The Biodiversity-Ecosystem Function hypothesis postulates that higher biodiversity is correlated with faster ecosystem process rates and increased ecosystem stability in fluctuating environments. Exhibiting high spatio-temporal habitat diversity, floodplains are highly productive ecosystems, supporting communities that are naturally resilient and highly diverse.
We examined linkages among floodplain wetland habitats, invertebrate communities and their associated traits, and ecosystem function across 60 sites within the floodplain wetlands of the lower Wolastoq | Saint John River, New Brunswick, using structural equation modelling and Threshold Indicator Taxa ANalysis (TITAN2).
We identified key environmental filters structuring invertebrate communities, by linking increased niche differentiation through shoreline change, flood pulse dynamics, and macrophyte bed complexity with increased taxa and functional diversity.
Examination of traits linked to ecosystem functions revealed that more resilient wetlands with balance between primary productivity and decomposition as carbon sources were associated with greater functional evenness and richness, while habitat patches with elevated decomposition rates had lower functional richness, reflecting a simplified, more disturbed habitat.
While our more complex overarching SEM model was ultimately compromised by an overspecified number of pathways, our results nevertheless are indicative of a divergence between wetland and riverine ecosystems in their relationships linking biodiversity and ecosystem function, illustrating how to define ecosystem health in wetland habitats, and demonstrating how critical functions support healthy wetland habitats by providing increased resilience to disturbance.
For specific methods, see the associated paper Rideout et al 2022, Functional Ecology
Rideout, N.K. (2020). nata1iekat/GLM_invertebrate_traits_v1:GLM_invertebrate_traits_v1 (Version v1.0.0) [Dataset]. Zonodo. http://doi.org/10.5281/zenodo.3948516
Raw sequence data has been deposited to the National Centre for Biotechnology Information (NCBI) Short Read Archive (SRA) under BioProjectID PRJNA640405.
The bioinformatic pipeline used to process COI metabarcodes is available from GitHub at https://github.com/Hajibabaei-Lab/SCVUC_COI_metabarcode_pipeline.
The COI Classifier used to make taxonomic assignments is also available from GitHub at https://github.com/terrimporter/CO1Classifier.
Natural Sciences and Engineering Research Council of Canada Collaborative Research and Development Grant, Award: NSERC CRD CRDPJ 462708-13
Natural Sciences and Engineering Research Council
Canadian Federal Genomics Research & Development Initiative’s Strategic Application of Genomics in the Environment (STAGE) program from Environment and Climate Change Canada