Ecologically dominant species often define ecosystem states, but as human disturbances intensify, their subordinate counterparts increasingly displace them. We consider the duality of disturbance by examining how environmental drivers can simultaneously act as a stressor to dominant species and as a resource to subordinates. Using a model ecosystem, we demonstrate that CO2-driven interactions between species can account for such reversals in dominance; i.e., the displacement of dominants (kelp forests) by subordinates (turf algae). We established that CO2 enrichment had a direct positive effect on productivity of turfs, but a negligible effect on kelp. CO2 enrichment further suppressed the abundance and feeding rate of the primary grazer of turfs (sea urchins), but had an opposite effect on the minor grazer (gastropods). Thus, boosted production of subordinate producers, exacerbated by a net reduction in its consumption by primary grazers, accounts for community change (i.e., turf displacing kelp). Ecosystem collapse, therefore, is more likely when resource enrichment alters competitive dominance of producers, and consumers fail to compensate. By recognizing such duality in the responses of interacting species to disturbance, which may stabilize or exacerbate change, we can begin to understand how intensifying human disturbances determine whether or not ecosystems undergo phase shifts.

Connell S.D., Doubleday Z.A., Foster N.R., Hamlyn S.B., Harley C.D.G., Helmuth B., et al. (2018). The duality of ocean acidification as a resource and a stressor. ECOLOGY, 99(5), 1005-1010 [10.1002/ecy.2209].

The duality of ocean acidification as a resource and a stressor

Sarà Gianluca
Membro del Collaboration Group
;
2018

Abstract

Ecologically dominant species often define ecosystem states, but as human disturbances intensify, their subordinate counterparts increasingly displace them. We consider the duality of disturbance by examining how environmental drivers can simultaneously act as a stressor to dominant species and as a resource to subordinates. Using a model ecosystem, we demonstrate that CO2-driven interactions between species can account for such reversals in dominance; i.e., the displacement of dominants (kelp forests) by subordinates (turf algae). We established that CO2 enrichment had a direct positive effect on productivity of turfs, but a negligible effect on kelp. CO2 enrichment further suppressed the abundance and feeding rate of the primary grazer of turfs (sea urchins), but had an opposite effect on the minor grazer (gastropods). Thus, boosted production of subordinate producers, exacerbated by a net reduction in its consumption by primary grazers, accounts for community change (i.e., turf displacing kelp). Ecosystem collapse, therefore, is more likely when resource enrichment alters competitive dominance of producers, and consumers fail to compensate. By recognizing such duality in the responses of interacting species to disturbance, which may stabilize or exacerbate change, we can begin to understand how intensifying human disturbances determine whether or not ecosystems undergo phase shifts.
Settore BIO/07 - Ecologia
https://esajournals.onlinelibrary.wiley.com/doi/10.1002/ecy.2209
Connell S.D., Doubleday Z.A., Foster N.R., Hamlyn S.B., Harley C.D.G., Helmuth B., et al. (2018). The duality of ocean acidification as a resource and a stressor. ECOLOGY, 99(5), 1005-1010 [10.1002/ecy.2209].
File in questo prodotto:
File Dimensione Formato  
Connel et al 2018 Ecology.pdf

accesso aperto

Descrizione: Connell et al 2018 ECOLOGY
Tipologia: Versione Editoriale
Dimensione 912.11 kB
Formato Adobe PDF
912.11 kB Adobe PDF Visualizza/Apri

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: http://hdl.handle.net/10447/485035
Citazioni
  • ???jsp.display-item.citation.pmc??? 12
  • Scopus 42
  • ???jsp.display-item.citation.isi??? 41
social impact