxes of total carbon at the domain boundaries, 59 ± 12% (± 2 standard errors) of the carbon entering is from rivers and 41 ± 12% is from the atmosphere, …
Effects Of Herbivores, Wave Exposure And Depth On Benthic Coral Communities Of The Easter Island Ecoregion, Erin E. Easton, Carlos F. Gaymer, Alan M. Friedlander, James J. Herlan
Effects Of Herbivores, Wave Exposure And Depth On Benthic Coral Communities Of The Easter Island Ecoregion, Erin E. Easton, Carlos F. Gaymer, Alan M. Friedlander, James J. Herlan
School of Earth, Environmental, & Marine Sciences Faculty Publications
The Easter Island ecoregion includes Rapa Nui (Easter Island; RN), with a human population of ~5600, and the uninhabited Salas y Gómez (SyG). Although the culture and terrestrial ecology of RN have been well studied, we know little about the marine environment of these islands, particularly the interplay among herbivores, algae, and corals, and how coral reef communities differ between islands, by wave energy exposure, and between depths. To address the potential roles of herbivores, wave-energy exposure, and depth on the sessile benthic communities, we examined herbivorous fish biomass, sea urchin (Diadema savignyi) density, and algal and coral …
Fertilizing High Producing Alfalfa Stands, Edwin L. Ritchey
Fertilizing High Producing Alfalfa Stands, Edwin L. Ritchey
Kentucky Alfalfa and Stored Forage Conference
There are no secrets for successfully producing a high quality alfalfa crop. Successful alfalfa production is a product of suitable site selection, proper fertility and pH management, good pest control, and favorable weather conditions throughout the season. This paper focuses on proper fertility and pH management practices.
Pre-Spawning Snout-Gripping Behaviors Of Gymnothorax Pictus And Gymnothorax Thyrsoideus (Muraenidae) In Captivity, Kar-Hoe Loh, Hong-Ming Chen
Pre-Spawning Snout-Gripping Behaviors Of Gymnothorax Pictus And Gymnothorax Thyrsoideus (Muraenidae) In Captivity, Kar-Hoe Loh, Hong-Ming Chen
Journal of Marine Science and Technology–Taiwan
The main focus of this study has been on the distinctive prespawning snout-gripping behaviors and mate choice of two moray species (Gymnothorax pictus and G. thyrsoideus). The behavior of snout-gripping means that the male grips the female’s snout with its jaws. It is the most distinctive behavior to confirm the success of mating pair formation naturally and was rarely described on moray eels or other coral reef fishes. The reproductive behaviors of the two moray species were also first observed and photographed in the laboratory aquaria. Over 22 reproductive events including 9 spawning events by 28 adult individuals of G. …
Individual And Combined Effects Of Herbicide Tribenuron-Methyl And Fungicide Tebuconazole On Soil Earthworm Eisenia Fetida, Jiqiang Chen, Muhammad Saleem, Caixia Wang, Wenxing Liang, Qingming Zhang
Individual And Combined Effects Of Herbicide Tribenuron-Methyl And Fungicide Tebuconazole On Soil Earthworm Eisenia Fetida, Jiqiang Chen, Muhammad Saleem, Caixia Wang, Wenxing Liang, Qingming Zhang
Plant and Soil Sciences Faculty Publications
Earthworms are soil engineers that alter the soil bio-physical properties to favor plant growth whereas pesticides represent a significant threat to their abundance and soil health. Thus, we investigated the toxic effects of tribenuron-methyl (TBM) and tebuconazole (TEB) on the soil earthworm, Eisenia fetida. The TBM demonstrated low toxicity to E. fetida in the contact filter paper and artificial soil tests, with median lethal concentrations (LC50) of 135.6 μg cm−2 at 48 h and 511 mg kg−1 on day 14, respectively. Similarly, TEB also showed low toxicity to E. fetida in the artificial …
Direct Effects Of Warming Increase Woody Plant Abundance In A Subarctic Wetland, Lindsay G. Carlson, Karen H. Beard, Peter B. Adler
Direct Effects Of Warming Increase Woody Plant Abundance In A Subarctic Wetland, Lindsay G. Carlson, Karen H. Beard, Peter B. Adler
Wildland Resources Faculty Publications
Both the direct effects of warming on a species’ vital rates and indirect effects of warming caused by interactions with neighboring species can influence plant populations. Furthermore, herbivory mediates the effects of warming on plant community composition in many systems. Thus, determining the importance of direct and indirect effects of warming, while considering the role of herbivory, can help predict long-term plant community dynamics. We conducted a field experiment in the coastal wetlands of western Alaska to investigate how warming and herbivory influence the interactions and abundances of two common plant species, a sedge, Carex ramenskii, and a dwarf …
Amphibians And Reptiles Of C. E. Miller Ranch And The Sierra Vieja, Chihuahuan Desert, Texas, Usa, Drew R. Davis, Travis J. Laduc
Amphibians And Reptiles Of C. E. Miller Ranch And The Sierra Vieja, Chihuahuan Desert, Texas, Usa, Drew R. Davis, Travis J. Laduc
School of Earth, Environmental, & Marine Sciences Faculty Publications
We report the occurrence of 50 species of amphibians and reptiles recently collected on C. E. Miller Ranch and the Sierra Vieja in the Chihuahuan Desert of Texas, USA and describe their perceived distribution and abundance across various habitat associations of the region. Our recent surveys follow intense, historic sampling of amphibians and reptiles from this region in 1948. Of the 50 species detected in recent surveys, six were not collected in 1948 and an additional three species documented in 1948 have yet to be detected in a 14-year period of recent surveys. Combining data from both historic and recent …
Unveiling The Enigma Of Refractory Carbon In The Ocean, Nianzhi Jiao, Ruanhong Cai, Qiang Zheng, Kai Tang, Jihua Liu, Fangkue Jiao, Douglas Wallace, Feng Chen, Chao Li, Rudolf Amann, Ronald Benner, Farooq Azam
Unveiling The Enigma Of Refractory Carbon In The Ocean, Nianzhi Jiao, Ruanhong Cai, Qiang Zheng, Kai Tang, Jihua Liu, Fangkue Jiao, Douglas Wallace, Feng Chen, Chao Li, Rudolf Amann, Ronald Benner, Farooq Azam
Faculty Publications
No abstract provided.
Global Seawater Redox Trends During The Late Devonian Mass Extinction Detected Using U Isotopes Of Marine Carbonates, David Allen White
Global Seawater Redox Trends During The Late Devonian Mass Extinction Detected Using U Isotopes Of Marine Carbonates, David Allen White
Earth and Planetary Sciences ETDs
The Late Devonian extinction ranks as one of the ‘big five’ Phanerozoic extinctions affecting up to 80% of marine species and occurred during five distinct pulses spanning /or widespread marine anoxia. We test the marine anoxia hypothesis by analyzing uranium isotopes (δ238U) across a ~7 My interval of well-dated Upper Devonian marine carbonates from the Devil’s Gate Limestone in Nevada, USA.
The measured δ238U curve shows no co-variation with local anoxic facies, water-depth dependent facies changes, redox-sensitive metals, TOC, or diagnostic elemental ratios indicating the δ238U curve was not controlled by local depositional or …
Effects Of Elevated Co2, Increased Nitrogen Deposition, And Plant Diversity On Aboveground Litter And Root Decomposition, Xiaoan Zuo, Johannes Knops
Effects Of Elevated Co2, Increased Nitrogen Deposition, And Plant Diversity On Aboveground Litter And Root Decomposition, Xiaoan Zuo, Johannes Knops
School of Biological Sciences: Faculty Publications
Global change-induced litter decomposition strongly affects the carbon (C) and nitrogen (N) dynamics in grassland ecosystems. However, few studies show the interactive effects of global change factors on litter and root decomposition. We conducted a four-year grassland field experiment to examine the quality and decomposition of litter and root in a three-factorial experiment with elevated CO2, increased N deposition, and plant species richness. We found that elevated CO2 decreased the litter N content and root lignin content. N addition increased the root N content and decreased the litter lignin content. Increasing plant richness decreased the N and …
Monthly Paleostreamflow Reconstruction From Annual Tree-Ring Chronologies, James H. Stagge, David E. Rosenberg, R. J. Derose, Tammy M. Rittenour
Monthly Paleostreamflow Reconstruction From Annual Tree-Ring Chronologies, James H. Stagge, David E. Rosenberg, R. J. Derose, Tammy M. Rittenour
Publications
Paleoclimate reconstructions are increasingly used to characterize annual climate variability prior to the instrumental record, to improve estimates of climate extremes, and to provide a baseline for climate-change projections. To date, paleoclimate records have seen limited engineering use to estimate hydrologic risks because water systems models and managers usually require streamflow input at the monthly scale. This study explores the hypothesis that monthly streamflows can be adequately modeled by statistically decomposing annual flow reconstructions. To test this hypothesis, a multiple linear regression model for monthly streamflow reconstruction is presented that expands the set of predictors to include annual streamflow reconstructions, …
Warming Deferentially Altered Multidimensional Soil Legacy Induced By Past Land Use History, Weiling Dong, Alin Song, Xueduan Liu, Bing Yu, Boren Wang, Yuqiu Lu, Yanling Li, Huaqun Yin, Jianwei Li, Fenliang Fan
Warming Deferentially Altered Multidimensional Soil Legacy Induced By Past Land Use History, Weiling Dong, Alin Song, Xueduan Liu, Bing Yu, Boren Wang, Yuqiu Lu, Yanling Li, Huaqun Yin, Jianwei Li, Fenliang Fan
Agricultural and Environmental Sciences Faculty Research
The legacy effects of previous land use and climate history may affect current soil function. However, the manner in which these legacy effects of land use are modulated by the subsequent climate remains unclear. For this reason, we investigated how the legacies of soil multiple functions left by conversion of grassland to agricultural management were mediated by climate warming with a reciprocal transplant approach. The overall legacy was further separated into the contributions by changes in the abiotic properties of the soil (abiotic process) and microbial community (biotic process). We here hypothesized that warming may mediate the legacy effects of …
Cover Crops And Fertilization Alter Nitrogen Loss In Organic And Conventional Conservation Agriculture Systems, Rebecca E. Shelton, Krista L. Jacobsen, Rebecca L. Mcculley
Cover Crops And Fertilization Alter Nitrogen Loss In Organic And Conventional Conservation Agriculture Systems, Rebecca E. Shelton, Krista L. Jacobsen, Rebecca L. Mcculley
Horticulture Faculty Publications
Agroecosystem nitrogen (N) loss produces greenhouse gases, induces eutrophication, and is costly for farmers; therefore, conservation agricultural management practices aimed at reducing N loss are increasingly adopted. However, the ecosystem consequences of these practices have not been well-studied. We quantified N loss via leaching, NH3 volatilization, N2O emissions, and N retention in plant and soil pools of corn conservation agroecosystems in Kentucky, USA. Three systems were evaluated: (1) an unfertilized, organic system with cover crops hairy vetch (Vicia villosa), winter wheat (Triticum aestivum), or a mix of the two (bi-culture); (2) an organic …
Community-Level Plant–Soil Feedbacks Explain Landscape Distribution Of Native And Non-Native Plants, Andrew Kulmatiski
Community-Level Plant–Soil Feedbacks Explain Landscape Distribution Of Native And Non-Native Plants, Andrew Kulmatiski
Wildland Resources Faculty Publications
Plant–soil feedbacks (PSFs) have gained attention for their potential role in explaining plant growth and invasion. While promising, most PSF research has measured plant monoculture growth on different soils in short-term, greenhouse experiments. Here, five soil types were conditioned by growing one native species, three non-native species, or a mixed plant community in different plots in a common-garden experiment. After 4 years, plants were removed and one native and one non-native plant community were planted into replicate plots of each soil type. After three additional years, the percentage cover of each of the three target species in each community was …