Soil Buffering Capacity Can Be Used To Optimize Biostimulation of Psychrotrophic Hydrocarbon Remediation

Abstract

Effective bioremediation of hydrocarbons requires innovative approaches to minimize phosphate precipitation in soils of different buffering capacities. Understanding the mechanisms underlying sustained stimulation of bacterial activity remains a key challenge for optimizing bioremediationparticularly in northern regions. Positron emission tomography (PET) can trace microbial activity within the naturally occurring soil structure of intact soils. Here, we use PET to test two hypotheses: (1) optimizing phosphate bioavailability in soil will outperform a generic biostimulatory solution in promoting hydrocarbon remediation and (2) oligotrophic biostimulation will be more effective than eutrophic approaches. In so doing, we highlight the key bacterial taxa that underlie aerobic and anaerobic hydrocarbon degradation in subarctic soils. In particular, we showed that (i) optimized phosphate bioavailability outperformed generic biostimulatory solutions in promoting hydrocarbon degradation, (ii) oligotrophic biostimulation is more effective than eutrophic approaches, and (iii) optimized biostimulatory solutions stimulated specific soil regions and bacterial consortia. The knowledge gleaned from this study will be crucial in developing field-scale biodegradation treatments for sustained stimulation of bacterial activity in northern regions.

Evaluating the Impact of Nutrient Doses on Biostimulation of Petroleum Hydrocarbon Biodegradation in Cold Region Soils

“…It should also be noted that the relative abundance of Burkholderiaceae was enhanced in the 1348 mg-N/kg and 115 mg-P/kg and the 104 mg-N/kg and 115 mg-P/kg systems, and Pseudomonadaceae was not dominant in these systems. While these observations agree with evidence in the literature on Pseudomonadaceae and Burkholderiaceae to be known hydrocarbon degraders, ,,,− they also highlight that diesel alone is sufficient to enrich their relative abundance in the soil used in this study. However, the hydrocarbon degradation data (Figures and ) suggest that the addition of nutrients controls the extents and rates of hydrocarbon degradation.…”

“…Siciliano et al highlighted the effects of soil mineralogy on phosphate speciation following phosphate biostimulation, and its impacts on microbial community phenotype and genotype. Mamet et al highlighted cometabolism and syntrophy among anaerobic hydrocarbon degraders to be important drivers of hydrocarbon degradation across different biostimulatory treatments. Of the four reports that studied the impact of different N and P doses on the same soil, only one has detailed TPH degradation data …”

“…Mamet et al highlighted cometabolism and syntrophy among anaerobic hydrocarbon degraders to be important drivers of hydrocarbon degradation across different biostimulatory treatments. Of the four reports that studied the impact of different N and P doses on the same soil, only one has detailed TPH degradation data …”

“…Of the four reports that studied the impact of different N and P doses on the same soil, only one has detailed TPH degradation data. 41 Relatively, few studies have examined the impacts of a wide range of nutrient doses on rates and extents of TPH fractions and microbial community composition changes. Thus, the objectives of this study were to assess how different amounts of nutrient amendment affect biodegradation rates and extents of petroleum hydrocarbons, as well as the soil microbial community composition in a soil slurry freshly spiked with a fixed concentration of Arctic diesel.…”

Experimental Research on the Selected Biofiltration Materials Under Dynamic Conditions

“…Polyurethane foam (PUF) materials have been found to possess the following properties: 1) high porosity facilitates increased contact between hydrogen sulfide and packing materials; 2) high specific surface area, high wettability, and nutrient capacity promote the growth of SOB (Sulfur Oxidizing Bacteria); 3) water retention and drainage capacity are beneficial for cleaning out reactor by-products. Compared to other materials, open-pore synthetic foams offer several advantages, including low density, high specific surface area, high porosity, and reasonable compaction resistance (Mamet et al, 2021). The outcomes of employing polypropylene samples as packing material in various experimental conditions are presented in Table 3 below.…”