Naslov
Linking disturbance and resistance via changes in biodiversity: a conceptual model and an experimental test on rocky reefs

Autori
Bulleri, Fabio ; Benedetti-Cecchi, Lisandro ; Jaklin, Andrej ; Iveša, Ljiljana

Izvornik
Ecology and Evolution (2045-7758) 6 (2016), 7; 2010-2021

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
biodiversity ; biological invasions ; Biotic Resistance Hypothesis ; canopy-formers ; Caulerpa cylindracea ; disturbance ; habitat-formers ; Intermediate Disturbance Hypothesis ; seaweeds

Sažetak
1. Biological invasions threaten biodiversity worldwide. Nonetheless, a unified theory linking disturbance and resistance to invasion through a mechanistic understanding of the changes caused to biodiversity is elusive. Building on different forms of the disturbance-biodiversity relationship and on the Biotic Resistance Hypothesis (BRH), we constructed conceptual models showing that, according to the main biodiversity mechanism generating invasion resistance (species richness vs identity), disturbance can either promote or hinder invasion. 2. Following the Intermediate Disturbance Hypothesis, a moderate intensity disturbance is expected to enhance species richness. This will promote invasion resistance when complementarity is more important than species identity. Negative effects of severe disturbance on invasion resistance, due to reductions in species richness, can be either overcompensated or exacerbated by species identity effects, depending on the life-traits becoming dominant within the native species pool. Different invasion resistance scenarios are generated when the diversity - disturbance relationship is negative or positive monotonic. 3. Predictions from this model were experimentally tested on rocky reefs. Macroalgal canopies differing in species richness (1vs2vs3) and identity, were exposed to either a moderate or a severe pulse disturbance. The effects of different canopy-forming species on the seaweed, Caulerpa cylindracea, varied from positive (Cystoseira crinita) to neutral (Cystoseira barbata) to negative (Cystoseira compressa). After two years, severely disturbed plots were monopolized by C. compressa and supported less C. cylindracea. 4. Our study shows that the effects of disturbance on invasion depend upon its intensity, the main mechanism through which biodiversity generates invasion resistance and the life-traits selected within the native species pool. Disturbance can sustain invasion resistance when promoting the dominance of competitively subordinate species possessing traits that allow outperforming invaders.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

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