bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ecology and the Zuiderzeeproject
Authors: de Jong J , Roelofs J H 
Published: May 2018

The former Zuiderzee, a large estuarne area over 500,000 ha located in the northwestern part of the Netherlands has undergone great changes due to the execution of the Zuiderzeeproject.
Within the framework of this project 375.000 ha of the area has been dammed and excluded from the influence of the sea. The waters in the area were turned into stagnant, eutrophic freshwaters by using the water from the river IJssel. In the dammed off region also four polders, having a total area of 165,000 ha have been reclaimed. A fifth polder of 41,000 ha is planned, but not yet decided upon.
The execution of this project was started in 1919 and is still not yet finished.
In the beginning of the execution of the project, due to the social and economic conditions of that time, only limited attention has been paid to ecological expects of the project during planning, execution and initial management. However the ecological changes that would occur were regarded to be very important from a scientific point if view. As a result both the original situation and the changes in the aquatic ecosystem have been monitored. Also transient high ecological values of the new polders have been well documented by the scientists. As a result when social and economic conditions changed after the second world war and especially in the period after about 1965 a sound basis of biological and ecological knowledge was present and incorporated in the state authorities invloved to enable the additions of ecological considerations into the development of both polders and lakes.
Due to the flexibility of the Zuiderzee project where the project is excecuted polder after polder in the two polders that have been made after the second world war large areas of forest and nature reserves have been realized next to other means of land use such as agriculture, infrastructure, recreation and urbanization.
By this way changing views of society reflect upon the way of development and management of both land and lakes.
Nowadays both lakes and polders provide on a international level high ecological values, especially for birds, in spite of drastic ecological changes.
A careful planning, excaition and management by state organizations, assisted by continuous research, prove to be essential factors to realize these results.
The Environmental Effects of Flood Control in the Yare Basin
Authors: Wakeling H L 
Published: May 2018

The paper reviews various methods of flood control in the lower Yare Basin which has been subject to serious flooding caused by storm surges in the North Sea and by fluvial floods. This area is known as the Broads and is an area of scenic beauty, includes many sites of scientific interest and is a popular tourist area.
The effects of the different flood control options on the environment are discussed. The primary economic justification for flood prevention was found to arise from the conversion of poor quality marsh grazing land to arable or improved pasture once the risk of saline flooding was removed. The consequences of this change in land use on the flora and fauna have aroused much concern among environmentalists.
Past and Pending Decisions Controlling San Francisco Bay and Delta
Authors: Davoren W T , Ayres J E 
Published: May 2018

Over the past 130 years, the largest inland estuary of America's west coast, the San Francisco Bay and Delta,1 has been altered greatly by land and water development. To the detriment of estuarine processes and indicator species, upstream impoundments, diversions and pumped exports from the Delta have reduced river flows by 50 percent or more. Long-term effects of the upstream impoundments and removals are just beginning to be understood. Additional storage and diversion units are planned. The responsibility for repelling salinity intrusion from the Bay to the Delta's waters is not clearly defined. Additionally, drainage projects are underway to transport land-derived salts from inland irrigated areas for discharge into the Bay's headwaters. Also, the threat of levee collapse in the Delta from erosion and subsidence advances yearly. Navigation, agriculture, recreation and fish/wildlife needs further complicate land and water management challenges in the Delta. This paper appraises the present realities produced by past projects and policies.
1Delta is used throughout as a California place name that applies to the combined areas of the Sacramento and San Joaquin River deltas (Fig. 2). The Bay begins at Chipps Island, just below the confluence of the two rivers, and extends to Golden Gate on the west and San Jose on the south (Fig. 1).
Settling Properties of Activated Sludge Related to Floc Structure
Authors: Eriksson L , Härdin A.-M 
Published: May 2018

When characterizing sludge settling by means of sludge volume index and stirred sludge volume index it has been found that the former is normally higher, but that the difference varies greatly for different sludges. It was found to depend on difference in shape of the flocs. Spherical flocs give small differences and elongated flocs give large ones. Although both indices were positively correlated to the total length of filamentous organisms the differences were not.
A general floc model is proposed on the basis of these findings together with colloid chemical considerations and measurements of floc strength, filtration resistance and amount of extracellular polymers. According to this model young flocs are of the elongated type, while flocs from a stable system are round. Sludge bulking is a consequence of stiff noncompressible flocs which may be due to high amounts of dissolved polymers, but most likely to filamentous organisms fixed in a network by binding polymers within the flocs. The amount of filaments inside the flocs is probably proportional to the amount outside which for that reason is correlated to the settling indices.
A Combination of the Activated Sludge Process with Fixed Film Biomass to Increase the Capacity of Waste Water Treatment Plants
Authors: Hegemann W 
Published: May 2018

The volume of the activated sludge aeration tank is influenced by f/m ratio and attainable biomass concentration. Increase of biomass results in smaller tank volume. In case of overloaded plants restoration may be achieved by increase of biomass instead of construction of further tank volume. Pieces of porous plastic media filled into ordinary compressed air aeration tanks may serve as fixed film biomass support. By this method biomass concentration in the tank may be increased to two or three times normal values. At the same time the sludge volume index of the activated sludge flocs still present in the aeration tank is improved. Better sedimentation and thickening of the activated sludge occurs because smaller quantities of flocs are passed to the final clarifiers.
Results of tests with different types of waste water in semi-technical scale pilot plants as well as in existing plants of different sizes are presented.
Forest Industry Anaerobic Wastewater Treatment and its Future Development
Authors: Orivuori Juhani 
Published: May 2018

Very few methods have been developed with such speed as anaerobic wastewater treatment. Universities, Government agencies, private enterprise and scientists all over the world are using millions of dollars in studies, pilot and full scale experiments trying to find the most practical anaerobic treatment systems for various wastewaters. The follow-up alone of all the information published in this field would require an institute of its own. Commercial interests are driving private enterprise to fast development of full scale treatment plants.
In this paper the reasons for this interest in anaerobic treatment are focused on in the light of the recent developments in knowledge of the quality and quantity of forest industry wastewaters. Future wastewater characteristics and the possibility of anaerobic treatment to meet future demands are discussed. The need for co-operation between forest industry process engineers and wastewater treatment specialists is emphasized in order to optimize internal and external pollution control methods.
Sludge Stabilisation and Disinfection by Means of Autothermal Aerobic Digestion with Oxygen
Authors: Trim B. C. , McGlashan J. E. 
Published: May 2018

Research at pilot-scale was undertaken into autothermal aerobic digestion of sludge using oxygen to demonstrate that sufficiently high temperatures can be achieved to ensure the degree of disinfection that would satisfy the health authorities. The ova of the helminth Ascaris lumbricoides were used in the disinfection studies and the dissolved oxygen level in the sludge was used as a means of controlling oxygen consumption.
The results achieved indicate that the system very rapidly attained a stable temperature which could be easily maintained and which effectively ensured disinfection of the sludge at the 2 and 4 day retention periods tested, that the treated sludge readily ferments anaerobically, that the sludge will not readily settle and is very difficult to dewater.
Sunlight Photooxidation of Organic Pollutants in Wastewater
Authors: Acher A. J. 
Published: May 2018

The material presented represents results of a research on a new method for using solar energy for municipal and industrial wastewater treatment. This research seeks to develop economical methods of disinfection and detoxification of wastewaters which would result in the reuse of effluents for crop irrigation.
Aerated effluents containing dye-sensitizers were exposed to solar irradiation for various periods of time. The influence of the solar energy, absorbed by these sensitizers in the visible range, on the organic matter and anionic surfactants in secondary effluents was checked by determining the COD and MBAS values of treated wastewater.
The disinfection potential of this method was followed by bacteriological analyses of running water or secondary effluents, previously contaminated or enriched, respectively, with laboratory cultures of E. coli, bacteriophages (coliphage X and F2) and polio virus (type L-Sc 1).
The influence of this photooxidative method was also studied in eutrophic algae present in the Lake of Galilee. It was found that the conditions under which disinfection proceeds also support algicidal processes, causing lethal damage to algal cultures.
Further investigations on stable pesticides (uracil, s-triazine and anilide derivatives) in surface water or industrial wastewater showed that such a method can also be used for detoxifying pesticides in these waters.
Synthesis Modeling of Municipal Wastewater Treatment Systems
Authors: Câmara A. S. , Randall C. W. , Frair L. C. 
Published: May 2018

The synthesis of wastewater treatment systems refers to the specification of both a system structure–the choice and arrangement of unit processes and operations–and the design of the individual units within that structure so that a set of economic and environmental objectives is fulfilled. This paper shows that one can not yet develop optimal synthesis models due to limitations on cost and engineering data used as input in those models.
It is illustrated however that a rational synthesis modeling effort offers two important contributions: the development of an improved although still sub-optimal version of a wastewater treatment synthesis model; and the systematic identification of research areas to be followed if one wants to overcome the limitations above mentioned and thus enable the development of a model to guide a truly optimal design of wastewater treatment systems.
Stabilization of Organic Carbon and Nitrogen in Consolidating Benthal Deposits
Authors: Bryant C. W. , Rich L. G. 
Published: May 2018

The objective of this research was to develop and validate a predictive model of the benthal stabilization of organic carbon and nitrogen in deposits of waste activated sludge solids formed at the bottom of an aerated water column, under conditions of continual deposition. A benthal model was developed from a one-dimensional, generalized transport equation and a set of first-order biological reactions. For model verification, depth profiles of the major interstitial carbon and nitrogen components were measured from a set of deposits formed in the laboratory at 20°C and a controlled loading rate.
The observed sequence of volatile acid utilization in each benthal deposit was that which would be predicted by the Gibbs free energies of the individual degradation reactions and would be controlled by the reduction in interstitial hydrogen partial pressure with time. Biodegradable solids were solubilized rapidly during the first three weeks of benthal retention, but subsequent solubilization occurred much more slowly.
The benthal simulation effectively predicted the dynamics of consolidating, organic deposits. Simulation of organic loading rates up to 250 g BVSS/(m2 day) indicated that the stabilization capacity of benthal deposits was far above the range of organic loading rates currently used in lagoon design.
Modelling of the Coagulation–Adsorption Process in Treatment Systems
Authors: Dziubek Andrzej M. , Kowal Apolinary L. 
Published: May 2018

Removal of organics in water or wastewater treatment systems is often described mathematically in the form of Langmuir and Freundlich adsorption isotherms. Using these equations, it is convenient to model, e.g., the removal of organic matter in the adsorption process on an activated carbon bed. In chemical treatment processes, organic substances are frequently removed from the water or wastewater under treatment via an adsorption on the precipitation products.
In this paper presented is a generalized model of the equation of a multilayer adsorption isotherm, which describes TOC removal from a solution during chemical treatment in an alkaline medium. The model also includes the nonremovable concentration of organics.
Modeling Water Quality and the Effects of Agricultural Best Management Practices in the Iowa River Basin
Authors: Bicknell B. R. , Donigian Anthony S. , Barnwell T. A. 
Published: May 2018

This paper describes a demonstration application of comprehensive hydrology and water quality modeling on a large river basin to evaluate the effects of agricultural nonpoint pollution and proposed best management practices (BMP). The model application combines detailed simulation of agricultural runoff and soil processes, including calculation of surface and subsurface pollutant transport to receiving water, with subsequent simulation of instream transport and transformation. The result is a comprehensive simulation of river basin water quality.
The investigation of the Iowa River Basin described in this paper was part of a large study which included application and evaluation of the Hydrological Simulation Program - FORTRAN (HSPF) to both the data-intensive Four Mile Creek watershed and the Iowa River above Coralville Reservoir. In this study, the methodology developed on Four Mile Creek was extrapolated to the Iowa River Basin to demonstrate its applicability and functionality on a large river basin. Many model parameter values from Four Mile Creek were applied directly to the study area without adjustment while other parameters were modified based on available information and calibration. This study allowed the exploration of problems associated with modeling hydrology, sediment, and chemical fate and transport in a large river basin with varying meteorologic conditions, soils, and agricultural practices.
Two Options for Treatment of Acidic Organic Industrial Wastes
Authors: Millot N. , Dalga N. , Foussard N. 
Published: May 2018

The treatment of acidic, organic, industrial wastes poses many problems. These wastes are characterized by a high organic concentration and pH values approaching zero. The classic treatment processes (incineration, physicochemical treatment, solidification) are plagued by problems with corrosion, by-products formation and ultimate disposal.
This paper proposes two new processes for treating these wastes. The first technique is a pressurized oxidation process at high temperature. Results show total organic carbon (TOC) removal above 96%.
The second proposed technique is an improved solidification which incorporates an adsorbent into the solid to immobilize the organic content. A very thick sludge (solids about 60%) is obtained which dries very quickly. Tests on the solids indicate that any leachate formed will be much lower in strength than leachate from the classic solidification process.
Landfill disposal of the solidified waste is possible under proper conditions.
Coastal Ecology and the Arctic Oil Industry: Some Elements for Future Oil-Spill Contingency Planning
Authors: Sendstäd E. 
Published: May 2018

The ecological vulnerability of shorelines to oil contamination varies and their self-cleaning ability may be extensive. The ice may restrict the spread of oil. In the biologically active season, oil contamination in this environment will affect an important foodchain. Both the ice and shoreline environments have elements which positively and negatively influence the planning of countermeasures for oil-spills.
Offshore oil production in the Arctic is expected to be dependent on enhanced oil recovery (“EOR”). Thus any future environmental impact analyses of the offshore petroleum industry should include this aspect.
It is important to analyse the functional aspects of arctic ecology to single out the most vulnerable situations. An oil-spill clean-up plan should avoid vulnerable areas and seasons of the year, and use effective countermeasures in the less sensitive situations.
Reduction of Pulp and Paper Industry Effluent Loading
Authors: Luonsi A. , Vuoriranta P. , Hynninen P. 
Published: May 2018

The pulp and paper industry consumes large volumes of water i.e. 10-300 m3/t of product. The most important measure in reducing the pollution charge is a reduction in water consumption. Thereafter, efficient and more easily controllable methods can be used for the treatment of lower volume, more concentrated and warmer wastewaters. Application of medium consistency techniques in production, water recirculation, and more efficient use of wood are pushing development in this direction. It is clear however, that these development trends will undergo certain practical limitations governed by the actual production process.
The trends in production favour the utilization of anaerobic techniques in wastewater treatment. Both the purification efficiency and the economy of the treatment system can be improved as seen from the examples in this paper. However, the conventional aerobic treatment is under continuous development and it will be applied as a completing stage of anaerobic treatment. Modifications of the activated sludge process can be applied especially for rather dilute composite pulp mill effluents as presented in this paper.
Tanneries: A Short Survey of the Methods Applied for Wastewater Treatment
Authors: Tsotsos D. 
Published: May 2018

A short description of the tannery production process is given, mentioning the main points related to an effluent discharge. Qualitative and quantitative data are presented and several methods used for wastewater treatment are also reviewed. It is stated that biological systems (activated sludge) cannot be operated in the same way as for municipal effluents, since tne main pollutants (Cr - salts, sulfides) negatively affect the action of microorganisms. Therefore, a pretreatment step is required prior to the effluent discharge into a municipal treatment plant.
Another problem is the treatment and disposal of the precipitated sludge. Several already applied methods trying to eliminate the problem are discussed.
All represented data are taken from research studies published in international 1iterature.
The Pollution of the Beaches of Alexandria due to the Discharge of Sewage: A Case Study
Authors: El Sharkawi F. 
Published: May 2018

Alexandria is the main summer resort of Egypt. The population of the city is about 3 million and in summer it receives about half a million tourists who come to its beaches for recreation. Part of the city sewage is discharged into the sea through some outfalls along the coast. A coastal line of about 20 kms in length was monitored in order to study the pollution of the recreational waters. Also, a retrospective epidemiological study was carried out to find if there was a relation between the state of pollution and the occurrence of typhoid among bathers. The results of this study showed that there was a significant risk of contracting typhoid from bathing in the heavily polluted water and the most affected was the young age group.
Therefore, it was recommended that the minor outfalls should be closed immediately to protect the public health, and a long outfall as recommended by the Master plan should be constructed as quickly as possible.
Eutrophication of Coastal Waters – Gulf of Trieste
Authors: Olivotti R. , Faganeli J. , Malej A. 
Published: May 2018

In this paper, ‘eutrophication' is defined as ‘undesirable degradation of the aquatic environment (caused by an excessive algal biomass) resulting in a deterioration of water quality which interferes with most of the beneficial uses of water; it is causing, in many cases, significant economic losses' (OECD, 1982). In other words, eutrophication is seen as a form of pollution.
To achieve an evaluation of the relevance of this problem in the Gulf of Trieste, the main results of extensive chemical and biological monitoring carried out both by the Yugoslav and Italian sides in the last decade are briefly reviewed. The large amount of data on dissolved oxygen, transparency, chlorophyll, and on the obnoxious occurrence of coloured waters, indicate that the great majority of the Gulf waters are not affected by eutrophication (according the above definition); rather, the major part of the eastern (Yugoslav) waters appears to be essentially oligotrophic. Strong eutrophication, however, sometimes affects the inner part of semi-enclosed bays where large quantities of organic matter and nutrients are discharged. Such areas, such as the inner part of the Bay of Muggia, are severely polluted in many respects. A better form of treatment and disposal of sewage from Trieste (which is severely polluting the Bay of Muggia) would be advisable, and would also achieve amelioration of the trophic levels in areas laying outside the bay.
The examination of numerous data concerning nutrient concentrations leads to some conclusions of significance, essentially consistent with the conclusions given above. The ƩNinorg./PO43− atomic ratio often exceeds 20. More difficult, and somewhat debatable, appears to be the assessment of the more subtle impacts of nutrients on the marine environment, given the uncertainties about the ‘natural' and/or ‘optimal' conditions to be assumed, the large variations of the ‘natural' conditions themselves, and the reaction of the environment to superimposed natural and anthropogenic impacts. This paper can be viewed as a preliminary to a more extensive review concerning, in addition, the more subtle effects induced by ‘non optimal' trophic conditions.