Differential nitrogen cycling in semiarid sub-shrubs with contrasting leaf habit
Resumen: Nitrogen (N) is, after water, the most limiting resource in semiarid ecosystems. However, knowledge on the N cycling ability of semiarid woody plants is still very rudimentary. This study analyzed the seasonal change in the N concentrations and pools of the leaves and woody organs of two species of semiarid sub-shrubs with contrasting leaf habit. The ability of both species to uptake, remobilize and recycle N, plus the main storage organ for N during summer drought were evaluated. We combined an observational approach in the field with experimental 15N labelling of adult individuals grown in sand culture. Seasonal patterns of N concentrations were different between species and organs and foliar N concentrations of the summer deciduous Lepidium subulatum were almost double those of the evergreen Linum suffruticosum. L. subulatum up took ca. 60% more external N than the evergreen and it also had a higher N resorption efficiency and proficiency. Contrastingly, L. suffruticosum relied more on internal N remobilization for shoot growth. Differently to temperate species, the evergreen stored N preferentially in the main stem and old trunks, while the summer deciduous stored it in the foliage and young stems. The higher ability of L. subulatum to uptake external N can be related to its ability to perform opportunistic growth and exploit the sporadic pulses of N typical of semiarid ecosystems. Such ability may also explain its high foliar N concentrations and its preferential storage of N in leaves and young stems. Finally, L. suffruticosum had a lower ability to recycle N during leaf senescence. These strategies contrast with those of evergreen and deciduous species from temperate and boreal areas, highlighting the need of further studies on semiarid and arid plants.
Idioma: Inglés
DOI: 10.1371/journal.pone.0093184
Año: 2014
Publicado en: PLoS One 9, 3 (2014), e93184 [9 pp]
ISSN: 1932-6203

Factor impacto JCR: 3.234 (2014)
Categ. JCR: MULTIDISCIPLINARY SCIENCES rank: 9 / 57 = 0.158 (2014) - Q1 - T1
Financiación: info:eu-repo/grantAgreement/ES/DGA/GA-LC-011-2008
Financiación: info:eu-repo/grantAgreement/ES/MINECO/CGL2011-26654
Tipo y forma: Article (Published version)

Creative Commons You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.


Exportado de SIDERAL (2017-11-28-13:51:57)

Este artículo se encuentra en las siguientes colecciones:
Articles



 Record created 2017-11-28, last modified 2017-11-29


Versión publicada:
 PDF
Rate this document:

Rate this document:
1
2
3
 
(Not yet reviewed)