页岩-钢渣组合填料湿地强化脱氮除磷研究

以城市污水A/O工艺出水为处理对象,运用页岩和钢渣物化除磷、调控进水碳氮比和氮素氧化性等技术手段,在中试规模上研究了页岩和钢渣组合填料湿地的脱氮除磷效能及影响因素.结果表明,当COD面积负荷率、TN面积负荷率、TP面积负荷率、HRT(水力停留时间)分别为6.5～20.7 g·(m²·d)^-1、2.57～8.22 g·(m²·d)^-1、0.41～1.32 g·(m²·d)^-1、0.5～1.6d时,①氨氮、亚硝态氮和硝态氮的去除率分别为85.8%、56.3%和18.6%,TN去除率为58.0%,TN面积负荷去除率为3.58g·(m²·d)^-1,TN反应动力学常数为0.31 m·d^-1,TN面积负荷去除率随进水TN负荷的增加而线性增加.②TP去除率为90.4%,TP面积负荷去除率为0.89 g·(m²·d)^-1,TP反应动力学常数为0.86 m.d^-1,TP面积负荷去除率随进水TP负荷的增加而线性增加.③水温、HRT、氮素组分、C/N等因素对湿地系统的脱氮除磷效率有显著影响.TN面积负荷去除率随HRT、COD/TN值的增加而幂函数增加.TN面积负荷去除率随水温(、NO₂^--N+NO₃^--N)/TN值的增加而呈指数函数增加.     

黑液蒸发器液室结垢的原因及改进措施

造纸黑液治理技术中，蒸发器结垢是黑液蒸发中普遍存在而难以解决的问题之一。在此通过对板式降膜蒸发器液室结垢原因的分析与探讨，多角度，多侧面提出预防及改进措施，达到提高蒸发效率的目的。     

Influence of Black Shales on Soils and Edible Plants in the Ankang Area, Shaanxi Province, P. R. of China

The Ankang black shales in P. R. of China provides an important example of natural geological materials containing toxic elements. This paper presents the results of environmental geochemical research on black shales, soils, waters and edible plants in the Ankang area, Shaanxi Province, P. R. of China. The study area lies in the northern margin of the Yangtze Platform; there are black shales which contains black shale, carbonaceous rocks and coal in the Cambrian Donghe Formation throughout the area. Mean trace element concentrations of the coal were high. Soils derived from these rocks tend to reflect their extreme geochemical composition. Chemical analysis of common plant species in the Ankang area showed a heterogeneous distribution of Se, Mo, and V within a single and among plant species. Selenium was more concentrated in radish than in legumes, and in potato more than in green vegetable. High V concentrations were found in two kinds of Chinese tea. Legume had more Mo in the seed than potato, although Mo concentrations in radish vary. Higher concentrations of Se and Mo are present in the leaf of radish.     

黑碳监测在博物馆文物环境评价中的应用研究

每个博物馆所处地理环境、气候均有所不同,如何对博物馆展厅环境进行全面监测,最终对陈列展示的文物形成一套完整而有效的保护体系,是文物保护工作人员研究的主要课题。试验采用黑碳监测仪对上海中国航海博物馆展厅内部及馆外空气质量同步进行监测,根据采集到的数据分析,对馆内及周边黑碳的来源、浓度建立了一个初步的环境评价,同时,对博物馆今后文物保护工作所需注意事项也提出了相应的建议。     

油母页岩废渣对大豆产量影响分析

通过实验研究了施用油母页岩废渣对大豆产量的影响,试验结果表明,施用油母页岩废渣能促进大豆生长发育,显著提高大豆产量,其中,中量油母页岩废渣21t/hm2·a配施氮磷钾化肥的效果最好,其增产率达184.03%,但随着油母页岩施用量的增加,其增产效果下降。     

MODELING THE BIG BLACK RIVER: A COMPARISON OF WATER QUALITY MODELS1

ABSTRACT: The Mississippi Department of Environmental Quality uses the Steady Riverine Environmental Assessment Model (STREAM) to establish effluent limitations. While the U.S. Environmental Protection Agency has approved of its use, questions arise regarding the model's simplicity. The objective of this research was to compare STREAM with the more commonly utilized Enhanced Stream Water Quality Model (QUAL2E). The comparison involved a statistical evaluation procedure based on sensitivity analyses, input probability distribution functions, and Monte Carlo simulation with site‐specific data from a 46‐mile (74‐km) reach of the Big Black River in central Mississippi. Site specific probability distribution functions were derived from measured rates of reaeration, sediment oxygen demand, photosynthesis, and respiration. Both STREAM and QUAL2E reasonably predicted daily average dissolved oxygen (DO) based on a comparison of output probability distributions with observed DO. Observed DO was consistently within 90 percent confidence intervals of model predictions. The STREAM approach generally overpredicted while QUAL2E generally matched observed DO. Using the more commonly assumed lognormal distribution as opposed to a Weibull distribution for two of the sensitive input parameters resulted in minimal differences in the statistical evaluations. The QUAL2E approach had distinct advantages over STREAM in simulating the growth cycle of algae.     

daNUbs: Lessons learned for nutrient management in the Danube Basin and its relation to Black Sea euthrophication

The results of the daNUbs-project deliver a basis for a proper management of nutrients in the Danube Basin. The understanding of the sources, pathways, and sinks of nutrients in the Basin and their effects on the Western ad North-Western Black Sea (WBS) ecosystem has been improved. Quantitative models on the emission of nutrients, their transport along the rivers, and their impact on the WBS have been further developed and combined. Phosphorus loads discharged by the Danube are 30-50% lower than in the 1980s (dissolved P even to a higher extent). Nitrogen emissions have decreased considerably as well. The lower nutrient discharges from the Danube have led to a significant improvement in the WBS ecosystem. Current low discharges of N and P to the WBS are the result of (1) improved nutrient removal from waste water in Germany, Austria, and Czech Republic, (2) reduced P-discharges from detergents and (3) the consequences of the economic crisis in central and eastern European countries following the political changes of 1989/1990. As the decrease is partly due to the economic breakdown in the formerly communist countries, economic development in these countries has to go along with proper nutrient management. Otherwise, the situation in the WBS ecosystem will deteriorate again.     

Adsorptive removal and recovery of the azo dye Eriochrome Black T

Bottom ash and de-oiled soya have been evaluated as potential adsorbents for the removal of a water soluble azo dye. The characterization of the adsorbents has been performed using infrared spectroscopy and differential thermal analysis. A batch of adsorption method has been adopted for studying the effects of pH, adsorbate concentration, and particle size on the adsorption process. The experimental data were tested using Langmuir, Freundlich, Tempkin, and Dubinin–Radushkevich isotherms and their parameter constants were determined. The thermodynamics showed that the process is spontaneous and exothermic. The kinetic studies revealed that the adsorption process follows first-order kinetics. A fixed-bed adsorption experiment resulted in 89% and 94% saturation of bottom ash and de-oiled soya, respectively, indicating that both adsorbents can be potentially economical.     

The costs of avoiding environmental impacts from shale‐gas surface infrastructure

Growing energy demand has increased the need to manage conflicts between energy production and the environment. As an example, shale‐gas extraction requires substantial surface infrastructure, which fragments habitats, erodes soils, degrades freshwater systems, and displaces rare species. Strategic planning of shale‐gas infrastructure can reduce trade‐offs between economic and environmental objectives, but the specific nature of these trade‐offs is not known. We estimated the cost of avoiding impacts from land‐use change on forests, wetlands, rare species, and streams from shale‐energy development within leaseholds. We created software for optimally siting shale‐gas surface infrastructure to minimize its environmental impacts at reasonable construction cost. We visually assessed sites before infrastructure optimization to test whether such inspection could be used to predict whether impacts could be avoided at the site. On average, up to 38% of aggregate environmental impacts of infrastructure could be avoided for 20% greater development costs by spatially optimizing infrastructure. However, we found trade‐offs between environmental impacts and costs among sites. In visual inspections, we often distinguished between sites that could be developed to avoid impacts at relatively low cost (29%) and those that could not (20%). Reductions in a metric of aggregate environmental impact could be largely attributed to potential displacement of rare species, sedimentation, and forest fragmentation. Planners and regulators can estimate and use heterogeneous trade‐offs among development sites to create industry‐wide improvements in environmental performance and do so at reasonable costs by, for example, leveraging low‐cost avoidance of impacts at some sites to offset others. This could require substantial effort, but the results and software we provide can facilitate the process.     

A multispecies test of source–sink indicators to prioritize habitat for declining populations

For species at risk of decline or extinction in source–sink systems, sources are an obvious target for habitat protection actions. However, the way in which source habitats are identified and prioritized can reduce the effectiveness of conservation actions. Although sources and sinks are conceptually defined using both demographic and movement criteria, simplifications are often required in systems with limited data. To assess the conservation outcomes of alternative source metrics and resulting prioritizations, we simulated population dynamics and extinction risk for 3 endangered species. Using empirically based habitat population models, we linked habitat maps with measured site‐ or habitat‐specific demographic conditions, movement abilities, and behaviors. We calculated source–sink metrics over a range of periods of data collection and prioritized consistently high‐output sources for conservation. We then tested whether prioritized patches identified the habitats that most affected persistence by removing them and measuring the population response. Conservation decisions based on different source–sink metrics and durations of data collection affected species persistence. Shorter time series obscured the ability of metrics to identify influential habitats, particularly in temporally variable and slowly declining populations. Data‐rich source–sink metrics that included both demography and movement information did not always identify the habitats with the greatest influence on extinction risk. In some declining populations, patch abundance better predicted influential habitats for short‐term regional persistence. Because source–sink metrics (i.e., births minus deaths; births and immigrations minus deaths and emigration) describe net population conditions and cancel out gross population counts, they may not adequately identify influential habitats in declining populations. For many nonequilibrium populations, new metrics that maintain the counts of individual births, deaths, and movement may provide additional insight into habitats that most influence persistence.