生态环境学报2025，Vol.34Issue(12)：1890-1899,10.DOI:10.16258/j.cnki.1674-5906.2025.12.006
藻液添加提升稀土尾矿砂土壤碳氮固持能力
Study on the Enhancement of Carbon and Nitrogen Retention in Rare Earth Tailings Soil by Microalgae
摘要
Abstract
Rare earth tailings soil is barren and deficient in carbon and nitrogen,severely restricting ecological restoration.This study explored the effects of adding active and inactivated microalgae on soil carbon and nitrogen sequestration and aggregate structures.Chlorella pyrenoidosa and nitrogen-fixing Anabaena azotica were selected,and three groups of experiments(active,inactivated,and control)were set up.A total of 20 mL of the algal solution was added weekly for 105 days.The chlorophyll content on the soil surface was measured on days 15,45,and 105,and the soil carbon,nitrogen,and aggregate indicators were determined on day 105.The results showed that:1)Active microalgae increased the soil organic carbon(SOC)and total nitrogen(TN)contents by 151%and 512%compared with the control,respectively,while the inactivated treatment increased them by 171%and 385%,respectively.The TN content in the active group was significantly 26.2%higher than that in the inactivated group,whereas the SOC content in the inactivated group was 7.80%higher than that in the active group.2)The net increases of SOC and TN in the active treatment reached 1.476 g·kg-1 and 0.564 g·kg-1,accounting for 32.4%and 79.0%of the total amounts,respectively;those in the inactivated treatment were 1.832 g·kg-1 and 0.415 g·kg-1,accounting for 37.3%and 73.5%,respectively.3)The inactivated treatment increased coarse particulate organic carbon(CPOC)by 111%compared with the control,whereas the active treatment significantly increased fine particulate organic carbon(FPOC)and mineral-associated organic carbon(MAOC)by 124%and 153%,respectively.Both treatments increased the total particulate nitrogen by 533%and 396%compared with in that the control.4)On day 105,the surface soil chlorophyll contents in the active and inactivated treatments increased by 142%and 106%compared to the initial levels,respectively.5)The addition of microalgae significantly reduced the proportion of silt and clay particles.The active and inactivated treatments increased the mean weight diameter(MWD)of aggregates by 10.3%and 18.3%,respectively,and the geometric mean diameter(GMD)in the active group increased by 10.8%.This study indicates that active and inactivated microalgae synergistically improve carbon and nitrogen sequestration efficiency through photosynthetic carbon fixation and biological nitrogen fixation,promote the formation of aggregates,and provide a new approach for the ecological restoration of tailings.This study clarifies the impact of microalgae restoration on carbon and nitrogen transformation,providing a theoretical foundation for optimizing soil improvement technologies.关键词
微藻/稀土尾矿砂/碳氮固持/团聚体/生态修复Key words
microalgae/rare earth tailings/carbon and nitrogen sequestration/aggregates/ecological restoration分类
农业科技引用本文复制引用
官金顺,蒋新宇,程炯,陈三雄,余世钦..藻液添加提升稀土尾矿砂土壤碳氮固持能力[J].生态环境学报,2025,34(12):1890-1899,10.基金项目
广东省科技计划项目(2023B1212060044) （2023B1212060044）
国家自然科学基金青年基金项目(42201057) （42201057）
广东省重点领域研发计划项目(2022B0111130003) （2022B0111130003）
广东省科学院发展专项资金(2023GDASZH-2023010103) （2023GDASZH-2023010103）
广东省基础与应用基础研究基金项目(2025A1515010758) （2025A1515010758）
