A Comparison of the Bacterial Microflora between Coastal Sites in Qingdao, P.R. China and Loch Fyne, Scotland

Aerobic, heterotrophic bacteria, recovered from two sites located on the west coast of Scotland, were compared to cultures obtained in a similar way from industrial, aquacultural and clean sites in the vicinity of Qingdao, Shandong, P.R. China. Gram-negative bacterial cultures were examined by BIOLOG-GN, and the data analysed by the simple matching (SSM) and Jaccard coefficients (SJ) and unweighted average linkage clustering using NTSys. The output revealed that 20% of the bacteria, namely, Acinetobacter johnsonii, Aquaspirillum dispar, Pseudomonas spp. (two groups), Sphingobacterium sp., Vibrio sp., V. campbellii, V. mimicus and V. hollisae, were common between the two geographical locations. However, the study revealed shortcomings with the BIOLOG-GN system for the study of coastal Gram-negative bacteria.     

应用高斯法解释倾斜厚板磁异常

引言对于厚板磁剖面计算机反演解释方法已有许多报道.McGrath和Hood叙述了一种实质上是试凑的方法,依次任意改变厚板的每个参数,直到找到一组拟合最佳的参数为止.Rao等人(1973)介绍了一种微分校正法,来改善对厚板所给的初始参数.Moo,     

数学模型、样本和品位估计量

矿体的数学模型一个矿体的数学模型,并不代表矿体本身,而只能反映矿体的某些特征,因此,为了表征不同的矿体,就需要采用不同的数字模型.取自一种模型的样本的特征,应与取自同类实际矿体的样本的特征一致.精确的数学模型是一种有效的工具,它可以用来推测取自实际矿体的样本的各种性质.这样的数学模型,可以用来反映具有特     

自然环境的系统分析和综合研究

早产,这是上个世纪中叶E.黑克尔提出生态学概念的情况。他把生态学定义为研究生物及其与环境关系的科学。     

加拿大地盾格伦维尔成矿省部分地区矿产资源的概率评价

本文介绍用广义贝叶斯分类法结合回归分析来评价加拿大格伦维尔省部分地区的矿产资源.利用该区内一片经过详细勘探的地区作为控制区进行了地质和经济资料的分析,获得了与矿体密切有关的某些地质因素.根据这些因素拟定了回归模型与贝叶斯分类模型进一步预测新区的矿产价值与成功概率,最后圈定出值得勘探的目标.     

新观点下的夷平面——梯级山地——单斜地

地球表面的大地貌是内外力辩证的共同作用的结果和过程,由这一认识出发,有关世界上山地和高地形成的三组问题,在纽续地貌学的研究和讨论上,是具有特别兴趣和重大的意义。     

应用概率图解确定地球化学数据异常下限的方法

前言概率格纸可用来简明直观地表示各种类型的地球化学数据,是推断地球化学分析结果的一种辅助手段.已发表过不少文章,但对异常下限的确定都未作详细论述.在化探工作中,异常下限是指能够将不同原因、基本性质不同的高低数值区分开的一个特定的值,将较高的异常从较低的背景值辨认出     

A first estimate of ground water ages for the deep aquifer of the Kathmandu Basin, Nepal, using the radioisotope chlorine-36

The Kathmandu Basin in Nepal contains up to 550 m of Pliocene-Quaternary fluvio-lacustrine sediments which have formed a dual aquifer system. The unconfined sand and gravel aquifer is separated by a clay aquitard, up to 200 m thick, from the deeper, confined aquifer, comprised of Pliocene sand and gravel beds, intercalated with clay, peat, and lignite. The confined aquifer currently provides an important water supply to the central urban area but there are increasing concerns about its sustainability due to overexploitation. A limited number of determinations of the radioisotope 36Cl have been made on bore waters in the basin, allowing us to postulate on the age of ground water in the deeper, confined aquifer. Ground water evolution scenarios based on radioisotope decay, gradual dissolution of formational salts as the ground waters move downgradient, and flow velocity estimations produce comparable ground water ages for the deep waters, ranging from 200,000 to 400,000 years. From these ages, we deduce a mean ground water flow velocity of only 45 mm/year from recharge in the northeast to the main extraction region 15 km to the southwest. We thus estimate current recharge at about 5 to 15 mm/year, contributing 40,000 to 1.2 million m3/year to the ground water system. Current ground water extraction is estimated to be 20 times this amount. The low specific discharge confirms that the resource is being mined, and, based on current projections, reserves will be used up within 100 years.     

Offshore oil platforms and fouling communities in the southern Arabian Gulf (Abu Dhabi)

This study examined the fouling organisms on the legs of offshore oil platforms at two sites in the southern Arabian Gulf (offshore Abu Dhabi, United Arab Emirates). 100% of the metal structures was colonized by encrusting organisms. Both the number of individuals and the total biomass tended to decrease with depth. The total weight of dead shells always exceeded that of living organisms. Sessile filter feeders dominated the biomass, whereas small mobile forms had the largest number of individuals. The biomass at the deeper platform (22 m) was dominated by bivalves, barnacles and bryozoans, while polychaetes and amphipods had the greatest number of individuals. Biomass values here ranged from 1 g/0.1 m2 at 20 m to 147 g/0.1 m2 at 5 m; the corresponding individual numbers were 266 (20 m) and 11,814 indiv./0.1 m2 (5 m). The results at the shallower platform (11 m) differed in several respects: barnacles clearly dominated over bivalves, and sponges exceeded byrozoans, while total individual numbers fell due to a decline in polychaete dominance. Biomass values here ranged from 84 g/0.1 m2 at 10 m to 153 g/0.1 m2 at 0 m; the corresponding individual numbers were 695 (10 m) and 3,125 indiv./0.1 m2 (0 m). The potential role of such fouling communities on artificial structures in the Gulf is discussed.     

Composition, distribution and sources of polycyclic aromatic hydrocarbons in sediments of the Gulf of Trieste, Northern Adriatic Sea

The composition, distribution and the sources of polycyclic aromatic hydrocarbons (PAHs) in the surficial sediments of the Gulf of Trieste were investigated. To document the spatial PAH input, surficial sediment samples from 17 locations throughout the Gulf were analysed. The total PAH load determined in the surficial sediment samples are between 30 and 600 ng g-1, and were the highest in the immediate vicinity of the Port of Trieste. The PAH contents decline rapidly with increasing distance from the shore. The ratios of methylphenanthrenes/phenanthrene and methylpyrene/pyrene are sensitive indicators of the origin of PAH pollution in the Gulf which is mostly pyrolitic. The phenanthrene/anthracene ratio was used to determine the approximate location and distance from the source of PAH pollution, while 1-methy 1-7-isopropylphenanthrene (retene) was used as indicator for forest fires. A sediment depth profile indicates a major increase in the PAH concentrations after the First World War.