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2012

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Articles 31 - 60 of 156

Full-Text Articles in Other Environmental Sciences

Comparative Transcriptome Analysis Of Two Olive Cultivars In Response To Nacl-Stress, Christos Bazakos, Maria E. Manioudaki, Ioannis Therios, Demetrios Voyiatzis, Dimitris Kafetzopoulos, Tala Awada, Panagiotis Kalaitzis Aug 2012

Comparative Transcriptome Analysis Of Two Olive Cultivars In Response To Nacl-Stress, Christos Bazakos, Maria E. Manioudaki, Ioannis Therios, Demetrios Voyiatzis, Dimitris Kafetzopoulos, Tala Awada, Panagiotis Kalaitzis

School of Natural Resources: Faculty Publications

Background: Olive (Olea europaea L.) cultivation is rapidly expanding and low quality saline water is often used for irrigation. The molecular basis of salt tolerance in olive, though, has not yet been investigated at a system level. In this study a comparative transcriptomics approach was used as a tool to unravel gene regulatory networks underlying salinity response in olive trees by simulating as much as possible olive growing conditions in the field. Specifically, we investigated the genotype-dependent differences in the transcriptome response of two olive cultivars, a salt-tolerant and a salt-sensitive one.

Methodology/Principal Findings: A 135-day long …


Flow, Nutrients, And Light Availability Influence Neotropical Epilithon Biomass And Stoichiometry, Tyler J. Kohler, Thomas N. Heatherly Ii, Rana W. El-Sabaawi, Eugenia Zandona, Michael C. Marshall, Alexander S. Flecker, Catherine M. Pringle, David N. Reznick, Steven A. Thomas Aug 2012

Flow, Nutrients, And Light Availability Influence Neotropical Epilithon Biomass And Stoichiometry, Tyler J. Kohler, Thomas N. Heatherly Ii, Rana W. El-Sabaawi, Eugenia Zandona, Michael C. Marshall, Alexander S. Flecker, Catherine M. Pringle, David N. Reznick, Steven A. Thomas

School of Natural Resources: Faculty Publications

Light, nutrient availability, and flow are strong factors controlling the elemental composition and biomass of epilithon in temperate stream ecosystems. However, comparatively little is known about these relationships in tropical streams. We investigated how gradients of light and nutrient availability, seasonality, and habitat influenced epilithon biomass, chlorophyll a, and nutrient ratios in montane streams of Trinidad, West Indies. We sampled 4 focal tributaries of a single river, 2 of which had canopies experimentally thinned, every other month over a 2-y period to observe temporal dynamics and light effects on epilithon. We also sampled 18 sites across Trinidad’s Northern Range Mountains …


U.S. Drought Monitor, August 28, 2012, Brian Fuchs Aug 2012

U.S. Drought Monitor, August 28, 2012, Brian Fuchs

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for August 28, 2012 (8/28/12) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle.


U.S. Drought Monitor, August 21, 2012, Michael J. Brewer, Liz Love-Brotak Aug 2012

U.S. Drought Monitor, August 21, 2012, Michael J. Brewer, Liz Love-Brotak

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for August 21, 2012 (8/21/12) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle.


U.S. Drought Monitor, August 14, 2012, Michael J. Brewer, Liz Love-Brotak Aug 2012

U.S. Drought Monitor, August 14, 2012, Michael J. Brewer, Liz Love-Brotak

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for August 14, 2012 (8/14/12) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle.


U.S. Drought Monitor, August 7, 2012, Mark D. Svoboda Aug 2012

U.S. Drought Monitor, August 7, 2012, Mark D. Svoboda

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for August 7, 2012 (8/7/2012) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle.


Comparing Newly Built Wetlands In The Atchafalaya Bay, Louisiana And Sacramento-San Joaquin Delta, California, Lindsay L. Dunaj Aug 2012

Comparing Newly Built Wetlands In The Atchafalaya Bay, Louisiana And Sacramento-San Joaquin Delta, California, Lindsay L. Dunaj

LSU New Orleans Theses and Dissertations

This research investigated patterns in elevation change in newly built wetlands in the Atchafalaya delta, and newly restored wetlands in the Sacramento-San Joaquin River delta. RSETs were used to measure small changes in elevation, and soil cores were processed to examine mineral and organic contributions.

Elevation change was highly variable, responding to influences from water level, river discharge, storms and vegetation. Mineral matter consistently added more to the marsh soil through volumetric and gravimetric contributions. Organic contributions were not significantly different across sites, suggesting the type of emergent vegetation at a site may not be the most important factor.

Sites …


U.S. Drought Monitor, July 31, 2012, Mark D. Svoboda Jul 2012

U.S. Drought Monitor, July 31, 2012, Mark D. Svoboda

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for July 31, 2012 (7/31/12) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle.


U.S. Drought Monitor, July 10, 2012 Jul 2012

U.S. Drought Monitor, July 10, 2012

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for July 10, 2012 (7/10/12) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans.


Denitrification By Sulfur-Oxidizing Bacteria In A Eutrophic Lake, Amy J. Burgin, Stephen K. Hamilton, Stuart E. Jones, Jay T. Lennon Jul 2012

Denitrification By Sulfur-Oxidizing Bacteria In A Eutrophic Lake, Amy J. Burgin, Stephen K. Hamilton, Stuart E. Jones, Jay T. Lennon

School of Natural Resources: Faculty Publications

Understanding the mechanistic controls of microbial denitrification is of central importance to both environmental microbiology and ecosystem ecology. Loss of nitrate (NO3 −) is often attributed to carbon-driven (heterotrophic) denitrification. However, denitrification can also be coupled to sulfur (S) oxidation by chemolithoautotrophic bacteria. In the present study, we used an in situ stable isotope (15NO3 −) tracer addition in combination with molecular approaches to understand the contribution of sulfur-oxidizing bacteria to the reduction of NO3 − in a eutrophic lake. Samples were incubated across a total dissolved sulfide (H2S) gradient (2 to …


Solar Light Bulb, David G. Guzman, Virgilio Gonzalez Jul 2012

Solar Light Bulb, David G. Guzman, Virgilio Gonzalez

COURI Symposium Abstracts, Summer 2012

The Solar Lighting project is a work driven towards building a low-cost and environmental-friendly solar bulb and to understanding the science behind its behavior. A solar light bulb refers to a device capable of absorbing and transferring solar energy to light up an enclosed area. By using the physical properties of fluids and light is possible to manipulate solar light waves to illuminate an enclosed structure. Moreover, this project attempts to utilize recycled materials that reduce the cost of such device, helping not only the planet but also the costumer’s pocket. The ultimate goal for this project is to scientifically …


U.S. Drought Monitor, July 3, 2012 Jul 2012

U.S. Drought Monitor, July 3, 2012

United States Agricultural Commodities in Drought Archive

Drought map of U.S. for July 3, 2012 (7/3/12) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans.


Droughtscape, Summer 2012, National Drought Mitigation Center Jul 2012

Droughtscape, Summer 2012, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Contents

Director’s report 1

Drought expanse 1

Upcoming ranch workshops. 3

Drought outlook and review 4

Spring impacts summary 6

Hawaii impact workshops 9

Remote sensing of drought. 10

China workshop . 12


Impacts Of An Invasive Snail (Tarebia Granifera) On Nutrient Cycling In Tropical Streams: The Role Of Riparian Deforestation In Trinidad, West Indies, Jennifer M. Moslemi, Sunny B. Snider, Keeley Macneill, James F. Gilliam, Alexander S. Flecker Jun 2012

Impacts Of An Invasive Snail (Tarebia Granifera) On Nutrient Cycling In Tropical Streams: The Role Of Riparian Deforestation In Trinidad, West Indies, Jennifer M. Moslemi, Sunny B. Snider, Keeley Macneill, James F. Gilliam, Alexander S. Flecker

School of Natural Resources: Faculty Publications

Non-native species and habitat degradation are two major catalysts of environmental change and often occur simultaneously. In freshwater systems, degradation of adjacent terrestrial vegetation may facilitate introduced species by altering resource availability. Here we examine how the presence of intact riparian cover influences the impact of an invasive herbivorous snail, Tarebia granifera, on nitrogen (N) cycling in aquatic systems on the island of Trinidad. We quantified snail biomass, growth, and N excretion in locations where riparian vegetation was present or removed to determine how snail demographics and excretion were related to the condition of the riparian zone. In three …


The Effects Of Biochar Age And Concentration On Soil Retention Of Phosphorus And Infiltration Rate, Emilie Schneider Jun 2012

The Effects Of Biochar Age And Concentration On Soil Retention Of Phosphorus And Infiltration Rate, Emilie Schneider

Natural Resources Management and Environmental Sciences

Changes in land use and land management practices are regarded as one of the main factors in altering the hydrogeological system, causing changes in runoff, surface supply yields, and the quality of receiving water (Tong and Chen, 2002). Phosphorus is a significant contributor to accelerated eutrophication of fresh water and is largely sourced from agricultural runoff (Sharpley et al., 1994). The dominant processes controlling solution composition in agricultural soils are primarily ‘chemical’ for P (i.e. adsorption/desorption and dissolution/precipitation) (Edwards and Withers, 1998). Biochar has chemical characteristics that have the potential to adsorb P or influence precipitation of P insoluble pools …


The Effects Of Utility Pole Placement And Characteristics On Pentachlorophenol Concentrations Entering Underground Injection Control (Uic) Devices: City Of Gresham, Oregon, Katie Bohnren Jun 2012

The Effects Of Utility Pole Placement And Characteristics On Pentachlorophenol Concentrations Entering Underground Injection Control (Uic) Devices: City Of Gresham, Oregon, Katie Bohnren

Environmental Science and Management Professional Master's Project Reports

Urbanization is causing increased amounts of stormwater runoff, while simultaneously decreasing the amount of pervious surface area for infiltration. Multiple priority pollutants have been identified in urban stormwater, including pentachlorophenol (PCP). PCP is often found in stormwater samples exceeding the Safe Drinking Water Act limit of 1μg/L and can cause human health issues with exposure over time. Treated wood utility poles are the major source of PCP in urban stormwater. With the use of underground injection control (UIC) devices as an alternative method to treat and dispose of stormwater, the potential exists for groundwater contamination of PCP. The City of …


Citizen Action, Power Relations And Wetland Management In The Tampa Bay Urban Socio-Ecosystem, Cornelius Owusu Adjei May 2012

Citizen Action, Power Relations And Wetland Management In The Tampa Bay Urban Socio-Ecosystem, Cornelius Owusu Adjei

USF Tampa Graduate Theses and Dissertations

Wetlands are vital ecosystems that provide ecological, economic and social benefits to societies. In the Tampa Bay region in West Central Florida, a growing population has put immense pressure on wetlands. The situation has not gone unnoticed in the public domain with concerns raised about the need to formulate policies that would protect them. However, it has been difficult to ascertain the level of citizen involvement in the decision making process.

This study aimed at investigating whether the perceptions and concerns of citizens drove them to influence local water policy. Questionnaires were used to collect data from residents living in …


Sedimentology And Geochronology Of Holocene Paleochannel Features In The Lower Ohio River Valley, Indiana, Kathryn G. De Rego, C. Russell Stafford, Mark Cantin May 2012

Sedimentology And Geochronology Of Holocene Paleochannel Features In The Lower Ohio River Valley, Indiana, Kathryn G. De Rego, C. Russell Stafford, Mark Cantin

Symposium 2012

Rivers condition human settlement strategy by determining both the location of aquatic resources and the stability of the landscape. Therefore, understanding where the river was and how quickly it migrated in the past aids in predicting buried site potential. This study investigates the sedimentology and geochronology of paleochannel deposits along the Lower Ohio River floodplain. A series of low, wide swales are prominent features in a series of bottoms in a ~40 km section of the river valley downstream from the Falls of the Ohio. Previous studies in Knob Creek Bottom indicate that one of these paleochannel swales was active …


Analysis Of Biodiesel Quality Using Reversed Phase High-Performance Liquid Chromatography, Kellyann M. Murphy May 2012

Analysis Of Biodiesel Quality Using Reversed Phase High-Performance Liquid Chromatography, Kellyann M. Murphy

Pomona Senior Theses

The alternative fuel biodiesel is produced from the transesterification of vegetable oils or animal fat to fatty acid methyl esters. Pomona has a reactor on campus that can be used to run this reaction and produce biodiesel. The use of biodiesel has been found to lower air pollutant and greenhouse gas emissions, but can be potentially harmful to the engines if it contains impurities. This paper proposes a method using high-performance liquid chromatography to test the quality of biodiesel. This method utilizes instrumentation and materials that are available in Pomona College's Chemistry Department, requires very little sample preparation, and is …


Bikeurious: A Transportation Reorientation, Aerienne Russell May 2012

Bikeurious: A Transportation Reorientation, Aerienne Russell

Pomona Senior Theses

Since a young age, I have been interested in bicycling as a form of fun and fanciful recreation, but it wasn’t until the summer of 2011 that a serious shift occurred in my understanding of the bike as more than a mere machine. A spontaneous 700-mile journey redefined my relationship with travel, transcended my notions of transportation, and enabled me to better mediate myself within my environment. In writing about these experiences, I hope to offer some insight into how American culture currently frames transportation and how I hope the construction of a bike positive culture can instill social, environmental, …


The Full Cost Of Renewables: Managing Wind Integration Costs In California, William Savage May 2012

The Full Cost Of Renewables: Managing Wind Integration Costs In California, William Savage

Pomona Senior Theses

Wind power will be an important component of California's aggressive strategies to meet its greenhouse gas reduction targets by the year 2020. However, the costs of integrating wind power's variable and uncertain output are often ignored. I argue that California must take prudent action to understand, minimize, and allocate wind integration costs. A review of numerous studies suggests that for wind penetration levels below 20%, integration costs should remain modest. However, costs are heavily dependent on market structure, and I suggest numerous ways that California can optimize its market design to manage wind integration costs.


San Antonio High School Food Justice Program: A Handbook And Evaluation Of Edible Education, Katherine B. Tenneson May 2012

San Antonio High School Food Justice Program: A Handbook And Evaluation Of Edible Education, Katherine B. Tenneson

Pitzer Senior Theses

This senior environmental studies thesis explains and analyzes edible education through a food and gardening program at a continuation high school in Claremont, California. The first chapter situates the program-specific analysis by providing background information of the edible education movement, a history of the Edible Schoolyard in Berkeley, California, and an explanation of why food is a powerful teaching tool. The second chapter delineates the program by describing all of its components and compiling essential resources and teaching documents. The third chapter is based on interviews with 9 of 12 involved students and 7 teachers, and thoroughly explains the outcomes …


The Communicator, Volume 8, Issue 1, May 2012 May 2012

The Communicator, Volume 8, Issue 1, May 2012

The Communicator: News from the Nebraska Cooperative Fish and Wildlife Research Unit

Research Highlight: Assessing the Effects of Habitat Incentives and Public Access Programs on Pheasant Populations

Honors and Awards: Jason DeBoer, Kent Fricke, Shana Sundstrom, Karie Decker, Dan Uden, Josiah Dallmann, Victoria Simonsen, Valerie Egger, Michelle Hellman, and Bethany Teeters

Moving On: Ryan Stutzman, Chris Jorgensen, Kody Unstad

Teaching: Joseph (TJ) Fontaine and Kevin Pope

Outreach Activities: Karie Decker, Carla Bobier, Chris Jorgensen, Caroline Jezierski

Training: Creel Survey Workshop

Invasive Species Update: Nebraska LB 391

Publications: Jason DeBoer, Dustin Martin, Kevin Pope, Shana Sundstrom, Craig Allen

Announcements: Stella Elizabeth Spirk, Milo Leroy Bobier

Conferences/Meetings/Workshops:
Midwest Fish and Wildlife Conference held in …


Sediment Removal From The San Gabriel Mountains, Mary C. Ferguson May 2012

Sediment Removal From The San Gabriel Mountains, Mary C. Ferguson

Pitzer Senior Theses

The issue of sediment removal from the San Gabriel Mountains has been a complex issue that has created problems with beach replenishment, habitat destruction and the need to spend millions of dollars at regular intervals to avoid safety hazards. Most recently 11 acres of riparian habitat, including 179 oaks and 70 sycamores, were removed for sediment placement. Other sites including Hahamongna Watershed Park and La Tuna Canyon also face a similar fate. This thesis questions: How did we get to this point of destroying habitat to dump sediment which is viewed as waste product? What are the barriers for creating …


Assessing Population-Level Effects Of Zinc Exposure To Brown Trout (Salmo Trutta) In The Arkansas River At Leadville, Colorado, John Toll, Kristina Garber, David Deforest, William Brattin Apr 2012

Assessing Population-Level Effects Of Zinc Exposure To Brown Trout (Salmo Trutta) In The Arkansas River At Leadville, Colorado, John Toll, Kristina Garber, David Deforest, William Brattin

United States Environmental Protection Agency: Publications

We assessed population-level risk to upper Arkansas River brown trout (Salmo trutta L.) due to juvenile exposure to Zn. During spring, individuals in the sensitive young-of-the-year life stage are exposed to elevated Zn concentrations from acid mine drainage. We built and used a simple life-history population model for the risk assessment, with survival and fecundity parameter values drawn from published data on brown trout populations located in the United States and Europe. From experimental data, we derived a toxicity model to predict mortality in brown trout fry after chronic exposure to Zn. We tested sensitivity of risk estimates to …


Droughtscape, Spring 2012, National Drought Mitigation Center Apr 2012

Droughtscape, Spring 2012, National Drought Mitigation Center

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Contents

Director’s report.

Climate Masters 1

Ranch plan workshop . 3

Winter climate summary 4

Winter impacts summary . 6

Zhao research.

Getachew research 0

Other international news

Wardlow move 13

IPCC disaster report .


Water And Energy Balance Response Of A Riparian Wetland To The Removal Of Phragmites Australis, Phillip Mykleby Apr 2012

Water And Energy Balance Response Of A Riparian Wetland To The Removal Of Phragmites Australis, Phillip Mykleby

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Vegetation and climate both play integral roles in water availability, particularly for arid to semi-arid regions. Changes in these variables can lead to extreme shortages in water for regions that rely on water for crop irrigation (i.e., the Great Plains). The objective of this study is to evaluate the impacts of vegetation on water availability in the Republican River basin in central Nebraska. Decreases in streamflow have been observed in the river basin for many years and, as a result, an invasive riparian plant species (Phragmites australis) is being removed in an effort to reduce evapotranspiration and reclaim …


Feeding Habitats Of The Gulf Sturgeon, Acipenser Oxyrinchus Desotoi, In The Suwannee And Yellow Rivers, Florida, As Identified By Multiple Stable Isotope Analyses, Kenneth J. Sulak, J. J. Berg, M. Randall Mar 2012

Feeding Habitats Of The Gulf Sturgeon, Acipenser Oxyrinchus Desotoi, In The Suwannee And Yellow Rivers, Florida, As Identified By Multiple Stable Isotope Analyses, Kenneth J. Sulak, J. J. Berg, M. Randall

United States Geological Survey: Staff Publications

Stable 13C, 15N, and 34S isotopes were analyzed to define the feeding habitats of Acipenser oxyrinchus desotoi in the Suwannee and Yellow River populations. For the majority (93.9%) of Suwannee sub adults and adults, 13C and 34S signatures indicate use of nearshore marine waters as primary winter feeding habitat, probably due to the limiting size of the Suwannee Sound estuary. In the Yellow River population, 13C isotope signatures indicate that adults remain primarily within Pensacola Bay estuary to feed in winter, rather than immigrating to the open Gulf of Mexico. A minor Suwannee River subset (6% of …


Heterogeneous Detection Probabilities For Imperiled Missouri River Fishes: Implications For Large-River Monitoring Programs, Joshua T. Schloesser, Craig P. Paukert, Wyatt J. Doyle, Tracy D. Hill, Kirk D. Steffensen, Vince H. Travnichek Mar 2012

Heterogeneous Detection Probabilities For Imperiled Missouri River Fishes: Implications For Large-River Monitoring Programs, Joshua T. Schloesser, Craig P. Paukert, Wyatt J. Doyle, Tracy D. Hill, Kirk D. Steffensen, Vince H. Travnichek

United States Geological Survey: Staff Publications

Occupancy modeling was used to determine (1) if detection probabilities (p) for 7 regionally imperiled Missouri River fishes (Scaphirhynchus albus, Scaphirhynchus platorynchus, Cycleptus elongatus, Sander canadensis, Macrhybopsis aestivalis, Macrhybopsis gelida, and Macrhybopsis meeki) differed among gear types (i.e. stationary gill nets, drifted trammel nets, and otter trawls), and (2) how detection probabilities were affected by habitat (i.e. pool, bar, and open water), longitudinal position (five 189 to 367 rkm long segments), sampling year (2003 to 2006), and season (July 1 to October 30 and October 31 to June 30). Adult, large-bodied fishes were …


Habitat And Prey Availability Attributes Associated With Juvenile And Early Adult Pallid Sturgeon Occurrence In The Missouri River, Usa, Bryan D. Spindler, Steven R. Chipps, Robert A. Klumb, Brian D. S. Graeb, Michael C. Wimberly Mar 2012

Habitat And Prey Availability Attributes Associated With Juvenile And Early Adult Pallid Sturgeon Occurrence In The Missouri River, Usa, Bryan D. Spindler, Steven R. Chipps, Robert A. Klumb, Brian D. S. Graeb, Michael C. Wimberly

United States Geological Survey: Staff Publications

The pallid sturgeon Scaphirhynchus albus is a federally endangered species native to the Missouri and lower Mississippi Rivers, USA. As part of recovery efforts, over 360 000 pallid sturgeon have been stocked into the Missouri River since 1994, and a standardized, long-term monitoring program was initiated in 2003. Understanding the distribution and habitat requirements of juvenile and early adult pallid sturgeon (fork length <720 mm, age <10 yr) is an important goal of the monitoring and recovery programs. In this study, we collected information on habitat characteristics and prey availability from the upper Missouri River along the Nebraska-South Dakota border and compared these attributes between capture (present) and non-capture (absent) locations (N = 59). To evaluate the relative influence of habitat and prey availability on pallid sturgeon occurrence, we examined several candidate models using an informationtheoretic approach. A prey availability model had the most support and included site-specific information on Diptera and Ephemeroptera abundance. A habitat-based model showed that juveniles and early adults were found in relatively deeper water and avoided areas where bottom velocities were greater than 1.2 m s−1. Although not as well supported as the prey-effects model (evidence ratio = 6.4), habitat features also provided a plausible model for predicting occurrence. The models developed here could be used to evaluate pallid sturgeon habitat potential in the Missouri River basin and help guide future monitoring and conservation management of this endangered species.