Spatial and temporal changes in microbial diversity of the Marmara Sea sediments

Spatial (10 different locations) and temporal (2 years) changes in characteristics of the Marmara Sea Sediments were monitored to determine interactions between the chemical and microbial diversity. The sediments were rich in terms of hydrocarbon, nitrate, Ni and microbial cell content. Denitrifying, sulfate reducing, fermentative and methanogenic organisms were co-abundant in 15 cm below the sea floor. The local variations in the sediments’ characteristics were more distinctive than the temporal ones. The sulfate and nitrate contents were the main drivers of the changes in the microbial community compositions. N and P were limited for microbial growth in the sediments, and their levels determined the total cell abundance and activity. Seasonal shifts in temperatures of the shallow sediments were also reflected in the active cell abundances. It was concluded that the Marmara Sea is a promising ecosystem for the further investigation of the ecologically important microbial processes.     

Assessment of Water Quality in the Elbe River at Low Water Conditions Based on Factor Analysis

An assessment of water quality measurements during a long‐lasting low water period in the Elbe River is presented. Weekly samples were taken from May to December 2003 at a sampling site in the middle part of the Elbe River. For multivariate data analysis, 34 parameters of 46 samplings were considered. As a result of this analysis, 78% of the variance of the data set is explained by five factors. They can be assigned to the following latent variables: season (37.5%) > tributaries (12.7%) > re‐suspension (10.4%) > discharge (9.4%) > complexation (8.5%). For the investigated sampling site, two key processes were identified as dominating factors on the water quality during low water conditions. First, seasonal phytoplankton development caused changes in redox conditions with consequences for re‐solution of pollutants from sediments. Second, tributaries have a higher impact on the main stream, due to changes in mixing processes. Therefore, in addition to flood investigations, monitoring strategies, and management plans should be developed in order to survey changes in water quality during low water conditions.     

Source Based Characterization and Pollution Profile of a Baker's Yeast Industry

Baker's yeast industry has significant effects on environment due to significant water consumption and high strength wastewater production. Effluents from baker's yeast industry are characterized by high concentrations of biological oxygen demand (BOD₅), chemical oxygen demand (COD), total Kjeldahl nitrogen (TKN), total dissolved solids (TDS), sulfate, and dark brown color. The aim of this study is to provide a detailed quantitative and qualitative identification and characterization of the wastewater sources from different processes of a baker's yeast industry. It is identified that the most polluted wastewater components of the facility are coming from rotary drum filter and evaporation process. However, the highest pollution loads is identified as tank and equipment cleaning effluent due to very high flow rate from this source. The efforts should be on the way to minimize the water usage for the tank and equipment cleaning process, and to recycle less polluted waste streams back to the process.     

气枪激发信号传播的谱元法数值模拟研究

为了研究气枪激发信号的波场,本文利用谱元法对双相介质中波的传播做了数值模拟,分析了波的传播特征.本文主要做了以下工作:(1)研究了使用谱无法(SEM)模拟孔隙弹性介质中波的传播,模拟结果表明,采用谱元法能有效解决双相介质的波场传播模拟问题.(2)验证了Biot理论中慢纵波的存在.双相介质中存在明显的慢纵波,流相波场的慢...     

“井水不犯河水”水文地质学含义初步探讨

利用水化学及同位素水文地质学的方法,对密云水库、潮白河及位于潮白河边的2个地下水分层专门监测井进行取样测试,并结合收集相关资料,从水位、水质及氚、氘、氧-18等同位素方面进行分析研究,对中国古语“井水不犯河水”的水文地质学方面的含义进行了一定的微观层次的分析探讨.得出研究点处潮白河水对50 m外的25 m深的浅井井水有...     

大庆湿地的主要类型及其污染物降解功能价值估算

以大庆市区湿地为研究对象,利用大庆地区2004年LANDSAT TM遥感图形解译数据和实地调查数据,采用地理信息系统技术(GIS),分析了大庆湿地的类型及分布特征;并选用替代法对大庆湿地进行污染物降解功能价值估算。研究表明,降解污染物功能主要是自然湿地所具有的功能,其次是人工湿地中的稻田湿地,经估算自然湿地降解污染物价值为17.90亿元,人工湿地降解污染物价值为0.017亿元,大庆湿地降解污染物价值17.92亿元。     

我国潮流能资源开发评述

潮流能无污染,可预测性高,环境影响小,是一种非常有发展潜力的可再生能源.近年来,潮流能开发技术发展迅速,日趋成熟.我国潮流能资源丰富,合理有效的开发潮流能资源对保障我国的能源安全意义重大.文中总结我国潮流能开发利用中存在的主要问题,提出我国潮流能开发工作的几点建议.     

Spatial variation in river runoff into a coastal area — An ecological approach

Carbon and nitrogen stable isotopes were used to investigate spatial variation in terrestrial particulate organic matter (POM) input to a coastal area off the Tagus river estuary. Isotopic variation in higher trophic level organisms was also examined, along the coast. This study was carried out in late summer, after a period of 3 months of low river flow. The overall aim was to determine if under such conditions the coastal area is enriched by the river plume and, particularly, if lower secondary productivity should be expected in some areas. Spatial variation was detected as a gradient of decreasing terrestrial input with increasing distance from the river. It was concluded that terrestrial carbon input was also incorporated into higher trophic levels and that organisms with lower mobility are more sensitive to the gradient in terrestrial input. Even in low flow conditions the whole fishing area remained under the influence of the river plume, which still accounted for 24% of the total POM 30 km from the river mouth. Additionally, δ¹⁵N values indicated pollution input from the river Tagus.     

基于OSCAR需求指标对遵义市地面气象观测站网现状分析研究

基于观测系统能力分析和审查工具（OSCAR）选取各气象应用领域对地面观测要素的需求指标,对遵义市地面自动气象观测站网现状进行评估分析,提出相应规划思路,旨在提高地面自动气象站网优化布局,推进气地面象观测业务的高质量发展。     

2000年汛期河南持续暴雨的天气形势和水汽分析

通过对2000年6月23日－7月15日河南省出现的3次连续3天以上的暴雨，大暴雨过程的降水特征－背景形势，影响系统和水汽条件等方面的分析，揭示了有利于连续性暴雨产生的水汽条件和两种环流背景场。