Application of alkaline biochar has been proposed as an alternative to lime for remediation of acidic soils. However, questions remain as to how the reactions and fate of metals in acidic soils can be affected by biochar amendment. To find out how biochar addition might affect sorption-desorption behavior of zinc (Zn) in acidic soils, a soil with an initial pH value of 4.67 was treated with different levels [0 (control), 1%, 3%, and 6%] of biochar produced from pyrolysis of sugarcane bagasse at 600°C and incubated for 30 days under 80% of water holding capacity. At the end of the incubation period, important soil chemical properties were measured and batch isotherm experiments were performed to determine soil Zn sorption-desorption parameters. The results showed that the biochar-amended soils had higher pH values (up to 2.5 pH units), electrical conductivity (up to 2.66 times), and cation exchange capacities (up to 42%) relative to the un-amended acidic soil. Biochar addition also led to significant enhancements in soil exchangeable calcium, magnesium, sodium, and potassium cations. Both sorption and desorption isotherm experiments revealed the significantly higher capacity of the biochar-amended soils to retain Zn than that of the control. Moreover, the biochar-amended soils exhibited a higher affinity for Zn sorption than did the un-amended acidic one. It can be concluded that biochar derived from sugarcane bagasse could serve as a good amendment material to reclaim acidic soils and to reduce Zn mobility and toxicity in acidic metal-contaminated soils.

已提出应用碱性生物炭作为石灰的替代品来修复酸性土壤。然而，关于生物炭改良剂如何影响酸性土壤中金属的反应和命运仍存在疑问。为了了解添加生物炭如何影响酸性土壤中锌（Zn）的吸附-解吸行为，对初始pH值为4.67的土壤进行了不同的处理[0（对照），1％，3％和6％）。于600°C由甘蔗渣热解产生的生物炭，在80％的持水量下孵育30天。在温育期结束时，测量了重要的土壤化学性质，并进行了批量等温线实验，以确定土壤Zn的吸附-解吸参数。结果表明，经生物炭改性的土壤具有较高的pH值（高达2.5 pH单位），相对于未改良的酸性土壤，其电导率（高达2.66倍）和阳离子交换能力（高达42％）。添加生物碳还导致土壤可交换钙，镁，钠和钾阳离子的显着增强。吸附和解吸等温线实验均表明，经生物炭改良的土壤保留锌的能力明显高于对照。而且，生物炭改良土壤对锌的吸附亲和力比未改良酸性土壤高。可以得出结论，源自甘蔗渣的生物炭可以作为改良酸性土壤的改良材料，并减少在酸性金属污染土壤中的Zn迁移率和毒性。添加生物碳还导致土壤可交换钙，镁，钠和钾阳离子的显着增强。吸附和解吸等温线实验均表明，经生物炭改良的土壤保留锌的能力明显高于对照。而且，生物炭改良土壤对锌的吸附亲和力比未改良酸性土壤高。可以得出结论，源自甘蔗渣的生物炭可以作为改良酸性土壤的改良材料，并减少在酸性金属污染土壤中的Zn迁移率和毒性。添加生物碳还导致土壤可交换钙，镁，钠和钾阳离子的显着增强。吸附和解吸等温线实验均表明，经生物炭改良的土壤保留锌的能力明显高于对照。而且，生物炭改良土壤对锌的吸附亲和力比未改良酸性土壤高。可以得出结论，源自甘蔗渣的生物炭可以作为改良酸性土壤的改良材料，并减少在酸性金属污染土壤中的Zn迁移率和毒性。吸附和解吸等温线实验均表明，经生物炭改良的土壤保留锌的能力明显高于对照。而且，生物炭改良土壤对锌的吸附亲和力比未改良酸性土壤高。可以得出结论，源自甘蔗渣的生物炭可以作为改良酸性土壤的改良材料，并减少在酸性金属污染土壤中的Zn迁移率和毒性。吸附和解吸等温线实验均表明，经生物炭改良的土壤保留锌的能力明显高于对照。而且，生物炭改良土壤对锌的吸附亲和力比未改良酸性土壤高。可以得出结论，源自甘蔗渣的生物炭可以作为改良酸性土壤的改良材料，并减少在酸性金属污染土壤中的Zn迁移率和毒性。