Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China.
Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Shanghai Engineering Research Center of Biotransformation of Organic Solid Waste, School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China; Institute of Eco-Chongming, No. 20 Cuiniao Road, Chen Jiazhen, Shanghai 200062, China.
Sci Total Environ. 2020 Aug 20;731:138938. doi: 10.1016/j.scitotenv.2020.138938. Epub 2020 May 6.
Because salinity of coastal soils is drastically increasing, the application of biochars to saline-alkali soil amendments has attracted considerable attention. Various Solidago-canadensis-L.-derived biochars prepared through pyrolysis from 400 to 600 °C were applied to coastal saline-alkali soil samples to optimise the biochar pyrolysis temperature and investigate its actual ecological responses. All biochars reduced the soil bulk density and exchangeable sodium stress and increased soil water-holding capacity, cation exchange capacity, and organic matter content. Principal-component-analysis results showed that pyrolysis temperature played an important role in the potential application of biochars to improve the coastal saline-alkali soil, mainly contributed to ameliorating exchangeable sodium stress and decreasing biochar-soluble toxic compounds. Furthermore, soil bulk density and organic matter, as well as carboxylic acids, phenolic acids and amines of biochar were major driving factors for bacterial community composition. Compared to low-temperature biochar (pyrolyzed below 550 °C), which showed higher toxicity for Brassica chinensis L. growth due to the higher content of carboxylic acids, phenols and amines, high-temperature biochar (pyrolyzed at or above 550 °C) possessed less amounts of these toxic functional groups, more beneficial soil bacteria and healthier for plant growth. Therefore, high-temperature biochar could be applied as an effective soil amendment to ameliorate the coastal saline-alkali soil with acceptable environmental risk.
由于沿海土壤盐分急剧增加，生物炭在盐碱土改良中的应用引起了广泛关注。通过在 400 至 600°C 之间热解制备的各种源自加拿大一枝黄花的生物炭被应用于沿海盐碱土样本中，以优化生物炭热解温度并研究其实际生态响应。所有生物炭均降低了土壤容重和交换性钠胁迫，增加了土壤持水能力、阳离子交换能力和有机质含量。主成分分析结果表明，热解温度在生物炭应用于改善沿海盐碱土方面起着重要作用，主要有助于改善交换性钠胁迫和降低生物炭可溶性有毒化合物。此外，土壤容重和有机质，以及生物炭中的羧酸、酚酸和胺，是细菌群落组成的主要驱动因素。与低温生物炭（低于 550°C 热解）相比，高温生物炭（550°C 及以上热解）由于含有更多的羧酸、酚类和胺类物质，对油菜生长的毒性更高，高温生物炭含有较少的这些有毒官能团，更多的有益土壤细菌，更有利于植物生长。因此，高温生物炭可作为一种有效的土壤改良剂，用于改善沿海盐碱土，同时具有可接受的环境风险。
