Physical Sciences and Mathematics Commons^™

Sustainable Fertilizer Management Practices For Container Nursery Production, Saroj Burlakoti

All Graduate Theses and Dissertations, Fall 2023 to Present

Growing nursery plants in containers requires a timely supply of mineral nutrients for optimum growth. However, there is a misconception among growers that the application of higher doses of fertilizers hastens plant growth; instead, it can lead to runoff and leaching loss of nutrients. Reducing fertilizer application while sustaining healthy plants can not only negate environmental consequences but also save fertilizer costs. For example, two ground covers, Lysimachia nummularia (creeping jenny, moneywort) and Vinca minor 'Bowles' (periwinkle), can be grown for three months by applying 6 mg/L of phosphorus (P) as reduction of P to single application of 6 mg/L …

Phosphorus Dynamics In Calcareous Soils Amended With Organic Matter, Logan Banner

All Graduate Reports and Creative Projects, Fall 2023 to Present

Phosphorus (P) is considered immobile in calcareous soils. Organic matter is known to enhance P mobility in these soils. Few studies have considered what role iron oxides might play in P sorption in calcareous soils, especially in the presence of soluble organic matter. This study investigated P sorption dynamics in sand-based, simulated soil systems in the absence or presence of 5 mM carbon (C) as humic acid (HA). Treatments included combinations of dicalcium phosphate dihydrate (DCPD), calcite, and ferrihydrite. Solutions containing 10 mg P L^-1 in a background of 0.01 M CaCl₂were equilibrated with each solid treatment …

Fire And Flow: Assessing The Long-Term Effects Of Wildfires And Impact Of High Flow Events On Phosphorus Concentrations In Mountain Streams, Rachel Watts

All Graduate Theses and Dissertations, Fall 2023 to Present

Climate change has led to significant shifts in the Earth’s weather patterns, often leading to longer, more intense droughts, irregular but extreme storms, and more severe wildfires with longer burn durations. These weather pattern changes have frequently led to shifts in ecosystem dynamics, impacting aspects such as nutrient flux, species diversity, and overall habitat health. Regarding nutrient flux specifically, changes in phosphorus (P) concentrations can negatively impact stream systems as elevated levels can lead to toxic algal blooms, which can cause habitat degradation, loss of usable recreational areas, and large fish kills. A common trigger of these P spikes is …

Getting The Dirt On Phosphorus Pollution In Mountain Lakes: Are Rising Soil Temperatures Contributing To Eutrophication In Mountain Watersheds?, Gordon O. Gianniny

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mountain watersheds provide a critical supply of clean water to millions of people around the world. In recent years, evidence of a concerning trend has emerged in these watersheds: rising phosphorus (P) concentrations. P often acts as the limiting nutrient in mountain lake ecosystems, so increasing P availability in mountain lakes and streams has the potential to drastically increase algal growth in these systems. In extreme cases, increasing mountain lake P concentrations may even cause harmful algal blooms that degrade downstream water quality. While the implications of rising P concentrations in mountain lakes are serious, the cause driving this widespread …

Bear Lake Limnology & Nutrient Limnology, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

No abstract provided.

Is Atmospheric Phosphorus Pollution Altering Global Alpine Lake Stoichiometry?, Janice Brahney, Natalie Mahowald, Daniel S. Ward, Ashley P. Ballantyne, Jason C. Neff

Watershed Sciences Faculty Publications

Anthropogenic activities have significantly altered atmospheric chemistry and changed the global mobility of key macronutrients. Here we show that contemporary global patterns in nitrogen (N) and phosphorus (P) emissions drive large hemispheric variation in precipitation chemistry. These global patterns of nutrient emission and deposition (N:P) are in turn closely reflected in the water chemistry of naturally oligotrophic lakes (r2 = 0.81, p < 0.0001). Observed increases in anthropogenic N deposition play a role in nutrient concentrations (r2 = 0.20, p < 0.05); however, atmospheric deposition of P appears to be major contributor to this pattern (r2 = 0.65, p < 0.0001). Atmospheric simulations indicate a global increase in P deposition by 1.4 times the preindustrial rate largely due to increased dust and biomass burning emissions. Although changes in the mass flux of global P deposition are smaller than for N, the impacts on primary productivity may be greater because, on average, one unit of increased P deposition has 16 times the influence of one unit of N deposition. These stoichiometric considerations, combined with the evidence presented here, suggest that increases in P deposition may be a major driver of alpine Lake trophic status, particularly in the Southern Hemisphere. These results underscore the need for the broader scientific community to consider the impact of atmospheric phosphorus deposition on the water quality of naturally oligotrophic lakes.

Dust Mediated Transfer Of Phosphorus To Alpine Lake Ecosystems Of The Wind River Range, Wyoming, Usa, Janice Brahney, Ashley P. Ballantyne, P. Kociolek, Sarah A. Spaulding, Megan Otu, T. Porwoll, Jason C. Neff

Watershed Sciences Faculty Publications

Alpine lakes receive a large fraction of their nutrients from atmospheric sources and are consequently sensitive to variations in both the amount and chemistry of atmospheric deposition. In this study we explored the spatial changes in lake water chemistry and biology along a gradient of dust deposition in the Wind River Range, Wyoming. Regional differences were explored using the variation in bulk deposition, lake water, sediment, and bedrock geochemistry and catchment characteristics. Dust deposition rates in the Southwestern region averaged 3.34 g m−2 year−1, approximately three times higher than deposition rates in the Northwestern region (average 1.06 g m−2 year−1). …

Nutrient Limitation Of Phytoplankton By Nitrogen And Phosphorus: Erosion Of The Phosphorus Paradigm, Wayne A. Wurtsbaugh, William M. Lewis Iii

Watershed Sciences Faculty Publications

No abstract provided.

Freshwater Responses To Nitrogen And Phosphorus Pollution And A Case Study Of Cutler And Dingle Marsh Wetlands, Wayne A. Wurtsbaugh

Watershed Sciences Faculty Publications

No abstract provided.

The Efficacy Of Plant Residue Degradation Products On Phosphorus, Iron, Iodine, And Fluorine Bioavailability To Plants, Cheryl L. Mackowiak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plant and animal wastes degrade in soils to form relatively stable humified compounds, which form ion complexes that affect the bioavailability of elements in the soil solution. Hydroponic studies with wheat and rice were conducted to characterize the effect of humic acid (HA) on phosphorus (P), iron (Fe), fluorine (F), and iodine (I) bioavailability. Ferrihydrite [Fe(OH)₃] precipitation was greater on root surfaces without HA or synthetic chelates. Oxides such as ferrihydrite strongly adsorb P and provide exchange sites for metals. HA reduced this precipitate and increased P and Fe uptake.

Humic acid had no effect on F toxicity …

1972 Progress Report: Soil As A Factor In Modelling The Phosphorus Cycle In The Desert Ecosystem, J. J. Jurinak, R. A. Griffin

Elusive Documents

The research conducted in 1972 emphasized a nutrient assay of soil from the Curlew Valley site, phosphorus inventory of the vegetation and rabbit droppings, and further chemical characterization of soil phosphorus, which also included determination of the kinetics and energetics of the calcium carbonate-phosphate system.

The Effect Of Chelates On Phosphorus Availability And Mobility, Salah Ahmed Tahoun

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soil-phosphorus relations and plant-phosphorus relations have attracted the interest of many investigators since Liebig introduced his famous theory about the importance of the mineral matters to the plant in 1840. It was soon realized that phosphorus nutrition was a problem not easily solved for two reasons. 1. The added phosphorus fertilizers, soon after soil application are converted by some reactions in the soil to complex compounds far less soluble, consequently less available to the plant. Conclusions about this process led to controversial debates until it was discovered that a general statement covering all soils was impossible since the reactions involved …

Phosphorus Status Of Genola Soils In Utah, Warren E. Bendixen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With increasing pressure on economical production of crops, more fertilizers are being applied to the soil each year to increase crop yields. Economical production of crops with applications of fertilizer requires an evaluation of the essential elements of the various crops so applications of fertilizer will not exceed the law of diminishing returns.

Because varying soil, moisture, and climatic conditions influence the response to added fertilizers, some workers (18, 26, 38) have contended that the only reliable way of determining the fertilization needs of a crop is to conduct a trial on the particular farm. The length of time involved …

The Influence Of Soil Moisture Conditions On The Absorption Of Phosphorus By Plants From Calcareous Soils, T. J. Denman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Phosphorus is one of the major plant nutrients secured from the soil. The object of many investigations has been to discover the nature of the processes by which the soil supplies phosphorus to plants, and to determine the influence of soil factors upon these processes. Although much knowledge has been gained, these processes and the effects of soil factors upon them are still not clearly defined.

One factor which profoundly affects plant growth is the amount and relative availability of soil moisture. The results of some investigations have suggested that this factor may also have considerable influence on the absorption …