Many shorebird populations are in decline along the East Asian-Australasian Flyway. The rapid loss of coastal wetlands in the Yellow Sea, which provide critical stop-over sites during migration, is believed to be the cause of the alarming trends. The Yalu Jiang coastal wetland, a protected area in the north Yellow Sea, supports the largest known migratory staging populations of Bar-tailed Godwits Limosa lapponica (menzbieri and baueri subspecies) and Great Knots Calidris tenuirostris. Monitoring of the macrozoobenthos food for these shorebirds from 2011 to 2016 showed declines of over 99% in the densities of the bivalve Potamocorbula laevis, the major food here for both Bar-tailed Godwits and Great Knots. The loss of the bivalve might be caused by any combination of, but not limited to: (1) change in hydrological conditions and sediment composition due to nearby port construction, (2) run-off of agrochemicals from the extensive shoreline sea cucumber farms, and (3) parasitic infection. Surprisingly, the numbers of birds using the Yalu Jiang coastal wetland remained stable during the study period, except for the subspecies of Bar-tailed Godwit L. l. menzbieri, which exhibited a 91% decline in peak numbers. The lack of an overall decline in the number of bird days in Great Knots and in the peak numbers of L. l. baueri, also given the published simultaneous decreases in their annual survival, implies a lack of alternative habitats that birds could relocate to. This study highlights that food declines at staging sites could be an overlooked but important factor causing population declines of shorebirds along the Flyway. Maintaining the quality of protected staging sites is as important in shorebird conservation as is the safeguarding of staging sites from land claim. Meanwhile, it calls for immediate action to restore the food base for these beleaguered migrant shorebirds at Yalu Jiang coastal wetland.

In this work, the selective removal of ions from multicomponent mixtures using functionalized magnetic nanoparticles (FMNPs) was demonstrated. As, Sb, and Se ions were efficiently removed from complex mixtures, such as Rhodiola rosea extracts and influent water from the sewage treatment unit of a beer brewery. As, Sb, and Se ions could be selectively adsorbed by FMNP, as demonstrated by the inductively coupled plasma mass spectrometer analyses. We also demonstrated that Pb ions are weakly adsorbed, whereas Cu, Cd, and Zn ions cannot be adsorbed by FMNP. The complexity of the mixture did not affect the selective removal of As, Sb, and Se ions. FMNP could be recycled and used repeatedly. Magnetic separation could then be applied for the selective separation of complex mixtures, such as plant extracts, industrial wastewater, and tap water.

Dense lossy AlN–SiC composites doped with Y2O3 were fabricated by spark plasma sintering (SPS). Both the microstructure and the dielectric properties are different from those of hot-pressed samples. Microstructure analysis reveals little solid solution (AlN)x(SiC)1-x is formed. Scanning evanescent microwave microscopy images show that the materials by SPS exhibit large contrast in dielectric permittivity, whereas the hot-pressed materials show very mild fluctuation in dielectric permittivity over the samples. The results indicate that AlN–SiC composites fabricated by SPS can be treated approximately as a mechanical mixture of AlN and SiC when estimating complex permittivity of the composite in the microwave range. The complex permittivity of the composites with different SiC contents can be phenomenologically predicted by effective medium approximation.