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While biochar amendment is widely recommended as an excellent agricultural management practice, the biochar effect on the productivity of legume crops with symbiotic microorganisms has been poorly elucidated. Hence, a pot experiment was conducted by growing soybean with or without commercial rhizobia inoculation in an arbuscular mycorrhizal (AM) fungi rich sandy soil amended with wheat straw biochar produced respectively at 350 °C, 450 °C, and 550 °C. We tested the effect of biochar on soybean–rhizobia symbiosis and its impact on plant growth, leaf gas exchange and mycorrhizal colonisation. In brief, rhizobia inoculation, without biochar, increased net photosynthetic rate by 81% and plant total biomass by 44% compared to no inoculation (the control). Without inoculation, amendment of low-temperature biochar (350 ºC) resulted in higher (by 51%) plant biomass than high-temperature (550 °C) biochar. With rhizobia inoculation, low-temperature biochar decreased plant biomass by 9.3% compared to high-temperature biochar. Further, soybean with rhizobia under high-temperature biochar decreased plant biomass by 17% compared to rhizobia inoculation only but increased by 19% compared to the control. Soybean leaf gas exchange capacity and root morphological traits were consistent with plant biomass but symbiotic activity showed small differences among all the treatments. Overall, N-fixing rhizobia could alter the biochar effect on soybean in soil rich in indigenous AM fungi, depending on the pyrolysis temperature of the biochar used. Low-temperature biochar stimulated soybean growth greater than high-temperature biochar, while rhizobia shifted biochar's positive effect. • Pyrolysis temperature shaped biochar effect on soybean growth with and without rhizobia inoculation in a sandy soil. • Soybean growth without rhizobia inoculation is promoted rather by biochar-350 °C than by biochar-550 °C. • A tradeoff on soybean plant growth between biochar and rhizobia inoculation. • Soil inorganic N correlated with root morphology while leaf gas exchange responded to soil NO 3 -. [ABSTRACT FROM AUTHOR]

Highlights: [•] CMC-Li that was suitable for application in the battery was synthesized for the first time. [•] Three new composite nanometer fiber CMC-Li, AQ/CMC-Li, AQ/CNF/Li models by electrospinning for the first time. [•] Explained the advantages that using CMC-Li coated AQ as an anode of the battery by electrospinning for the first time. [•] Performance of battery with CMC-Li with the high DS was superior to that with low DS. [•] Nano CNF/Li has become a kind of new material that can improve the electrode performance by electrospinning. [ABSTRACT FROM AUTHOR]

Biochar-based compound fertilizers (BCF) and amendments have proven to enhance crop yields and modify soil properties (pH, nutrients, organic matter, structure etc.) and are now in commercial production in China. While there is a good understanding of the changes in soil properties following biochar addition, the interactions within the rhizosphere remain largely unstudied, with benefits to yield observed beyond the changes in soil properties alone. We investigated the rhizosphere interactions following the addition of an activated wheat straw BCF at an application rates of 0.25% (g·g−1 soil), which could potentially explain the increase of plant biomass (by 67%), herbage N (by 40%) and P (by 46%) uptake in the rice plants grown in the BCF-treated soil, compared to the rice plants grown in the soil with conventional fertilizer alone. Examination of the roots revealed that micron and submicron-sized biochar were embedded in the plaque layer. BCF increased soil Eh by 85 mV and increased the potential difference between the rhizosphere soil and the root membrane by 65 mV. This increased potential difference lowered the free energy required for root nutrient accumulation, potentially explaining greater plant nutrient content and biomass. We also demonstrate an increased abundance of plant-growth promoting bacteria and fungi in the rhizosphere. We suggest that the redox properties of the biochar cause major changes in electron status of rhizosphere soils that drive the observed agronomic benefits. Unlabelled Image • Biochar-based fertilizer (BCF) is known to enhance crop yields and soil properties. • Wheat straw BCF was applied to the soil to investigate rhizosphere interactions. • There was an increase in rice yield, and N (40%), P (46%), Mg, K and Na uptakes. • Micron and submicron-sized biochar were embedded in the plaque layer. • Biochar increased soil Eh, which resulted in greater plant nutrient content. [ABSTRACT FROM AUTHOR]