Biodiversity among mussels: separating the influence of sizes of mussels from the ages of patches

The role of habitat structure in controlling the composition of assemblages has often been studied, but is rarely manipulated so that it is distinguishable from other factors. Differences in habitat structure as determined by differences in mussel size structure may affect the diversity of assemblages associated with mussel beds. Previous studies examining the effect of the size of individual mussels in a patch on the diversity of associated macro-faunal assemblages confounded the age of the patch with the size of the mussels. We manipulated the age of mussel patches and the size of the mussels within them to test experimentally whether the size of mussels influenced the structure of associated assemblages. At one of the two locations considered, the structure of macro-faunal assemblages in patches of larger mussels differed significantly from those in patches of the same age composed of smaller mussels. At this location, the size of mussels did not affect species richness but the abundance and proportion of organisms present differed depending on the size of the mussels. Here patches of larger mussels contained greater numbers of Nematodes and Oligochaetes and a lower abundance of taxa such as Jaera forsmani and Lepidonotus clava. We also found that invertebrate assemblages in general differed between the two locations. The effect of the size structure of mussels, however, varied spatially demonstrating that the effect of habitat structure on the diversity of associated assemblages is context dependent.

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Effects of frond length on diverse gastropod assemblages in coralline turf

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315403006921h ◽

2003 ◽

Vol 83 (1) ◽

pp. 159-163 ◽

Cited By ~ 11

Author(s):

Brendan P. Kelaher

Keyword(s):

Habitat Structure ◽

Rocky Shore ◽

Negative Relationship ◽

Total Abundance ◽

Faunal Assemblages ◽

Vertical Scale ◽

Abundance And Diversity ◽

Frond Length ◽

Sydney Australia

Habitat mimics were used to investigate the role of coralline algal frond length in determining spatial patterns in diverse gastropod assemblages on a rocky shore near Sydney, Australia. Frond length represents the vertical scale component of habitat structure, which is rarely experimentally manipulated. Length of fronds did not explain differences between gastropod assemblages at different tidal heights or among patches of turf separated by tens of metres in mid-shore areas. In contrast, changes in frond length caused large differences in the structure of gastropod assemblages in low-shore areas. Contrary to previous studies, the total abundance and diversity of gastropods was greater in turf with short fronds than with long fronds. Possible mechanisms for this negative relationship are discussed. Overall, the vertical scale component of habitat structure can have strong effects on associated faunal assemblages, but the magnitude of these effects depend heavily on local environmental conditions (e.g. different tidal heights).

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Resistance, resilience, and patchiness of invertebrate assemblages in native tussock and pasture streams in New Zealand after a hydrological disturbance

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f03-061 ◽

2003 ◽

Vol 60 (6) ◽

pp. 731-739 ◽

Cited By ~ 30

Author(s):

Adriano S Melo ◽

Dev K Niyogi ◽

Christoph D Matthaei ◽

Colin R Townsend

Keyword(s):

Species Richness ◽

New Zealand ◽

Spatial Scales ◽

Patch Dynamics ◽

Natural Disturbance ◽

Species Density ◽

Land Uses ◽

Invertebrate Abundance ◽

Invertebrate Assemblages

We generated hydrological disturbances to investigate the role of disturbance in New Zealand streams in two land uses: native tussock grasslands and exotic pasture catchments. We tested whether physical differences in streambed structure confer higher resistance and resilience in tussock sites than in pasture sites. We also investigated changes in patchiness (at spatial scales larger than 0.06 m2) caused by the disturbance. Invertebrate abundance decreased immediately after the disturbance. Species density remained unchanged, but species richness (rarefied) increased. Eight days after the disturbance event, abundance and species richness (rarefied) were similar to those of samples collected immediately before the disturbance. Resistance (measured as decrease in abundance) and resilience (measured as recovery within 8 days) did not differ significantly between the land uses. Patchiness increased in both stream types immediately after the disturbance but decreased to predisturbance levels after 8 days. Disturbance caused a redistribution of individuals among patches, some receiving individuals, others losing individuals, and some remaining unchanged. Our results conform with predictions of the patch dynamics concept and are consistent with results of studies of natural disturbance caused by floods.

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Universality in biodiversity patterns: Variation in species-temperature and species-productivity relationships reveals a prominent role of productivity in diversity gradients

10.1101/2020.12.16.422752 ◽

2020 ◽

Author(s):

Eliška Bohdalková ◽

Anna Toszogyova ◽

Irena Šímová ◽

David Storch

Keyword(s):

Species Richness ◽

Spatial Scale ◽

Effect Of Temperature ◽

Statistical Nature ◽

Biodiversity Patterns ◽

Diversity Gradients ◽

Context Dependent ◽

Richness Patterns ◽

Species Productivity

Temperature and productivity appear as universal positive correlates of species richness. However, the strength and the shape of species-temperature (STR) and species-productivity (SPR) relationships vary widely, and the causes of this variation are poorly known. We analysed (1) published species richness data for multiple taxa sampled in various regions and (2) different clades within vertebrate classes globally, to test for the effects of spatial scale and characteristics of examined taxa and regions on the strength and direction of STRs and SPRs. There are striking differences in the variation of the relationships among types of data, between ectotherms and endotherms and also between STRs and SPRs. Some sources of this variation are of statistical nature (e.g. the relationships are stronger if the range of temperature or productivity variation is wider), but non-statistical sources are more important and illuminate the processes responsible for the origin of biodiversity patterns. The SPRs are generally stronger and less variable than STRs, and SPR variation is weakly related to the explored factors - the SPRs are stronger in warmer regions in ectotherms, while clade size is the only factor consistently affecting the strength of the SPR in endotherms. In contrast, STRs are weaker and more variable, and this variation is linked to region characteristics - most importantly, STRs are stronger in the regions where temperature positively correlates with productivity, indicating that productivity plays a role even in the STRs. The effect of temperature on species richness is thus complex and context-dependent, while productivity is a more universal driver of species richness patterns, largely independent of particular characteristics of given region or taxon. Productivity thus appears as the main proximate driver of species richness patterns, probably due to its effect on the limits of the number of viable populations which can coexist in a given environment.

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Forming Impressions of Personality

Social Psychology ◽

10.1027/1864-9335/a000179 ◽

2014 ◽

Vol 45 (3) ◽

pp. 153-163 ◽

Cited By ~ 13

Author(s):

Sanne Nauts ◽

Oliver Langner ◽

Inge Huijsmans ◽

Roos Vonk ◽

Daniël H. J. Wigboldus

Keyword(s):

Impression Formation ◽

Context Dependent

Asch’s seminal research on “Forming Impressions of Personality” (1946) has widely been cited as providing evidence for a primacy-of-warmth effect, suggesting that warmth-related judgments have a stronger influence on impressions of personality than competence-related judgments (e.g., Fiske, Cuddy, & Glick, 2007 ; Wojciszke, 2005 ). Because this effect does not fit with Asch’s Gestalt-view on impression formation and does not readily follow from the data presented in his original paper, the goal of the present study was to critically examine and replicate the studies of Asch’s paper that are most relevant to the primacy-of-warmth effect. We found no evidence for a primacy-of-warmth effect. Instead, the role of warmth was highly context-dependent, and competence was at least as important in shaping impressions as warmth.

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The role of kinship in knowledge about medicinal plants: evidence for context-dependent model-based biases in cultural transmission?

Acta Botanica Brasilica ◽

10.1590/0102-33062018abb0340 ◽

2019 ◽

Vol 33 (2) ◽

pp. 370-375 ◽

Cited By ~ 2

Author(s):

Camilla de Carvalho de Brito ◽

Washington Soares Ferreira-Júnior ◽

Ulysses Paulino Albuquerque ◽

Marcelo Alves Ramos ◽

Taline Cristina da Silva ◽

...

Keyword(s):

Medicinal Plants ◽

Cultural Transmission ◽

Model Based ◽

Dependent Model ◽

Context Dependent

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Arthropod community structure in pastures of an island archipelago (Azores): looking for local–regional species richness patterns at fine-scales

Bulletin of Entomological Research ◽

10.1079/ber2004289 ◽

2004 ◽

Vol 94 (2) ◽

pp. 111-121 ◽

Cited By ~ 22

Author(s):

P.A.V. Borges ◽

V.K. Brown

Keyword(s):

Species Richness ◽

Regional Scale ◽

Local Scale ◽

Local Species Richness ◽

Β Diversity ◽

Arthropod Species ◽

Α Diversity ◽

Local Species ◽

Richness Patterns

AbstractThe arthropod species richness of pastures in three Azorean islands was used to examine the relationship between local and regional species richness over two years. Two groups of arthropods, spiders and sucking insects, representing two functionally different but common groups of pasture invertebrates were investigated. The local–regional species richness relationship was assessed over relatively fine scales: quadrats (= local scale) and within pastures (= regional scale). Mean plot species richness was used as a measure of local species richness (= α diversity) and regional species richness was estimated at the pasture level (= γ diversity) with the ‘first-order-Jackknife’ estimator. Three related issues were addressed: (i) the role of estimated regional species richness and variables operating at the local scale (vegetation structure and diversity) in determining local species richness; (ii) quantification of the relative contributions of α and β diversity to regional diversity using additive partitioning; and (iii) the occurrence of consistent patterns in different years by analysing independently between-year data. Species assemblages of spiders were saturated at the local scale (similar local species richness and increasing β-diversity in richer regions) and were more dependent on vegetational structure than regional species richness. Sucking insect herbivores, by contrast, exhibited a linear relationship between local and regional species richness, consistent with the proportional sampling model. The patterns were consistent between years. These results imply that for spiders local processes are important, with assemblages in a particular patch being constrained by habitat structure. In contrast, for sucking insects, local processes may be insignificant in structuring communities.

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Patchwork of oil and gas facilities in Saudi waters of the Arabian Gulf has the potential to enhance local fisheries production

ICES Journal of Marine Science ◽

10.1093/icesjms/fsv072 ◽

2015 ◽

Vol 72 (8) ◽

pp. 2398-2408 ◽

Cited By ~ 15

Author(s):

Lotfi Rabaoui ◽

Yu-Jia Lin ◽

Mohammad A. Qurban ◽

Rommel H. Maneja ◽

Javier Franco ◽

...

Keyword(s):

Oil And Gas ◽

Arabian Gulf ◽

Habitat Characteristics ◽

Small Fish ◽

Faunal Assemblages ◽

Fishery Resources ◽

Management Measures ◽

Coastal Embayments ◽

Oceanographic Variables

Abstract Because of the increasing oil industry development in the Arabian Gulf, hundreds of oil and gas facilities have been installed in both offshore and inshore areas during the last few decades. However, no studies have been conducted till now on the influence of these platforms on the structure and composition of marine faunal assemblages. The present work addresses this issue to propose environmental management measures connected to the utilization of fishery resources. Offshore and inshore surveys were carried out along the Saudi Gulf waters using trawl and beach-seine nets, respectively. Data relative to only fish (offshore) and fish and invertebrates (inshore) were collected concurrently with several factors: density of oil and gas facilities (offshore), distance to the nearest coastal platform (inshore), oceanographic variables, and habitat characteristics. Results of offshore surveys indicated higher fish density—both total and of fishery resources—in locations with a higher number of oil and gas facilities within a 5 km radius, whereas biomass density was not significantly different. Hence, oil and gas facilities seem to serve as nursery areas for small fish. For inshore communities, more species and diversity were found in stations closer to coastal oil and gas facilities. In addition, among the five coastal embayments sampled, those with more oil and gas facilities had more species. The findings of the present work support the hypothesis of a positive net ecological role of oil and gas platforms of the Saudi Arabian Gulf, with the implication that this effect could be extended to improve the sustainability of important fishery resources.

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