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171.
广西的一些重要泥盆系剖面如横县六景、环江北山、永福凤凰和军屯、象州大乐、罗城龙岸,融安古当等都有明显的白云岩化。1984年作者之一得到部、局批准在广西石油队、区调队、科研所野外工作的基础上选取了256块标本带到英国作进一步研究(图1)。 在显微镜鉴定的基础上,对其中沉积成岩环境特别有意义的82块标本,在伯明翰大学进行了计点的统计分析、阴极发光分析、X光衍射分析。电子探针分析、电子显微镜扫描、背散分析、以及原子吸收光谱分析和酸不溶残余物分析;在英国地质调查所伦敦实验室做 相似文献
172.
Schaffelke B Carleton J Skuza M Zagorskis I Furnas MJ 《Marine pollution bulletin》2012,65(4-9):249-260
Coastal and inshore areas of the Great Barrier Reef lagoon receive substantial amounts of material from adjacent developed catchments, which can affect the ecological integrity of coral reefs and other inshore ecosystems. A 5-year water quality monitoring dataset provides a 'base range' of water quality conditions for the inshore GBR lagoon and illustrates the considerable temporal and spatial variability in this system. Typical at many sites were high turbidity levels and elevated chlorophyll a and phosphorus concentrations, especially close to river mouths. Water quality variability was mainly driven by seasonal processes such as river floods and sporadic wind-driven resuspension as well as by regional differences such as land use. Extreme events, such as floods, caused large and sustained increases in water quality variables. Given the highly variable climate in the GBR region, long-term monitoring of marine water quality will be essential to detect future changes due to improved catchment management. 相似文献
173.
Tatiana V. DONSKAYA Dmitry P. GLADKOCHUB Richard E. ERNST Sergei A. PISAREVSKY Anatoliy M. MAZUKABZOV Ulf S?DERLUND Michael T.D. WINGATE Michael A. HAMILTON Elena I. DEMONTEROVA 《《地质学报》英文版》2016,90(Z1):125-126
正Several generations of mafic dyke swarms of different ages and geochemical characteristics cut Precambrian rocks of the southern part of the Siberian craton(Irkutsk Promontory).Each generation of dykes is related to a 相似文献
174.
KHARUK Viacheslav I. PETROV Il'ya A. GOLYUKOV Alexey S. DVINSKAYA Maria L. IM Sergei T. SHUSHPANOV Alexander S. 《山地科学学报》2023,(1):101-114
Climate-driven changes in the thermal and moisture regimes may variously influence different tree species growth and ranges. We hypothesize that drought resistant Siberian larch(Larix sibirica Ledeb.) and precipitation-sensitive Siberian pine(Pinus sibirica Du Tour) responded differently to climate change along the elevational thermal and precipitation gradients. We studied the influence of air temperature, precipitation, soil moisture, and atmospheric drought(indicated by the drought index SPEI... 相似文献
175.
Restrictions on the use of tributyltin (TBT) in aquaculture and on boats in coastal regions, except for ocean-going vessels, have been in place in Japan since 1990 due to the strong toxic effects of TBT on marine organisms. However, TBT pollution along the Japanese coasts has been reported after this legislation was enacted. In order to elucidate the present status of contamination by butyltin (BT) compounds, we measured the levels of BTs [monobutyltin (MBT), dibutyltin (DBT) and TBT] in seawater and Caprella spp. samples obtained from the western part of Seto Inland Sea, Uwa Sea and Uranouchi Bay in western Japan during March to September, 2001. Butyltins were detected in more than 90% of the seawater samples (n = 59), with average concentrations of 8.2 ± 9.2 (SD) ng MBT L−1, 3.3 ± 3.0 ng DBT L−1 and 9.0 ± 7.0 ng TBT L−1. Among 41 stations situated on coastal lines, a sufficient number of Caprella organisms for chemical analysis could be collected from only 16 stations. The butyltin concentrations in seawater and Caprella samples from Uwa Sea and Uranouchi Bay, in which the dominant industry in both waters is aquaculture, showed significantly higher than or no significant differences from those samples from the western part of Seto Inland Sea, a major heavy-industry area in Japan. As the TBT concentration in seawater increased, the number of Caprella organisms collected decreased. The mean TBT concentration among the seawater samples was above the estimated lowest observable effect concentration (LOEC) that reduces the survival rate of Caprella danilevskii. Thus, the present study indicates that TBT is still a potential ecological hazard to the survival of marine invertebrates inhabiting coasts along western Japan, even 11 years after the partial ban on TBT usage was implemented. 相似文献
176.
Marigómez I Soto M Cancio I Orbea A Garmendia L Cajaraville MP 《Marine pollution bulletin》2006,53(5-7):287-304
In order to assess the biological effects of the Prestige oil spill (POS), mussels (Mytilus galloprovincialis), European hake (Merluccius merluccius) and European anchovy (Engraulis encrasicolus) were sampled between April and September 2003 in various geographical areas of Bay of Biscay: Galicia, Central Cantabrian and East Cantabrian. In mussels, several cell and tissue biomarkers were measured: peroxisome proliferation as induction of acyl-CoA oxidase (AOX) activity, lysosomal responses as changes in the structure (lysosomal volume density, V(V(L)), surface-to-volume ratio, S/V(L), and numerical density, N(V(L))) and in membrane stability (labilization period, LP), cell type replacement as relative proportion of basophilic cells (volume density of basophilic cells, V(V(BAS))) in digestive gland epithelium, and changes in the morphology of digestive alveoli as mean luminal radius to mean epithelial thickness (MLR/MET). Additionally, flesh condition index (FCI) and gonad index (GI) were measured as supporting parameters. In hake and anchovy, liver histopathology was examined to determine the prevalence of parasites, melanomacrophage centers, non-specific lesions (inflammatory changes, atrophy, necrosis, apoptosis), early non-neoplastic toxicopathic lesions (i.e., hepatocellular nuclear polymorphism), foci of cellular alteration, benign and malignant neoplasms. In mussels, AOX induction was noticeable in April except in Galicia. LP values were low in all the geographical areas studied, indicating disturbed health, especially in Galicia. Alike, lysosomal enlargement was observed in most stations as shown by the extremely low S/V(L) values. V(V(BAS)) and MLR/MET values were markedly high. Overall, employed biomarkers detected exposure to toxic chemicals and disturbed health in mussels from Bay of Biscay, with impact decreasing from April to September. Although hepatocellular nuclear polymorphism and nematode parasitization in fish liver were remarkably prominent in some areas, they cannot be hitherto related to POS, since we lack historical data to determine whether the prevalences found were normal or significantly raised after POS. 相似文献
177.
We present a statistical investigation of the degree of influence that assumptions made in relation to the mechanical parameters of a pylon have on its ground-induced vibrations. The study is set up by using as a key kinematic variable the displacement at the top of a reference, a stand-alone pylon with a uniform cross-section and fixity at its base. Next, statistics are produced using a dimensionless displacement ratio defined between the ‘parental’ and the ‘subsidiary’ cases, the latter define... 相似文献
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