Çevre Bilimleri Enstitüsü

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Wastewater treatment by land disposal on sandy grounds
(Thesis (M.S.) - Bogazici University. Institute for Graduate Studies in Science and Engineering, 1984., 1984.) Baysal, Ayşegül.; Curi, Kriton,
Wastewater disposal on land can be considered as "appropriate" wastewater treatment technology for many less developed and developing countries. The main advantages of .this technique are the low initial and maintenance costs involved, the effective reduction of the organic load as well as the removal of bacteriological pollution, reuse of nutrients such as nitrogen and phosphorus present in the was,tewater through retention by soil and the increase of the productivity of the soil. Treatment of wastewater by land application has not been practised so far in Turkey. The present study was conducted to investigate the applicability of this method in our country and to predict the results. For this purpose, a 25 meter long channel was constructed and after it was filled with sand, domestic wastewater was applied. The variation of the wastewater and soil characteristics with time and distance were investigated through out the application period. Removal efficiencies obtained are given below: Chemical oxygen demand (COD) 74-84 % - Nitrogen (N) 65-75 Z - Phosphorus (P) 73-92 % - Turbidity 75-80 Z - Total coliform 77.5-82.5 % These results are in full agreement with the results of similar studies conducted elsewhere. The conclusion of the present study is that land disposal on sandy grounds is a method which can be used effectively in many parts of Turkey.
Scale effect of modelling on biogas generation
(Thesis (M.S.) - Bogazici University. Institute for Graduate Studies in Science and Engineering, 1984., 1984.) Çukurova, Recep.; Curi, Kriton,
Anaerobic decomposition of manure i s an outstanding alternative energy source, appropriate for most developing countries. Several studies related to this subject were conducted so far, however, the effect of the size of the inodel on the efficiency obtained was not investigated. The main purpose of the present study was t o investigate, the scale effect on the perfomance of an anaerobic digestion. To achieve this three digesters , each of different size and voluue, were installed and operated under ambient conditions. The results obtained have shown that: 1. The size of the model has as light effect on the efficiency of anaerobic digestion, better performance being obtained in larger model. 2. Any digester can be operated under ambient conditions if proper insulating precautions are taken. 3. Mixing has a positive effect on biogas generation. 4. The positive effect of yeast on anaerobic decomposition is verified .
Efficiency of wastewater treatment by land disposal and its effects on crop productivity
(Thesis (M.S.) - Bogazici University. Institute for Graduate Studies in Science and Engineering, 1985., 1985.) Üstün, Beyza.; Curi, Kriton,
Land application of wastewater is one of the oldest methods used for treatment and disposal of wastes.The main advantages of this technique are the low initial and maintenance costs involved,high Nutrieht recyle capacity, and the increase of crop growth. Because of these factors it is believed that land disposal is an advantageous thechnique for deyelooing countries and is strongly recommended for the rural areas of Turkey. in 1984, a 25 meters long channel was constructed by A-Bavsal in Boğaziçi University's Garden.These Channels were filled with sand and gravel domestic wastewater was applied. The variation of wastewater characteristics with timerdistance and effective size of media were investijated through out the anplication period in 1985. Removal efficiencies obtained are given below: Chemical Oxvqen Demand(C0D) 76% in the Sand bed for 35days - 60% in the Gravel bed for 35days -- Nitrogen (N) 70% in the Sand bed for 35 days - 57% in the Gravel bed for 35days -- Phosnhorus (P) 77% in the Sand bed for 35 days - 64% in the Gravel bed for 35days. The study of crop productivity has been performed at Faculty of Forest of Istanbul University. Its aim was to examine the crop productivity of the media through which wastewater has been disnosed.The best result was obtain from a mixture containing 80% of the media and 20% of soil.
Heavy metal taxicity on blue-green alga
(Thesis (M.S.)- Bogazici University. Institute of Environmental Sciences, 1986., 1986.) Berk, Hüma.; İnel, Yüksel.
In this study, the growth response of Anabaena flos-aquae, which is a filamentous, heterocystous blue-green alga, towards heavy metals i s described. The experiments were long term, batch type experiments, and algae were incubated in media containing Hg(I1) as mercuric chloride (HgC12) ,Cd(II) as cadmium chloride (CdC12), Se(1V) as sodium seleni te (Na2Se03), Ni (11) as nickel chloride (NiCI2.6H20) ,Cr(VI) as potassium chromate(K2Cr04) and As(V) as sodium arsenate (Na2HAs04). 7H20) in solution. Growth i s measured spectrophotometrical ly and optical density is used in the expression of results. In all cases, metals were found to be inhibitory on the growth, the degree of inhibition depending upon the type of the metal ion and the concentration in the medium. I t was found that in media contaminated with 10,20 ppm selenium and 0.2 ppm nickel, the growth of cells failed complelety.
A numerical model for the Marmara sea
(Thesis (M.S.)- Bogazici University. Institute of Environmental Sciences, 1987., 1987.) Albek, Erdem Ahmet.; İnel, Yüksel.
In this study, a numerical model has been developed to predict currents and water levels prevailing in the Marmara Sea. The model is a depth averaged two-layer transient model to adequately simulate stratified flow conditions in the sea. The nonlinear partial differential equations of the model have been solved by using an explicit finite difference scheme and employing a local integral method to reduce truncation and round-off errors and to improve accuracy. Special emphasis has been laid on the prediction of currents and water levels under strong winds.
Valance molecular connectivity model in the prediction of compartmental distribution of selected aromatic pollutants
(Thesis (Ph.D.)- Bogazici University. Institute of Environmental Sciences, 1987., 1987.) Menemenli, G. Feryal.; İnel, Yüksel.
The main purpose of this work is to develop a mathematical model based on the Valance Molecular Connectivity theory which is initiated as an extension of graph theory having its roots especially in structure-activity studies concerning drug-design and toxicity prediction in pharmaceutical chemistry, to evaluate the compartmental distribution of various aromatic pollutants in the environment. During the last decade concerns have been expressed as to the "best way" to assess the potential hazards posed by exposure to chemical substances. In response to these concerns, the chemical group of OECD initiated a hazard assessment project to examine the available methods for hazard assessment of chemicals. The main purpose being to determine how information on theultimate fate and effects of a chemical can be derived from the set of premarket data, the group accepted four models for the estimation of exposure potentials of chemicals within environmental compartments of major concern. Ail of the four models accepted by OECD chemical group was based on the concept of fugacity and essentially needed the following data e molecular weight e water solubility e vapor pressure e soil sorption constant e octanol-water partition coefficient However, the availability and precission of the set of data proposed, especially for chemicals which have rather large and complicated structures was a drawback of these models. Hence, a reasonable model to evaluate this distribution quantitatively without needing such hard-to-gather data would have been a remarkable advance in prediction of environmental hazards that are going to be caused by unknown chemicals irrespective of size and conformation. In this work a new mathematical model (VMCI) based only on the topological characteristics of molecules is deveioped in order to evaluate the distribution of chemicals within various compartments of the environment such as air, soil, water, biota, suspended solids and sediment. The Valance Molecular Connectivity Index, which is the basis of this new model is known to correlate significantly with a number of structure dependent physicochemical properties, and by this wock lt has now been shown to have a high degree of correlation also with water solubilities, vapor pressures and partition coefficients hence wlth the partitioning properties of molecules. As a result, by comparing the two completely different methods of evaluation (VMCI and Level I Fugacity Models) this work proved that it is possible to predict the compartmental distribution of any aromatic compound quantitatively within a high accuracy just by considering the molecular geometry. The superiority of this model compared to fugacity dependent models accepted by OECD lies in the fact that it does not require the physical data such as solubility, vapor pressure or partition coefficient. Relevantly another superiority comes out to be the ability to stay as accurate when even very complicated molecules are investigated while for fugacity dependent models accuracy diminishes due the difficulties in obtaining the experimental data.
Environmental distribution of polychlorinated biphenyls by topology based characteristic root index
(Thesis (Ph.D.)- Bogazici University. Institute of Environmental Sciences, 1990., 1990.) Saçan, Melek Türker.; İnel, Yüksel.
Relationships between a newly developed index -which is based on topological characteristics ofthe molecules and called the Characteristic Root (CR) index- and the environmentally relevant physicochemical properties of the Polychlorinated Biphenyls, namely, aqueous solubility, vapour pressure, Henry's Law Corastants, and octanol-water partition coefficient are discussed. Correlations performed on the congeners clearly demonstrate that the CR index model accurately predicts the physicochelnicaiproperties of PCBs. Highcorrelationcoefficient (r = 0.998) was calculated for the linear one-parameter correlation between the CR index and molecular total surface area. So, the CR index was used in the prediction of pro2erties dependent on tetal surface area. The quality and reliability of the correlations are show to be high enough for environmental applications. Reported experimental physicochemical data of PCBs are tabulated, Recomended values are given for 58 of the 209 congeners, With the available data, it is possible to estimate what percentage of the chemical will be located in the soil, bottom sediments, water and air. The predicted and experimental physicochemical properties of PCBs were used to predict the environmental compartmentalization of these compounds in an evaluative environment using the fugacity approach.
The predicted environmental distribution of selected flame retardant chemicals
(Thesis (M.S.) - Bogazici University. Institute for Graduate Studies in Science and Engineering, 1991., 1991.) Baysan, Semra.; İnel, Yüksel.
The aim of this study is to calculate environmental equilibrium distributions for selected Flame Retardant Chemicals and thus to indicate where each of them goes and what relative concentrations they adopt in the enviromental compartments. In this study, Mackay's Level I Fugacity Model, based on fugacity that characterizes the escaping tendency from a phase, is used for calculations. The fugacity calculations are applied to an evaluate environment a "unit world" consisting of compartments of homogeneous air, soil, water, biota, suspended solids and sediment. Each compartment is assigned a reasonable volume and properties and the equilibrium distributions of those chemicals are calculated using fugacity capacities, that are calculated from physical and chemical data partition coefficients. When the results are designed to yield priorities for each compartment, it is found that Halognated Flame Retardant Chemicals for the air compartment, Phosphorus Flame Retardant Chemicals in the Sediment and Soil compartments are priorities.
Evaluation of the Eutrophication process in lake İznik
(Thesis (M.S.)- Bogazici University. Institute for Graduate Studies in Science and Engineering, 1993., 1993.) Zakrı, Fawaz.; Akkoyunlu, Atilla.
Lake Iznik is located in the southern east part of Marmara region within the province of Bursa . Its water is of a big importance to the region with a Mediterranean climate, and an annual rainfall ranging between 500 - 750 rom, falling mainly in the period from October to March . This water is used in dry season for irrigation . In this thesis, a physical study of the region is conducted . The physical , chemical and biological parameters were examined at several sites in order to determine the eutrophication state and a suitable model was applied to represent the lake . Lake Iznik was found to be very near to the eutrophic state and the limiting nutrient in the lake was found to be the phosphorus element .
Waste biomass in Turkey and solar drying as a new alternative for its utilization as feed
(Thesis (Ph.D.) - Bogazici University. Institute Environmental Sciences, 1993., 1993.) Tosun, Ayşe.; Saygın, Ömer.
Sources of waste biomass in Turkey were classified in this study. The amounts belonging to the items of the classification were estimated. The current use of these wastes were discussed and it was suggested that the best way to recycle nutritious wastes was using them as feed. Since some of these wastes are high in moisture, it is essential to protect them against bacterial spoilage by drying. Drying, on the other hand, is an energy intensive process. The economical feasibility as well as the ecological benefit of drying wastes by burning fuels is questionable. An economical solution at least for countries with abundant solar insolation would be the use of solar energy for drying. Various methods of solar drying of food wastes were examined. Open air as well as forced air drying gave bacteriologically inadequate products. Therefore, solar boiler dryers, working at 105°C, were constructed. To prevent the observed temperatures higher than 105°C at the later stages, drying was conducted in two stages. While sterilization and removal of most of the water were achieved by boiling in the solar boiler dryer at the first day, open air drying at the second day allowed to obtain a light brown colored product with trace amounts of bacteria and mold. The energy efficiency for vaporization was 85%. Heat losses of the whole dryer due to reflection, convection, and radiation were calculated to be 13%, 7%, and 20%, respectively. Suitability of the material obtained, as animal feed, was tested on broiler chickens. The results indicated that soybean meal protein in broiler diets, can be replaced by the protein of this product up to 40% without any reduction of the weight gain of the birds.|Keywords: Biomass, Food Wastes, Recycling, Solar Drying of Wastes, Feed from Wastes
Investigation of nitrification characteristics of a nitrogenous industrial wastewater
(Thesis (M.S.) - Bogazici University. Institute of Environmental Sciences, 1994., 1994.) Gökçin, Pınar.; Çeçen, Ferhan.
Treatment of wastewaters containing very high amounts of nitrogen is a problem for industries like the fertilizer industry. Up to date methods like air stripping or ion exchange can also be used in removal of nitrogen but they have certain disadvantages. The main purpose of this thesis was to present another known process used in nitrogen removal. The general concern of the study is to determine if nitrification process could tolerate industrial wastewaters containing high concentrations of nitrogen. In the beginning of the experimental part of the study, sludge previously acclimated to nitrification was introduced to increasing concentrations of ammonium nitrogen. In the second part of the study, wastewater from a fertilizer industry was used in order to detect the removal capacity of the system. Throughout the study effects of pH on the system and the system's tolerance was observed. Data obtained during the study proved that nitrification is a process that behaves according to the zero order kinetics. Finally, the results indicated that a nitrification process can surmount very high amounts of nitrogen if the environmental conditions are idealized.
The characteristics and reuse of Golden Horn surface sediments
(Thesis (M.S.) - Bogazici University. Institute of Environmental Sciences, 1994., 1994.) Aydın, Zehra Semra.; Karpuzcu, Mehmet.
In this study the characteristics and reuse of Golden Horn surface sediment were investigated. 40 per cent of the water content of the sediment is free and immobilised water, and the remaining 60 per cent is bound water content. In accordance with these results, the high specific resistance value of the sediment indicates its poor dewaterability characteristics. The leachate of the samples does not contain the toxic heavy metals even if the deposits get into contact with acid rain of pH 4. The sediment has strong Cu and Pb adsorption properties. Considering the metal content of the sediment, it is obvious that the sediment is not saturated with these metals. Another important characteristic of the samples IS their high buffering capacity. The reuse of the dried sediment as a clay mixture III brick manufacturing seems possible.|Keywords: Sediment, dewatering, metal adsorption
A study of shipping industry and assessment of environmental impacts in Turkey
(Thesis (M.S.) - Bogazici University. Institute of Environmental Sciences, 1998., 1998.) Tuzcu, M. Fikret.; Kocasoy, Günay.
In recent years, the importance of the environmental concerns at shipping and the related standards/safety measures have become subject to clear understanding and acceptance of each country at international platforms. The aim of this study was to evaluatelinvestigate the reflections of the international standardization developments at Turkey and the ways for reaching the very strict and internationally requested standards at her shipping industry at once. For this purpose; general evaluation of the prospective Turkish Shipping Industry, its development during the recent years, its current performance in the terms of conforming with the international standards and ways for reaching these standards with a better conformance have been investigated. The necessary steps that Turkey should immediately take during this period have been evaluated by specifically studying the problems of the Turkish Ports that can be defined as evident indicators of the economic power of a country. The results were expressed by analyzing the economic, commercial and technological means of overcoming the sub standardization at Turkish ShippingIPorts. Moreover, 'Pipe-Line' alternative has been suggested instead of 'Straits' alternative with social cost/benefit analysis of marine pollution and other environmental effects that have been studied by evaluating the effects of tanker accidents on environment and human nature.
Reuse of textile dyebaths by treatment with advanced oxidation
(Thesis (M.S.) - Bogazici University. Institute of Environmental Sciences, 1998., 1998.) Tezcanlı, Gökçe.; İnce, Nilsun.
The urgent need to conserve, recycle, and reuse the limited water resources of the earth has forced mankind to research and develop new methods and technologies for treating and managing used waters from process, cooling and/or rinse facilities of industrial applications. This is especially important in textile dyeing and finishing industries, where huge amounts of water are consumed in dyeing and washing/rinsing ofthe fabrics. The purpose of this study was to investigate the reusability of dyebath effluents in a textile batch dyeing process, by a homogeneous advanced oxidation system, involving H20 2 and ferrous sulfate in the presence and absence of UV-light. Synthetic dye bath effluents were prepared using a reactive azo-dye, Procion Red HE-7B, which was selected as a model compound for its wide use in the industry. Effectiveness of the system was tested by monitoring the degree of color and total organic carbon degradation. Parameters such as chemical oxygen demand and total dissolved solids were also monitored. Reusability of the treated water was tested in a dyehouse with various azo dyes. Under the experimental conditions employed, it was found that complete color removal and 71 % total organic carbon degradation is possible in 20 min of UV irradiation. The treated effluent was found to be reusable in cotton batch dyeing, yielding satisfactory dye quality on the fabric. Estimated cost of reusing dyebath effluents after treatment with the proposed technique was found to be 1.54 per m3 • The corresponding cost of using commercial water supply was estimated to be 2.42 per m3.
Trace-level metals and natural organic matter interactions: |oxidative/adsorptive removal pathways
(Thesis (M.S.) - Bogazici University. Institute of Environmental Sciences, 1999., 1999.) Uyguner, Ceyda Senem.; Bekbölet, Miray.
The destructive removal of humic acids in natural waters has gained increased attention, because these substances are known to be major precursors of carcinogenic disinfection byproducts which are produced during chlorination. Since the conventional treatment methods are expensive and complicated, heterogeneous photocatalytic degradation processes using Ti02 have been applied as an alternative treatment for the destruction of humic acid. This study was conducted to investigate the effects of chromium and manganese ions on the photocatalytic degradation of humic acid (10 mg L-1 ) in aqueous medium at neutral pH conditions (pH=6.7). Bench scale experiments were carried out using titanium dioxide (0.25 mg mL-1 ) as the photocatalyst and Black Light Fluorescent Lamp as the irradiation source. For comparison purposes, the photocatalytic degradation of humic acid was performed both in the presence and absence of metal ions. The degradation was followed by pseudo first order and Langmuir-Hinshelwood kinetics in terms ofColor436, Color4oo, UV280 and UV 254. The presence of chromium and manganese ions resulted in decreased removal rates on the photocatalytic degradation of humic acid compared to the baseline rate of humic acid alone. Pseudo first order reaction rate constants for Color436 and UV254 were found to be 3.86x10-2 min-1 and 2.73x10-2 min-1 in the absence of metal ions. Color436 removal rate constant decreased to 3.13x10-2 min-1 in the presence of 0.10 mg L-1 chromium ion and in the presence of 0.05 mg L-I manganese ion, a value of 3.37xlO-2 min-1 was attained. On the other hand, a similar trend was observed for UV254, the removal rate constant in the presence of chromium was calculated to be the lowest with a value of 2.06x10-2 min-1 whereas, in the presence of manganese it was found to be 2.31xlO-2 min-I. The decrease in the photocatalytic oxidation rate might be explained by the formation of a weak complex between humic acid and the metal ion which might have blocked the active sites on the Ti02 surface. Complimentary adsorption experiments were also performed to evaluate the effect of adsorption intensity on the photocatalytic degradation rates. The results indicated that no significant difference was observed with the adsorption capacity (KF) values, but compared to the other two, the humic acid + manganese system exhibited the highest values.
Deretmination of the remaining stabilization potential of landfilled solid waste by sludge addition
(Thesis (M.S.)- Bogazici University. Institute of Environmental Technology, 1999., 1999.) Güleç, Şükran Başak.; Onay, Turgut T.
Research activities on the innovative landfill management techniques are becoming attractive research areas in the last decades due to increasing amounts of solid waste by increasing industrialization and urbanization. In these landfill management techniques, determination of the stabilization potential of solid waste and the degree of stabilization at the site play important role because the degree and rate of stabilization in a landfill can be valuable parameter for future predictions of leachate and gas generation, determination of the feasibility of a landfill methane recovery program, evaluation of the closure time and the final use of the site. In this study, the remammg stabilization potential of solid waste retrieved from an operating landfill was investigated by the anaerobic digestion of the waste with anaerobically digested sludge with differing sludge:waste ratios. Four reactors were placed in a temperature controlled aquarium and loaded with different sludge:waste ratios in order to determine the remaining stabilization potential, to find the optimum ratio for the highest methane yield and to investigate the use of sludge as an enhancement technique for the waste degradation. The results of the study suggested that the addition of anaerobically digested sludge was an effective technique for the enhancement of solid waste degradation. Among the different sludge:waste ratios, the highest ratio 1:4 was found the optimum one for the enhancement and for the methane production in the study. The remaining stabilization potential of the retrieved solid waste was determined as 7% at the end of the study.
Dynamic simulation model for long term comprehensive environmental analysis of GAP
(Thesis (Ph.D.)- Bogazici University. Institute of Environmental Sciences, 1999., 1999.) Saysel, Ali Kerem.; Yenigün, Orhan.; Barlas, Yaman.
Integrated development projects based on water resources development, aiming hydropower production and agricultural modernization have many potential impacts on social and natural environments. Southeastern Anatolian Project (GAP), located in Southeast Turkey, comprising 10% of Turkish lands, targeting irrigation schemes on 1.7 million hectare fertile lowlands and 7400 MW hydropower production on Euphrates and Tigris would have many social and environmental consequences. In this study, potential environmental problems suggested by GAP, questions related with utilization of water resources, land degradation, agricultural pollution and land use are analyzed in systems perspective, focusing on the integrity of environmental, social and economic issues. With this aim, GAP S 1M, a dynamic simulation model is developed to trace long term trajectories of selected parameters, representing the relevant aspects of GAP's social, economic and natural environment. Based on a "systemic" problem definition, GAPSIM simulates the development rate of irrigation schemes, hydropower production with respect to changing irrigation releases, water availability on farmlands, crop selection and production, salinization, erosion, pesticide and fertilizer consumption, rangeland and forest quality, urbanization and population dynamics in GAP during 1990-2030 period, which comprises water facilities construction process. GAPSIM is validated, first "structurally", according to the validation tests suggested by the literature and then, model "behavior" is calibrated with respect to data available for the period 1990-1998. GAPSIM provides a dynamic simulation platform where several scenarios and policy analyses concerning GAP environment can be executed in order to arrive at an improved understanding of GAP as a socio-environmental system. Scenario and policy runs on GAPSIM reveal that, increased intensity of the most evapotranspirant crop cotton on GAP fields may cause significant water scarcity, which hinders the development rate of irrigation into new acres and inhibits crop yields by decreased water delivery to individual farms.
Powdered activated carbon addition to activated sludge in the treatment of landfill leachate
(Thesis (M.S.) - Bogazici University. Institute of Environmental Engineering, 1999., 1999.) Aktaş, Özgür.; Çeçen, Ferhan.
Powdered activated carbon (PAC) addition to activated sludge is a convenient method in the treatment of wastewaters that contain high amounts of nonbiodegradable and inhibitory organics. In the biological treatment of leachate in combination with domestic wastewater, leachate constituents may exert adverse effects on the efficiency of the activated sludge process. The purpose of this study was to investigate the effectiveness and applicability of PAC added activated sludge systems in the treatment of leachate in combination with synthetic domestic wastewater. The first step in the experimental path of the study was the determination of adsorption characteristics of the activated carbon used in the study. The succeeding steps involved the biological treatment studies in PAC added activated sludge reactors. The second step was treatment of leachate in batch reactors. The third step was treatment in Semi-Continuously Fed Batch reactors which were used to simulate the Continuous-Flow Stirred Tank: Reactor (CFSTR). The fourth step was PAC addition to a continuous-flow activated sludge reactor. The results of the study demonstrated that PAC addition to activated sludge is a promising method for the treatment of leachate in combination with domestic wastewater. PAC addition resulted in considerable reductions in the effluent concentrations of organic matter due to the adsorption of nonbiodegradable organics. It was found that the removal of organic matter was a simple combination of adsorption and biodegradation in the PAC added activated sludge systems for the conditions encountered in this study. Also, bioregeneration of activated carbon hypothesis was not valid. But, PAC addition increased nitrification rates through the enhancement of nitrifier activities by adsorbing the inhibitory and/or toxic compounds in the leachate.
Biodiversity analysis of marine demersal invertebrate fauna in the princess islands region
(Thesis (M.S.) - Bogazici University. Institute of Environmental Sciences, 1999., 1999.) Hüseyinoğlu, Fatih.; Furman, Andrzej.
A study for the inventory of the diversity of invertebrate species habited in the Princess Islands region, istanbul was conducted to cover the gap between alike studies conducted all over the top biodiversity centres. The mentioned area was one of the most diverse areas in temperate waters. The biodiversity due to over population has been decreased in the area, and this study was made in comparison with the past study. Princess Islands region and Bosphorus Strait was studied in detail in 1952 by Muzaffer Demir, which was the starting point for this comparative study in the area after half a century. Between Muzaffer Demir and this study, the studies conducted over invertebrate fauna in the Sea of Marmara are insufficient. The main concepts as the definitions, value and conservation of biodiversity are also given followed by the key notions of the current trends in conservation biology. Descriptions of the new species and keystone species with their pictures are also added. There are two groups of islands: Inhabited and desolate (see Map3.1 and Map 3.2). The inhabited islands are 6km far from the shore and domestic wastes are discharged directly to the sea. The desolate islands are 12km far from the shore and comparably have greater biodiversity than the inhabited islands coasts which are being polluted both by istanbul wastes because they are nearer and domestically. Several dives were done in various sites to observe the species in their habitats. Comparative which-and-where tables of the demersal invertebrate phyla are added with a scale of abundance that will help future studies. 9 new species were recorded that were not recorded before, and many probable extinctions were noted.
Evaluation of in situ leachate management alternatives on municipal solid waste stabilization in sanitary landfills
(Thesis (M.S.) - Bogazici University. Institute of Environmental Sciences, 1999., 1999.) San, İrem.; Onay, Turgut T.
An alternative approach for treating municipal solid waste involves the treatment of the waste after landfilling by addition of moisture to the waste. Increasing attention is being given to municipal solid waste landfill leachate recycle (recirculation) as a means of in situ leachate treatment and landfill stabilization. Using a leachate recycle, a landfill may be operated as a municipal solid waste bioreactor treatment system rather than as a conventional waste dumping site. In order to study the feasibility of an in situ leachate management alternative to provide leachate treatment and waste stabilization two landfill simulating reactors, one with leachate recycle and one without, were constructed and sited in the laboratory's hot room (34°C). Leachate recirculation volume and frequency of recirculation were changed periodically to investigate the effects of different operational moisture regimes on waste stabilization and leachate treatment. Both reactors were filled with municipal solid waste having typical solid waste composition determined in Istanbul. This research showed that the leachate recirculation is a feasible way to treat the leachate in situ, and, therefore, decrease the cost of further external treatment. Leachate recirculation management strategy accelerates the stabilization rate of waste matrix, decreasing time required for stabilization to a matter of months rather than years. Four times per week recirculation strategy was found to provide highest degree of waste stabilization.|Keywords: leachate recirculation, landfill stabilization

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