Stemflow

In tropical rainforests, where this kind of flow can be substantial, erosion gullies can form at the base of the trunk.

The most common direct measurement currently used is the bonding of bisected PVC or other plastic tubing around the circumference of the tree trunk, connected and funneled into a graduated cylinder for manual or a tipping bucket rain gauge for automatic collection.

The particular morphological characteristics that are key factors are: Stand characteristics In addition to the effects of individual tree species, the overall structure of the forest stand also influences the amount of stemflow that will ultimately occur, these factors are:[3] Other Chemistry Nutrients that have accumulated on the canopy from dry deposition or animal feces are able to directly enter the soil through stemflow.

Conversely, nutrients are taken up by the tree when concentration is lower in the canopy than the rainfall, the presence of epiphytes or lichens also contributes to uptake.

The nutrients that enter the soil can also reflect the particular environmental conditions around them, for example, plants located in industrialized areas exhibit higher rates of sulfur and nitrogen (from air pollution), whereas those located near the oceans have higher rates of sodium (from seawater).