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Full-Text Articles in Physical Sciences and Mathematics

Predicting Combined Effects Of Land Use And Climate Change On River And Stream Salinity, John Olson Dec 2018

Predicting Combined Effects Of Land Use And Climate Change On River And Stream Salinity, John Olson

John Olson

Agricultural, industrial and urban development have all contributed to increased salinity in streams and rivers, but the likely effects of future development and climate change are unknown. I developed two empirical models
to estimate how these combined effects might affect salinity by the end of this century (measured as electrical conductivity, EC). The first model predicts natural background from static (e.g. geology and soils) and dynamic
(i.e. climate and vegetation) environmental factors and explained 78% of the variation in EC. I then compared the estimated background EC with current measurements at 2001 sites chosen probabilistically from all conterminous USA streams. …


Hydrological Hazard Assessment For Irrigated Agriculture In The Irwin Focus Area, Russell J. Speed, Adele L. Killen Nov 2018

Hydrological Hazard Assessment For Irrigated Agriculture In The Irwin Focus Area, Russell J. Speed, Adele L. Killen

Resource management technical reports

The Midlands groundwater and land assessment project aimed to identify 2000–3000 hectare precincts suitable to develop intensive irrigated horticulture. The primary focus area was at Irwin, where the Department of Water and Environmental Regulation investigated groundwater resources and the Department of Primary Industries and Regional Development undertook a multi-faceted site assessment. This report describes the hydrological hazards assessment for the Irwin focus area.

The Irwin focus area is located on fertile loam and clay flats associated with the Irwin River. In the east, it encompasses the Irwin River valley floor and the western boundary loops to the south of the …


Analysis Of Temperature And Salinity Effects On Growth And Mortality Of Oysters (Crassostrea Virginica) In Louisiana, Troy Sehlinger Aug 2018

Analysis Of Temperature And Salinity Effects On Growth And Mortality Of Oysters (Crassostrea Virginica) In Louisiana, Troy Sehlinger

University of New Orleans Theses and Dissertations

Salinity (S) and temperature (T) control every facet of the eastern oyster (Crassostrea virginica) life cycle, principally reproduction, development, growth, and mortality. Previous studies conducted in in the Breton Sound (BR) and Barataria (BA) estuaries have reported differences in growth and mortality rates between the basins. In the present study, environmental conditions were synchronized to compare growth and mortality rates between basins at similar combinations of T and S. Results indicate that when T and S are the same (synchronized), seasonal oyster growth and mortality rates differ between BR and BA. Seasonal analyses revealed that as salinities increased …


Presence/Absence And Density Data For Epipelagic Tows Collected During R/V Blazing Seven Cruises Lf2016a And Lf2016b, Northern Gulf Of Mexico From 2016-06-09 To 2016-07-28, Jay R. Rooker, David Wells Jul 2018

Presence/Absence And Density Data For Epipelagic Tows Collected During R/V Blazing Seven Cruises Lf2016a And Lf2016b, Northern Gulf Of Mexico From 2016-06-09 To 2016-07-28, Jay R. Rooker, David Wells

DEEPEND Datasets

This dataset reports presence/absence and density data for epipelagic tows collected in the northern Gulf of Mexico during R/V Blazing Seven cruises LF2016A and LF2016B (2016-06-09 to 2016-07-28). Larval fishes were sampled from 48 stations and cruise data were collected at each site including latitude/longitude, date, time, environmental data (temperature, salinity, dissolved oxygen) and Sargassum dry weight. Larval catch data before and after the oil spill will be compared to improve our understanding of the causes of temporal variability as it relates to the Deep-Water Horizon oil spill (DWHOS). Habitat associations of selected taxa (billfishes, tunas, dolphinfishes, flyingfishes) will be …


Climate And Plant Controls On Soil Organic Matter In Coastal Wetlands, Michael J. Osland, Christopher A. Gabler, James B. Grace, Richard H. Day, Meagan L. Mccoy, Jennie L. Mcleod, Andrew S. From, Nicholas M. Enwright, Laura C. Feher, Camille L. Stagg Jun 2018

Climate And Plant Controls On Soil Organic Matter In Coastal Wetlands, Michael J. Osland, Christopher A. Gabler, James B. Grace, Richard H. Day, Meagan L. Mccoy, Jennie L. Mcleod, Andrew S. From, Nicholas M. Enwright, Laura C. Feher, Camille L. Stagg

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Coastal wetlands are among the most productive and carbon‐rich ecosystems on Earth. Long‐term carbon storage in coastal wetlands occurs primarily belowground as soil organic matter (SOM). In addition to serving as a carbon sink, SOM influences wetland ecosystem structure, function, and stability. To anticipate and mitigate the effects of climate change, there is a need to advance understanding of environmental controls on wetland SOM. Here, we investigated the influence of four soil formation factors: climate, biota, parent materials, and topography. Along the northern Gulf of Mexico, we collected wetland plant and soil data across elevation and zonation gradients within 10 …


Recent Conditions Highlight Regional Differences In Temperature, Salinity And Dissolved Oxygen Between Strait Of Juan De Fuca And Puget Sound Sites Under Anomalous 2014-2017 Climate Patterns, Julia Bos, Christopher Krembs, S. L. Albertson, Mya Keyzers, Allison Brownlee, Carol Maloy Apr 2018

Recent Conditions Highlight Regional Differences In Temperature, Salinity And Dissolved Oxygen Between Strait Of Juan De Fuca And Puget Sound Sites Under Anomalous 2014-2017 Climate Patterns, Julia Bos, Christopher Krembs, S. L. Albertson, Mya Keyzers, Allison Brownlee, Carol Maloy

Salish Sea Ecosystem Conference

Understanding impacts of climate change on Salish Sea water quality is critical yet challenging due to the complexity, strength and diversity of influences on circulation and mixing. Different extreme climate conditions in recent years (2014-2017) include record warm temperatures with reduced snow pack in 2014-2015 followed by a few years of alternating summer droughts with record rainy seasons. These conditions influenced marine water temperature, salinity and dissolved oxygen (DO) throughout the Salish Sea. Analyses reveal distinct differences in these key physical and chemical characteristics between Strait of Juan de Fuca sites and sites within Puget Sound basins. Extremely low DO …


Identifying And Characterizing Salt-Tolerant Alfalfa (Medicago Sativa Subsp Falcata Germplasm, Katelin E. Frerichs, Lan Xu Jan 2018

Identifying And Characterizing Salt-Tolerant Alfalfa (Medicago Sativa Subsp Falcata Germplasm, Katelin E. Frerichs, Lan Xu

Natural Resource Management Faculty Publications

Soil salinity limits plant growth and crop production. More than 20% of cultivated land worldwide is affected by salinity. The situation is becoming more severe due to shifts in precipitation and evaporation patterns and improper irrigation. There is an urgent need to develop salt-tolerant, economically valuable plants to minimize the loss of and to sustain agricultural production. Alfalfa is one of the most extensively cultivated forage crops. Some yellow-flowered alfalfa (Medicago sativa subsp. falcata) have exhibited morphological and physiological drought tolerance. Since soil salinity is associated with physiological drought, it is reasonable to expect that these drought tolerant falcata populations …


A Combined Field, Experimental And Modeling Approach To Understand The Impacts Of Flood Irrigation On Pedogenic Caco3 And Co2 Dynamics In Drylands, Anna Cristina Ortiz Jan 2018

A Combined Field, Experimental And Modeling Approach To Understand The Impacts Of Flood Irrigation On Pedogenic Caco3 And Co2 Dynamics In Drylands, Anna Cristina Ortiz

Open Access Theses & Dissertations

Soil salinization is a global problem affecting 10% of agricultural soils, particularly in irrigated arid-lands. This study investigated salt loading through flood-irrigation, particularly of calcite (CaCO3) salt in the southwest of the United States. To evaluate the impact that flood-irrigation has on CaCO3 buildup and its effect on C-cycling, a natural soil and two agricultural soils were sampled: a pecan orchard and an alfalfa field in the El Paso, TX region. Agricultural soils in this study are flood irrigated by the Rio Grande river and by ground waters in its absence, both of which are oversaturated with calcite.

To trace …