博士課程3年のIdhaさんが主著の論文が、Estuarine, Coast and Shelf Sciences誌に掲載されました。有明海を対象に、微量元素（鉄、マンガン、銅、コバルト）の供給と除去過程を詳細に解析しました。おめでとうございます！
This paper discussed the variabilities of trace metals (dissolved Fe, Mn, Cu, and Co) in a semi-enclosed Bay (Ariake Sea) that reflects the combined effect of water circulation and geochemically driven cycles in shaping the distribution of those metals.
Figure 1. Map of Ariake Sea surrounding Kyushu Island, Japan. Orange dots represent sampling stations from the 2018 cruise in Ariake Sea and surrounding rivers. Green triangles represent the sampling stations from the 2015 cruise in Ariake Sea. Blue dots represent sampling stations in the East China Sea that were taken in 2019.
In the complex and high dynamic system of a coastal area like the Ariake Sea those trace metals behave differentially. While dissolved Fe and Mn (hereafter denoted as d-Fe and d-Mn, respectively) were removed during estuarine mixing, dissolved Cu (d-Cu) showed additional input via intra-estuarine processes. We proposed that sedimentary fluxes supplied more d-Cu than other possible sources such as photodissolution of suspended particulate matter, groundwater discharge, and atmospheric deposition. On the other hand, the balance between input and removal of d-Co leads to its conservative pattern.
Fig. 2 Relationship between salinity and [NO3-], [NO2-], [NH4+], DIN, [PO43-], [Si(OH)4], d-Fe, d-Mn, d-Cu, and d-Co from the 2018 cruise. The color dots and dashed lines represented the sampling station and the mixing line, respectively. For d-Fe and d-Mn, the insets showed all samples, while the larger graph provided expanded views for clarity.
-IYI-
