动态贴近度法在徒骇河干流水质监测点优化中的应用

根据2010—2012年的COD、BOD5、NH3-N、TP和Cr6+的例行监测数据,采用动态贴近度法,对徒骇河干流13个监测点进行优化。分别计算丰水期、平水期和枯水期的最优点和最劣点的距离,从而计算出最优贴近度值。利用t检验和F检验对优化结果进行准确度和精确度检验,结果表明,优化后的8个监测点的监测数据可以代表整个干流的水质状况。     

近岸海域国控环境质量监测点位优化研究

近岸海域环境监测是掌握其环境质量状况,摸清污染来源和影响范围的必要手段。监测点位是环境监测的基础,监测点位优化是提高环境监测代表性的必要手段。按照《近岸海域环境监测点位布设技术规范》(HJ 730—2014)的要求,梳理了点位优化工作的基本流程,经过试优化,预计在全国将增设122个国控监测点位。其中,76个在原有监测点位中选择增设,46个按照规范要求新设。利用2013年监测结果进行插值分析,调整前后水质总体变化小,未出现颠覆性结论,同时提高了对陆源影响区域水质的监控能力。     

基于GIS的城市重大危险源选址研究

近年来,城市重大危险源的安全问题日益突出,对城市的健康安全发展构成了极大威胁,因此,如何进行城市重大危险源选址成为现代社会研究的重要内容。利用GIS空间分析技术,对影响重大危险源选址布局的空间信息进行处理,将道路图、土地利用规划图、城市遥感影像、城市基础设施等与城市区划图相结合,以获取适宜选址的可行域。利用模糊综合评价理论,选出影响选址的因素集和评语集,通过模糊运算评判可行域,并由实例验证了该选址方法,最终得出城市重大危险源最优选址方案。因此,进行城市重大危险源的选址研究具有现实可行的意义,有助于提高城市的整体安全水平。     

日本地震实时监测系统中液化识别方法可行性研究

日本地震超高密度实时监测系统(SUPREME)建设中的核心技术之一是依据强震记录对液化场地进行反演识别,系统中目前使用的是Suzuki法,但实际应用效果并不理想。选取不同地震下多种类别场地上的实际地震记录,对Suzuki法的适用性进行了研究,讨论了其不同指标对不同类别场地识别结果的影响。分析表明:Suzuki法对不同类别非液化场地的识别能力不同,最显著的缺陷是易将软土场地与液化场地混淆;方法所使用的4个识别指标中,过零周期为控制参数,其它指标仅起到初判作用;方法出现误判的原因是液化场地的过零周期范围与非液化中软土场地上的过零周期范围存在明显交叉,而这一点理论上是无法避免的客观存在;改进的方法是应放弃现有进行绝对值对比的做法,改用地震动某些参数的相对变化作为新的识别指标。     

地震现场资料收集的标准化与快速传送

破坏性地震现场的震害资料调查和收集对地震灾害的损失评估、地震应急救援、恢复重建以及科学研究等具有重要意义。总结了当前我国地震现场震害资料的收集和传送方式,指出了普遍存在的主要问题。结合当前电子化、信息化的发展现状和地震现场工作资料整理的相关规定,提出了现场灾害资料标准化收集和快速传递的初步设想和方案。实现这些设想和方案对提高地震现场震害资料的质量和标准化具有重要意义,并将极大地提高现场灾害信息的传送速度。     

安康中心城市饮用水水源地环境现状调查分析及保护措施

根据安康中心城市两个饮用水水源地环境现状调查和水质监测结果,按照国家《地表水环境质量标准》(GB3838-2002),采用比照法进行了环境质量现状评价。同时,针对目前水源地存在的环境问题,提出了法律法规和制度保护措施、组织保障措施、各级水源保护区的工程治理措施,以及相应的生态修复与建设重点工程和管理能力建设重点工程等,对于改善水源地生态环境系统,有效地保证安康市生活饮用水质量和促进区域水资源可持续利用具有一定的指导作用。     

Forest Cover and Stream Flow in a Headwater of the Blue Nile: Complementing Observational Data Analysis with Community Perception

This study analyses the relation of forest cover and stream flow on the 266 km² Koga watershed in a headwater of Blue Nile Basin using both observed hydrological data and community perception. The watershed declined from 16% forest cover in 1957 to 1% by 1986. The hydrological record did not reveal changes in the flow regime between 1960 and 2002 despite the reduction in forest area. This agrees with the perception of the downstream community living near the gauging station. The upstream community, however, reported both decreases in low flows and increases in high flows shortly after the forest cover was reduced. The upstream deforestation effect appeared to have been buffered by a wetland lower in the watershed. This study concludes that community perception can be a complement to observational data for better understanding how forest cover influences the flow regime.     

Establishment of control site baseline data for erosion studies using radionuclides: a case study in East Slovenia

The aim of the present study was to establish a reference site and its soil characteristics for use of fallout radionuclides in erosion studies in Slovenia. Prior to this study, no reference site and baseline data existed for Slovenia for this purpose. In the agricultural area of Gori?ko in East Slovenia, an undisturbed forest situated in Šalamenci (46°44’N, 16°7’E), was selected to establish the inventory value of fallout ¹³⁷Cs and to establish a baseline level of multi-elemental fingerprint (major, minor, trace elements including heavy metals) and naturally occurring radionuclides in soils. A total of 20 soil profiles were collected at four 10 cm depth increments for evaluation of baseline level of ¹³⁷Cs inventory. An exponential distribution for ¹³⁷Cs was found and the baseline level inventory was established at 7300 ± 2500 Bq m⁻² with a coefficient of variation of 34%. Of this mean present-day inventory, approximately 45% is due to the Chernobyl contribution.The physical degradation of soils through erosion is linked with biochemical degradation. This study introduces an approach to establishment of the naturally occurring radionuclide and elemental fingerprints baseline levels at a reference site which can provide comparative data to those from neighbouring agricultural fields for assessment of soil redistribution magnitude using fallout radionuclides. In addition, this information will be used to determine the impact of soil erosion processes and agricultural practices on soil quality and redistribution within agricultural landscapes in Slovenia.     

Occurrence and congeners specific of polychlorinated biphenyls in agricultural soils from Southern Jiangsu, China

A total of 198 agricultural soil samples were collected from Zhangjiagang and Changshu in Southern Jiangsu for analysis of 13 polychlorinated biphenyls （PCBs） in order to assess the levels of pollution, sources, area distribution, and potential risk for the environment. All methods were rigorously tested and an adequate quality control was ensured. Only one site had no PCBs residues, and the highest total PCBs concentration in the surface soils was 32.83 ng/g. The average concentration in all the soil samples was 4.13 ng/g, signaling low-level pollution. Tetra-, penta-, and hexa-chlorinated biphenyls were dominant species in soil samples, accounting for more than 75% of ∑PCBs in the soil samples. PCB118 was the most abundant congener in all the samples. The PCB118 was about 20% of ∑PCBs. The soil organic matter content showed only a weak correlation with the levels of all PCB congeners, in which a better correlation was noted for the more volatile lighter PCB congeners than for the heavier homologues. To a certain extent, the sources and land use seemed to influence the levels of PCBs.     

贮灰场灰水污染物运移的数值分析

从环境保护的角度出发,针对灰水溶质运移污染地下水的问题,应用混合防渗材料作为防渗层,通过有限元程序模拟贮灰场的实际运行条件,进行了有无防渗层条件下污染物运移的对比计算分析.结果表明,防渗层可有效地减少灰水渗漏量,缩小污染物的长期扩散范围;在灰场底部和内侧设置防渗层是有效的防污染措施.