Restoring ecological function to industrial barrens via manipulation of soil chemical environments

Anthropogenic industrial activities release toxic pollutants into the environment that contaminate air, water, and soil systems. Soil contamination adversely impacts soil microbiomes and lower microbial function, including enzyme production, rendering some soils barren and inactive. Barren soils do not grow plants and fail to provide ecosystem services to their environment. Previous research by the Principal Investigator’s research group has shown that the addition of artificial root exudates (AREs) to soils can significantly increase microbial metabolism and respiration rates in uncontaminated, vegetated soils. However, very limited data and fundamental knowledge are available about the impact of ARE addition on microbial activity in contaminated and barren soils. The overarching goal of this project is to investigate changes in soil microbial respiration, enzyme activity, plant productivity, and microbial contaminant degradation potential that result from the addition of AREs to contaminated and barren soils. To advance this goal, the project research team will investigate the addition and impact of ARE solutions consisting of mixtures of compounds that are found in natural root exudates. The successful completion of this project will benefit society through the generation of new data and fundamental knowledge that could be used to guide the design and implementation of more sustainable and cost-effective solutions from the remediation and restoration of contaminated and barren soils. Additional benefits to society will be achieved through student education and training including the mentoring of one post-doctoral fellow, one graduate student, and two undergraduate students at Montclair State University, an R2-rated Hispanic Serving Institution (HSI). Soils provide vital ecological services that include nutrient cycling and carbon storage. Soil contaminants interfere with these ecological services, decreasing microbial function and rendering some soils barren. Previous research has shown that artificial root exudates (AREs) can increase microbial metabolism and respiration rates in uncontaminated, vegetated soils, but their effects on contaminated, barren soils are not known. The goal of this project is to investigate changes in soil microbial respiration, enzyme activity, and plant productivity that result from the addition AREs to contaminated (post-industrial) and barren soils. The proposed AREs will consist of mixtures of compounds that are found in natural root exudates. The specific objectives of the research are to 1) quantify the optimal doses and effects of artificial ARE addition on microbial respiration and function in model contaminated and barren soils from 3 post-industrial sites in New Jersey; 2) compare the effectiveness of easy-to-implement single - versus labor-intensive repeated artificial root exudates addition schedules in revitalizing contaminated soils; and 3) evaluate the potential of ARE additions to stimulate microbial degradation of polycyclic aromatic hydrocarbons (PAHs) in contaminated soils. The successful completion of this project has the potential for transformative impact though the generation of new data and fundamental knowledge on the restoration and maintenance of microbial activity following the addition of AREs to contaminated and baren soils including microbial awakening from dormancy, changes in extracellular enzyme activity, and/or soil organic matter availability. To implement the education and training goals of the project, the Principal Investigator (PI) proposes to leverage existing programs at Montclair State University such as the Louis Stokes Alliance for Minority Participation (LSAMP) to recruit and mentor undergraduate students from underrepresented groups to work on the project. In addition, the research team plans to communicate and share the project research findings with local and state administrators and stakeholders that are interested in the implementation of novel strategies/solutions to revitalize contaminated (post-industrial) and barren soils in New Jersey.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.