Contrasted Effects of Biochar on Maize Growth and N Use Efficiency Depending on Soil Conditions

Abstract

Biochar amendment may improve crop growth through its nutrients and indirect fertility. However, this improvement varies in a wide range of biochars, crops, and soils. Our objectives were to determine the response of crop growth to biochar amendment and to assess the N use efficiency relative to the biochar and the soil types. In this pot experiment, we investigated five typical agricultural soils in China amended with two biochars. Four treatments were designed: the soil itself as a control, the soil amended with 1% biochar, the soil with fertilizer NPK, and the soil with added biochar and fertilizer. Biochar amendment increased the maize biomass and the N use efficiency in the red soil (p<0.05) but not in the other four soils (p>0.05). In the red soil, the biomass under biochar+NPK was 2.67-3.49 times higher than that of only NPK, and 1.48-1.62 times higher than that of only biochar amendment, 21-36 and 35-42% of which were contributed from biochar fertility and indirect fertility, respectively. This study indicates that biochar amendment is very plausible for the red soil but has a minor or even negative effect on the other four soils in China.

Effects of biochar and nitrogen fertilizer on soil physicochemical properties, nitrogen use efficiency and upland rice (Oryza sativa) yield grown on an Alfisol in Southwestern Nigeria

“…Studies have shown that deriving an appropriate N-recovery index (%) could be used as an indicator for evaluating applied fertilizer use efficiency (Agegnehu et al 2016). Previous studies reported 75% increase in maize biomass relative to NPK fertilizer alone when biochar and NPK fertilizer were combined at different ecological zones in southern China (Zhu et al 2015). Studies by Gathorne-Hardy et al (2009) also reported over 30% increase in barley yield when biochar and N fertilizer were co-applied.…”

Investigations of the effect of the amount of biochar on soil porosity and aggregation and crop yields on fertilized black soil in northern China

“…Although many reports of biochar addition resulting in improved crop yields have been reported, some studies have described contradictory negative results for specific soil conditions [14], with improvements in soil quality affording no improvements in crop growth yields. Jeffery et al (2017) reported that biochar addition is most likely to benefit agriculture in low-nutrient, acidic soils that are present in the tropics [15].…”

Characterization of Novel Torrefied Biomass and Biochar Amendments

“…Biochar further has lower N content and high compositional variability dependent upon the conditions of pyrolysis and feedstock utilized [36] [37]. Biochar effects may also prove to be soil specific [38]. To date, biochar utilization has been predominately focused in biocoal, syngas, bio-oil, and hydrothermal production of biomass under anaerobic conditions.…”

“…To date, biochar utilization has been predominately focused in biocoal, syngas, bio-oil, and hydrothermal production of biomass under anaerobic conditions. Ultimately, biochar application to soils is dependent upon parent material, temperature rates, and application rates [36] [37] [38] [39].…”