PDF(Sci-hub)
Abstract：
Currently, the research and application of biochar in the remediation of heavy metal contaminated soil has become a hotspot, especially regarding the remediation of agricultural land. Biochar has been proved to be effective in reducing the content of available heavy metals in the soil as well as the heavy metals in plants. However, the long-term effectiveness of biochar immobilization has not been widely studied. In this review, retrospective search was carried out on the published literature results concerning remediation effects of biochar on different areas of heavy metal contaminated soil in the recent years, its application in field remediation (several years), and some potential abiotic and biotic factors that may weaken the immobilization effects of biochar. This results indicate that: (1) biochar is widely used in the remediation of heavy metal contaminated soil in different areas and has excellent immobilization effect. (2) Most of the research demonstrate that the immobilization effect of biochar is effective for 2-3 years or according to few results even for 5 years. However, there have been various reports claiming that the immobilization effect of biochar decreases with time. (3) Abiotic factors such as acid rain, flooded environment, changes in soil condition (pH, redox and dissolved organic matter) and changes in biochar (Cl- and alkali leaching) can significantly weaken the immobilization effect of biochar. (4) Biotic factors such as plant roots, earthworms and soil microorganisms can also significantly reduce the immobilization effect of biochar. Therefore, field experiments having longer time span with biochar need to be further carried out, and the developmental research of modified biochar with a more stable immobilization effect also needs further attention.
摘要：
目前,生物炭在重金属污染土壤修复中的研究与应用已成为热点,特别是关于农业土地的修复。生物炭已被证明可有效降低土壤中有效重金属以及植物中重金属的含量。然而,生物炭固定化的长期有效性尚未得到广泛研究。在这次审查中,对近年来已发表的有关生物炭对不同地区重金属污染土壤修复效果的文献进行了回顾性检索,其在现场修复中的应用(几年)，以及一些可能削弱生物炭固定化效果的潜在非生物和生物因素。本研究结果表明:(1)生物炭在不同地区重金属污染土壤修复中应用广泛,具有优异的固定化效果。（2）大多数研究表明，生物炭的固定化效果在2-3年内有效，甚至在5年内效果很少。然而,有各种报道称，生物炭的固定化效果随着时间的推移而降低。（3）酸雨等非生物因素，淹没的环境，土壤条件的变化(pH，氧化还原和溶解的有机物）和生物炭的变化（Cl-和碱浸）可以显着削弱生物炭的固定作用。（4）植物根系等生物因子，蚯蚓和土壤微生物也能显著降低生物炭的固定化效果。因此,需要进一步开展生物炭时间跨度较长的现场实验，具有更稳定固定化效果的改性生物炭的开发研究也需要进一步关注。
