本文研究了NaCl、Na₂SO₄、Na₃PO₄ 3种背景电解质对牛粪生物质炭中腐殖酸吸附和解吸的影响。结果表明：在这3种背景电解质作用下，牛粪生物质炭对腐殖酸的吸附量和吸附率随着加入液腐殖酸浓度的增加而增加，但是增加速度逐渐变缓。3种背景电解质相比，NaCl中牛粪生物质炭对腐殖酸的吸附量和吸附率均为最高，吸附量范围为0.13 ~ 6.10 mg/g，吸附率范围为25.40% ~ 87.14%。随着加入液腐殖酸浓度的增加，吸附态腐殖酸的解吸量逐渐增加，解吸率逐渐减小。3种背景电解质相比，Na₂SO₄中牛粪生物质炭吸附的腐殖酸的解吸量最高，解吸量范围为0.15 ~ 0.78 mg/g。加入液腐殖酸浓度为140 mg/L，3种背景电解质中牛粪生物质炭吸附的腐殖酸的解吸量均达到最大值，解吸量的大小顺序为Na₂SO₄>Na₃PO₄>NaCl。Na₃PO₄对腐殖酸的解吸率影响最大，解吸率范围为17.24% ~ 90.55%，NaCl对腐殖酸的解吸率影响最小，解吸率范围为8.22% ~ 53.54%。用Langmuir拟合3种背景电解质中腐殖酸的等温吸附曲线和等温解吸曲线，其相关系数都达到显著水平。研究结果揭示了不同背景电解质对牛粪生物质炭吸附和解吸腐殖酸的影响，可为土壤保土保肥提供理论参考。

The effects of three kinds of background electrolytes (NaCl, Na₂SO₄ and Na₃PO₄) on the adsorption and desorption of humic acid in the dairy manure biochar were studied. Results showed that under the effect of the three kinds of background electrolytes, the dairy manure biochar adsorption capacity and adsorption rate increased with the increase of liquid humic acid concentration, however, the increasing speed gradually slowed down. Compared to the three kinds of background electrolytes, NaCl had the highest adsorption capacity and adsorption rate of humic acid in dairy manure biochar, The range of adsorption capacity was 0.13–6.10 mg/g, the range of adsorption rate was 25.40%–87.14%. With the increase of the concentration of adding liquid humic acid, the desorption capacity of adsorption state humic acid gradually increased, and the desorption rate gradually decreased. Compared to the three kinds of background electrolytes, Na₂SO₄ had the highest desorption rate of adsorptive humic acid in dairy manure biochar, and the range of desorption capacity was 0.15–0.78 mg/g. the concentration of liquid humic acid was 140 mg/L, the desorption capacity of the three kinds of background electrolytes to the adsorptive humic acid of dairy manure biochar have reached the maximum value, the order of desorption capacity was Na₂SO₄ >Na3PO4>NaCl. Na₃PO₄ had the greatest effect in the desorption rate of humic acid, the range of desorption rate was 17.24%–90.55%, NaCl had the minimal effect in the desorption rate of humic acid, the range of desorption rate was 8.22%–53.54%. The isothermal adsorption curves and isothermal desorption curves of the three kinds of background electrolytes in humic acid were fitted with Langmuir, and the correlation coefficients were significant. The results showed that the effects of different background electrolytes to dairy manure biochar on the adsorption and desorption of humic acid were studied, which provided a theoretical reference for soil fertility and soil fertility.

S157.1；S157.2；S157.3

国家自然科学基金项目(41461061)资助。