The role of leaf inclination, leaf orientation and plant canopy architecture in soil particle detachment by raindrops

Abstract

A laboratory investigation of the effect of plant architecture on soil particle detachment by rainfall is described. The effects of leaf inclination, leaf orientation, effective canopy area, leaf area index, leaf subcatchment area, lowest canopy area, largest canopy area, canopy overlap area and an alternative leaf area index are examined using artificial plants. Detachment from a 30 cm diameter splash cup filled with sand (150 µ µ µ µ µm-1 mm particle size) was measured under three types of plant (small leaved, broad leaved and long narrow leaved) for a 10 minute simulated rainstorm of 75 mm/h intensity. There were no significant differences in soil particle detachment between the three plant types or between detachment under the plants and detachment of bare soil. No significant relationships were obtained between detachment and any of the plant parameters. Soil particle detachment by leaf drips can offset any protective effects of the canopy so that detachment does not differ significantly from that on bare soil. Plant architecture significantly affected the distance from the plant stem at which detachment was concentrated even though the canopy diameters of the plants were similar. There would appear to be no advantages in a detailed description of plant architecture and its effects in process-based models of soil erosion. Parameters such as plant height and plant canopy area are sufficient descriptors for modelling plant effects.

Throughfall kinetic energy in young subtropical forests: Investigation on tree species richness effects and spatial variability

“…In such young forest stands horizontal tree characteristics seem to be of greater influence than vertical ones. This finding can support the key role of raindrop mass for rainfall erosivity over raindrop velocity being very low for small trees (Foot and Morgan, 2005;Goebes et al, 2014). Below small trees, however, small raindrop sizes can reach terminal velocity (de Moraes Frasson and Krajewski, 2011).…”

Stemflow on the woody parts of plants: dependence on rainfall intensity and event profile from laboratory simulations

“…In this way, the impact speed and energy of the droplets impinging on the branches were reduced. Additionally, a wider spread of drop sizes is generated by the use of a screen, and drops are prevented from landing at the same locations below the drop‐formers (Imeson, ; Holden and Burt, ; Foot and Morgan, ; Clarke and Walsh, ). This modification of the experimental protocol was designed to suggest how stemflow generation might be affected by the presence of foliage, which also reduces the impact energy of drops on the branches sheltered below.…”

Quantification of runoff generation from a combined glacier and <i>páramo</i> catchment within an Ecological Reserve in the Ecuadorian highlands

“…Although, this additional source of water is minor and mostly intercepted by 15 arbustive vegetation (Chuquiraga), other studies (Crockford and Richardson, 2000;Foot and Morgan, 2005) showed that the páramo ecosystem can catch low energy rain, drizzle and fog moisture on their leaves, which conduct over 50% of rainwater directly to the volcanic ash soils of Ecuadorian highlands (Janeau et al, 2015).…”