EMPIRICAL SUPPORT FOR THE POSSIBLE APPLICATION OF MODIFIED ELLENBERG INDICES TO THE STUDY OF ENVIRONMENTAL GRADIENTS ON DYNAMIC IRISH WETLANDS— EVIDENCE FROM SKEALOGHAN TURLOUGH, COUNTY MAYO

Christopher D. Williams; Boudewijn Beltman; James Moran; Micheline Sheehy Skeffington; Michael J. Gormally

doi:10.3318/bioe.2011.02

EMPIRICAL SUPPORT FOR THE POSSIBLE APPLICATION OF MODIFIED ELLENBERG INDICES TO THE STUDY OF ENVIRONMENTAL GRADIENTS ON DYNAMIC IRISH WETLANDS—EVIDENCE FROM SKEALOGHAN TURLOUGH, COUNTY MAYO

Biology & Environment Proceedings of the Royal Irish Academy ◽

10.1353/bae.2011.0021 ◽

2011 ◽

Vol 111B (1) ◽

pp. 19-31

Author(s):

Christopher D. Williams ◽

Boudewijn Beltman ◽

James Moran ◽

Micheline Sheehy Skeffington ◽

Michael J. Gormally

Keyword(s):

Environmental Gradients ◽

Empirical Support ◽

County Mayo

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Testing biodiversity theory using species richness of reef-building corals across a depth gradient

Biology Letters ◽

10.1098/rsbl.2019.0493 ◽

2019 ◽

Vol 15 (10) ◽

pp. 20190493 ◽

Cited By ~ 2

Author(s):

T. Edward Roberts ◽

Sally A. Keith ◽

Carsten Rahbek ◽

Tom C. L. Bridge ◽

M. Julian Caley ◽

...

Keyword(s):

Species Richness ◽

Large Scale ◽

Coral Species ◽

Environmental Gradients ◽

Abiotic Factors ◽

Empirical Support ◽

Null Model ◽

Local Scale ◽

Small Scale ◽

Energy Availability

Natural environmental gradients encompass systematic variation in abiotic factors that can be exploited to test competing explanations of biodiversity patterns. The species–energy (SE) hypothesis attempts to explain species richness gradients as a function of energy availability. However, limited empirical support for SE is often attributed to idiosyncratic, local-scale processes distorting the underlying SE relationship. Meanwhile, studies are also often confounded by factors such as sampling biases, dispersal boundaries and unclear definitions of energy availability. Here, we used spatially structured observations of 8460 colonies of photo-symbiotic reef-building corals and a null-model to test whether energy can explain observed coral species richness over depth. Species richness was left-skewed, hump-shaped and unrelated to energy availability. While local-scale processes were evident, their influence on species richness was insufficient to reconcile observations with model predictions. Therefore, energy availability, either in isolation or in combination with local deterministic processes, was unable to explain coral species richness across depth. Our results demonstrate that local-scale processes do not necessarily explain deviations in species richness from theoretical models, and that the use of idiosyncratic small-scale factors to explain large-scale ecological patterns requires the utmost caution.

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Depth-Dependent Diversity Patterns of Rocky Subtidal Macrobenthic Communities Along a Temperate Fjord in Northern Chilean Patagonia

Frontiers in Marine Science ◽

10.3389/fmars.2021.635855 ◽

2021 ◽

Vol 8 ◽

Author(s):

Vicente I. Villalobos ◽

Nelson Valdivia ◽

Günter Försterra ◽

Stacy Ballyram ◽

Juan Pablo Espinoza ◽

...

Keyword(s):

Spatial Variation ◽

Water Column ◽

Environmental Changes ◽

Environmental Gradients ◽

Empirical Support ◽

Depth Gradient ◽

Macrobenthic Communities ◽

Rocky Subtidal ◽

Chilean Patagonia ◽

Depth Ranges

Understanding the distribution of biodiversity along environmental gradients allows us to predict how communities respond to natural and anthropogenic impacts. In fjord ecosystems, the overlap of strong salinity and temperature gradients provides us with the opportunity to assess the spatial variation of biodiversity along abiotic environmental gradients. However, in Northern Chilean Patagonia (NCP), a unique and at the same time threatened fjord system, the variation of macrobenthic communities along abiotic environmental gradients is still poorly known. Here, we tested whether macrobenthic species diversity and community structure followed systematic patterns of variation according to the spatial variation in salinity and temperature in Comau Fjord, NCP. A spatially extensive nested sampling design was used to quantify the abundance of subtidal macrobenthic species along the fjord axis (fjord sections: head, middle, and mouth) and a depth gradient (0–21 m). The vertical structure of the water column was strongly stratified at the head of the fjord, characterized by a superficial (depth to ca. 5 m) low-salinity and relatively colder layer that shallowed and decayed toward the mouth of the fjord. The biotic variation followed, in part, this abiotic spatial pattern. Species richness peaked at high salinities (>27 psu) between 5 and 10 m in the head section and between 15 and 21 m in the middle and mouth sections. Diversity and evenness were also highest at these salinities and depth ranges in the head and middle sections, but at shallower depth ranges in the mouth. Information theory-based model selection provided a strong empirical support to the depth- and section-dependent salinity, but not temperature, effects on the three biodiversity metrics. Erect algae and the edible mussel Aulacomya atra numerically dominated in shallow water (0–3 m) at the head and the middle of the fjord, coinciding with the horizontal extension of the low-density water layer—these taxa were further replaced by the crustose algae Lithothamnion sp. and deep-dwelling suspension filters (e.g., corals, polychaetes, and sponges) along depth gradient. Macrobenthic biodiversity correlated, therefore, with the influence of freshwater inputs and the density-driven stratification of the water column in this ecosystem. The spatially variable (across both, horizontal and vertical fjord axes) thresholds observed in our study question the widely accepted pattern of increasing biodiversity with increasing distance from the head of estuarine ecosystems. Finally, non-linear environmental stress models provide us a strong predictive power to understand the responses of these unique ecosystems to natural and anthropogenic environmental changes.

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South Asian Stories: Firsthand Client Perspectives on Barriers to Accessing Speech-Language Pathology Services

Perspectives on Communication Disorders and Sciences in Culturally and Linguistically Diverse Populations ◽

10.1044/cds19.1.29 ◽

2012 ◽

Vol 19 (1) ◽

pp. 29-36 ◽

Cited By ~ 6

Author(s):

Nidhi Mahendra

Keyword(s):

South Asian ◽

Empirical Support ◽

Communication Disorders ◽

Speech Language Pathology ◽

Client Experiences ◽

Individual Interviews ◽

Timely Access ◽

Phenomenological Perspective ◽

Case Vignettes ◽

Language Pathology

This article details the experience of two South Asian individuals with family members who had communication disorders. I provide information on intrinsic and extrinsic barriers reported by these clients in responses to a survey and during individual ethnographic interviews. These data are part of a larger study and provide empirical support of cultural and linguistic barriers that may impede timely access to and utilization of speech-language pathology (SLP) services. The purpose of this article is to shed light on barriers and facilitators that influence South Asian clients' access to SLP services. I provide and briefly analyze two case vignettes to provide readers a phenomenological perspective on client experiences. Data about barriers limiting access to SLP services were obtained via client surveys and individual interviews. These two clients' data were extracted from a larger study (Mahendra, Scullion, Hamerschlag, Cooper, & La, 2011) in which 52 racially/ethnically diverse clients participated. Survey items and interview questions were designed to elicit information about client experiences when accessing SLP services. Results reveal specific intrinsic and extrinsic barriers that affected two South Asian clients' access to SLP services and have important implications for all providers.

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Capturing the Four-Phase Team Adaptation Process With Behaviorally Anchored Rating Scales (BARS)

European Journal of Psychological Assessment ◽

10.1027/1015-5759/a000503 ◽

2020 ◽

Vol 36 (2) ◽

pp. 336-347

Author(s):

Eleni Georganta ◽

Felix C. Brodbeck

Keyword(s):

Rating Scales ◽

Empirical Support ◽

Team Development ◽

Adaptation Process ◽

Adaptation Studies ◽

Team Processes ◽

Team Adaptation ◽

The Common ◽

Acceptable Reliability ◽

Adaptation Phase

Abstract. As a response to the lack of quantitative and reliable measures of the team adaptation process, the aim of the present study was to develop and validate an instrument for assessing the four phases of the team adaptation process as described by Rosen and colleagues (2011) . Two trained raters and two subject matter expert groups contributed to the development of four behaviorally anchored rating scales (BARS) that span across the spectrum of team processes involved in each team adaptation phase. To validate the four BARS, two different trained raters assessed independently the team adaptation phases of 66 four-person teams. The validation study provided empirical support for the BARS’ psychometric adequacy. The BARS measures overcame the common middle anchor problem, showed sensitivity in differentiating between teams and between the four phases, showed evidence for acceptable reliability, construct, and criterion validity, and supported the theoretical team adaptation process assumptions. The study contributes to research and praxis by enabling the direct assessment of the overall team adaptation process, thereby facilitating our understanding of this complex phenomenon. This allows the identification of behavioral strengths and weaknesses for targeted team development and comprehensive team adaptation studies.

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