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The application of potassium fertilizer by farmers is often not appropriate and causing environmental pollution. By understanding the adsorptive characteristics of potassium (K) on different soils, we can prevent excessive application of K‐fertilizer that can cause environmental impact. The Gapon exchange coefficient (KG), for exchange between K and Ca, was considered as an important factor influencing the adsorption of K. This study was conducted to compare the constant KG of five important farm soils in Taiwan. The KG and CEC were then used to predict K buffering capacity (PBC). Finally, the relationship between exchangeable K ratio (EP) and K adsorption ratio (PAR) was examined. The results show that five soils have same trends, indicating that KG decreases with increase in K saturation. The CEC and KG of Liuying (Ly) soil are both high, so that their K buffering capacity is high. The KG and CEC of Chanjing (Cj) and Sanhua (Sh) soil show moderate values. The CEC of Erling (El) soil is high, but its KG is low, so that its K buffering capacity is moderate. On the other hand, the KG of Newniaokang (Nnk) soil is high but its CEC is low, so its K buffering capacity is also moderate. The correlations between EP and PAR of five soil show linear relationship at three treatments of CaCl2 concentration. This study may provide an important clue to the fertilization management of K‐fertilizer on the different soil properties in Taiwan.

Massilia sp. strain Mn16-1_5 was isolated from serpentine soil. This strain is able to oxidize manganese and has the potential for bioremediation of chromium. Here, we present a 5.53-Mb draft genome sequence of this strain with a G+C content of 64.8% that might provide more information for species delineation and oxidase genes in this strain.

Phytoremediation is an economical and viable method for reducing cadmium (Cd) in polluted soils. Cd is transported from the roots to the stem. Binding of Cd by organic acids and amino acids and its subsequent transportation through plants via xylem vessels is verified. However, the roles that proteins play in Cd transport are still unclear. Rapeseed plants are selected for this study. After treating with Cd (0, 10, and 30 μmol L−1 (µM)), the proteins of the plant are analyzed using two‐dimensional electrophoresis. Twelve significantly differentially regulated spots are identified using mass spectrometry when the Cd concentration is increased; six of these spots are upregulated and six are downregulated. By identifying the functions of these proteins, transport of Cd to the xylem of rapeseed plants can be classified according to the cellular physiologies involved in carbohydrate metabolism, energy production, and redox damage reduction. This study provides a crucial basis for further proteomic and genetic studies on environmental Cd phytoremediation.

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