A network of time lapse cameras for monitoring forest plant phenology

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Environmental change such as climate warming can have a major impact on the timing of annual events in the life of a plant, such as leaf-out or flowering, which in turn have important consequences for plant fitness and interactions with other species. Climate warming, for example, often causes earlier flowering, but the particular climate variables involved remain poorly understood, and the question of whether warming might cause gene flow among populations (e.g. at different elevations) to increase or decrease (via increasingly convergent or divergent flowering times) is unknown. In forest ecosystems, the relative timing of leaf emergence in understory plants relative to the tree canopy can have a huge impact on the period of high light in spring, and therefore on carbon gain, but it is unclear to what degree leaf emergence in the understory vs. canopy respond differentially to warming. Answering these questions, and many others, requires simple but time-consuming observations, not only at a high frequency within a given growing season, but also over many years and in many plots. Such data sets are exceedingly rare, with even the best-known cases typically including only first flower dates rather than the entire yearly flowering schedule. 2016 will mark the fourth year of flowering phenology observations in a set of 12 long-term monitoring plots along an elevational gradient in Parc national du Mont Mégantic, Québec, where vegetation transitions from temperate deciduous forest at low elevation to coniferous boreal forest at high elevation. Here I propose to install a network of time-lapse cameras at these sites in order to: (1) increase the frequency of observations to allow calibration of our statistical methods, which use data collected on 3-4 day intervals, (2) permit a relatively inexpensive means (in terms of operational costs) of ensuring continual long-term data, and (3) launch long-term observations of the timing of leaf-out in the understory vs. the canopy. Our phenological observations to date have been labour-intensive, and have thus focused only on flowering time. The resulting data from this research will provide both a means of testing key questions concerning the causes and consequences of changes in phenology (see above), and provide the foundation for more focused experiments and observational studies on this topic over many years.