Total mercury body burden in Pacific harbor seal, Phoca vitulina richardii, pups from central California

To determine body and tissue compartment-specific burdens (mg) of total mercury (THg), tissues were weighed and analyzed for THg concentration (microg/g fw) in Pacific harbor seal (Phoca vitulina richardii) pups from central California in 2006. THg concentrations were related as follows: hair > liver = kidney = pelt > muscle > other = heart > brain > blubber > bone. THg burden, however, was related as: pelt = muscle > liver = other > kidney = blubber > brain = heart > bone. THg concentration and burden in muscle were strongly associated with delta(15)N. delta(13)C and delta(15)N values were significantly greater in muscle than liver, and delta(13)C was significantly lesser the longer animals were in rehabilitation. Because THg concentration and burden in muscle correlated most significantly with other tissue compartments, we recommend that muscle from the specific sites we sampled be used instead of liver or hair for biomonitoring THg in harbor seals. Assessment of proportional THg burdens within each tissue compartment for harbor seals pups included use of a conceptual model, allowing for more complete visual characterization of THg body burden.     

东濮凹陷断层封堵模式探讨

以构造地质学和石油地质学基础理论为指导,通过对东濮凹陷中大量的复杂断块油气田的油藏解剖分析,建立了岩性配置封堵、时间配置封堵、主应力封堵、泥岩塑性流动和涂抹封堵、排替压差封堵等五种主要的断层对油气的封堵模式。对提高断层油气勘探开发成功率有一定作用。     

水合物层下伏游离气渗漏过程的数值模拟及实例分析

海洋环境中天然气水合物层是理想的毛细管封闭层,游离气被抑制在水合物层下,游离气层的气体压力随气体聚集和气层厚度的增加而升高,当气压超过封闭层的毛细管力时,游离气会克服毛细管进入压力、刺入上伏封闭层孔隙空间,毛细管封闭作用随之消失,从而形成水合物下伏游离气向海底的渗漏.通过对该过程进行的数值模拟计算表明：渗漏气体是以活塞式驱动上伏沉积层中的孔隙水向海底排出,水合物稳定带内流体渗漏速度随水流柱高度的减小而增加,当水流阻抗大于相应沉积层段的静岩压力时,沉积层将转变为流沙,流沙沉积被海流移除后便在海底留下凹陷麻坑.麻坑形成后流体运移通道演化为气体通道,气体快速排放.麻坑深度主要取决于游离气层的厚度和水合物封闭层（底界）的深度,而与沉积层的渗透率无关.麻坑深度一定程度上指示了渗漏前水合物层下伏游离气层的资源量.对布莱克海台海底麻坑深度的数值模拟计算表明,形成4 m深的海底麻坑需要至少22 m厚的游离气层.     

First health and pollution study on harbor seals (Phoca vitulina) living in the German Elbe estuary

The Elbe is one of the major rivers releasing pollutants into the coastal areas of the German North Sea. Its estuary represents the habitat of a small population of harbor seals (Phoca vitulina). Only little is known about the health status and contamination levels of these seals. Therefore, a first-ever seal catch was organized next to the islands of Neuwerk and Scharhörn in the region of the Hamburg Wadden Sea National Park. The investigations included a broad set of health parameters and the analysis of metals and organic pollutants in blood samples. Compared to animals of other Wadden Sea areas, the seals showed higher γ-globulin levels, suggesting higher concentrations of pathogens in this near-urban area, elevated concentrations for several metals in particular for V, Sn, Pb, and Sr, and comparable ranges for chlorinated organic contaminants, except for elevated levels of hexachlorobenzene, which indicates characteristic inputs from the Elbe.     

Crusting effects on erosion processes under simulated rainfall on a tropical Alfisol

Sealing and crusting of soil surfaces have dramatic effects on water infiltration into and runoff from soils, thereby greatly influencing erosion processes. This study focused on the effect of the initial stage of crusting on inter-rill erosion processes for a crust-prone Alfisol sampled from south-central India. Soil aggregates ranging from 2·4 to 8 mm collected from ploughed (PL) and naturally vegetated (NV) treatments were subjected to rainfall simulation under laboratory conditions. Runoff from PL soil aggregates was 2–2·5 times higher, while percolation was 20–100% lower, than for NV aggregates. Soil wash and splash losses were 0·5–3 times greater for PL than for NV soil. Runoff and inter-rill erosion were significantly higher during the wet simulation run compared with the dry run. The results indicated that NV soil aggregates were more resistant to breakdown from raindrop impact and slaking, and subject to less rapid sealing, than PL soil. Total soil loss was influenced most by initial aggregate stability and the extent of seal development. Splash and wash losses of soil both increased as a result of surface sealing regardless of soil condition for short (30–60 min) rainfall durations. High drying rates resulted in the highest crust bulk densities. Increased crust strength for PL soil compared with NV soil reflected the greater susceptibility of cultivated soil to surface sealing and crusting. © 1998 John Wiley & Sons, Ltd.     

塔里木盆地乌什凹陷白垩系冲积扇—扇三角洲沉积相及有利储盖组合

通过对乌什凹陷南缘坳陷乌参1井及北缘露头剖面地详细观察,结合测井曲线形态和地震剖面综合分析,乌什凹陷北部和南部由于受构造条件、古气候和物源的影响,发育了截然不同的沉积相类型,北缘露头区以滨浅湖相沉积为主,南部坳陷区则发育了典型的冲积扇—扇三角洲粗粒沉积相。这套沉积碎屑岩颗粒粒度悬殊且不连续,砾岩和砂岩间常显示粒度不连续的现象,剖面中巨厚层砾岩常与中厚层细砂岩、粉砂岩、泥岩沉积层直接接触,无过渡性粒级存在。造成这种现象的主要原因是由于北缘露头区处于相对稳定的构造条件及较远的物源条件,而南缘坳陷区由于靠近温宿凸起物源并受断裂控制。乌什凹陷发育两套较好的储盖组合,分别是亚格列木组—舒善河组中下部砂砾岩与舒善河组泥岩、含膏泥岩和巴什基奇克组—库姆格列木群底砂砾岩与库姆格列木群盐层、含膏泥岩。乌参1井已在第一套储盖组合中的舒善河组中下部的扇三角洲砂体中获得重大发现,这些砂体为扇三角洲前缘的砂坝、辫状河水道充填可形成较好的储层。第二套储盖组合中巴西盖组和巴什基奇克组的砂体分布广泛,岩性较致密;储层厚度较大,纵向发育集中,但物性较差,总体上属于一套中等储盖组合,预测离物源区一定距离应分布有优质储集相带。      

南极无冰区生态与环境变化在粪土层中的记录

极地海鸟、海兽等生物排泄物的堆积层和含粪的沉积层是进行极地生态地质学研究的良好载体。从生物粪土沉积层中恢复出的企鹅、海豹数量变化记录表明,历史时期南极企鹅、海豹种群数量出现过显著的波动。在新冰期时企鹅数量锐减,气候过冷或过暖都不利于它们的生存,南极海豹数量变化也受到气候变化、海冰条件和取食行为的控制。另外,南极海豹毛和生物粪土层中还保存了过去几千年人类文明的历史信息,汞（Hg）含量的波动与人类冶金文明的盛衰存在明显的响应关系。     

Transfer of lipids from plankton to blubber of harp and hooded seals off East Greenland

Sub-Arctic marine ecosystems are some of the most productive ecosystems in the world's oceans. The capacity of herbivorous zooplankton, such as Calanus, to biosynthesize and store large amounts of lipids during the short and intense spring bloom is a fundamental adaptation which facilitates the large production in these ecosystems. These energy-rich lipids are rapidly transferred through the food chain to Arctic seals. The fatty acids and stable isotopes from harp seal (Phoca groenlandica) and hooded seal (Cystophora cristata) off East Greenland as well as their potential prey, were analysed. The results were used to describe the lipid dynamics and energy transfer in parts of the East Greenland ecosystem. Even if the two seal species showed considerable overlap in diet and occurred at relatively similar trophic levels, the fatty acid profiles indicated that the bases of the food chains of harp and hooded seals were different. The fatty acids of harp seals originate from diatom-based food chain, whereas the fatty acids of hooded seals originate from dinoflagellate and the prymnesiophyte Phaeocystis pouchetii-based food chain. Stable isotope analyses showed that both species are true carnivores on the top of their food chains, with hooded seal being slightly higher on the food chain than harp seal.     

Addressing multiple goals of ecosystem approach through deliberation and technology development

This paper studies two participatory processes to manage the interactions between seals and coastal fishing in Finland. One was a deliberative multi-stakeholder process, in which the stakeholders in a region approached the problem solving by joint problem definition. The other process was a technology development project to reduce the damage by seals and seal by-catch. This paper discusses the contribution of the processes to maintain economic viability of the coastal fishery without jeopardising the conservation of seals. It concludes that both processes address important aspects of maintaining a dynamic stability in a socio-ecological system of coastal fishing, but a combination of the approaches would better allow dealing with the problem's political aspects and fishing practices that are intertwined in various ways.     

双通道水龙头设计使用中的几个问题

简要介绍了双通道水龙头设计和使用中遇到的问题及相应的解决办法。