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This study focuses on the impact of the disposal of Tirunelveli city municipal waste in the quality of groundwater in Ramayanpatti village where the waste is disposed; the study also assesses the quality of the groundwater suitability in irrigation in the disposed region. Tirunelveli city generates municipal waste of nearly 15 MLD of domestic wastewater and 100 tons of solid waste in a day. The domestic wastewater is treated by waste stabilization pond. The solid waste is dumped in the open yard. These two disposal sites are located in the Ramayanpatti area and their boundaries are at a distance of 500m from each other. Ground water resources are extracted in use for agriculture in the area of Ramayanpatti. Around thirty, locations have been identified in the Ramayanpatti area for sampling, based on the contour and flow direction. The dominant chemical cation species in the majority of the groundwater samples are in the order of Na>Ca>Mg>K and anion species are in the order of HCO3>Cl>SO4>NO3. Gibbs plot shows that the region is dominated by evaporation and dilution phenomenon. Rhode’s plot shows that there is no reduction in the rate of infiltration of soil in the Ramayanpatti region. Dendrogram shows that the leachates infiltration is predominant in the winter season. The study shows that the groundwater quality, nearer and to the southeastern side of the disposal sites are most affected and contaminated by solid waste leachates. The inference with various irrigation plots show that the quality of groundwater in the southeastern region is doubtful for use in irrigation and the groundwater needs to be assessed in order to use in irrigation for agriculture.

Presence of metals even at trace levels in natural waters pose sever health risks. Heavy metals are introduced to coastal and marine environments through a variety of sources and activities including sewage and industrial effluents where Black Sea is not different. However, metals behave differently in Black Sea as it an enclosed body. Coastal areas of Turkey face great challenges due to heavy metal contamination caused by rapid urbanization and industrialization. The aim of this study was to investigate the spatial and temporal distributions of total mercury (Hg) in seawater at the mid-Black Sea coast of Samsun, Turkey. The samples were collected from 13 monitoring stations, from the three distances in four seasons during the year 2013. The samples were analyzed for physicochemical parameters along with contamination and enrichment factors. The distribution of Hg is nearly random along the studied coast but obtained values ranges from 0.57 to 12.6 μg/L with an average of 5.24 μg/L were above permissible limits. It was observed that number of samples collected during wet seasons (winter and autumn) with Hg were higher. High enrichment factor 0.331 and contamination factor 25.2 was recorded. Hg present at sampling station M27 was due to point source, a possible ship activity indicated by enrichment factor. The sources responsible for water pollution with Hg are mainly municipal and industrial effluents, leaching, agricultural and pasturage runoff and oil spills. Furthermore, due to unique hydrography of Black Sea, risk of Hg accumulation is high. Interestingly, a direct relation between basicity and Hg concentration was observed. i.e. highest concentration was found on pH 8.33.

Currently, the ecosystem is being damaged in many rivers and subsequently the fish species living there are also facing decline or even extinction. This situation urges to model the habitat and to design suitable restoration strategies in order to increase the capabilities of ecological modeling. In this paper, we proposed a numerical model to assess the ecosystem habitat situation and investigated the impacts of two ecological restorations strategies for the target fish species. The model includes a hydrodynamic model, a habitat model and habitat restoration schemes. The hydrodynamic model simulated the flow properties while sediments in the riverbed were also surveyed. Based on these parameters and fish preference curves, the habitat suitability indices were calculated. In order to analyze the river habitat quality, the weighted usable areas and overall suitability index were also calculated and the effects of the restoration strategies on selected fish species (Freshwater Reeves shad - Tenualosa reevesii) in the Chin-sha River were evaluated. The two ecological restoration strategies: addition of side-channel (scheme I) and river bank reconstruction (scheme II) enhanced the Freshwater Reeves shad habitat suitability level, with the high suitability index proportion increasing from 19.5% to 33.1% for scheme I and to 36.1% for scheme II. Based on the modelling results, we concluded that our numerical model could potentially provide suitable scenarios for successful fish habitat restoration.

In the present work, the degradation of phenol from aqueous solutions was investigated using periodate/zero valent iron nanoparticle (nZVI) in the presence of ultrasound at a batch reactor. The Experimental tests were carried out using pre-designated amounts of nZVI, periodate, and pH ranging from 1-7 mM, 0.5-5 mM, 3-11 respectively. During the all experimental tests the ultrasonic reactor was operated at a fix frequency (40 kHz), temperature (33±1) and power (350 W). The results of nZVI/periodate/ultrasound system on degradation of phenol showed that the removal efficiency was frankly affected by the amount of produced free radicals to initiate the oxidative decomposition of phenol. As, with enhancing the nZVI loading to 3 mM and periodate concentration to 3 mM, the removal efficiency of phenol was increased. Besides, the acidic pH (pH=3) was found to be more effective than neutral and alkaline pH in degradation of phenol.