scholarly journals The sustainability of indigenous lands in Amapá state

2022 ◽  
Vol 12 (3) ◽  
pp. 324-359
Author(s):  
Alcinéia Miranda Campos ◽  
Francisco Gean Freitas do Nascimento ◽  
Helenilza Ferreira Albuquerque Cunha
Keyword(s):  
Population Density ◽  
Population Growth ◽  
Essential Role ◽  
Forest Conservation ◽  
Demographic Data ◽  
Indigenous Lands ◽  
Historical Series

We herein assess population growth in indigenous lands (ILs) Wajãpi, Uaçá, Galibi and Juminã in Amapá State-Brazil, which has influenced deforestation increase. We assumed the hypothesis of no association between demographic density and deforestation because population density in these areas is low. We used population growth, deaths, and deforestation data by considering a historical series (2002-2018). Demographic data have shown that Uaçá and Wajãpi ILs recorded the highest population growth. The highest demographic density was observed for Galibi ILs and the lowest one for Wajãpi ILs. The highest deforestation was observed for Uaçá ILs and the lowest one for Juminã ILs. Therefore, indigenous lands in Amapá State have an essential role in forest conservation.

scholarly journals Structural equation modeling to shed light on the controversial role of climate on the spread of SARS-CoV-2

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alessia Spada ◽  
Francesco Antonio Tucci ◽  
Aldo Ummarino ◽  
Paolo Pio Ciavarella ◽  
Nicholas Calà ◽  
...  
Keyword(s):  
Structural Equation Modeling ◽  
Population Density ◽  
Structural Equation ◽  
Climatic Factors ◽  
Demographic Data ◽  
Factor Loading ◽  
Statistical Technique ◽  
Global Scale ◽  
Equation Modeling ◽  
Relevant Role

AbstractClimate seems to influence the spread of SARS-CoV-2, but the findings of the studies performed so far are conflicting. To overcome these issues, we performed a global scale study considering 134,871 virologic-climatic-demographic data (209 countries, first 16 weeks of the pandemic). To analyze the relation among COVID-19, population density, and climate, a theoretical path diagram was hypothesized and tested using structural equation modeling (SEM), a powerful statistical technique for the evaluation of causal assumptions. The results of the analysis showed that both climate and population density significantly influence the spread of COVID-19 (p < 0.001 and p < 0.01, respectively). Overall, climate outweighs population density (path coefficients: climate vs. incidence = 0.18, climate vs. prevalence = 0.11, population density vs. incidence = 0.04, population density vs. prevalence = 0.05). Among the climatic factors, irradiation plays the most relevant role, with a factor-loading of − 0.77, followed by temperature (− 0.56), humidity (0.52), precipitation (0.44), and pressure (0.073); for all p < 0.001. In conclusion, this study demonstrates that climatic factors significantly influence the spread of SARS-CoV-2. However, demographic factors, together with other determinants, can affect the transmission, and their influence may overcome the protective effect of climate, where favourable.

scholarly journals POPULATION ECOLOGY OF THE NORTHERN SLIMY SALAMANDER (PLETHODON GLUTINOSUS) IN EAST-CENTRAL ILLINOIS

2015 ◽  
pp. 17-21
Author(s):  
John A. Crawford ◽  
Andrew R. Kuhns ◽  
Mathys J. Meyer
Keyword(s):  
Population Density ◽  
Population Ecology ◽  
Demographic Data ◽  
Ecosystem Integrity ◽  
East Central ◽  
Plethodon Glutinosus ◽  
Capture Success ◽  
Plethodontid Salamanders ◽  
Management Plans ◽  
Central Illinois

The importance of plethodontid salamanders in forested habitats has been recognized for decades and more recently plethodontids have been touted as a model taxon for monitoring ecosystem integrity and recovery. However, basic demographic data that are crucial to conservation and management plans are currently lacking for many species and regions. The objectives of our study were to characterize the population density, biomass, and capture success of a peripheral population of Plethodon glutinosus to provide a comparison for eastern populations and set a baseline for future monitoring of Midwestern populations. We estimated the population density of P. glutinosus at our site to be 0.41 salamanders/m2, with an estimated biomass of 0.70 g/m2. We did not find any evidence for temperature or precipitation affecting capture success. Our results showed that our density estimate falls within the range of other population ecology studies of Plethodon and sets a baseline for other peripheral Midwestern populations.

scholarly journals Trends of forest area and population and the impact of population on forest area per hectare in Serbia without APS

2012 ◽  
pp. 183-196
Author(s):  
Nenad Rankovic
Keyword(s):  
Population Density ◽  
Population Growth ◽  
Forest Cover ◽  
Forest Policy ◽  
Forest Area ◽  
Economic Changes ◽  
Policy Measures ◽  
Per Capita ◽  
The Impact

Socio-economic changes throughout history have shaped the attitude towards the forest and most significant ones are changes in terms of population. Over the centuries population and population density have had a significant impact on deforestation and the reduction of forest areas. Therefore, it is important to check what kind of trends are concerned and how population growth affects forest areas, forest cover and forest area per capita. These elements are important for assessing the direction, intensity of activity and the degree of success in the implementation of all forest policy measures in Serbia.

Aging in suburban Canada

2021 ◽  
pp. 81-88
Author(s):  
Maxwell Hartt ◽  
Natalie S. Channer ◽  
Samantha Biglieri
Keyword(s):  
Population Density ◽  
Built Environment ◽  
Population Growth ◽  
Home Ownership ◽  
Operational Definition ◽  
Single Family ◽  
Family Housing ◽  
Definition Of ◽  
Commuting Patterns ◽  
Suburban Landscape

This chapter talks about Canada's built environment and population growth that predominantly occurs on the urban fringe. It describes Canada as a suburban nation and its largest metropolitan areas, which include Vancouver, Montréal, and Toronto with the suburban residents that exceed 80 percent. It also distinguishes traditional forms of suburban locations that can be characterized by a variety of factors, such as the proportion of single-family housing, car-commuting patterns, population density, and home-ownership rates. The chapter recognizes that the modern suburban landscape is complex and diverse and that there is no single perfect operational definition of suburban. It examines suburban Canada's population that is relatively heterogeneous, compared to rural locations, but is still significantly less diverse than urban Canada.

Density-Dependent Population Growth

2020 ◽  
pp. 29-46
Author(s):  
Michael J. Fogarty ◽  
Jeremy S. Collie
Keyword(s):  
Population Density ◽  
Population Growth ◽  
Density Dependence ◽  
Multiple Equilibria ◽  
Dynamical Behavior ◽  
Logistic Growth ◽  
Density Dependent ◽  
Per Capita ◽  
Discrete Time Models ◽  
Complex Dynamical Behavior

The observation that no population can grow indefinitely and that most populations persist on ecological timescales implies that mechanisms of population regulation exist. Feedback mechanisms include competition for limited resources, cannibalism, and predation rates that vary with density. Density dependence occurs when per capita birth or death rates depend on population density. Density dependence is compensatory when the population growth rate decreases with population density and depensatory when it increases. The logistic model incorporates density dependence as a simple linear function. A population exhibiting logistic growth will reach a stable population size. Non-linear density-dependent terms can give rise to multiple equilibria. With discrete time models or time delays in density-dependent regulation, the approach to equilibrium may not be smooth—complex dynamical behavior is possible. Density-dependent feedback processes can compensate, up to a point, for natural and anthropogenic disturbances; beyond this point a population will collapse.

Diagnosing declining grassland wader populations using simple matrix models

2009 ◽  
Vol 59 (1) ◽  
pp. 127-144 ◽  
Author(s):  
Lia Hemerik ◽  
Chris Klok ◽  
Maja Roodbergen
Keyword(s):  
Growth Rate ◽  
Population Growth ◽  
Matrix Models ◽  
Population Growth Rate ◽  
Adult Stage ◽  
Demographic Data ◽  
Leslie Matrix ◽  
Adult Survival ◽  
Demographic Parameters ◽  
Survival And Reproduction

AbstractMany populations of wader species have shown a strong decline in number in Western-Europe in recent years. The use of simple population models such as matrix models can contribute to conserve these populations by identifying the most profitable management measures. Parameterization of such models is often hampered by the availability of demographic data (survival and reproduction). In particular, data on survival in the pre-adult (immature) stage of wader species that remain in wintering areas outside Europe are notoriously difficult to obtain, and are therefore virtually absent in the literature. To diagnose population decline in the wader species; Black-tailed Godwit, Curlew, Lapwing, Oystercatcher, and Redshank, we extended an existing modelling framework in which incomplete demographic data can be analysed, developed for species with a pre-adult stage of one year. The framework is based on a Leslie matrix model with three parameters: yearly reproduction (number of fledglings per pair), yearly pre-adult (immature) and yearly adult (mature) survival. The yearly population growth rate of these populations and the relative sensitivity of this rate to changes in survival and reproduction parameters (the elasticity) were calculated numerically and, if possible, analytically. The results showed a decrease in dependence on reproduction and an increase in pre-adult survival of the population growth rate with an increase in the duration of the pre-adult stage. In general, adult survival had the highest elasticity, but elasticity of pre-adult survival increased with time to first reproduction, a result not reported earlier. Model results showed that adult survival and reproduction estimates reported for populations of Redshank and Curlew were too low to maintain viable populations. Based on the elasticity patterns and the scope for increase in actual demographic parameters we inferred that conservation of the Redshank and both Curlew populations should focus on reproduction. For one Oystercatcher and the Black-tailed Godwit populations we suggested a focus on both reproduction and pre-adult survival. For the second Oystercatcher population pre-adult survival seemed the most promising target for conservation. And for the Lapwing populations all demographic parameters should be considered.

scholarly journals Mazes to Study the Effects of Spatial Complexity, Predation and Population Density on Mate Finding

Insects ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 256
Author(s):  
Lloyd D. Stringer ◽  
Nicola J. Sullivan ◽  
Robyn White ◽  
Alfredo Jiménez-Pérez ◽  
Jess Furlong ◽  
...  
Keyword(s):  
Population Density ◽  
Population Growth ◽  
Habitat Complexity ◽  
Spatial Separation ◽  
Generalist Predator ◽  
Mate Finding ◽  
Testing Hypotheses ◽  
Species Establishment ◽  
3D Printed ◽  
Population Maintenance

The difficulty to locate mates and overcome predation can hamper species establishment and population maintenance. The effects of sparseness between individuals or the effect of predators on the probability of population growth can be difficult to measure experimentally. For testing hypotheses about population density and predation, we contend that habitat complexity can be simulated using insect mazes of varying mathematical difficulty. To demonstrate the concept, we investigated whether the use of 3D printed mazes of varying complexity could be used to increase spatial separation between sexes of Drosophila simulans, and whether the presence of a generalist predator hampered mate-finding. We then examined how increasing D. simulans population density might overcome the artificially created effects of increasing the distance between mates and having a predator present. As expected, there was an increase in time taken to find a mate and a lower incidence of mating as habitat complexity increased. Increasing the density of flies reduced the searching time and increased mating success, and overcame the effect of the predator in the maze. Printable 3D mazes offer the opportunity to quickly assess the effects of spatial separation on insect population growth in the laboratory, without the need for large enclosed spaces. Mazes could be scaled up for larger insects and can be used for other applications such as learning.

scholarly journals Weather influences M. arvalis reproduction but not population dynamics in a 17-year time series

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Patrick Giraudoux ◽  
Petra Villette ◽  
Jean-Pierre Quéré ◽  
Jean-Pierre Damange ◽  
Pierre Delattre
Keyword(s):  
Time Series ◽  
Population Dynamics ◽  
Population Growth ◽  
Growth Rates ◽  
Demographic Data ◽  
Common Vole ◽  
Empirical Work ◽  
Weather Conditions ◽  
Female Reproduction ◽  
Population Growth Rates

Abstract Rodent outbreaks have plagued European agriculture for centuries, but continue to elude comprehensive explanation. Modelling and empirical work in some cyclic rodent systems suggests that changes in reproductive parameters are partly responsible for observed population dynamics. Using a 17-year time series of Microtus arvalis population abundance and demographic data, we explored the relationship between meteorological conditions (temperature and rainfall), female reproductive activity, and population growth rates in a non-cyclic population of this grassland vole species. We found strong but complex relationships between female reproduction and climate variables, with spring female reproduction depressed after cold winters. Population growth rates were, however, uncorrelated with either weather conditions (current and up to three months prior) or with female reproduction (number of foetuses per female and/or proportion of females reproductively active in the population). These results, coupled with age-structure data, suggest that mortality, via predation, disease, or a combination of the two, are responsible for the large multi-annual but non-cyclic population dynamics observed in this population of the common vole.

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