Investigation of runoff generation in a pristine,poorly gauged catchment in the Chilean Andes I: A multi‐method experimental study     

Theresa Blume  Erwin Zehe  Dominik E. Reusser  Andrés Iroumé  Axel Bronstert 《水文研究》2008,22(18):3661-3675

Catchment scale hydrological process studies in southern Chile are of special interest as little research at this scale has been carried out in this region. In particular, the young volcanic ash soils, which are typical for this area, are not well understood in their hydrological behaviour. In addition, extensive land use changes require detailed knowledge of hydrological processes in disturbed as well as undisturbed catchments in order to estimate resulting risks of erosion, eutrophication, floods and droughts. This study focuses on data collection and experimental determination of relevant processes in an undisturbed forested catchment in the Andes of southern Chile. The here gained understanding of runoff generation can serve as a reference for comparison with sites subject to human intervention, improving estimation of the effects of land use change. Owing to the lack of long‐term data for this catchment it was necessary to replace long time series by a multitude of experimental methods covering as many aspects of the runoff generation process as possible. The methods used in this investigation include: measurements of streamflow, rainfall, throughfall, water chemistry, soil water dynamics, groundwater dynamics, soil physics, soil mineralogy, geo‐electrical sounding, and tracer techniques. Methods and equipment used during field campaigns are described and evaluated for usefulness versus expenditure (labour and financial costs). Selected results and the hypotheses developed from these findings are presented. The results suggest the importance of fast processes for rainfall runoff response on the one hand as well as considerable dampening effects of a large subsurface storage on the other hand. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

A meteorite impact crater field in eastern Bavaria? A preliminary report     

Karl Thomas Fehr  Jean Pohl  Werner Mayer  Rupert Hochleitner  Jrg Fassbinder  Erwin Geiss  Hermann Kerscher 《Meteoritics & planetary science》2005,40(2):187-194

Abstract— Numerous circular depressions north of Burghausen in eastern Bavaria, with diameters ranging from meters to tens of meters in size and dispersed over an area of at least 11 times 7 km, are suspected to have an extraterrestrial origin since they resemble other small meteorite impact craters. The depressions are bowl‐shaped, have high circularity and a characteristic rim. Most of them were formed in unconsolidated glacial gravels and pebbles intermixed with fine‐grained sand and clay. Magnetic investigations reveal weak anomalies with amplitudes of less than ±10 nano Tesla (nT). In some cases, the origins of the anomalies are suspected to be due to human activity within the structures. So far, no traces of meteoritic material have been detected. An evident archaeological or local geological explanation for the origin of the craters does not exist. A World War I and II explosive origin can be excluded since trees with ages exceeding 100 years can be found in some craters. One crater was described in 1909. Carbon‐14 dating of charcoal found in one crater yielded an age of 1790 ± 60 years. Hence, a formation by meteorite impacts that occurred in Celtic or early medieval times should be considered. A systematic archaeological excavation of some structures and an intensified search for traces of meteoritic material are planned.  相似文献   

Chemometric study of functional groups in different layers of Trigonocarpus grandis ovules (Pennsylvanian seed fern, Canada)     

José A. D’Angelo  Erwin L. Zodrow 《Organic Geochemistry》2011,42(9):1039-1054

We examined four dispersed, coalified ovules, Trigonocarpus grandis, of medullosalean seed-fern affinity from the Late Pennsylvanian age Sydney Coalfield, Canada, which represent the larger type of the 7–8 cm trigonocarpalean form species. At first glance it appears that the ovules are preserved like the usual Carboniferous foliar compressions, i.e. one coalified layer with one preserved anatomical tissue, the cuticle. However, careful sample preparation uncovered at least three coalified layers, and Schulze’s oxidative maceration process, which dissolves the coalified material, revealed several tissue layers. Altogether, eight sample forms were defined: (i) coalified layer, (ii) cuticle A, (iii) cupric + vitrain, (iv) vitrain, (v) cupric, (vi) cuticle B, (vii) alkaline solution and (viii) added coal seam material. The purpose of the study was twofold: first, to systematically analyze the forms by way of Fourier transform infrared (FTIR) spectrometry to fill a gap in chemical information that exits for coalified trigonocarpalean ovules of Carboniferous seed ferns; second, to use principal component analysis to focus on groupings as a function of chemical structure (functional groups) and to assess the different fossil forms in terms of FTIR chemical parameters, based on a 8 × 49 data matrix.Results include distinction among the three coaly sample forms, coalified layer (i), cupric + vitrain (iii) and cupric (v), based mainly, but not exclusively, on differences in carbonyl content, as well as length and branching of the polymethylenic chains. Important to note is the high aliphatic content of the cuticles as a signature of the biomacromolecules cutan/cutin. In particular, new insights into the structure of the original ovule are presented, and differences in chemistry are mainly a result of the complex structure of the precursor plant organ.  相似文献   

Petrology, geochemistry, and geochronology of the Chah-Bazargan gabbroic intrusions in the south Sanandaj–Sirjan zone, Neyriz, Iran     

Abdolnaser Fazlnia  Volker Schenk  Peter Appel  Abouzar Alizade 《International Journal of Earth Sciences》2013,102(5):1403-1426

The Chah-Bazargan gabbroic intrusions are located in the south of Sanandaj–Sirjan zone. Precise U–Pb zircon SHRIMP ages of the intrusions show magmatic ages of 170.5 ± 1.9 Ma. These intrusions consist primarily of gabbros, interspersed with lenticular bodies of anorthosite, troctolite, clinopyroxenite, and wehrlite. The lenticular bodies show gradational or sharp boundaries with the gabbros. In the gradational boundaries, gabbros are mineralogically transformed into anorthosites, wehrlites, and/or clinopyroxenites. On the other hand, where the boundaries are sharp, the mineral assemblages change abruptly. There is no obvious deformation in the intrusions. Hence, the changes in mineral compositions are interpreted as the result of crystallization processes, such as fractionation in the magma chamber. Rock types with sharp boundaries show abrupt chemical changes, but the changes exhibit the same patterns of increasing and decreasing elements, especially of rare earth elements, as the gradational boundaries. Therefore, it is possible that all parts of the intrusions were formed from the same parental magma. Parts showing signs of nonequilibrium crystallization, such as cumulate features and sub-solidification, underwent fracturing and were interspersed throughout the magma chamber by late injection pulses or mechanical movements under mush conditions. The geological and age data show that the intrusions were formed from an Al-, Sr-, Fe-enriched and K-, Nb-depleted tholeiitic magma. The magma resulted from the partial melting of a metasomatized spinel demonstrated by negative Nb, P, Hf, and Ti, and positive Ba, Sr, and U anomalies typical of subduction-related magmas.  相似文献   

Magnetic properties of tree leaves and their significance in atmospheric particle pollution in Linfen City, China   总被引：2，自引：0，他引：2  

YIN Gang  HU Shouyun  CAO Liwan  Wolfgang ROESLER  Erwin APPEL 《中国地理科学(英文版)》2013,23(1):59-72

Fifty-one tree leaves were sampled in the industrial area,residential area,and Fenhe River ecological zone,for the purpose of a magnetic study on atmospheric pollution in Linfen City,Shanxi Province,China.Measurements of mass-specific magnetic susceptibility(χ) show a significant variation range(from 11.6 × 10-8 m3/kg to 129.7 × 10-8 m3/kg).Overall values of magnetic susceptibility decline in the following sequence:industrial area > residential area > Fenhe River ecological zone.The relatively elevated concentration-related magnetic parameters(saturation isothermal remanent magnetization,anhysteretic remanent magnetization and magnetic susceptibility) appear in the industrial area,with their highest values in the vicinity of Linfen Steel Mill.Magnetic particles are dominated by multidomain,magnetite-like minerals.Magnetic particle concentration and grain size both decrease with the increasing distance from industrial area,indicating the industrial area,especially Linfen Steel Mill,is the main source of atmospheric particle pollution.Residential area and Fenhe River ecological zone are also affected by industrial emission to a certain extent.The results of this study indicate that magnetic measurements of tree leaves are practicable for monitoring and determination of atmospheric pollution in Linfen City.  相似文献   

Combined Sea Surface Determination Based on Various Geometric and Dynamic Techniques     

Erwin Groten  Tilman Muller 《Marine Geodesy》2013,36(3-4):185-195

Abstract

The combined use of Global Positioning System (GPS) differential positioning as well as ERS‐1 altimeter data is considered in implementing geodetic vertical datums and their unification. The article describes concepts, techniques, practical realization, and associated questions and problems. Particular aspects in view of small sea surface perturbations in offshore areas in determining sea surface components (variable and steady state) are discussed. The combinations of tide gauge data with altimetry and (mainly) GPS positioning for geodetic purposes are discussed in detail. Special attention is devoted to the associated reference systems as well as to the combination of dynamic (level and nonlevel surfaces) with geometric quantities. The discussion is based on a specific ERS‐1 project supported by the National Science Foundation. Implications and practical impact of the project are outlined.  相似文献   

Correction to: The enhanced element enrichment in the supercritical states of granite–pegmatite systems     

Thomas  Rainer  Davidson  Paul  Appel  Karen 《中国地球化学学报》2019,38(3):456-457

Acta Geochimica - In the original publication, there are some missing data in Table 1 and incorrect data in Table 2.  相似文献   

Absolute orientation of an astro-geodetic geoid section and its correlation with geophysical data     

Erwin Groten 《Studia Geophysica et Geodaetica》1970,14(2):212-221

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Use of normalized metal concentrations in the Mn oxides/hydrous oxides extraction phase of stream sediments to enhance the difference between a landfill emission plume and background     

Erwin J. Mantei  Melida Gutierrez  Yia-Dong Zhou 《Applied Geochemistry》1996,11(6):803-810

Normalized concentrations of Fe, Zn, Ba and Co bound to the Mn phase were determined using a ratio of metal concentration to Mn concentration. Metal concentrations were taken from a previous study which found elevated concentrations of heavy metals in the stream sediments in the vicinity of 2 landfills using a HN0₃ extraction of the whole sediment sample and geochemical phases. Results from the normalized metal concentrations for Zn, Fe and Ba showed a clearer distinction between background and emission plume regions along the stream compared to the same for the HN0₃ and Mn phase extractions. Lack of elevated concentrations and normalized concentrations for Co indicated the concentrations represented the background. The small distance used in the study could explain the lack of a decreasing trend of metal concentrations and normalized metal concentrations downstream in the emission plume of the sediments. Although Mn⁺² 2concentrations are known to be incorporated into the natural state of the Mn phase, these concentrations were thought to be small enough not to influence the results from the normalized concentrations. Non-selectivity of extractants and metal redistribution among chemical phases during extraction procedures are thought to be small and did not invalidate the results.  相似文献   

Dependence of waterbirds and shorebirds on shallow-water habitats in the Mid-Atlantic coastal region: An ecological profile and management recommendations     

R. Michael Erwin 《Estuaries and Coasts》1996,19(2):213-219

Waterbirds (waterfowl, colonially nesting wading and seabirds, ospreys [Pandion haliaetus], and bald eagles [Haliaeetus leucocephalus]) and shorebirds (sandpipers, plovers, and relatives) may constitute a large fraction of the toplevel carnivore trophic component in many shallow-water areas of the mid-Atlantic region. The large biomass of many species (>1 kg body mass for the two raptors and some waterfowl) and enormous populations (e.g.,>1 million shorebirds in late May in parts of Delaware Bay) reveal the importance of waterbirds as consumers and as linkages in nutrient flux in many shallow-water habitats. Salt and brackish marsh shallow-water habitats, including marsh pannes and tidal pools and creeks as well as constructed impoundments, are used intensively during most months of the year; in fall and winter, mostly by dabbling ducks, in spring and summer by migrant shorebirds and breeding colonial wading birds and seabirds. In adjacent estuaries, the intertidal flats and littoral zones of shallow embayments are heavily used by shorebirds, raptors, and colonial waterbirds in the May to September periods, with use by duck and geese heaviest from October to March. With the regional degradation of estuarine habitats and population declines of many species of waterbirds in the past 20 yr, some management recommedations relevant to shallow waters include: better protection, enhancement, and creation of small bay islands (small and isolated to preclude most mammalian predators) for nesting and brooding birds, especially colonial species; establishment of sanctuaries from human disturbance (e.g., boating, hunting) both in open water (waterfowl) and on land; better allocation of sandy dredged materials to augment islands or stabilize eroding islands; improvement in water management of existing impoundments to ensure good feeding, resting, and nesting opportunities for all the waterbirds; support for policies to preclude point and nonpoint source runoff of chemicals and nutrients to enable submerged aquatic vegetation to recover in many coastal bays; and improvement in environmental education concerning disturbance to wildlife for boaters and recreationists using the coastal zone. *** DIRECT SUPPORT *** A01BY074 00007  相似文献