Observations of the Sediment-Water Interface: Marine and Fresh Water Environments     

Matthew H. Hulbert  Richard H. Bennett  Roy J. Baerwald  Richard L. Long  Kenneth J. Curry  Ann L. Curry  Maritza T. Abril 《Marine Georesources & Geotechnology》2002,20(4):255-274

The sediment at the interface immediately beneath the water column is distinct from deeper-lying sediments in its properties and, at least quantitatively, in the processes driving diagenesis. Progress in understanding the sediment-water interface can be based on consideration of fundamentals of biogeochemical particle / fluid interactions and on application of certain biological techniques especially suited to this challenging portion of the sediment column. This article reports results achieved by combining theoretical fundamentals and specialized experimental techniques in the study of the interface from selected depositional environments. For fine-grained and sandy deposits from fresh-water to coastal marine environments, the interface is characterized by exaggerated microrelief, great porosity, and significant biological alteration. Additional application of this research approach is poised to further our understanding of engineering, and acoustic and xenochemical responses of sedimentary materials, with special emphasis on the influence of the bio-organic phase of the interface upon its fabric and physical properties.  相似文献   

Constructing a coherent joint prior while respecting biological realism: application to marine mammal stock assessments   总被引：1，自引：0，他引：1  

Brandon  John R.; Breiwick  Jeffrey M.; Punt  Andre E.; Wade  Paul R. 《ICES Journal of Marine Science》2007,64(6):1085-1100

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Impact of Partially Cemented and Non-persistent Natural Fractures on Hydraulic Fracture Propagation     

Wei Fu  Brandon C. Ames  Andrew P. Bunger  Alexei A. Savitski 《Rock Mechanics and Rock Engineering》2016,49(11):4519-4526

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Holocene reworking of drift‐mantled hillslopes in the Scottish Highlands     

Alastair M. Curry 《第四纪科学杂志》2000,15(5):529-541

Episodic erosion and resedimentation of valley‐side glacigenic drift is evident at three sites in the Scottish Highlands in the form of buried in situ palaeosols intercalated with stacked sediment units. Radiocarbon dating of 10 palaeosols exposed in sections in debris cones suggests that gully erosion and redeposition of drift represents asynchronous debris flow and slopewash activity within the past 6⋅5 cal.kyr. Palynological and charcoal analyses confirm that reworking was unrelated to burning of vegetation, and post‐dated the main phase of anthropogenic woodland clearance at two sites, although the possibility that recent debris flow activity in Glen Docherty may have been associated with removal of woodland cover cannot be dismissed. However, the collective evidence points to discrete, extreme storm‐generated events of random occurrence as the most likely cause of episodes of enhanced slope reworking at the sites investigated. Evidence for periodic climatic deterioration is more equivocal. By implication, the accumulation of substantial debris cones in upland Britain may reflect primarily the reworking of sediment during extremely rare, intense rainstorms, essentially independent of progressive climate changes. Consequently, caution is necessary in using debris flow stratigraphies alone as a means of reconstructing former long‐term climatic changes. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

Forecasting the consequences of climate-driven shifts in human behavior on cetaceans     

S. Elizabeth Alter  Mark P. Simmonds  John R. Brandon 《Marine Policy》2010

While climate change is expected to affect cetaceans primarily via loss of habitat and changes in prey availability, additional consequences may result from climate-driven shifts in human behaviors and economic activities. For example, increases in shipping, oil and gas exploration and fishing due to the loss of Arctic sea ice are highly likely to exacerbate acoustic disturbance, ship strikes, bycatch and prey depletion for Arctic cetaceans. In the tropics, climate change may result in increased hunting pressure on near-shore dolphins and whales off Asia, Latin America, Africa, and elsewhere as the availability of other marine resources diminishes. This study explores the range of potential consequences to cetaceans worldwide from predicted climate-driven shifts in human behavior, and evaluates the risks to particular species given their geographic ranges and habitat preferences. While concern about impacts of climate change on cetaceans has largely focused on polar species, the analysis presented here suggests tropical coastal and riverine cetaceans such as the Irawaddy dolphin, Indo-Pacific humpback dolphin, and finless porpoise are particularly vulnerable to those aspects of climate change that are mediated by changes in human behavior. Policy recommendations include the following: (1) information about cetacean populations should be incorporated into national, regional and international climate adaptation decisions wherever possible (for example, via GEF-sponsored adaptation initiatives); and (2) human-mediated impacts of climate change should be included in cetacean conservation and management plans, such as the management procedures of the International Whaling Commission (IWC), where possible. Because human responses to climate change are likely to evolve rapidly over the coming years and decades, it is important that local, regional and international cetacean conservation and management plans include regular reviews to allow them to adapt to new information.  相似文献   

A new flow for Canadian young hydrologists: Key scientific challenges addressed by research cultural shifts     

Caroline Aubry-Wake  Lauren D. Somers  Haley Alcock  Aspen M. Anderson  Amin Azarkhish  Samuel Bansah  Nicole M. Bell  Kelly Biagi  Mariana Castaneda-Gonzalez  Olivier Champagne  Anna Chesnokova  Devin Coone  Tasha-Leigh J. Gauthier  Uttam Ghimire  Nathan Glas  Dylan M. Hrach  Oi Yin Lai  Pierrick Lamontagne-Hallé  Nicolas R. Leroux  Laura Lyon  Sohom Mandal  Bouchra R. Nasri  Nataša Popović  Tracy E. Rankin  Kabir Rasouli  Alexis Robinson  Palash Sanyal  Nadine J. Shatilla  Brandon Van Huizen  Sophie Wilkinson  Jessica Williamson  Majid Zaremehrjardy 《水文研究》2020,34(8):2001-2006

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Change and continuity in the Pacific: revisiting the region     

George N. Curry 《The Australian geographer》2020,51(1):125-127

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Reply to Iannicelli's (2012) Letter to the Editor     

B. Brandon Curry  Michael E. Konen  Timothy H. Larson  Catherine H. Yansa  Keith C. Hackley  Thomas V. Lowell  Justine Petras 《Quaternary Research》2012,77(2):332-334

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Toward an Immersive 3D Virtual BoK Exploratorium: A Proof of Concept     

Michael DeMers  Anna Klimaszewski‐Patterson  Rebecca Richman  Sean Ahearn  Brandon Plewe  André Skupin 《Transactions in GIS》2013,17(3):335-352

The UCGIS GIS&T Body of Knowledge document provided an opportunity for the GIS educational community to link course content and curricular sequencing to a catalog of subject matter. Focusing on learning objectives, a selection of relevant citations, and basic background for each topic, it has been used to a limited degree for both course topic selection and curriculum development. However, the static format of the document, lack of an index, and dated nature of the material limit its utility for education. Based on the success of our research team in developing a virtual platform for a new, more interactive, and collaborative environment to catalogue and interactively add to the body knowledge (Ahearn et al. 2013), this article describes efforts to develop a multi‐user virtual user environment that will add social presence to the experience. It describes the successes and failures of using Second Life as the initial platform for this work, illustrates the available interactions and limitations, and depicts ongoing efforts to move beyond Second Life for this development. Finally it discusses a possible methodology to leverage the power of virtual crowd sourcing within competitive gaming environments such as Unity to allow for the creation of on‐demand virtual 3‐D visualizations of GIS&T concepts in a digital Exploratorium.  相似文献   

Quantifying the spatial variability of melting seasonal ground ice and its influence on potential evapotranspiration spatial variability in a boreal peatland     

Brandon Van Huizen  Richard M. Petrone 《水文研究》2020,34(17):3683-3701

Melting seasonal ground ice (SGI) in western Boreal Plains (WBP) peatlands can reduce the available energy at the surface by reducing potential evapotranspiration (PET). PET often exceeds annual precipitation in the WBP. Including this effect in hydrological models may be important in assessing water deficits. However, SGI melt and the timing of ice-free conditions vary spatially, which suggests PET spatial variability could be influenced by SGI. Understanding this potential linkage can help improve site scale PET in peatland hydrological models. The objectives of this paper were (a) to quantify the effect of ice thickness and melt rate on peatland PET; (b) quantify the spatial variability of SGI thickness and melt rate across spatial scales; and (c) assess how/if spatial variability in SGI thickness/melt rate affects site scale PET. Results from the sensitivity analysis indicated that SGI thickness had a bigger impact on reducing PET compared with the melt rate. Two SGI thickness values were used that were observed on site: 0.32 m, which was measured in a more treed area, and 0.18 m, which was in a more open area. The 0.32 m had an average PET reduction of 14 mm (±0.7), over the month of May, compared with 9 mm (±1 mm) when there was 0.18 m of SGI, which are 13.7 and 8.8% reductions, respectively. SGI thickness and melt rate, both exhibited large- and small-scale spatial variability. At the large scale, spatial patterns in SGI thickness appeared to be influenced by extensive shading from the adjacent hillslopes. Small scale, SGI thickness may be a function of tree proximity and the snowpack. Finally, net radiation, rather than SGI, appeared to be the main driver behind PET spatial variability. This work enhances our conceptual understanding of the role of SGI in WBP peatlands. Future work can use the findings to better inform peatland hydrological models, allowing for better representation of peatlands in regional-scale models.  相似文献