Publication Date:
2019
Description:
〈span〉Hillslopes constitute the majority of Earth’s land surface area and dominate the supply of sediment to rivers. Hillslope sediment transport is commonly modeled with a rate law that depends on slope and a rate coefficient, 〈span〉D〈/span〉, that is understood to represent the intensity of transport mechanisms. Although many transport mechanisms are related to water and biota, it is unclear whether 〈span〉D〈/span〉 varies predictably with climate and life. We compiled previous estimates of 〈span〉D〈/span〉 from around the world and also made new estimates for additional sites. The compilation reveals an overall trend in which 〈span〉D〈/span〉 increases strongly with increasing moisture among relatively dry sites and less strongly with increasing moisture among relatively wet sites. Vegetation type has a secondary effect on 〈span〉D〈/span〉 among drier sites, with 〈span〉D〈/span〉 increasing from deserts to grasslands to forests, but not among wetter sites. These trends suggest that the establishment of life in a landscape substantially accelerates soil creep, whereas differences in biological communities among sites with abundant moisture have a relatively small effect on creep.〈/span〉
Print ISSN:
0091-7613
Electronic ISSN:
1943-2682
Topics:
Geosciences
