Efforts to reduce the toxic effects of microplastics (MPs) on the environment have increased globally in recent years. However, the existing models used for the simulation of contaminant transport in groundwater are meant for dissolved substances, which is not suitable for studying MPs. Therefore, in this study, the transport of MPs in a saturated porous medium was modeled by establishing governing equations. Simulations were performed using the finite element method to examine the effects of the parameters of the governing equations on the transport of MPs. The results suggest that it is necessary to reduce the diffusivity of MPs and increase the water flow velocity, porosity, and first-order attachment coefficient to effectively contain this environmental hazard. From the simulation results, it can be derived that a combination of low diffusivity, fast water flow velocity, and high soil porosity may reduce the amount of MPs that are leaked into groundwater environments. The modeling and simulations performed in this study provide a clear understanding of the transport phenomena of MPs with applications in combating water pollution.

The skyrocketing single-plastic demand during the coronavirus disease 2019 (COVID-19) pandemic proved the limitation of top-down environmental policies in accomplishing sustainable consumption and waste management. Nevertheless, ‘smart consumers’ can make smart choices for sustainable development. However, a review of the South Korean environmental education curriculum reveals that the current structure heavily leans towards the elementary level and does not enlighten the public on ‘what’ and ‘how’ to live sustainably. This study uses a quick survey to suggest that the effectiveness of environmental education may be enhanced if: (1) guidance on how to live with the natural environment in harmony for collective cooperation towards resilient and sustainable community building is incorporated with a clear purpose, (2) environment-friendly culture-building activities are enforced to institutionalise a new paradigm of sustainability to replace today’s consumerism, and (3) contents are updated regularly to include Earth and environmental science knowledge in the state of art.

본 연구에서는 강원도 삼척시 카르스트 지역의 하천수와 지하수의 수화학적 진화에 대하여 평가하였다. 연구지역의 하천수와 지하수는 높은 농도의 칼슘과 중탄산이온 농도를 보였는데 이는 주로 탄산염암 중 석회암의 용해에 의한 결과이다. 탄소동위원소와 이온비에 의하면 이 지역의 수화학은 주로 탄산염암 용해 그리고 일부대기 중 이산화탄소 용해에 영향을 받음을 지시하였다. 특별히 바다 근처의 하천수는 높은 농도의 나트륨과 염소이온 농도를 보였다. 산소 및 수소 안정동위원소의 조성과 나트륨과 염소이온의 이온비를 살펴보면 이 지역의 하천수는 전형적인 편서풍에 의한 서해안 해수증발에서 유래한 것보다는 인근 동해안 해수의 증발에 기원임을 지시하였다.

This study analyzed the hydrochemical characteristics and microbial communities of karst water in Samcheok, Korea, and compared water quality results to identify the seasonal characteristics and hydrogeological connectivity of the study areas of Hamaengbang-ri, Gyogok-ri, Yeosam-ri, and the downtown area of Samcheok. Field survey and water quality analysis were performed in July 2019, February 2020, and April 2020. Hydrochemical analysis of karst water (groundwater and surface water) showed that most samples were comprised of Ca-HCO₃ and that water–rock interactions were a dominant factor compared to precipitation and evaporation (crystallization). For seasonal characteristics, water–rock interactions appeared more active in the dry season than in the rainy season. Calcite weathering was dominant in the dry season, whereas dolomite weathering dominated the rainy season. Moreover, the saturation indexes for the dry and rainy seasons were less than and greater than 0, respectively, corresponding to an unsaturation (oversaturation) state; thus, white precipitate distributed in the study areas was deposited in the rainy season. Finally, as a result of analyzing the hydraulic characteristics between regions, hydrogeological similarities were identified between Hamaengbang-ri and Yeosam-ri, and between Gyogok-ri and downtown Samcheok, which suggested hydrogeological connectivity between each of the pairs.

Soil has multiple functions, including the provision of habitat to organisms, and most biological activities occur in the surface soil. Due to the negative effects of soil erosion, efforts for soil conservation are being made, including the development of a reliable index that can help assess soil quality. In this study, the physical and chemical properties and biological genes from grassland topsoil were analyzed, in order to identify surface soil organism markers that could be used as a soil quality index. Six spots of grassland topsoil were analyzed, one high-quality and five low-quality, based on a web-based soil quality assessment module. Consequently, eukaryotes and prokaryotes with different soil quality ratios were compared and examined. The following bacteria and archaea have the potential to be used in soil quality assessment: circulation of materials including nitrogen, Nitrospira spp., Candidatus Nitrososphaera, and Candidatus Nitrosotalea; biological purification, Geobacter spp.; pathogens, Burkholderia spp., Paraburkholderia spp., Pseudomonas brassicacearum, and Rhizobacter spp.; antibiotic secretion, Candidatus Udaeobacter; and material degradation Steroidobacter spp. and Rhodanobacter spp. This study provides primary data for identifying biological markers for soil quality evaluation. In the future, a wider variety of data need to be accumulated to develop a highly reliable index related to soil quality.

The water spider (Argyroneta aquatic) is the only known spider to live a fully aquatic life. Therefore, it has been the subject of a series of studies on various aspects of its unique biology such as its reproductive behavior, sexual dimorphism, physiology, genetics, and silk. However, there have been relatively few studies on the hydroecology of where water spiders live. The water spider habitat in Eundae-ri, Yeoncheon is the only habitat for A. aquatica, a globally rare species, in South Korea. In this region, the water level of the wetland is automatically adjusted to groundwater owing to continued drying. Here, the surface water, wetland, and groundwater near the A. aquatica habitat were studied using hydrochemical, microbiological, and correlation analyses. The hydrochemical properties—water temperature, pH, electrical conductivity, dissolved oxygen (DO), oxidation reduction potential, and turbidity—of the surface water and wetland were similar. The Piper diagrams revealed that the wetlands, surface water, and most of the groundwater portrayed Ca-HCO₃-type properties, whereas only areas where the water level of the wetland was controlled displayed Na-HCO₃-type properties. Furthermore, the NO₃ content was too low to be detected in the wetland, indicating clean and non-polluted water conditions; additionally, heavier oxygen-hydrogen isotopes were observed because these regions were climatically affected by the wetland. The dominant bacteria were Proteobacteria, Actinobacteria, Bacteroidetes, Cyanobacteria, Verrucomicrobia, and Nitrospirae. The correlation analysis revealed that the major environmental control factors of the A. aquatica habitat were DO, temperature, and pH, and the related bacteria were Cyanobacteria, Actinobacteria, and Verrucomicrobia.