Ecohydrological niche segregation among coexisting C3 and C4 desert shrubs in a gypsum-calcareus formation (NW Iran)

Researcher: 
Ferrio Díaz, Juan Pedro
Congress: 
III Gypworld Workshop
Participation type: 
Comunicación oral
Other authors: 
de la Puente L, Rudov A, Palacio S, Sharifi A, Querejeta, JI, Ferrio JP, Akhani H
Year: 
2022
Location: 
Almería, Spain, 9-13 may 2022
Publication: 
Laura de la Puente (speaker), Alexander Rudov, Sara Palacio, Arash Sharifi, José Ignacio Querejeta, Juan Pedro Ferrio, Hossein Akhani (2022) Ecohydrological niche segregation among coexisting C3 and C4 desert shrubs in a gypsum-calcareous formation (NW Iran), III Gypworld Workshop, Almería, Spain, 9-13 may 2022

Xerophilic desert shrubs belong to multiple functional types and frequently show hydrological niche segregation. The understanding of water use in such co-occurring species is crucial to predict climate aridification impacts on desert ecosystems. This is in particular the case for the Irano−Turanian gypsum deserts - highly biodiverse but at the same time vulnerable and poorly studied ecosystems.
We aimed to unravel the ecohydrological strategies of five co-existing desert shrubs growing in gypsum deserts in NW Iran.
Soil and xylem sampling for isotope analyses was performed in spring and summer. Xylem and soil water extraction was performed by cryogenic vacuum distillation. Oxygen and hydrogen isotope composition were determined. Statistical analyses were run to determine the ecohydrological strategies of the investigated species.
Species-season interactions could explain differences in xylem sap isotopic composition. Plant gypsum affinity and photosynthetic pathways did not have a significant effect on the water use strategies. Three basic water use strategies relying on contrasting utilization of free topsoil moisture and deep soil water have been revealed in the different species.
Water use strategies in Iranian desert shrubs may vary dramatically even in closely related congeneric species. Further studies on the poorly studied xerophilic Irano−Turanian eudicots are necessary to fully understand their ecohydrological strategies.
Keywords
Caryophyllales, desert shrubs, gypsum, Iran, niche segregation, stable isotopes, water use.