We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
The role of rare rainstorms in the formation of calcic soil horizons on alluvial surfaces in extreme deserts
- Authors
Amit, Rivka; Enzel, Yehouda; Grodek, Tamir; Crouvi, Onn; Porat, Naomi; Ayalon, Avner
- Abstract
Abstract: Soils in similar geomorphic settings in hyperarid deserts (<50mm yr−1) should have similar characteristics because a negative moisture balance controls their development. However, Reg soils in the hyperarid southern Negev and Namib deserts are distinctly different. Soils developed on stable alluvial surfaces with only direct input of rainfall and dust depend heavily on rainfall characteristics. Annual rainfall amount can be similar (15–30mm), but storm duration can drastically alter Reg soil properties in deserts. The cooler fall/winter and dry hot summers of the southern Negev Desert with a predominance brief (≤1day) rainstorms result in gypsic-saline soils without any calcic soil horizon. Although the Namib Desert receives only 50–60% of the southern Negev annual rainfall, its rainstorm duration is commonly 2–4days. This improves leaching of the top soil under even lower annual rainfall amount and results in weeks-long grass cover. The long-term cumulative effect of these rare rain-grass relationships produces a calcic-gypsic-saline soil. The development of these different kinds of desert soils highlights the importance of daily to seasonal rainfall characteristics in influencing soil-moisture regime in deserts, and has important implications for the use of key desert soil properties as proxies in paleoclimatology.
- Subjects
NAMIB Desert (Namibia); NAMIBIA; NEGEV (Israel); ISRAEL; RAINSTORMS; GEOLOGICAL formations; SOIL horizons; FLUVISOLS; GEOMORPHOLOGY; CARBONATES
- Publication
Quaternary Research, 2010, Vol 74, Issue 2, p177
- ISSN
0033-5894
- Publication type
Article
- DOI
10.1016/j.yqres.2010.06.001