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1.
The architecture of macrofaunal burrows and the total area of the sediment-water interface created by biogenic structure were
investigated in the Donggeomdo tidal flat on the west coast of Korea. Resin casting methods were applied to recover burrows
of four dominant species, Macrophthalmus japonicus, Cleistostoma dilatatum, Perinereis aibuhitensis, and Periserrula leucophryna,
and whole burrows within the casting area at three sites in different tidal levels.P. leucophryna excavated the largest burrow in terms of a surface area among them. In the case of whole burrow casting, the space occupied
by the biogenic structure was extended into deeper and expanded more greatly at the higher tidal level. In the uppermost flat,
the burrow wall surface area within sediment was more extensive than the sediment surface area. Increased oxygen supply through
the extended interface could enhance the degradation rates of organic carbon and also change the pathways of degradation.
Quantifying the relationship between the extended interface and mineralization rate and pathway requires more extensive study. 相似文献
2.
Pristane (2,6,10,14 -tetramethylpentadecane) occurs ubiquitously in the marine environment. This hydrocarbon may be of biogenic or petrogenic origin.1 Recently it has been shown that residual amounts of this branched alkane increased in marine organisms after an oil spill.2,3 The lack of data on the fate of pristane in fish, added with the fact that this compound was considered by some authors as a non-metabolisable substance in vertebrates, including man,4 led us to investigate the capability of fish to metabolise pristane. In this study, urinary and fecal excretion, tissue distribution and metabolism of 3H-pristane were analysed in Salmo gairdneri R. after a single intragastric dose. In addition to unchanged hydrocarbon, various labelled compounds have been isolated and identified in liver, bile, faeces, urine and surrounding water, demonstrating that pristane was first oxidised to alcohols (pristanol and pristane-diol) and to acid (pristanic acid). The elimination of these compounds occurred in the form of conjugated products (primarily glucuronides) as well as free metabolites. 相似文献
3.
Meisina C. Bonì R. Bozzoni F. Conca D. Perotti Cesare Persichillo Pina Lai C. G. 《Bulletin of Earthquake Engineering》2022,20(11):5601-5632
Bulletin of Earthquake Engineering - Mapping the susceptibility of earthquake-induced soil liquefaction at the continental scale is a challenge. Susceptibility of soils to liquefaction is the... 相似文献
4.
Simone Fiaschi Serena Tessitore Roberta Bonì Diego Di Martire Vladimiro Achilli Sven Borgstrom 《地理信息系统科学与遥感》2017,54(3):305-328
Land subsidence due to underground resources exploitation is a well-known problem that affects many cities in the world, especially the ones located along the coastal areas where the combined effect of subsidence and sea level rise increases the flooding risk. In this study, 25 years of land subsidence affecting the Municipality of Ravenna (Italy) are monitored using Advanced Differential Interferometric Synthetic Aperture Radar (A-DInSAR) techniques. In particular, the exploitation of the new Sentinel-1A SAR data allowed us to extend the monitoring period till 2016, giving a better understanding of the temporal evolution of the phenomenon in the area. Two statistical approaches are applied to fully exploit the informative potential of the A-DInSAR results in a fast and systematic way. Thanks to the applied analyses, we described the behavior of the subsidence during the monitored period along with the relationship between the occurrence of the displacement and its main driving factors. 相似文献
5.
To determine the existence of p-nitrophenol (PNP)-lowering bacteria in intestine of Japanese coastal fish, the gastro-intestinal contents were incubated in Brain Heart Infusion (BHI) broth and minimal medium (MM) broths containing 1 mmol/L PNP at 30 °C for 7 days. Among 26 samples of 19 fish species, 17 samples showed a decrease in PNP of 0.5-0.8 mmol/L in BHI broth, but no decrease was shown in MM broth. Eighteen PNP-lowering bacterial strains were isolated from four fishes. All of the strains were identified as Lactococcus lactis subsp. lactis. Three L. lactis strains JS1-3 isolated from Japanese seabass Lateolabrax japonicus showed the highest PNP-lowering activity (0.44 mmol/L). Optimum temperature and pH for the growth and PNP decreasing corresponded with the marine environment. These results suggested that marine fishes have PNP decreasing bacteria in their intestine. These bacteria might protect host fish from toxicities of PNP and PNP related compounds. 相似文献
6.
Lucina Hernndez Robert R. Parmenter John W. Dewitt David C. Lightfoot John W. Laundr 《Journal of Arid Environments》2002,51(4):613
With 7 years data on coyote prey use and availability, we tested three predictions based on optimal foraging: (1) the proportion eaten of the most profitable item is constant regardless of availability, (2) under a constant density of higher ranked prey, there is no relationship between the proportion eaten of low profitability items and their density, (3) the ratio of number consumed to availability for the highest ranking prey item should be negatively related to availability. We tested these predictions with regression analyses. We found no significant linear relationship between lagomorph availability and use. There was no significant linear relationship between percent frequency of occurrence of rodents nor arthropods and their respective availabilities for two levels of availability of lagomorphs. We found a significant negative relationship between number consumed/number available to availability for lagomorphs but not for rodents nor arthropods. The results supported the three predictions and we concluded that coyotes are foraging optimally. 相似文献
7.
8.
Tao Liu Amr Abd-Elrahman Bon Dewitt Scot Smith Jon Morton Victor L. Wilhelm 《地理信息系统科学与遥感》2019,56(1):130-159
Unmanned Aerial Systems (UASs) have the potential to provide multi-view data, but the approaches used to extract the multi-view data from UAS and investigation of their use in image classification are currently unavailable in publications to our best knowledge. This study presents a method that combines collinearity equations and a two-phase optimization procedure to automatically project a point from real world coordinate system of an orthoimage to UAS image coordinate system (row and column numbers) to be used in multi-view data extraction. The results show average errors for the computed UAS column and row numbers were 1.6 and 1.8 pixels respectively evaluated with leave-one-out method. Based on this algorithm, it’s also for the first time that object-based multi-view data were extracted and presented, and the potential of using the multi-view data to aid Geographic Object-Based Image Analysis(GEOBIA) through bidirectional reflectance distribution function (BRDF) modelling was evaluated with two representatives of BRDFs, the Rahman-Pinty-Verstraete(RPV) and Ross-Thick-LiSparse (RTLS). Our results indicate the RPV model tends to overestimate the bidirectional reflectance for land cover types with high reflectance, while perform well for those with relatively low reflectance in our study area. To test the impact of using multi-view data on image classification, we extracted parameters from BRDF models and used these parameters as object features for object-based classification. The 10-fold cross validation results show that the 3-parameter RTLS significantly improved overall accuracy compared to the classifications relying only on the orthoimage features, while other BRDF models did not show significant improvements, raising the needs to develop new methods to better utilize the multi-view information in GEOIBA in the future. 相似文献
9.
Assuming that the figures of the central icon of the Mithraic cult – the scene of tauroctony (bull slaying) – represent equatorial constellations at the time when the spring equinox was placed somewhere between Taurus and Aries, it is difficult to explain why some equatorial constellations (Orion and Libra) were not included in the Mithraic icons A simulation of the sky at the times in which the spring equinox was in the constellation of Taurus, only a small area of spring equinox positions permits to exclude these two constellations, with all other representations of equatorial constellations (Taurus, Canis Minor, Hydra, Crater, Corvus, Scorpio) included. These positions of the spring equinox occurred at the beginning of the age of Taurus, and included Gemini as an equatorial constellation. Two of the main figures in the Mithraic icons are two identical figures, usually represented on the each side of the bull, wearing phrygian caps and holding torches. Their names, Cautes and Cautopates, and their looks may indicate that they represent the constellation of Gemini. In that case the main icon of Mithraic religion could represent an event that happened around 4000 BC, when the spring equinox entered the constellation of Taurus. Also, this position of equator contains Perseus as an equatorial constellation. Ulansey suggested that the god Mithras is identified with the constellation Perseus. In that case, all figures in the main scene would be equatorial constellations. 相似文献
10.
This paper proposes and tests a method of producing macrofauna habitat potential maps based on a weights-of-evidence model (a probabilistic approach) for the Hwangdo tidal flat, Korea. Samples of macrobenthos were collected during field work, and we considered five mollusca species for habitat mapping. A weights-of-evidence model was used to calculate the relative weights of 10 control factors that affect the macrobenthos habitat. The control factors were compiled as a spatial database from remotely sensed data combined with GIS analysis. The relative weight of each factor was integrated as a species potential index (SPI), which produced habitat potential maps. The maps were compared with the surveyed habitat locations, revealing a strong correlation between the potential maps and species locations. The combination of a GIS-based weights-of-evidence model and remote sensing techniques is an effective method in determining areas of macrobenthos habitat potential in a tidal flat setting. 相似文献