A review of the intact forest landscape concept in the Canadian boreal forest: its history, value, and measurement

Abstract

Loss of global forest, and in particular forest that has little human disturbance, is a standard against which we measure progress to conserve Earth’s forests. The value of intact forest landscapes has taken hold in the global psyche. We provide a brief history of the intact forest landscape concept and discuss how this has moved to an operational definition used as a global and regional metric of forest conservation. We distinguish between a conceptual intact forest landscape and an operational definition. For the purposes of this paper we will use the term IFL to mean the operational definition and intact forest landscapes to mean the conceptual idea. We provide an overview of the science that supports the value of intact forest landscapes in a Canadian boreal context and analyse issues with using a standard operationalized IFL definition to both measure and promote conservation of forests at global and regional scales. We found many arguments for protecting large, intact forest landscapes that are relevant to the Canadian boreal forest, including conservation of biodiversity, ecological processes and ecosystem services, existence values, application of the precautionary principle, and the need for scientific benchmarks. But it is clear that the standard operational IFL size threshold of 50 000 ha in the boreal forest is inadequate to meet these broad conservation objectives. However, the concept of intact forest being large enough to allow for all natural processes and biodiversity is likely not logistically feasible in Canada’s managed boreal forest. The scale at which the most extensive processes (e.g., fire and insects) occur and species (e.g., woodland caribou) function is likely too large. Management options incorporating local knowledge of conservation needs and the specifics of ecosystem function and composition are more likely to be effective in conservation than rigid IFL requirements. A standardized approach is useful for global tracking of IFLs but it is not the best approach to meet more regional forest conservation goals. Intact forest landscapes have exceptional value but should be managed in the context of integrated land use planning that includes protected areas, sustainable forest management, species at risk management, and ecosystem restoration.

The State of Conservation in North America’s Boreal Forest: Issues and Opportunities

“…North America's Boreal Forest biome (Figure 2) is one of the most intact of these global forested ecosystems (Lee et al, 2003Andrew et al, 2012Andrew et al, , 2014Dinerstein et al, 2017;Venier et al, 2018). The biome is estimated to harbor 25% of the world's remaining intact forests (Aksenov et al, 2002;Lee et al, 2003.…”

“…With the advent of GIS capabilities and the availability of complete global coverage of remote sensing products over the last two decades, identification of the biomes of the world with the least large-scale human impacts has become possible. Notwithstanding the various methodological and definitional questions around how to define and map such areas (Potapov et al, 2017;Venier et al, 2018;Watson et al, 2018) there has been broad consensus that there are five regions of the world that encompass the largest areal extent of forest habitat that has not been subject to large-scale industrial logging, roadbuilding, mining, or other modern industrial land-use impacts. First identified in 1997 (Bryant et al, 1997) and termed "frontier forests" these forest areas have subsequently been mapped under different criteria and terms including "wilderness, " "intact forest" and "primary forest" in a number of other publications and analyses (Sanderson et al, 2002;Mittermeir et al, 2003;Potapov et al, 2008Potapov et al, , 2017Hansen et al, 2013;Mackey et al, 2014;Watson et al, 2016Watson et al, , 2018Dinerstein et al, 2017).…”

Linking radial growth patterns and moderate‐severity disturbance dynamics in boreal old‐growth forests driven by recurrent insect outbreaks: A tale of opportunities, successes, and failures

“…The success in achieving conservation objectives related to old‐growth forests depends heavily, however, on fine‐ and multiscale (i.e., at the tree, stand, and landscape scales) knowledge of the dynamics of these ecosystems. Inappropriate management practices, based on superficial knowledge and/or simplification of natural dynamics, may produce limited and even no ecological benefits (Fenton et al., 2013; Puettmann et al., 2009; Venier et al., 2018).…”

“…Inappropriate management practices, based on superficial knowledge and/or simplification of natural dynamics, may produce limited and even no ecological benefits (Fenton et al, 2013;Puettmann et al, 2009;Venier et al, 2018).…”

Are We Capturing Faunal Intactness? A Comparison of Intact Forest Landscapes and the “Last of the Wild in Each Ecoregion”

“…The methodology identifies large undeveloped forest areas through satellite-based mapping of tree canopy cover, with areas unfragmented by roads or other development of no smaller than 500 km 2 , assumed to be large enough to "maintain all native biodiversity, including viable populations of wideranging species" (Potapov et al, 2008(Potapov et al, , 2009. This size threshold was developed to be globally generalizable, but has been critiqued for being arbitrary and without scientific basis with respect to meeting biotic expectations, given the space needs of many wideranging species (Venier et al, 2018).…”