Necrophagous flies assemblages: Spatio-temporal patterns in a Neotropical urban environment

Species composition, richness, and relative abundance of the communities of Calliphoridae, Muscidae, and Fanniidae in Córdoba city, Argentina was assessed, and how these characteristics are affected by seasonal and anthropogenic conditions was studied. The study was carried out in thirteen sites with various levels of urbanization during 2014 and 2015, comparing two seasons: the warmer-wet summer and the cold-dry winter. Adult flies were collected in each site using two traps baited with hydrated bone meal. A total of 1683 flies were collected, belonging to twelve genera and 22 species. Several of the species collected are relevant to forensic sciences. The most frequent species were Hydrotaea aenescens (Muscidae) and Fannia fusconotata (Fanniidae). No differences in necrophagous fly richness or relative abundances between the central urban sites and the periphery suburban sites were observed; however, richness was significantly correlated with local (250 m buffer area) built-up density. Species composition differed between the urban and suburban sites. Seasonal differences were also detected: the relative abundances per species were more even in the summer. Dissimilarities in the assemblages were mainly due to differences in the relative abundances of some species, reflecting their adaptability to landscapes with different degree of urbanization. Regardless of season or urbanization density, species richness and effective number of species were higher in traps placed in the sun as opposed to shade. Taken together, these results suggest that in Córdoba city both landscape and local factors explain variations in the necrophagous fly community.

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Species composition and spatio-temporal variation of bycatch from mid-water trawlers operating in the Arabian Sea along north-west coast of India

Regional Studies in Marine Science ◽

10.1016/j.rsma.2021.101692 ◽

2021 ◽

Vol 43 ◽

pp. 101692

Author(s):

P. Abdul Azeez ◽

Prathibha Rohit ◽

Latha Shenoy ◽

Ashok Kumar Jaiswar ◽

Mini Raman ◽

...

Keyword(s):

Species Composition ◽

Temporal Variation ◽

West Coast ◽

Arabian Sea ◽

North West ◽

West Coast Of India ◽

Spatio Temporal

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Powerful nonstationary processes on the sun: Spatio-temporal structure and efficient particle acceleration

Geomagnetism and Aeronomy ◽

10.1134/s0016793209080015 ◽

2009 ◽

Vol 49 (8) ◽

pp. 1069-1071

Author(s):

M. A. Livshits

Keyword(s):

Particle Acceleration ◽

Temporal Structure ◽

The Sun ◽

Nonstationary Processes ◽

Spatio Temporal

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First Results from Solar Orbiter’s Energetic Particle Detector

10.5194/egusphere-egu21-15792 ◽

2021 ◽

Author(s):

Javier Rodriguez-Pacheco ◽

Keyword(s):

Energetic Particle ◽

Wide Energy Range ◽

High Temporal Resolution ◽

The Sun ◽

Particle Detector ◽

First Results ◽

Wide Energy ◽

Spatio Temporal ◽

Inner Heliosphere

<p>In this presentation, we will show the first measurements performed by EPD since the end of the commissioning phase until the latest results obtained. During these months EPD has been scanning the inner heliosphere at different heliocentric distances and heliolongitues allowing - together with other spacecraft - to investigate the&#160;spatio-temporal behavior of the particle populations in the inner&#160;heliosphere during solar minimum conditions. Solar Orbiter was launched from Cape Canaveral on February 10th, 2020, thus beginning the journey to its encounter with the Sun. Solar Orbiter carries ten scientific instruments, six remote sensing and four in situ, that will allow the mission main goal: how the Sun creates and controls the heliosphere. Among the in situ instruments, the Energetic Particle Detector (EPD) measures electrons, protons and heavy ions with high temporal resolution over a wide energy range, from suprathermal energies up to several hundreds of MeV/nucleon.</p>

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Composition and spatio-temporal variation in the density of the Brachyura (Decapoda, Pleocyemata) in the rocky substrates of an Amazonian estuary

Crustaceana ◽

10.1163/15685403-00003599 ◽

2016 ◽

Vol 89 (13) ◽

pp. 1447-1466 ◽

Cited By ~ 1

Author(s):

Priscila S. V. Nóbrega ◽

Jussara M. Martinelli-Lemos

Keyword(s):

Species Richness ◽

Species Composition ◽

Rainy Season ◽

Multivariate Analyses ◽

Temporal Distribution ◽

Homogeneous Distribution ◽

Influence Of Temperature ◽

Spatio Temporal ◽

Outer Estuary ◽

Saline Zone

The present study investigated the composition, spatio-temporal distribution, and the influence of temperature and salinity on the density of brachyurans associated with rocky substrates in an estuary of the Brazilian Amazonian coast. Specimens were collected monthly at four sites representing the two margins (profiles), zones (inner and outer estuary) and the lower and upper mediolittoral portions at each site of the Marapanim estuary. A total of 14 species were collected and multivariate analyses revealed that the species composition varied systematically between zones, margins, mediolittoral sectors and seasons, with the more saline zone, the most eroded margin, the lower mediolittoral, and the rainy season all being characterized by higher densities and a more homogeneous distribution of species. In general, high densities of brachyurans, but low species richness, and marked dominance characterized the sites. Salinity proved to play an important role in the structuring of the community.

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Solar and Stellar Dynamo Waves Under Asymptotic Investigation

International Astronomical Union Colloquium ◽

10.1017/s0252921100048028 ◽

1998 ◽

Vol 167 ◽

pp. 415-418

Author(s):

Kirill M. Kuzanyan

Keyword(s):

Magnetic Field ◽

Temporal Distribution ◽

Active Regions ◽

Magnetic Activity ◽

Dynamo Model ◽

The Sun ◽

Asymptotic Investigation ◽

Spatio Temporal ◽

Dynamo Wave ◽

The Magnetic Field

AbstractThe main magnetic activity of the Sun can be visualised by Maunder butterfly diagrams which represent the spatio-temporal distribution of sunspots. Besides sunspots there are other tracers of magnetic activity, like filaments and active regions, which are observable over a wider latitudinal range of the Sun. Both these phenomena allow one to consider a complete picture of solar magnetic activity, which should be explained in the framework of one relatively simple model.A kinematic αѡ-dynamo model of the magnetic field’s generation in a thin convection shell with nonuniform helicity for large dynamo numbers is considered in the framework of Parker’s migratory dynamo. The obtained asymptotic solution of equations governing the magnetic field has a form of a modulated travelling dynamo wave. This wave propagates over the most latitudes of the solar hemisphere equatorwards, and the amplitude of the magnetic field first increases and then decreases with the propagation. Over the subpolar latitudes the dynamo wave reverses, there the dynamo wave propagates polewards and decays with latitude. Butterfly diagrams are plotted and analyzed.There is an attractive opportunity to develop a more quantitatively precise model taking into account helioseismological data on differential rotation and fitting the solar observational data on the magnetic field and turbulence, analyzing the helicity and the phase shift between toroidal and poloidal components of the field.

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What influences COVID-19 infection rates: A statistical approach to identify promising factors applied to infection data from Germany

10.1101/2020.04.14.20064501 ◽

2020 ◽

Author(s):

Moritz Mercker ◽

Uwe Betzin ◽

Dennis Wilken

Keyword(s):

Full Potential ◽

Temporal Data ◽

Infection Rates ◽

Local Factors ◽

Mobility Data ◽

Statistical Framework ◽

Spatio Temporal ◽

Local Cell ◽

Behaviour Changes ◽

Local Variability

AbstractThe recent COVID-19 pandemic is of big and world-wide concern. There is an intense discussion and uncertainty which factors and sanctions can reduce infection rates. The overall aim is to prevent an overload of the medical system. Even within one country, there is frequently a strong local variability in both – political sanctions as well as other local factors – which may influence infection rates. The main focus of study is analysis and interpretation of recent temporal developments (infection rates). We present a statistical framework designed to identify local factors which reduce infection rates. The approach is robust with respect to the number of undetected infection cases. We apply the framework to spatio-temporal infection data from Germany. In particular, we demonstrate that (1) infection rates are in average significantly decreasing in Germany; (2) there is a high spatial variability of these rates, and (3) both, early emergence of first infections and high local infection densities has led to strong recent decays in infection rates, suggesting that psychological effects (such as awareness of danger) lead to behaviour changes that reduce infection rates. However, the full potential of the presented method cannot yet be exploited, since more precise spatio-temporal data, such as local cell phone-based mobility data, are not yet available. In the nearest future, the presented framework could be applied to data from other countries at any state of infection, even during the exponential phase of the growth of infection rates.

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Improved normalization of species count data in ecology by scaling with ranked subsampling (SRS): application to microbial communities

PeerJ ◽

10.7717/peerj.9593 ◽

2020 ◽

Vol 8 ◽

pp. e9593 ◽

Cited By ~ 1

Author(s):

Lukas Beule ◽

Petr Karlovsky

Keyword(s):

Population Structure ◽

Community Structure ◽

Species Composition ◽

Microbial Communities ◽

Count Data ◽

Alpha Diversity ◽

Shannon Index ◽

Current Standard ◽

Library Size ◽

Relative Abundances

Background Analysis of species count data in ecology often requires normalization to an identical sample size. Rarefying (random subsampling without replacement), which is the current standard method for normalization, has been widely criticized for its poor reproducibility and potential distortion of the community structure. In the context of microbiome count data, researchers explicitly advised against the use of rarefying. Here we introduce a normalization method for species count data called scaling with ranked subsampling (SRS) and demonstrate its suitability for the analysis of microbial communities. Methods SRS consists of two steps. In the scaling step, the counts for all species or operational taxonomic units (OTUs) are divided by a scaling factor chosen in such a way that the sum of scaled counts equals the selected total number of counts Cmin. The relative frequencies of all OTUs remain unchanged. In the subsequent ranked subsampling step, non-integer count values are converted into integers by an algorithm that minimizes subsampling error with regard to the population structure (relative frequencies of species or OTUs) while keeping the total number of counts equal Cmin. SRS and rarefying were compared by normalizing a test library representing a soil bacterial community. Common parameters of biodiversity and population structure (Shannon index H’, species richness, species composition, and relative abundances of OTUs) were determined for libraries normalized to different size by rarefying as well as SRS with 10,000 replications each. An implementation of SRS in R is available for download (https://doi.org/10.20387/BONARES-2657-1NP3). Results SRS showed greater reproducibility and preserved OTU frequencies and alpha diversity better than rarefying. The variance in Shannon diversity increased with the reduction of the library size after rarefying but remained zero for SRS. Relative abundances of OTUs strongly varied among libraries generated by rarefying, whereas libraries normalized by SRS showed only negligible variation. Bray–Curtis index of dissimilarity among replicates of the same library normalized by rarefying revealed a large variation in species composition, which reached complete dissimilarity (not a single OTU shared) among some libraries rarefied to a small size. The dissimilarity among replicated libraries normalized by SRS remained negligibly low at each library size. The variance in dissimilarity increased with the decreasing library size after rarefying, whereas it remained either zero or negligibly low after SRS. Conclusions Normalization of OTU or species counts by scaling with ranked subsampling preserves the original community structure by minimizing subsampling errors. We therefore propose SRS for the normalization of biological count data.

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Tree species distribution in Andean forests: influence of regional and local factors

Journal of Tropical Ecology ◽

10.1017/s0266467411000617 ◽

2011 ◽

Vol 28 (1) ◽

pp. 83-95 ◽

Cited By ~ 20

Author(s):

Cecilia Blundo ◽

Lucio R. Malizia ◽

John G. Blake ◽

Alejandro D. Brown

Keyword(s):

Environmental Factors ◽

Species Composition ◽

Species Distribution ◽

Tree Species ◽

Altitudinal Gradient ◽

Local Community ◽

Climatic Factors ◽

Regional Scale ◽

Tree Species Composition ◽

Local Factors

Abstract:We identified and quantified regional and local environmental factors and spatial variation associated with tree-species composition across a 2000-m altitudinal gradient of Andean forest in north-western Argentina. A network of 47 1-ha plots was established along the altitudinal gradient within an area of about 25 000 km2; all trees ≥ 10 cm dbh were identified and measured. Constrained ordinations and variance-partitioning analyses were performed to investigate the determinants of tree-species distribution at the regional scale, across and within forest types (i.e. dry and cloud forests). We marked and measured a total of 22 240 trees belonging to 160 species. Significant environmental factors and spatial location combined accounted for 35% of total variation explained. A high proportion of variation was explained by climatic factors that were spatially structured; after removing the spatial effect, climate explained more variation in species composition across the complete gradient than did local factors. Relative importance of regional and local factors varied with geographic extent. Local factors explained more variation in tree-species composition at the within-forest scale than at the scale of the complete gradient. Our findings support the conceptual model of multi-scale controls on vegetation distribution, where local community composition and abundance result from processes at both regional and local scales.

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