Using Woody Biochar to Conserve Water and Sustain Agriculture in Maine

Socio鈥怑conomic and Environmental Analyses for Using Woody Biochar to Conserve Water and Sustain Agriculture in Maine

Location: University of Maine
Sponsor: Maine Water Resources Research Institute 2023 (104b)

Team Leader: , Assistant Professor of Sustainable Bioenergy Systems, School of Forest Resources, 91福利

Team Members:

  • Yongjiang Zhang, Assistant Professor of Plant Physiology, School of Biology and Ecology.
  • Adam Daigneault, Associate Professor of Forest Policy & Economics, SFR, 91福利.
  • Shane R. O鈥橬eill, Forest Industry Business Development Manager, SFR.
  • Sumon Datta, Assistant Extension Professor and Extension Agricultural Engineer, 91福利 Extension.
  • Lizao Zhang, Assistant Professor of Operations Management, Maine Business School.

Water resources will become scarcer in the future, and agricultural systems in Maine are facing the threat of increasing drought. As an iconic crop, wild (or lowbush) blueberries (Vaccinium angustifolium Ait.) may undergo severe drought impacts because they grow on sandy soils with a low water holding capacity. A study by Co-PI Zhang revealed that chronic water conditions are important in securing berry yield. However, summer precipitation is predicted to decrease, and there will be more rainfall anomalies. Further, climate warming will make crops and soils lose more water. Although irrigation can effectively maintain good water conditions in soils, over 70% of the wild blueberry farmlands in Maine do not have irrigation systems because of the high upfront investment and miscellaneous costs (such as labor, field maintenance, water purchase, and energy for pumping). Besides, sandy wild blueberry soils, due to the coarse texture, could greatly reduce the water use efficiency for both irrigation and precipitation. Biochar additions could be a prominent solution to increase soil water holding of sandy soils and crop productivity. PIs Li and Zhang鈥檚 biochar study found that adding biochar to sandy soils aided the wild blueberry plants by delaying the onset of soil water deficits and leaf water stress in wild blueberries.

Large-scale biochar applications may also help conserve water resources at the regional scale and prevent groundwater contamination by reducing the downward movement of agrichemicals. However, these effects have yet to be investigated. Biochar can alter the soil texture and then affect the water fluxes in the soils amended with biochar. Therefore, the effects of biochar applications on regional water quantity and quality need to be analyzed based on hydrological models. PI Datta found that accurately quantified water fluxes in irrigated soils could eliminate the negative impacts caused by non-beneficial water fluxes on regional water quality, such as the transport of sediments, chemicals, and other harmful constituents to downstream land and water resources, and socio-economic and environmental issues, like increase in the financial viability of irrigation management and greenhouse gas emission as more energy is used to extract, transport, and apply water. Further, biochar has not been widely accepted by Maine鈥檚 farmers for crop applications, which may be due to a lack of sustainable and cost-effective biochar supply from local producers, technical and general information on biochar products and application, policy and regulation support, and successful demonstrations of biochar applications.

This study aims to find solutions or provide strategies to some of these challenges by 1) conducting a field study to assess the effect of biochar on soil water storage, irrigation and precipitation water use efficiency, crop water use, berry production, and cost-benefit trade-off, 2) quantifying the impact of biochar use on regional water quantity and quality, 3) analyzing a supply chain of biochar production and uses, 4) studying the life cycle assessment (LCA) of biochar-to-soil system, and 5) economic and policy assessment of agricultural use biochar.

This project will extend the team’s current projects studying biochar impact on crop production (a USDA NRCS project), climate change impacts on the wild blueberry system (a USDA BNRE project), and drought management techniques (a USDA SCBG project) to the realm of water resources, environmental and socio-economic impacts. The team includes researchers and students from multiple disciplines at 91福利, biochar producers, and wild blueberry farmers of different sizes to take part in the relevant studies. The research outputs will include a hydrological model that can analyze the impact of biochar applications on catchment scale hydrology, strategies for sustaining agricultural and natural ecosystems, and a new option for farmers to manage drought using locally produced biochar products. This project will also help the forest products industry diversify bioproducts made for Maine鈥檚 underutilized forest biomass, and assist policymakers in planning future support efforts for biochar producers and farmers who intend to use biochar products.

Project Report

This project addressed the challenges of water scarcity faced by Maine’s wild blueberry agriculture due to climate change and drought, as over 70% of the wild blueberry farmlands lack irrigation systems. We evaluated the impacts of biochar on soil water storage, efficiency of water use, and its potential regional impacts on water quantity. In addition, we examined the biochar production supply chain, conducted a life cycle assessment of the biochar-to-soil system, and assessed the economic and policy implications of agricultural biochar use. The key research findings reveal that biochar applications at a dosage of 30 cubic yards per acre could save up to 85% of irrigation water when maintaining the soil moisture content at ~30%. This notable difference highlights the biochar鈥檚 high water retention capacity, showing its application can greatly reduce the water needs for wild blueberries. Applying biochar to soil can offset approximately 1,000 kg CO2eq per ton of biochar, compared to other applications, such as energy fuel. A systematic review of global policies for biochar, along with a techno-economic analysis, shows that high production and entry costs require strategic policy interventions, including market-creation policies and regulatory clarity for feedstock procurement. It is recommended that the Northeast US establish scientific certainty and trust, foster a regional network with Canada, and implement multi-instrument strategies that combine incentives, regulatory adjustments, and continued research & development to drive large-scale commercialization.

Products

Presentations

  • Swikar Karki*, Ling Li, Yongjiang Zhang. Effects of Biochar in Improving Soil Moisture in Wild Blueberry Fields. Oral presentation. Presenter: Swikar Karki. 2025 Maine Sustainability and Water Conference, Civic Center, Augusta, ME. March 27, 2025.听

Funding Awarded

  • A framework to combine an economic and policy analysis to identify policy instruments to lower cost of biomass production. Lead PI: Adam Daigneault. Sponsoring organization: USDA-NIFA NE Sun Grant Program. Award No. S006551-USDA.
  • Novel Carbon- Novel Carbon-Sequestering Production of Biochar and Building Materials from Crop Residues to Enhance Crop Yield in the Northeastern United States. Lead PIs: Linfei Li and Ling Li. Sponsoring organization: USDA-NIFA NE Sun Grant Program. Award No. S005078-USDA.

Awards/Achievements听

  • 2025 ELH Research Collaboration Award – Biochar Collaborative. Recipients: Ling Li, Yongjiang Zhang, Adam Daigneault, Shane O鈥橬eill. This award recognizes the collaborative research done by faculty members in different departments across the campus.