scholarly journals Spatial patterns of snake diversity in an urban area of north-east Brazil

2019 ◽  
pp. 274-281
Author(s):  
Rafaela Franca
Keyword(s):  
Urban Area ◽  
Ordinary Kriging ◽  
Distribution Patterns ◽  
Nearest Neighbour ◽  
University Campus ◽  
Neighbour Distance ◽  
Distance Analysis ◽  
North East ◽  
Animal Populations ◽  
Conservation Actions

The distribution of animal populations within an assemblage includes a wide variety of patterns, which are fundamental to understanding population dynamics and aid in conservation actions. We examined a snake assemblage in an urban area to describe species distribution patterns and to identify which places are more likely to contain snakes, both venomous and non-venomous. The study was conducted in the urban area of the municipality of Rio Tinto in north-east Brazil. We used a geostatistical modelling technique called ordinary kriging to identify which places were more likely to contain snakes, and a statistical spatial method (average nearest neighbour distance) to detect distribution patterns of snake species within the study area. A total of 291 individuals distributed among 28 species were recorded. The snakes were found in streets, homes, churches, university campus, streams, and even in local supermarkets. Ordinary kriging showed that the area of distribution of individuals was concentrated at three distinct points located in the centre of the urban area. The significant results of the average nearest neighbour distance analysis showed a clustered distribution for two species and dispersed distributions for eight species. Information on urban sites where snakes are more likely to be found is important not only for conservation, but also to help local citizens better understand and live amongst snakes

ELASTIC PROPERTIES OF STRAINED FCC AND HCP IRON

1993 ◽  
Vol 07 (01n03) ◽  
pp. 207-211
Author(s):  
T. KRAFT ◽  
M. METHFESSEL ◽  
M. VAN SCHILFGAARDE ◽  
M. SCHEFFLER
Keyword(s):  
Energy Cost ◽  
Interplanar Distance ◽  
Orbital Method ◽  
Full Potential ◽  
Local Spin Density Approximation ◽  
Nearest Neighbour ◽  
Density Approximation ◽  
Neighbour Distance ◽  
Large Lattice ◽  
Fcc Phase

Using the full-potential linear muffin-tin orbital method within the local spin-density approximation we analyse the influence of the nearest neighbour distance on fcc(111) or hcp(0001) iron layers. The LDA-LSDA error in describing ferromagnetic phases is determined to be at least 15 mRy/atom. As a consequence of this error, our calculations favour paramagnetic ground states. In this sense, the reported results have some model character. However, our analysis of the elastic energy cost under distortions should hold for transition metals in general. Allowing relaxations of the interplanar distance the fcc phase can become energetically favourable over the hcp phase at large lattice mismatches. The main reason for this behaviour is the enhanced stiffness of the hcp interplanar bonds due to the shortening of the axial c/a ratio.

scholarly journals Modeling the spatial structure of the endemic mara (Dolichotis patagonum) across modified landscapes

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6367 ◽  
Author(s):  
Milagros Antún ◽  
Ricardo Baldi
Keyword(s):  
Spatial Structure ◽  
Spatial Variation ◽  
Spatial Models ◽  
Distribution Patterns ◽  
Negative Consequences ◽  
Human Presence ◽  
Species Response ◽  
Conservation Actions ◽  
Density Surface ◽  
Abundance And Distribution

Across modified landscapes, anthropic factors can affect habitat selection by animals and consequently their abundance and distribution patterns. The study of the spatial structure of wild populations is crucial to gain knowledge on species’ response to habitat quality, and a key for the design and implementation of conservation actions. This is particularly important for a low-density and widely distributed species such as the mara (Dolichotis patagonum), a large rodent endemic to Argentina across the Monte and Patagonian drylands where extensive sheep ranching predominates. We aimed to assess the spatial variation in the abundance of maras and to identify the natural and anthropic factors influencing the observed patterns in Península Valdés, a representative landscape of Patagonia. We conducted ground surveys during the austral autumn from 2015 to 2017. We built density surface models to account for the variation in mara abundance, and obtained a map of mara density at a resolution of four km2. We estimated an overall density of 0.93 maras.km−2 for the prediction area of 3,476 km2. The location of ranch buildings, indicators of human presence, had a strong positive effect on the abundance of maras, while the significant contribution of the geographic longitude suggested that mara density increases with higher rainfall. Although human presence favored mara abundance, presumably by providing protection against predators, it is likely that the association could bring negative consequences for maras and other species. The use of spatial models allowed us to provide the first estimate of mara abundance at a landscape scale and its spatial variation at a high resolution. Our approach can contribute to the assessment of mara population abundance and the factors shaping its spatial structure elsewhere across the species range, all crucial attributes to identify and prioritize conservation actions.

Takhtajan's floristic regions and foliicolous lichen biogeography: a compatibility analysis

2003 ◽  
Vol 35 (1) ◽  
pp. 33-53 ◽  
Author(s):  
Robert Lücking
Keyword(s):  
Large Scale ◽  
New Caledonia ◽  
Vascular Plant ◽  
Distribution Patterns ◽  
Plant Distribution ◽  
Sufficient Information ◽  
East African ◽  
Foliicolous Lichens ◽  
North East ◽  
Compatibility Analysis

AbstractTakhtajan's floristic regions of the world, based on vascular plant distribution, were used for a comparative analysis of foliicolous lichen biogeography. Of the 35 regions distinguished by that author, 23 feature foliicolous lichens. The South-East African, Fijian, Polynesian and Hawaiian regions lack sufficient information and were excluded from further analysis. Using multi-dimensional scaling and cluster and cladistic analyses, the remaining 19 regions were grouped into six lichenogeographical regions: (1) Neotropics, (2) African Paleotropics (including Madagascar, Réunion and Seychelles), (3) Eastern Paleotropics (including North-East Australia and New Caledonia), (4) Valdivian region (temperate rainforest in southern South America), (5) Tethyan region (subtropical areas of Macaronesia, Mediterranean, and Western Irano-Turanian) and (6) Neozealandic-Tasmanian region (temperate rainforests of New Zealand and Tasmania). Affinities between these six large scale regions, with 57–77% shared species, are still stronger than those between the 35 smaller scale regions denned by Takhtajan [(20−)40–60(−75)% shared species]. Based on presence/absence within each of the six regions, 22 potential distribution patterns were defined for foliicolous lichens. Many species are widely distributed; 21% are cosmopolitan or pantropical, while 19% are disjunct on at least two continents, and only 60% are restricted to one of the three major tropical areas (nearly 100% in vascular plants). Most of the latter are found in the Neotropics, while the African Paleotropics are poor in endemics. Most genera deviate significantly from overall distribution patterns; for example, Strigula and Calopadia have higher proportions of widely distributed species, while Porina displays a concentration of Eastern Paleotropical endemics. Species diversity and composition of the six regions indicate that the three extra-tropical foliicolous lichen biotas (Valdivian, Tethyan, Neozealandic-Tasmanian) are the result of partly separate evolutionary histories. On the other hand, there is a strong affinity between the Neotropics and the African Paleotropics, suggesting a shared Western Gondwanan element in the foliicolous lichen biotas of these two regions.

IMPROVING YIELD OF VEGETABLES BY USING SOILLESS MICRO-GARDEN TECHNOLOGIES IN PERI-URBAN AREA OF NORTH-EAST BRAZIL

2007 ◽  
pp. 57-65 ◽  
Author(s):  
G. Gianquinto ◽  
F. Orsini ◽  
N. Michelon ◽  
D.F. da Silva ◽  
F.D. de Faria
Keyword(s):  
Urban Area ◽  
North East

Simulation of Dynamics of Solid-Liquid Transition

1995 ◽  
Vol 407 ◽  
Author(s):  
Y. Kogure ◽  
H. Masuyama ◽  
M. Doyama
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulations ◽  
Nearest Neighbour ◽  
Neighbour Distance ◽  
Liquid Transition ◽  
Dynamics Simulations ◽  
Solid Liquid ◽  
Copper Crystals

ABSTRACTMolecular dynamics simulations on the solid-liquid transition of copper crystals have been performed. The configulation and the motion of atoms are monitored by RDF. It is seen that the height of the first peak in the RDF, which located at the nearest neighbour distance, decreased drastically as the temperature is increased.

Analysis of Seasonal Distribution Patterns of Young Largemouth Bass (Micropterus salmoides) by Use of Frequency-of-Capture Data

1976 ◽  
Vol 33 (11) ◽  
pp. 2427-2432 ◽  
Author(s):  
Michael J. Van Den Avyle
Keyword(s):  
Largemouth Bass ◽  
Micropterus Salmoides ◽  
Distribution Patterns ◽  
Seasonal Distribution ◽  
Population Estimates ◽  
Bivariate Model ◽  
Animal Populations ◽  
Terrestrial Animal ◽  
And Migration ◽  
One Year

Frequency-of-capture data indicated that behavioral patterns of tagged age II largemouth bass (Micropterus salmoides) influenced catchability with shoreline electrofishing so that midsummer population estimates were too low. The population separated into offshore and shoreline groups during the summer, and there is evidence of persistence in habitat preference from one year to the next.Tests of catchability were based on the agreement between observed frequencies of capture and those predicted from a bivariate model that allowed mortality and migration during the study. Though frequency-of-capture data have been widely utilized in studies of terrestrial animal populations, this information has been generally ignored by fishery biologists.

Struktur von Schmelzen aus dem System Wismut-Antimon mittels Neutronenbeugung

1976 ◽  
Vol 31 (1) ◽  
pp. 90-101 ◽  
Author(s):  
Peter Lamparter ◽  
Siegfried Steeb ◽  
Walter Knoll
Keyword(s):  
Neutron Diffraction ◽  
Coordination Number ◽  
Covalent Binding ◽  
The Other ◽  
Nearest Neighbour ◽  
Neighbour Distance ◽  
The Mean ◽  
The One ◽  
Subsidiary Maxima ◽  
Versus Concentration

Neutron diffraction work (λ = 0.695 Å) was done with molten Bi-Sb-alloys in the temperature range between 550 and 750 °C. Furthermore molten Bi was investigated at 300 °C. The interference functions show subsidiary maxima especially for alloys with higher Sb-concentrations. Evaluation yields, that the melts contain two different kinds of structure:a) The one kind shows coordination number 9 and a statistical distribution of the atoms of two components. This kind is more inetal-like.b) The other kind shows coordination number 3, consists of non-centered tetrahedra with smaller nearest neighbour distance. It shows covalent binding.In molten Sb the nearest neighbour distance amounts up to 3.16 - 3.19 Å for theo ne kind and up to 2.64 -2.78 Å fort he other kind, which yields an mean distance of 2.99 Å, which was observed. The dependence of the concentration of the statistical kind of meld, of the (Sb)4-, and the (Bi)4-kind from the concentration of the whole melt is given.By the model described the run of the measured mean coordination number and the mean distance versus concentration can be well explained.

Comparison of Certain Local Pseudopotentials and a New Proposal

2013 ◽  
Vol 665 ◽  
pp. 70-73
Author(s):  
Smruti J. Patel ◽  
A.Y. Vahora ◽  
B.Y. Thakore ◽  
Ashvin R. Jani
Keyword(s):  
Phonon Dispersion ◽  
Liquid Metals ◽  
Form Factors ◽  
Model Potential ◽  
Test Case ◽  
Nearest Neighbour ◽  
Core Radius ◽  
Phonon Dispersion Curves ◽  
Neighbour Distance

A new proposal of a local pseudopotential is put forwarded here depending on the concept of extended core radius in which half of the nearest neighbour distance is treated as effective core radius. There is no input of any property for fitting this parameter in this formalism. This pseudopotential is found to satisfy all the necessary requirements for applications. With this model potential we have evaluated the form factors for several bcc, fcc and hcp metals and achieved excellent agreement with previous results. On the same footing, we have examined other 14 local pseudo potentials also and on the basis of the comparison, the presently proposed pseudopotential is found to be much better. As a test case study, we have evaluated phonon dispersion curves of some liquid metals, viz. Na (Z = 1), Mg (Z = 2), Al (Z= 3) and Pb (Z = 4) and obtained quite satisfactory results.

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