scholarly journals Decoupling the response of an estuarine shrimp to architectural components of habitat structure

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2244 ◽  
Author(s):  
Jeffrey A. Crooks ◽  
Andrew L. Chang ◽  
Gregory M. Ruiz
Keyword(s):  
Fractal Dimension ◽  
Interspecific Competition ◽  
Habitat Structure ◽  
Habitat Type ◽  
Physical Structure ◽  
Structural Elements ◽  
Palaemon Macrodactylus ◽  
Proximate Factors

In order to explore biotic attraction to structure, we examined how the amount and arrangement of artificial biotic stalks affected responses of a shrimp,Palaemon macrodactylus, absent other proximate factors such as predation or interspecific competition. In aquaria, we tested the effect of differing densities of both un-branched and branched stalks, where the amount of material in the branched stalk equaled four-times that of the un-branched. The results clearly showed that it was the amount of material, not how it was arranged, that elicited responses from shrimp. Also, although stalks were not purposefully designed to mimic structural elements found in nature, they did resemble biogenic structure such as hydroids, algae, or plants. In order to test shrimp attraction to a different, perhaps more unfamiliar habitat type, we examined responses to plastic “army men.” These structural elements elicited similar attraction of shrimp, and, in general, shrimp response correlated well with the fractal dimension of both stalks and army men. Overall, these results indicate that attraction to physical structure, regardless of its nature, may be an important driver of high abundances often associated with complex habitats.

The interrelation between physical and mechanical properties of the polymeric composite and fractal dimension of structural elements its surface

2021 ◽  
pp. 54-60
Author(s):  
Val.I. Surikov ◽  
◽  
E.A. Rogachev ◽  
A.M. Lasitsa ◽  
◽  
...  
Keyword(s):  
Fractal Dimension ◽  
Physical And Mechanical Properties ◽  
Polymeric Composite ◽  
Polymeric Composite Material ◽  
Structural Elements ◽  
Qualitative And Quantitative Analysis ◽  
Force Microscopy ◽  
Qualitative And Quantitative ◽  
Atomic Force ◽  
Dimension Parameter

The paper shows the promising use of the "fractal dimension" parameter for qualitative and quantitative analysis of the surface structure of samples based of micrographs obtained by scanning electron microscopy and atomic force microscopy. The interrelation of this parameter with some mechanical characteristics of polymeric composite material PTFE-3%tu121 is investigated.

Synaptic clef segmentation method based on fractal dimension for ATUM-SEM image of mouse cortex

2021 ◽  
pp. 2150038
Author(s):  
Chao Ma ◽  
Lijun Shen ◽  
Hao Deng ◽  
Jialin Li
Keyword(s):  
Fractal Dimension ◽  
Physical Structure ◽  
Noise Performance ◽  
Segmentation Method ◽  
Technical Advance ◽  
Image Stack ◽  
Sem Image ◽  
The Neural Network ◽  
Mouse Cortex ◽  
The Stability

It is well known that neurons communicate through synapses in the nervous system, and the size, morphology, and connectivity of synapses determine the functional properties of the neural network. Therefore, synapses have always been one of the key objects of neuroscience. Due to the technical advance in electron microscope (EM), the physical structure of synapses can be observed at high resolution. Nevbarheless, to date, the automatic analysis of the synapse in EM images is still a challenging task. In this paper, we proposed a fractal dimension-based segmentation method for synaptic clef of mouse cortex on EM image stack. Our method does not require a lot of groundtruth to train the model, and shows better adaptive anti-noise performance. That should be ascribed to the stability of segmentation-related key parameters in the data from same tissue. In this way, we only need to give initial values, and then gradually adjust these key parameters. Experiments reveal that our method achieves the desired results, and reduces the time in artificial annotating, so that researchers can focus more on the analysis of segmentation results.

scholarly journals Associations between Benthic Cover and Habitat Complexity Metrics Obtained from 3D Reconstruction of Coral Reefs at Different Resolutions

2020 ◽  
Vol 12 (6) ◽  
pp. 1011 ◽  
Author(s):  
Atsuko Fukunaga ◽  
John H. R. Burns ◽  
Kailey H. Pascoe ◽  
Randall K. Kosaki
Keyword(s):  
Fractal Dimension ◽  
Coral Reefs ◽  
Habitat Structure ◽  
Coral Cover ◽  
Three Dimensional ◽  
Structural Complexity ◽  
Coralline Algae ◽  
Crustose Coralline Algae ◽  
Surface Areas ◽  
Abundance And Diversity

Quantifying the three-dimensional (3D) habitat structure of coral reefs is an important aspect of coral reef monitoring, as habitat architecture affects the abundance and diversity of reef organisms. Here, we used photogrammetric techniques to generate 3D reconstructions of coral reefs and examined relationships between benthic cover and various habitat metrics obtained at six different resolutions of raster cells, ranging from 1 to 32 cm. For metrics of 3D structural complexity, fractal dimension, which utilizes information on 3D surface areas obtained at different resolutions, and vector ruggedness measure (VRM) obtained at 1-, 2- or 4-cm resolution correlated well with benthic cover, with a relatively large amount of variability in these metrics being explained by the proportions of corals and crustose coralline algae. Curvature measures were, on the other hand, correlated with branching and mounding coral cover when obtained at 1-cm resolution, but the amount of variability explained by benthic cover was generally very low when obtained at all other resolutions. These results show that either fractal dimension or VRM obtained at 1-, 2- or 4-cm resolution, along with curvature obtained at 1-cm resolution, can effectively capture the 3D habitat structure provided by specific benthic organisms.

scholarly journals Analysis for Underwater Sound on Natural River Habitat

2018 ◽  
Vol 40 ◽  
pp. 02047
Author(s):  
Jung-Eun Gu ◽  
Sang Hwa Jung ◽  
Joongu Kang ◽  
Hyoseop Woo
Keyword(s):  
Underwater Acoustics ◽  
Fish Habitat ◽  
Habitat Type ◽  
High Water ◽  
Physical Structure ◽  
Physical Habitat ◽  
Hydraulic Characteristics ◽  
Underwater Sound ◽  
Underwater Acoustic ◽  
Sound Environment

A riffle-pool structure is a representative physical structure of bed in rivers. The change in the physical parameter of the habitat could lead to changes in the sound environment of rivers, which are expressed by underwater acoustics. This change in underwater sound affects fish habitat. In this study, the changes of underwater acoustics were analyzed according to the change of pool-riffle sequence in a natural river. And the correlation between underwater acoustics and hydraulic characteristics was investigated. The survey for underwater acoustics was performed in the Namdae stream where is in Gangwon province. This stream belongs to the Han River basin and the river length is 39.01 km and the catchment area is 127.56 km2. The Namdae stream is a river that accounts for more than 70% of salmon returning to South Korea. The spawning salmon will return to this area around November after growing in the Bering Sea. It is important to manage the fish habitat in this river so there is a lot of research on the enhancement of fish habitat. Hydraulic characteristics were changed by the river bed structure. In this study, we investigated the relationship between underwater acoustic characteristics and hydraulic factors such as riverbed material, flow rate and water depth of each habitat type at 12 sites. The characteristics of underwater acoustic differed relative to different hydraulic factors of the two habitats, which is riffle and pool. The sound pressure level of riffles was relatively higher than that of the pools due to bed materials, shallow depth and high water velocity of riffles. In the future, it is considered that the underwater sound can be utilized as a parameter to evaluate the physical habitat environment of the river.

Interspecific Competition and Population Control in Freshwater Fish

1956 ◽  
Vol 13 (3) ◽  
pp. 327-342 ◽  
Author(s):  
P. A. Larkin
Keyword(s):  
Interspecific Competition ◽  
Freshwater Fish ◽  
Quantitative Data ◽  
Population Control ◽  
Feeding Habits ◽  
Reproductive Potential ◽  
Habitat Type ◽  
Fish Populations ◽  
Population Interaction

Interspecific competition is defined as the demand of more than one organism for the same resource of the environment in excess of immediate supply. When two species are "competing for a niche" the term competition has been used to include phenomena such as predation of the two species on each other, competition to avoid a parasite, etc. Making this distinction in natural situations is unrealistic. In the limited sense in which interspecific competition is defined above, it is a discrete phenomenon, which with other phenomena such as predation, can be measured as a factor involved in interaction between species.Freshwater environments offer comparatively few opportunities for specialization in fishes. In consequence many species have a relatively wide tolerance of habitat type, a flexibility of feeding habits and in general share many resources of their environment with several other species of fish. Cannibalism and mutual predation are common complications of competitive relationships between species. The organization of freshwater fish communities is thus characterized by breadth at each level of the food chain rather than by a height of a pyramid of numbers. Flexible growth rate and high reproductive potential permit fish populations to tide over unfavorable periods of competition. In these circumstances it is difficult to separate the role of interspecific competition from other phenomena as a factor of population control. As a subordinate factor, predisposing fish to loss from other causes, interspecific competition may act to influence population levels. There is need for quantitative data and mathematical models for study of the types of population interaction typical in freshwater fish associations.

scholarly journals Orchid bee fauna responds to habitat complexity on a savanna area (Cerrado) in Brazil.

Sociobiology ◽  
2016 ◽  
Vol 63 (2) ◽  
pp. 819 ◽  
Author(s):  
Yasmine Antonini ◽  
Rodrigo Assunção Silveira ◽  
Márcio Oliveira ◽  
Cristiane Martins ◽  
Reisla Oliveira
Keyword(s):  
Species Richness ◽  
Species Diversity ◽  
Habitat Complexity ◽  
Habitat Structure ◽  
Dominant Species ◽  
Large Range ◽  
Physical Structure ◽  
High Complexity ◽  
Orchid Bee ◽  
Species Richness And Abundance

Habitat structure and complexity may broadly affect the diversity and composition of a variety of fauna in terrestrial systems. Here we investigated responses of orchid bee assemblages to habitat complexity, with the aim of assessing complexity as a useful surrogate for species diversity of this group. We test the following hypotheses: (i) There is a greater species richness and abundance of orchid bee in sites with high habitat complexity than lower habitat complexity; (ii) High habitat complexity sites have a different species composition of orchid bee than lower habitat complexity sites. For the purposes of our study, we defined habitat complexity as the heterogeneity in the arrangement in physical structure of habitat (vegetation), although there are a large range of operational definitions in the literature. As result, orchid bee species richness was higher in high complexity areas while community composition was not affected by habitat complexity, because Euglossa melanotricha and E. leucotricha were the dominant species, occurring in both environments. Habitat complexity, measured as a function of differences in multiple strata in forests, may be of great worth as a surrogate for the diversity of a range of arthropod groups including orchid bees. 

Experimental removal reveals only weak interspecific competition between two coexisting lizards

2018 ◽  
Vol 96 (8) ◽  
pp. 888-896 ◽  
Author(s):  
James E. Paterson ◽  
Stacey L. Weiss ◽  
Gabriel Blouin-Demers
Keyword(s):  
Habitat Selection ◽  
Interspecific Competition ◽  
Habitat Type ◽  
Microhabitat Use ◽  
Ecological Communities ◽  
Urosaurus Ornatus ◽  
Tree Lizards ◽  
Coexisting Species ◽  
Resource Levels ◽  
Sceloporus Virgatus

Competition for resources is an important mechanism that shapes ecological communities. Interspecific competition can affect habitat selection, fitness, and abundance in animals. We used a removal experiment and mark–recapture to test the hypothesis that competition with the larger and more abundant Striped Plateau Lizard (Sceloporus virgatus H.M. Smith, 1938) limits habitat selection, fitness, and abundance in Ornate Tree Lizards (Urosaurus ornatus (Baird in Baird and Girard, 1852)). Ornate Tree Lizards in the plots where Striped Plateau Lizards were removed switched between habitat types more frequently and moved farther than Ornate Tree Lizards in control plots. However, there were no significant changes in the relative densities of Ornate Tree Lizards in each habitat type or in microhabitat use. We also found no changes in growth rates, survival, or abundance of Ornate Tree Lizards in response to the removal of Striped Plateau Lizards. Our results suggest that interspecific competition was not strong enough to limit habitat use or abundance of Ornate Tree Lizards. Perhaps interspecific competition is weak between coexisting species when resource levels are not severely depleted. Therefore, it is important to consider environmental conditions when assessing the importance of interspecific competition.

scholarly journals An exclusion experiment to study the influence of habitat structure provided by Mussismilia corals (Cnidaria; Anthozoa) on the predation of associated crustaceans

2019 ◽  
Vol 73 (1) ◽  
Author(s):  
Marcos M. Nogueira ◽  
Elizabeth Neves ◽  
Rodrigo Johnsson
Keyword(s):  
Habitat Structure ◽  
Coral Species ◽  
Physical Structure ◽  
Foraging Efficiency ◽  
Associated Fauna ◽  
Exclusion Experiment ◽  
Community Organisation ◽  
Predation Intensity ◽  
Crustacean Assemblage

Abstract Predation is an interaction between species that influences community organisation by the direct consumption of prey, influencing prey numbers, behaviours and traits. The intensity of predation is greatly influenced by the environment, and the physical structure of habitats may influence predation intensity by providing refuge for prey or reducing the foraging efficiency of predators. In this context, the aim of the present study is to verify the influence of predation on the richness and density patterns of crustaceans inhabiting different species of Mussismilia corals, which provide various habitat structures for the associated fauna. We conducted an exclusion experiment to include total, partial and no cage treatments. The richness and density of crustaceans differed among coral species and cage treatments, except between partial cage and no cage treatment. Mussismilia harttii showed higher richness and density in uncaged and partial cage treatments compared with M. braziliensis, which in turn showed higher values than M. hispida. These findings indicate the importance of predation in the structure of crustacean assemblage associated with Mussismilia species and that differences in the richness and abundance of associated fauna result from the different habitat structures provided by each species of Mussismilia.

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