Effects of Surface and Sub-Surface Soil Horizons on the Seasonal Performance of Larrea tridentata (Creosotebush)
Hamerlynck EP, McAuliffe JR, Smith SD. 2000. Effects of Surface and Sub-Surface Soil Horizons on the Seasonal Performance of Larrea tridentata (Creosotebush). Functional Ecology. 14(5):596-606
In warm arid and semiarid environments, the accumulation of clay minerals produces increasingly well developed soil horizons with the passage of time. Differences in the strength of development of two prominent soil horizons, silt- and clay-rich surface vesicular (Av), and clay-enriched subsurface argillic (Bt), may strongly influence the amount and seasonal continuity of plant-available water and the physiological activity of long-lived desert shrubs. Three sites were selected on an alluvial piedmont (bajada) in the Mojave Desert that varied in surface and subsurface horizon development. Seasonal water potential and gas-exchange responses of the evergreen desert shrub Larrea tridentata [DC.] Cov., and volumetric soil water content, were measured monthly in 1996 on three soils in order to test the hypothesis that desert pavements, Av and subsurface Bt horizons differentially affect the effectiveness and utilization of seasonal precipitation. The results show that subsurface and surficial soil horizon development differentially affects the seasonal availability of water for desert plants. During wetter parts of the season, subsurface horizons limit the degree of water availability, while surface soil characteristics have the greatest influence on the effectiveness of summer precipitation. These findings suggest that the effectiveness of climatic precipitation and attendant plant utilization of water resources in warm desert systems may depend on the physical soil condition.
- Type
- Journal Article
- Authors
- Hamerlynck, Erik; McAuliffe, Joseph; Smith, Stanley
- Units
- MOJA
- Keywords
- Absence (Biodiversity), Alluvial Fans, bajadas, Creosotebush), Larrea tridentata (Creosote Bush, Mojave Desert, Photosynthesis, Presence (Biodiversity), Sapindales, seasonal rainfall utilization, Soil Horizon, Soils, Taxa Links To References, Vascular Plant, water potential anomaly, Water Relations, Zygophyllaceae (Caltrop)