Suspended particulate matter estimates using optical and acoustic sensors: application in Nestos River plume (Thracian Sea,North Aegean Sea)

The present study investigates the use of combined methods of optical and acoustic sensors, in collaboration with direct in situ measurements, for the calibration and validation of a model transforming acoustic backscatter intensity series into suspended particulate matter (SPM) concentration datasets. The model follows previously elaborated techniques, placing particular attention to the parameterization of the acoustic absorption index as a function of water physical properties. Results were obtained from the annual deployment (during 2007–2008) of an upward-facing acoustic Doppler current profiler (ADCP) (307 kHz), equipped with a Wave Array, and an optical backscatter sensor (OBS), at the bottom of Thassos Passage near Nestos River plume (Thracian Sea, Northern Greece). The OBS was calibrated through linear regression, using 2007 and 2012 field sampling data, exhibiting an error of 13–14 % due to chlorophyll presence. The ADCP signal was calibrated through simultaneous measurements of backscatter intensity and turbidity profiles. Harmonic analysis on the model-produced SPM concentrations explained the tidal influence on their variability, especially during the summer. Empirical orthogonal functions analysis revealed the impact of waves and wave-induced currents on SPM variability. Finally, Nestos River sediment load was found uncorrelated to the SPM change in Thassos Passage, due to the dispersal and sediment deposition near the river mouth.     

Open burning and open detonation PM10 mass emission factor measurements with optical remote sensing

Emission factors (EFs) of particulate matter with aerodynamic diameter ≤10 µm (PM₁₀) from the open burning/open detonation (OB/OD) of energetic materials were measured using a hybrid-optical remote sensing (hybrid-ORS) method. This method is based on the measurement of range-resolved PM backscattering values with a micropulse light detection and ranging (LIDAR; MPL) device. Field measurements were completed during March 2010 at Tooele Army Depot, Utah, which is an arid continental site. PM₁₀ EFs were quantified for OB of M1 propellant and OD of 2,4,6-trinitrotoluene (TNT). EFs from this study are compared with previous OB/OD measurements reported in the literature that have been determined with point measurements either in enclosed or ambient environments, and with concurrent airborne point measurements. PM₁₀ mass EFs, determined with the hybrid-ORS method, were 7.8?×?10^?3 kg PM₁₀/kg M1 from OB of M1 propellant, and 0.20 kg PM₁₀/kg TNT from OD of TNT. Compared with previous results reported in the literature, the hybrid-ORS method EFs were 13% larger for OB and 174% larger for OD. Compared with the concurrent airborne measurements, EF values from the hybrid-ORS method were 37% larger for OB and 54% larger for OD. For TNT, no statistically significant differences were observed for the EFs measured during the detonation of 22.7 and 45.4 kg of TNT, supporting that the total amount of detonated mass in this mass range does not have an effect on the EFs for OD of TNT.

Implications: Particulate matter (PM) in the atmosphere affects the health of humans and ecosystems, visibility, and climate. Fugitive PM emissions are not well characterized because of spatial and temporal ubiquity and heterogeneity. The hybrid-ORS method is appropriate for quantifying fugitive PM emission factors (EFs) because it captures the spatial and temporal dispersion of ground level and elevated plumes in real time, without requiring numerous point measurement devices. The method can be applied to provide an opportunity to reduce the uncertainty of fugitive PM EFs and readily update PM emissions in National Emission Inventories for a range of fugitive PM sources.     

A multi-objective programming model for assessment the GHG emissions in MSW management

In this study a multi-objective mathematical programming model is developed for taking into account GHG emissions for Municipal Solid Waste (MSW) management. Mathematical programming models are often used for structure, design and operational optimization of various systems (energy, supply chain, processes, etc.). The last twenty years they are used all the more often in Municipal Solid Waste (MSW) management in order to provide optimal solutions with the cost objective being the usual driver of the optimization. In our work we consider the GHG emissions as an additional criterion, aiming at a multi-objective approach. The Pareto front (Cost vs. GHG emissions) of the system is generated using an appropriate multi-objective method. This information is essential to the decision maker because he can explore the trade-offs in the Pareto curve and select his most preferred among the Pareto optimal solutions. In the present work a detailed multi-objective, multi-period mathematical programming model is developed in order to describe the waste management problem. Apart from the bi-objective approach, the major innovations of the model are (1) the detailed modeling considering 34 materials and 42 technologies, (2) the detailed calculation of the energy content of the various streams based on the detailed material balances, and (3) the incorporation of the IPCC guidelines for the CH₄ generated in the landfills (first order decay model). The equations of the model are described in full detail. Finally, the whole approach is illustrated with a case study referring to the application of the model in a Greek region.     

Influence of soil inorganic amendments on heavy metal accumulation by leafy vegetables

Environmental Science and Pollution Research - The present study aims to assess the effect of four inorganic soil amendments, such as lime (CaCO3), red mud consisting of 75% hematite (Fe2O3),...     

Re-Establishing a Sustainable Wetland at Former Lake Karla,Greece, Using Ramsar Restoration Guidelines

Lake Karla, Greece, was almost completely drained in 1962 both to protect surrounding farmlands from flooding and to increase agricultural area. Loss of wetland functions and values resulted in environmental, social, and economic problems. A number of restoration plans were proposed to address these problems. The plan approved by the government in the early 1990s proposed construction of a 4200-ha reservoir solely to improve water storage and flood attenuation functions. However, the Ramsar Scientific and Technical Review Panel states that the primary goal of any restoration project is to create resilient and sustainable ecosystems, as measured on a human timescale, in order to improve the ecological character and enhance the socioeconomic role that the wetland plays in the watershed. This study utilizes Ramsar guidelines for sustainable restoration of Lake Karla. Eight additional restoration measures are proposed based on functional analysis of the wetland to enhance additional wetland functions and support multiple values for humans and nature.