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The soil phosphorus (P) cycle and P transformation are largely driven by the soil bacterial microbial community. However, little is known about the effects of dazomet (DZ) soil fumigation on soil P and soil microbial communities associated with P transformation. This research investigated P released from three farm soils as a result of DZ fumigation and changes in enzyme activity, gene abundance, and the encoding alkaline phosphatase PhoD microbial community. After DZ fumigation, we observed a briefly significant increase in the available P and the active P fractionation. The soil ALP activity, 16s rRNA abundance, and the phoD gene decreased significantly after DZ fumigation. The abundance and diversity of phoD-harboring microbes also decreased shortly after fumigation, increased significantly 14–28 days later, and then decreased again toward the end of the experimental period of 86 days. The shared OTUs between treatments became fewer with increasing time after fumigation. The changes in available P and the active P fractionation after DZ fumigation were significantly correlated with the abundance of the dominant phoD-harboring microbes. DZ fumigation promoted P mineralization in these farm soils and changed the composition of phoD-harboring microbial communities, which will benefit crops able to absorb and use P.

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Chemical fabrication of a nanocomposite structure for electrode materials to regulate the ion diffusion channels and charge transfer resistances and Faradaic active sites is a versatile strategy towards building a high-performance supercapacitor. Here, a new ternary flower-sphere-like nanocomposite MnO2-graphite (MG)/reduced graphene oxide (RGO) was designed using the RGO as a coating for the MG. MnO2-graphite (MnO2-4) was obtained by KMnO4 oxidizing the pretreated graphite in an acidic medium (pH = 4). The GO coating was finally reduced by the NaBH4 to prepare the ternary nanocomposite MG. The microstructures and pore sizes were investigated by x-ray diffraction, scanning electron microscopy, thermogravimetric analysis, and nitrogen adsorption/desorption. The electrochemical properties of MG were systematically investigated by the cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy in Na2SO4 solution. The MG as an electrode material for supercapacitor exhibits a specific capacitance of 478.2 and 454.6 F g−1 at a current density of 1.0 and 10.0 A g−1, respectively. In addition, the capacitance retention was 90% after 8,000 cycles. The ternary nanocomposite enhanced electrochemical performance originates from the specific flower-sphere-like morphology and coating architecture bringing higher specific surface area and lower charge transfer resistance (Rct).