【摘 要】
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Considerable research efforts have been devoted to increase phosphorus (P) availability dur-ing aerobic composting.However,there is little discussion weather the dissolved organic carbon (DOC) controls the transformation among P-fractions.Thus,we investig
【机 构】
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Key Laboratory of Wetland Ecology and Environment,Northeast Institute of Geography and Agroecology,C
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Considerable research efforts have been devoted to increase phosphorus (P) availability dur-ing aerobic composting.However,there is little discussion weather the dissolved organic carbon (DOC) controls the transformation among P-fractions.Thus,we investigated the changes in DOC compositions and P-fractions during biochar-amended composting (wet weight basis,5％ and 10％).TP content continuously increased since the \'concentration ef-fect\'during aerobic composting.NaHCO3-Pi,NaOH-Pi and HCl-Pi were main P-fractions,and biochar can improve P-bioavailability by transforming NaOH-Pi and HCl-Pi into NaHCO3-Pi.Structure equation models (SEMs) indicated that biochar enhanced the P-bioavailability through regulating the decomposition of DOC.Our results at least hint that the activation mechanism on P under the influence of DOC during biochar-amended composting.
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