This study investigated the relationship between nitrogen and carbon in the thalli of the lichen Evernia prunastri, with an emphasis on the role of the C/N balance in the response of this species to N excess. For this purpose, thalli collected at a remote site were sprayed for 5 weeks with NH4NO3 (0.05 and 1 M) and (NH4)2SO4 (0.025 and 0.5 M) solutions, and later analyzed for their C and N content. The results showed that the total N content of thalli increased and the total C content decreased along with increasing N concentration in the treatment solutions. Consequently, the C/N ratio also significantly decreased in treated samples. The Fv/Fm ratio, taken as a vitality index, turned out to be positively correlated with C content and negatively correlated with N content. It is suggested that N stress is caused by the lack of compensation for elevated ammonium levels with higher C assimilation. It is concluded that E. prunastri is a suitable bioindicator of N pollution and that the C/N ratio deserves further investigation as a promising tool for early warning of N excess.

Effect of nitrogen supply on the C:N balance in the lichen Evernia prunastri (L.) Ach

RENZI M;LOPPI S
2013

Abstract

This study investigated the relationship between nitrogen and carbon in the thalli of the lichen Evernia prunastri, with an emphasis on the role of the C/N balance in the response of this species to N excess. For this purpose, thalli collected at a remote site were sprayed for 5 weeks with NH4NO3 (0.05 and 1 M) and (NH4)2SO4 (0.025 and 0.5 M) solutions, and later analyzed for their C and N content. The results showed that the total N content of thalli increased and the total C content decreased along with increasing N concentration in the treatment solutions. Consequently, the C/N ratio also significantly decreased in treated samples. The Fv/Fm ratio, taken as a vitality index, turned out to be positively correlated with C content and negatively correlated with N content. It is suggested that N stress is caused by the lack of compensation for elevated ammonium levels with higher C assimilation. It is concluded that E. prunastri is a suitable bioindicator of N pollution and that the C/N ratio deserves further investigation as a promising tool for early warning of N excess.
Pubblicato
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11368/2963327
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 7
  • ???jsp.display-item.citation.isi??? 6
social impact