Evaluation of heavy metal content in digestate from batch anaerobic co-digestion of sunflower hulls and poultry manure

In this experimental study, the biogas digestate from mesophilic batch anaerobic co-digestion of poultry manure and an agricultural residue, sunflower hulls, was characterized, particularly in terms of heavy metal content, in order to evaluate whether the biogas digestate was suitable for land applications. Ni, Zn, Cu, Pb, Cr, Cd, and Hg were detected in the biogas digestate in each trial, however, their concentrations were always lower than the limit values stated in Turkish regulations. The main source of heavy metals in the biogas digestate seemed to be the poultry manure, not the agricultural residue. The commercial feedstuffs that are frequently supplemented with various essential elements to promote optimum nutrient supply and optimum growth rates may have contributed to heavy metals presence in the biogas digestate. The results indicated that the biogas digestate from anaerobic co-digestion of manure and agricultural residue could be utilized as fertilizer in agricultural applications.     

Feasibility of incorporating waste grass clippings (Lolium perenne L.) in particleboard composites

This study investigated some of the important physical (thickness swelling) and mechanical (modulus of rupture, modulus of elasticity and internal bond) properties of single-layer particleboard panels made from eucalyptus (Eucalyptus camaldulensis Dehn.), waste of grass clippings (Lolium perenne L.) and combinations of the two. The chemical properties (pH, holocelluse and alpha cellulose contents, and water, alcohol-benzene and 1% sodium hydroxide solubilities) of the raw materials were also determined. Panels with a 6:94 ratio of grass-to-eucalyptus particles had the required mechanical properties for interior fitments including furniture and general uses. Boards manufactured with 100% grass clippings exhibited the lowest quality. The overall panel properties improved with a lower percentage of grass clippings added. Based on initial results, it also appears that grass should compose no more than 13% to achieve acceptable panel properties for interior fitments and general uses.     

Monitoring of Heavy Metal Pollution of Groundwater in a Phreatic Aquifer in Mersin-Turkey

In this study, heavy metal contents of groundwater from the Mersin aquifer were determined with photometric methods and used to determine the main factors controlling the pollution of groundwater in the area. Using MapInfo GIS software, spatial analysis and integration were carried out for mapping drinking water quality in the basin. From the photometric heavy metal analysis, it is inferred that the excess concentration of Fe, Ni, Mn, Mo and Cu at some locations is the cause of undesirable quality for drinking purposes. Similarly, the EC thematic map shows that considerable areas in the basin are having high salinity hazards. The reason for excess concentration of various heavy metals is the industrial activities and petroleum pipelines and salinity levels show the sea water intrusion.     

Investigation of acute toxicity of chlorpyrifos-methyl on guppy Poecilia reticulata

Static bioassays were made to determine acute toxicity of chlorpyrifos-methyl, a wide spectrum organophosphorus insecticide and potential toxic pollutant of aquatic ecosystem, Guppy fish (Poecilia reticulata). Bioassays were made at a regulated temperature of 22+/-1 degrees C and were repeated three times. Lethal doses of the insecticides were determined using LC50 software programme of U.S. EPA based on Finney's Probit Analysis statistical method. The 96 h LC50 value and 95% confidence limit of chlorpyrifos-methyl for Guppy was estimated as 1.79 (1.47-2.10) mg/l. The fish exposed to chlorpyrifos-methyl exhibited behavioral changes in the form of neurotoxin toxicity: less general activity than control group, loss of equilibrium, erratic swimming and staying motionless at a certain location generally at mid-water level for prolonged periods. The 1 mg/l (lowest) concentration had similar behavior (NOEC) with the control group.     

Determination of biogas generation potential as a renewable energy source from supermarket wastes

Fruit, vegetable, flower waste (FVFW), dairy products waste (DPW), meat waste (MW) and sugar waste (SW) obtained from a supermarket chain were anaerobically digested, in order to recover methane as a source of renewable energy. Batch mesophilic anaerobic reactors were run at total solids (TS) ratios of 5%, 8% and 10%. The highest methane yield of 0.44 L CH₄/g VS_added was obtained from anaerobic digestion of wastes (FVFW + DPW + MW + SW) at 10% TS, with 66.4% of methane (CH₄) composition in biogas. Anaerobic digestion of mixed wastes at 5% and 8% TS provided slightly lower methane yields of 0.41 and 0.40 L CH₄/g VS_added, respectively. When the wastes were digested alone without co-substrate addition, the highest methane yield of 0.40 L CH₄/g VS_added was obtained from FVFW at 5% TS. Generally, although the volatile solids (VS) conversion percentages seemed low during the experiments, higher methane yields could be obtained from anaerobic digestion of supermarket wastes. A suitable carbon/nitrogen (C/N) ratio, proper adjustment of the buffering capacity and the addition of essential trace nutrients (such as Ni) could improve VS conversion and biogas production yields significantly.     

The history and evaluation of saltwater intrusion into a coastal aquifer in Mersin, Turkey

The Mersin-Kazanli region is a densely industrialized region. The factories and towns cover their water demand from groundwater. With the increased water demand, saltwater intrusion has occurred. The chloride concentration of the water samples from some wells has been analysed periodically since these wells were drilled. The results of these analyses and electrical conductivity measurements were used to show the history and development of saltwater intrusion up to the year 2000. The Cl(-) concentration of the water within the alluvial aquifer increased to over 3000 mg/l in 1999 and the wells were closed completely. In 2001 new wells were drilled more than 1 km away from the sea and old well field. With the results of the analyses conducted in 2001, the current groundwater quality was determined. The ground water is of the magnesium-calcium-bicarbonate type and this composition is controlled by the interaction of the water with the sediments of alluvial deposits.     

Determining the tourism potential of the Altındere Valley National Park (Trabzon/Turkey) with respect to its conservation value

This study was conducted to determine the tourism potential of Alt?ndere Valley National Park with respect to its conservation and utilization. With its natural values, Alt?ndere Valley National Park is one of the internationally prominent areas of potential for the recreational and touristic facilities it offers.

A mathematical method – criterion referenced method – was applied within this study, which was done to portray the touristic potential (resulting from the touristic and recreational utilization of the national park area and recreational zone) of the national park, which was visited by an average of 200,000 local and foreign guests.

According to this method, the conservation and utilization values that appear on two opposite axes were examined in accordance with the natural resource values of the area, and conservation and utilization values for each criterion were determined. Depending on the data, the general exploitable touristic potential of the area was specified.

A survey study was conducted on groups from various disciplines and local & foreign tourists visiting the area in specifying the touristic potential of the National Park. Eleven criteria were defined concerning the area and a criterion reference was prepared for each criterion. Then, conservation and utilization values for each criterion and exploitable touristic potential were mathematically indicated. The fact that the attained values were reduced to a percentage basis provides the opportunity to compare the researched area to similar fields that use the same method. Within the scope of the method, several suggestions were made using the information obtained in the evaluation of the data for every other source value.     

Cytogenetic biomonitoring of primary school children exposed to air pollutants: micronuclei analysis of buccal epithelial cells

There is an increasing attempt in the world to determine the exposures of children to environmental chemicals. To analyze the genotoxic effect of air pollution, micronucleus (MN) assay was carried out in buccal epithelial cells (BECs) of children living in an urban city of Turkey. Children from two schools at urban-traffic and suburban sites were investigated in summer and winter seasons for the determination of BEC-MN frequency (per mille) and frequency of BEC with MN (per mille). The same children were also recruited for lung function measurements within a MATRA project (“Together Towards Clean Air in Eskisehir and Iskenderun”) Measured NO₂ and SO₂ concentrations did not exceed the European Union (EU) limit levels either in urban-traffic or suburban regions. Higher O₃ concentrations were measured in the suburban site especially in the summer period. Particulate matter (PM_2.5 and PM₁₀) levels which did not differ statistically between two regions were above the EU limits in general. Although BEC-MN frequencies of children living in the suburban sites were higher in general, the difference between two regions was not significant either in the summer or winter periods. BEC-MN frequencies of the urban-traffic children were found to be significantly higher in summer period (mean ± SD, 2.68?±?1.99) when compared to winter period (1.64?±?1.59; p?=?0.004). On the other hand, no seasonality was observed for the suburban children. Similar results have been obtained in the BEC frequency with MN in our study. In summer, BEC-MN frequencies were significantly increased with the decrease in pulmonary function levels based on forced expiratory flow between 25 and 75 % of vital capacity (FEF_25–75 %) levels (p?<?0.05). As a conclusion, children living in urban-traffic and suburban areas in the city of Eski?ehir exhibited similar genotoxicity. Seasonal variation in genotoxicity may be interpreted as relatively high ozone levels and increasing time spent at outdoors in the summer.     

An expert system for the quantification of fault rates in construction fall accidents

Introduction. Expert witness reports, prepared with the aim of quantifying fault rates among parties, play an important role in a court's final decision. However, conflicting fault rates assigned by different expert witness boards lead to iterative objections raised by the related parties. This unfavorable situation mainly originates due to the subjectivity of expert judgments and unavailability of objective information about the causes of accidents. As a solution to this shortcoming, an expert system based on a rule-based system was developed for the quantification of fault rates in construction fall accidents. The aim of developing DsSafe is decreasing the subjectivity inherent in expert witness reports. Methodology. Eighty-four inspection reports prepared by the official and authorized inspectors were examined and root causes of construction fall accidents in Turkey were identified. Using this information, an evaluation form was designed and submitted to the experts. Experts were asked to evaluate the importance level of the factors that govern fall accidents and determine the fault rates under different scenarios. Based on expert judgments, a rule-based expert system was developed. The accuracy and reliability of DsSafe were tested with real data as obtained from finalized court cases. Result. DsSafe gives satisfactory results.     

Monitoring and assessment of airborne Cladosporium Link and Alternaria Nées spores in Sivrihisar (Eskisehir), Turkey

The spores of Cladosporium spp. and Alternaria spp., commonly described as the most allergenic spores, were collected by means of Durham gravimetric sampler from the Sivrihisar (Eskisehir) atmosphere throughout 2005 to 2006. The weekly variations in spores/cm(2) of Cladosporium and Alternaria were recorded. During this period, a total of 6,198 spores belonging to Cladosporium spp. and Alternaria spp. were recorded. Of these spores, 2,969 were identified in 2005 and 3,229 in 2006. While 69.55% of the total spores were those of Cladosporium spp., 30.45% were Alternaria spp. Relationships between airborne fungal spore presence and weather conditions were examined statistically. A Shapiro-Wilk test revealed that the airborne spores of Cladosporium spp. and Alternaria spp. had a normal distribution. Following this, Chi-square test, t test and Pearson correlation analysis were performed. The effects of temperature and relative humidity on the spore numbers of Cladosporium spp. and Alternaria spp. were significant according to the month in which they were collected (p < 0.01). The spore concentrations of each species reached to their highest levels in June 2006.