Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons™

Open Access. Powered by Scholars. Published by Universities.®

2016

Carbon

Articles 1 - 10 of 10

Full-Text Articles in Life Sciences

Year-Round Measures Of Planktonic Metabolism Reveal Net Autotrophy In Surface Waters Of A Great Lakes Estuary, Angela L. Defore, Anthony D. Weinke, Morgan M. Lindback, Bopaiah A. Biddanda Sep 2016

Year-Round Measures Of Planktonic Metabolism Reveal Net Autotrophy In Surface Waters Of A Great Lakes Estuary, Angela L. Defore, Anthony D. Weinke, Morgan M. Lindback, Bopaiah A. Biddanda

Funded Articles

During 2009 and 2010, we quantified monthly changes in plankton metabolism and environmental variables in the surface waters of Muskegon Lake, a Great Lakes estuary connected to Lake Michigan. Muskegon Lake’s mean (±SE) annual gross plankton primary production (GPP) and respiration (R) rates were 46 ± 9 and 23 ± 4 mg C l−1 yr−1, respectively. GPP:R ratios of 0.6 to +4.8 with a yearly mean of 2.0 ± 0.3 indicated that the surface water of Muskegon Lake was net autotrophic during all but the winter months under ice cover, when it was in a near carbon balance to slightly …

Go to article

Microbial Extracellular Enzymes In Marine Sediments: Methods Development And Potential Activities In The Baltic Sea Deep Biosphere, Jenna Marie Schmidt Aug 2016

Microbial Extracellular Enzymes In Marine Sediments: Methods Development And Potential Activities In The Baltic Sea Deep Biosphere, Jenna Marie Schmidt

Masters Theses

The deep biosphere is defined as the subsurface ecosystem in which little energy is available to microorganisms and microorganisms can live for thousands of years. Heterotrophic microbes survive in the deep biosphere even though organic matter is limited and highly recalcitrant in nature. Measuring microbial extracellular enzyme activity provides a potential means to evaluate the rate at which microorganisms are performing carbon remineralization in the energy limited sediment beneath the seafloor. Extracellular enzymes breakdown organic compounds so that the nutrients can move inside the cell and be used for energy. This study explored the role extracellular enzymes play in the …

Go to article

The Growth Response Of Two Diatom Species To Atmospheric Dust From The Last Glacial Maximum, Tim M. Conway, Linn J. Hoffmann, Eike Breitbarth, Robert F. Strzepek, Eric W. Wolff Jul 2016

The Growth Response Of Two Diatom Species To Atmospheric Dust From The Last Glacial Maximum, Tim M. Conway, Linn J. Hoffmann, Eike Breitbarth, Robert F. Strzepek, Eric W. Wolff

Marine Science Faculty Publications

Relief of iron (Fe) limitation in the surface Southern Ocean has been suggested as one driver of the regular glacial-interglacial cycles in atmospheric carbon dioxide (CO2). The proposed cause is enhanced deposition of Fe-bearing atmospheric dust to the oceans during glacial intervals, with consequent effects on export production and the carbon cycle. However, understanding the role of enhanced atmospheric Fe supply in biogeochemical cycles is limited by knowledge of the fluxes and 'bioavailability' of atmospheric Fe during glacial intervals. Here, we assess the effect of Fe fertilization by dust, dry-extracted from the Last Glacial Maximum portion of the EPICA Dome …

Go to article

Compost Land Management And Soil Carbon Sequestration, Kylene A. Hohman May 2016

Compost Land Management And Soil Carbon Sequestration, Kylene A. Hohman

Senior Honors Projects, 2010-2019

Extensive fossil fuel burning has released carbon dioxide into the atmosphere. Under proper ecological conditions plants convert atmospheric carbon dioxide into stable soil organic matter, a natural and efficient means of mitigating climate change. In the symbiotic relationship between mycorrhizae and plants, mycorrhizae provide plants with essential nutrients in exchange for carbon sugars leaked from the plants. Mycorrhizae convert carbon sugars to an exudate called glomalin, a protein that assists in developing soil aggregates composed of sand, silt, and clay. These aggregates, called humus, store carbon for hundreds of years under healthy ecological conditions. Compost prompts soil microbes to aerobically …

Go to article

Variation In Stem Mortality Rates Determines Patterns Of Above-Ground Biomass In Amazonian Forests: Implications For Dynamic Global Vegetation Models, Michelle O. Johnson, David R. Galbraith, Manuel Gloor, Hannes De Deurwaerder, Matthieu Guimberteau, Anja Rammig, Kirsten Thonicke, Hans Verbeeck, Celso Von Randow, Bradley O. Christoffersen Apr 2016

Variation In Stem Mortality Rates Determines Patterns Of Above-Ground Biomass In Amazonian Forests: Implications For Dynamic Global Vegetation Models, Michelle O. Johnson, David R. Galbraith, Manuel Gloor, Hannes De Deurwaerder, Matthieu Guimberteau, Anja Rammig, Kirsten Thonicke, Hans Verbeeck, Celso Von Randow, Bradley O. Christoffersen

Biology Faculty Publications and Presentations

Understanding the processes that determine above-ground biomass (AGB) in Amazonian forests is important for predicting the sensitivity of these ecosystems to environmental change and for designing and evaluating dynamic global vegetation models (DGVMs). AGB is determined by inputs from woody productivity [woody net primary productivity (NPP)] and the rate at which carbon is lost through tree mortality. Here, we test whether two direct metrics of tree mortality (the absolute rate of woody biomass loss and the rate of stem mortality) and/or woody NPP, control variation in AGB among 167 plots in intact forest across Amazonia. We then compare these relationships …

Go to article

Convergence Of Detrital Stoichiometry Predicts Thresholds Of Nutrient-Stimulated Breakdown In Streams, David W. P. Manning, Amy D. Rosemond, Vladislav Gulis, Jonathan P. Benstead, John S. Kominoski, John C. Maerz Jan 2016

Convergence Of Detrital Stoichiometry Predicts Thresholds Of Nutrient-Stimulated Breakdown In Streams, David W. P. Manning, Amy D. Rosemond, Vladislav Gulis, Jonathan P. Benstead, John S. Kominoski, John C. Maerz

Biology Faculty Publications

Nutrient enrichment of detritus‐based streams increases detrital resource quality for consumers and stimulates breakdown rates of particulate organic carbon (C). The relative importance of dissolved inorganic nitrogen (N) vs. phosphorus (P) for detrital quality and their effects on microbial‐ vs. detritivore‐mediated detrital breakdown are poorly understood. We tested effects of experimental N and P additions on detrital stoichiometry (C:N, C:P) and total and microbial breakdown (i.e., with and without detritivorous shredders, respectively) of five detritus types (four leaf litter species and wood) with different initial C : nutrient content. We enriched five headwater streams continuously for two years at different …

Go to article

Density Management In Young Western Larch Stands: Tree Growth, Stand Yield, And Carbon Storage 54 Years After Thinning, Michael S. Schaedel Jan 2016

Density Management In Young Western Larch Stands: Tree Growth, Stand Yield, And Carbon Storage 54 Years After Thinning, Michael S. Schaedel

Graduate Student Theses, Dissertations, & Professional Papers

Long-term silvicultural experiments can be used to test novel ecological hypotheses and answer contemporary management questions that were not envisioned at study initiation. We used a 54-year old western larch precommercial thinning (PCT) study in northwest Montana to examine two sets of questions: (1) how different PCT regimes affect long-term stand yield and tree growth, and (2) how PCT affects total aboveground carbon (C) storage and distribution among C pools. The study has three target densities (494 trees ha-1, 890 trees ha-1, and 1680 trees ha-1) and three numbers of entries to achieve those …

Go to article

Ecosystem Services Of Woody Crop Production Systems, Ronald S. Zalesny Jr., John A. Stanturf, Emile S. Gardiner, James H. Perdue, Timothy M. Young, David R. Coyle, William L. Headlee, Gary S. Bañuelos, Amir Hass Jan 2016

Ecosystem Services Of Woody Crop Production Systems, Ronald S. Zalesny Jr., John A. Stanturf, Emile S. Gardiner, James H. Perdue, Timothy M. Young, David R. Coyle, William L. Headlee, Gary S. Bañuelos, Amir Hass

USDA Forest Service / UNL Faculty Publications

Short-rotation woody crops are an integral component of regional and national energy portfolios, as well as providing essential ecosystem services such as biomass supplies, carbon sinks, clean water, and healthy soils. We review recent USDA Forest Service Research and Development efforts from the USDA Biomass Research Centers on the provisioning of these ecosystem services from woody crop production systems. For biomass, we highlight productivity and yield potential, pest susceptibility, and bioenergy siting applications. We describe carbon storage in aboveground woody biomass and studies assessing the provision of clean and plentiful water. Soil protection and wildlife habitat are also mentioned, in …

Go to article

Empirical Algorithms To Estimate Water Column Ph In The Southern Ocean, N. L. Williams, L. W. Juranek, K. S. Johnson, R. A. Feely, S. C. Riser, L. D. Talley, J. L. Russell, J. L. Sarmiento, R. Wanninkhof Jan 2016

Empirical Algorithms To Estimate Water Column Ph In The Southern Ocean, N. L. Williams, L. W. Juranek, K. S. Johnson, R. A. Feely, S. C. Riser, L. D. Talley, J. L. Russell, J. L. Sarmiento, R. Wanninkhof

Marine Science Faculty Publications

No abstract provided.

Go to article

Studies On Hydroxyl Radical Formation And Correlated Photoflocculation Process Using Degraded Wood Leachate As A Cdom Source, Luni Sun, Kenneth Mopper Jan 2016

Studies On Hydroxyl Radical Formation And Correlated Photoflocculation Process Using Degraded Wood Leachate As A Cdom Source, Luni Sun, Kenneth Mopper

Chemistry & Biochemistry Faculty Publications

In this study, we examined hydroxyl radical (•OH) formation with respect to photoreactivity of colored dissolved organic matter (CDOM), the Fenton reaction, and photoflocculation using leachate from decaying wood. The relationship between •OH photoproduction rate and leachate optical properties (UV-visible absorption and fluorescence excitation-emission matrices (EEMS)) was studied during irradiation using a UV solar simulator. The results showed that the •OH photochemical formation rate is strongly related to humic-like fluorescence as characterized by parallel factor analysis (PARAFAC), and that these fluorescence components are more photolabile than most of the other CDOM components. Fourier transform infrared spectroscopy (FT-IR) indicated the photodegradation …

Go to article