Chapter 8. Nonautonomous Population Growth: Asymptotic Equality of Population Sizes

2003 ◽  
pp. 75-80
Keyword(s):  
Population Growth ◽  
Asymptotic Equality ◽  
Population Sizes

scholarly journals Re-Evaluation of World Population Figures: Politics and Forecasting Mechanics

2020 ◽  
Vol 34 (1) ◽  
pp. 104-125
Author(s):  
Olatunji Abdul Shobande ◽  
Oladimeji Tomiwa Shodipe
Keyword(s):  
Population Growth ◽  
Moving Average ◽  
Sub Saharan Africa ◽  
World Population ◽  
The Social ◽  
The World ◽  
Population Sizes ◽  
Sub Saharan ◽  
Support Programmes ◽  
Sustainable Economic Growth

AbstractThis paper forecasts the world population using the Autoregressive Integration Moving Average (ARIMA) for estimation and projection for short-range and long-term population sizes of the world, regions and sub-regions. The study provides evidence that growth and population explosion will continue in Sub-Saharan Africa, tending the need to aggressively promote pragmatic programmes that will balance population growth and sustainable economic growth in the region. The study argued that early projections took for granted the positive and negative implications of population growth on the social structure and offset the natural process, which might have implication(s) on survival rate. Given the obvious imbalance in population growth across continents and regions of the world, a more purposeful inter-regional and economic co-operation that supports and enhances population balancing and economic expansion among nations is highly recommended. In this regard, the United Nations should compel member states to vigorously and effectively implement domestic and international support programmes with this objective in view.

scholarly journals Effect of foundress population density and size on reproduction and population growth of a haplodiploid mite

2020 ◽  
Vol 25 (11) ◽  
pp. 2063-2076
Author(s):  
Nuwan Weerawansha ◽  
Qiao Wang ◽  
Xiong Zhao He
Keyword(s):  
Population Density ◽  
Population Growth ◽  
Intrinsic Rate ◽  
Adaptive Strategy ◽  
Food Competition ◽  
Intrinsic Rate Of Increase ◽  
Vegetable Crops ◽  
Rate Of Increase ◽  
Population Sizes ◽  
Pest Mite

Tetranychus ludeni Zacher (Acari: Tetranychidae) is an invasive polyphagous haplodiploid pest mite of many vegetable crops in many parts of the world. This study investigated the effects of simultaneous variations in the local foundress population density and size on the reproduction and population growth of T. ludeni. We show that negative population-density and -size dependency limited the reproduction of foundresses, where the effects of population size on population growth overweighed that of population density. We further demonstrate that ovipositing females could accelerate population growth rate (intrinsic rate of increase, rm) at higher population sizes by producing more daughters early during their lifespan, which can be an adaptive strategy to allow more daughters to complete development and disperse to reduce future food competition intensity. This study provided knowledge on population dynamics in response to foundress population density and size in general and T. ludeni population forecast and precise timing of pest management in particular.

The dynamics of collembolan populations: a matrix model of single species population growth

1977 ◽  
Vol 55 (2) ◽  
pp. 314-324 ◽  
Author(s):  
Barry C. Longstaff
Keyword(s):  
Population Growth ◽  
Matrix Model ◽  
Size Structure ◽  
Single Species ◽  
Deterministic Models ◽  
Damped Oscillations ◽  
Species Population ◽  
Population Sizes ◽  
Set Up ◽  
Single Species Population

The construction of a matrix model for the growth of populations of soil Collembola is described. Data from four replicate cultures of each of two species kept under laboratory conditions were modelled in the form of difference equations, which took into account the size structure of the populations. These equations were set up so as to effect a Leslie-type matrix model. The effect of density upon population growth rate was incorporated into the model in the form of a density-related function for fecundity.The success of the modelling procedures was varied with some of the models accurately predicting both the pattern of population growth and the population sizes at successive time intervals, whilst others only showed the trends. The deterministic models of each of the replicates for each species were combined to produce a stochastic model for that species. These also met with mixed success. The equilibrium values for the deterministic models were calculated and their stability properties examined. The models for both species predict a stable equilibrium approached by a series of damped oscillations.

On Population Growth of Cities in a Region: A Stochastic Nonlinear Model

1982 ◽  
Vol 14 (5) ◽  
pp. 585-590 ◽  
Author(s):  
P K Sikdar ◽  
P K Karmeshu
Keyword(s):  
Population Dynamics ◽  
Differential Equations ◽  
Population Growth ◽  
Time Evolution ◽  
Nonlinear Model ◽  
Planck Equation ◽  
Migration Model ◽  
Coupled Differential Equations ◽  
State Dependent ◽  
Population Sizes

A stochastic migration model describing the population dynamics in a region is investigated. The model is described by a pair of coupled differential equations with state-dependent stochasticity. Explicit expressions for the time evolution of the moments for the population sizes of cities are obtained from the Fokker-Planck equation. The Stratonovich calculus is employed in the analysis.

İstanbul İlçelerinin Nüfus Değişimi ve Kütük Bilgilerinin Analizi

2019 ◽  
Vol 6 (1) ◽  
pp. 37-72
Author(s):  
Ulaş Sunata ◽  
Dila Ergül
Keyword(s):  
Population Growth ◽  
Population Growth Rate ◽  
Population Change ◽  
Urban Migration ◽  
Specific Population ◽  
Related Factors ◽  
Internal Migrant ◽  
Level Analysis ◽  
Study District ◽  
Demographic Features

39 ilçesiyle Türkiye’nin en büyük nüfusuna sahip ili İstanbul aynı zamanda Türkiye’nin en çok iç göç alan şehridir. Özellikle kırdan kente göç bağlamında sosyo-ekonomik ve demografik özellikleriyle birçok araştırmaya konu olmuştur. Fakat İstanbul yerleşik nüfusunun Türkiye’nin diğer şehirlerine kayıtlı olma yoğunluğu da önemlidir. Bu çalışmanın amacı 2012 ve 2017 yıllarındaki nüfus değişimini göz önünde bulundurarak İstanbul ilçelerinin ayrıntılı nüfus yoğunluğu ve büyüme analizini yapmak, ilgili faktörleri değerlendirmek, hemşehri ağlarını okumak adına yerleşik nüfus kütük bilgileri bakımından inceleyerek elde edilen örüntüler doğrultusunda ilçe tipolojileri oluşturmaktır. Çalışmanın birinci bölümünde ilgili beş yıllık nüfus değişimlerine göre İstanbul ilçe nüfusları analiz edilmiştir. Ardından her bir ilçe için nüfusa kayıtlı olunan kente göre nüfus büyüme hızlarına bakılarak ilçelerin ağırlıklı olarak barındırdığı hemşehri ağları belirlenmiştir. İkinci bölümde ise ilçeler nüfus değişim özelliklerine göre belirli kategorilere ayrılmış ve bu kategoriler doğrultusunda ilçe tipolojileri oluşturulmuştur..ABSTRACT IN ENGLISHA District Level Analysis of Istanbul’s Population Change (2012-2017)Istanbul having the largest population of Turkey with its 39 districts is the most internal-migrant-receiving city in Turkey. Particularly in the context of rural-to-urban migration, Istanbul has been became a subject of various researches with its socio-economic and demographic features. However, the density of Istanbul’s settled population who registered other cities of Turkey is important. The main aim of this study is to analyse population growth of all districts considering the population change between 2012 and 2017, to evaluate the related factors and to develop a district typology by using the data of settled population according to their family registration in the name of reading the current countryman networks. In the first section of the study, district populations of Istanbul are examined regarding the related five-year change. Afterwards, most repeated countryman networks of all Istanbul’s districts are specified regarding the population growth rate of the registered cities. In the latter section of the study, districts were divided into categories regarding the specific population change features which help to create district typology.

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