Innovations Item Code: IN-2024-2100415
Sector: Environmental sustainability/Circular economy
Description:
Background
Global attention is drawn to environmental pollutants, including heavy metals (HMs), polycyclic aromatic hydrocarbons (PAHs), and BTEX compounds, stemming from oil and gas exploration, reckless oil sludge disposal, and other anthropogenic activities (Onyedikachi et al., 2018). These persistent pollutants pose threats to biodiversity, food security, human health, and climate stability. Conventional remediation methods are costly and often generate harmful by-products, necessitating eco-friendly alternatives like phytoremediation and animal amendments (Nwaichi et al., 2015) to achieve sustainable environment and in addition, maximise the benefits of circular economy.
Phytoremediation involves a promising approach using plants to remove, degrade, or immobilize contaminants in soil. It often requires long remediation periods and may be limited by the types of contaminants and plant species involved. However, Co-planting hyperaccumulating grasses which can resist external stressors like drought in phytoremediation holds high potential for the removal of pollutants from soils. This is due to synergistic interactions between different grass species and their relationships with animal manure as bio-stimulants resulting in increased efficiency of pollutant degradation/removal (Zhang et al., 2023). These interactions overcome the challenges of lengthy planting periods by addressing nutrient deficiencies, enhancing soil contaminant bioavailability for easy uptake by plants and microbes, and more importantly effectively addressing emerging mixed contaminants.
The co-planting of two fast-growing annual weeds, Umbrella sedge (Mariscus alternifolius) and Little Ironweed (Cyanthillium cinereum), has demonstrated remarkable efficacy in removing over 90% of heavy metals (HMs) from spent oil-contaminated soil treated with pig dung. These grasses have proven to possess exceptional absorption capabilities and environmental stress tolerance, making them valuable assets in green remediation approach (Zhang et al., 2023).
Objective:
Therefore, this study sort to elucidate co-planting-animal manure model to boost the remediation of Spent Oil contaminated soils using Mariscus alternifolius and Cyanthillium cinereum, enhanced with swine manure enhancement.(SM ), for the removal of selected HMs (iron, lead, manganese, cadmium, chromium, and arsenic) from Spent Oil (SO)-contaminated soil. Additionally, we further seek to identify and isolate the different microorganism present and as well their genomes using metagenomics, profiling, and amplification to grow pure cultures which can be engineered and used for treatments of polluted soils.
Methods:
1.Soil, Spent oil (SO), swine manure (SM), was collected and characterized for heavy metals (HMs), polycyclic aromatic hydrocarbons (PAHs), and BTEX compounds using ICP-OES and GC/MS.
2.Soil, animal manure and SO samples were characterized for physical, chemical properties, and PAHs, heavy metals, and BTEX concentration analysis using Atomic Absorbtion Spectrophotometer (Ubani et al., 2022).
3.Soil treatment and amendment was dissolved in tetrachloromethane and added to soils to create soil-oil sludge mixtures (SOSM). SOSM was mixed with wood chips at a 1:2 ratio (w:v) to enhance soil structure and aeration.
4.The plants were assessed in the wide at the Michael Okpara fallow agriculture area, carefully uprooted and cut to same lenght of 15cm and was transplanted into the contaminated soil.
5.Co-planting experiments was conducted in triplicate for 90days under controlled greenhouse conditions, following established protocols. Various treatments will be applied, including contaminated soil (CS) alone as control, CS with individual grasses (Mariscus alternifolius or Cyanthillium cinereum), CS with animal manure (SM), and their combinations thereof.
6.The plants were watered twice daily, with the measurements of the shoots, stem and taking to observe the growth rate and physical changes.
7.The residual heavy metals in treated soil was screened to evaluate biodegradation efficiency using Standard methods
Outcomes:
1.Removal of heavy metals up to 90% efficiency for most metals assessed and provision of valuable data for assessing health risks, which would devise effective remediation strategies, and influence policy formulation and strategic implementation.
2.Contribution to a sustainable environment aligned with Sustainable Development Goals 6, 13, and 15, with potential economic benefits.
3.The discovery of novel bacterial and fungal species exhibiting the capability to degrade crude oil and its derivatives pave the way for patentable remediation products which could be genetically engineered into more efficient products, thereby advancing the efficacy of remediation strategies.
4. This study provides insights for development of products for the clean up and restoration of the environmental sustainability and scientific advancement and as well mitigate climate change.
Impacts
1.Recognitions, awards and job creation.
2.The microbial Community DNA extraction and metagenomics will be employed to identify and separate microbial genomes in treated soil. The microbes isolated into pure cultures, characterized using microscopic, biochemical and molecular parameters to identify individual organisms through DNA extraction, agarose gel electrophoresis, and amplified and sequences using PCR using sanger sequencing for fungi ITS gene amplification and sequencing and 16SrRNA for bacteria, then analysed using Bioinformatics tools.
3. I propose further study to isolate microbes from their pure cultures and used for re-treatment alone and in combinations with the most effective microbial culture further enhanced through genetic engineering via whole genome sequencing and mapping to coapt desired genes.
References
1. Li, Y., Lin, J., Huang, Y., Yao, Y., Wang, X., Liu, C. & Yu, F. (2020). Bioaugmentation-assisted phytoremediation of manganese and cadmium co-contaminated soil by Polygonaceae plants (Polygonum hydropiper L. and Polygonum lapathifolium L.) and Enterobacter sp. FM-1. Plant and Soil, 448, 439-453.
2. Nwaichi, E. O., Frac, M., Nwoha, P. A., & Eragbor, P. (2015). Enhanced phytoremediation of crude oil-polluted soil by four plant species: effect of inorganic and organic bioaugumentation. International journal of phytoremediation,17(12), 1253-1261.
3. Onyedikachi, U. B., Belonwu, D. C., & Wegwu, M. O. (2018). Human health risk assessment of heavy metals in soils and commonly consumed food crops from quarry sites located at Isiagwu, Ebonyi State. Ovidius University Annals of Chemistry, 29(1), 8-24.
4. Ubani, O., Atagana, H. I., Selvarajan, R., & Ogola, H. J. (2022). Unravelling the genetic and functional diversity of dominant bacterial communities involved in manure co-composting bioremediation of complex crude oil waste sludge. Heliyon, 8(2), e08945.
5. Yu, Y., Yang, Q., Petropoulos, E., & Zhu, T. (2022). ITS3/ITS4 outperforms other ITS region and 18S rRNA gene primer sets for amplicon sequencing of soil fungi. European Journal of Soil Science, 73(6), e13329.
6. Zhang, Y., Li, M., Su, A., Lv, X., Qiu, Y., & Xu, Y. (2023). Co-planting improves the phytoremediation efficiency of combined phenanthrene and copper co-contaminated soils. Journal of Cleaner Production, 382, 135380.
Stage of Innovation: Proof of Concept (You have created something to show the innovation can work)
Problem:
The proposed co-planting-microbe synergies for enhanced bioremediation of Spent Oil-contaminated soil can address several significant environmental and societal problems:
1.Environmental Pollution: Spent oil and other petroleum derivatives originates from crude oil containing various contaminants such as heavy metals and Polycyclic Aromatic Hydrocarbons, which pose significant threats to soil and water quality, biodiversity, and ecosystem health. By effectively degrading these contaminants, the proposed approach helps mitigate environmental pollution and its associated impacts.
2.Sustainable Agriculture: Contaminated soil can significantly impact agricultural productivity and food security. By remedying soil contamination through co-planting and microbial synergies, the proposed approach can contribute to the restoration of agricultural lands, thereby promoting sustainable farming practices and ensuring food security.
3.Health Risks Mitigation: Contaminants present in Spent Oil-contaminated soil can pose serious health risks to humans, animals, and plants through direct exposure or through the food chain. By removing or degrading these contaminants, the proposed approach helps mitigate health risks associated with soil contamination.
4.Climate Change Mitigation: Crude oil extraction and its subsequent contamination of soil and water contribute to greenhouse gas emissions and climate change. By promoting the use of eco-friendly remediation techniques, the proposed approach contributes to climate change mitigation efforts.
5.Soil Contamination Remediation: Traditional methods of soil contamination remediation can be costly, time-consuming, and often generate harmful by-products. The proposed method offers an eco-friendly and cost-effective alternative, utilizing natural processes such as phytoremediation and microbial degradation to restore contaminated soils.
6.Resource Conservation: Utilizing natural processes such as phytoremediation and microbial degradation minimizes the need for synthetic chemicals and energy-intensive remediation techniques, thereby conserving resources and reducing the ecological footprint of soil remediation efforts.
7.Community Engagement and Empowerment: By disseminating findings through reputable media outlets and engaging with local communities, the proposed research can raise awareness about environmental issues and empower communities to actively participate in remediation efforts and environmental stewardship.
Overall, the proposed co-planting-microbe synergies approach offers a holistic and sustainable solution to the complex problem of Spent Oil-contaminated soil, addressing environmental, societal, and economic challenges simultaneously.
Unique Selling Point: Currently, various methods are being employed to remediate crude oil sludge-contaminated soil, including physical, chemical, and biological approaches. Some common remediation techniques include excavation and disposal, soil washing, thermal desorption, chemical oxidation, and bioremediation. However, each of these methods has its limitations, including high costs, long remediation periods, the generation of harmful by-products, and potential damage to soil structure and fertility. My own approach: The synergies between the plants improve the effectiveness of phytoremediation by using enzyme activities within the holobiont, reducing nutrient deficiencies, increasing the bioavailability of contaminants, and treating mixed contaminants effectively. Additionally, traditional bioremediation approaches focus solely on microbial activity. The proposed approach integrates the co-planting of specific grass species known for their hyperaccumulating abilities. The co-planting synergies, coupled with biostimulants like animal manure (pig dung), harness the natural abilities of microorganisms to degrade contaminants in soil by improving the efficiency of contaminant withdrawal and leveraging the siderophore and endophyte associations within the community (plants and microbes). The cost effectiveness of the co-planting-microbe synergies approach offers a more eco-friendly, and sustainable alternative. By utilizing natural processes and promoting plant-microbe interactions, this approach minimizes the need for synthetic chemicals and energy-intensive techniques, thus reducing costs and environmental impact. The process is harmless and completely environmentally friendly; aside from that, it advocates a circular economy as animal manure like pig dung is readily available at animal farms. This waste can be maximised to create wealth and jobs, reduce the bad odour that stereotypes most animal farms, especially pig farms, and also reduce the green gases released at such farms, which goes a long way toward mitigating climate change. Unlike conventional remediation methods that may lack community engagement and participation, the proposed approach emphasizes dissemination of findings through reputable media outlets and engagement with local communities. By raising awareness about environmental issues and empowering communities to participate in remediation efforts, the proposed approach fosters a sense of ownership and responsibility towards environmental stewardship. Overall, the current remediation methods have their merits, but they also come with limitations such as high costs, long remediation periods, and potential environmental damage. The proposed co-planting-microbe synergies approach offers a novel and holistic solution that addresses these limitations by integrating plant-microbe interactions to enhance remediation efficiency, minimize costs, and promote environmental sustainability.