Biology subjects

Martin-Fores, I.

Publications and source records attributed to Martin-Fores, I..

2 recordsLinked to original sources

bioRxiv2024

Detecting ecosystem trends in response to climate and disturbance across continental plot networks: a power analysis

Plant communities are dynamic: cyclical, directional and stochastic changes in species composition make interpretation of responses complex. The multi-dimensionality of ecological change is reduced by ecosystem indicators that quantify functional responses to environmental drivers. However, thresholds of detectable change in indicators may vary by ecosystem or the spatial configuration of monitoring sites within regions. We quantified the power of a continental terrestrial ecosystem plot network (TERN Ausplots, Australia) to detect change in ecological indicators linked to disturbance and climate: community temperature index (CTI), proportional abundance of photosynthetic pathways (C4%), and species abundance distribution (SAD). We simulated trend and noise scenarios and calculated power and effect size across spatial clusters of plots using linear mixed effects models. We then assessed factors that influenced change detection capacity. Power varied substantially across the network. Trends with a minimum magnitude of 0.5-3.0{degrees}C in CTI, 0.01-0.3 in C4% and 0.1-0.5 in the SAD sigma were detectable, depending on cluster identity and noise. Increased plot replication within a spatial cluster increased power and lower variance among baseline replicates increased effect size for CTI and C4% but not SAD. Latitudinal patterns in change detection capacity emerged for CTI and C4%. The effect size of increasing CTI was greater in the tropics due to lower among-plot variance, while power to detect increasing C4% was higher in the temperate south, where C4 is rare. Indicators reveal trends in complex ecological data that can inform decision-making. Increasing spatial replication and minimising spatial variation by stratifying plots to the same ecological community enhance change detection, albeit with different effectiveness by indicator. The results suggest change detection differs by location, irrespective of sampling factors such as number of plots. Strategies and thresholds for change detection may therefore apply unequally across environments and should be considered by region and response parameter.

ecology↗

bioRxiv2024

Land-use impacts on plant functional diversity throughout Europe

AimGlobal biodiversity loss resulting from anthropogenic land-use activities is a pressing concern, requiring precise assessments of impacts at large spatial extents. Existing models mainly focus on species richness and abundance, lacking insights into ecological mechanisms and species roles in ecosystem functioning. To bridge this gap, we conducted an extensive analysis of the impact of human land use on vascular plant functional diversity, across diverse land-use classes and bioregions in Europe, comparing it to traditional metrics. Location: Europe Time period: 1992-2019 Major taxa studied: Vascular plants MethodsIntegrating extensive databases of vegetation plots with spatial data on land use and land cover, we paired plots from areas actively used and modified by humans with plots from natural habitats under similar environmental conditions. Using species occurrences and traits, in each plot we computed three complementary functional diversity metrics (functional richness, evenness, and divergence), species richness and abundance. We assessed the impact of land use by comparing the metrics in the paired plots. ResultsOur findings revealed that, compared to natural habitats, anthropogenic land use exhibits lower functional richness and divergence but higher functional evenness across most land-use classes and bioregions. The response of functional richness was more marked than the other two metrics and especially pronounced in croplands and urban areas and in northern bioregions. Functional richness exhibited a pattern that did not fully overlap with the trend in species richness, providing useful complementary information. Main conclusionsWe provide a large-scale precise assessment of anthropogenic land-use impacts on functional diversity across Europe. Our findings indicate that: (i) human disturbance significantly alters plant functional diversity compared to natural habitats; (ii) this alteration goes in the direction of functional homogenization; (i) functional diversity metrics complement traditional metrics by offering deeper insights into the ecological mechanisms in response to anthropogenic land use.

ecology↗