Background: what you need to know
WHAT IS THE PROBLEM?
Linear corridors resulting from oil and gas exploration are becoming an increasingly common disturbance in the boreal forests of Alberta. Seismic lines are linear corridors of cleared forest that allow for the profiling of oil and gas formations below ground (Machtans, 2006). There are two types of exploratory linear disturbances, the traditional wide 2D seismic lines and the narrower, high density 3D seismic lines. Studies looking at threshold levels of line width reveal that 2D seismic lines may have a greater ecological impact than narrower 3D lines (Bayne et. al. 2012). The average linear density of all seismic lines in northeast Alberta is reported at 1.5 km/km2, with some townships reach densities of 10 km/ km2 (Lee & Boutin, 2006). While some recovery of seismic lines has occurred, it is estimated that 35 years after clearing 60% of lines still have not regenerated (Lee & Boutin, 2006). |
WHY IS THIS A PROBLEM?
As these disturbances become persistent features on the landscape they can have adverse effects on wildlife and their habitat. Open corridors can expose the forest to edge effects and habitat fragmentation (Linke et al., 2008). Studies have shown that boreal-specialists such as ovenbirds (Bayne et al. 2005, 2006, Machtans 2006) and marten (Bayne et al., 2006) are susceptible to this degradation of habitat. Forest fragmentation due to seismic lines can lead to the invasion of non-native species into the forest interior and alteration of predator-prey dynamics, such as wolf-caribou (James & Stuart-Smith 2000, Dyer et al. 2002). From an economic standpoint, there is an estimated $37.5 billion (CAD) across all products extracted from the Canadian boreal forest annually (Sanderson et al. 2012). The fragmentation of forests due to increasing trends of oil and gas exploration affects the economic production of timber, an important industry in the province. Linear corridors open the forest interior to further disturbance from paths, ATV’s, and trucks. This continued disturbance likely has an effect on recovery rate of forests corridors. |
WHAT CAN BE DONE?
Following disturbance, a forest can proceed to a number of different successional trajectories that may or may not
resemble the original stand. In many instances, forest succession of seismic lines remains in a non-recovering stable
state referred to as arrested succession. It may take considerable funding and many years to ever recover sites experiencing arrested sucession. If we are to restore the natural structure and function of Alberta’s boreal forests, it is necessary to understand why and where arrested succession occurs.
objectives:
My project aims to identify which factors are most important in predicting the successional trajectory of the forest after linear disturbance (i.e. seismic line). Little is known about how site, stand and landscape factors interact to create differential patterns of successional trajectories. Restoration can be costly and time consuming, and it is not realistic that every seismic line be restored at once. I aim to develop a conceptual model for land planners and managers to use to predict where restoration efforts will have the most success. Restoration support should ideally be on lines that will not regenerate naturally on their own, but on the other hand, will have a successful chance for recovery.
I hypothesize that natural recovery will mostly determined by sites experiencing increased availability of nutrients and moisture that are contained within stands with low frequency of disturbance and fast-growing tree species (Aspen, Poplar and Pine).
If land and wildlife planners are to successfully restore and prioritize conservation of linear corridors in the future, it will be necessary to know which factors have the greatest role in recovery and how they interact.
I hypothesize that natural recovery will mostly determined by sites experiencing increased availability of nutrients and moisture that are contained within stands with low frequency of disturbance and fast-growing tree species (Aspen, Poplar and Pine).
If land and wildlife planners are to successfully restore and prioritize conservation of linear corridors in the future, it will be necessary to know which factors have the greatest role in recovery and how they interact.