Impact of Biochar Amendment on Soil Properties and Organic Matter Composition in Trace Element-Contaminated Soil

Abstract

The application of biochar as an organic amendment in polluted soils can facilitate their recovery by reducing the availability of contaminants. In the present work, the effect of biochar application to acid soils contaminated by heavy metal spillage is studied to assess its effect on the quantity and composition of soil organic matter (SOM), with special attention given to soil humic acids (HAs). This effect is poorly known and of great importance, as HA is one of the most active components of SOM. The field experiment was carried out in 12 field plots of fluvisols, with moderate and high contamination by trace elements (called MAS and AS, respectively), that are located in the Guadiamar Green Corridor (SW Spain), which were amended with 8 Mg·ha−1 of olive pit biochar (OB) and rice husk biochar (RB). The results indicate that 22 months after biochar application, a noticeable increase in soil water holding capacity, total organic carbon content, and soil pH were observed. The amounts of oxidisable carbon (C) and extracted HAs in the soils were not altered due to biochar addition. Thermogravimetric analyses of HAs showed an increase in the abundance of the most thermostable OM fraction of the MAS (375–650 °C), whereas the HAs of AS were enriched in the intermediate fraction (200–375 °C). Spectroscopic and chromatographic analyses indicate that the addition of biochar did not alter the composition of the organic fraction of HAs, while Cu, Fe, and as were considerably accumulated at HAs.

Use of Biostimulants in Energy Crops as a New Approach for the Improvement of Performance Sequestration CO2

“…These results indicate that the obtained pellets have the potential to be used as fertilizers or as additives to fertilizers and biostimulants. This is corroborated by the findings of other researchers, such as De la Rosa and colleagues, which demonstrate that biocarbon has a beneficial impact on soil properties, including a reduction in acidity and an enhancement in water retention capacity [139].…”

Changes in soil organic matter molecular structure after five-years mimicking climate change scenarios in a Mediterranean savannah

“…The presence of isoprenoids (cis-2-Methyl-7-octadecene; hexahydrofarnesyl acetone) remained constant although a slight decrease was observed with time (Table 1). These compounds are probably rest of pigments side chains, mainly chlorophyll, frequently found in humic substances (de la Rosa et al, 2022). A significantly higher ISO abundance was detected under the tree canopy (1.13 ± 0.19 under the tree canopy; 0.61 ± 0.03 in open pasture, p = 0.000).…”

Biochar enhanced phytostabilization of heavy metal contaminated mine tailings: A review

“…Acidification of tailings soil can lead to the mobility of heavy metals and toxicity to plants increased, and lead to plant deficiency of P, Ca, K, Mg, and Mo (Dai et al, 2017). Many studies have reported a significant increase in soil pH after biochar application (De la Rosa et al, 2022). Aamer et al (2020) observed that 2% biochar application increased soil pH from 5.48 to 6.11.…”