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241.
Hilke Würdemann Fabian Mller Michael Kühn Wolfgang Heidug Niels Peter Christensen Günter Borm Frank R. Schilling the COSINK Group 《International Journal of Greenhouse Gas Control》2010,4(6):938-951
The CO2SINK pilot project at Ketzin is aimed at a better understanding of geological CO2 storage operation in a saline aquifer. The reservoir consists of fluvial deposits with average permeability ranging between 50 and 100 mDarcy. The main focus of CO2SINK is developing and testing of monitoring and verification technologies. All wells, one for injection and two for observation, are equipped with smart casings (sensors behind casing, facing the rocks) containing a Distributed Temperature Sensing (DTS) and electrodes for Electrical Resistivity Tomography (ERT). The in-hole Gas Membrane Sensors (GMS) observed the arrival of tracers and CO2 with high temporal resolution. Geophysical monitoring includes Moving Source Profiling (MSP), Vertical Seismic Profiling (VSP), crosshole, star and 4-D seismic experiments. Numerical models are benchmarked via the monitoring results indicating a sufficient match between observation and prediction, at least for the arrival of CO2 at the first observation well. Downhole samples of brine showed changes in the fluid composition and biocenosis. First monitoring results indicate anisotropic flow of CO2 coinciding with the “on-time” arrival of CO2 at observation well one (Ktzi 200) and the later arrival at observation well two (Ktzi 202). A risk assessment was performed prior to the start of injection. After one year of operations about 18,000 t of CO2 were injected safely. 相似文献
242.
Anya Vollpracht Wolfgang Brameshuber 《Environmental science and pollution research international》2010,17(5):1177-1182
Objective
In this paper, results regarding the leaching of trace elements out of mineral building materials under irrigation are presented. 相似文献243.
Biomarkers and low-molecular weight polyaromatic compounds have been extensively studied for their fate in the environment. They are used for oil spill source identification and monitoring of weathering and degradation processes. However, in some cases, the absence or presence of very low concentration of such components restricts the access of information to spill source. Here we followed the resistance of high-molecular weight sulfur-containing aromatics to the simulated weathering condition of North Sea crude oil by ultra high-resolution Fourier transform ion cyclotron resonance mass spectrometry. The sulfur aromatics in North Sea crude having double bond equivalents (DBE) from 6 to 14 with a mass range 188-674 Da were less influenced even after 6 months artificial weathering. Moreover, the ratio of dibenzothiophenes (DBE 9)/naphthenodibenzothiophenes (DBE 10) was 1.30 and 1.36 in crude oil and 6 months weathered sample, respectively reflecting its weathering stability. It also showed some differences within other oils. Hence, this ratio can be used as a marker of the studied crude and accordingly may be applied for spilled oil source identification in such instances where the light components have already been lost due to environmental influences. 相似文献
244.
William L. Hare Wolfgang Cramer Michiel Schaeffer Antonella Battaglini Carlo C. Jaeger 《Regional Environmental Change》2011,11(1):1-17
This paper reviews scientific and gray literature addressing climate change vulnerability and adaptation in the Inuvialuit
Settlement Region (ISR) in the western Canadian Arctic. The review is structured using a vulnerability framework, and 420
documents related directly or indirectly to climate change are analyzed to provide insights on the current state of knowledge
on climate change vulnerability in the ISR as a basis for supporting future research and long-term adaptation planning in
the region. The literature documents evidence of climate change in the ISR which is compromising food security and health
status, limiting transportation access and travel routes to hunting grounds, and damaging municipal infrastructure. Adaptations
are being employed to manage changing conditions; however, many of the adaptations being undertaken are short term, ad-hoc,
and reactive in nature. Limited long-term strategic planning for climate change is being undertaken. Current climate change
risks are expected to continue in the future with further implications for communities but less is known about the adaptive
capacity of communities. This review identifies the importance of targeted vulnerability research that works closely with
community members and decision makers to understand the interactions between current and projected climate change and the
factors which condition vulnerability and influence adaptation. Research gaps are identified, and recommendations for advancing
adaptation planning are outlined. 相似文献
245.
246.
K. C. Stein Chemist J. J. Feenan Chemist G. P. Thompson Physical Science Aid J. F. Shultz Chemist L. J. E. Hofer R. B. Anderson 《Journal of the Air & Waste Management Association (1995)》2013,63(4):275-281
A simple practical scheme for prediction and control of short duration air pollution maxima from a single source is demonstrated for a particular source-site geometry. The method makes use of a number of traditional semi-empirical atmospheric turbulence and diffusion relations in a different application. The concepts stressed in the current example are: (1) the incorporation of interactions of high frequency turbulence and low frequency meandering of the wind into a concentration forecast and (2) the use of source-site geometry to simplify the practical problem as much as possible. 相似文献
247.
Wolfgang Schaaf Michael Elmer Anton Fischer Werner Gerwin Rossen Nenov Hans Pretzsch Stefan Seifert Susanne Winter Markus Klemens Zaplata 《Environmental monitoring and assessment》2013,185(7):5965-5986
The objective of this paper is to present observations, results from monitoring measurements, and preliminary conclusions about the development of patterns and structures during the first 5 years of development of an artificial catchment starting from point zero. We discuss the high relevance of initial system traits and external events for the system development and draw conclusions for further research. These investigations as part of a Collaborative Research Center, aim to disentangle and understand the feedback mechanisms and interrelationships of processes and their co-development with spatial and temporal structures and patterns by studying an initial, probably less complex ecosystem. Therefore, intensive measurements were carried out in the catchment with regard to the development of surface structures, hydrological patterns, vegetation dynamics, water chemistry, and element budgets. During the first 5 years, considerable changes within the catchment were observed. Both internal and external factors could be identified as driving forces for the formation of structures and patterns in the artificial catchment. Initial structures formed by the construction process and initial substrate characteristics were decisive for the distribution and flow of water. External factors like episodic events triggered erosion and dissection during this initial phase, promoted by the low vegetation cover, and the unconsolidated sandy substrate. The transformation of the initial geosystem into areas with evolving terrestrial or aquatic characteristics and from a very episodic to a more permanent stream network and discharge, together with the observed vegetation dynamics increased site diversity and heterogeneity with respect to water and nutrient availability and transformation processes compared with the more homogenous conditions at point zero. The processes and feedback mechanisms in the initial development of a new landscape may deviate in rates, intensity, and dominance from those known from mature ecosystems. It is therefore crucial to understand these early phases of ecosystem development and to disentangle the increasingly complex interactions between the evolving terrestrial and aquatic, biotic, and abiotic compartments of the system. Long-term monitoring of initial ecosystems may provide important data and parameters on processes and the crucial role of spatial and temporal structures and patterns to solve these problems. Artificially created catchments could be a suitable tool to study these initial developments at the landscape scale under known, designed, and defined boundary conditions. 相似文献
248.
Ashis Bhattacharjee Haradhan Mandal Madhusudan Roy Joachim Kusz Wolfgang Hofmeister 《Environmental monitoring and assessment》2013,185(10):8673-8683
This paper deals with the physical nature of the fly ashes obtained from two thermal power plants, situated in West Bengal, India. The fly ash samples are characterized by using comprehensive techniques with an emphasis on their ultrafine nature. The particle sizes of the samples are estimated using scanning electron microcopy (SEM) and found to lie within 0.18–5.90 μm. For morphology and compositional analysis, we also use SEM coupled with energy dispersive X-ray spectrometry. From X-ray study of the fly ashes the nature of conglomeration is seen to be crystalline, and the major components are mullite (Al6Si2O13) and quartz (SiO2). The magnetic measurement of the fly ash samples was carried out by SQUID magnetometer. 57Fe Mössbauer spectra are obtained using a conventional constant-acceleration spectrometer with a 57Co/Rh Mössbauer source. The hyperfine parameters obtained, in general, support the findings as made from XRD analysis and provide a quantitative measure of different iron ions present in the samples. The paper presents experimental data on the physical aspects of the fly ash samples of the thermal power plants which comprise coarse, fine, and ultrafine magnetic particulate materials and attempts to provide an exhaustive analysis. 相似文献
249.
Bernd Lengers Inga Schiefler Wolfgang Büscher 《Environmental monitoring and assessment》2013,185(12):9751-9762
The overall measurement of farm level greenhouse gas (GHG) emissions in dairy production is not feasible, from either an engineering or administrative point of view. Instead, computational model systems are used to generate emission inventories, demanding a validation by measurement data. This paper tests the GHG calculation of the dairy farm-level optimization model DAIRYDYN, including methane (CH4) from enteric fermentation and managed manure. The model involves four emission calculation procedures (indicators), differing in the aggregation level of relevant input variables. The corresponding emission factors used by the indicators range from default per cow (activity level) emissions up to emission factors based on feed intake, manure amount, and milk production intensity. For validation of the CH4 accounting of the model, 1-year CH4 measurements of an experimental free-stall dairy farm in Germany are compared to model simulation results. An advantage of this interdisciplinary study is given by the correspondence of the model parameterization and simulation horizon with the experimental farm’s characteristics and measurement period. The results clarify that modeled emission inventories (2,898, 4,637, 4,247, and 3,600 kg CO2-eq. cow?1 year?1) lead to more or less good approximations of online measurements (average 3,845 kg CO2-eq. cow?1 year?1 (±275 owing to manure management)) depending on the indicator utilized. The more farm-specific characteristics are used by the GHG indicator; the lower is the bias of the modeled emissions. Results underline that an accurate emission calculation procedure should capture differences in energy intake, owing to milk production intensity as well as manure storage time. Despite the differences between indicator estimates, the deviation of modeled GHGs using detailed indicators in DAIRYDYN from on-farm measurements is relatively low (between ?6.4 % and 10.5 %), compared with findings from the literature. 相似文献
250.
Birth sex ratios in toque macaques and other mammals: integrating the effects of maternal condition and competition 总被引:2,自引:0,他引:2
Wolfgang P. J. Dittus 《Behavioral ecology and sociobiology》1998,44(3):149-160
Mammalian life histories suggest that maternal body condition and social dominance (a measure of resource-holding potential)
influence the physical and social development of offspring, and thereby their reproductive success. Predictably, a mother
should produce that sex of offspring which contributes most to her fitness (as measured by the number of her grandchildren)
and that she is best able to raise within the constraints imposed by her condition, social rank, and environment. Such combined
effects were investigated by monitoring variations in body condition (weight) and behavior of female toque macaques, Macaca sinica of Sri Lanka, in a changing forest environment over 18 years. Maternal rank, by itself, had no influence on offspring sex,
but did affect maternal body condition. The combined effects of rank and condition indicated the following: mothers in robust
condition bore more sons, whereas those in moderate condition bore more daughters, but both effects were expressed most strongly
among mothers of high rank. Where the consequences of low rank were felt most acutely, as shown by poor condition, mothers
underproduced daughters. Environmental quality directly influenced rank and condition interactions, and thus sex ratios. These
relationships, and data from other mammals suggest an empirically and theoretically consistent pattern of sex allocation in
mammals. New predictions integrate effects, proposed by Trivers and Willard, that are rooted in male mate competition, which
is universal among polygynous mammals, with those of local resource competition (and/or female reproductive competition),
which are not universal and differ in intensity between the socioecologies and local environments of different species.
Received: 30 May 1998 / Accepted after revision: 29 August 1998 相似文献