Colony size affects breeding density, but not spatial distribution type, in a seabird

2020 ◽  
Vol 31 (5) ◽  
pp. 1113-1119 ◽  
Author(s):  
Sandra Bouwhuis ◽  
Felix Ballani ◽  
Marie Bourgeois ◽  
Dietrich Stoyan
Keyword(s):  
Spatial Distribution ◽  
Density Dependence ◽  
Colony Size ◽  
Decision Rules ◽  
Variable Density ◽  
Breeding Density ◽  
Fine Scale ◽  
Nest Distribution ◽  
The Social ◽  
Distribution Type

Abstract The spatial distribution of individuals within populations can result in fine-scale density dependence and affect the social environment that is encountered. As such, it is important to quantify within-population spatial structuring and understand the factors that shape it. In this study, we make use of point process statistics to test whether colony size affects the statistical type of spatial nest distribution produced by common terns (Sterna hirundo) breeding at identical manmade rectangular and homogeneous islands of fixed physical size. Comparing subcolonies of variable density both within and across years, we find that inter-nest distances are smaller at higher local and overall breeding density, but that the spatial distribution type does not vary across the observed densities. This suggests that the birds’ main settlement rules do not depend on density. In our case, analyses of fine-scale density dependence or potential social effects therefore do not need to account for between-individual heterogeneity in settlement decision rules or acceptance of these rules. We urge, however, other studies to similarly test for density dependence of the spatial distribution of individuals before undertaking such “downstream” analyses.

scholarly journals Spatio-temporal distribution patterns of Plutella xylostella (Lepidoptera: Plutellidae) in a fine-scale agricultural landscape based on geostatistical analysis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jian-Yu Li ◽  
Yan-Ting Chen ◽  
Meng-Zhu Shi ◽  
Jian-Wei Li ◽  
Rui-Bin Xu ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Plutella Xylostella ◽  
Agricultural Landscape ◽  
Seasonal Pattern ◽  
Distribution Patterns ◽  
Geostatistical Analysis ◽  
Distribution Model ◽  
Detailed Knowledge ◽  
Fine Scale ◽  
Spatio Temporal

AbstractA detailed knowledge on the spatial distribution of pests is crucial for predicting population outbreaks or developing control strategies and sustainable management plans. The diamondback moth, Plutella xylostella, is one of the most destructive pests of cruciferous crops worldwide. Despite the abundant research on the species’s ecology, little is known about the spatio-temporal pattern of P. xylostella in an agricultural landscape. Therefore, in this study, the spatial distribution of P. xylostella was characterized to assess the effect of landscape elements in a fine-scale agricultural landscape by geostatistical analysis. The P. xylostella adults captured by pheromone-baited traps showed a seasonal pattern of population fluctuation from October 2015 to September 2017, with a marked peak in spring, suggesting that mild temperatures, 15–25 °C, are favorable for P. xylostella. Geostatistics (GS) correlograms fitted with spherical and Gaussian models showed an aggregated distribution in 21 of the 47 cases interpolation contour maps. This result highlighted that spatial distribution of P. xylostella was not limited to the Brassica vegetable field, but presence was the highest there. Nevertheless, population aggregations also showed a seasonal variation associated with the growing stage of host plants. GS model analysis showed higher abundances in cruciferous fields than in any other patches of the landscape, indicating a strong host plant dependency. We demonstrate that Brassica vegetables distribution and growth stage, have dominant impacts on the spatial distribution of P. xylostella in a fine-scale landscape. This work clarified the spatio-temporal dynamic and distribution patterns of P. xylostella in an agricultural landscape, and the distribution model developed by geostatistical analysis can provide a scientific basis for precise targeting and localized control of P. xylostella.

scholarly journals COVID-19 and Changes in Social Habits. Restaurant Terraces, a Booming Space in Cities. The Case of Madrid

Mathematics ◽  
2021 ◽  
Vol 9 (17) ◽  
pp. 2133
Author(s):  
Virgilio Pérez ◽  
Cristina Aybar ◽  
Jose M. Pavía
Keyword(s):  
Spatial Distribution ◽  
Social Behaviour ◽  
Local Governments ◽  
Positive Response ◽  
The Public ◽  
Outdoor Spaces ◽  
The Social ◽  
Hospitality Sector ◽  
Social Habits ◽  
The City

The COVID-19 pandemic and the fear experienced by some of the population, along with the lack of mobility due to the restrictions imposed, has modified the social behaviour of Spaniards. This has had a significant effect on the hospitality sector, viewed as being an economic and social driver in Spain. From the analysis of data collected in two of our own non-probabilistic surveys (N ~ 8400 and N ~ 2000), we show how, during the first six months of the pandemic, Spaniards notably reduced their consumption in bars and restaurants, also preferring outdoor spaces to spaces inside. The restaurant sector has needed to adapt to this situation and, with the support of the authorities (regional and local governments), new terraces have been allowed on pavements and public parking spaces, modifying the appearance of the streets of main towns and cities. This study, focused on the city of Madrid, analyses the singular causes that have prompted this significant impact on this particular city, albeit with an uneven spatial distribution. It seems likely that the new measures will leave their mark and some of the changes will remain. The positive response to these changes from the residents of Madrid has ensured the issue is being widely debated in the public arena.

scholarly journals Edelmetallgegenstände als Quellen zu sozialen Prozessen der Spätawarenzeit (8.–9. Jahrhundert n. Chr.)

2021 ◽  
Vol 72 (2) ◽  
pp. 417-452
Keyword(s):  
Spatial Distribution ◽  
Precious Metal ◽  
Eighth Century ◽  
Carpathian Basin ◽  
Early Medieval ◽  
High Quality ◽  
Cultural Changes ◽  
Archaeological Material ◽  
Metal Artefacts ◽  
The Social

Abstract The present paper analyses the precious metal artefacts, scarcely known in the huge archaeological material of the “late Avar period” (eighth to early ninth centuries AD). Unlike in the previous era the majority of the gold and silver objects of the late Avar period are stray finds; in particular high-quality goldsmith's artefacts are absent in the grave assemblages of the eighth century. The significance of precious metal objects in grave assemblages reached its low ebb around the middle of the late Avar period; afterwards not only new object types appeared but a new grave-horizon emerged comprising precious metal objects. This paper, based on the quality and morphology of the objects, their archaeological contexts as well as their spatial distribution, draws a conclusion concerning the social and cultural changes in the early medieval Carpathian Basin.

scholarly journals The Effect of Conspecific Density on Emergence ofLestes bipupillatusCalvert, 1909 (Odonata: Lestidae)

2014 ◽  
Vol 2014 ◽  
pp. 1-3 ◽  
Author(s):  
Ricardo Cardoso-Leite ◽  
Gabriel C. Vilardi ◽  
Rhainer Guillermo-Ferreira ◽  
Pitágoras C. Bispo
Keyword(s):  
Population Dynamics ◽  
Density Dependence ◽  
Social Environment ◽  
Growth Rates ◽  
High Density ◽  
Conspecific Density ◽  
Simulated Environments ◽  
The Social ◽  
Emergence Date

Conspecific density may influence adult recruitment and consequently population dynamics. Several studies have shown the density dependence of larvae growth rates in Odonata. However, few studies studied how conspecific density influence final instar larvae emergence date decisions. Considering that larvae may choose the date of emergence, the present study investigated if density affects larvae choice. For this, we reared eight final instar larvae in individual aquaria and other 24 larvae in aquaria with three larvae each. This way, we simulated environments with low and high larval densities. We then noted the days that larvae took to emerge and compared it between low and high density groups. The results showed that larvae seem to emerge earlier when in high densities (Mann-Whitney,U=10.000,P=0.03). These results support the hypothesis that damselfly last instar larvae may postpone or hasten emergence in response to the social environment and related constraints.

The relation between colony size, breeding density and ectoparasite loads of adult European bee-eaters (Merops apiaster)

Ecoscience ◽  
1998 ◽  
Vol 5 (2) ◽  
pp. 156-163 ◽  
Author(s):  
Herbert Hoi ◽  
Alzbeta Darolova ◽  
Christine König ◽  
Jàn Kristofík
Keyword(s):  
Colony Size ◽  
Breeding Density ◽  
Merops Apiaster

scholarly journals Mapping the Nepali NGO Sector: Understanding the evolutionary patterns

2019 ◽  
Vol 2 (2) ◽  
pp. 72-89
Author(s):  
Dipendra K.C. ◽  
Tippawan Lorsuwannarat
Keyword(s):  
Spatial Distribution ◽  
Social Welfare ◽  
Foreign Aid ◽  
Descriptive Statistics ◽  
Uneven Distribution ◽  
Evolutionary Patterns ◽  
Management Platform ◽  
The Social ◽  
Ministry Of Finance ◽  
Development Outcomes

The number of Nepali NGOs is on the rise. However, except the total number of NGOs, the information about the spatial distribution of these NGOs is rarely available. This descriptive paper utilizes the data from the Social Welfare Council and Aid Management Platform of the Ministry of Finance to explore the spatial distribution of NGOs and foreign aid in Nepal. It uses descriptive statistics and visual graphs and charts to demonstrate the distribution. The study finds that NGOs and foreign aid are agglomerated in province number three of Nepal. The paper suggests that the uneven distribution of NGOs and aid leads to uneven realization of development outcomes in Nepal. Registration, renewal, and procedures are extremely lengthy and tedious in Nepal.

scholarly journals Analyzing Spatial Congruencies and Mismatches between Supply, Demand and Flow of Ecosystem Services and Sustainable Development

2019 ◽  
Vol 11 (8) ◽  
pp. 2227 ◽  
Author(s):  
Uta Schirpke ◽  
Lukas Egarter Vigl ◽  
Erich Tasser ◽  
Ulrike Tappeiner
Keyword(s):  
Sustainable Development ◽  
Spatial Distribution ◽  
Ecosystem Services ◽  
Hot Spots ◽  
Sustainable Development Goals ◽  
Hot Spot ◽  
Economic Benefits ◽  
The Social ◽  
Planning Processes ◽  
Development Goals

Ecosystem services (ESs) are increasingly included into decision-making to achieve Sustainable Development Goals (SDGs). Although both concepts consider the interactions between humans and the environment, spatial relationships between ESs and sustainability have been rarely addressed. Therefore, this study aims at analyzing spatial congruencies and mismatches between ESs and sustainability in the greater Alpine region. Using hot spot and overlap analyses, we overlaid maps of supply, demand and flow of eight key ESs with the spatial distribution of sustainability based on 24 indicators. Our results reveal that, in most cases, supply of and demand for ESs are greatly dislocated. These mismatches are reflected also in the spatial distribution of sustainability. In contrast to ES demand hot spots, supply hot spots are generally characterized by high sustainability levels, especially in relation to the environment. However, due to discrepancies in the social and economic dimensions, it cannot be assumed that ES supply hot spots always correspond to high sustainability. Hence, using ES indicators for measuring sustainability provides rather limited insights. We conclude that both concepts should be applied in a complementary way to maximize ecological, social and economic benefits in land management and planning processes.

scholarly journals A Classification Model to Evaluate the Security Level in a City Based on GIS-MCDA

2016 ◽  
Vol 2016 ◽  
pp. 1-10 ◽  
Author(s):  
Ciro José Jardim de Figueiredo ◽  
Caroline Maria de Miranda Mota
Keyword(s):  
Social Dynamics ◽  
Decision Rules ◽  
Classification Model ◽  
Security Level ◽  
Previous Knowledge ◽  
Preference Information ◽  
The Social ◽  
Multicriteria Method ◽  
Spatial Environment ◽  
The City

The aim of this paper is to map the most favorable locations for the occurrence of robberies in the Brazilian city through the multicriteria method Dominance-Based Rough Set Approach. Considering the city divisions with alternatives and evaluating by several spatial criteria, a decision-maker is building a preference model with based previous knowledge. Next, decision rules induced from preference information are introduced to the spatial environment to get the results. The decision rules can be seen as conditional part (represented by criteria) and decision part (assignment to decision classes). The rules classify all the alternatives according to security level. Moreover, the rules help to understand the social dynamics of the city and to assist in the proposition of strategies against violence.

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