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Unicellular microalgal culture represents a new opportunity for producing significant biofuel quantities in the future along with other specialty products, due to several major advantages microalgae species present when compared to conventional crops, including much faster growth rates, cultivation in a variety of environments and photobioreactor systems, and almost 100% recycling of nutrients. In the current research, the scaling-up of the cultivation of Chlorella vulgaris microalgae to a 4 m3 pilot-plant photobioreactor is examined, compared to the performance of a 25 L automated laboratory bioreactor. Beyond the size and configuration, the main differences of the two bioreactors are the mode of operation, the illumination nature and depth, the temperature, and pH. Specifically, temperature and illumination are naturally varying from day to day and season to season into the pilot-plant photobioreactor that is set inside a greenhouse. The specific growth factor appears to be higher for microalgal cultivation in the laboratory bioreactor. It is also found that the growth kinetics is severely slowed down during the winter months. This is primarily due to the low temperatures and the poor illumination observed during winter.

The Mediterranean region is expected to present reduced availability of water resources due to climate change. This study aims to assess the potential hydrological responses to climate change in the Kastoria basin (Western Macedonia, Northern Greece) for the period 2019-2078. Climate projections from eight regional climate models from EURO-CORDEX were bias-adjusted using the linear scaling method. The bias-adjusted climate data were used to force the FeFLOW hydro-logical model to predict the discharge of the Kastoria aquifer towards lake Orestiada along with the projected groundwater level distribution. Precipitation (temperature) shows a tendency to decrease (increase) mainly in late spring to early autumn while increase (decrease) in the other sea-sons. Moreover, results indicate a significant increase in temperature and a slight decrease in precipitation towards 2078, while the predicted groundwater level of Kastoria aquifer will reduce slightly. However, the future hydrological behavior of the basin indicates a substantial reduction by approximately 15% of total water yield towards the end of the century.

Numerical simulation was conducted to assess the impact of dust emission on typical environmental sites in Jinan City. The CALPUFF model was applied to five simulation scenarios. The results showed that dust emission had a significant impact on air quality in Jinan. The impact of dust emission on the average concentration of PM10 at 15 monitoring sites was 19.8 μg/m3, accounting for 14.9% of the annual total. The impact of dust emission on the average concentration of PM2.5 was 5.2 μg/m3, accounting for 8.1% of the annual total. Adoption of yellow warning measures in the emission reduction scenarios had insignificant environmental effects due to unfavorable meteorological conditions. Compared with the baseline scenario, the average concentrations of PM10 and PM2.5 decreased by 13.6% and 1.9%, respectively. After adoption of orange and red warning measures, the impact of site dust emission on air quality at the monitoring site was reduced significantly. Significant environmental effects were achieved after all construction sites within a 2-km radius of the monitoring site were closed. Compared with the baseline scenario, the average concentrations of PM10 and PM2.5 were reduced by 45.5% and 42.3%, respectively. The results showed that under adverse meteorological conditions, higher-level warning measures should be undertaken to reduce the impact of site emissions on environmental quality. Considering the economic and social effects of emission reduction, temporary construction stoppage within 2 km of the monitoring site is a feasible plan that is in accordance with the goals of comprehensive environmental management.

The commercial imidacloprid (IMD) insecticide [1-(6-chloro-3-pyridinyl) methyl-4,5-dihydro-N-nitro-1H-imidazole-2-amine] is widely used for the enhancement of crop production, but the intensive use of this insecticide has caused serious environmental problems. This work presents an electrochemical process for the removal of this insecticide using galvanostatic electrolysis at modified tantalum surface by lead dioxide film anode (Ta(PbO2)) anode. The electrolytic process was monitored by chemical oxygen demand (COD). The influence of operating parameters, such as current density, initial concentration of IMD, temperature and initial pH value was investigated. The COD decay follows a pseudo first-order kinetic and the process was under mass transport control. COD removal reach 97% when using an apparent current density of 100 mA cm−2, initial COD of 953 mg L−1 and at 25 °C after 4.5 h electrolysis time.