Historical range and variation (HRV)

Abstract

Many ecosystems and landscapes are experiencing rapid and potentially persistent changes as the result of complex and potentially novel interactions of anthropogenic climate changes; shifting fire regimes; exotic plant, insect, and pathogen invasions; and industrial, agricultural, and urban development (Moritz and Agudo 2013; Joyce et al. 2014; Bone et al. 2016; Kolb et al. 2016; Smith et al. 2016; Stephens et al. 2016; Schoennagel et al. 2017). In fire-prone, fire-adapted landscapes - those where fire is an integral part of ecosystem maintenance and functioning - anthropogenic actions can directly and indirectly influence fire regimes and fire effects via changes in vegetation distributions, fuel condition, and weather events that influence fire behavior (Loehman et al. 2014). Many of today’s landscapes are fully departed from historical conditions, and it is difficult to determine if they should be managed as novel environments or as landscapes in transition or under recovery. A benchmark representation of those conditions that describe fully functional, healthy ecosystems or landscapes is key to understanding disturbance impacts and implementing sound ecosystem management (Cissel et al. 1994; Laughlin et al. 2004; Wiens et al. 2012). This benchmark can provide an ecological reference against which contemporary conditions can be evaluated to determine status, trend, and magnitude of departure. These departures can then be used to (1) prioritize areas for possible treatment, (2) design feasible treatments for restoration, (3) develop monitoring plans to evaluate treatment results, and (4) identify drivers of change associated with ecosystem transitions (Aplet et al. 2000; Andersen et al. 2009; Alagona et al. 2012; Dickinson 2014). Because ecosystems are inherently dynamic (White and Pickett 1985; Mori 2011), it is critical that reference conditions capture natural variability over appropriate scales of time and space (Swanson et al. 1994).

Citation

Keane, Robert E.; Loehman, Rachel. 2019. Historical range and variation (HRV). In: Manzello, Samuel L., ed. Encyclopedia of Wildfires and Wildland-Urban Interface (WUI) Fires. Cham, Switzerland: Springer. 12 p.