Regional mapping of the South Armorican shear zone (Brittany, France) using remotely sensed SPOT imagery     

Herv Ysou  Joel Rolet 《ISPRS Journal of Photogrammetry and Remote Sensing》1990,45(5-6)

The South Armorican shear zone is one of the major occurrences of Variscan basement in Europe. The objectives of the study were to compile a lineament and a structural map from remotely sensed SPOT imagery. Transparent color films, enhanced by high-pass filtering and by stretching color composites, and spatial filtered images were analysed. The major structure mapped corresponds to a dextral transcurrent shear belt in which C and S axes have been described. Late Paleozoic and Tertiary fracturations truncate these structures. The localisation, extension and geometry of granite domes were also precised. Lastly, this study provides a good example of structural interpretation of a moderate-relief terrain using high-resolution SPOT imagery.  相似文献   

Hydrogeological Decision Analysis: 1. A Framework   总被引：6，自引：0，他引：6  

R. Allan Freeze  Joel Massmann  Leslie Smith  Tony Sperling  Bruce James 《Ground water》1990,28(5):738-766

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Comparisons of Three Methods to Determine the Vertical Stratification of Pore Fluids     

Kendrick Taylor  John Hess  Aldo Mazzella  Joel Hayworth 《Ground Water Monitoring & Remediation》1990,10(1):91-95

Three methods were used to investigate the possibility of vertical stratification of the pore fluid in an aquifer. The wells available for the study were fully screened and had a 5cm disturbed annulus around them. The first method used a pump with a straddle packer to isolate a short section of the secreened interval. A tracer test demonstrated that most of the pumped sample came from the well bore, presumably by piping through the disturbed. annulus. The second method used induction logs to measure the formation electrical conductivity as a function of depth. Due to the presence of clays and an inability to obtain porosity information, it was not possible to determine the pore fluid electrical conductivity using induction logs. A third method, dilution sampling, was developed that used a straddle packer to isolate a segment of the well screen. A tracer was injected into the packed-off segment, and the tracer concentration in the well was monitored. The tracer was removed from the packed-off segment by dilution and advection by ground water. When the tracer was completely removed from the packed-off segment, the fluid in the segment was considered to be representative of the adjacent pore fluid. Only the dilution sampling method determined unambiguously that the pore fluid was not stratified.  相似文献   

Cloud cover climatologies in the Mediterranean obtained from satellites,surface observations,reanalyses, and CMIP5 simulations: validation and future scenarios     

Aaron Enriquez-Alonso  Arturo Sanchez-Lorenzo  Josep Calbó  Josep-Abel González  Joel R. Norris 《Climate Dynamics》2016,47(1-2):249-269

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Disposition and metabolism of 2,3,7,8-tetrachlorodibenzofuran (TCDF) in rainbow trout     

A. Robert Maslanka  Ruth Steward  Jyotsna Pangrekar  Subodh Kumar  Harish C. Sikka   《Marine environmental research》1992,34(1-4)

In order to elucidate the metabolic fate of 2,3,7,8-tetrachlorodibenzofuran (TCDF) in fish and to thereby facilitate the assessment of the risks posed by this environmental toxin, we determined the whole body half-life, tissue distribution and metabolism of [³H TCDF in rainbow trout (Onchorynchus mykiss), treated orally. A whole body biphasic elimination pattern resulted in the excretion of 60% of the administered chemical during the first 3 days, after which a much slower elimination-rate (half-life = 14 days) was observed. Significant amounts of water-soluble metabolites were found in both bile and liver. Of the TCDF-derived radioactivity in bile, approximately 50% represented glucuronide conjugates, predominantly 4-hydroxy-2,3,7,8-TCDF: substantial amounts of the sulfate conjugate of this same metabolite were also present. Except at early time points, muscle contained the predominant fraction of TCDF-derived radioactivity, amounting to 25–65% of the total radioactivity present in the fish. More than 95% of the radioactivity present in muscle represented unmetabolized TCDF.  相似文献   

Mats of Beggiatoa bacteria reveal that organic pollution from lumber mills inhibits growth of Zostera marina     

Joel K. Elliott  Erin Spear  & Sandy Wyllie-Echeverria 《Marine Ecology》2006,27(4):372-380

The objectives of this study were to determine the distribution and abundance of Zostera marina (eelgrass) in relation to the distribution of the mat forming bacteria Beggiatoa spp., and the levels of sulfide and organic material (wood waste) in the sediment. Underwater videography and intertidal surveys were used to map the distribution and abundance of Z. marina beds and Beggiatoa in the nearshore area of Commencement Bay, WA (USA), a location that has a long history of sawmill activity. Zostera marina occurred from the intertidal to ?6 m mean lower low water (MLLW) on sandy substrates in areas with low levels of sulfide (<50 μm ) and organic material (<5 % total volatile solids). Areas with high sulfide levels (>200 μm ) occurred where there were significant amounts of organic material in the sediments, which was found to be wood waste that had been discarded from sawmills. Zostera marina was absent from the intertidal and occurred at lower densities in areas with high sulfide levels. In contrast, mats of Beggiatoa were only found in areas where the sulfide levels were >1000 μm and there were significant deposits of wood. Thus, the negative correlation between the distribution and abundance of Z. marina and Beggiatoa suggests that the presence of Beggiatoa mats could be used as a biological indicator of inhibiting levels of hydrogen sulfide in the marine environment.  相似文献   

Hydrologic‐response‐driven sediment transport at a regional scale,process‐based simulation     

Qihua Ran  Keith Loague  Joel E. VanderKwaak 《水文研究》2012,26(2):159-167

Assessing hydrologically driven erosion at regional scales from a process‐based perspective presents a significant challenge. Most regional‐scale erosion assessments are based upon a simple steady‐state hydrology foundation. For this study, the sediment transport version of the physics‐based Integrated Hydrology Model (InHM), excited by synthetically generated rainfall, was employed to assess long‐term hydrologically driven erosion for a regional‐scale island boundary‐value problem. The spatiotemporal dynamics of runoff generation, erosion, and deposition are illustrated through saturation, water depth, velocity, and sediment concentration results. The simulations demonstrate that process‐based assessment for concept development is both feasible and tractable at regional spatial and human time scales. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

The quixotic search for a comprehensive understanding of hydrologic response at the surface: Horton,Dunne, Dunton,and the role of concept‐development simulation     

Keith Loague  Christopher S. Heppner  Brian A. Ebel  Joel E. VanderKwaak 《水文研究》2010,24(17):2499-2505

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The USDA-Agricultural Research Service's long term agro-ecosystems Walnut Gulch Experimental Watershed,Arizona, USA     

David C. Goodrich  Philip Heilman  Mark Nearing  Mary Nichols  Russ L. Scott  C. Jason Williams  Joel Biederman 《水文研究》2021,35(9):e14349

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Evidence of a phase shift to Epizoanthus gabrieli Carlgreen, 1951 (Order Zoanthidea) and loss of coral cover on reefs in the Southwest Atlantic          下载免费PDF全文

Igor C. S. Cruz  Ruy K. P. de Kikuchi  Leila L. Longo  Joel C. Creed 《Marine Ecology》2015,36(3):318-325

There is at present a ‘coral reef crisis’; one of the more drastic consequences of this is a phase shift, in which reef‐building corals are replaced by non‐reef building benthos such as macroalgae and soft corals. Previous studies have principally focused on the shift to macroalgae. Our goal was to investigate whether the dominance of the zoanthid Epizoanthus gabrieli on some reefs of Todos os Santos Bay, Brazil, represented a non‐algal phase shift. In 2003, we identified a high cover of this species on two reefs (52% and 70%), but only in 2007 was it possible to confirm a reduction in coral cover. This dominance has persisted for over 9 years, characterizing a true phase shift. This loss of coral cover may be a result of anthropogenic disturbances within the bay; however, given the large number of human impacts, further studies are needed to identify specific causes of this shift. Although there are some reports of phase shift involving species pertaining to the Class Anthozoa, this is the first report of this phenomenon involving the order Zoanthidea.  相似文献