Benthic diatom communities in boreal streams: community structure in relation to environmental and spatial gradients

AbstractDisturbance events to coastal habitats such as extreme heat events, storms, or floods have increased in magnitude and frequency in recent years due to anthropogenic climate change and the destruction of habitats. These events constitute a major threat to many ecological communities and global biodiversity. Disturbance history influences ecosystem response to novel disturbances such that communities that have previously been exposed to disturbances should be more resilient to new disturbances compared to previously sheltered communities. This principle is defined as ecological memory. Resilience should also increase with access to a larger species pool, because a larger species pool increases species and response diversity of a community. One possibility of increasing the local species pool is connectivity via adequate dispersal between habitat patches with different species compositions in metacommunities. In a laboratory experiment, we exposed benthic diatom communities of different origin to a mechanical disturbance, simulated dispersal in half of the communities, and measured their chlorophyll a concentration over time. The local diatom communities originated from different locations on an intertidal flat that varied in hydrodynamic exposure history. Hydrodynamic exposure disturbs the sediment, and thereby determines sediment properties and the composition of intertidal diatom communities. In the experiment, disturbance negatively affected chlorophyll a concentration across all treatments. However, the response to disturbance depended on the ecological memory of the communities; the more exposed areas the communities originated from, the less negative was the effect of the mechanical disturbance. Interestingly, dispersal did not mitigate the negative impacts of disturbance in any of the communities. Our results highlight the importance of ecological memory for ecosystem functioning and demonstrate the limitations of patch connectivity to alleviate the impacts of disturbance events in metacommunities.

Download Full-text

Stable Seasonal and Annual Alpha Diversity of Benthic Diatom Communities Despite Changing Community Composition

Frontiers in Marine Science ◽

10.3389/fmars.2020.00088 ◽

2020 ◽

Vol 7 ◽

Author(s):

Leena Virta ◽

Janne Soininen ◽

Alf Norkko

Keyword(s):

Community Composition ◽

Alpha Diversity ◽

Benthic Diatom ◽

Diatom Communities

Download Full-text

Assessing anthropogenic pressures on streams: A random forest approach based on benthic diatom communities

The Science of The Total Environment ◽

10.1016/j.scitotenv.2017.02.096 ◽

2017 ◽

Vol 586 ◽

pp. 1101-1112 ◽

Cited By ~ 19

Author(s):

Floriane Larras ◽

Romain Coulaud ◽

Edwige Gautreau ◽

Elise Billoir ◽

Juliette Rosebery ◽

...

Keyword(s):

Random Forest ◽

Benthic Diatom ◽

Anthropogenic Pressures ◽

Diatom Communities

Download Full-text

An exploratory study of benthic diatom communities in stormwater ponds of different land uses and varying biocide contamination

Aquatic Ecology ◽

10.1007/s10452-020-09773-x ◽

2020 ◽

Vol 54 (3) ◽

pp. 761-774 ◽

Cited By ~ 1

Author(s):

Greta Minelgaite ◽

Nikki van Alst ◽

Diana Agnete Stephansen ◽

Ulla Elisabeth Bollmann ◽

Kai Bester ◽

...

Keyword(s):

Exploratory Study ◽

Benthic Diatom ◽

Land Uses ◽

Stormwater Ponds ◽

Diatom Communities

Download Full-text

HABITAT CHARACTERISTICS AND GRASSHOPPER COMMUNITY DYNAMICS ON MIXED-GRASS RANGELAND

The Canadian Entomologist ◽

10.4039/ent12389-1 ◽

1991 ◽

Vol 123 (1) ◽

pp. 89-105 ◽

Cited By ~ 17

Author(s):

Mark A. Quinn ◽

R.L. Kepner ◽

D.D. Walgenbach ◽

R.A. Bohls ◽

P.D. Pooler ◽

...

Keyword(s):

Community Structure ◽

Community Dynamics ◽

Detrended Correspondence Analysis ◽

Bouteloua Gracilis ◽

Community Change ◽

Habitat Characteristics ◽

Agropyron Smithii ◽

Spatial Gradients ◽

Mixed Grass ◽

The Difference

AbstractA study was conducted in Butte County of western South Dakota to determine the relationships between habitat characteristics and spatial and temporal changes in community structure of grasshoppers on mixed-grass rangeland. Detrended correspondence analysis (DCA) of 29 undisturbed grasshopper communities and correlation analysis of DCA axis values and habitat variables denned specific spatial gradients underlying the community structure of grasshoppers. Results indicated that grasshopper communities changed along a primary gradient of percentage of coverage of grasses, particularly Buchloe dactyloides (Nutt.) Engelm., and a secondary gradient of percentage composition of clay and sand in the soil.DCA of 24 grasshopper communities sampled in 1986 and 1987, multiple regression analysis, and factor analysis were used to determine the relationships between specific habitat characteristics and changes in communities of grasshoppers treated with either a nonselective insecticidal spray (malathion) or a selective insecticidal bait (bran bait with carbaryl). Results indicated that between-year change in community composition, or the difference between post-treatment communities in 1986 and 1987, was positively correlated with percentage of coverage of total grasses and forbs. Community malleability, defined as the tendency of a community to return to its predisturbed state, was greater in habitats with high coverages of Agropyron smithii Rydb. and Carex spp., low coverage of Bouteloua gracilis (H.B.K.) Lag. ex Steud., and low species richness of grasses. Our results emphasize the importance of habitat characteristics in structuring undisturbed grasshopper communities and in community change after perturbation with insecticides.

Download Full-text

Water quality assessment of benthic diatom communities for water quality in the subalpine karstic lakes of Jiuzhaigou, a world heritage site in China

Journal of Mountain Science ◽

10.1007/s11629-014-3392-7 ◽

2016 ◽

Vol 13 (9) ◽

pp. 1632-1644 ◽

Cited By ~ 3

Author(s):

Li-li Ouyang ◽

Yang-dong Pan ◽

Cheng-min Huang ◽

Ya Tang ◽

Jie Du ◽

...

Keyword(s):

Water Quality ◽

Quality Assessment ◽

Water Quality Assessment ◽

World Heritage ◽

Benthic Diatom ◽

World Heritage Site ◽

Heritage Site ◽

Karstic Lakes ◽

Diatom Communities

Download Full-text

Preservation of spatial and environmental gradients by death assemblages

Paleobiology ◽

10.1666/07081.1 ◽

2009 ◽

Vol 35 (1) ◽

pp. 119-145 ◽

Cited By ~ 37

Author(s):

Adam Tomašových ◽

Susan M. Kidwell

Keyword(s):

Community Structure ◽

Community Composition ◽

Environmental Gradients ◽

Compositional Variation ◽

Time Averaging ◽

Data Sets ◽

Square Root ◽

Spatial Gradients ◽

Death Assemblages ◽

The Impact

Although only a few studies have explicitly evaluated live-dead agreement of species and community responses to environmental and spatial gradients, paleoecological analyses implicitly assume that death assemblages capture these gradients accurately. We use nine data sets from modern, relatively undisturbed coastal study areas to evaluate how the response of living molluscan assemblages to environmental gradients (water depth and seafloor type; “environmental component” of a gradient) and geographic separation (“spatial component”) is captured by their death assemblages. We find that:1. Living assemblages vary in composition either in response to environmental gradients alone (consistent with a species-sorting model) or in response to a combination of environmental and spatial gradients (mass-effect model). None of the living assemblages support the neutral model (or the patch-dynamic model), in which variation in species abundance is related to the spatial configuration of stations alone. These findings also support assumptions that mollusk species consistently differ in responses to environmental gradients, and suggest that in the absence of postmortem bias, environmental gradients might be accurately captured by variation in species composition among death assemblages. Death assemblages do in fact respond uniquely to environmental gradients, and show a stronger response when abundances are square-root transformed to downplay the impact of numerically abundant species and increase the effect of rare species.2. Species' niche positions (position of maximum abundance) along bathymetric and sedimentary gradients in death assemblages show significantly positive rank correlations to species positions in living assemblages in seven of nine data sets (both square-root-transformed and presence-absence data).3. The proportion of compositional variation explained by environmental gradients in death assemblages is similar to that of counterpart living assemblages. Death assemblages thus show the same ability to capture environmental gradients as do living assemblages. In some instances compositional dissimilarities in death assemblages show higher rank correlation with spatial distances than with environmental gradients, but spatial structure in community composition is mainly driven by spatially structured environmental gradients.4. Death assemblages correctly identify the dominance of niche metacommunity models in mollusk communities, as revealed by counterpart living assemblages. This analysis of the environmental resolution of death assemblages thus supports fine-scale niche and paleoenvironmental analyses using molluscan fossil records. In spite of taphonomic processes and time-averaging effects that modify community composition, death assemblages largely capture the response of living communities to environmental gradients, partly because of redundancy in community structure that is inherently associated with multispecies assemblages. The molluscan data sets show some degree of redundancy as evidenced by the presence of at least two mutually exclusive subsets of species that replicate the community structure, and simple simulations show that between-sample relationships can be preserved and remain significant even when a large proportion of species is randomly removed from data sets.

Download Full-text