Biochar addition to vineyard soils: Effects on soil functions, grape yield and wine quality

Authors: Garcia-Jaramillo, Manuel; MEYER, KYLIE - Oregon State University; Phillips, Claire; Acosta-Martinez, Veronica; OSBORNE, JAMES - Oregon State University; LEVIN, ALEXANDER - Oregon State University; Trippe, Kristin

Submitted to: Biochar
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/4/2021
Publication Date: 9/3/2021
Citation: Garcia-Jaramillo, M.N., Meyer, K.M., Phillips, C.L., Acosta Martinez, V., Osborne, J., Levin, A.D., Trippe, K.M. 2021. Biochar addition to vineyard soils: Effects on soil functions, grape yield and wine quality. Biochar. 3:565-577. https://doi.org/10.1007/s42773-021-00118-x.
DOI: https://doi.org/10.1007/s42773-021-00118-x

Interpretive Summary: In response to increasing concerns over climate change, soil health, and wine quality, grape growers are seeking improved cropping practices that simultaneously increase yield and quality and maintaining or improving environmental sustainability. To evaluate if biochar meets this need, vineyard trials were established post-harvest in the fall of 2018. Two Oregon sites were chosen with distinct soil types and climates (Willamette Valley and Rogue Valley) but planted with the same grapevine scion/rootstock Pinot noir combination. In 2019, a suite of soil health indicators, plant, and yield variables were measured. We also produced and evaluated wine from each treatment. The application of wood-derived biochar impacted certain soil functions and properties; however, the response of the soils varied across locations. Biochar influenced carbon dynamics by significantly increasing various pools of carbon. Biochar also influenced soil properties by increasing moisture and pH. Although significant improvements in grape yield, quality components, and wine quality were not observed after one year, the significant increase in soil carbon indicates that biochar could play an important role in carbon sequestration.

Technical Abstract: In response to increasing concerns over climate change, soil health, and wine quality, grape growers are seeking new methods (e.g., biochar) to minimize their environmental footprint while increasing productivity and the quality of their products. To explore the potential of biochar-based amendments in sustainable wine grape production, vineyard trials were in the fall of 2018. Two Oregon sites were chosen with distinct soil types and climates (Willamette Valley and Rogue Valley) but planted with the same Pinot noir scion/rootstock combination. Four treatments were applied under vines at each location: no biochar/no tillage (NT); no biochar + tillage (B0); 18 tons ha-1 biochar + tillage (B18); 35 tons ha-1 biochar + tillage (B35). In 2019, a suite of soil health, plant, and crop variables were measured, and wines were produced after harvest. The incorporation of biochar modified the chemical and physical composition of soils at the two studied locations, increasing the bioavailability of carbon and nitrogen, their water holding capacity and the concentration of plant available micro and macro nutrients. However, the addition of biochar had a detrimental effect on the soil enzymatic activity (a reduction between 42 and 63% with the single and double biochar rates, respectively) at least in the short-term. No responses of plant physiology parameters or productivity at either site were found after biochar incorporation when compared with controls. A significant and gradual decrease in the amount of wine tannins was found as a result of biochar application at both application rates in wines produced from grapes from the Woodhall location and decreased the amount of iron-reactive phenolics at the higher rate. Long-term field experiments are required to assess the effects of biochar on soil properties, vine physiology, productivity, and grape and wine quality several years after incorporation.