title: Negative interactive effects between biochar and phosphorus fertilization on phosphorus availability and plant yield in saline sodic soil.
abstract: Little is known about the interactive effects between biochar application and phosphorus (P) fertilization on plant growth and P uptake. For this purpose, five wheat straw biochars (produced at 25°C, 300°C, 400°C, 500°C and 600°C for 4h) with equal P (36mgkg(-1)) amount, with and without additional P fertilization (100mgkg(-1)) were applied in a pot experiment to investigate the growth of Suaeda salsa and their uptake of P from biochar and P fertilization amended saline sodic soil. Soil P fractions, dry matter yield, and plant P concentrations were determined after harvesting 90days. Our results confirmed that relatively lower pyrolysis temperature (<400°C) biochar retained P availability and increased plant growth. The plant P concentration was significantly correlated with NaHCO3-Pi (P<0.05), and NaOH-Pi (P<0.1) during early incubation time (4days) for biochar amended soil. As revealed by statistical analysis, a significant (P<0.05) negative (antagonistic) interaction occurred between biochar and P fertilization on the biomass production and plant P concentration. For plant biomass, the effects size of biochar (B), P, and their interaction followed the order of B×P (0.819)>B (0.569)≈P (0.568) based on the partial Eta squared values whereas the order changed as P (0.782)>B (0.562)>B×P (0.515) for plant P concentration. When biochar and P fertilization applied together, phosphate precipitation/sorption reaction occurred in saline sodic soil which explained the decreased plant P availability and plant yield in saline sodic soil. The negative interaction effects between biochar and P fertilization indicated limited utility value of biochar application in saline sodic soil.
authors.affiliation: Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Xu
authors.affiliation: Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: You
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China; School of Life Science, Ludong University, Yantai 264025, China.
authors.forename: Junna
authors.initials: J
authors.lastname: Sun
authors.affiliation: Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China; Institute of Agro-Biotechnology, Jiangsu Academy of Agriculture Sciences, Nanjing 210014, China. Electronic address: shaohongbochu@126.com.
authors.forename: Hongbo
authors.initials: H
authors.lastname: Shao
mesh_terms: D001682:Biological Availability; D002606:Charcoal / Q000737:chemistry*; D019663:Chenopodiaceae / Q000254:growth & development* / Q000378:metabolism*; D005308:Fertilizers / Q000032:analysis*; D010758:Phosphorus / Q000378:metabolism*; D054712:Salinity; D012987:Soil / Q000737:chemistry*
chemical_list: D005308:Fertilizers; D012987:Soil; C540010:biochar; D002606:Charcoal; D010758:Phosphorus
keywords: Bioassay test; Biochar; Interaction effect; Phosphorus; Saline sodic soil