Most foods sold in northern and remote communities such as Happy Valley-Goose Bay, Labrador are transported from distant places. Handling and long-distance transport causes deterioration in food quality and increases in price. The long-term, sustainable solution for local food security in such communities is therefore to find ways to produce more local foods and fresh vegetables. Factors hindering successful crop production in the Happy Valley-Goose Bay area include late springs and early fall frosts, high soil acidity, low soil organic matter and sandy soil texture (causing the soil to have low cation exchange capacity (CEC), low holding capacity for nutrients and water, and poor soil structure). Problems caused by late springs and early fall frosts can often be addressed by choosing short duration food crops that can be grown during the frost-free days. However, it is not always possible to avoid cold temperatures, because weather patterns are not always predictable. Soil textures cannot be changed, however there are management practices that can be used to enhance retention of nutrients and water, increase soil organic matter, increase CEC, improve soil structure and reduce soil acidity.
Biochar is a carbonous material produced from waste wood or other organic waste, that when applied as soil amendment has the potential to increase soil pH, moisture and nutrient retention capacity, cation exchange capacity (CEC), and organic matter in soils. Biochar remains active in soils and its beneficial effects are longer lasting than when compared to other forms of organic matter such as manure. Most importantly, due to the development of large-scale hydroelectric projects in the province of Newfoundland and Labrador, there is an abundance of waste wood available for local biochar production. Therefore, a multi-year research project was initiated in 2013 to improve the soil fertility and crop productivity of the sandy soils of Happy Valley Goose Bay through biochar application. There were two experiments under this project.
1) In experiment one we aimed to evaluate the effectiveness of biochar as a soil conditioner and fertility enhancer, and to determine its nutrient supply capability when applied both with and without supplementation (fish meal and chemical fertilizers).
2) In experiment two we aimed to evaluate different biochar rates to determine a suitable dose.
In both experiments, biochar application had positive effects on plant growth and crop yields. However, the results from experiment one shows that despite its positive effect on a number of soil parameters, biochar applied without supplementation does not support crop establishment, growth and biomass production. These results indicate that the positive effect of biochar on plant growth and biomass yield is only realized when biochar is applied along with a supplemental nutrient source such as fishmeal or fertilizer. In experiment two, various rates of biochar were applied to evaluate their effect on biomass production. At lower rates, biomass yields increased with biochar rates. However, at higher rate application (80 t C/ha) biomass yield was less than lower biochar applications, indicating there is a rate ceiling for optimal biomass yield. A biochar rate of 40 t C/ha produced the most biomass, however this rate did not provide a statistically significant difference in yield compared to other other biochar rates. This preliminary result suggests that a biochar rate of 10 t C/ha could be sufficient for the sandy soils of Happy Valley-Goose Bay. Biochar application increased soil organic matter and CEC, slightly elevated soil pH and increased a number of plant nutrients. However, we need to continue the experiments over several years to confirm this observation.