Dataset Information

Plant-plant interactions as a mechanism structuring plant diversity in a Mediterranean semi-arid ecosystem.

ABSTRACT: Plant-plant interactions are among the fundamental processes that shape structure and functioning of arid and semi-arid plant communities. Despite the large amount of studies that have assessed the relationship between plant-plant interactions (i.e., facilitation and competition) and diversity, often researchers forget a third kind of interaction, known as allelopathy. We examined the effect of plant-plant interactions of three dominant species: the perennial grass Lygeum spartum, the allelopathic dwarf shrub Artemisia herba-alba, and the nurse shrub Salsola vermiculata, on plant diversity and species composition in a semi-arid ecosystem in NE Spain. Specifically, we quantified the interaction outcome (IO) based on species co-occurrence, we analyzed diversity by calculation of the individual species-area relationship (ISAR), and compositional changes by calculation of the Chao-Jaccard similarity index. We found that S. vermiculata had more positive IO values than L. spartum, and A. herba-alba had values between them. Lygeum spartum and A. herba-alba acted as diversity repellers, whereas S. vermiculata acted as a diversity accumulator. As aridity increased, A. herba-alba transitioned from diversity repeller to neutral and S. vermiculata transitioned from neutral to diversity accumulator, while L. spartum remained as diversity repeller. Artemisia herba-alba had more perennial grass species in its local neighborhood than expected by the null model, suggesting some tolerance of this group to its "chemical neighbor". Consequently, species that coexist with A. herba-alba were very similar among different A. herba-alba individuals. Our findings highlight the role of the nurse shrub S. vermiculata as ecosystem engineer, creating and maintaining patches of diversity, as well as the complex mechanism that an allelopathic plant may have on diversity and species assemblage. Further research is needed to determine the relative importance of allelopathy and competition in the overall interference of allelopathic plants.

SUBMITTER: Arroyo AI

PROVIDER: S-EPMC6102514 | biostudies-literature | 2015 Nov

REPOSITORIES: biostudies-literature

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Plant-plant interactions as a mechanism structuring plant diversity in a Mediterranean semi-arid ecosystem.

Arroyo Antonio I AI Pueyo Yolanda Y Saiz Hugo H Alados Concepción L CL

Ecology and evolution 20151028 22

Plant-plant interactions are among the fundamental processes that shape structure and functioning of arid and semi-arid plant communities. Despite the large amount of studies that have assessed the relationship between plant-plant interactions (i.e., facilitation and competition) and diversity, often researchers forget a third kind of interaction, known as allelopathy. We examined the effect of plant-plant interactions of three dominant species: the perennial grass <i>Lygeum spartum</i>, the all ...[more]

PMID: 30151133

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Project description:Predicting the capacity of ecosystems to absorb impacts from disturbance events (resilience), including land-use intensification and landscape fragmentation, is challenging in the face of global change. Little is known about the impacts of fragmentation on ecosystem functioning from a multi-dimensional perspective (multiple traits). This study used 58 500-m linear transects to quantify changes in the functional composition and resilience of vascular plant communities in response to an increase in landscape fragmentation in 18 natural scrubland fragments embedded within a matrix of abandoned crop fields in Cabo de Gata-Níjar Natural Park, Almería, Spain. Changes in functional community composition were measured using functional diversity indices (functional richness and functional dispersion) that were based on 12 plant traits. Resilience was evaluated using the functional redundancy and response diversity from the perspective of plant dispersal, which is important, particularly, in fragmented landscapes. Scrubland fragmentation was measured using the Integral Index of Connectivity (IIC). The functional richness of the plant communities was higher in the most fragmented scrubland. Conversely, the functional dispersion (i.e., spread) of trait values among species in the functional trait space was lower at the most fragmented sites; consequently, the ecological tolerance of the vegetation to scrubland fragmentation decreased. Classifying the plant species into four functional groups indicated that fragmentation favoured an increase in functional redundancy in the 'short basal annual forbs and perennial forbs' group, most of which are species adapted to degraded soils. An assessment based on the traits associated with plant dispersal indicated that the resilience of 'woody plants', an important component in the Mediterranean scrubland, and habitat fragmentation were negatively correlated; however, the correlation was positive in the 'short basal annual forbs and perennial forbs' and the 'grasses' groups.

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Dataset Information

Plant-plant interactions as a mechanism structuring plant diversity in a Mediterranean semi-arid ecosystem.

Publications

Plant-plant interactions as a mechanism structuring plant diversity in a Mediterranean semi-arid ecosystem.

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