Using Woody Biochar to Conserve Water and Sustain Agriculture in Maine

Socio‐Economic 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)

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’s 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’s 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 UMaine, 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’s underutilized forest biomass, and assist policymakers in planning future support efforts for biochar producers and farmers who intend to use biochar products.

Team Leader: Ling Li, Assistant Professor of Sustainable Bioenergy Systems, School of Forest Resources, UMaine

Team Members:

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