Abschätzung der Eignung einer molekularbiologischen Methode zur Charakterisierung der Grundwasserbiozönose

Assessing the Suitability of a Molecularbiological Method To Characterise the Microbial Populations in Groundwater A molecularbiological technique was used to characterise the bacterial community structure of groundwater habitats. This method consists of the isolation of bacterial DNA from the samples, amplification of 16S rDNA by PCR (polymerase chain reaction), and separation of the amplified DNA by DGGE (denaturing gradient gel electrophoresis). By using more specific primer combinations in the PCR instead of universal eubacterial primers, also groups of microorganisms (Proteobacteria, sulfate reducer, Archaea) were determined. The resulting DGGE patterns that reflect the microbial diversity are compared and differences or similarities evaluated. In the present studies, groundwater from different sites (bank filtrate, artificially recharged groundwater, and natural groundwater) and with changing redox milieus (aerobic, anaerobic) were investigated as well as the solid aquifer material. Besides, samples were taken from the different stages of artificial groundwater recharge, i.e., from surface water to the drain tile. Samples from groundwater derived from sites with different hydrogeochemical or hydrological conditions like bank filtrate and recharged groundwater revealed great differences in DGGE patterns indicating a characteristic species composition in these habitats, while samples taken at different times from the same groundwater showed only small seasonal variations. Clearly different patterns were also found for groundwater and the adjacent solid material as well as for anaerobic and aerobic groundwaters. Looking at artificial groundwater recharge, almost identical patterns were found in raw water and samples from gravel and sand filtration. DGGE patterns from the resulting groundwater indicated a total change in community structure during underground passage. By using group specific primers, Desulfovibrionaceae, Desulfobacteriaceae, and Archaea could be detected in anaerobic groundwaters.The molecularbiological approach described here gives an increasingly comprehensive and more precise picture of the microbial population of different environments. It is especially suitable to compare the community structure from different habitats or to analyse changes for example due to environmental stress at the same site.     

Melt water chemistry and its impact on stream water quality

Samples of snowpack leachate were collected over a 60 day period of the spring melt season in 1988 and 1989 at a 10 km² upland catchment in the Cairngorm mountains of Scotland. These were analysed for major ions to assess snowpack chemistry dynamics through the spring and to assess the melt water influence on stream water chemistry. The data clearly show preferential elution of sulphate and nitrate over chloride and hydrogen over the other cations during the early melt of 1988. Following the addition of ions to the snow surface, either as snow or later in the season as rain, the elution sequence is reproduced. Comparison of leachate chemistry with stream chemistry samples taken at the basin outlet indicate that snow pack melt water contributes directly to stream water. The stream water chemistry signal is, however, noisy and the stream concentrations are considerably damped relative to the snowpack leachate. This is thought to be a consequence of differential melting within the catchment as the snowpack at lower altitudes is at a more advanced stage of melt and so holds fewer solutes and mixing with groundwater contributions. Temperature observations at different altitudes within the catchment support this interpretation.     

Characterization and identification of na-cl sources in ground water

Elevated concentrations of sodium (Na+) and chloride (Cl-) in surface and ground water are common in the United States and other countries, and can serve as indicators of, or may constitute, a water quality problem. We have characterized the most prevalent natural and anthropogenic sources of Na+ and Cl- in ground water, primarily in Illinois, and explored techniques that could be used to identify their source. We considered seven potential sources that included agricultural chemicals, septic effluent, animal waste, municipal landfill leachate, sea water, basin brines, and road deicers. The halides Cl-, bromide (Br), and iodide (I) were useful indicators of the sources of Na+-Cl- contamination. Iodide enrichment (relative to Cl-) was greatest in precipitation, followed by uncontaminated soil water and ground water, and landfill leachate. The mass ratios of the halides among themselves, with total nitrogen (N), and with Na+ provided diagnostic methods for graphically distinguishing among sources of Na+ and Cl- in contaminated water. Cl/Br ratios relative to Cl- revealed a clear, although overlapping, separation of sample groups. Samples of landfill leachate and ground water known to be contaminated by leachate were enriched in I and Br; this provided an excellent fingerprint for identifying leachate contamination. In addition, total N, when plotted against Cl/Br ratios, successfully separated water contaminated by road salt from water contaminated by other sources.     

Variability in Bacteria and Virus‐Like Particle Abundances During Purging of Unconfined Aquifers

Standard methodologies for sampling the physicochemical conditions of groundwater recommend purging a bore for three bore volumes to avoid sampling the stagnant water within a bore and instead gain samples representative of the aquifer. However, there are currently no methodological standards addressing the amount of purging required to gain representative biological samples to assess groundwater bacterial and viral abundances. The objective of this study was to examine how bacterial and viral abundances change during the purging of bore volumes. Six bores infiltrating into unconfined aquifers were pumped for five or six bore volumes each and bacteria and virus‐like particles (VLPs) were enumerated from each bore volume using flow cytometry. In examination of the individual bores trends in bacterial abundances were observed to increase, decrease, or remain constant with each purged bore volume. Furthermore, triplicates taken at each bore volume indicated substantial variations in VLP and bacterial abundances that are often larger than the differences between bore volumes. This indicates a high level of small scale heterogeneity in microbial community abundance in groundwater samples, and we suggest that this may be an intrinsic feature of bore biology. The heterogeneity observed may be driven by bottom up processes (variability in the distribution of organic and inorganic nutrients), top‐down processes (grazing and viral lysis), physical heterogeneities in the bore, or technical artifacts associated with the purging process. We suggest that a more detailed understanding of the ecology underpinning this variability is required to adequately describe the microbiological characteristics of groundwater ecosystems.     

安徽升金湖越冬白头鹤（Grus monacha）肠道菌群组成的时间变化

肠道微生物对于维持动物消化道内环境的稳定具有重要意义,而肠道微生物菌群结构也受寄主食物成份等外界环境因素的影响.研究动物肠道微生物菌群结构可以更好地了解动物生活状况.以升金湖越冬白头鹤的粪便作为研究对象,以微生物16S rRNA的V3~V4区作为标记基因,进行高通量测序,分析升金湖越冬不同时期白头鹤肠道菌群结构的差异性.研究结果表明:升金湖越冬期不同时期白头鹤粪便样品中微生物多样性指数如香农威纳多样性指数和辛普森指数无显著性差异.但是越冬期不同阶段的粪便样品中菌群组成存在差异,主要包括:在门分类水平,越冬前期拟杆菌门含量较高,厚壁菌门含量较中后期低;越冬中期放线菌门含量较高;越冬后期变形菌门含量较高.在属分类水平,相对于其他两个时期,越冬前期普氏菌属(Prevotella)含量较高,越冬中期杆菌属(Lysinibacillus)含量较高,越冬后期梭菌属(Clostridium)含量较高,并且普氏菌属含量从越冬前期到中期、再到后期有明显的下降趋势,而梭菌属含量从越冬前期到中期、再到后期有明显的升高趋势.这些结果表明不同越冬时期白头鹤肠道菌群组成不同,越冬期不同阶段的食物变化可能作为一个影响因素.     

Fate of Lignin in the Process of Aerobic Biological Treatment of Paper Mill Wastewater

Although lignin is known to be not readily biodegradable the concentration of dissolved lignin decreased during aerobic biological treatment of paper mill wastewater performed in sequencing batch reactors (SBR). Systematic lab scale batch tests were conducted to clarify whether the observed removal of lignin was the result of biodegradation or adsorption onto the activated sludge. For the batch tests, sludge samples were taken from sequencing batch reactors operated at solid retention times (SRT) of 10, 15, 20, 30, and 40 days, respectively. The amount of lignin present in the bulk liquid and in the sludge samples was quantified by an analytical procedure comprising pyrolysis, gas chromatography and mass spectrometry (py‐GC/MS analysis). It was found that lignin adsorbs onto the activated sludge by up to 30%[TH]w/w. This demonstrates the sludge excellent adsorption properties. The ultimate removal of lignin is achieved by sludge wasting. The highest overall removal rate was found when sludge was used from the SBR run at SRT of 20 days.     

Landfill Leachate Treatment: A Case Study for Istanbul City

One of the most important problems arising from landfilling solid wastes is the leachate which contains high amount of pollution. Discharge of leachate without treatment causes negative effects on environmental and public health. In this study, parameters of chemical oxygen demand (COD), total nitrogen (TN), ammonia nitrogen (NH₄‐N), and total phosphorus (TP) were examined in the samples taken from the influent and effluent of leachate treatment plant, where Odayeri landfill leachate is treated. Obtained results showed that the treatment plant, which consisted of preanoxic biological treatment system, ultrafiltration (UF) and nanofiltration (NF) units were operating with high efficiency. Among the examined parameters during study, COD, TN, NH₄‐N, and TP were found to be treated at the rate of 99, 94.5, 99, and 93.8%, respectively. Landfilling is increasing rapidly in the world and this consequently brings the need of leachate treatment facilities. Therefore, this study is considered to be a guide for construction and operation stages of proposed new treatment plants.     

Emerging Contaminants at a Closed and an Operating Landfill in Oklahoma

Landfills are the final depositories for a wide range of solid waste from both residential and commercial sources, and therefore have the potential to produce leachate containing many organic compounds found in consumer products such as pharmaceuticals, plasticizers, disinfectants, cleaning agents, fire retardants, flavorings, and preservatives, known as emerging contaminants (ECs). Landfill leachate was sampled from landfill cells of three different age ranges from two landfills in Central Oklahoma. Samples were collected from an old cell containing solid waste greater than 25 years old, an intermediate age cell with solid waste between 16 and 3 years old, and operating cell with solid waste less than 5 years old to investigate the chemical variability and persistence of selected ECs in landfill leachate of differing age sources. Twenty‐eight of 69 analyzed ECs were detected in one or more samples from the three leachate sources. Detected ECs ranged in concentration from 0.11 to 114 μg/L and included 4 fecal and plant sterols, 13 household\industrial, 7 hydrocarbon, and 4 pesticide compounds. Four ECs were solely detected in the oldest leachate sample, two ECs were solely detected in the intermediate leachate sample, and no ECs were solely detected in the youngest leachate sample. Eleven ECs were commonly detected in all three leachate samples and are an indication of the contents of solid waste deposited over several decades and the relative resistance of some ECs to natural attenuation processes in and near landfills.     

Statistical Comparison of Leachate from Hazardous, Codisposal, and Municipal Solid Waste Landfills

There has been considerable debate regarding the chemical characterization of landfill leachate in general and the comparison of various types of landfill leachate (e.g., hazardous, codisposal, and municipal) in particular. For example, the preamble to the U.S. EPA Subtitle D regulation (40 CFR Parts 257 and 258) suggests that there are no significant differences between the number and concentration of toxic constituents in hazardous versus municipal solid waste landfill leachate. The purpose of this paper is to statistically test this hypothesis in a large leachate database comprising 1490 leachate samples from 283 sample points (i.e., monitoring location such as a leachate sump) in 93 landfill waste cells (i.e., a section of a facility that took a specific waste slream or collection of similar waste streams) from 48 sites with municipal, codisposal, or hazardous waste site histories. Results of the analysis reveal clear differention between landfill leachate types, both in terms of constituents detected and their concentrations. The result of the analysis is a classification function that can estimate the probability that new leachate or ground water sample was produced by the disposal of municipal, codisposal, or hazardous waste. This type of computation is illustrated, and applications of the model to Superfund cost-allocation problems are discussed.     

Ship board testing of a deoxygenation ballast water treatment

A ship board trial of a deoxygenation method for treating ballast water was carried out during a voyage from Southampton (United Kingdom) to Manzanillo (Panama). A nutrient solution added to two ballast tanks encouraged bacterial growth, resulting in a gradual change to an anoxic environment. Samples were taken from two treated tanks and two untreated tanks to assess changes in the abundance and viability of zooplankton, phytoplankton and bacteria. The work was carried out before the International Maritime Organization (IMO) standard was agreed so only a broad indication of whether the results achieved the standard was given. For the zooplankton, the standard would have been achieved within 5 or 7 days but the phytoplankton results were inconclusive. The biological efficacy was the result of the combination of several factors, including the treatment, pump damage and an increase in the water temperature during the voyage.     

Preliminary study on responses of marine nematode community to crude oil contamination in intertidal zone of Bathing Beach, Dalian

This study investigated the responses of marine nematodes to crude oil contamination in polluted and relatively uncontaminated sites in Dalian Xingang, China, 40 days after an oil spill. Samples were taken at different tide levels on the beach and at different positions along the beach. We present the results of a comparison of nematode assemblages from undisturbed sediment from the Xiajiahezi Bathing Beach with those from sediment from the Xinghai Bathing Beach contaminated with crude oil. A total of 1666 nematodes from 26 genera were found in this study. Results showed significant differences in nematode assemblages between samples from undisturbed controls and those from the polluted area. Nematode abundance, number of species, diversity and species richness decreased significantly with increasing levels of crude oil contamination. Fifteen genera were eliminated and seemed to be composed of species intolerant to crude oil contamination; only the abundance of Marylynnia sp. increased slightly.     

Anwendung einfacher Konservierungsverfahren für Wasseruntersuchungen

Samples taken from the influent and effluent of a biological wastewater treatment plant were immediately analysed and investigated at different intervals within four weeks after sampling. They were stored in the dark at 277 and 293 K and at pH 2 and pH 12 each. None of the measures resulted in a correct stabilization or preservation of the samples: orthophosphate cannot be stabilized by any measure, the total phosphate needs not be stabilized, the COD gives values which are still useful only at pH 2 and 277 K, TOC and DOC do not show useful results with none of the applied techniques, equally insufficient are the results for ammonium- and nitrate-ions. In addition, differences occur in the behaviour of the samples taken from the influent and effluent. In agreement with the results published in the literature, the chemical analysis has to be carried out within 6 h after sampling.     

Comparison of Downhole and Surface Sampling for the Determination of Volatile Organic Compounds (VOCs) in Ground Water

The relative precision and accuracy of sampling and analysis methods for the determination of trace concentrations of volatile organic compounds (VOCs) in ground water were compared. Samples were collected from a well containing nanogram-per-liter (ng/L) to microgram-per-liter (μg/L) levels of VOCs. A Keck helical rotor submersible pump was used to collect samples at the surface for analysis by purge and trap (P&T) and for analysis by adsorption/thermal desorption (ATD). Downhole samples were collected by passing water through an ATD cartridge. Although slight spontaneous bubble outgassing occurred when the water was brought to the surface, the relative precisions and comparabilities of the surface and downhole methods were generally found to be equivalent from a statistical point of view. A main conclusion of this study is that bringing sample water to the surface for placement in VOC vials (and subsequent analysis by P&T) can be done reliably under many circumstances. However, care must still be taken to prevent adsorption losses and cross contamination. Samples subject to strong bubble outgassing will need to be handled in a special fashion (e.g., by downhole ATD) to minimize volatilization losses. Additionally, the higher sensitivity of the ATD method allows lower detection limits than are possible with P&T. For example, several compounds present at the ng/L level could be determined with confidence by ATD, but not by P&T.     

Elements in Cottonwood Trees as an Indicator of Ground Water Contaminated by Landfill Leachate

Ground water at the Norman Landfill Research Site is contaminated by a leachate plume emanating from a closed, unlined landfill formerly operated by the city of Norman, Oklahoma, Ground water contaminated by the leachate plume is known to be elevated in the concentration of many, organic and inorganic constituents. Specific conductance, alkalinity, chloride, dissolved organic carbon, boron, sodium, strontium, and deuterium in ground water are considered to be indicators of the leachate plume at this site.
Leaf samples of broad-leafed cottonwood, Populus deltoides , were collected from 57 sites around the closed landfill. Cottonwood, a phreatophyte or "well plant," functions as a & surrogate well and serves as a ground water quality sampler. The leaf samples were combusted to ash and analyzed by instrumental neutron activation for 35 elements and by prompt-gamma instrumental neutron activation, for boron. A monitoring well was located within a few meters of a sampled cottonwood tree at 15 of the 57 sites, and ground water samples were collected from these monitoring wells simultaneously with a leaf sample. The chemical analyses of the ground water and leaf samples from these 15 sites indicated that boron, bromine, sodium, and strontium concentrations in leaves were significantly correlated with leachate indicator constituents in ground water. A point-plot map of selected percentiles indicated high concentrations of boron, bromine, and sodium in leaf ash from sites downgradient of the most recent landfill and from older landfills nearby.
Data from leaf analysis greatly extended the known areal extent of the leachate plume previously determined from a network of monitoring wells and geophysical surveys. This phytosgeochemical study provided a cost-effective method for assessing the extent of a leachate plume from an old landfill. Such a method may be useful as a preliminary sampling tool to guide the design of hydrogeochemical and geophysical studies.     

Darstellung der mikrobiellen Besiedlungsstruktur verschiedener Grundwasserhabitate durch Anwendung molekularbiologischer Methoden

Community Structures of Different Groundwater Habitats Investigated Using Methods of Molecular Biology The degradation of pollutants in groundwater and aquifers depends on microbiological and hydrogeochemical processes. To understand the transport and fate of anthropogenic compounds during bank filtration and artificial recharge of groundwater it is necessary to gain more information about the structure of microbial populations in these systems. The population structure of aerobic, anaerobic groundwater habitats and of water samples during artificial groundwater recharge was examined by 16S rDNA based analysis. Water and sediment samples were collected from a groundwater catchment area with artificial groundwater recharge near the river Ruhr in NW-Germany. 16S rRNA genes of mixed bacterial DNA from different samples were amplified by PCR (polymerase chain reaction) with eubacterial primer sequences. To reveal eubacterial population structure amplified PCR-products were separated by DGGE (denaturing gradient gel electrophoresis) on the basis of melting domain structure and nucleotide composition. DGGE patterns of groundwater enrichment cultures and groundwater samples were compared to demonstrate differences between the use of cultivation dependent and molecularbiological approaches. The DGGE pattern of groundwater is very complex and differs significantly from DGGE patterns of groundwater enrichment cultures characterized by a small number of distinct bands. This shows the small quantity of culturable microorganisms in groundwater eco-systems. Aerobic and anaerobic groundwater and sediment samples differ markedly in their DGGE profiles. Different hydrogeochemical zones of this groundwater catchment area are mirrowed by distinct DGGE patterns indicating changes in microbial community structure.Analysis of bacterial population structure in the course of artificial groundwater recharge shows identical DGGE patterns comparing surface water samples to samples taken be-fore gravel prefiltration and before sand filtration. In contrast the DGGE pattern of artificial recharged groundwater differs markedly, indicating significant changes in microbial population during underground passage.     

Observations on the biota of an estuarine beach at Hardys Bay (NSW, Australia) following a spillage of aldrin

An industrial accident resulted in a spillage of aldrin onto an estuarine beach at Hardys Bay, New South Wales. Samples of water and sediment were taken 3 weeks later to measure the level of contamination resulting from the spill. The abundances of some intertidal biota were also determined at the site of the spillage and in other uncontaminated areas.

Three weeks after the spill, samples of water were not contaminated by aldrin but samples of sediment from the surface in the vicinity of the drain contained aldrin. In comparison to uncontaminated locations the abundances of crustacea were greatly reduced in the vicinity of the drain but abundances of polychaetes were not significantly different. The field data on the relative susceptibility of the two groups of animals agrees well with laboratory derived LC50 data for crustacea and polychaetes.

The study suggests that degree of contamination of water and sediment may not always be an accurate reflection of acute impact on biota, and that different components of the biota can show different reactions to the presence of a toxic chemical.     

Multilevel samplers as microcosms to assess microbial response to biostimulation

Passive multilevel samplers (MLS) containing a solid matrix for microbial colonization were used as in situ microcosms in conjunction with a push-pull biostimulation experiment designed to promote biological U(VI) and Tc(VII) reduction. MLS were deployed at 24 elevations in the injection well and two downgradient wells to investigate the spatial variability in microbial community composition and growth prior to and following biostimulation. The microbial community was characterized by real-time quantitative polymerase chain reaction (Q-PCR) quantification of bacteria, NO(3)(-)-reducing bacteria (nirS and nirK), delta-proteobacteria, Geobacter sp., and methanogens (mcrA). Pretest cell densities were low overall but varied substantially with significantly greater bacterial populations detected at circumneutral pH (t-test, alpha= 0.05), suggesting carbon substrate and low pH limitations of microbial activity. Although pretest cell densities were low, denitrifying bacteria were dominant members of the microbial community. Biostimulation with an ethanol-amended ground water resulted in concurrent NO(3)(-) and Tc(VII) reduction, followed by U(VI) reduction. Q-PCR analysis of MLS revealed significant (1 to 2 orders of magnitude, Mann-Whitney U-test, alpha= 0.05) increases in cell densities of bacteria, denitrifiers, delta-proteobacteria, Geobacter sp., and methanogens in response to biostimulation. Traditionally, characterization of sediment samples has been used to investigate the microbial community response to biostimulation; however, collection of sediment samples is expensive and not conducive to deep aquifers or temporal studies. The results presented demonstrate that push-pull tests with passive MLS provide an inexpensive approach to determine the effect of biostimulation on contaminant concentrations, geochemical conditions, and the microbial community composition and function.     

Clionid sponge surveys on the Florida Reef Tract suggest land-based nutrient inputs

Bioerosion by Cliona delitrix and Cliona lampa was assessed at 43 sites along the Florida Reef Tract, USA, in the summer of 2001. Sponge abundances were estimated using rapid visual assessment. Tissue samples of sponges were taken for analysis of delta15N. Comparison samples were taken from Belize. Annual trends in sponge abundance were estimated from archived videos covering the period from 1996 to 2001. Sites with the greatest boring sponge size and cover were in the Backcountry and Lower Keys, where total nitrogen, ammonium, and delta15N levels were highest. The sites with the largest relative increase of C. delitrix and C. lampa over the 5 year period were in the Upper Keys, where the greatest relative decline in stony coral cover has occurred. Florida sponge delta15N values were 5.2(+/-0.1)%, suggesting the influence of human waste; in comparison, offshore Belize samples were 2.1(+/-0.1)%. These results suggest sewage contamination of the Florida Reef Tract, shifting the carbonate balance from construction to destruction.     

Small-scale spatial variation of benthic algal assemblages in a peat bog

Spatial patterns on a very small scale (10 cm), and the effect of artificial barriers on the composition of phytobenthic algal assemblages along two transects within different microhabitat types were investigated. Samples were taken in a peat bog along linear transects on a scale of 10 cm, and water chemistry was examined. The distribution of algae along both transects was influenced by both spatial distance and environmental conditions in similar proportions. Differences in species composition in various parts of the transects were observed, but this pattern was primarily related to the abundance of species, rather than to their presence/absence in samples. Similarity in species composition correlated with spatial distance and environmental parameters in both microhabitat types. I concluded that, given a homogenous environment on a small scale, spatial distribution of algae is affected by both the environmental conditions of the microhabitats and their dispersal limitations. Moreover, an artificial barrier constituted an obstruction for water and nutrient flow, as well as algal migration, and had an impact on species composition.     

Impact of anthropogenic activities on the sediment microbial communities of Baiyangdian shallow lake

Microorganisms are recognized as sensors of external disturbance in freshwater ecosystems.In this study,sediment samples from regions with strong human activity interference(four sites),moderate human activity interference(five sites) and minor human activity interference(five sites) in Baiyangdian Lake were collected;and their physiological and chemical properties and heavy metals contents were analyzed.The structures of bacterial and fungal communities were tested using 16 S ribosomal Ribonucleic Acid(rRNA) and Internal Transcribed Spacer 2(ITS2) high-throughput sequencing technologies.The results indicated that Proteobacteria was the most abundant bacterial phylum.Ascomycota,Basidiomycota and Ciliophora were the dominant phyla of fungi.Obvious differences of microbial genera among the three regions we re obse rved,especially fungal genera.With intensified disturbance by human activities,the Simpson and Shannon indices of bacteria significantly decreased.The fungal communities were clustered into three groups in accordance with the different human disturbance levels.The bacterial communities of sediment samples under moderate and minor human disturbance appeared similar,but different from those under strong human disturbance.Redundancy analysis indicated that zinc,total phosphorus,copper,and lead were the dominant factors that influenced the bacterial community.Nitrifiers and sulfate-reducing bacteria were influenced by pH,nitrate(NO3),and total nitrogen.The fungal community was significantly affected by total phosphorus.This study reveals that sediment microbial community structures among different regions of a shallow lake are mainly impacted by human activities.