ABSTRACT
To gain a better understanding of the sources and ecological effects of plastic contamination in Lithuanian rivers, as well as to provide guidance for mitigation, monitoring is necessary. This is a logistically and financially demanding endeavor, particularly in the case of microplastics. Citizen science provides a viable option for sampling sites that are accessible, thus enabling the monitoring of wide areas. In Lithuania, a citizen science approach was employed, with schoolchildren examining litter at riversides and identifying potential sources at 24 sampling sites in Autumn 2022 and 32 in Spring 2023, covering both large and small rivers. The maximum amount of 220 items per location was registered in Autumn 2022, whereas 111 items per location were registered in Spring 2023. The two main types of microlitter discovered were plastic (34-42%) and cigarette butts (17-22%), with glass, paper, and metal also present, which suggests that recreational visitors are the main source of litter. By K-means clustering analysis, all locations were divided into four clusters according to litter composition. To sum up, the findings of this study illustrate the importance of citizen science in providing insight into the contamination of Lithuanian rivers, which can be used to inform the development of conservation strategies.
Subject(s)
Citizen Science , Lithuania , Plastics , Environmental Monitoring , Cluster AnalysisABSTRACT
In recent years, microplastics have become an integral part of the terrestrial and aquatic environments, which is one of the major concerns of communities around the world. Therefore, it is necessary to know the current status of studies and feasible potentials in the future. This study, conducted an in-depth bibliometric analysis of publications from 1990 to 2022 to present the influential countries, authors, institutes, papers, and journals on microplastics. Findings reveal that there has been a steady increase in microplastic publications and citations in recent years. And, the number of publications and citations has increased 19 and 35 times since 2015. Besides, we performed a comprehensive keyword analysis to show the significant keywords and clusters in this field. In particular, this study used the TF-IDF method as a text-mining analysis to extract the new keywords used in recent years (i.e., 2020-2022). New keywords can draw the attention of scholars to important issues and provide a basis for future research directions.
Subject(s)
Microplastics , Plastics , Bibliometrics , Data MiningABSTRACT
The effects of air pollution on the general public received much attention recently. Personal exposure and deposition fraction of aerosol particles were studied in Vilnius, Lithuania, focusing on individuals working in an office and driving to work. Aerosol monitoring in the urban background was found to give an indication of the minimum concentrations of particulate matter (PM) expected at urban roads, as these correspond to the lowest PM concentrations measured there. In March 2021, PM2.5 concentrations at the urban background monitoring station reached values above the annual limit of 5 µg/m3 the World Health Organization in 50% of cases. Our study shows significant differences in exposure to air pollution in a car cabin and in a modern office. According to the multiple-path particle dosimetry model, the exposure of the person in the office is about 14 times lower than driving a car, where the minute deposition dose for PM1 is 0.072 µg/min for the period when the PM2.5 concentration in the urban background reaches 10 µg/m³. Compared to the PM2.5 mass concentration at the urban background station, the mean PM2.5 concentration in the vehicle reaches values that are 2-3 times higher. During the working day, when driving takes less than 10% of the time considered (commuting plus working), PM exposure during driving accounts for about 80% of the PM exposure caused by PM concentration in the office.
ABSTRACT
Nowadays, the urban waste disposal and the proper location for doing so is considered as one of the most important urban service issues, which has the potential of causing environmental hazards for the citizens, if not done properly. One of the newest methods of waste burial is using plasma incinerator reactors. Using the advanced technology of plasma reactors in waste disposal has been the subject of study for a considerable number of researchers in the last few years. Moreover, insignificant emissions of environmental pollutants and high efficiency in these reactors have led to a high incentive for using them in the area of urban services. Therefore, finding the proper location for the plasma incinerator reactor in order to minimize environmental hazards is considered as a very important issue. In the present study, different parts of this reactor and its working procedure are presented at first. Then, quantitative and qualitative criteria effective on locating plasma incinerator reactor are presented, and these criteria are given proper weights using analytic hierarchy process (AHP) multi-criteria decision making method. Next, the data were collected for the studying area, and then, weighting, analysis, and presentation of geospatial data were performed using the geographic information system (GIS). Finally, the output map for installing location of the plasma incinerator reactor was developed in three classes of good, average, and bad.
