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81.
82.
Simon Rozalyn A. Ranasinghe Purnika Damindi Barazanji Nawroz Jungeström Malin Bergman Xu Jie Bednarska Olga Serrander Lena Engström Maria Bazylinski Dennis A. Keita Åsa V. Walter Susanna 《中国海洋湖沼学报》2021,39(6):2044-2052
Journal of Oceanology and Limnology - Magnetotactic bacteria (MTB), ubiquitous in soil and fresh and saltwater sources have been identified in the microbiome of humans and many animals. MTB... 相似文献
83.
For the first time, the structure of the meiobenthos community and marine nematodes in particular was investigated in the
different intertidal zones of Jeju Island (South Sea of Korea). A relationship was found between the density of meiobenthic
communities and the type of the bottom sediment. In addition, in the silty sediments, nematodes were dominant, while in the
sandy sediments harpacticoids and ostracods were dominant groups. Sixty eight species belonging to 60 genera and 19 families
of nematodes were found in the whole area. Four different nematode taxocenosis were distinguished using a cluster analysis.
Dominant feeding groups were omnivores (2B) and epistratum-feeders (2A). The highest number of non-selective deposit-feeders
(1B) was detected in the lagoon with the bottom silty sediments. 相似文献
84.
Russell S. Crosbie Trevor Pickett Freddie S. Mpelasoka Geoff Hodgson Stephen P. Charles Olga V. Barron 《Climatic change》2013,117(1-2):41-53
This study used 16 Global Climate Models and three global warming scenarios to make projections of recharge under a 2050 climate for the entire Australian continent at a 0.05° grid resolution. The results from these 48 future climate variants have been fitted to a probability distribution to enable the results to be summarised and uncertainty quantified. The median results project a reduction in recharge across the west, centre and south of Australia and an increase in recharge across the north and a small area in the east of the continent. The range of results is quite large and for large parts of the continent encompasses both increases and decreases in recharge. This makes it difficult to utilise for water resources management so the results have been analysed with a risk analysis framework; this enables the future projections for groundwater recharge to be communicated to water managers in terms of likelihood and consequence of a reduction in recharge. This highlights an important message for water resource managers that in most areas of Australia they will be making decisions on water allocations under considerable uncertainty as to the direction and magnitude of recharge change under a future climate and that this uncertainty may be irreducible. 相似文献
85.
An attempt to detect the finest white-light coronal features observed with a large optical telescope was made at the July 11, 1991 Solar Total Eclipse. A few selected results taken from the video-CCD high speed observations obtained at the prime focus of the Canada-France-Hawaï-Telescope (CFHT) with a red coronal interference filter are presented. The smallest (sub-arsec) detected and/or resolved coronal features are shown. The methods that were used to extract them from the noisy and seeing-limited images taken from video frames are described. 相似文献
86.
87.
Marina KOLPAKOVA Stepan SHVARTSEV Vitalyi ISUPOV Sodov ARIUNBILEG Alexander VLADIMIROV Olga GASKOVA 《《地质学报》英文版》2014,88(Z1):142-144
正All the lakes are accumulative systems for the various chemical elements.However,the ratios of the elements in different lake types are very different.It is generally accepted that the composition of lake water determined by 相似文献
88.
Ludger Timmen Olga Gitlein Volker Klemann Detlef Wolf 《Pure and Applied Geophysics》2012,169(8):1331-1342
The Nordic countries Norway, Sweden, Finland and Denmark are a key study region for research of glacial isostasy. In addition, such research offers a unique opportunity for absolute gravimetry to show its capability as a geodetic tool for geophysical research. Within a multi-national cooperation, annual absolute gravity measurements have been performed in Fennoscandia by IfE since 2003. For the Hanover gravimeter FG5-220, overall accuracy of ±30?nm/s2 is indicated for a single station determination. First results of linear gravity changes are derived for ten stations in the central and southern part of the uplift area. Comparing with the rates predicted by glacial rebound modelling, the gravity trends of the absolute measurements differ by 3.8?nm/s2 per year (root-mean-square discrepancy) from the uplift model. The mean difference between observed and predicted rates is 0.8?nm/s2 per year only. A proportionality factor of ?1.63?±?0.20?nm/s2 per mm has been obtained, which describes the mean ratio between the observational gravity and height rates. 相似文献
89.
We study the feasibility of the application of an indirect EM geothermometer, developed recently, to the temperature extrapolation in depth using magnetotelluric data collected in the seismically active northern Tien Shan faulted area (Bishkek Geodynamic Test Site, Kyrgyzstan) and Hengill geothermal zone (Iceland). The approach used is based on the artificial neural network technique, which does not imply the prior knowledge of the electrical conductivity mechanisms on the one hand and provides temperature estimates based on the analysis of the implicit conductivity-temperature relations, on the other.
The samples for neuronet teaching consisted in the well temperature records and electrical conductivity values determined for the same depths from the magnetotelluric data measured in the vicinities of eight boreholes in each testing area. The testing of the taught neuronets was carried out using the temperature records not involved in the teaching process. The results indicate that the temperature extrapolation accuracy essentially depends on the ratio between the well length and the extrapolation depth. In particular, in extrapolation to a depth twice as large as the well depth the relative error is 5–6% and in case of threefold excess, the error is around 20%. This result makes it possible to increase significantly the depth of indirect temperature estimation in the Earth's interior (in particular, for geothermal exploration) based on the available temperature logs.
The practical application of an indirect electromagnetic geothermometer could provide the following facilities: 1) more exact temperature estimation in the extrapolation mode; 2) remote temperature estimates in the boreholes in areas characterized by extreme conditions for conventional geothermometers. 相似文献
The samples for neuronet teaching consisted in the well temperature records and electrical conductivity values determined for the same depths from the magnetotelluric data measured in the vicinities of eight boreholes in each testing area. The testing of the taught neuronets was carried out using the temperature records not involved in the teaching process. The results indicate that the temperature extrapolation accuracy essentially depends on the ratio between the well length and the extrapolation depth. In particular, in extrapolation to a depth twice as large as the well depth the relative error is 5–6% and in case of threefold excess, the error is around 20%. This result makes it possible to increase significantly the depth of indirect temperature estimation in the Earth's interior (in particular, for geothermal exploration) based on the available temperature logs.
The practical application of an indirect electromagnetic geothermometer could provide the following facilities: 1) more exact temperature estimation in the extrapolation mode; 2) remote temperature estimates in the boreholes in areas characterized by extreme conditions for conventional geothermometers. 相似文献
90.
Johanna K. Spiegel Nina Buchmann Olga L. Mayol-Bracero Luis A. Cuadra-Rodriguez Carlos J. Valle Díaz Kimberly A. Prather Stephan Mertes Werner Eugster 《Pure and Applied Geophysics》2014,171(9):2443-2459
We investigated cloud properties of warm clouds in a tropical montane cloud forest at Pico del Este (1,051 m a.s.l.) in the northeastern part of Puerto Rico to address the question of whether cloud properties in the Caribbean could potentially be affected by African dust transported across the Atlantic Ocean. We analyzed data collected during 12 days in July 2011. Cloud droplet size spectra were measured using the FM-100 fog droplet spectrometer that measured droplet size distributions in the range from 2 to 49 µm, primarily during fog events. The droplet size spectra revealed a bimodal structure, with the first peak (D < 6 µm) being more pronounced in terms of droplet number concentrations, whereas the second peak (10 µm < D < 20 µm) was found to be the one relevant for total liquid water content (LWC) of the cloud. We identified three major clusters of characteristic droplet size spectra by means of hierarchical clustering. All clusters differed significantly from each other in droplet number concentration ( \(N_{\rm tot}\) ), effective diameter (ED), and median volume diameter (MVD). For the cluster comprising the largest droplets and the lowest droplet number concentrations, we found evidence of inhomogeneous mixing in the cloud. Contrastingly, the other two clusters revealed microphysical behavior, which could be expected under homogeneous mixing conditions. For those conditions, an increase in cloud condensation nuclei—e.g., from processed African dust transported to the site—is supposed to lead to an increased droplet concentration. In fact, one of these two clusters showed a clear shift of cloud droplet size spectra towards smaller droplet diameters. Since this cluster occurred during periods with strong evidence for the presence of long-range transported African dust, we hypothesize a link between the observed dust episodes and cloud characteristics in the Caribbean at our site, which is similar to the anthropogenic aerosol indirect effect. 相似文献