Erratum: Grounded Ground Birds and Surfing Canopy Birds: Variation of Foraging Stratum Breadth Observed in Neotropical Forest Birds and Tested with Simulation Models Using Boundary Constraints

The Auk ◽  
2003 ◽  
Vol 120 (1) ◽  
pp. 235-235
Author(s):  
Bruno A. Walther
Keyword(s):  
Simulation Models ◽  
Forest Birds ◽  
Boundary Constraints ◽  
Neotropical Forest

scholarly journals Grounded Ground Birds and Surfing Canopy Birds: Variation of Foraging Stratum Breadth Observed in Neotropical Forest Birds and Tested With Simulation Models Using Boundary Constraints

The Auk ◽  
2002 ◽  
Vol 119 (3) ◽  
pp. 658-675 ◽  
Author(s):  
Bruno A. Walther
Keyword(s):  
Comparative Method ◽  
Bird Species ◽  
Simulation Models ◽  
Forest Birds ◽  
Published Data ◽  
Vegetation Density ◽  
Boundary Constraints ◽  
Advantages And Disadvantages ◽  
Parabolic Relationship ◽  
The Relationship

Abstract Vertical stratification of bird species has been intensively studied in temperate as well as tropical forest bird communities. One question that has received less attention is the variation of foraging stratum breadth. Hypotheses trying to explain that variation are based on differences in perception, evasion, adaptation, competition, and environmental and geometric boundary constraints. Although some predict that foraging strata near the ground should be narrower than those near the canopy, others predict that strata in the midstory should be broadest. These hypotheses were tested using observational data of 92 rainforest bird species. Observations were made from or near a 40 m high canopy crane situated close to the Surumoni River (3°10′N, 65°40′W) near Esmeralda, Estado Amazonas, southern Venezuela (Surumoni-Crane-Project). I found a highly significant parabolic relationship between mean foraging height and its standard deviation showing that midstory bird species foraged in a broader stratum than either understory or canopy species. Using a conservative comparative method, I also showed that the relationship was not the result of the phylogenetic relatedness of the species involved. Analysis of previously published data supports the relationship for two other tropical avifaunas. Because the ground and the outer canopy represent geometric boundaries to the movement of most forest birds, two simulation models were used to test whether midstory species may simply have a broader stratum because they are less constrained in their movements than species near the boundaries. The “random model” allowed individuals to move randomly between the two boundaries. It illustrated that boundary constraints alone cannot explain the observed parabolic relationship. In the “preference model,” individuals tended to move back to their preferred height within the forest column. That model simulated the observed parabolic relationship once a sufficient number of time steps had been reached, suggesting that a simple combination of geometric boundaries and preference for a specific foraging height may generate narrower strata near the boundaries. The other hypotheses only explain the parabolic relationship if other factors (e.g. vegetation density) are vertically distributed in such a way as to generate the observed parabolic pattern. Finally, I briefly discuss the advantages and disadvantages of using raw data in across-species analyses versus corrected data in phylogenetically-controlled analyses.

Numerical Simulation of Distributed Dynamic Systems using Hybrid Tools of Intelligent Computing

2013 ◽  
pp. 360-383
Author(s):  
Fethi H. Bellamine ◽  
Aymen Gdouda
Keyword(s):  
Numerical Simulation ◽  
Differential Equations ◽  
Dynamic Systems ◽  
Mixed Boundary ◽  
Simulation Models ◽  
Control Synthesis ◽  
Scaling Analysis ◽  
Intelligent Computing ◽  
Boundary Constraints ◽  
Reduction Techniques

Developing fast and accurate numerical simulation models for predicting, controlling, designing, and optimizing the behavior of distributed dynamic systems is of interest to many researchers in various fields of science and engineering. These systems are described by a set of differential equations with homogenous or mixed boundary constraints. Examples of such systems are found, for example, in many networked industrial systems. The purpose of the present work is to review techniques of hybrid soft computing along with generalized scaling analysis for the solution of a set of differential equations characterizing distributed dynamic systems. The authors also review reduction techniques. This paves the way to control synthesis of real-time robust realizable controllers.

scholarly journals A phylogenetic approach to disentangling the role of competition and habitat filtering in community assembly of Neotropical forest birds

2010 ◽  
Vol 79 (6) ◽  
pp. 1181-1192 ◽  
Author(s):  
Juan Pablo Gómez ◽  
Gustavo A. Bravo ◽  
Robb T. Brumfield ◽  
José G. Tello ◽  
Carlos Daniel Cadena
Keyword(s):  
Community Assembly ◽  
Forest Birds ◽  
Habitat Filtering ◽  
Neotropical Forest

Myoglobin as a conservation‐relevant predictor of short‐distance flight capacity in Neotropical forest birds

Biotropica ◽  
2022 ◽  
Author(s):  
Kelsey Condell ◽  
W. Douglas Robinson ◽  
Randall P. Moore ◽  
Bryan Rourke
Keyword(s):  
Short Distance ◽  
Forest Birds ◽  
Neotropical Forest ◽  
Flight Capacity

scholarly journals Conservation of large avian frugivores and the management of Neotropical protected areas

Oryx ◽  
1991 ◽  
Vol 25 (1) ◽  
pp. 50-55 ◽  
Author(s):  
Stuart D. Strahl ◽  
Alejandro Grajal
Keyword(s):  
Protected Areas ◽  
Conservation Status ◽  
Field Research ◽  
Field Work ◽  
Forest Birds ◽  
Neotropical Forests ◽  
Neotropical Forest ◽  
History Of ◽  
Ecosystem Level ◽  
Conservation Organizations

Large frugivorous forest birds are among the most endangered avian groups in the Neotropics. Despite this fact, there has been little field work on members of these groups or on other large Neotropical forest birds. While current studies of Neotropical forests are beginning to provide data for reserve management at the ecosystem level, we lack information for management of particular species or habitats. Throughout Latin America, large forest frugivores are economically important as food, as pets or in local crafts. They can also be important seed dispersers and can be used as indicator species of habitat disturbance in protected areas. The conservation status of these birds demands more attention and commitment from conservation organizations and the scientific community in general. Further field research should focus on the basic ecology and natural history of endangered and non-endangered species. These studies will aid in developing badly needed long-term management and monitoring plans both for populations of large forest frugivores and their habitats.

Correlation of Pore Structure and Permeability by SEM-Image Analysis

1990 ◽  
Vol 48 (1) ◽  
pp. 428-429
Author(s):  
C. A. Callender ◽  
Wm. C. Dawson ◽  
J. J. Funk
Keyword(s):  
Image Analysis ◽  
Pore Structure ◽  
Imaging System ◽  
Pore Space ◽  
Simulation Models ◽  
Image Analyzer ◽  
Imaging Data ◽  
Sem Images ◽  
Thin Sections ◽  
Rock Types

The geometric structure of pore space in some carbonate rocks can be correlated with petrophysical measurements by quantitatively analyzing binaries generated from SEM images. Reservoirs with similar porosities can have markedly different permeabilities. Image analysis identifies which characteristics of a rock are responsible for the permeability differences. Imaging data can explain unusual fluid flow patterns which, in turn, can improve production simulation models.Analytical SchemeOur sample suite consists of 30 Middle East carbonates having porosities ranging from 21 to 28% and permeabilities from 92 to 2153 md. Engineering tests reveal the lack of a consistent (predictable) relationship between porosity and permeability (Fig. 1). Finely polished thin sections were studied petrographically to determine rock texture. The studied thin sections represent four petrographically distinct carbonate rock types ranging from compacted, poorly-sorted, dolomitized, intraclastic grainstones to well-sorted, foraminiferal,ooid, peloidal grainstones. The samples were analyzed for pore structure by a Tracor Northern 5500 IPP 5B/80 image analyzer and a 80386 microprocessor-based imaging system. Between 30 and 50 SEM-generated backscattered electron images (frames) were collected per thin section. Binaries were created from the gray level that represents the pore space. Calculated values were averaged and the data analyzed to determine which geological pore structure characteristics actually affect permeability.

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