Fall bedding is a common practice in potato production in southern Alberta. The practice, which involves irrigation, broadcasting of fertilizer, plowing, and the formation of beds, aims to provide favorable soil structure conditions in the spring. It is also a practical approach, allowing growers to prepare the soil in a period where other crops require less time and labor. However, these fall activities may have effects on soil fertility and crop nutrient availability as there is a large time lag between nutrient application and crop uptake. This time lag may decrease nutrient use efficiency and increase greenhouse gas (GHG) emissions, in particular CO2 and N2O. Due to the large swaths of uncovered ground, potato fields are also at a high risk of wind erosion during the off-season period, which can severely impact soil health and fertility in the long term. Irrigated agriculture increases overall N2O emissions due to increases in soil moisture levels and a decrease in aeration. Currently, the impact of bedding choices and timing on potato yield, soil erosion, and GHG emissions in southern Alberta is poorly understood. In this project, we will combine field experiments and computer simulations to quantify the impact of bedding choices and timing and their interaction with irrigation practices on potato production and soil health.

The overall project aims to optimize washing parameters in pig buildings to ensure good sanitation while minimizing water usage. The objective of the present study was to evaluate the efficacy of washing protocols as well as the use of hot and cold water carried out in experimental and commercial-scale buildings. Evaluation criteria included water consumption, washing time, and cleanliness of washed surfaces. Cleanliness was measured, at 1 hour and 24 hours after washing, by both measuring adenosine triphosphate (ATP) bioluminescence and by a rating scale grading the enzymatic reaction level. Using hot water resulted in a significant 31% reduction in water consumption per m² compared to cold water. Additionally, the practice involving application of soap after high-pressure washing or a pre-wash led to a reduction in washing time of about 48.5% compared the practice involving application of soap before high-pressure washing. Moreover, an improved cleanliness (significantly lower ATP values one hour after washing) was shown on plastic (PVC), cast-in-place concrete, pressed vibrated concrete, and cast-iron surfaces by using hot water, as compared to the same surfaces washed with cold water. Therefore, water temperature is a key parameter for improving the sanitary state of pig buildings while reducing water usage, which can have beneficial effects on animal health and important economic and environmental benefits for producers.

The improper management of wastewater over several decades through natural and human activities have led to the pollution of freshwater and groundwater resources. Conventional water purification methods such as reverse osmosis and ion exchange have often been limiting due to expense, inefficient, and poor recyclability. As a result, the development of low-cost and sustainable technologies is needed. One promising technology is that of novel nanomaterials which have emerged as a safe, fast, and effective alternative to traditional methods. Application in different research areas already demonstrate the ability of some metal nanoparticles to be used for their antibacterial properties against various microorganisms. This study has focused on metal oxide nanoparticles derived from magnetite (Fe3O4), which were synthesized de novo at room temperature and pressure from ferrous and ferric iron salt solutions using steady-state headspace NH3(g), without mechanical agitation to an average size of <20 nm. Magnetite nanoparticles were coated with tetraethyl orthosilicate (TEOS) and 3-aminopropyltriethoxysilane (APTES) to an average size of < 50 nm with optimization studies focusing on variations in concentration, ratio, temperature, and time. Size distributions and shape uniformity were based on enumeration of TEM images with chemical compositions analyzed by: XRD, EDXRF, and FT-IR. Antimicrobial studies were conducted to assess the bacterial inhibition and elimination ability of magnetite-based nanoparticles in wastewater. The results showed a log reduction in the CFU/mL of E.coli in water. Further studies will be presented to evaluate the minimum inhibitory concentrations, efficacy, and specificity of the nanoparticles for gram-positive and gram-negative bacterial strains.

The use of plastic film mulch can improve water use efficiency in horticultural crops and increase yields by retaining soil moisture, suppressing weeds, and increasing soil temperature. Over time, these plastics degrade to particles less than 5 mm in size (microplastics). There is concern that microplastics could be detrimental, but the effects of microplastics on soil properties and plant growth are not well understood. Two experiments were conducted to investigate the effects of two types of microplastics (low-density polyethylene (LDPE) and polylactide and polybutylene adipate-co-terephthalate (PLA+PBAT)) at three concentrations (0.5%, 1.0%, 1.5% w/w) on soil properties and the growth of tomatoes, and strawberry with a negative control. In the strawberry experiment, there was a significant interaction between the effects of microplastic type and concentration on soil pH and electrical conductivity (EC) (P<0.05 throughout). Soil pH was higher and EC lower in treatments with 1.5% PLA+PBAT compared to all other treatments. In the tomato experiment, microplastics did not significantly effect emergence rate, height, shoot biomass, or root biomass. Plants grown in soil with PLA+PBAT had significantly more leaves and higher chlorophyll concentrations. The higher number of leaves and concentration of chlorophyll in tomatoes grown in soil containing PLA+PBAT microplastics invite further investigation into the causal mechanisms. The potential effects of PLA+PBAT or similar polymers in the soil are interesting to growers, policy makers, and manufacturers of horticultural mulch films.