Sediment penetration of Amoco Cadiz oil,potential for future release,and toxicity

Weathering states of oil ranging from sheen oil to mousse have significant effects during oil stranding on oil-water and oil-sediment interaction. Observations of oiled sandy beaches suggest two mechanisms of beach contamination—general penetration and contamination of beach substrate by films of sheen oil (probably partially emulsified), and secondly the burial of discrete layers of mousse. Depending on timing of oiling with respect to beach dynamics large amounts of stranded oil can be accommodated within beach sediments. These then become available for later long-term release.Acute lethal toxicity of stranded Amoco Cadiz oil is intermediate to Bunker C and Kuwait crude. Simulated weathering studies suggest that there may be some increase in toxicity with weathering.     

The Amoco Cadiz oil spill

This report gives a preliminary account of the events surrounding the wreck of the Amoco Cadiz on the Brittany coast in March, which caused the most massive oil pollution on record.     

Convoluta roscoffensis and the Amoco Cadiz oil spill

The intertidal symbiotic flatworm, Convoluta roscoffensis, was found on the sandy beach at Dunes de Ste. Marguerite 4 months after heavy pollution by oil from the Amoco Cadiz. Seven of the nine sites recorded 2 years previously had colonies of worms. The colonies were fewer and smaller, but densities within colonies were unchanged.     

The Amoco Cadiz oil spill—At a glance

The tanker Amoco Cadiz grounded close to Aber Wrac'h in Brittany, France, on March 1978. Graphs are presented, showing the fate of the oil, the recovery of the biota and the social impacts after the grounding. Visual insepction in 1983 showed that there are still nuisance amounts of oil, and the biotic recovery is far from being complete with respect to species distribution.     

Impact of Amoco Cadiz oil spill on intertidal and sublittoral meiofauna

Changes of meiofauna densities (nematodes and harpacticoid copepods) were studied in intertidal and sublittoral fine sand heavily polluted by the Amoco Cadiz oil spill. A general decrease in the nematode abundance was obvious in intertidal sand seven months after the pollution in spite of the occurrence of the natural spring bloom. No changes in the nematode and copepod densities could be detected in sublittoral sand. Comparisons with the pre-pollution data show, however, a significant decrease in the nematode diversity, mainly due to the increase of some limited dominant species after pollution.     

Abnormal development of Dentalium due to the Amoco Cadiz oil spill

A comparison was made between the development of Dentalium eggs, spawned by animals, collected before and after the Amoco Cadiz oil spill. Development of eggs from animals collected before the oil spill was significantly better than development of eggs from animals collected after the oil spill. It is suggested that development is affected by oil hydrocarbons, accumulated during oogenesis in the lipidrich phases of the oocytes.     

Long term monitoring of meiofauna densities after the Amoco Cadiz oil spill

Long term temporal variations in nematode and copepod densities were monitored in the upper and lower part of the Bay of Morlaix (West Channel), which was heavily contaminated by the 1978 Amoco Cadiz oil spill. Deseasonalization of abundance data allowed estimates to be made of the different components, namely the annual and seasonal trends and the residue. Reduced nematode abundance was long lasting in both types of sediment investigated: it appeared to be a gradual decrease in sublittoral sand but there was a dramatic reduction in estuarine mud 2 years after disturbance. Copepod variability, however, was related to seasonal factors.     

Effects of chitin on microbial emulsification, mineralization potential, and toxicity of bunker C fuel oil

Bunker C, one of the most frequently spilled petroleum products in the US, is difficult to remove from oiled surfaces and is relatively recalcitrant to biodegradation; therefore, emulsification and biodegradability must be optimized before bioremediation can be considered a viable treatment option. Sand from a freshly oiled beach near Dutch Harbor, Alaska, was incubated at 10 degrees C with nutrients (Bushnell-Haas (BH)) or nutrients with crab shell chitin (BH-C). BH-C amendment resulted in greater numbers of bunker C emulsifiers and greater mineralization potentials for hexadecane, phenanthrene, and fluorene than with BH only. Compared to BH alone, mineralization potentials for bunker C also were higher in BH-C, with an estimated 8% of fuel oil mineralized after 6 weeks. Microbially emulsified oil was more toxic than in uninoculated controls (p < 0.05) as measured by Microtox assays. However, toxicity was significantly lower in BH-C than BH after 4 and 6 weeks incubation (p < 0.05).     

Sediment toxicity and the distribution of amphipods in Commencement bay,Washington, USA

The toxicity of 175 sediment samples from Commencement Bay, Washington, was measured by the survival of marine infaunal amphipods (Rhepoxynius abronius) during ten-day exposure to test sediment. Survival was high in sediment from offshore, deeper parts of the Bay, including two designated dredge material disposal sites. Within each of the major industrialized waterways there was a wide range in amphipod survival. Both acutely toxic and relatively nontoxic samples were collected from various areas within the Hylebos, Blair, Sitcum and City Waterways. Habitat differences, sedimentation rates, proximity to contaminant sources and sinks, and disruption of the seabed by prop scour and dredging could contribute to this variation in toxicity. Community structure data show a correlation between amphipod distribution and sediment toxicity, with lower amphipod density and species richness in the waterways than in the deeper part of the Bay. Phoxocephalid amphipods, a family that includes the bioassay species, were ubiquitous in the deeper Bay, but absent from the waterways. This correlation between laboratory and field results indicates the ecological relevance of the sediment bioassay.     

中国油气页岩分布与存储潜能和前景分析

基于当今化石油气能源的需求还在扩展,它的紧缺势态波及全球,而我国的确需要更多的页岩油气.为此,非常规油气能源,特别是页岩油气的勘探、开发和利用就必然地提到社会进步和经济发展的议程上,并得到世界各个国家的高度重视.因此,页岩油气现已成为我国能源界和科技界及政府部门的热门话题.在经过了一段时间的"热炒"和依据尚不充分的评估后,本文通过对中外有关资料的分析和讨论认为:1)必须在了解世界各国、特别是北美页岩油气赋存与开发的条件下,认识我国页岩的分布状态和页岩油气潜能;2)在理解其它国家页岩属性、页岩油气的前景和勘查及储存背景下,在我国较全面的进行页岩和页岩油气存储的勘探和对其进行要素匹配,并选择远景好的典型地区进行示范研究与探索;3)集理念与实践综合研究制定页岩油气在我国的发展方案和路线图.     

近地小行星探测目标选择

从数以万计的近地小行星(NEAs)中选择探测目标,是一项非常重要的工作.选择小行星时需要考虑的主要问题是:NEAs的轨道参数、自旋周期、大小、科学价值、表面特征以及到达NEAs的时间.本文采用排除法从众多近地小行星中确定候选者,并根据科学目标的要求确定最终探测目标.     

A Sediment Quality Triad: Measures of sediment contamination,toxicity and infaunal community composition in Puget Sound

Increasing emphasis is being placed upon chemical analyses of sediments to determine the distribution and concentration of toxic chemicals in marine and aquatic environments. The resulting data are often used to characterize chemical accumulations, including delineation of ‘hotspots’. These data alone, however, provide no information regarding the possible biological significance of these accumulations. Direct biological testing is needed. the use of a Sediment Quality Triad (chemical, bioassay and infauna) of measurements is advocated here by the authors. The purpose of this study was to determine the correspondence among measures of the three components of the Triad, using available data from several studies of Puget Sound. Good overall correspondence among the three components of the Triad was observed, based upon a comparison of average values from urban and rural portions of the Sound. However, based upon comparisons of data on a station-by-station basis the chemical data alone were not always reliable indicators (and, therefore, predictors) of biological effects. Hence, the importance and usefulness of the Triad was substantiated.     

河南省孟州市石庄生油岩特点及潜力分析

河南省孟州市石庄位于济源盆地东南缘,地层属华北地层区山西分区太行山小区。出露的主要地层有中生界三叠系、新生界第三系、第四系。中生代经历了长期陆相湖盆沉积阶段,岩石中有机物含量高。所以该区中生界地层一直作为煤系地层并进行了煤矿资源的勘查工作。本文通过对中生界上三叠统谭庄组的灰黑色岩系取样分析研究,认为该区上三叠统谭庄组为一套含生油岩地层,是济源盆地东侧生油区。在具备一定的运移、储集及盖层等地质条件下可以形成一定规模的油气资源。为今后在河南西北济源盆地寻找油气资源提供了启示。     

Sediment detachment in piping-prone soils: Cohesion sources and potential weakening mechanisms

Soil piping is a widespread land degradation process that may lead to gully formation. However, the processes involved in sediment detachment from soil pipe walls have not been well studied, although their recognition is a crucial step to protect soils from piping erosion. This study aims to recognize the factors affecting cohesion and to identify the mechanisms which are likely to be responsible for the disintegration of soil. The study has been conducted in mid-altitude mountains under a temperate climate (the Bieszczady Mountains, the Carpathians, SE Poland). The research was based on the detailed field and laboratory analyses of morphology, and the physical and chemical properties of soil profiles with and without soil pipes. Moreover, experiments with flooding the undisturbed soil samples using different solutions (deionized water, ammonium oxalate, dithionate citrate, 35% hydrochloric acid and 30% hydrogen peroxide) were conducted in order to check the role of air slaking, the removal of soil organic carbon (SOC), and Fe and Al oxides on sediment detachment. The obtained results have confirmed that soil pipes develop in quite cohesive soils (silt loams), which allow the formation and maintenance of pipes with a diameter up to 30 cm. Soil cohesion, and thus susceptibility to piping, are impacted by the content of major oxides, soil particle size distribution, biological activity and porosity. The tested soils affected by piping erosion have a lower content of Al₂O₃ and Fe₂O₃, and free Fe (Fe_(DCB)), lower clay content, higher biological activity (more roots and animal burrows), higher porosity, and more and larger pores than the profile without soil pipes. The experiments have indicated that especially SOC along with Fe and Al oxides are an important cohesion source in the study area. This suggests that the removal of SOC, and Fe and Al oxides may weaken and disintegrate aggregates in soil pipes. Further study of soil leaching and tensile strength will broaden understanding of which chemical processes control where pipes will develop in other cohesive piping-prone soils. © 2020 John Wiley & Sons, Ltd.     

Potential for photoenhanced toxicity of spilled oil in Prince William Sound and Gulf of Alaska waters

Photoenhanced toxicity is the increase in the toxicity of a chemical in the presence of ultraviolet light (UV) compared to a standard laboratory test conducted with fluorescent lighting (minimal UV). Oil products, weathered oil, and specific polycyclic aromatic compounds present in oil are 2 to greater than 1000 times more toxic in the presence of UV. The photoenhanced toxicity of oil to fish and aquatic invertebrates appears to occur through a process of photosensitization, rather than photomodification of the aqueous phase oil. In photosensitization, the bioaccumulated chemical transfers light energy to other molecules causing toxicity through tissue damage rather than a narcosis mechanism. The available evidence indicates that phototoxic components of oil are specific 3-5 ring polycyclic aromatic hydrocarbons (PAHs) and heterocycles. Determinants of photoenhanced toxicity include the extent of oil bioaccumulation in aquatic organisms and the spectra and intensity of UV exposure. No studies have specifically investigated the photoenhanced toxicity of spilled oil in Alaska waters. Although there are substantial uncertainties, the results of this evaluation indicate there is potential for photoenhanced toxicity of spilled oil in Prince William Sound and the Gulf of Alaska. The potential hazard of photoenhanced toxicity may be greatest for embryo and larval stages of aquatic organisms that are relatively translucent to UV and inhabit the photic zone of the water column and intertidal areas. Photoenhanced toxicity should be considered in oil spill response because the spatial and temporal extent of injury to aquatic organisms may be underestimated if based on standard laboratory bioassays and existing toxicity databases. Additionally, the choice of counter measures and oil removal operations may influence the degree of photoenhanced toxicity.