Concentrations of Cd,Zn and Cu in sediments and brown shrimp (Crangon crangon L.) from the Severn Estuary and Bristol Channel,UK

Cd, Zn and Cu levels were determined in sediments and Crangon crangon from 9 sites in the Severn Estuary/Bristol Channel during winter 1999. Metal levels in both shrimp and sediments varied significantly between sites and were related to proximity of input and/or sediment type. In the upper Estuary, Cd levels in shrimp were 100x higher than other reported values whereas sediment Cd contamination was comparable. It is suggested that high Cd levels in shrimp are due to the high inputs and enhanced bioavailability of metal during winter.     

伊尔岗地块的地壳发展

在过去的2500Ma,伊尔岗地块是一个大部分地区仍然保持原状的巨大的太古宙克拉通。伊尔岗地块最显著的平坦地形可能是一个掘出的元古宙不整合,表明现代地壳层姿态是一种太古宙特征。地震折射数据证明在卡尔古利地区地壳厚度为32公里,而在西部和北部边缘具有更厚的地壳(50公里),那里有高速的下地壳层。该地壳层伏于以高级片麻岩层为特征的伊尔岗地块边缘地区的下面。     

Asia-Pacific mussel watch: monitoring contamination of persistent organochlorine compounds in coastal waters of Asian countries

Contamination of persistent organochlorines (OCs) such as PCBs (polychlorinated biphenyls), DDT and its metabolites (DDTs), HCH (hexachlorocyclohexane) isomers (HCHs), chlordane compounds (CHLs), and HCB (hexachlorobenzene) were examined in mussels collected from coastal waters of Asian countries such as Cambodia, China, Hong Kong, India, Indonesia, Japan, Korea, Malaysia, Philippines, Far East Russia, Singapore, and Vietnam in 1994, 1997, 1998, 1999, and 2001 to elucidate the contamination status, distribution and possible pollution sources and to assess the risks on aquatic organisms and human. OCs were detected in all mussels collected from all the sampling sites investigated. Considerable residue levels of p,p(')-DDT and alpha-HCH were found in mussels and the concentrations of DDTs and HCHs found in mussels from Asian developing countries were higher than those in developed nations suggesting present usage of DDTs and HCHs along the coastal waters of Asian developing countries. On the other hand, lower concentrations of PCBs detected in mussels from Asian developing countries than those in developed countries indicate that PCBs contamination in mussels is strongly related to industrial and activities. To our knowledge, this is a first comprehensive report on monitoring OCs pollution in the Asia-Pacific region.     

Enhancement of the benthic communities around an isolated island in the Antarctic Ocean

Insular marine biotas are often richer in faunal diversity than those from the open sea in the same geographical region. The existence of particular island effects were tested under polar conditions by comparing infaunal benthic assemblages on Peter I Island with those of similar latitudes in the open ocean at the Bellingshausen Sea and also from the coast of the Antarctic Peninsula. Sampling was carried out aboard the R/V Hespérides during the expedition named BENTART-2003 from 24 January to 3 March 2003. Benthic samples were collected at 18 stations ranging from 90 to 2 044 m depth, using an USNEL-type box corer (BC) dredge. Representatives of 32 higher taxa of invertebrates were found. Univariate and multivariate analyses revealed various patterns in the data. First, significant differences in polychaete abundance were detected between the stations located in the open sea and the remaining sites (island plus mainland sites). Bivalve abundances were also distinct between island and mainland sampling sites. Sediment columns taken from the island seafloor exhibited the highest rate of bioturbation by the infauna. These findings confirm the model that islands develop distinct assemblages characterized by the enhancement of the benthic communities even in cold waters. Several abiotic factors were measured simultaneously at the seafloor and along the water column to investigate faunal distribution patterns. Significant correlations were found between the benthic assemblages and a combination of two environmental variables: "island effect" (measured as a categorical variable) and the redox state of sediments. Richer and more complex benthic assemblages were found in Peter I Island’s sea bottom, whereas the more depauperate bottoms remained in the open sea.     

Application of the Engineering-Geological Conditions in Land-Use Plans in the Petrvald Region(Czech Republic)

The objective of this paper is to demonstrate necessity to inform relevant parties about engineering-geological conditions for various practical purposes,especially including appropriate land-use planning.However,the relationship between relevant geological information and the geological environment is vital for foundation engineering purposes,especially where demanding structures are involved.This information is most conveniently structured when accumulated information concerning engineering-geological zones is utilized.This necessarily includes knowledge of rock workability and also of the pre-Quaternary bedrock,and these characteristics were then related to the current built-up area and future development according to the land-use plans in a case study are from the Petrvald Region(Czech Republic).The geological environment of area has been severely influenced by anthropogenic effects of deep black coal mining.Results of this research showed that future development should be founded on spoil banks,dumps,and settling basins. According to the land-use plan,this zone occupies 44.9%of the area of interest,and its materials predominantly emanate from mining in the Ostrava-Karvina Coal District.For future foundation structures planned there,it is imperative to consult detailed engineering-geological study.However, attention to and reliance on this necessity is not reflected in the existing land-use plan.     

估算总蒸发的方法

精密的蒸发渗漏仪(Lysimeter)提供了精确测定Et(总蒸发)的唯一直接途径。但由于蒸发渗漏仪的安装和使用需要投资、时间和专门技术,所以其它一些估算Ft的方法是必要的。工程师、农学家和水文工作者及其它工作者都需要精确地估算Et以用于多种目的。为了满足这个需要,这里将对一些比较常用的估算Et的方     

古水文

通过古水文参数对重建古环境尽管有一定局限性,但对恢复古环境仍提供了重要证据。的确,在大陆上的许多地区,第四纪河流沉积物是唯一易于研究古环境的记录。     

天然气水合物相平衡研究的实验技术与方法

介绍了水溶液中天然气水合物相平衡研究的各种实验技术及测定方法 ;对于沉积物中水合物相平衡条件的研究 ,着重探讨了电阻法、超声法及 TDR法等探测技术。实验装置的发展完善和探测技术的提高 ,将极大地推动沉积物中天然气水合物的相平衡条件的研究。     

冰中的碳酸盐成岩作用

由冰川磨碎作用产生的细小碳酸盐颗粒对与融水的相互作用很敏感，因此，这种碳酸盐的同位素组分可以记录这种相互作用。作者研究了瑞士Tsanfleuron冰川沉积物的碳酸盐组合以及底冰内的碎屑，发现底冰碎屑和消融冰碛物存在同位素共线趋势，这被解释为在岩屑和自生方解石之间有混合．多数情况下，