Fe-modified biochar combined with mineral fertilization promotes soil organic phosphorus mineralization by shifting the diversity of phoD-harboring bacteria within soil aggregates in saline-alkaline paddy soil

• Published in: Journal of soils and sediments Vol. 23; no. 2; pp. 619 - 633
• Main Authors: Liu, Lu, Zhang, Shirong, Chen, Mengmeng, Fei, Chao, Zhang, Wenju, Li, Yuyi, Ding, Xiaodong
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.02.2023; Springer Nature B.V
• Subjects: Aggregates; Agrochemicals; Alkaline phosphatase; Alkaline soils; Bacteria; Bioavailability; biochar; Biological fertilization; Charcoal; Earth and Environmental Science; Environ Risk Assess; Environment; Environmental Physics; Fertilization; Fertilizers; field experimentation; Iron; Mineral fertilizers; Mineralization; Organic carbon; Organic phosphorus; paddies; paddy soils; Phosphatase; Phosphorus; Redundancy; Relative abundance; river deltas; Saline soils; Sec 2 • Global Change; Soil; Soil aggregates; Soil bacteria; Soil improvement; Soil microorganisms; soil organic carbon; soil organic phosphorus; Soil Science & Conservation; Soil stability; Soil structure; Soils; Sustainable Land Use • Research Article; Yellow River; Yellow River; Alkaline phosphatase availability; Phosphorus availability; Organic phosphorus mineralization; PhoD-harboring bacteria; Fe-modified biochar
• ISSN: 1439-0108; 1614-7480
• DOI: 10.1007/s11368-022-03335-4

Purpose Fe-modified biochar could promote soil organic phosphorus (P o ) mineralization and phosphorus (P) bioavailability; however, the role of biochar and Fe-modified biochar in driving the mineralization of P o by phoD-harboring bacteria in soil aggregates was less known, especially in saline-alkali paddy soil. Methods A 5-year paddy field experiment was conducted in Yellow River Delta, in which four fertilization treatments were designed: no fertilization (Control), inorganic fertilizer (NPK), NPK + biochar (BC), and NPK + Fe-modified biochar (FeBC). Results Compared with NPK treatment, the proportion of macroaggregates in BC and FeBC treatments was significantly increased by 10.42% and 24.67%, respectively. And the mean weight diameter was also increased under biochar treatments. Redundancy analysis (RDA) indicated that oxalate-extractable Fe was a main factor in the stability of soil aggregates, which was significantly increased in FeBC treatment. Meanwhile, the relative abundance of phoD-harboring bacteria was increased in both BC and FeBC treatments, which was driven by the content of soil organic carbon. And the diversity of phoD-harboring bacteria was positively correlated with P o mineralization. Meanwhile, compared with NPK treatment, the activity of alkaline phosphatase in macroaggregate was increased by 39.1% in FeBC treatments, which also promoted the mineralization of soil P o . Conclusions Therefore, biochar addition, especially Fe-modified biochar combined with mineral fertilization, was a better strategy in improving soil aggregate structure and promoting P o mineralization in saline-alkaline paddy soil.