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Full-Text Articles in Physical Sciences and Mathematics

The North American Carbon Program Multi-Scale Synthesis And Terrestrial Model Intercomparison Project – Part 1: Overview And Experimental Design, D. N. Huntzinger, C. Schwalm, A, M, Michalak, K. Schaefer, A. W. King, Y. Wei, A. Jacobson, S. Liu, R. B. Cook, W. M. Post, G. Berthier, D Hayes, M. Huang, A. Ito, H. Lei, Chaoqun (Crystal) Lu, J. Mao, C. H. Peng, S. Peng, B. Poulter, D. Ricciuto, X. Shi, Hanqin Tian, W. Wang, N. Zeng, F. Zhao, Q. Zhu Dec 2013

The North American Carbon Program Multi-Scale Synthesis And Terrestrial Model Intercomparison Project – Part 1: Overview And Experimental Design, D. N. Huntzinger, C. Schwalm, A, M, Michalak, K. Schaefer, A. W. King, Y. Wei, A. Jacobson, S. Liu, R. B. Cook, W. M. Post, G. Berthier, D Hayes, M. Huang, A. Ito, H. Lei, Chaoqun (Crystal) Lu, J. Mao, C. H. Peng, S. Peng, B. Poulter, D. Ricciuto, X. Shi, Hanqin Tian, W. Wang, N. Zeng, F. Zhao, Q. Zhu

Chaoqun (Crystal) Lu

Terrestrial biosphere models (TBMs) have become an integral tool for extrapolating local observations and understanding of land–atmosphere carbon exchange to larger regions. The North American Carbon Program (NACP) Multi-scale synthesis and Terrestrial Model Intercomparison Project (MsTMIP) is a formal model intercomparison and evaluation effort focused on improving the diagnosis and attribution of carbon exchange at regional and global scales. MsTMIP builds upon current and past synthesis activities, and has a unique framework designed to isolate, interpret, and inform understanding of how model structural differences impact estimates of carbon uptake and release. Here we provide an overview of the MsTMIP effort …


Will Hubbard Brook Soils Be A Source Or Sink Of Carbon In A Changing Climate?, Chris E. Johnson Jul 2013

Will Hubbard Brook Soils Be A Source Or Sink Of Carbon In A Changing Climate?, Chris E. Johnson

Chris E Johnson

No abstract provided.


The World’S Deepest Subterranean Community - Krubera-Voronja Cave (Western Caucasus), Alberto Sendra, Ana Sofia P.S. Reboleira Jun 2013

The World’S Deepest Subterranean Community - Krubera-Voronja Cave (Western Caucasus), Alberto Sendra, Ana Sofia P.S. Reboleira

Ana Sofia P.S. Reboleira

Subsurface biota extends over a wide variety of habitats that can be spatially interconnected. The largest communities of this subsurface biota inhabit cavities and are well known mainly in caves where biologists are able to have access. Data about deep subterranean communities and arthropods living under one thousand meters was unknown. An expedition to world’s deepest cave, Krubera-Voronja in Western Caucasus, revealed an interesting subterranean community, living below 2000 meters and represented by more than 12 species of arthropods, including several new species for science. This deep cave biota is composed of troglobionts and also epigean species, that can penetrate …


Effect Of Continued Nitrogen Enrichment On Greenhouse Gas Emissions From A Wetland Ecosystem In The Sanjiang Plain, Northeast China: A 5 Year Nitrogen Addition Experiment, Changchun Song, Lili Wang, Hanqin Tian, Deyan Liu, Chaoqun (Crystal) Lu, Xiaofeng Xu, Lihua Zhang, Guisheng Yang, Zhongmei Wan Jun 2013

Effect Of Continued Nitrogen Enrichment On Greenhouse Gas Emissions From A Wetland Ecosystem In The Sanjiang Plain, Northeast China: A 5 Year Nitrogen Addition Experiment, Changchun Song, Lili Wang, Hanqin Tian, Deyan Liu, Chaoqun (Crystal) Lu, Xiaofeng Xu, Lihua Zhang, Guisheng Yang, Zhongmei Wan

Chaoqun (Crystal) Lu

Mounting evidence supports that wetland ecosystems, one of the largest carbon pools on the earth, are exposed to ample nitrogen (N) additions due to atmospheric deposition or N loading from upstream agricultural fertilizer application. However, our understanding of how N enrichment affects the fluxes of greenhouse gases (GHGs) in wetlands is weak. A 5 year N addition experiment was conducted to examine the responses of CH4 and N2O fluxes as well as ecosystem respiration from wetlands in the Sanjiang Plain, Northeast China, through 2005 to 2009. Four levels of N addition (control, 0 kg N ha−1 yr−1; low-level, 60 kg …


The Contribution Of Fe (Iii) And Humic Acid Reduction To Ecosystem Respiration In Drained Thaw Lake Basins Of The Arctic Coastal Plain, David A. Lipson, Ted K. Raab, Dominic Goria, Jaime Zlamal May 2013

The Contribution Of Fe (Iii) And Humic Acid Reduction To Ecosystem Respiration In Drained Thaw Lake Basins Of The Arctic Coastal Plain, David A. Lipson, Ted K. Raab, Dominic Goria, Jaime Zlamal

Ted K. Raab

Previous research showed that anaerobic respiration using iron (Fe) oxides as terminal electron acceptor contributed substantially to ecosystem respiration (ER) in a drained thaw lake basin (DTLB) on the Arctic coastal plain. As DTLB age, the surface organic layer thickens, progressively burying the Fe-rich mineral layers. We therefore hypothesized that Fe (III) availability and Fe reduction would decline with basin age. We studied four DTLB across an age gradient, comparing seasonal changes in the oxidation state of dissolved and extractable Fe pools and the estimated contribution of Fe reduction to ER. The organic layer thickness did not strictly increase with …


Trials Of The Urban Ecologist, Rebecca W. Dolan, Tim Carter, Travis J. Ryan, Carmen M. Salsbury, Thomas E. Dolan, Marjorie Hennessy May 2013

Trials Of The Urban Ecologist, Rebecca W. Dolan, Tim Carter, Travis J. Ryan, Carmen M. Salsbury, Thomas E. Dolan, Marjorie Hennessy

Rebecca W. Dolan

A group of scientists describe some of the obstacles encountered and insights gained while carrying out ecological research in and around the city of Indianapolis.


Confronting Socially Generated Uncertainty In Adaptive Management, Andrew J. Tyre, Sarah Michaels Apr 2013

Confronting Socially Generated Uncertainty In Adaptive Management, Andrew J. Tyre, Sarah Michaels

Andrew J Tyre

As more and more organizations with responsibility for natural resource management adopt adaptive management as the rubric in which they wish to operate, it becomes increasingly important to consider the sources of uncertainty inherent in their endeavors. Without recognizing that uncertainty originates both in the natural world and in human undertakings, efforts to manage adaptively at the least will prove frustrating and at the worst will prove damaging to the very natural resources that are the management targets. There will be more surprises and those surprises potentially may prove at the very least unwanted and at the worst devastating. We …


Evaluating The Efficacy Of Adaptive Management Approaches: Is There A Formula For Success?, Jamie E. Mcfadden, Tim L. Hiller, Andrew J. Tyre Apr 2013

Evaluating The Efficacy Of Adaptive Management Approaches: Is There A Formula For Success?, Jamie E. Mcfadden, Tim L. Hiller, Andrew J. Tyre

Andrew J Tyre

Within the field of natural-resources management, the application of adaptive management is appropriate for complex problems high in uncertainty. Adaptive management is becoming an increasingly popular management-decision tool within the scientific community and has developed into two primary schools of thought: the Resilience-Experimentalist School (with high emphasis on stakeholder involvement, resilience, and highly complex models) and the Decision-Theoretic School (which results in relatively simple models through emphasizing stakeholder involvement for identifying management objectives). Because of these differences, adaptive management plans implemented under each of these schools may yield varying levels of success. We evaluated peer-reviewed literature focused on incorporation of …


Nest And Brood Survival And Habitat Selection Of Ring-Necked Pheasants And Greater Prairie-Chickens In Nebraska, Ty Matthews Apr 2013

Nest And Brood Survival And Habitat Selection Of Ring-Necked Pheasants And Greater Prairie-Chickens In Nebraska, Ty Matthews

Andrew J Tyre

Ring-Necked Pheasant (Phasianus colchicus) and Greater Prairie-chicken (Tympanuchus cupido pinnatus) populations have declined in the Midwest since the 1960’s. Research has suggested decreased nest and brood survival are the major causes of this decline due to the lack of suitable habitat. Habitat degradation has been attributed to the shift to larger crop fields, lower diversity of crops, and more intensive pesticide and herbicide use. A primary goal of the Conservation Reserve Program (CRP) is to mitigate the loss of wildlife habitat. Early research found that CRP increased the amount of suitable nesting and brood rearing cover for both species but …


Integrating Info-Gap Decision Theory With Robust Population Management: A Case Study Using The Mountain Plover, Max Post Van Der Burg, Andrew J. Tyre Apr 2013

Integrating Info-Gap Decision Theory With Robust Population Management: A Case Study Using The Mountain Plover, Max Post Van Der Burg, Andrew J. Tyre

Andrew J Tyre

Wildlife managers often make decisions under considerable uncertainty. In the most extreme case, a complete lack of data leads to uncertainty that is unquantifiable.Information-gap decision theory deals with assessing management decisions under extreme uncertainty, but it is not widely used in wildlife management. So too, robust population management methods were developed to deal with uncertainties in multiple-model parameters.However, the two methods have not, as yet, been used in tandem to assess population management decisions. We provide a novel combination of the robust population management approach for matrix models with the information-gap decision theory framework for making conservation decisions under extreme …


Continuous, Pulsed And Disrupted Nutrient Subsidy Effects On Ecosystem Productivity, Stability, And Energy Flow, Michael J. Weber, Michael L. Brown Feb 2013

Continuous, Pulsed And Disrupted Nutrient Subsidy Effects On Ecosystem Productivity, Stability, And Energy Flow, Michael J. Weber, Michael L. Brown

Michael J Weber Dr

Resource pulses and subsidies can supply ecosystems with an important source of nutrients that supports additional productivity at multiple trophic levels. Common carp Cyprinus carpio provide ecosystems with a continuous nutrient subsidy through bioturbation and excretion but may also initiate a nutrient pulse through carcass decomposition. We examined how continuous (common carp foraging and excretion), pulsed (carcass decomposition) and disrupted (carp introduced and then removed) nutrient subsidies differed in their ability to alter nutrient availability, ecosystem productivity and stability and energy flow. Nitrogen and phosphorus availability and primary production were highest in pulsed, intermediate in continuous and lowest for disrupted …


Inhibition Of Bacillus Cereus Growth By Bacteriocin Producing Bacillus Subtilis Isolated From Fermented Baobab Seeds (Maari) Is Substrate Dependent, Donatien Kaboré, Dennis S. Nielsen, Hagrétoui Sawadogo-Lingan, Bréhima Diawara, Mamoudou H. Dicko Prof., Mogens Jakobsen, Line Thorsen Jan 2013

Inhibition Of Bacillus Cereus Growth By Bacteriocin Producing Bacillus Subtilis Isolated From Fermented Baobab Seeds (Maari) Is Substrate Dependent, Donatien Kaboré, Dennis S. Nielsen, Hagrétoui Sawadogo-Lingan, Bréhima Diawara, Mamoudou H. Dicko Prof., Mogens Jakobsen, Line Thorsen

Pr. Mamoudou H. DICKO, PhD

Maari is a spontaneously alkaline fermented food condiment made from baobab tree seeds. Due to the spontaneous nature of maari fermentations growth of the opportunistic human pathogen Bacillus cereus is occasionally observed. Bacillus subtilis strains are important for alkaline seed fermentations because of their enzymatic activities contributing to desirable texture, flavor and pH development. Some B. subtilis strains have antimicrobial properties against B. cereus. In the present work, three bacteriocin producing B. subtilis strains (B3, B122 and B222) isolated from maari were tested. The production of antimicrobial activity by the three strains was found to be greatly influenced by the …


Site Assessment For Environmental Restoration, David A. Bainbridge Jan 2013

Site Assessment For Environmental Restoration, David A. Bainbridge

David A Bainbridge

Restoring degraded desert ecosystems is challenging but it can be done. The first key step is understanding the site history and understanding the disturbance and current site conditions. With this information the appropriate steps can be taken to improve the site ecosystem function and structure.


Classification Of The Alterations Of Beaver Dams To Headwater Streams In Northeastern Connecticut, U.S.A., Denise Burchsted, Melinda D. Daniels Jan 2013

Classification Of The Alterations Of Beaver Dams To Headwater Streams In Northeastern Connecticut, U.S.A., Denise Burchsted, Melinda D. Daniels

Denise Burchsted

Of the many types of barriers to water flow, beaver dams are among the smallest, typically lasting less than a decade and rarely exceeding 1.5 m in height. They are also among the most frequent and common obstructions in rivers, with a density often exceeding ten dams per km, a frequency of construction within a given network on a time scale of years, and a historic extent covering most of North America. Past quantification of the geomorphologic impact of beaver dams has primarily been limited to local impacts within individual impoundments and is of limited geographic scope. To assess the …


Insights Into Forest Soil Carbon Dynamics From Nuclear Magnetic Resonance Spectroscopy, Chris E. Johnson Jan 2013

Insights Into Forest Soil Carbon Dynamics From Nuclear Magnetic Resonance Spectroscopy, Chris E. Johnson

Chris E Johnson

No abstract provided.


Sharing A Vision For Biodiversity Conservation And Agriculture, John Quinn Dec 2012

Sharing A Vision For Biodiversity Conservation And Agriculture, John Quinn

John E Quinn

No abstract provided.


The “Curse Of Rafinesquina:” Negative Taphonomic Feedback Exerted By Strophomenid Shells On Storm-Buried Lingulids In The Cincinnatian Series (Katian, Ordovician) Of Ohio, Rebecca Freeman, Benjamin Dattilo, Aaron Morse, Michael Blair, Steve Felton, John Pojeta Dec 2012

The “Curse Of Rafinesquina:” Negative Taphonomic Feedback Exerted By Strophomenid Shells On Storm-Buried Lingulids In The Cincinnatian Series (Katian, Ordovician) Of Ohio, Rebecca Freeman, Benjamin Dattilo, Aaron Morse, Michael Blair, Steve Felton, John Pojeta

Benjamin F. Dattilo

Taphonomic feedback is the idea that accumulation of organic remains either enhances the habitat for some organisms (positive taphonomic feedback), and/or degrades the habitat for others (negative taphonomic feedback). Examples of epibionts living on skeletal remains are direct evidence of positive taphonomic feedback. Disruption of infaunal burrowing activities by skeletal fragments is an example of negative taphonomic feedback; direct fossil evidence of this phenomenon has not been documented previously. Infaunal organisms are vulnerable to exhumation or entombment during storms, but organisms that burrow can also re-establish viable life positions subsequently. For example, when modern lingulids re-burrow after exhumation, they first …


Evolutionary Adaptation Of Marine Zooplankton To Global Change, Hans Dam Dec 2012

Evolutionary Adaptation Of Marine Zooplankton To Global Change, Hans Dam

Hans G. Dam

Predicting the response of the biota to global change remains a formidable endeavor. Zooplankton face challenges related to global warming, ocean acidification, the proliferation of toxic algal blooms, and increasing pollution, eutrophication, and hypoxia. They can respond to these changes by phenotypic plasticity or genetic adaptation. Using the concept of the evolution of reaction norms, I address how adaptive responses can be unequivocally discerned from phenotypic plasticity. To date, relatively few zooplankton studies have been designed for such a purpose. As case studies, I review the evidence for zooplankton adaptation to toxic algal blooms, hypoxia, and climate change. Predicting the …