Treefall gap

A treefall gap is a distinguishable hole in the canopy of a forest with vertical sides extending through all levels down to an average height of 2 m (6.6 ft) above ground.

The ecologist who developed this definition used two meters because he believed that "a regrowth height of 2 m was sufficient" for a gap to be considered closed, but not all scientists agree.

[3] Tree falls are commonly caused by old age, natural hazards, or parasitic plants (or certain epiphytes).

[2] Commonly, however, the gap is irregularly shaped and must be divided into smaller sections to be measured individually in order to obtain higher accuracy.

[2] This method provides a more accurate measurement as it takes into account differences in structure of the gap descending from the canopy to the forest floor.

[citation needed] A study conducted on Barro Colorado Island found that lianas play a likely role in slowing gap-regeneration time.

[6] IDH helps explain the Gap Hypothesis which postulates that more light and more diverse resources caused by the falling of a canopy tree may aid in more species abundance.

The creation of a treefall gap causes a break in the canopy to form, allowing light to penetrate through to the understory.

[8] Seed dispersal in treefall gaps is significantly reduced compared to normal understory areas.

[7] It is proposed that treefall gaps maintain plant species diversity in tropical forests in three main ways.

[4] Being in an area that contains a high amount of light allows species that cannot grow in total or partial shade to develop rapidly.

Second, species may be able to survive on resources that spread from the middle of the gap all the way to the surrounding denser forest.

[9] There have been studies that show a noticeable difference in the species diversity of butterflies in treefall gaps and those in the surrounding understory.

The types of vegetation present in the gaps play a key role in determining which species of butterfly live there.

[10] Large-scale blow-downs of trees are generally caused by squall lines or tornadoes generating strong winds.

In some instances Global Positioning Systems (GPS) are used to map the centers of treefall gaps in order to determine their frequency.

[14] With satellite imaging, steps have to be implemented to remove extraneous details such as seas, rivers, clouds, etc.