Effects of Large-Scale Flooding on Regeneration of Big-Leaf Mahogany in the Bolivian Amazon

Growth response by big-leaf mahogany (Swietenia macrophylla) advance seedling regeneration to overhead canopy release in southeast Pará, Brazil

“…Mahogany is commonly believed to rely on catastrophic disturbances such as hurricanes, fires, and floods for successful recruitment by seedlings into juvenile and adult size classes, implying rapid growth over prolonged periods in large, persistent canopy gaps (Lamb, 1966;Snook, 1996Snook, , 2003Gullison et al, 1996Gullison et al, , 2003. Evidence supporting the catastrophic disturbance paradigm is largely inferential, based on observations of adult population structures and spatial distribution patterns.…”

“…Lamb (1966) and Snook (1996Snook ( , 2003 report that mahogany trees survive hurricane winds and subsequent fires in Central America better than most tree species; Gullison et al (2003) found that mahogany survives flooding in lowland Bolivia at higher rates than other species. In Belize, Stevenson (1927) observed open gaps near mahogany seed trees dense with seedlings, with no regeneration in adjacent shaded forest understory.…”

River logjams cause frequent large-scale forest die-off events in southwestern Amazonia

“…The phenomena described by Gullison et al (1996) -formation of logjam, forest die-off, and transformation of forest into savannah -can be studied through the visual analysis of remote sensing imagery (Gullison et al, 2003). In this paper, rivers affected by logjam-induced floods have been identified by analyzing the changes in river path and vegetation cover visible on the time-lapse application of Google Earth Engine (https://earthengine.google.com/timelapse/).…”

“…Nevertheless, the observations of Gullison et al (1996) do suggest that logjams are an important factor driving forest disturbance and biodiversity patterns in the Bolivian Amazon. For example, it has been shown that the increase in light that follows forest die-off events caused by logjams creates optimal conditions for the regeneration of mahogany (Swietenia macrophylla King), influencing its population dynamics (Gullison et al, 2003;Snook, 1996). Gullison et al (1996) also reported the transformation of large areas of forest into savannah after being flooded.…”

Experimental establishment of big-leaf mahogany (Swietenia macrophylla King) seedlings on two soil types in native forest of Pará, Brazil

“…Small seedlings may succumb to inundation; however, once tall enough, they may gain a competitive advantage if standing waters eliminate shorter, heterospecific seedlings as well. Established mahogany seedlings have been shown to be favoured by episodic flooding in Bolivia, thereby enhancing the regeneration prospects of mahogany saplings (Gullison et al, 2003).…”