Influence of Sewage Sludge Biochar on the Microbial Environment, Chinese Cabbage Growth, and Heavy Metals Availability of Soil

Abstract

The effects of sewage sludge biochar (SSB) on the microbial environment, Chinese cabbage yield, and heavy metals (HMs) availability of soil were comprehensively investigated in this study. Results showed that the concentrations of the dehydrogenase (DHA) and urease in the soil added with 10% SSB were 3.60 and 1.67 times as high as that of the control soil, respectively, after planting; the concentrations of the bacteria, fungi, ammonia-oxidizing archaea (AOA), and ammonia-oxidizing bacteria (AOB) in the soil added with 10% SSB after planting reached 2.84, 2.62, 1.76, and 2.23 times, respectively, compared with those of the control group; the weights of the aboveground and underground parts of Chinese cabbage were 5.82 and 8.67 times as high as those of the control group, respectively. Moreover, the addition of SSB enhanced the immobilization of Cr, Ni, and Cd. All in all, SSB can improve the microbial environment of soil and inhibit the availability of HMs, which is very important for their utilization in barren soil.

Chemical speciation and distribution of potentially toxic elements in soilless cultivation of cucumber with sewage sludge biochar addition

“…Khan et al (2014) have found that SSB amendment can lower the concentrations of As, Cr, Co, Ni, and Pb in rice tissues by reducing their EDTA-extractable fraction in soil, while enhancing the bioaccumulation of Cd and Zn. In our previous study, the application of SSB increased the concentrations of dehydrogenase, urease enzymes, fungi, ammonia-oxidizing archaea, and ammonia-oxidizing bacteria and enhanced the immobilization of Cr, Ni, and Cd in the soil, which contributed to an increase in the weight of Chinese cabbage (Yu et al, 2018). Furthermore, a field study has also verified the reduction in Cd accumulation in rice in response to SSB treatment (Zhang et al, 2016).…”

Long‐term effects of sewage sludge–derived biochar on the accumulation and availability of trace elements in a tropical soil

“…This indicates that, among SSBCs, BC300 was the most efficient in making Mn available on an intermediate time scale. A short‐term study also reported a reduction in Mn availability as a direct effect of SSBC application (Yu et al., 2019).…”

Moderate sewage sludge biochar application on alkaline soil for corn growth: a field study

“…Khan et al (2013) found that 5-10 wt% SSB amendment decreased the uptake of some PTEs (As, Cr, Co, Ni, and Pb) in rice tissues as a result of increasing the pH, cation exchange capacity, pore structure, and dissolved organic carbon concentration of acidic soil. In addition, the reduction in PTE bioaccumulation of SSB has been verified in other plants such as grass, Chinese cabbage, and tomato (Hossain et al 2010;Yu et al 2018;Yue et al 2017). In our previous study, we found that 5-10 wt% SSB is the suitable proportion to use in soilless cultivation, and only small amounts of the PTEs in biochar were taken up by cucumber plants (Xie et al 2020b).…”