Satellite images are commonly used for defining thermal urban environment and heat islands in urban areas. The objective of this study was to analyze and evaluate thermal environment of Uzundere-Erzurum using satellite images provided by the Landsat Thematic Mapper (TM) sensor on board Landsat 5 satellite. In respect to land use and urban surface features, spatial characterization of thermal urban environment was defined. In order to define the link between surface emissivity, land surface temperatures (LST), and urban surface characteristics more effectively, the CORINE Land Cover (CLC) database for Uzundere was also used. Based on the Landsat satellite images, different land cover categories are defined, and the alterations of heat islands are identified according to these categories. The minimum and maximum surface temperatures were obtained from open spaces, non-vegetated bare rocky areas (− 1.8 and 29.1 °C, respectively). The surface temperature in the water areas was much better (7.5 and 21.9 °C) and followed by green areas surface temperature (− 0.9 and 28 °C). Surface temperatures should be considered energy-focused planning.

This study investigated phytoplankton and bacterioplankton communities by flow cytometer in a tributary backwater area of the Three Gorges Reservoir, China. Samplings were conducted in two cyanobacterial bloom periods (May and August) and no algal-blooms period (November) of 2014, representing three different operational stages of the reservoir, i.e., reservoir discharge period, fluctuating period in the summer flood season, and high water level in the impoundment period. Phyto- and bacterioplankton exhibit a wide range of variability along the depth profiles of the water column. In the investigated two cyanobacterial bloom periods, prokaryotes accounted for over 50% of the total phytoplankton. As for bacterioplankton, low nucleic acid bacteria were dominant in August and November. A positive correlation was observed between phytoplankton (pico- and nanophytoplankton), Chl a, and bacterioplankton. High nucleic acid groups and prokaryotes were highly coupled in May and August, which indicated that this high nucleic acid group could probably contribute to the explanation of cyanobacterial bloom formation in this area.

A series of Nb-doped (Ce,Cr)ₓO₂-Nb₂O₅ mixed oxides with varying (Ce,Cr)ₓO₂/Nb₂O₅ mass ratio were prepared by a co-precipitation method and evaluated for the catalytic performance of eliminating 1,2-dichloroethane (DCE). The results indicate that there exists a strong synergistic effect between acid sites and redox species in (Ce,Cr)ₓO₂-Nb₂O₅ improving the catalytic activity for DCE oxidation. Appropriate Nb doping could promote the high dispersion and the interaction of metal oxides in the (Ce,Cr)ₓO₂-Nb₂O₅ catalysts, resulting in the formation of more Cr⁶⁺ species with strong oxidizing ability and excellent mobility of oxygen species from bulk to surface to create more active sites for DCE deep oxidation. The (Ce,Cr)ₓO₂-Nb₂O₅ catalysts with (Ce,Cr)ₓO₂/Nb₂O₅ ratios of 2/1~1/2 exhibit excellent catalytic activity and durability for DCE degradation in dry air as well as benzene or water vapor, and less chlorinated byproduct is produced during the degradation of DCE.

There is growing public concern about the global expansion of harmful algal bloom species (HABs), with dinoflagellate microalgae comprising the major portion of the harmful taxa. These motile, unicellular organisms have a lifecycle involving sexual reproduction and resting cyst formation whereby cysts can germinate from sediments and ‘seed’ planktonic populations. Thus, investigation of dinoflagellate cyst (dinocyst) distribution in sediments can provide significant insights into HAB dynamics and contribute to indices of habitat quality. Species composition and abundance of dinocysts in relation to sediment characteristics were studied at 18 stations in two densely populated temperate Australian estuaries, Sydney Harbour (Parramatta River/Port Jackson; PS) and Botany Bay (including Georges River; GB). Eighteen dinocyst taxa were identified, dominated by Protoceratium reticulatum and Gonyaulax sp.1 in the PS estuary, together with Archaeperidinium minutum and Gonyaulax sp.1 in the GB estuary. Cysts of Alexandrium catenella, which is one of the causative species of paralytic shellfish poisoning (PSP), were also detected in both estuaries. Out of the measured sediment characteristics (TOC, Cd, Cr, Cu, Fe, Pb, Mn, Ni, Zn and polycyclic aromatic hydrocarbons), TOC was the parameter explaining most of the variation in dinocyst assemblages and was positively correlated to most of the heavy metals. Given the significant relationship between sediment TOC and dinocyst abundance and heavy metal concentrations, this study suggests that sediment TOC could be broadly used in risk management for potential development of algal blooms and sediment contamination in these estuaries.

The extraction efficiency of heavy metals from soils using three forms of gamma poly-glutamic acid (γ-PGA) as the washing agents was investigated. Controlling factors including agent concentrations, extraction time, pH, and liquid to soil ratio were evaluated to determine the optimum operational conditions. The distribution of heavy metal species in soils before and after extraction processes was analyzed. Up to 46 and 74% of heavy metal removal efficiencies were achieved with one round and a sequential extraction process using H-bonding form of γ-PGA (200 mM) with washing time of 40 min, liquid to solid ratio of 10 to 1, and pH of 6. Major heavy metal removal mechanisms were (1) γ-PGA-promoted dissolution and (2) complexation of heavy metal with free carboxyl groups in γ-PGA, which resulted in heavy metal desorption from soils. Metal species on soils were redistributed after washing, and soils were remediated without destruction of soil structures and productivity.

Rice soil is a source of emission of two major greenhouse gases (methane (CH₄) and nitrous oxide (N₂O)) and a sink of carbon dioxide (CO₂). The effect of inorganic fertilizers in combination with various organics (cow dung, green manure (Sesbania aculeata) Azolla compost, rice husk) on CH₄ emission, global warming potential, and soil carbon storage along with crop productivity were studied at university farm under field conditions. The experiment was conducted in a randomized block design for 2 years in a monsoon rice (cv. Ranjit) ecosystem (June–November, 2014 and 2015). Combined application of inorganic (NPK) with Sesbania aculeata resulted in high global warming potential (GWP) of 887.4 kg CO₂ ha⁻¹ and low GWP of 540.6 kg CO₂ ha⁻¹ was recorded from inorganic fertilizer applied field. Irrespective of the type of organic amendments, flag leaf photosynthesis of the rice crop increased over NPK application (control). There was an increase in CH₄ emission from the organic amended fields compared to NPK alone. The combined application of NPK and Azolla compost was effective in the buildup of soil carbon (16.93 g kg⁻¹) and capacity of soil carbon storage (28.1 Mg C ha⁻¹) with high carbon efficiency ratio (16.9). Azolla compost application along with NPK recorded 15.66% higher CH₄ emission with 27.43% yield increment over control. Azolla compost application significantly enhanced carbon storage of soil and improved the yielding ability of grain (6.55 Mg ha⁻¹) over other treatments.

Fe₂O₃/graphite (Fe₂O₃/C) and nano-TiO₂-coated glass bead were prepared by impregnation and sol–gel method respectively and employed as the catalyst of a novel three-dimensional electrode photoelectrocatalytic (3-D PEC) system. The photoexcited electrons can transfer from TiO₂, Fe₂O₃ to counter electrode. It improves the migration of photoexcited charges, retards the fast recombination of electron–hole, and increases the lifetime of photogenerated holes (h⁺). In addition, the cycle reaction of Fe³⁺/Fe²⁺ on Fe₂O₃/C surface enhanced the Fenton reaction which can produce more hydroxyl radicals (·OH) and promote the capacity of mineralization of the pollutants. This novel 3-D PEC system showed excellent performance for the degradation of berberine chloride form (BCF). At the pH value of 3, 93% BCF was removed within 60 min; besides, 98.64% COD removal rate, 78.96% mineralization, 21.47% mineralization current efficiency, and just 3.16 kW h g⁻¹TOC energy cost were obtained in 120 min. In this study, we proposed the 3-D PEC mechanism. Electron spin resonance (ESR) and scavenging experiments suggest that the major reactive oxygen species (ROS) are superoxide radicals (O₂·⁻), ·OH, and h⁺, while the role of sulfate radical (SO₄·⁻) is insignificant. This work provides a new dimension for the design of reactors for wastewater treatment and the construction of the 3-D PEC system can potentially be utilized in water purification.

Basic oxygen furnace slags (BOS) are by-products of basic oxygen steel production. Whereas the solubility of some elements from these slags has been well investigated, information about the mineralogy and related leaching, i.e., availability of the environmentally relevant elements chromium (Cr), molybdenum (Mo), and vanadium (V), is still lacking. The aim of this study was to investigate these issues with a modified, four-fraction-based, sequential extraction procedure (F1–F4), combined with X-ray diffraction, of two BOS. Extractants with increasing strength were used (F1 demineralized water, F2 CH₃COOH + HCl, F3 Na₂EDTA + NH₂OH·HCl, and F4 HF + HNO₃ + H₂O₂), and after each fraction, X-ray diffraction was performed. The recovery of Cr was moderate (66.5%) for one BOS, but significantly better (100.2%) for the other one. High recoveries were achieved for the other elements (Mo, 100.8–107.9% and V, 112.6–87.0%), indicating that the sequential extraction procedure was reliable when adapted to BOS. The results showed that Cr and Mo primarily occurred in F4, representing rather immobile elements under natural conditions, which were strongly bound into/onto Fe minerals (srebrodolskite, magnetite, hematite, or wustite). In contrast, V was more mobile with proportional higher findings in F2 and F3, and the X-ray diffraction results reveal that V was not solely bound into Ca minerals (larnite, hatrurite, kirschsteinite, and calcite), but also bound to Fe minerals. The results indicated that the total amount of recovery was a poor indicator of the availability of elements and did not correspond to the leaching of elements from BOS.

Cholera is a global public health problem with high endemicity in many developing countries in Africa. In 2014, Ghana experienced its largest epidemic with more than 20,000 cases and 200 deaths; most of it occurred in the Accra Metropolitan Area (AMA). Ghana’s disease surveillance system is mainly clinically based and focused on case detection and management. Environmental exploration for the etiological agents is missing from the surveillance strategy. This study therefore assessed the occurrence of toxigenic Vibrio cholerae in water storage systems in selected high risk areas in the AMA area prior to the 2014 outbreak. Three hundred twenty water samples from 80 households’ water storage systems were analyzed for toxigenic Vibrio cholerae using the bacterial culture method. Presumptive V. cholerae was isolated from 83.8% of households’ water storage systems. The viable cells ranged from 1 to 1400 CFU/100 ml. Vibrio cholerae O1 serotype was isolated from five households in Old Fadama, one household in Shiabu, and one household in Bukom in the month of May and a similar trend was observed for the months of June and July. The presence of Vibro cholerae in the water storage vessels used for drinking confirms the need to consider environmental surveillance for toxigenic Vibro cholerae particularly in high-risk areas to strengthen the existing surveillance system.