Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, Zhejiang University, Hangzhou, 310058, PR China.
The Agricultural Technology Extension Center of Hangzhou City, Zhejiang, 310020, PR China.
Chemosphere. 2021 Jan;262:127828. doi: 10.1016/j.chemosphere.2020.127828. Epub 2020 Jul 31.
Cadmium (Cd) pollution is a widespread environmental problem that decreases crop production, destroys the microbial ecology of soil, and poses a severe risk to human health. Organo-chemical amendment is a cost-effective, eco-friendly, and community-acceptable widely applied an in situ technique for metal-contaminated farmland. In this study, we mixed lime, zeolite, calcium magnesium phosphate fertilizer, and biochar in a mixture ratio of 71:23:5:1 to form a mixed amendment. Field and laboratory experiments were conducted to study the effects of the mixed amendment on soil exchangeable Cd content, plant Cd accumulation, and soil microbial community. It was found that the application of 0.5% mixed amendment decreased exchangeable soil Cd by more than 85% and 64% in wheat and rice season, respectively, compared with control (CK), without increasing pH. Moreover, the application of 0.5% mixed amendment decreased Cd accumulation in grains by 22.9% and 41.2% in wheat and rice season, respectively, compared to CK. The result of phospholipid fatty acids (PLFAs) shows that the level of soil microbial diversity and species richness under mixed amendment treatments were higher than in lime treatment, indicating more copiotrophic conditions and faster rate of nutrient turnover in mixed amendment than pure lime treatment. Hence, it concluded that the mixed amendment has a strong effect on fixing exchangeable soil Cd and reducing the accumulation of Cd in crops. Finally, it was observed that the mixed amendment improved the soil microbial community structure and accelerate the rate of nutrient turnover by microbes under this favorable condition comparative to individual treatments.
镉（Cd）污染是一个广泛存在的环境问题，它会降低作物产量，破坏土壤微生物生态，对人类健康构成严重威胁。有机化学改良剂是一种经济有效、环保且社区可接受的原位技术，可用于受金属污染的农田。在本研究中，我们将石灰、沸石、钙镁磷肥和生物炭按 71:23:5:1 的比例混合形成混合改良剂。进行了田间和实验室实验，以研究混合改良剂对土壤可交换态 Cd 含量、植物 Cd 积累和土壤微生物群落的影响。结果发现，与对照（CK）相比，应用 0.5%混合改良剂可使小麦和水稻季土壤可交换态 Cd 分别减少 85%和 64%，而 pH 值没有增加。此外，与 CK 相比，应用 0.5%混合改良剂可使小麦和水稻季谷物中 Cd 积累量分别减少 22.9%和 41.2%。磷脂脂肪酸（PLFA）的结果表明，与石灰处理相比，混合改良剂处理下土壤微生物多样性和丰富度水平更高，这表明混合改良剂处理下的土壤具有更多的富养生物和更快的养分周转率。因此，可以得出结论，混合改良剂对固定土壤可交换态 Cd 和降低作物 Cd 积累具有很强的作用。最后，与单独处理相比，在这种有利条件下，观察到混合改良剂改善了土壤微生物群落结构并加速了微生物的养分周转率。
