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The focus of this study is to examine the short‐ and long‐term causal effects of natural disaster shocks on the stock market and business confidence level in the time‐frequency domain by studying the co‐movements between earthquake data and the Istanbul Stock Index closing prices, using the Wavelet Coherence and Phase Difference analyses. The empirical findings reveal that the relationship between earthquake events and financial markets is not stable over time and across different time horizons. The linkage becomes stronger in the long term when the impact of the earthquake event coincides with a financial crisis reflecting a combined effect. This nexus is also strong during the years 2007–2011 reflecting a similar combined effect of both an earthquake event and the global financial crisis. Meanwhile, co‐movement between the earthquake and the financial market index implies a negative effect in the period 2011–2012, indicating short‐run effects of stock market shocks. Differentiating these short‐term and long‐term effects has implications for risk management and policymaking. [ABSTRACT FROM AUTHOR]

The transport pathways and exchange characteristics of the Kamil Abdüş Lagoon in Istanbul, Turkey, are simulated using a finite element model with a Lagrangian particle tracking module. The lagoon is in the process of being reconfigured. The simulations are performed using a draft configuration. The effect of winds and the number of particles on the e-folding time is simulated. Results show that the lagoon is strongly dominated by winds with a correlation coefficient of 0.897 between the wind and residual current magnitudes. The lagoon e-folds in 9.1 days under realistic winds and in 14.3 days when there is no wind with confidence levels of 5%. The Lagrangian study uses six simulations with particle numbers ranging between 65073 and 2730486. A methodology based on confidence levels is proposed. It is observed that approximately 784 000 particles are necessary to obtain 5% level of confidence. With a problematic history and new planning options, the lagoon has a potential to be used as an example setting, all-field study ground for anthropogenically engineered coastal ecosystems. [ABSTRACT FROM AUTHOR]

Marine waste management is crucial for Istanbul because of the significant location for intercontinental transition, international trade, tourism, industry and shipping. This study is the first one realised in Turkey for the detailed characterisation of marine waste. The amount and characteristics of solid wastes originating from beaches, coastlines, sea surface cleaning processes and ships (both cargo and cruise ships) were determined. It was observed that marine wastes includes a significant amount of recyclable materials. Although, it was ascertained that the amount and composition of waste differs according to the collecting sources, the majority of wastes are composed of different types of plastics. The average calorific value of marine waste was determined as 2500 kcal kg-1, which is higher than that of mixed municipal solid waste. There is a lack of studies on the pathways of disposal alternatives of marine waste after collection. As landfilling is the common pathway for disposal after collecting, it is clear that recycle/reuse and energy recovery options are possible for marine waste. [ABSTRACT FROM AUTHOR]

This study was carried out on two field scale test cells constructed at Odayeri Sanitary Landfill (OSL) located at the European side of Istanbul city. Approximately 11,000 tons of municipal solid wastes (MSW) were filled at equal quantities to each cell (C1 and C2). Leachate was periodically recirculated to one (C2) of the test cells in various quantities. These cells are compared in terms of leachate quality (pH, BOD and COD), methane potential (MP) of wastes and surface settlement for a monitoring period of 0-400 days. Experimental results showed that optimum pH for anaerobic decomposition was reached in a shorter period of time in C2 compared to C 1. Moreover, BOD and COD concentrations were decreased more rapidly in C2 cell than in C1 cell. BOD/COD ratio was determined as 0.25 and 0.17 for C1 and C2 cells consequently after 380 days from placement of refuse to the test cells. In MP tests, first order rate constants for cell C1 and C2 were found be 0.145 year-1 and 0.222 year-1, respectively. Topographic measurements revealed that cumulative settlements after 12 months from refuse placement were 0.49 and 0.70 m for C1 and C2 cells, respectively. According to results obtained from this study, it can be concluded that appropriate conditions can cause enhance in the decomposition rate of MSW. [ABSTRACT FROM AUTHOR]

Abstract: In this study we present a neural network model for predicting the methane fraction in landfill gas originating from field-scale landfill bioreactors. Landfill bioreactors were constructed at the Odayeri Sanitary Landfill, Istanbul, Turkey, and operated with (C2) and without (C1) leachate recirculation. The refuse height of the test cell was 5m, with a placement area of 1250m2 (25m×50m). We monitored the leachate and landfill gas components for 34 months, after which we modeled the methane fraction in landfill gas from the bioreactors (C1 and C2) using artificial neural networks; leachate components were used as input parameters. To predict the methane fraction in landfill gas as a final product of anaerobic digestion, we used input parameters such as pH, alkalinity, Chemical Oxygen Demand, sulfate, conductivity, chloride and waste temperature. We evaluated the anaerobic conversion efficiencies based on leachate characteristics during different time periods. We determined the optimal architecture of the neural network, and advantages, disadvantages and further developments of the network are discussed. [Copyright &y& Elsevier]