Nährstoff- und Sauerstoffbilanz eines hochbelasteten Klärwerksableiters unter besonderer Berücksichtigung der submersen Makrophyten

Nutrient and Oxygen Balance of a Highly Polluted Treated Sewage Channel with Special Regard to the Submerged Macrophytes The changes of the concentrations of inorganic nitrogen compounds, orthophosphate, and oxygen were measured in the flowing wave along the flowing stretch of the Berlin treated sewage channel Wuhle monthly over a period of two years (1993/94) to estimate the nutrient and oxygen balances. This treated sewage channel is rich in nutrients and densely covered with submerged macrophytes. During the period of investigation in 1993 (1994), the effluent of the sewage treatment plant Falkenberg, which is lacking in adjustable nitrification and denitrification. contained in average 16.1 (12.7) mg/L of NH-N, 13.7 (9.4) mg/L of NO₃^?-N. 0.94 (0.69) mg/L of NO-N. and 0.36 (0.26) mg/L of PO-P. Due to the neglectable influence of other processes like nutrient uptake by submerged macrophytes and algae, desorption of ammonia or dilution, the changes of the concentrations of the inorganic nitrogen compounds are mainly influenced by nitrification and denitrification. The nitrification is mainly done by sessile nitrifiers in the treated sewage channel Wuhle. The nitrification rates. calculated from the decrease of the ammonium concentrations, were between 0.5 and 20 g/(m²d) related to the flowing stretch area. The ammonium concentrations decreased along the flowing stretch in average by 20 to 44%. The highest nitrification rates could be found at the stretches with a dense colonization with submerged macrophytes and a good oxygen supply due to low water depth and high flowing velocities. The denitrification rates, calculated from the decrease of the total of the concentrations of the inorganic nitrogen compounds, were between 0.5 and 23 g/(m²d) related to the flowing stretch area. The total loss of nitrogen due to denitrification was between 10 and 20% along the flowing stretch of the treated sewage channel Wuhle. This corresponds to a total amount of up to 530 kg nitrogen per day. The main part of the phosphorus occured as orthophosphate in concentrations between 0.04 and 0.87 mg/L of PO-P in the effluent of the treatment sewage plant Falkenberg. The orthophosphate concentration changed along the flowing stretch mostly in such a manner that it were at the same level at the end of the flowing stretch at the mouth into the river Spree. The self-purification capacity of the channel does not lead to a relevant reduction of the very high nutrient load under the present conditions. The rates of the photosynthetic production (P) and the community respiration (R) were calculated from the rates of the total changes of oxygen with regard to the physical aeration. The rates of the photosynthetic production were between 0 and 33 g/(m²d), the rates of the community respiration between 15 and 75 g/(m²d). Therewith, the Wuhle treatment sewage channel belongs to the very productive waters. A positive balance (P > R) could only be measured on two segments in May. The rates of oxygen production depend on the ratio width to depth of the water. It is possible that the positive influence of the submerged macrophytes on the oxygen balance also at higher biomasses than 250 g/m² (as dry weight) predominates at the segments with a favourable ratio. The portion of the oxygen input through diffusion along the flowing stretch and at the weirs was 30%, respectively, that of the photosynthic production 40% in summer. The rates of community respiration decreased along the flowing stretch by 50 to 90%. The nitrification had the main portion of the oxygen depletion in the Wuhle treated sewage channel with 60…80%. Despite the high biomass, the respiration of the submerged macrophytes had only a small portion of the total oxygen depletion. Nevertheless, the submerged macrophytes contributed to the nearly total oxygen depletion at the most densely covered segment 2 at night. The decrease of the content of particular organic material and the ammonia concentrations at the effluent of the sewage treatment plant, a diminishing of the biomass of submerged macrophytes by shading, and the widening of a few flowing stretches are demanded for the improvement of the oxygen balance of the Wuhle treated sewage channel.     

脱脂、磷化污水的化学治理

本文研究了脱脂、磷化污水的水质状况，通过去除主要污染物质的化学方法，试剂用量，综合效果等优选，提出最佳的污水治理工艺流程，工程运转后，证明经治理后的排放水均达到国家允许排放的一级标准。     

Analysis of multiple enteric viral targets as sewage markers in coral reefs

Water and coral mucus samples were collected from throughout the Florida Keys National Marine Sanctuary and the Dry Tortugas for three years and were analyzed for human enteric viruses (enteroviruses, noroviruses, hepatitis A virus and adenoviruses) as conservative markers of human sewage using molecular methods. Of the 100 coral and water samples collected, 40 contained genetic material from one or more human enteric viruses. DNA-based adenoviruses were detected widely, in 37.8% of samples and at 91% of stations, including ‘pristine’ reefs in the Dry Tortugas; however, the detection rate was 12% for the RNA-based enteroviruses and noroviruses (hepatitis A virus was never detected). The disparity between the prevalence of RNA- and DNA-based viruses suggests the need for additional work to determine the utility of adenovirus as marker of human sewage.     

基于VirtualGIS技术的龙口市流域综合治理研究

将虚拟再现技术、地理信息系统技术、遥感技术集成在一起构建虚拟再现地理信息系统，通过对不同时期流域地理环境的虚 拟再现，追踪其演化过程和认识其存在的问题，经过三维建模分析，提出流域综合治理措施，并对预期治理效果进行预测与分析。     

Wheat as food, wheat as industrial substance; comparative geographies of transformation and mobility

Wheat is the world’s second largest crop, supplies 19% of human calories, and is the largest volume crop traded internationally. Its uniquely malleable physical properties make it a valued industrial substance, albeit often an invisible one, as well as a food. This combination of transformation, invisibility and mobility demands new ways of thinking about wheat geographies. In this paper we document and analyse several ‘moments’ in the life of Australian wheat; at the supermarket, in the lives of coeliac sufferers, in laboratories, industrial factories and on the farm. We illustrate diverse patterns of interaction with wheat. The major plane of differentiation is between wheat as food and wheat as industrial substance. The explicit connection of food to the human body tends to fix the identity of wheat, whether as healthy staple of the nation, or harmful poison to coeliacs who must negotiate its presence using the regulatory regime of food labelling. This is no small task given the ubiquity of wheat; our survey of 10,235 supermarket items found it in 29.5% of labelled food items. In contrast, when wheat is physically and chemically disassembled to become an industrial substance, its presence and identity become mutable, hidden and often invisible.     

黄土特性及处理方法研究

本文介绍了不同时代、不同地貌区黄土的物理力学性质指标的差异,通过研究黄土湿陷性指标及其相关指标,准确判定黄土的湿陷性等级,从而选用合适的处治方法有效的消除黄土湿陷性对工程的危害。     

Reduzierung von Bakterien- und Coliphagen-Konzentrationen auf der Fließstrecke eines Klärwerksableiters

Reduction of the Concentration of Bacteria and Coliphages along the Flowing Stretch of a Treated Sewage Channel The efficiency of surface waters to eliminate E. coli, fecal streptococci, Salmonella spp., and coliphages was evaluated in a small river which receives treated wastewater and which is rich in submerged macrophytes. The study took place between April and December, 1994. Total colony count, BOD₅, O₂ concentration and water temperature were determined in the river as well. As the river does not receive additional water downwards along its 17.2 km course, dilution effects could be ruled out as the cause for the elimination of the microorganisms. The reduction is assumed to happen rather due to sedimentation, grazing, and adsorption to the submerged waterplants. Immediately after discharge of the wastewater, the river water contained about 10⁵ cfu/100 mL E. coli and 10⁴ cfu/100 mL fecal streptococci, about 1000 pfu/100 mL coliphages, and, as a rule, was positive for salmonella in 10 mL. The reduction of E. coli, fecal streptococci, salmonella, clostridia, and coliphages at the end of the course was 1 to 2 orders of magnitude. This reduction took place mainly within the first 4.7 km, a part in which, due to low flowing velocities, suspended solids settle down efficiently. Besides, at the end of this part the submerged waterplants are especially abundant. The reduction of suspended solids correlated positively with that of BOD₅, bacteria, and coliphages. The reduction of microorganisms was not sufficient to fulfill the requirements of the European Community guidelines for bathing waters and for surface waters used as drinking water source. The regenerating capacity of surface waters is not sufficient to eliminate pathogens from convenionally treated wastewater. Therefore, tertiary treatment is necessary to keep receiving waters reasonably free from pathogens.     

Plant species as indicators of geochemical anomalies: Experiences onIlex aquifolium (holly)

The distribution of Zn, Cd, Pb, and Cu, in plants growing in mineralized and sterile areas of Tuscany has been studied to verify if and to what extent metalaccumulating species represent evidence of geochemical anomalies in soils. Samples of leaves and twigs from trees were collected, and analyzed by means of differential pulse anodic stripping voltammetry (DPASV). Hollies, brambles, and Holm oaks in particular were considered in the mineralized area of Bottino, and the special aptitude of hollies in concentrating Cd with respect to the other metals has been verified. Cadmium has been previously recognized as a pathfinder for zinc ore bodies; the results of this investigation appear to point out the relevance of holly as a bioindicator of geochemical zinc anomalies. Lower metal concentration characterizes the same species from other mineralized and sterile zones, with the exception of the urbanized area of Florence, where relatively higher Zn concentrations in hollies appear to be due to atmospheric pollution.     

A survey of the non-marine Cretaceous in China

A review of the stratigraphy of the continental Cretaceous sequences is given. Conchastracans, ostracods and charophytes have proved useful in biostratigraphy, with additional aid from pelecypods, gastropods, larger plant fossil and, locally, dinosaur remains.The continental Lower Cretaceous deposits are considered to fall into three domains: the Circum-Pacific, the Tethyan and the NW Chinese. The continental Upper Cretaceous sediments occur mainly in the three domains: NW Chinese, SE Chinese and NE Chinese.     

Relationship of chemical fractions of heavy metals with microbial and enzyme activities in sludge and ash-amended acid lateritic soil from India

The influence of metals, Cd, Cr, Cu, Ni, Pb and Zn, on the microbial biomass and enzyme activities of an amended acid lateritic soil were investigated under field conditions receiving a one-time application of 52 t ha^–1 of sludge, coal ash and their mixtures at 1:3, 1:1 and 3:1 proportions, and including control and chemical fertilizer treatment at crop-specific recommended doses. Paddies and peanuts were grown in the experimental plots and soil was sampled twice after 6 months and 1 year after amendment application. The heavy metals in the soil were fractionated using sequential extraction and the increments in their concentrations in amended soil with respect to the control were determined. Concentrations of Cd, Ni and Zn were determined to have increased in their mobile fractions and were more pronounced in soil collected during the second sampling, which was associated with a decrease in soil organic carbon. The size of the microbial biomass carbon and the soil enzyme activities increased with the addition of an amendment and was highest at equal proportions of coal ash and sludge. Further increase in the proportion of sludge resulted in a significant decrease in biomass carbon. Simple correlation revealed significant and strong negative relations of mobile fractions of Cd and Ni with the ratio between microbial biomass C and organic carbon in soil, while the organic carbon content and the pH were positively correlated. The microbial activities were determined to be sensitive to the concentrations of some heavy metals in mobile fractions and therefore indicated possibilities of being useful as indicators for evaluation of toxic effects of sludge-borne metals on soil organisms.