Fundamental processes within natural and constructed wetland ecosystems: short-term versus long-term objectives

2001 ◽  
Vol 44 (11-12) ◽  
pp. 1-8 ◽  
Author(s):  
R.G. Wetzel
Keyword(s):  
Pollution Control ◽  
Life History Strategies ◽  
Short Term ◽  
Water Losses ◽  
Wetland Ecosystems ◽  
Biological Communities ◽  
Physiological Tolerance ◽  
Species Succession ◽  
Standing Dead

Use of wetland ecosystems for water pollution control consists essentially of sustained induced disturbances as pollutants are loaded to complex biological communities. Objectives are to maximize pollutant loading, incorporation, and retention while maintaining highest levels of community metabolism and minimal alteration of community structure. Several basic processes are emphasized: (a) macrophyte productivity in relation to shoot:root ratios, and nutrient availability; (b) macrophyte life history strategies, succession, and biodiversity under constant pollutant stress; (c) importance of standing dead and particulate detritus; (d) functions and controlling mechanisms of heterotrophic and autotrophic periphyton in pollutant retention and recycling; (e) coupling of microbial metabolism to macrophyte retention of pollutants; (f) gaseous losses to the atmosphere; (g) losses of dissolved organic matter and its utilization; and (h) water losses by evapotranspiration and effects on wetland efficacy. Short-term wetland removal efficiencies are confounded by massive variations in retentive capacities diurnally, seasonally, and spatially, in exceeding physiological tolerance levels, and in species succession. Problems of channelization, altered microhydrology, and assimilation/retention are major in natural and non-engineered ecosystems. Wetlands are highly ephemeral and variable in their capabilities for sequestering and retention of nutrients and other pollutants.

Water Pollution Control in Developing Areas – Training and Education

1982 ◽  
Vol 14 (9-11) ◽  
pp. 1325-1335
Author(s):  
K Pöppinghaus
Keyword(s):  
Water Pollution ◽  
Developing Country ◽  
International Organizations ◽  
Pollution Control ◽  
Further Education ◽  
Federal Republic Of Germany ◽  
Short Term ◽  
Training And Education ◽  
Water Pollution Control

In training and further education in water pollution control areas in developing countries, the measures for substantial construction must be carried out as a long term strategy in the developing country and the measures for the elimination of acute emergencies as a short term strdzegy as well in the developing country and as in the donating countries. Programmes and solutions for the elimination of the critical stage of training and for further education are derived from and presented in an analysis of the state of training and further education. The aspects of training within the targets of Water Decade are especially discussed. The bulk of aid in training and further education made by international organizations and by the Federal Republic of Germany is illustrated. The demands on the training of engineers and the training possibilities are derived.

I. Measurements of pollution effects on Living Organisms Bioassays to determine allowable waste concentrations in the aquatic environment

1971 ◽  
Vol 177 (1048) ◽  
pp. 279-285 ◽  
Keyword(s):  
Public Health ◽  
Water Pollution ◽  
Health Service ◽  
Pollution Control ◽  
Public Health Service ◽  
Industrial Wastes ◽  
Short Term ◽  
Research Committee ◽  
Standard Methods

Various types of bioassays have been carried on in the United States for many years. the teens Shelford (1917) initiated studies to determine the attracting or repelling perties of various substances, such as gashouse wastes, for fishes. He developed cial methods and equipment for these studies. During the twenties and thirties, use of bioassays increased and considerable work was devoted to refining techhniques and checking water flow rates and the volume of water needed. However, there was great diversity in the bioassay methods used; the various workers d different species, different periods of exposure, wastes of different quality, d there was no uniformity in reporting of results. In fact, very often the methods used were not described so that the data obtained could not be compared with those of other workers. Examination of the results indicated that there was a wide inference in the reported toxicity levels for the same materials, even when tested h the same species. It was recognized in the forties that some standardization bioassay methods was needed if they were to be used to indicate the toxicity various wastes and other materials to aquatic organisms and provide comfarable data. Hart, Doudoroff & Greenbank (1945) reviewed the various bioassay methods in use and suggested approaches to their use for toxicity determinations and pointed out the need for completeness and uniformity in the reporting of ults. They also suggested an ‘application factor’ which could be applied to uts of short-term acute bioassay tests to estimate safe levels under conditions long-term exposure in the environment. Throughout the forties, the need for a standard bioassay method and uniform recording and reporting of results became re evident. This need for standardization was recognized in 1949 by the Biology Section of fie Environmental Health Center, U. S. Public Health Service, at Cincinnati, Ohio. is Center later became the Robert A. Taft Sanitary Engineering Center of the IS. Public Health Service. In 1949, a Sub-committee of the Research Committee the Water Pollution Control Federation was formed for this purpose. Dr Dou roff of the Aquatic Biology Section of the R. A. Taft Center was made Chairman, and an able committee was formed which drew up proposed standard methods f bioassays. The report of this Committee entitled ‘Bioassay methods for the evaluation of the acute toxicity of industrial wastes to fish’ was published in the Journal of sewage and industrial wastes in 1951. These methods were used routine and gradually improved upon by the Aquatic Biology Section of the Robert Taft Sanitary Engineering Center. Modifications of these suggested procedure were prepared by the Toxicity Subcommittee of the Research Committee of the Water Pollution Control Federation under the direction of the author and were published in the 11th Edition of Standard methods for the analysis of water and wastewater . These methods were used widely and were accepted as standard methods for short-term acute bioassays using fish. The need to devise method employing other organisms was recognized very early and some efforts were made in this direction. The author encouraged those working with other organisms write up their bioassay methods for consideration by the Committee for inclusio in the 13th edition. However, upon examination of several methods it was decide that they should be more thoroughly tested before being included in Standard methods . Methods for long-term, continuous renewal bioassays with fish were described and approved by the Committee and are being included in the 13t edition of Standard methods . This edition is to become available late in 1970.

scholarly journals Joint energy and water management scheme for water supply systems in Romania

2019 ◽  
Vol 85 ◽  
pp. 06008 ◽  
Author(s):  
Aida Delcea ◽  
Ioan Bitir-Istrate ◽  
Roxana Pătraşcu ◽  
Cristian Gheorghiu
Keyword(s):  
Water Supply ◽  
Energy Management ◽  
Water Supply Systems ◽  
Energy Audit ◽  
Short Term ◽  
Water Losses ◽  
Management Scheme ◽  
Energy Consuming ◽  
Supply Systems

Keeping in mind the short-term and long-term aims of cost depletion and sustainable development respectively, a joint water and energy management scheme for water supply systems that leads to reduced energy losses is proposed. For water utilities, drinkable water's treatment and pumping and wastewater treatment are the main energy-consuming processes and a proportional part of this energy is wasted with non-revenue water. In Romania, these losses can reach critical levels so highlighting them becomes a crucial aspect in assessing the system's efficiency. This paper presents a scheme that combines energy audit and water balance techniques that can become a tool for both energy auditors and managers, by allowing the quantification of embedded energy of water losses. The methodology is adapted for the conditions in Romania, where data collection and processing is mainly done manually.

scholarly journals Water baths for farmed mink: intra-individual consistency and inter-individual variation in swimming behaviour, and effects on stereotyped behaviour

2008 ◽  
Vol 17 (1) ◽  
pp. 41 ◽  
Author(s):  
J. MONONEN ◽  
M. MOHAIBES ◽  
S. SAVOLAINEN
Keyword(s):  
Stereotyped Behaviour ◽  
Swimming Behaviour ◽  
Lower Amount ◽  
Short Term ◽  
Water Losses ◽  
Video Recordings ◽  
Sampling Intervals ◽  
Instantaneous Sampling ◽  
Individual Consistency

Swimming behaviour and effects of water baths on stereotyped behaviour in farmed mink (Mustela vison) were studied in three experiments. The singly-housed mink had access from their home cages to extra cages with 20.5 litre water baths. Two short-term experiments aimed to investigate how quickly adult and juvenile mink start using and how consistently they use water baths over 10 days, and whether the extent of the use correlates between dams and their females kits. A four-month experiment was designed to compare the development of stereotyped behaviour in juvenile mink housed with and without swimming opportunity. The behavioural analyses were based on several 24-hour video recordings carried out in all three experiments. There were obvious inter-individual differences and intra-individual consistency in swimming frequency and time. Farmed mink’s motivation to swim can be assessed in short-term experiments, and measurement of water losses from the swimming baths and use of instantaneous sampling with 10 min sampling intervals provide quite reliable measures of the amount of swimming. The bath use of the juveniles correlated with that of their dams, indicating that an individual mink’s eagerness to swim may have a genetic component. The lower amount of stereotyped behaviour in mink housed with water baths indicates that long-term access to baths may alleviate frustration in singly-housed juvenile farmed mink.;

Conceptual short-term memory (CSTM) supports core claims of Christiansen and Chater

2016 ◽  
Vol 39 ◽  
Author(s):  
Mary C. Potter
Keyword(s):  
Working Memory ◽  
Rapid Serial Visual Presentation ◽  
Language Comprehension ◽  
Short Term Memory ◽  
Visual Presentation ◽  
Long Term Memory ◽  
Short Term ◽  
Term Memory ◽  
Use Of Knowledge

AbstractRapid serial visual presentation (RSVP) of words or pictured scenes provides evidence for a large-capacity conceptual short-term memory (CSTM) that momentarily provides rich associated material from long-term memory, permitting rapid chunking (Potter 1993; 2009; 2012). In perception of scenes as well as language comprehension, we make use of knowledge that briefly exceeds the supposed limits of working memory.

Ultrastructural investigations of MDL 19,660-induced effects on the canine platelet and megakaryocyte

1990 ◽  
Vol 48 (3) ◽  
pp. 374-375
Author(s):  
D.E. Loudy ◽  
J. Sprinkle-Cavallo ◽  
J.T. Yarrington ◽  
F.Y. Thompson ◽  
J.P. Gibson
Keyword(s):  
Antidepressant Drug ◽  
Beagle Dogs ◽  
Long Term Effects ◽  
Short Term ◽  
Platelet Counts ◽  
Toxicological Studies ◽  
Induced Aggregation ◽  
Internal Architecture

Previous short term toxicological studies of one to two weeks duration have demonstrated that MDL 19,660 (5-(4-chlorophenyl)-2,4-dihydro-2,4-dimethyl-3Hl, 2,4-triazole-3-thione), an antidepressant drug, causes a dose-related thrombocytopenia in dogs. Platelet counts started to decline after two days of dosing with 30 mg/kg/day and continued to decrease to their lowest levels by 5-7 days. The loss in platelets was primarily of the small discoid subpopulation. In vitro studies have also indicated that MDL 19,660: does not spontaneously aggregate canine platelets and has moderate antiaggregating properties by inhibiting ADP-induced aggregation. The objectives of the present investigation of MDL 19,660 were to evaluate ultrastructurally long term effects on platelet internal architecture and changes in subpopulations of platelets and megakaryocytes.Nine male and nine female beagle dogs were divided equally into three groups and were administered orally 0, 15, or 30 mg/kg/day of MDL 19,660 for three months. Compared to a control platelet range of 353,000- 452,000/μl, a doserelated thrombocytopenia reached a maximum severity of an average of 135,000/μl for the 15 mg/kg/day dogs after two weeks and 81,000/μl for the 30 mg/kg/day dogs after one week.

Comparison of Auditory, Language, Memory, and Attention Abilities in Children With and Without Listening Difficulties

2020 ◽  
Vol 29 (4) ◽  
pp. 710-727
Author(s):  
Beula M. Magimairaj ◽  
Naveen K. Nagaraj ◽  
Alexander V. Sergeev ◽  
Natalie J. Benafield
Keyword(s):  
Auditory Processing ◽  
Short Term Memory ◽  
Group Differences ◽  
Long Term Memory ◽  
Short Term ◽  
Significant Group ◽  
Term Memory ◽  
Memory And Attention ◽  
Speed And Accuracy

Objectives School-age children with and without parent-reported listening difficulties (LiD) were compared on auditory processing, language, memory, and attention abilities. The objective was to extend what is known so far in the literature about children with LiD by using multiple measures and selective novel measures across the above areas. Design Twenty-six children who were reported by their parents as having LiD and 26 age-matched typically developing children completed clinical tests of auditory processing and multiple measures of language, attention, and memory. All children had normal-range pure-tone hearing thresholds bilaterally. Group differences were examined. Results In addition to significantly poorer speech-perception-in-noise scores, children with LiD had reduced speed and accuracy of word retrieval from long-term memory, poorer short-term memory, sentence recall, and inferencing ability. Statistically significant group differences were of moderate effect size; however, standard test scores of children with LiD were not clinically poor. No statistically significant group differences were observed in attention, working memory capacity, vocabulary, and nonverbal IQ. Conclusions Mild signal-to-noise ratio loss, as reflected by the group mean of children with LiD, supported the children's functional listening problems. In addition, children's relative weakness in select areas of language performance, short-term memory, and long-term memory lexical retrieval speed and accuracy added to previous research on evidence-based areas that need to be evaluated in children with LiD who almost always have heterogenous profiles. Importantly, the functional difficulties faced by children with LiD in relation to their test results indicated, to some extent, that commonly used assessments may not be adequately capturing the children's listening challenges. Supplemental Material https://doi.org/10.23641/asha.12808607

Abstract #283 Diabetes Increases Short-Term but not Long-Term Risk of Fracture: A Community-Based Study

2019 ◽  
Vol 25 ◽  
pp. 114
Author(s):  
Alyssa Dufour ◽  
Setareh Williams ◽  
Richard Weiss ◽  
Elizabeth Samelson
Keyword(s):  
Short Term ◽  
Community Based ◽  
Risk Of Fracture
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