PREDICTING FECAL COLIFORM BACTERIA LEVELS IN THE CHARLES RIVER,MASSACHUSETTS, USA1

In Massachusetts, the Charles River Watershed Association conducts a regular water quality monitoring and public notification program in the Charles River Basin during the recreational season to inform users of the river's health. This program has relied on laboratory analyses of river samples for fecal coliform bacteria levels, however, results are not available until at least 24 hours after sampling. To avoid the need for laboratory analyses, ordinary least squares (OLS) and logistic regression models were developed to predict fecal coliform bacteria concentrations and the probabilities of exceeding the Massachusetts secondary contact recreation standard for bacteria based on meteorological conditions and streamflow. The OLS models resulted in adjusted R²s ranging from 50 to 60 percent. An uncertainty analysis reveals that of the total variability of fecal coliform bacteria concentrations, 45 percent is explained by the OLS regression model, 15 percent is explained by both measurement and space sampling error, and 40 percent is explained by time sampling error. Higher accuracy in future bacteria forecasting models would likely result from reductions in laboratory measurement errors and improved sampling designs.     

Trait‐based prediction of extinction risk of small‐bodied freshwater fishes

Small body size is generally correlated with r‐selected life‐history traits, including early maturation, short‐generation times, and rapid growth rates, that result in high population turnover and a reduced risk of extinction. Unlike other classes of vertebrates, however, small freshwater fishes appear to have an equal or greater risk of extinction than large fishes. We explored whether particular traits explain the International Union for Conservation of Nature (IUCN) Red List conservation status of small‐bodied freshwater fishes from 4 temperate river basins: Murray‐Darling, Australia; Danube, Europe; Mississippi‐Missouri, North America; and the Rio Grande, North America. Twenty‐three ecological and life‐history traits were collated for all 171 freshwater fishes of ≤120 mm total length. We used generalized linear mixed‐effects models to assess which combination of the 23 traits best explained whether a species was threatened or not threatened. We used the best models to predict the probability of 29 unclassified species being listed as threatened. With and without controlling for phylogeny at the family level, small body size—among small‐bodied species—was the most influential trait correlated with threatened species listings. The k‐folds cross‐validation demonstrated that body size and a random effect structure that included family predicted the threat status with an accuracy of 78% (SE 0.5). We identified 10 species likely to be threatened that are not listed as such on the IUCN Red List. Small body size is not a trait that provides universal resistance to extinction, particularly for vertebrates inhabiting environments affected by extreme habitat loss and fragmentation. We hypothesize that this is because small‐bodied species have smaller home ranges, lower dispersal capabilities, and heightened ecological specialization relative to larger vertebrates. Trait data and further model development are needed to predict the IUCN conservation status of the over 11,000 unclassified freshwater fishes, especially those under threat from proposed dam construction in the world's most biodiverse river basins.     

Cladocerans under conditions of small river damming by man and beavers

In beaver ponds, the species diversity, abundance, biomass, and production of cladocerans and the amount of food consumed by them have increased and the composition of dominant species has changed as compared to those in the stretches of small rivers with running water or dammed by man. The stimulating effect of water from a beaver pond has been confirmed in laboratory experiments. The average number of juvenile Ceriodaphnia affinis produced by one female was considerably greater in this water than in the water from flowing and dammed (by man) river stretches.     

地铁站附属地下餐饮空间噪声特征分析

利用专业噪声测量设备及噪声频谱分析设备,对地铁站附属地下餐饮空间区域噪声进行监测,绘制噪声小时频谱。经分析发现地铁附属地下餐饮空间声环境会受到客流、空间位置及餐铺建筑结构影响,因此在该类空间进行降噪设计中应充分考虑这些因素的影响。     

Assessment of Environmental Water Demands (EWD) of Forests for Two Distinct Indian Ecosystems

Sustainable use of water and land resources requires that these scarce resources be appropriately allocated among various competing human activities. Worldwide, there is a realization now that sustainable river basin management should be accorded the highest priority, because it deals not only with technical, but also with ecological and socioeconomic aspects, and thus calls for a multidisciplinary and integrated approach. However, most of the policy and planning documents have either remained silent, or have made only implicit reference to the importance of environmental water demand (EWD) and its quantification. Therefore, in the light of its importance, a methodology has been evolved in this article for quantifying EWD for various forested areas in two distinctly different Indian river basins: Brahmani (humid zone) and Sabarmati (dry zone). The article analyzes and discusses EWD estimates at three different spatial levels: river basins, states, and districts within them, and finally presents a comparative analysis of all these results. Findings of the present study will be immensely useful in understanding various ecological issues connected with water resource projects and proposals in these river basins.     

上海城市河道治理工程简介

对上海中心城区内5条污染河道的背景情况、治理工程措施及实践效果进行了介绍,对国内相似地区开展城市水环境整治工作具有一定的参考价值。     

某地下大型商业建筑防火分隔方案设计和评估

针对某地下大型商业建筑消防设计在防火分隔方面存在的问题,分析几种常用防火分隔方法的适用性,初步设计几种防火分隔替代方案.采用建筑防火性能化设计思想,分析替代方案所应达到的安全目标,利用火灾动力学模拟软件FDS评估这些方案的分隔效果,给出火灾时防火卷帘迎火面和背火面的温度发展曲线.数值模拟结果表明防火分隔方案3能够达到防火墙的分隔效果,满足该建筑的消防安全要求.     

Bison and cattle grazing management,bare ground coverage,and links to suspended sediment concentrations in grassland streams

This study quantified the impact of bison and cattle grazing management practices on bare ground coverage at the watershed, riparian, and forested riparian scales within the Flint Hills ecoregion in Kansas. We tested for correlations between bare ground coverage and fluvial suspended sediment concentrations during base‐flow and storm‐flow events. We used remotely sensed imagery combined with field surveys to classify ground cover and quantify the presence of bare ground. Base‐flow water samples were collected bi‐monthly during rain‐free periods and 24 h following precipitation events. Storm‐flow water samples were collected on the rising limb of the hydrograph, using single‐stage automatic samplers. Ungrazed treatments contained the lowest coverage of bare ground at the watershed, riparian, and forested riparian scales. Bison treatments contained the highest coverage of bare ground at the watershed scale, while high‐density cattle treatments contained the highest coverage of bare ground at the riparian and forested riparian scales. In bison and cattle‐grazed treatments, a majority of bare ground was located near fence lines, watershed boundaries, and third‐ and fourth‐order stream segments. Inorganic sediment concentrations at base flow were best predicted by riparian bare ground coverage, while storm‐flow sediment concentrations were best predicted by watershed scale bare ground coverage.     

论我国国际河流可持续开发利用的问题与法律对策

中国是世界上国际河流最多的国家之一,在国际河流的开发利用方面采取了一定的措施并取得了一定的成绩,但是在国际河流的可持续开发利用中仍存在不少问题,需要完善相关的国际与国内法律制度并采取其他有效的措施予以解决。从中国国际河流的概况出发,阐述对其进行可持续的开发利用在促进中国经济发展、加强民族团结以及保障国防安全等方面的重大意义,进而分析中国国际河流在可持续开发利用中存在的问题,包括立法缺失、保障措施缺位、管理机构缺乏等,最后从完善可持续开发利用的前提要素、确立可持续开发利用的基本原则、完善可持续开发利用的立法以及积极参与可持续开发利用的国际合作等方面提出解决上述问题的对策思考,以促进和保障我国国际河流可持续开发利用的实现.     

The occurrence of antihistamines in sewage waters and in recipient rivers

Background, aim and scope  Each year, large quantities of pharmaceuticals are consumed worldwide for the treatment and prevention of human and animal diseases. Although the drugs and the metabolites observed in the wastewaters and in the environment are present at concentrations several orders of magnitude lower than the concentrations required to exert their effects in humans or animals, their long-term impact on the environment is commonly not known. In this study, the occurrence of six antihistamines, which are used for the relief of allergic reactions such as hay fever, was determined in sewage treatment plants wastewaters and in recipient river waters. Materials and methods  The occurrence of the antihistamines cetirizine, acrivastine, fexofenadine, loratadine, desloratadine and ebastine in sewage treatment plants wastewaters and in recipient river waters was studied. The analytical procedure consisted of solid-phase extraction of the water samples followed by liquid chromatography separation and detection by a triple-quadrupole mass spectrometer in the multiple reaction mode. Results  Cetirizine, acrivastine and fexofenadine were detected in both influent and effluent wastewater samples at concentration levels ranging from about 80 to 220 ng/L, while loratadine, desloratadine and ebastine could not be detected in any samples. During sewage treatment, the concentration of the antihistamines dropped by an average of 16–36%. Furthermore, elevated concentrations of antihistamines were observed in samples collected during the season of most intensive plant pollen production, i.e. in May. In the river water samples, the relative pattern of occurrence of cetirizine, acrivastine and fexofenadine was similar to that in the wastewater samples; although the concentration of the compounds was substantially lower (4–11 ng/L). The highest concentrations of the studied drugs were observed near the discharging point of the sewage treatment plant. Discussion  The highest concentrations of antihistamines in STP wastewaters correlate with the outbreak of allergic reaction caused by high amounts of plant pollens in the air. The analysis results of the river water samples show that the antihistamines are carried far away from the effluent discharge points. They may account for a part of the mix of pharmaceuticals and of pharmaceutical metabolites that occur downstream of STPs. Conclusions  Antihistamines are poorly degraded/eliminated under the biological treatment processes applied in the wastewater treatment plants and, consequently, they are continuously being discharged along with other drugs to the aquatic environment. Recommendations and perspectives  As a huge quantity and variety of drugs and their metabolites are continuously discharged to rivers and the sea, the compounds should be considered as contaminants that may possess risks to the aquatic ecosystem. Further studies are urgently needed on the environmental fate of the antihistamines and other pharmaceuticals in the aquatic environment. These studies should be concerned with the stability of the compounds, their transformation reactions and the identity of the transformation products, the distribution of drugs and their uptake and effects in organisms. On the basis of these studies, the possible environmental hazards of pharmaceuticals may be assessed.