Alec Downey

The tree nursery industry is the largest water consumer in the ornamental horticulture sector in Canada. In most nurseries, subjective irrigation scheduling protocols have conditioned the trees to receive daily irrigation, however, rising environmental concerns and cost of water have prompted the industry to reduce its use of water. These water sav...

Extensive research has found that nighttime transpiration (En) is positively correlated to the vapour pressure deficit (VPD), that suggested En was highest during the night under high temperatures and low humidity along with high soil water availability, typically for the riparian forest in the extreme arid region of China. This study used the heat...

Extensive research has found that nighttime transpiration (E n) is positively correlated to the vapour pressure deficit (VPD), that suggested E n was highest during the night under high temperatures and low humidity similarly to our site. This study used the heat ratio method to measure mature and sapling Populus euphratica sap velocity (V s), and...

Conventional irrigation practices are based on physical factors and observations, however this fails to include plant water status measurements. This study examined the relationship between cumulative water potential with concurrent cumulative vapour pressure deficit (VPD) for the common nursery species Thuja occidentalis 'Smaragd' (emerald pyramid...

Symmetrical temperature difference also known as the sap flow index (SFI) forms the basis of the Heat Field Deformation sap flow measurement and is simultaneously collected whilst measuring the sap flow. SFI can also be measured by any sap flow method applying internal continuous heating through the additional installation of an axial differential...

High mortality rates among most species of nursery trees after transplanting is generally attributed to water stress imposed by a range of soil and other environmental conditions. This study examined the efficacy of a consortium of mycorrhizae (Root Rescue Landscape Powder), comprised of 20 species of both endo-And ecto-mycorrhizae, in mitigating w...

Boreal forests occupy latitudes that are expected to warm most dramatically over the coming decades, and evidence indicates that changes are already underway in these systems. Much of the boreal is underlain by permafrost, which can be expected have important consequences for boreal forests as the climate warms. The southern margin of permafrost is...

While natural spatial temperature gradients between measurement needles have been thoroughly investigated for continuous heat-based sap flow methods, little attention has been given to how natural changes in stem temperature impact heat pulse-based methods through temporal rather than spatial effects. By modelling the theoretical equation for both...

Background / Purpose: The main drawback of traditional methods to measure embolism has been that they are destructive and labor-intensive. Stems have to be cut and hydraulic conductance measured, then stems have to be hydrated to remove emboli, and then re-measured to determine maximum hydraulic conductance. The objective of this research was to...