Open Access. Powered by Scholars. Published by Universities.®
Other Oceanography and Atmospheric Sciences and Meteorology Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Institution
- Keyword
-
- Ammonia (1)
- Basal resources (1)
- CDOM (1)
- CO2 fertilization (1)
- Carbon starvation (1)
-
- Chromophoric dissolved organic matter (1)
- Climate change (1)
- Drought (1)
- ESA Centennial Paper (1)
- Extreme events (1)
- Fish community structure (1)
- Forest die-off (1)
- Forests (1)
- Formaldehyde (1)
- Hydraulic failure (1)
- Insect pests (1)
- Kelp (1)
- Lakes (1)
- Marine Environment (1)
- Nutrients (1)
- O-Phthaldialdehyde (1)
- Pathogens (1)
- Phytoplankton (1)
- Remote sensing (1)
- Seagrass (1)
- Stable carbon and nitrogen isotopes (1)
- Sulfite (1)
- Surf zone waters (1)
- Tree mortality (1)
- Trophic status (1)
- Publication
- Publication Type
Articles 1 - 5 of 5
Full-Text Articles in Other Oceanography and Atmospheric Sciences and Meteorology
The Development Of A Fluorescence-Based Reverse Flow Injection Analysis (Rfia) Method For Quantifying Ammonium At Nanomolar Concentrations In Oligotrophic Seawater, William Abbott
USF Tampa Graduate Theses and Dissertations
The goal of this thesis was to adopt a reverse flow injection analysis (rFIA) technique to the fluorometric analysis of the reaction o-phthaldialdehyde (OPA) with ammonium, allowing accurate measurements of ammonium concentrations lower than the detection limit of the widely used indophenol blue (IPB) colorimetric method while accounting for the background fluorescence of seawater. Ammonium is considered an essential nutrient for primary productivity, especially in the nutrient depleted surface ocean where as the most reduced form of dissolved inorganic nitrogen, it is readily assimilated via metabolic pathways. Challenges in the quantification of ammonium require more sensitive analytical techniques for …
Temporal Variation In Optical Properties Of Chromophoric Dissolved Organic Matter (Cdom) In Southern California Coastal Waters With Nearshore Kelp And Seagrass, Catherine D. Clark, Warren J. De Bruyn, Paige Aiona
Temporal Variation In Optical Properties Of Chromophoric Dissolved Organic Matter (Cdom) In Southern California Coastal Waters With Nearshore Kelp And Seagrass, Catherine D. Clark, Warren J. De Bruyn, Paige Aiona
Biology, Chemistry, and Environmental Sciences Faculty Articles and Research
Optical properties of chromophoric dissolved organic matter (CDOM) were measured in surf zone waters in diurnal field studies at a Southern California beach with nearshore kelp and seagrass beds and intertidal plant wrack. Absorption coefficients (aCDOM(300 nm)) ranged from 0.35 m21 to 3.7 m21 with short-term variability<1 h, increases at ebb and flood tides and higher values (6 m21) during an offshore storm event. Spectral slopes (S) ranged from 0.0028 nm21 to 0.017 nm21, with higher values after the storm; S was generally inversely correlated with aCDOM(300 nm). 3-D excitation–emission matrix spectra (EEMs) for samples with lower S values had humic-type peaks associated with terrestrial material (A, C), marine microbial material (M) and protein peaks, characteristic of freshly produced organic material. Samples with high S values had no or reduced protein peaks, consistent with aged material. Fluorescent indexes (f450/f500 >2.5, BIX>1.1) were consistent with microbial aquatic sources. Leachates of senescent kelp and seagrass had protein and humic-type EEM peaks. After solar simulator irradiation (4 h), protein peaks rapidly photochemically degraded, humic-type peak C increased in intensity and peak M disappeared. Optical characteristics of kelp leachates were most similar to field samples, …
Exploration Of Spatial And Temporal Changes In Trophic Status Of Lakes In The Northern Temporal Forest Biome Using Remote Sensing, Aleksey Paltsev
Exploration Of Spatial And Temporal Changes In Trophic Status Of Lakes In The Northern Temporal Forest Biome Using Remote Sensing, Aleksey Paltsev
Electronic Thesis and Dissertation Repository
There is a critical need for detailed surveys of lakes covering large spatial (>100 km2) and temporal scales (decades) to determine if there is an increase in the magnitude and frequency of phytoplankton blooms. Remote sensing was used to: (1) develop a regression model that relates chlorophyll a (chl-a) as a proxy of lake phytoplankton biomass to Landsat TM and ETM+ optical reflectance (r2=0.85, p
On Underestimation Of Global Vulnerability To Tree Mortality And Forest Die-Off From Hotter Drought In The Anthropocene, Craig D. Allen, David D. Breshears, Nate G. Mcdowell
On Underestimation Of Global Vulnerability To Tree Mortality And Forest Die-Off From Hotter Drought In The Anthropocene, Craig D. Allen, David D. Breshears, Nate G. Mcdowell
United States Geological Survey: Staff Publications
Patterns, mechanisms, projections, and consequences of tree mortality and associated broadscale forest die-off due to drought accompanied by warmer temperatures—‘‘hotter drought’’, an emerging characteristic of the Anthropocene—are the focus of rapidly expanding literature. Despite recent observational, experimental, and modeling studies suggesting increased vulnerability of trees to hotter drought and associated pests and pathogens, substantial debate remains among research, management and policy-making communities regarding future tree mortality risks. We summarize key mortalityrelevant findings, differentiating between those implying lesser versus greater levels of vulnerability. Evidence suggesting lesser vulnerability includes forest benefits of elevated [CO2] and increased water-use efficiency; observed and modeled increases …
Comparison Of Isotope-Based Biomass Pathways With Groundfish Community Structure In The Eastern Gulf Of Mexico, Sheri Ann Huelster
Comparison Of Isotope-Based Biomass Pathways With Groundfish Community Structure In The Eastern Gulf Of Mexico, Sheri Ann Huelster
USF Tampa Graduate Theses and Dissertations
This study compared traditional community analysis with stable-isotope trophic analysis to define process-based trophic elements of community structure in the eastern Gulf of Mexico, and developed a predictive capability regarding changes to fish community structure that would be expected from increasing eutrophication. Specifically, it used an existing trawl survey program (SEAMAP) to compare invertebrate herbivore (sponge and sea urchin) isotopes with groundfish isotopes, and then compared the resulting spatial patterns with spatial variation in community structure, as identified by cluster analysis. The comparison was applied to seven NMFS survey zones that extended offshore from the Caloosahatchee River, FL northwest to …