Effect of different biochar particle sizes together with bio-organic fertilizer on rhizosphere soil microecological environment on saline–alkali land

Abstract

The application of biochar and bio-organic fertilizers (BOFs) is effective for improving soil ecological environments. However, soil physicochemical properties and the microbiome diversity of rhizosphere soil after the application of different-sized particles of biochar together with BOF in saline–alkali land have not been thoroughly described. A field experiment was performed to investigate the effects of different-sized particles of apple shoot biochar (60, 30, and 10 mesh) together with BOF on soil bacteria (using Illumina high-throughput sequencing) and the physicochemical properties of Mesembryanthemum cordifolium L. f. grown on saline–alkali land. Results indicated that the combined application of BOF and 10–60 mesh biochar reduced the volumetric weight of soil by 14%–29%, respectively, and additionally decreased soil electrical conductivity, increased the aerial biomass of the M. cordifolium L. f. by over 30%, and notably improved soil water–holding capacity, with 60 mesh giving the best results; organic carbon (OC), organic matter (OM), total nitrogen (N), available phosphorus, alkaline nitrogen, total potassium (K), and total phosphorus (P) were all significantly increased by the addition of combined biochar and BOF; thereinto, field capacity, N, P, K, OC, and OM were positively correlated with the bacterial community structure of coapplied biochar and BOF. There were no significant differences in the richness of total bacteria among the treatments; Proteobacteria, Actinobacteria, and Chloroflexi accounted for >70% of the total bacteria in each treatment; Norank_f__Geminicoccaceae and Micromonospora were the dominant genera across the treatments. The findings suggested that plant growth, physicochemical properties, and community diversity of rhizosphere bacteria in saline–alkali land were significantly positively influenced by biochar 60 mesh plus BOF, followed by biochar 10 and 30 mesh plus BOF. This conclusion could facilitate the study of the ecological functions of biochar and BOF, as well as their interactions with salt-tolerant plants on saline–alkali soil, which can be used to provide exploration ideas for saline–alkali land improvement.

Effect of biochar and bioorganic fertilizer on the microbial diversity in the rhizosphere soil of Sesbania cannabina in saline-alkaline soil

“…In the current study, the soil was silty clay and was heavily compacted, leading to low aeration and water permeability of the surface soil, which directly inhibits the growth of plant roots and the absorption of nutrients. Therefore, the addition of porous biochar greatly improved the soil structure, increased soil permeability, and reduced soil VW, which was consistent with Xiao and Meng (2020) and Gu et al (2022) . Moreover, the improved soil porosity by biochar addition due to the abundant pores in the biochar, beneficial for air and water infiltration could be one of the reasons responsible for the enhanced plant growth ( Zheng et al, 2018 ).…”

“…Bacillus species are commercially marketed as biopesticides, biofertilizers, and soil amendments ( Cao et al, 2011 ). It is worth noting that the abundance of Bacillus species in the rhizosphere soil did not increase after the application of Bacillus compound biofertilizer ( Gu et al, 2022 ; Zhu et. al., 2020 ).…”

Impact of Biochar and Bioorganic Fertilizer on Rhizosphere Bacteria in Saline–Alkali Soil

“…However, the addition of BOF had no effect, while B_BOF led to the greatest improvement of all of the treatments. N and P explained a higher proportion of the variation in the rhizosphere bacteria compared to the saline and organic nutrients, which may be owing to the fact that N and P are the main nutrients and limiting factors for plant growth [50], which in turn affected the bacterial changes.…”

Determining Eastern Red Cedar Biochar Soilless Media Supplementation Rates for Potted Ornamental Kale and Chrysanthemum Production

“…The biochar particle size used during our research ranged from 2 mm to 20 mm. In addition to the rate and temperature, the biochar size also affects the plant growth; fine (60 mesh) and medium (30 mesh) biochar resulted in better results and higher available N and P concentrations compared with those observed with coarse (10 mesh) biochar (Gu et al 2022;Sarfraz et al 2020). The increase in P availability might be attributable to the greater surface area and greater particle destruction of smaller particle sizes (Sarfraz et al 2020).…”