0000000000888542
AUTHOR
Janne Soininen
Distance decay 2.0 – a global synthesis of taxonomic and functional turnover in ecological communities
AbstractUnderstanding the variation in community composition and species abundances, i.e., β-diversity, is at the heart of community ecology. A common approach to examine β-diversity is to evaluate directional turnover in community composition by measuring the decay in the similarity among pairs of communities along spatial or environmental distances. We provide the first global synthesis of taxonomic and functional distance decay along spatial and environmental distance by analysing 149 datasets comprising different types of organisms and environments. We modelled an exponential distance decay for each dataset using generalized linear models and extracted r2 and slope to analyse the streng…
Local environment and space drive multiple facets of stream macroinvertebrate beta diversity
AIM: Understanding variation in biodiversity typically requires consideration of factors operating at different spatial scales. Recently, ecologists and biogeographers have recognized the need of analysing ecological communities in the light of multiple facets including not only species‐level information but also functional and phylogenetic approaches to improve our understanding of the relative contribution of processes shaping biodiversity. Here, our aim was to disentangle the relative importance of environmental variables measured at multiple levels (i.e., local, catchment, climate, and spatial variables) influencing variation in macroinvertebrate beta diversity facets (i.e., species, tr…
Plant trait‐environment relationships in tundra are consistent across spatial scales
Patterns and processes shaping ecosystems vary across spatiotemporal scales. As plant functional traits reflect ecosystem properties, investigating their relationships with environment provides an important tool to understand and predict ecosystem structure and functioning. This is particularly important in the tundra where a changing climate may trigger severe alterations in plant communities as both summer and winter conditions are changing. Here, we investigate the relationships between key environmental drivers including summer temperature, snow persistence, topographic position and soil pH, and species height, specific leaf area (SLA) and seed mass as plant traits. The study is carried…
Does catchment geodiversity foster stream biodiversity?
Abstract Context One approach to maintain the resilience of biotic communities is to protect the variability of abiotic characteristics of Earth’s surface, i.e. geodiversity. In terrestrial environments, the relationship between geodiversity and biodiversity is well recognized. In streams, the abiotic properties of upstream catchments influence stream communities, but the relationships between catchment geodiversity and aquatic biodiversity have not been previously tested. Objectives The aim was to compare the effects of local environmental and catchment variables on stream biodiversity. We specifically explored the usefulness of catchment geodiversity in explaining the species richness on …
Does trait-based joint species distribution modelling reveal the signature of competition in stream macroinvertebrate communities?
1. The occupancy and abundance of species are jointly driven by local factors, such as environmental characteristics and biotic interactions, and regional‐scale factors, such as dispersal and climate. Recently, it has been shown that biotic interactions shape species occupancies and abundances beyond local extents. However, for small ectothermic animals, particularly for those occurring in freshwater environments, the importance of biotic interactions remains understudied. Species‐to‐species associations from joint species distribution models (i.e. species associations while controlling for environmental characteristics) are increasingly used to draw hypotheses of which species possibly sho…
Subtropical streams harbour higher genus richness and lower abundance of insects compared to boreal streams, but scale matters
Aim: Biological diversity typically varies between climatically different regions, and regions closer to the equator often support higher numbers of taxa than those closer to the poles. However, these trends have been assessed for a few organism groups, and the existing studies have rarely been based on extensive identical surveys in different climatic regions. Location: We conducted standardized surveys of wadeable streams in a boreal (western Finland) and a subtropical (south-eastern Brazil) region, sampling insects identically from 100 streams in each region and measuring the same environmental variables in both regions. Taxon: Aquatic insects. Methods: Comparisons were made at the scale…
Distance decay 2.0. A global synthesis of taxonomic and functional turnover in ecological communities
Caio Graco-Roza was funded by the Coordination for the Improvement of Higher Education Personnel (CAPES), the Carlos Chagas Filho Research Support Foundation (FAPERJ) and the Ella and Georg Erhnrooth Foundation; Jan Altman by research grants INTER-EXCELLENCE LTAUSA19137 provided by Czech Ministry of Education, Youth and Sports, 20-05840Y of the Czech Science Foundation, and long-term research development project no. RVO 67985939 of the Czech Academy of Sciences; Otso Ovaskainen was funded by Academy of Finland (grant no. 309581), Jane and Aatos Erkko Foundation, Research Council of Norway through its Centres of Excellence Funding Scheme (223257), and the European Research Council (ERC) unde…
Local eukaryotic and bacterial stream community assembly is shaped by regional land use effects
With anticipated expansion of agricultural areas for food production and increasing intensity of pressures stemming from land-use, it is critical to better understand how species respond to land-use change. This is particularly true for microbial communities which provide key ecosystem functions and display fastest responses to environmental change. However, regional land-use effects on local environmental conditions are often neglected, and, hence, underestimated when investigating community responses. Here we show that the effects stemming from agricultural and forested land use are strongest reflected in water conductivity, pH and phosphorus concentration, shaping microbial communities a…
Towards understanding the abundance of non-pollen palynomorphs : A comparison of fossil algae, algal pigments and sedaDNA from temperate lake sediments
Given the increased interest in non-pollen palynomorphs (microscopic objects other than pollen identified from pollen slides) in palaeoecological studies, it is necessary to seek a deeper understanding of the reliability of these results. We combined quantitative information of algal pigments and sedimentary ancient DNA (sedaDNA) of phylotaxonomical resolution to validate the richness and abundance of fossil algae in the sediment of a small temperate lake. For the first time, fossil and sedaDNA algae data were combined in a composite data-set and used to reconstruct algae turnover rates over the last 14,500 years. This comparison serves as both an example of howfossil algae can be used to a…
Community size affects the signals of ecological drift and niche selection on biodiversity
AbstractEcological drift can override the effects of deterministic niche selection on small populations and drive the assembly of small communities. We tested the hypothesis that smaller local communities are more dissimilar among each other because of ecological drift than larger communities, which are mainly structured by niche selection. We used a unique, comprehensive dataset on insect communities sampled identically in a total of 200 streams in climatically different regions (Brazil and Finland) that differ in community size by fivefold. Null models allowed us to estimate the magnitude to which beta diversity deviates from the expectation under a random assembly process while taking di…
Community size can affect the signals of ecological drift and niche selection on biodiversity
Made available in DSpace on 2020-12-12T01:24:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-06-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Academy of Finland Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Ecological drift can override the effects of deterministic niche selection on small populations and drive the assembly of some ecological communities. We tested this hypothesis with a unique data set sampled identically in 200 streams in two regions (tropical Brazil and boreal Finland) that differ in macroinvertebrate community size by fivefold. Null models allowed us t…
Beta diversity of stream insects differs between boreal and subtropical regions, but land use does not generally cause biotic homogenization
Made available in DSpace on 2021-06-25T10:17:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-03-01 Previous studies have found mixed results regarding the relationship between beta diversity and latitude. In addition, by influencing local environmental heterogeneity, land use maymodify spatial taxonomic and functional variability among communities causing biotic differentiation or homogenization. We tested 1) whether taxonomic and functional beta diversities among streams within watersheds differ between subtropical and boreal regions and 2) whether land use is related to taxonomic and functional beta diversities in both regions.Wesampled aquatic insects in 100 subtropical (Brazil…
Sampling effort and information quality provided by rare and common species in estimating assemblage structure
Made available in DSpace on 2020-12-12T01:06:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-03-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Academy of Finland Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Reliable biological assessments are essential to answer ecological and management questions but require well-designed studies and representative sample sizes. However, large sampling effort is rarely possible, because it demands large financial resources and time, restricting the number of sites sampled, the duration of the study and the sampling effort at each site. In…