Field Investigations on Sediment Occurrence and Behaviour in Brussels Combined Sewers

1992 ◽  
Vol 25 (8) ◽  
pp. 71-82 ◽  
Author(s):  
M. Verbanck
Keyword(s):  
Drainage System ◽  
Solid Material ◽  
Field Studies ◽  
Main Trunk ◽  
Limited Mobility ◽  
Sediment Bed ◽  
Research Activities ◽  
Field Investigations ◽  
Dry Spells ◽  
Receiving Waters

Although sewer sediments are now widely recognized as a major source of misfunction of urban drainage systems (for both hydraulic and environmental considerations), it is still too infrequent that priority of research activities in this area is given to field studies. The measuring campaigns conducted since 1986 in the drainage system of Brussels-North have been focused on sedimentation processes in the major sewer lines. There is an obvious distinction to be made between solids constituting the sediment bed of a man-entry sewer, which are relevant for its hydraulic capacity, and the ones contributing to the pollutional impact of CSOs upon receiving waters. The material which is removed several times a year from the main trunk sewer of Brussels is coarse, granular and has a low environmental impact, notably because of its limited mobility. This appears to be due to a very efficient granulometric grading, as a result firstly of the retention of the coarsest solids in highly selective gully-pot inlets, and secondly of an elutriation process removing from the sediment bed all fine organic-rich particles during daily peak flows. There is evidence to show that the build-up of the sediment bed in these large-sized sewers is driven by a bed-load process (active even during dry spells), while the solid material responsible for the detrimental effects of CSOs (which is much finer) is primarily transported through wash-load and suspended-load.

Use of Biomonitoring to Control Toxics in the United States

1988 ◽  
Vol 20 (10) ◽  
pp. 101-108 ◽  
Author(s):  
Nelson A. Thomas
Keyword(s):  
Water Quality ◽  
Chronic Toxicity ◽  
National Policy ◽  
Single Species ◽  
Field Studies ◽  
The United States ◽  
Toxicity Tests ◽  
Toxic Pollutants ◽  
Receiving Waters ◽  
Biological Field

A biomonitoring program has been developed in support of the National Policy for the Development of Water Quality-Based Permit Limitations for Toxic Pollutants. The program focuses on the use of laboratory toxicity tests on aquatic plants and animals to predict ecosystem impact caused by toxic pollutants. Both acute and chronic toxicity tests were developed to test effluents and ambient waters. Laboratory and biological field studies were conducted at nine sites. Single species laboratory toxicity tests were found to be good predictors of impacts on the ecosystem when two or more species were used. Biomonitoring can be undertaken either on effluents and/or on the receiving waters. In that toxicity related to seeps, leachates and storm sewers has often been found upstream from dischargers, it is beneficial to conduct both effluent and ambient biomonitoring.

Comprehensive Planning of Urban Drainage and Wastewater Treatment

1993 ◽  
Vol 27 (12) ◽  
pp. 205-208
Author(s):  
Dirk-Th Kollatsch
Keyword(s):  
Wastewater Treatment ◽  
Transport Model ◽  
Drainage System ◽  
Simulation Models ◽  
Urban Drainage ◽  
Sewer Systems ◽  
Priority Task ◽  
Treatment Facilities ◽  
Receiving Waters ◽  
Pollution Impacts

For upgrading the urban drainage system (UDS) the reduction of pollution impacts is the priority task concerning the environmental protection of the receiving waters. With simulation models the interactions between surface, sewer systems, overflow structures and treatment facilities within the UDS can be shown. Models to simulate the pollutant impacts, transport and the effects on the receiving waters are available. In a first step a pollutant transport model of sewer systems and a model to simulate the wastewater treatment processes are connected. With these models the efficiency of upgrading measures can be checked in all parts of urban drainage systems.

scholarly journals Rabies in Our Neighbourhood: Preparedness for an Emerging Infectious Disease

Pathogens ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 375
Author(s):  
Michael P. Ward ◽  
Victoria J. Brookes
Keyword(s):  
Infectious Disease ◽  
Southeast Asia ◽  
Field Studies ◽  
Emerging Infectious Disease ◽  
Disease Response ◽  
Canine Rabies ◽  
Research Activities ◽  
Potential Reservoir ◽  
Modelling Studies ◽  
Sociological Studies

Emerging infectious disease (EID) events have the potential to cause devastating impacts on human, animal and environmental health. A range of tools exist which can be applied to address EID event detection, preparedness and response. Here we use a case study of rabies in Southeast Asia and Oceania to illustrate, via nearly a decade of research activities, how such tools can be systematically integrated into a framework for EID preparedness. During the past three decades, canine rabies has spread to previously free areas of Southeast Asia, threatening the rabies-free status of countries such as Timor Leste, Papua New Guinea and Australia. The program of research to address rabies preparedness in the Oceanic region has included scanning and surveillance to define the emerging nature of canine rabies within the Southeast Asia region; field studies to collect information on potential reservoir species, their distribution and behaviour; participatory and sociological studies to identify priorities for disease response; and targeted risk assessment and disease modelling studies. Lessons learnt include the need to develop methods to collect data in remote regions, and the need to continuously evaluate and update requirements for preparedness in response to evolving drivers of emerging infectious disease.

scholarly journals Мансийские исследования: от истоков к современности

2020 ◽  
Vol 13 (3) ◽  
pp. 743-765
Author(s):  
Natalia A. Koshelyuk ◽  
◽  
Keyword(s):  
20Th Century ◽  
18Th Century ◽  
Field Studies ◽  
Online Research ◽  
Late 20Th Century ◽  
Research Activities ◽  
Language Research ◽  
The 19Th Century ◽  
Historical Methods ◽  
First Time

Introduction. The article reviews background studies on the Mansi language and its dialects performed by European and Russian (Soviet) linguists. Goals. The paper seeks to provide a comprehensive historical description of Mansi language research. Methods. The descriptive and comparative-historical methods have been employed thereto. Results. The work arranges the studies chronologically — from earliest research activities to contemporary ones — highlighting most essential achievements. Mansi is one of the least studied languages with earliest written accounts dating to the 16th-17th centuries. The earliest Mansi dictionaries were compiled by explorers and missionaries (I. Kuroedov, S. Cherkalov, P. S. Pallas, etc.) in the 18th century. In the 19th century, the Mansi language officially became a subject of scientific research, and expeditions by Finnish and Hungarian linguists (Antal Reguly, August Engelbrekt Ahlqvist, Bernát Munkácsi, Artturi Kannisto) proved the first field studies. In the 20th century, quite a number of European scientists have contributed to Mansi language research, namely: W. Steinitz, L. Honti, K. F. Кarjalainen, M. Bakró-Nagy, K. Rédei, M. Szilasi, and others. In Russia, the first Mansi studies were initiated by Soviet scholars in the 1930s (V. Chernetsov, A. Balandin). Studies in spoken Mansi evolved into a national Cyrillic alphabet, and for the first time ever there were published comprehensive works dealing with Mansi studies, textbooks on Mansi phonetics, morphology, and grammar. Experimental phonetic explorations emerged in the mid-to-late 20th century resulting in new Mansi dictionaries (A. Sainakhova, T. FrankKamenetskaya, E. Rombandeeva, and others). Mansi studies in the 21st century in Russia and Europe have reached a brand new level: there appeared online research laboratories and linguistic platforms which make it possible to further investigate the Mansi language and verify up-to-date materials.

The engineering significance of Pleistocene stratigraphy in the Saskatoon area, Saskatchewan, Canada

1970 ◽  
Vol 7 (2) ◽  
pp. 116-126 ◽  
Author(s):  
A. B. MacDonald ◽  
E. Karl Sauer
Keyword(s):  
Three Dimensional ◽  
Field Studies ◽  
Engineering Properties ◽  
Shear Strength Parameters ◽  
Tunnel Excavation ◽  
Glacial Sediments ◽  
Stratigraphic Analysis ◽  
Field Investigations ◽  
Stratigraphic Framework ◽  
Engineering Significance

It was recognized that repeated stages and substages of glaciation in Saskatchewan during the Pleistocene Epoch produced a series of overlapping sediments. It was shown that these sediments could be analyzed for engineering purposes within a three-dimensional stratigraphic framework. Preliminary field investigations indicated that a stratigraphic analysis could be related to construction problems found on highway embankment construction, gravel location, and tunnel excavation. Field studies established that it is practical for the field engineer to analyze and interpret the stratigraphy in the field. Furthermore, laboratory studies indicated that there were significant differences in the engineering properties of different drift-stratigraphic units. It was shown that the behavior of the till units during construction could be explained in terms of the fundamental engineering properties of soils such as shear strength parameters and compressibility. Finally, it appeared to be probable that the basic concepts developed in this study would apply to other areas covered by glacial sediments.

Review of Studies concerning Effects of Unbound Crushed Concrete Bases on PCC Pavement Drainage

1996 ◽  
Vol 1519 (1) ◽  
pp. 51-58 ◽  
Author(s):  
Mark B. Snyder ◽  
James E. Bruinsma
Keyword(s):  
Drainage System ◽  
Field Studies ◽  
Recycled Concrete ◽  
Concrete Aggregate ◽  
Drainage Systems ◽  
Concrete Aggregates ◽  
Recycled Concrete Aggregates ◽  
Crushed Concrete ◽  
Pavement Structures ◽  
Natural Aggregates

Recycled concrete aggregate (RCA) products are sometimes used as replacements for virgin aggregate products in concrete pavement structures. Recent concerns have centered on the deposit of RCA-associated fines and precipitate suspected of reducing the drainage capacity of RCA base layers and associated drainage systems. Environmental concerns have focused on the relatively high pH of the effluent produced by untreated RCA base layers. Several studies have examined these concerns and others; the results of some of these studies have not been published or publicized. The most relevant of these studies are summarized herein. These research efforts demonstrate that calcium-based compounds are present in most recycled concrete aggregates in quantities sufficient to be leached and precipitated in the presence of carbon dioxide. Precipitate potential appears to be related to the amount of freshly exposed cement paste surface. Thus, selective grading or blending with natural aggregates can reduce, but not eliminate, precipitate problems. It was also noted that insoluble, noncarbonate residue makes up a major portion of the materials found in and around pavement drainage systems. Washing the RCA products before using them in foundation layers appears to reduce the potential for accumulation of dust and other fines in the drainage system, but probably has little effect on precipitate potential. Field studies have shown that precipitate and insoluble materials can significantly reduce the permittivity of typical drainage fabrics but that attention to drainage design details can minimize the effects of these materials on pavement drainage.

scholarly journals Evaluation of the drainage system of Zagros Basin (Greater Zab River, northern Iraq) and insights into tectonic geomorphology

2020 ◽  
Vol 13 (22) ◽  
Author(s):  
Ziyad Elias ◽  
Varoujan K. Sissakian ◽  
Nadhir Al-Ansari
Keyword(s):  
Drainage System ◽  
Tectonic Activity ◽  
Mature Stage ◽  
Tectonic Geomorphology ◽  
Drainage Basins ◽  
Main Trunk ◽  
Northern Iraq ◽  
Clastic Rocks ◽  
North Iraq ◽  
Anomaly Index

AbstractGeomorphological evaluation was carried out for three drainage basins named Hareer, Dwaine, and Hijran, which are tributaries of the Greater Zab River in the northern part of Erbil Governorate, the Iraqi Kurdistan Region, north Iraq. The exposed rocks in the three basins are mainly clastic rocks (sandstone, claystone, and conglomerate, with subordinate gypsum and limestone beds). However, in the uppermost parts of the basins, thick and massive carbonate rocks are exposed. Tectonically, the three basins are located in the Low Folded and High Folded Zones, which belong to the Zagros Fold–Thrust Belt. The main aim of the current study is to deduce the tectonic activity of the area occupied by the studied three basins. We have used and interpreted Radar Topography Mission (SRTM) data to perform the geomorphological evaluation. Different geomorphological indices and forms were used to deduce the tectonic activity of the area occupied by the three basins. Accordingly, seven orders of streams were identified in the three basins. The number of the streams with low order (i.e., 1) joining with higher order (i.e., 6 and 7) is considerably higher in the three basins. The Hat values of the three basins are 12,971, 10,479, and 7014 in Hareer, Dwaine, and Hijran basins, respectively. The values of hierarchical anomaly index (Δa) of the three basins are 1.87, 1.35, and 2.37 in Hareer, Hijran, and Dwaine basins, respectively. It was observed that the shape of Hareer and Shakrook anticlines has a significant impact on the main trunk of the channel. Therefore, when an anticline and syncline are close to each other (due to thrust faulting), then the hierarchical anomaly increases because the river trunk receives a lot of first-order streams, e.g., in Dwaine and Hijran basins. The lateral growth in the eastern part of Safin anticline had caused increasing of the Δa. The increased hierarchical anomaly index is attributed to the existence of faults and lineaments, which represent weakness zones. The hypsometric curves of the three basins have a typical shape of old stage with rejuvenation in their central and terminal portions which is changed into mature stage, most probably due to the local uplift which is caused by normal, thrust, and strike–slip (oblique) faults which exist in the study area and the near surroundings. The Bs and Hat values in Hareer, Dwaine, and Hijran basins indicate that the basins exhibit low, medium, and high tectonic activity, respectively.

scholarly journals Design of Medium Depth Drainage Trench Systems for the Mitigation of Deep Landsliding

Geosciences ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 174
Author(s):  
Federica Cotecchia ◽  
Rossella Petti ◽  
Dario Milella ◽  
Piernicola Lollino
Keyword(s):  
Slip Surface ◽  
Limit Equilibrium ◽  
Drainage System ◽  
Field Studies ◽  
Stability Factor ◽  
Deep Drainage ◽  
Predisposing Factor ◽  
Mitigation Measure ◽  
Transient Seepage ◽  
The Stability

For those slopes where the piezometric regime acts as internal landslide predisposing factor, drainage may represent a more effective mitigation measure than other structural interventions. However, drainage trenches have been generally considered as mitigation measure solely for shallow landslides. More recently, instead, some authors show that the variation in piezometric conditions at large depth is not negligible when medium depth drainage trenches are involved. The paper presents the results of finite element analyses of the transient seepage induced by the installation of systems of drainage trenches of different geometric parameters, and the effect of the drainage system on the stability factor of the slip surface, through 2D limit equilibrium analyses. The pilot region is the Daunia Apennines, where field studies have led to recognize for most of the landslides a “bowl-shaped” slip surface; the results accounting for the Fontana Monte slope at Volturino (Italy), selected as prototype landslide in the assessment of the stabilization efficacy of deep drainage trench systems, is discussed in the following. The study aims at providing indications about the design of the drainage trenches to reduce the pore water pressures on a deep slip surface of such type.

scholarly journals Dynamik dichter, gleichförmiger Gebirgsfichtenwälder

2013 ◽  
Vol 164 (2) ◽  
pp. 37-46 ◽  
Author(s):  
Peter Bebi ◽  
Frank Krumm ◽  
Urs-Beat Brändli ◽  
Andreas Zingg
Keyword(s):  
Basal Area ◽  
Field Studies ◽  
National Forest Inventory ◽  
Active Management ◽  
Small Scale ◽  
Mountain Forests ◽  
Damage Potential ◽  
Research Activities ◽  
Federal Institute

Dynamics of dense, uniform spruce-dominated mountain forests Dense, uniform stands have increased in spruce-dominated mountain forests during the last century and often cause silvicultural problems. During recent years, different research activities at Swiss Federal Institute for Forest, Snow and Landscape Research (WSL) have addressed the development of such mountain forests with or without active management. For this, plots of the Swiss National Forest Inventory (NFI) between 1983/1985 and 2004/2006 have been analysed, dendroecological methods have been used to investigate competition and selfthinning processes and a reassessment of WSL long-term investigation plots has been conducted. NFI plots of stands which have already been dense during the first inventory period generally showed increasing basal area, stagnating stem numbers, strongly increasing amounts of deadwood and slightly increasing regeneration levels, both in managed and in unmanaged stands. Dendroecological field studies confirm that trees in the generally about 80 to 150 years old stands were strongly affected by competition-induced self-thinning and subsequent small-scale mortality processes few decades after stand initiation already. WSL long-term investigation plots generally confirm this dominance of relatively small-scale processes, but also show potential for silvicultural interventions, especially in early stages of self-thinning. According to the guidelines for silvicultural intervention in forests with protective functions (NAIS), an active management of later self-thinning stages with already short crowns and higher mortality should focus on stands where risks have to be considered as too high, based on hazard and damage potential and the size of the dense, uniform stands.

Glacial meltwater microbes: are there seasonal trends in exported assemblages over different catchment sizes?

2020 ◽  
Author(s):  
Kristýna Jachnická ◽  
Tyler J. Kohler ◽  
Lukáš Falteisek ◽  
Petra Vinšová ◽  
Marie Bulínová ◽  
...  
Keyword(s):  
Drainage System ◽  
Greenland Ice Sheet ◽  
Assemblage Structure ◽  
Rrna Gene ◽  
Outlet Glacier ◽  
Efficient System ◽  
Microbial Life ◽  
Sediment Bed ◽  
Catchment Size ◽  
Subglacial Drainage

<p>Glaciers and ice sheets host diverse microbial life within the hydrologically connected supraglacial, englacial, and subglacial habitats. Microbial cells are collected from the entire glacial ecosystem by seasonally-generated meltwater and exported by proglacial streams. Over the course of the melt season, a subglacial drainage system develops beneath outlet glaciers from the Greenland Ice Sheet (GrIS). This system evolves from an inefficient distributed network to a more efficient channelized pathway. The extent and interconnectivity of the subglacial drainage system with the surface and sediment bed is hypothesized to differ with catchment size.</p><p>In this study, we ask whether microbial export from GrIS outlet glacier systems depend on catchment size and whether they evolve with subglacial hydrology over time. We hypothesize that larger catchments will have proportionally greater subglacial drainage, which may be reflected in a greater proportion of subglacial microbes compared to smaller catchments, where the supraglacial inputs might have a higher influence on the exported meltwater. We also expect that changes in assemblage structure are likely to coincide with the evolution of the subglacial drainage system of larger catchments as the season progresses, with supraglacial inputs increasing in importance as the channelized efficient system fully develops. To test these hypotheses, we sampled three outlet glaciers of the GrIS with different catchment sizes (from biggest to smallest: Isunnguata Sermia, Leverett and Russell glaciers) over the 2018 summer. Meltwater samples were taken at the same time each day over a period of three weeks to catch temporal patterns of microbial assemblages. DNA was extracted from samples, and 16S rRNA gene amplicons sequenced to characterize assemblage structure.</p><p>This study will help us better understand the meltwater hydrology of the GrIS by describing patterns in its microbial export and the degree of influence from supra- and subglacial systems. In this current age of glacier recession, it is furthermore important to make these characterizations as we might not have opportunity in near future to investigate them in the same unchanged environment.</p>

Sign in / Sign up

Export Citation Format

Share Document