Lin Shaoying, Wang Weiqi, Sardans Jordi, Lan Xingfu, Fang Yunying, Singh Bhupinder Pal, Xu Xuping, Wiesmeier Martin, Tariq Akash, Zeng Fanjiang, Alrefaei Abdulwahed Fahad, Peñuelas Josep
Key Laboratory of Humid Subtropical Eco-Geographical Process, Ministry of Education, Fujian Normal University, Fuzhou 350007, China; Institute of Geography, Fujian Normal University, Fuzhou 350007, China.
Key Laboratory of Humid Subtropical Eco-Geographical Process, Ministry of Education, Fujian Normal University, Fuzhou 350007, China; Institute of Geography, Fujian Normal University, Fuzhou 350007, China.
Sci Total Environ. 2022 Jun 10;824:153783. doi: 10.1016/j.scitotenv.2022.153783. Epub 2022 Feb 14.
Incorporating amendments of industrial waste such as biochar and steel slag in cropland has been used to enhance the storage of soil organic carbon (SOC) while sustaining crop production. Short-term laboratory and field studies have identified important influences of biochar on active SOC fractions associated with soil microbial activity in paddy soils, but the long-term effects remain poorly understood. To address these knowledge gaps, we examined the effects of slag, biochar, and slag+biochar treatments on total SOC concentration, active SOC fractions and soil microbial communities in a paddy field two years after incorporation. Across both two seasons, the addition of slag, biochar, slag+biochar increased soil salinity by 26-80%, 1.3-37% and 42-79%, and also increased soil pH by 0.8-5.7%, 2.1-2.4% and 4.0-6.3%, respectively, relative to the control. SOC concentration was higher in the slag, biochar, and slag+biochar treatments across both rice seasons by 4.3-5%, 0.5-17% and 4.3-7%, respectively. Soil C-pool activity and C-pool management indices in the late paddy season were significantly lower in the slag+biochar treatment than the control by 26.3 and 21.3%, respectively, indicating that the amendments contributed to the stability of SOC. The C concentrations of the biochar and slag amendments affected bacterial abundance more than fungal abundance and affected C cycling. Our study suggests that combined slag and biochar amendments may increase bacterial abundance that may maintain SOC storage and reduce the abundances of potential SOC decomposers in key functional genera, indicating strong coupling relationships with changes of soil properties such as salinity, pH, and SOC concentration. These outcomes due to the amendments (e.g. slag+biochar) may increase microbial C-use efficiency and support the stability of active SOC fractions, with opportunities for long-term C sequestration.
在农田中添加生物炭和钢渣等工业废弃物改良剂，已被用于增强土壤有机碳（SOC）的储存，同时维持作物产量。短期的实验室和田间研究已经确定了生物炭对稻田土壤中与土壤微生物活性相关的活性SOC组分的重要影响，但长期影响仍知之甚少。为了填补这些知识空白，我们在添加改良剂两年后，研究了钢渣、生物炭和钢渣+生物炭处理对稻田土壤总SOC浓度、活性SOC组分和土壤微生物群落的影响。在两个季节中，相对于对照，添加钢渣、生物炭、钢渣+生物炭分别使土壤盐分增加了26 - 80%、1.3 - 37%和42 - 79%，土壤pH值分别增加了0.8 - 5.7%、2.1 - 2.4%和4.0 - 6.3%。在两个水稻季节中，钢渣、生物炭和钢渣+生物炭处理的SOC浓度分别高出4.3 - 5%、0.5 - 17%和4.3 - 7%。在晚稻季，钢渣+生物炭处理的土壤碳库活性和碳库管理指数分别比对照显著降低了26.3%和21.3%，表明这些改良剂有助于SOC的稳定性。生物炭和钢渣改良剂的碳浓度对细菌丰度的影响大于真菌丰度，并影响碳循环。我们的研究表明，钢渣和生物炭联合改良剂可能会增加细菌丰度，这可能维持SOC储存，并降低关键功能属中潜在SOC分解者的丰度，表明与土壤性质如盐分、pH值和SOC浓度的变化存在强耦合关系。这些改良剂（如钢渣+生物炭）带来的这些结果可能会提高微生物碳利用效率，并支持活性SOC组分的稳定性，为长期碳固存提供机会。
