김륜미 Ryunmi Kim , 박선진 Sun-jin Park , 공동수 Dongsoo Kong

DOI:10.15681/KSWE.2024.40.6.279 Vol.40(No.6) 279-293, 2024

Distribution characteristics of four species (Hydropsyche kozhantschikovi, H. orientalis, H. valvata, H. formosana) of the caddisfly genus Hydropsyche (Trichoptera: Hydropsychidae) along with altitudinal gradient were analyzed with Probability Distribution Models (Exponential, Normal, Lognormal, Logistic, Weibull, Gamma, Beta, Gumbel) based on data collected from 25,370 sampling units of 3,695 sites from 2010 to 2021 in Korea. Inverted Weibull distribution model showed the best-fit for negatively skewed H. kozhantschikovi and H. orientalis and positively skewed H. valvata. Gamma distribution model showed the best-fit for positively skewed H. formosana. H. kozhantschikovi was distributed at an altitude range of 1 m to 849 m. H. orientalis was distributed at 1 m ~ 871 m. H. valvata was distributed at 3 m to 849 m and H. formosana was distributed at 12 m to 626 m. Altitudinal habitat suitability range was estimated to be 242 m to 574 m for H. kozhantschikovi, 500 m to 793 m for H. orientalis, 174 m to 485 m for H. valvata, and 137 m to 272 m for H. formosana. Results of altitudinal spectrum of suitability and altitude-related temperature revealed that H. formosana was thermophilic, H. kozhantschikovi and H. valvata were mesophilic, and H. orientalis was thermophobic. This is the first national-scale evaluation on altitudinal distribution of Hydropsyche in Korea. Results will be available in a further research study on altitudinal shift in species of Hydropsyche under climate change in the future.

Altitudinal distribution, Habitat suitability index, Hydropsyche, Thermality

박보현 Bohyeon Park , Thi Huyen Duong , 탁지현 Jihyeon Tak , 맹승규 Sung Kyu Maeng , 최수훈 Soohoon Choi

DOI:10.15681/KSWE.2024.40.6.294 Vol.40(No.6) 294-304, 2024

This study characterized the flow of particulate material and organic material in the pipeline used in a distribution system of a semiconductor ultrapure water production process. Polyvinylidene fluoride (PVDF) pipes were used in this study. They were filled with ultrapure water to measure the flow of particulate and organic material under static conditions. For a dynamic test, a pilot plant was built and tested for particulate and organic materials. The dynamic test was conducted twice with a minimum velocity of 0.91 m/s and a maximum velocity of 2.13 m/s according to American Society for Testing and Materials (ASTM) standards. Particulate and organic substances flowed out according to the change of velocity. Particulate material was measured using a nanoparticle tracking analyzer (NTA) and organic material was measured using total organic carbon (TOC). Results of both static and dynamic experiments showed similar trends in particulate and organic fluxes. In the case of dynamic experiments, particulate and organic material fluxes increased as the velocity increased while sizes of flushed particles decreased. Results of this study suggest that it is possible to estimate the particulate material outflow as the velocity changes during ultrapure water plant operation.

Nanoparticle tracking analyzer, Organic material, Particulate material, PVDF Pipeline, Ultrapure water

권대률 Kwon Daeryul , 박채홍 Park Chae Hong , 조현진 Cho Hyun Jin , 박미례 Park Mirye , 이상득 Lee Sang Deuk

DOI:10.15681/KSWE.2024.40.6.305 Vol.40(No.6) 305-315, 2024

The importance of evaluating phytoplankton composition, abundance, and biomass has been emphasized through the European Union’s Water Framework Directive (WFD). Accurate biomass estimation is a critical step in assessing the ecological status of aquatic ecosystems. While some European assessment systems propose that chlorophyll-a (Chl-a) can be used as a proxy for biomass, others recommend direct analysis of total biomass based on cell biovolume. Despite ongoing global research on the conversion of cell volume to carbon, Korea continues to use an outdated carbon conversion formula for algae published in 1985 without clear guidelines for modern applications. This study aimed to enhance the accuracy of estimating cell volume and carbon content of diatoms found in sediment cores from the Upo Wetland by modifying and rearranging geometric shapes for improved calculations. Referring to several European guidelines, we applied geometric shapes and formulas to classify 80 diatom species from Upo Wetland and calculated their biomasses accordingly. We then applied a carbon conversion formula to estimate organic carbon contents of these diatoms. Total carbon (C) content for the 80 diatom species from the Upo Wetland sediment was estimated to be 14,099 pg per cell. These findings are expected to provide valuable data for future assessments of microalgal carbon storage and sequestration rates. Additionally, this research contributes to the establishment of more accurate carbon conversion methodologies in Korea. It could be instrumental for studies focusing on microalgae-based carbon sequestration as part of climate change mitigation strategies.

Biomass, Biovolume, Freshwater diatoms, Organic carbon content

이승원 Seungwon Lee , 박지혜 Jihye Park , 조민기 Minkee Cho , 송민수 Minsu Song , 전준범 Junbeom Jeon , 배효관 Hyokwan Bae

DOI:10.15681/KSWE.2024.40.6.316 Vol.40(No.6) 317-337, 2024

The anaerobic ammonium oxidation (anammox) process has been demonstrated to increase nitrogen removal efficiency and settleability by incorporating iron particles. This study investigated the changes in microbial community structure of the anammox process due to the incorporation of iron particles. Anammox granules (AGs) and iron particle-integrated anammox granules (IP-IAGs) were developed using synthetic wastewater. Then, the real wastewater was applied to partial nitritation and IP-IAGs. The 16S rRNA gene amplicon sequencing revealed that dominant community members were different between each reactor. The dominant anammox genera in IP-IAGs were Ca. Brocadia and Ca. Jettenia. Planctomycetota, Pseudomonadota, Chloroflexi, and Bacteroidota phyla were commonly dominant in AGs and IP-IAGs. However, their relative abundances were changed before and after the iron particles were integrated. In addition, the alpha diversity and evenness of IP-IAGs were higher than AGs, confirming that the bacteria community was more diverse. The dominant anammox bacteria in previous studies were surveyed to explain the characteristics of the anammox community of this study. In addition, this study provides the sequences of suitable primers for quantifying anammox bacteria for the further investigation on the anammox community in iron particle-applied conditions.

Anaerobic ammonium oxidation, Bacterial community structure, Iron particle integrated anammox granule, Nitrogen removal