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Corbicula has often been reported as one of the most invasive freshwater species in the world. It plays an important role in the food chains of brackish water zones in Korea, where it is predominant. However, detailed information on the Corbicula diet is still lacking. The purpose of this study was to identify the potential prey of Corbicula fluminea in the Seomjin River using a DNA metabarcoding approach, as very little is known about its feeding selectivity in natural conditions. A survey was conducted at two study sites (1 and 2) in the Seomjin River in November 2021. The two sites were selected based on increasing salinity gradient. The dominant operational taxonomic unit in the pseudofeces and gut content of C. fluminea was Microcyclops varicans (Copepoda) and Oncorhynchus mykiss (Fish), respectively. The alpha diversity at site 1 was higher than that at site 2. More diverse potential prey species were identified at the site with low salinity (i.e., site 1). The utilization of this method is strongly recommended for determining specific predator–prey relationships in complex estuarine ecosystem. [ABSTRACT FROM AUTHOR]

The rapid increase in dam construction has resulted in a worldwide loss of natural river flows. Regulated dam discharge into estuaries can interrupt the spatiotemporal occurrence of brackish communities adapted to optimal salinity ranges, further threatening biodiversity and ecosystem function in the affected regions. We used annual survey records from the Nakdong River Estuary from 2009 to 2018 to identify the indirect effect of regulated dam discharge on plants and migratory waterfowl. Increased mean salinity during the spring season negatively influenced the area covered by plants and the number of days on which swans were present during winter. Moreover, the mean salinity during the early growing periods of plants providing food to waterfowl was regulated by the amount of freshwater discharge from the estuarine barrage rather than by the direct effect of precipitation. Conservation managers should consider the amount of dam discharge and the salinity conditions during spring to maintain sufficient food resources and supporting functions for migratory waterfowl in the estuary. Our study highlights the need for a comprehensive assessment of time‐lag effects to minimize the negative impacts resulting from regulated dam discharge. [ABSTRACT FROM AUTHOR]

Abstract: A mixed cathode material between Li2MnO3 and Li[Mn1/3Ni1/3Co1/3]O2 for high capacity lithium secondary batteries was introduced in this study. It was prepared using the sucrose combustion process because this is a simple process. The oxidation states of Mn, Co and Ni ions in the pristine Li[Li(1−x)/3Mn(2−x)/3Ni x/3Co x/3]O2 compounds were confirmed to be tetravalent, trivalent and divalent, respectively, via XANES measurements. Electrochemical charge/discharge studies showed that the highest first discharge capacity of 224mAh/g was obtained in composition of x =0.5 at a 0.2C rate. The oxidation state of the Co and Ni ions in the Li[Li1/6Mn1/2Ni1/6Co1/6]O2 changed to higher oxidation states, but that of the Mn ions did not change. [Copyright &y& Elsevier]

Recently, there have been many reports on efforts to improve the rate capability and discharge capacity of lithium secondary batteries in order to facilitate their use for hybrid electric vehicles and electric power tools. In the present work, we present a ZrO2-coated Li[Li1/6Mn1/2Co1/6Ni1/6]O2. The bare Li[Li1/6Mn1/2Co1/6Ni1/6]O2 shows a high initial discharge capacity of 224 mAh g−1 at a 0.2 C rate. Owing to the stability of ZrO2, it was possible to enhance the rate capability and cyclability. After 1 wt% ZrO2 coating, the ZrO2-coated Li[Li1/6Mn1/2Co1/6Ni1/6]O2 showed a high discharge capacity of 115 mAh g−1 after 50 cycles under a 6 C rate, whereas the bare Li[Li1/6Mn1/2Co1/6Ni1/6]O2 showed a discharge capacity of only 40 mAh g−1 and very poor cyclability under the same conditions. Based on results of XRD and EIS measurements, it was found that the ZrO2 suppressed impedance growth at the interface between the electrodes and electrolyte and prevented collapse of the layered hexagonal structure. [ABSTRACT FROM AUTHOR]

Background: Phragmites australis is a common foundation species found in inland and brackish estuarine ecosystems. P. australis stands provide a wide range of habitats for wetland organisms and perform essential functions, such as nutrient cycling, pollutant filtration, wave energy reduction, and soil stabilization. However, excessive growth of P. australis can degrade the quality of wetland habitats, thereby reducing the functions of restored wetlands., Methods: In this study, we investigated the effectiveness of vegetation management techniques, such as aboveground cutting and temporal inundation with varying depth and periodicity, in controlling the growth performance of P. australis and adjacent vegetation, Bolboschoenus planiculmis . Differences in growth responses to manipulated inundation stress between P. australis and B. planiculmis were measured., Results: Inundation stress of 10-50 cm caused significantly greater inhibition of growth performance in B. planiculmis compared to P. australis . The combination of aboveground-cutting and inundation treatments resulted in a significant inhibitory effect on the growth performance and survival rate of P. australis . The growth performance of P. australis , including stem volume and biomass, decreased and its mortality rate increased. Our manipulated experiment suggests a combined treatment approach of moderate inundation, such as 5-10 cm for 20-30 days, and aboveground cutting to manage the overgrowth of P. australis in restored brackish wetlands., Competing Interests: The authors declare that they have no competing interests., (© 2024 Park et al.)