Book review     

Petr Jakeš  Marck Wolf 《Earth, Moon, and Planets》1995,71(1-2):175-176

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Formation of patterned ground and fine-scale soil development within two late Holocene glacial chronosequences: Jotunheimen, Norway     

Jake E. Haugland   《Geomorphology》2004,61(3-4):287-301

Chronosequences of 250 to 130 years were established on two late Holocene glacier forelands in the Jotunheimen region of southern Norway. Patterned features occurring within chronologically established time units were studied. Young patterned features, forming 10–20 years after deglaciation, are frost active. Vegetation cover is minimal within the young patterned features, consisting of bryophytes/organic crusts. Soil development within patterned ground is also minimal/absent because frost action retards horizonization. With time and distance from the glaciated ice margin, frost activity declines within the patterned features, suggesting that a thin, active “periglacial zone” exists near the ice margin. Initially, frost activity decreases at the borders of the features with the centers stabilizing later in time. This results in fine-scale soil heterogeneity and variations of soil development. Fine-scale pedogenic development is first encountered at the borders of patterned ground that has developed on terrain exposed since the 1930s, yet soil development is predominantly absent at the centers of patterned ground. With time and distance from the ice margin, frost activity declines and allows patterned features to homogenize from border to center positions in regard to soil characteristics. Across the chronosequences, soils within patterned features pedogenically follow previous soil chronosequence studies, evolving from USDA classifications of Entisols into Inceptisols. Frost disturbance within patterned ground, however, produces a lag effect, that results in longer periods of time for pedogenesis to occur and thinner soils than that of the surrounding terrain.  相似文献   

Der Einfluß der Komplexierung auf die Kupfertoxizität bei Blaualgen     

V. Lüderitz  F. Scholz  A. Nicklisch  S. Krause 《洁净——土壤、空气、水》1989,17(6):647-658

Some aspects of the influence of copper speciation on toxicity for blue-green algae are reviewed. The experimental part concentrates on Oscillatoria redekei and Aphanizomenon gracile. The two investigated species produce strong extracellular copper complexing ligands: Oscillatoria redekei in the exponential and stationary growth phase, and Aphanizomenon gracile has a distinct detoxification capacity. The detoxification of copper by synthetic agents was investigated using ethylene-diamine-tetraacetic acid. Simultaneous addition of Cu²⁺ and Na₂EDTA gives evidence for a slow complexation reaction. Hence an excess of Na₂EDTA is necessary for a fast and complete detoxification of copper. Model calculations are reported to show that the precipitation of copper compounds is not probable under the conditions used.  相似文献   

High potassium calc-alkaline rocks from Cape Nelson,eastern Papua     

P. Jakeš  I. E. Smith 《Contributions to Mineralogy and Petrology》1970,28(4):259-271

High-K calc-alkaline rocks from Cape Nelson, eastern Papua are dominated by andesites containing numerous basic inclusions. High-Al basalts and dacites are subordinate. The slight iron enrichment and a systematic variation in K₂O/SiO₂ correlation observed in these rocks suggests a relationship to nearby rocks of a shoshonite association. The chemical composition of the inclusions illustrates the trends of major and minor element evolution which contradict the idea of complimentariness of high-K calc-alkaline rocks and alpine ultramafic rocks. The chemical character of the lavas (high K, Rb and Ba as well as high Cr and Ni) can be explained by fractional melting involving a mica phase.  相似文献   

Brendelite, (Bi,Pb)2Fe3+,2+O2(OH)(PO4), a new mineral from Schneeberg, Germany: Description and crystal structure     

W. Krause  H. -J. Bernhardt  C. McCammon  H. Effenberger 《Mineralogy and Petrology》1998,63(3-4):263-277

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Patterns of change in the size spectra of numbers and diversity of the North Sea fish assemblage, as reflected in surveys and models   总被引：5，自引：12，他引：5  

Rice  Jake; Gislason  Henrik 《ICES Journal of Marine Science》1996,53(6):1214-1225

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Predicting recruitment from stock size without the mediation of a functional relation     

Evans  Geoffrey T.; Rice  Jake C. 《ICES Journal of Marine Science》1988,44(2):111-122

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The dual role of indicators in optimal fisheries management strategies     

Rice  Jake C.; Rivard  Denis 《ICES Journal of Marine Science》2007,64(4):775-778

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Development of Iron Speciation Reference Materials for Palaeoredox Analysis     

Lewis J. Alcott  Alexander J. Krause  Emma U. Hammarlund  Christian J. Bjerrum  Florian Scholz  Yijun Xiong  Andrew J. Hobson  Lesley Neve  Benjamin J. W. Mills  Christian Mrz  Bernhard Schnetger  Andrey Bekker  Simon W. Poulton 《Geostandards and Geoanalytical Research》2020,44(3):581-591

The development and application of geochemical techniques to identify redox conditions in modern and ancient aquatic environments has intensified over recent years. Iron (Fe) speciation has emerged as one of the most widely used procedures to distinguish different redox regimes in both the water column and sediments, and is the main technique used to identify oxic, ferruginous (anoxic, Fe(II) containing) and euxinic (anoxic, sulfidic) water column conditions. However, an international sediment reference material has never been developed. This has led to concern over the consistency of results published by the many laboratories that now utilise the technique. Here, we report an interlaboratory comparison of four Fe speciation reference materials for palaeoredox analysis, which span a range of compositions and reflect deposition under different redox conditions. We provide an update of extraction techniques used in Fe speciation and assess the effects of both test portion mass, and the use of different analytical procedures, on the quantification of different Fe fractions in sedimentary rocks. While atomic absorption spectroscopy and inductively coupled plasma‐optical emission spectrometry produced comparable Fe measurements for all extraction stages, the use of ferrozine consistently underestimated Fe in the extraction step targeting mixed ferrous–ferric minerals such as magnetite. We therefore suggest that the use of ferrozine is discontinued for this Fe pool. Finally, we report the combined data of four independent Fe speciation laboratories to characterise the Fe speciation composition of the reference materials. These reference materials are available to the community to provide an essential validation of in‐house Fe speciation measurements.  相似文献   

Water Treatment Technologies for PFAS: The Next Generation          下载免费PDF全文

John Horst  Jeff McDonough  Ian Ross  Michael Dickson  Jonathan Miles  Jake Hurst  Peter Storch 《Ground Water Monitoring & Remediation》2018,38(2):13-23

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