Raw data of saltwater intrusion weakens Fe-(oxyhydr)oxide-mediated (im)mobilization of Ni and Zn in redox-fluctuating soil–groundwater system.xlsx

Fig. 1. Comparison of the dynamics of Eh (a) and the release of Ni (b), Zn (c), and Fe (d) in DWS (control experiment), PWS (without saltwater intrusion), BWS (with low-salinity intrusion), and SWS (with high-salinity intrusion) during the RED-REOX process. 

Fig. 2. Principal coordinate analysis (PCoA) with Jaccard dissimilarity of the microbial community in the soil at RED-20 (a). Relative abundance of the top 20 bacterial genera in the soil microbial communities at RED-20 (b).

Fig. 3. Comparison of the species transformation of F1-Ni (a), F2-Ni (b), F1-Zn (c), F2-Zn (d) in DWS (control experiment), PWS (without saltwater intrusion), BWS (with low-salinity intrusion), and SWS (with high-salinity intrusion) during the RED-REOX process. The line and “+” within the box represent the median and mean values of all data. The bottom and top edges of the box represent 25% (lower quartile) and 75% (upper quartile) of all data, respectively. The bottom and top bars represent minimal and maximal values, respectively. *P<0.05, **P<0.01, and ***P<0.001; ns = no significant difference; paired t-test was performed for RED (n=12) versus REOX (n=8). F1 is the weak acid-extractable fraction, and F2 is the reducible fraction. 

Fig. 4. Dynamics of Feo/Fed ratio (a), and the difference of Feo/Fed ratio (b) in DWS (control experiment), PWS (without saltwater intrusion), BWS (with low-salinity intrusion), and SWS (with high-salinity intrusion) during the RED-REOX process. The line and “+” within the box represent the median and mean values of all data. The bottom and top edges of the box represent 25% (lower quartile) and 75% (upper quartile) of all data, respectively. The bottom and top bars represent minimal and maximal values, respectively. *P<0.05, **P<0.01, and ***P<0.001; ns = no significant difference; paired t-test was performed for RED (n=12) versus REOX (n=8). Feo/Fed is the ratio of poorly crystalline iron oxide (Feo) to crystalline iron oxide (Fed).

Fig. 5. Species distribution of Ni (a) and Zn (b) as obtained by the linear combination fitting analysis of Ni K-edge XANES and Zn K-edge XANES spectra in the Ni and Zn hotspots. Schematic diagrams of Ni/Zn species transformation driven by PW (c). Schematic diagrams of Ni/Zn species transformation driven by SW intrusion (d).