Adopting citizen science approach for water quality monitoring in Uzungöl, Turkey.

In the present study, adopting of citizen science approach for monitoring water quality of a lake (Uzungöl, Turkey) was investigated. The study consisted of selection of sampling points and water quality parameters, training of volunteers, sampling and analysis by volunteers, and development of a mobile application for data collection and storage. In the scope of the study, four measurement points around the lake were selected and elementary school students were trained both theoretically and practically to collect water quality data. During the project (June-December, 2018), volunteers collected water samples and measured temperature, pH, nitrate, and phosphate with the given test kits. The mobile application was developed using open source code and used to collect and store the volunteer data. According to the volunteer data, temperature values were between 8.5 and 15.5 °C, pH values were between 2 and 8.5, nitrate values were between 0.5 and 2.5 mg/L, and phosphate values were between 0.5 and 5 mg/L in the lake. Most of the pH and temperature results were compatible with field measurements done by research group during field visits. The motivation of the volunteers and mobile application development were the achievements of the project. Low number of the data and its reliability were the main limitations. Therefore, this study showed that citizen science has both capabilities and constraints for collection of water quality data, however; outstanding potential of citizen science is obvious.

Evaluation of Trace Element Contamination and Health Risks of Medicinal Herbs Collected from Unpolluted and Polluted Areas in Sichuan Province, China.

Trace element contamination in Chinese herbal medicines has been recognized as a potential health concern for consumers. To assess the health risk to the herb-consuming population, nine trace elements (Cu, Cd, Cr, Mo, Ni, Pb, Sr, Zn, and As) were investigated based on their concentrations in three common medicinal plants (Astragalus membranaceus, Codonopsis tangshen, and Paris polyphylla var. chinensis) and soils from unpolluted and polluted areas in the Sichuan Province, China. The results showed that the metal content differed significantly in medicinal plants and soils from unpolluted versus polluted areas. No significant differences in metal accumulation were observed for these CHMs grown in either unpolluted or polluted areas. Evaluation of the health risk index suggested that soil ingestion and medicated diet represented the dominant exposure routes, indicating that trace metal(loids) in local soil might pose potential risks through soil-food chain transfer. Hazard quotient values for AM (1.473) and CT (1.357) were higher than the standard value (HQ > 1), whereas the hazard indices for PC, AM, and CT were 13.18, 14.33, and 14.01 times higher than the safe limit (HI > 1) in the polluted area, indicating non-cancer-related health hazards. Ingestion of soil was responsible for 36.39 to 91.06% of the total cancer risk and medicated diet accounted for 6.35 to 62.71%, compared with inhalation and dermal contact, suggesting carcinogenic health risks in herbs from polluted soils. In this study, Pb showed relatively higher non-carcinogenic risks, while Cr and Ni posed the highest cancer risks. Therefore, we propose more effective measures, which should be considered for Cr, Ni, and Pb remediation in soil to reduce their pollution in the studied areas.

The potential of Turkey's province-based livestock sector to mitigate GHG emissions through biogas production.

Methane and nitrous oxide are the two leading greenhouse gases (GHG) that are released to the atmosphere due to livestock enteric fermentation and manure management. This study examines Turkey's province-based GHG emissions released by its livestock sector due to these processes. Besides, this study focusses on biogas production through anaerobic digestion, which is one of the most effective GHG mitigation options from manure management. This study aims to show the importance of the livestock sector in regards to GHG emissions in Turkey based on estimations made by the Intergovernmental Panel on Climate Change (IPCC) 2006 Guidelines. As a result of these estimations, for the year 2015, 33.85 million tons of carbon dioxide equivalent (CO2-eq) were produced from enteric fermentation and manure management system. The study also aims to evaluate Turkey's province-based biogas production potential from animal manure through the anaerobic digestion (AD) technology. Two different biogas potential scenarios with varying manure recovery rates were developed. Scenario 1 was developed based on the assumption of that total amount of produced animal manure would be used in AD for biogas production, and scenario 2 was developed based on the realistic manure recovery rates that vary with the type of livestock. Biogas potentials for scenario 1 and scenario 2 were determined as 8.41 billion m3 and 4.18 billion m3 in 2015, respectively. These values can meet Turkey's total electricity demand at a rate of 5.25% for scenario 1, and the rate of 2.3% for scenario 2. In addition, according to Turkey's GHG Inventory, submitted annually to the United Nations Framework Convention on Climate Change (UNFCCC), GHG emissions from manure management can be reduced by 1.13% through biogas production.

Treatment of landfill leachate with laboratory scale vertical flow constructed wetlands: plant growth modeling.

The main purpose of this study was to investigate the removal of ammonia, orthophosphate, and COD present in landfill leachate using vertical subsurface flow constructed wetland systems (VFCW). The effect of different types of plants (Typha latifolia and Canna indica) in the removal of pollutants was also investigated. The systems were operated identically at a flow rate of 5 l/day and a hydraulic retention time (HRT) of 22 days in the T. latifolia reactor (R1), C. indica reactor (R2), and Control reactor (R3). Concentration-based average removal efficiencies for R1, R2, and R3 were NH4-N; 60.0%, 56.0%, and 46, COD; 81.0%, 84.0%, and 79.0%, PO4-P; 45.0%, 46.0%, and 32.0%, respectively. These results show that the model is a good predictive tool for determining the plant lengths using the growth equations. It is also revealed that the Logistic and Cubic models are suitable for the R1 and R2 reactors.

Influence of Hydraulic Retention Time and Reactor Configuration During Fermentation of Diluted Chicken Manure.

In this study, single-stage and two-phase semi-continuous thermophilic anaerobic reactors fed with diluted (3 % total solids (TS) and 1.8 % volatile solids (VS)) chicken manure at three different hydraulic retention times (HRTs) were compared interms of biogas production rate, methane content of the produced biogas, and VS and TS removal. Along the study, HRTs of 16, 12, and 8 days were implemented to the single-stage and the two-phase systems. It was observed that the single-stage anaerobic system was superior to the two-phase anaerobic system according to their biogas production rates (517 vs. 356, 551 vs. 359, 459 vs. 386 (mL/g VSfeed)) at all HRTs. On the other hand, methane content of the biogas produced was higher in the two-phase system compared to the single-stage system.

Comparative evaluation of biogas production from dairy manure and co-digestion with maize silage by CSTR and new anaerobic hybrid reactor.

This study aimed to investigate potential methane production through anaerobic digestion of dairy manure and co-digestion with maize silage. Two different anaerobic reactor configurations (single-stage continuously stirred tank reactor [CSTR] and hybrid anaerobic digester) were used and biogas production performances for each reactor were compared. The HR was planned to enable phase separation in order to improve process stability and biogas production under higher total solids loadings (≥4%). The systems were tested under six different organic loading rates increased steadily from 1.1 to 5.4 g VS/L.d. The CSTR exhibited lower system stability and biomass conversion efficiency than the HR. The specific biogas production of the hybrid system was between 440 and 320 mL/gVS with 81-65% volatile solids (VS) destruction. The hybrid system provided 116% increase in specific biogas production and VS destruction improved by more than 14%. When MS was co-digested together with dairy manure, specific biogas production rates increased about 1.2-fold. Co-digestion was more beneficial than mono-material digestion. The hybrid system allowed for generating methane enriched biogas (>75% methane) by enabling phase separation in the reactor. It was observed that acidogenic conditions prevailed in the first two compartments and the following two segments as methanogenic conditions were observed. The pH of the acidogenic part ranged between 4.7 and 5.5 and the methanogenic part was between 6.8 and 7.2.

Biogas production from chicken manure at different organic loading rates in a mesophilic-thermopilic two stage anaerobic system.

This study investigates the biogas production from chicken manure at different organic loading rates (OLRs), in a mesophilic-thermophilic two stage anaerobic system. The system was operated on semi continuous mode under different OLRs [1.9 g volatile solids (VS)/L·d - 4.7 g VS/L·d] and total solid (TS) contents (3.0-8.25%). It was observed that the anaerobic bacteria acclimatized to high total ammonia nitrogen concentration (>3000 mg/L) originated as a result of the degradation of chicken manure. High volatile fatty acid concentrations were tolerated by the system due to high pH in the reactors. The maximum average biogas production rate was found as 554 mL/g VSfeed while feeding 2.2 g VS/L-d (2.3% VS - 3.8% TS) to the system. Average methane content of produced biogas was 74% during the study.

Comparison of horizontal and vertical constructed wetland systems for landfill leachate treatment.

The main purpose of this study was to treat organic pollution, ammonia and heavy metals present in landfill leachate by the use of constructed wetland systems and to quantify the effect of feeding mode. The effect of different bedding material (gravel and zeolite surface) was also investigated. A pilot-scale study was conducted on subsurface flow constructed wetland systems operated in vertical and horizontal mode. Two vertical systems differed from each other with their bedding material. The systems were planted with cattail (Typha latifolia) and operated identically at a flow rate of 10 l/day and hydraulic retention times of 11.8 and 12.5 day in vertical 1, vertical 2 and horizontal systems, respectively. Concentration based average removal efficiencies for VF1, VF2 and HF were NH(4)-N, 62.3%, 48.9% and 38.3%; COD, 27.3%, 30.6% and 35.7%; PO(4)-P, 52.6%, 51.9% and 46.7%; Fe(III), 21%, 40% and 17%, respectively. Better NH(4)-N removal performance was observed in the vertical system with zeolite layer than that of the vertical 2 and horizontal system. In contrast, horizontal system was more effective in COD removal.

The effect of an anoxic zone on biological phosphorus removal by a sequential batch reactor.

Nitrate can affect phosphate release and lead to reduced efficiency of biological phosphorus removal process. The inhibition effect of remaining nitrate at the anaerobic/anoxic phases was investigated in a lab scale sequencing batch reactor. In this study the influence of denitrification process on reactor performance and phosphorus removal was examined. The experiments were carried out through simultaneous filling and decanting, mixing, mixing-aeration and settling modes. Glucose and acetate were used as carbon sources. The proposed treatment system was capable of removing approximately 80% of the influent PO4-P, 98% NH4-N and 97% COD at a SRT of 25 days. In the fill/decant phase, anoxic and anaerobic conditions prevailed and a large quantity of nitrate was removed in this stage. In the anoxic phase the remaining nitrate concentration was quickly reduced and a considerable amount of phosphate was released. This was attributed to the availability of acetate in this stage. For effective nitrogen and phosphate removal, a short anoxic phase was beneficial before an aerobic phase.