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Population projections rely on one-sex renewal models. Consequently, changing the projection of male mortality does not affect the projection of birth, contradicting commonsense. A two-sex renewal model is presented in this paper to provide a better description of reproduction and more reasonable population projections. This model is nonlinear and includes the one-sex renewal models as special cases. In this model, age-specific birth rates are defined for two sexes jointly; total fertility, net reproduction rate, and intrinsic growth rate are also derived for two sexes jointly; and age-specific populations approach or converge to stable status. Applying the two-sex renewal model to Australia, it indicates that one-sex models underestimated the intrinsic growth rate by 14 percent. Compared to the results of one-sex models, the two-sex model would provide higher growth rate for low-fertility countries, and lower growth rate for high-fertility countries. In other words, the one-sex models are commonly biased. If the two-sex model is applied to all the countries, it would project smaller populations for the world in the future. • A two-sex renewal model is presented to provide population projections. [ABSTRACT FROM AUTHOR]

After reaching historically low levels among the women born in the early 1940s, childlessness has been increasing in most Western countries among women born in the 1950s and 1960s. This increase took place as patterns of transition to adulthood have become increasingly late, protracted, and complex. Yet, it is precisely those women who enter a first relationship late, spend more time as single, and experience union instability who more often remain childless. This suggests that levels of childlessness will continue to increase as younger cohorts complete their childbearing histories. In this study, we use microsimulation to project the household and union formation histories of cohorts of Dutch women born between 1971 and 2000. Results suggest that childlessness will actually decrease among cohorts born between 1971 and 1983 and then increase among those born between 1984 and 2000. The decrease occurs as pathways of household and union formation become later, more protracted, and more complex, but also as cohabiting women start to exhibit a higher propensity to become mothers. The increase, on the other hand, occurs as pathways become somewhat less protracted and complex, but also as the propensity of cohabiting women to become mothers returns to previous levels and as age at leaving the parental home strongly rises. Childlessness levels appear to increasingly depend on the childbearing decisions of cohabiting couples and on age at leaving the parental home. [ABSTRACT FROM AUTHOR]

Introduction: The process of demographic transition has led to a change in the age of populations. Almost all countries around the globe have passed or are passing through the reproductive phase, which naturally contributes to the rising elderly populations. The present study was conducted to predict future trends of the elderly population in Ilam city. Materials and Methods: The secondary analysis method, population forecasting model, and scenario producing approach were used to assess demographic changes. Data analysis and the prediction of population features were performed using Spectrum and Mortpak software. Results: Among the important findings of this study was that the elderly population is rising in Ilam. Currently, the elderly population comprises 5% of the total population of Ilam, which will increase to more than 20% in 2050. Conclusion: Policy makers and managers should consider implementing social welfare and health care services for the elderly in the future. [ABSTRACT FROM AUTHOR]

For species inhabiting areas at the limit of their environmental tolerance, extreme events often drive population persistence. However, because extreme events are uncommon, their effects on population dynamics of expanding species are poorly known. We examined how extreme climate events in winter and summer affected three populations of wild turkeys occupying a natural climate gradient at the northern edge of their range. First, we examined the mechanism by which vital rates affect the population growth rate. Second, we developed a climate-dependent structured population model. Finally, by linking this population model to IPCC-class climate projections, we projected wild turkey population abundance in response to the frequency of extreme snow events by 2100 for the northernmost population. We showed that the population dynamics of the three populations is driven through different pathways expected from the theory of invading population dynamics; that those populations were mainly limited by heavy snow that decreases winter survival by restraining food access; and that a population of immigrant is projected to decline at the northern species range. This study exemplifies how extreme events affect population dynamics and range expansion of temperate species at the northern edge of the distribution. [ABSTRACT FROM AUTHOR]

Population ageing in the EU28 is an important twenty-first century phenomenon, affecting virtually every aspect of life in these countries. The results of the latest EUROPOP2018 population forecast indicate that the rate of ageing is accelerating. The aim of this paper is to analyse the current level of population ageing in the EU28, identify spatial differences, and point to likely trends by the middle of this century. For these purposes, we have used a combination of conventional chronological indicators of population ageing and a set of new indicators based on prospective age that allows for a more comprehensive and realistic view of population ageing. We use multivariate statistical methods (factor and cluster analysis) to identify groups of countries with similar population ageing characteristics, using both a retrospective and prospective approach. We decompose changes in selected ageing indicators into the separate effects of changes in the population composition (children under 15, working-age population, elderly). We then identify the effect of major demographic factors (migration, mortality, cohort turnover) for the set of EU28 countries

Projection of population in a small area is essential for the government to design proactive policies to support a variety of planning processes and making decisions. The private sector can use this information to do customer demand forecasting and market site targets on a small scale. However, most developing countries do not have this level of data for the development of small area population estimation models. The thrust of this study is to develop a linear regression-based small area population estimation model using recent census data of Metro Manila. The R2values of the developed population and household estimation models are 0.975 and 0.994, respectively, while the respective mean absolute errors (MAEs) are 9.76% and 7.98%. The developed models were then applied to project as mall area population. The area of Metro Manila with a population density of more than 50,000 persons/km2will increase from5.78% in 2010 to 9.23% in 2020, 15.14% in 2030, 21.76% in 2040, and 31.31% in 2050. The projected population within Metro Manila will increase from 11.89 million in 2010 to 29.16 million in 2050, with an average annual growth rate of 3.63% from 2010 to 2050.During this time, the population density will rise from 19,137 persons/km2in 2010 to 49,243 persons/km2in 2050. The total number of households is projected to increase from 2.89 million in 2010 to 7.49 million in 2050, which is a 2.59-fold increase.

Alpine plants are likely to be particularly vulnerable to climate change because of their restricted distributions and sensitivity to rapid environmental shifts occurring in high-elevation ecosystems. The well-studied Haleakalā silversword (‘āhinahina, Argyroxiphium sandwicense subsp. macrocephalum) already exhibits substantial climate-associated population decline, and offers the opportunity to understand the ecological and demographic mechanisms that underlie ongoing and predicted range shifts. We use nearly four decades of demographic monitoring for this threatened Hawaiian species, in combination with other biological, ecological and climate data to explore demographic responses across its entire range. We construct and independently validate population models for two elevation zones representing the species’ lower trailing and higher stable regions. Differences in population growth rate (lambda) between trailing and stable regions were influenced most strongly by lower survival of juvenile and small adult size classes, as well as by lower recruitment and lower survival of seedlings and large adults in the trailing region. Furthermore, seed production appears to have decreased from the 1980’s to present in the trailing region, and is now significantly less than in the stable region. Lambda and several underlying vital rates were significantly associated with wetter dry season conditions in the lower trailing region, indicating water limitation. In the higher elevation stable region, in contrast, lambda and vital rates were associated with warmer air temperatures, indicating cold limitation. These contrasting demographic patterns and climate dependencies lead to a high probability of extinction over the next century in the lower region, where most plants occur, but zero probability of the same in the higher region, according to stochastic population projections. Drier future scenarios further increase the probability of extinction at low elevations. The combined results illustrate the complexity in the demographic response and future viability that can occur across the range of a single species.

Background: South Korea faces a critical challenge with its rapidly declining fertility rates and an increasingly aging population, which significantly impacts the country's blood supply and demand. Despite these nationwide trends, regional disparities in blood supply and demand have not been thoroughly studied., Methods: This research utilized blood donation data from the Korean Red Cross and blood transfusion data from the Health Insurance Review and Assessment Service. We analyzed these datasets in conjunction with regional population projections to simulate blood supply and demand from 2021 to 2050 across South Korea. Sensitivity analyses were conducted to assess the impact of various factors, including the number of donors, age eligibility criteria for donations, frequency of donations, and blood discard rates., Results: Our projections indicate a decreasing trend in blood supply, from 2.6 million units in 2021 to 1.4 million units by 2050, while demand is expected to peak at 5.1 million units by 2045 before declining. Metropolitan areas, particularly Gyeonggi Province, are projected to experience the most severe shortages. Sensitivity analyses suggest that increasing the donation frequency of existing donors and relaxing age eligibility criteria are more effective strategies in addressing these imbalances than merely increasing the number of new donors. Blood discard rates showed minimal impact on the overall blood shortage., Conclusion: The findings emphasize the urgent need for targeted strategies to mitigate national and regional blood supply shortages in South Korea. Encouraging frequent donations from experienced donors and broadening eligibility criteria are critical steps toward stabilizing the blood supply amidst demographic shifts. These strategies must be prioritized to address the impending regional disparities in blood availability., Competing Interests: The authors have no potential conflicts of interest to disclose., (© 2024 The Korean Academy of Medical Sciences.)

Background: Brazil experienced a significant change in life expectancy at birth in the 20th century. In this process, it is important to observe not only the decrease in mortality level and the increase in life expectancy, but also the change in mortality pattern, that is, how mortality occurred and which ages were most impacted. Recently, these changes in the mortality pattern at more advanced ages and their impact on population aging have been discussed more intensively. However, in Brazil, discussions about human longevity and mortality behavior in advanced ages are still incipient. Experts suggest that future studies and mortality projections incorporate new trends in decelerating mortality at advanced ages and explore cohort approaches in their trend formulations. Objective: To study the effect of changes in mortality and life expectancy on predicting the elderly population size in the state of Sao Paulo, Brazil. Method: Extended cohort-component study. Results: Changes in the level and pattern of mortality have a greater effect on the population aged =80 compared with that on the population aged =60. In addition, considering the life expectancy gap between sexes is relevant to determine the future number of older people. Conclusion: The extended cohort component method is an interesting methodological approach to assess the impact of mortality changes on the elderly population projection by using different stages of the epidemiological transition as a future scenario. [ABSTRACT FROM AUTHOR]

Specific ethnocentric international migration processes can be observed in Hungary: a significant proportion of immigrants are of Hungarian ethnic background and come from neighboring countries. Similar processes can be observed between other kinstates and co-ethnic communities of Central and Eastern Europe, but this type of migration has not been studied intensively yet. The focus of the research is on the effects of this immigration on Hungarian society and the economy. Population projections were also carried out according to two research questions: "what would have happened if the immigrants had not arrived according to the processes that were experienced?" and "what will happen if the immigration process changes?" The research is based on the 2011 census data sets; the target group is the population born in neighboring countries that moved to Hungary after 1985. Results show that the ethnic Hungarian immigrant population has been a crucial human resource in Hungary. Without these immigrants, Hungary's demographic trends would also be less favorable. Moreover, in contrast to the situation typical of European immigrants, the socio-economic situation of the former is more favorable than of the host society. Potential decline of this immigration population could indeed be challenging. [ABSTRACT FROM AUTHOR]

Green peach aphid (Myzus persicae Sulzer (Aphididae: Hemiptera)) is a polyphagous pest that causes economic losses in the tobacco. In addition to general aphid damage, it is a vector for important viral diseases in tobacco. Fertilization methods, which are used to increased soil fertility, in the plant growing phase, contribute significantly to the optimal physical, chemical and biological properties of the soil, which allows the plants grown in that soil to be more resistant to diseases and pests. Therefore, in this study, the effects of liquid vermicompost and synthetic fertilizer applications on the development and biological parameters of green peach aphids were investigated in comparison with the control. The experiments were carried out under controlled climate chambers. Life table parameters were obtained using the data obtained for the development and reproduction of the aphids. In the study, while there was no statistically significant difference between population parameters, both treatments were found to suppress the pest populations compared to the control application. This application can be used as an ecological control method for the pest. [ABSTRACT FROM AUTHOR]

Purpose - The purpose of this paper is to answer the following two questions: Will Saudi Arabia get older? Will its pension system be sustainable? Design/methodology/approach - The methodology/approach is to forecast KSA’s population with wavelet analysis combined with the Burg model which fits a pt h order autoregressive model to the input signal by minimizing (least squares) the forward and backward prediction errors while constraining the autoregressive parameters to satisfy the Levinson-Durbin recursion, then relies on an infinite impulse response prediction error filter. Findings - Spectral analysis projections of Saudi age groups are more optimistic than the Bayesian probabilistic model sponsored by the United Nations Population Division: Saudi Arabia will not get older as fast as projected by the United Nations model. The KSA’s pension system will stay sustainable based on spectral analysis, whereas it will not based on the U.N. model. Originality/value - Spectral analysis will provide better insight and understanding of population dynamics for Saudi government policymakers, as well as economic, health and pension planners.

In 1972 the Canadian Armed Forces (CAF) created the Order of Military Merit (Order) to honor members who have demonstrated conspicuous merit and exceptional service. Despite efforts to ensure appointments to the Order were representative of the entire CAF, a 2007 study found that appointments had become concentrated at senior ranks. In response to this study, new nomination guidelines were released in 2007 and then augmented in 2010. The 2010 guidelines yielded some early positive results; however, the average years of service (YOS) at appointment target has not been met. The Order’s advisory council requested a population forecast of the Order to determine the impact on the size and YOS profile of the serving Order population if the typical YOS at appointment is reduced to 18 to 23 years. This paper presents the methodology used to model the Order population and discusses the impact of appointing members to the Order earlier in their career.

Frankliniella intonsa (Trybom) (Thysanoptera: Thripidae) is an important pest of numerous horticultural and agricultural crops in Taiwan. Orius strigicollis (Poppius) (Hemiptera: Anthocoridae) is a predator with high predation capacity against many pests of legumes and flowers. We used the age-stage, two-sex life table method to integrate the life table data with the predation rate of O. strigicollis fed on F. intonsa. The preadult duration, adult longevity, net reproductive rate, intrinsic rate of increase, and finite rate of increase for O. strigicollis were 13.6 d, 12.5 d, 18.8 offspring/individual, 0.1437 d-1, and 1.1546 d-1, respectively. The total predation of O. strigicollis during their preadult and adult stages was 60.4 and 107.3 thrips, respectively. The net predation rate was 101 prey/individual. To demonstrate the effect of releasing predators of different stages on the population growth and predation capacity, we used population projection to evaluate the predation potential of O. strigicollis, and the uncertainty of predation potential was determined by using the life tables from the 0.025th and 0.975th bootstrap percentiles of the finite rate of increase. Releasing third instars or adults of O. strigicollis can effectively control the pest sooner than releasing O. strigicollis eggs. In biological control, both predator and prey populations are age-stage-structured and (in most instances) individuals of both sexes are present. It is imperative that the agestage, two-sex life table be used to precisely incorporate the variability that occurs in the developmental rate, stage differentiation, survival rates, and predation rates among individuals and between sexes. Our results demonstrate that integrating life table and predation rate data generated by using the age-stage, two-sex life table is an important technique for improving biological control programs by refining the timing and estimating the release of natural enemies. Moreover, by using the multinomial theorem, we demonstrated that a large resampling (B =100,000) is necessary to obtain more precise estimates of population parameters in applications of the bootstrap technique. [ABSTRACT FROM AUTHOR]

Drought represents one of the most severe constraints to agricultural production; therefore, resistance to drought has the highest priority in the development of new cultivars. How insect pests respond to drought-resistant cultivars is poorly understood. In this study, by using the rose-grain aphid, Metopolophium dirhodum (Walker), in controlled laboratory conditions, we investigated the level of antibiosis of six commercially available cultivars of spring wheat (Triticum aestivum L.), which differed in their resistance to drought (drought-resistant cultivars: Septima, Jarissa and Seance; drought-sensitive cultivars: Quintus, Kabot and SW Kadrilj). Leaf morphological and structural traits were also measured for each cultivar to determine which leaf traits may be responsible for the observed differences. We used an age-stage, two-sex life table approach for comprehensive quantification of the aphid response to a particular cultivar and for projecting population growth. Although we found significant differences in all the life table and population growth parameters between the cultivars (SW Kadrilj was the most resistant to the aphids and Septima and Quintus were the most susceptible to the aphids), resistance to drought alone did not explain the observed variation. The cultivars also varied in most of the morphological and structural leaf traits measured. An increase in cuticle thickness at the cell junction above the major vein hampered the development of the aphid nymphs, which resulted in slower rates of population increase. Trichome density seemed to reduce the survival of the aphid nymphs. These two traits support not only drought resistance in general but also resistance to aphids and are potentially useful for selection in the future breeding of cereals. [ABSTRACT FROM AUTHOR]

The climate on our planet is changing and the range distributions of organisms are shifting in response. In aquatic environments, species might not be able to redistribute poleward or into deeper water when temperatures rise because of barriers, reduced light availability, altered water chemistry or any combination of these. How species respond to climate change may depend on physiological adaptability, but also on the population dynamics of the species.Density dependence is a ubiquitous force that governs population dynamics and regulates population growth, yet its connections to the impacts of climate change remain little known, especially in marine studies. Reductions in density below an environmental carrying capacity may cause compensatory increases in demographic parameters and population growth rate, hence masking the impacts of climate change on populations. On the other hand, climate‐driven deterioration of conditions may reduce environmental carrying capacities, making compensation less likely and populations more susceptible to the effects of stochastic processes.Here we investigate the effects of climate change on Baltic blue mussels using a 17‐year dataset on population density. Using a Bayesian modelling framework, we investigate the impacts of climate change, assess the magnitude and effects of density dependence, and project the likelihood of population decline by the year 2030.Our findings show negative impacts of warmer and less saline waters, both outcomes of climate change. We also show that density dependence increases the likelihood of population decline by subjecting the population to the detrimental effects of stochastic processes (i.e. low densities where random bad years can cause local extinction, negating the possibility for random good years to offset bad years).We highlight the importance of understanding, and accounting for both density dependence and climate variation when predicting the impact of climate change on keystone species, such as the Baltic blue mussel. [ABSTRACT FROM AUTHOR]

Bactrocera dorsalis (Hendel), as a quarantine pest in many countries and regions, has shown a trend of northward diffusion in the past century in China. In order to determine whether B. dorsalis will cause great harm to the dominant northern fruits, the age-stage two-sex life tables of peaches and apples were constructed, with oranges as the control. The results showed that the developmental rate, intrinsic rate of increase (r), and finite rate of increase (λ) on oranges and peaches were significantly greater than on apples. Additionally, the prediction of population growth 90 days after oviposition revealed that the whole population on oranges and peaches increased by 13,667.3 and 12,112.1 times, respectively, indicating that B. dorsalis is very likely to endanger peach orchards. The population increased on apples by 4311 times, though this is lower than that on oranges and peaches. Overall, peaches with high fitness similar to oranges are very suitable as a host for B. dorsalis and are likely to become a new favorable host, while apples may also become a potentially new host, though with lower fitness. Therefore, the most pressing solutions to take are population monitoring, comprehensive prevention, and control in the case of any potential large-scale outbreak of B. dorsalis in northern China.

Innovative organic control measures such as vermisuspension is one of the preferred methods in the field of organic crop cultivation, which increases yield, and is inexpensive, promotes plant growth through soil worms and various microorganisms. In this study, the effects of two different vermisuspension applications on the growth parameters of Myzus (N.) persicae Sulzer (Hemiptera: Aphididae) fed on the pepper were tested in climate rooms at 25±1°C, 65±5% RH, and a photoperiod of 16:8 (L:D) h (5000 lux) conditions. Vermisuspensions were diluted 1/100 and applied to the pots by drinking method. Life table parameters were estimated according to age-stage, two-sex life table method. As a result of the study, while there was no significant difference between two different vermisuspension applications (VS1 and VS2), VS1 application was found to be more effective than the control application. Net reproductive rate (R0) (30.87 offspring/individual), intrinsic rate of increase (r) (0.2145 d-1) and finite rate of increase (λ) (1.2393 d-1 ) values on VS1 treated plants were lower than those obtained on control plants. [ABSTRACT FROM AUTHOR]

We evaluated the direct effects of three different CO2 concentrations (400, 600 and 1,000 ppm) on the population parameters and growth of the bean bug, Riptortus pedestris, while being fed on soybean. The raw life history data from R. pedestris was analyzed using an age‐stage, two‐sex life table to take the viable development rate among individuals into account. Based on the age‐stage, two‐sex life table analysis, the population projections of R. pedestris provide the stage structure and variability of the population growth under different CO2 treatments. Our results showed significantly shorter immature durations and higher pre‐adult survival rate under elevated CO2 (1,000 ppm) than those under ambient CO2 (400 ppm). The population of R. pedestris reared under elevated CO2 conditions showed higher intrinsic and finite rates of increase but a lower mean generation time than R. pedestris reared under ambient CO2 conditions. Our results show the population parameters and growth of R. pedestris are influenced by increased CO2 relative to ambient CO2 treatment. Further studies on the long‐term direct effects of different CO2 levels on R. pedestris are essential to understand their population dynamics and to establish appropriate management strategies. [ABSTRACT FROM AUTHOR]

In this study, we determined the influence of fluctuating temperatures on the development and fecundity of the bean bug Riptortus pedestris (Fabricius) (Hemiptera: Alydidae) by collecting life table data for individuals exposed at a constant temperature (24 °C) and three fluctuating temperatures (24 ± 4 °C, 24 ± 6 °C, and 24 ± 8 °C). The raw life history data were analyzed using an age-stage, two-sex life table to take into account the viable development rate among individuals. Based on these analyses, the population projections enabled us to determine the stage structure and variability of population growth under different temperature treatments. Our results revealed shorter periods of immature development and a higher pre-adult survival rate at 24 ± 6 °C than under the other assessed temperature conditions. Furthermore, significant reductions in female longevity were recorded at 24 °C, whereas the fecundity, net reproductive rate, and intrinsic and finite rates of increase were highest at 24 ± 6 °C. These findings reveal that fluctuating temperatures have a positive influence on the life history traits of R. pedestris and indicate that observations made under constant temperatures may not explain sufficiently enough the temperature dependent biological performances of pests in the field.

Abstract A number of contemporary populations are exhibiting sustained fertility at levels substantially below long-term replacement. Nonetheless, relatively few populations are actually diminishing in size. Here, we approach that apparent paradox by analyzing the time before the number in a birth cohort, and its descendants, falls below the initial number in the cohort. First, models are examined with constant below replacement fertility, cohort extinction at age 75 or 85, and no mortality below the highest age attained. For a net reproduction rate (NRR) of 0.75, it takes 150 years for the cohort’s descendants to be fewer than the cohort’s original size if persons live to age 85, and over 130 years if persons live to age 75. If the NRR is at least 0.60, it takes a century before the descendants are fewer in number than the original cohort. Second, projections are done for the USA 2012, Italy 2012, and Hong Kong 2011 assuming that fertility and mortality remain constant. The results resemble the projections. For example, in Italy, with actual mortality and an NRR of 0.70, it takes over 125 years before the descendants of a cohort are fewer in number than the initial cohort. A relatively simple equation for the long term “time to decline” is presented, showing that it depends primarily on the level of fertility, secondarily on longevity, and only modestly on the mean age of fertility.

The life history and fitness of Nilaparvata lugens being reared under ambient level (current CO2 concentration), medially elevated (550 µL/L) and highly elevated (750 µL/L) CO2 concentration for long-term generation were compared using two-sex life table instead of traditional age-specific life table. The results showed that significantly longer larval duration and lower fecundity of N. lugens were observed in 750 µL/L relative to 550 µL/L treatment (P < 0.05). Accordingly, 550 µL/L CO2 significantly enhanced population parameters of N. lugens, including significantly higher intrinsic rate of increase (r), finite rate (λ) and net reproductive rate (RO), but not for 750 µL/L CO2. Taken together, N. lugens performs enhanced development rate, fecundity and survival in individual life history and higher potential in population multiplication under 550 µL/L CO2 level, while only indicates the less enhanced development rate and survival without significant increased capacity of population expansion under 750 µL/L CO2 level. These results should facilitate predicting the fitness and potential population damage of N. lugens, which is valuable for the integrated control of N. lugens in the future increasing CO2 concentration. [ABSTRACT FROM AUTHOR]

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This paper explores the impacts of the universal two-child policy on Beijing's population in the long term. It gives a detail estimation of Beijing population considering the latest fertility and immigration policy and can help related government department management population. The cohort-component method based on a net migration was applied to project population by age for Beijing from 2020 to 2050 in four fertility scenarios. The innovation is the estimation method of the mortality rate with the life table linked with life expectancy. The results show that, though the basic development trend of Beijing's population will not change essentially under the universal two-child policy, low birth rate and aging problems will be improved. Compared with the partial policy relaxation, the total population will be 876,478 persons more than that in 2050, the share of population aged 0–14 will increase 1.1 percentage points, and the aged dependency ratio will decrease 1.96 percentage points. Some measures should be taken to encourage more couples to have a second child and introduce more young talents to promote Beijing's prosperity. [ABSTRACT FROM AUTHOR]

Projection of population in a small area is essential for the government to design proactive policies to support a variety of planning processes and making decisions. The private sector can use this information to do customer demand forecasting and market site targets on a small scale. However, most developing countries do not have this level of data for the development of small area population estimation models. The thrust of this study is to develop a linear regression-based small area population estimation model using recent census data of Metro Manila. The R² values of the developed population and household estimation models are 0.975 and 0.994, respectively, while the respective mean absolute errors (MAEs) are 9.76% and 7.98%. The developed models were then applied to project a small area population. The area of Metro Manila with a population density of more than 50,000 persons/km² will increase from 5.78% in 2010 to 9.23% in 2020, 15.14% in 2030, 21.76% in 2040, and 31.31% in 2050. The projected population within Metro Manila will increase from 11.89 million in 2010 to 29.16 million in 2050, with an average annual growth rate of 3.63% from 2010 to 2050. During this time, the population density will rise from 19,137 persons/km² in 2010 to 49,243 persons/km² in 2050. The total number of households is projected to increase from 2.89 million in 2010 to 7.49 million in 2050, which is a 2.59-fold increase. [ABSTRACT FROM AUTHOR]

Tamarixia radiata Waterson (Hymenoptera: Eulophidea) is the principal natural enemy used for the control of the major citrus pest Diaphorina citri Kuwayama (Hemiptera: Liviidae). In this study, we collected the life-history data of T. radiata at four different temperatures (20, 27.5, 30, and 35°C) and analyzed them by using the age-stage, two-sex life table. The longest preadult developmental time (16.53 d) was observed at 20°C, whereas the shortest one was 7.29 d at 35°C. The preadult development rate was well-fitted to a linear equation. The lower threshold temperature (T 0) was 7.85°C and the thermal summation (K) was 193.36 degree-day. The highest fecundity (F) was 322.7 eggs per female was at 27.5°C, whereas the lowest one was 10.8 eggs per female at 35°C. The net reproductive rate (R 0) were 70.97, 169.42, 55.70, and 3.25 offspring at 20, 27.5, 30, and 35°C, respectively; the intrinsic rate of increase (r) were 0.1401, 0.3167, 0.3517, and 0.1143 d−1, respectively. The highest values of fecundity, net reproductive rate, intrinsic rate of increase, and finite rate of increase were observed at 27.5°C. The relationships among F , R 0, N f, and N in all treatments were consistent with R 0 = F × ( N f / N) ⁠. The age of peak reproductive value was close to the total preoviposition period in all treatments. Population projections based on the age–stage, two-sex life table showed the dynamics of stage structure and its variability. Faster population growth was observed at 27.5 and 30°C. [ABSTRACT FROM AUTHOR]

Objective: Climate change is defined by the United Nations Global Climate Change Framework Convention (UNFCCC) as a "change in the climate as a result of human activities that directly or indirectly disrupt the composition of the global atmosphere in addition to the natural climate changes observed in comparable time periods". Researchers have shown that climate changes, which have been observed to occur in geological periods, have not only changed the geography of the world, but also played a key role in the spread of ecological systems and living things. Global climate change is a different problem from all other problems due to both of its scale and its relation to the future. One of the prominent points in this difference is how existing water resources and water consumption can be affected. The focus of this research is how human water consumption can be shaped in condition of settling the growing refugee population on Turkey's geography in the last period on the basis of population data obtained previously and with the effects of climate change what kind of results can emerge in the coming years. Methods: Turkey's population and population projections related to population growth of the Syrian refugees under temporary protection are obtained from a special report; "Syrian Refugees and Demographic Projections" and top ten provinces' -which chiefly hosting these refugees-daily taken amount of water per person and 2040 projections were calculated. This hypothetical need and the water supply service planned to be presented were also compared. Subsequently, these impacts have been assessed by adding the impact scenarios of climate change on water resources which are obtained from a project carried out by General Directorate of Water Management. Results: It can be seen from the results of the research that as of 2040, the most intensive water consumption need may occur in Istanbul with 3.568.208,868 tons of m3 per day, while Gaziantep takes the second place with 1.089.147,202 tons of m3 and İzmir with 908.527,492 tons of m3. When the impact of climate change on water resources is matched with the scenarios of 2040, it is seen that the data of the provinces of Southeast Anatolian Region are at the most critical levels. Conclusion: In addition to the pressures created by climate change effects on natural resources, sudden asylum seeker or refugee movements in critical regions will lead the regions to be more vulnerable and inadequate to the climate change effects. While managing these massive human movements, the impacts on water and other resources should be calculated and the policies to be formed should be shaped in this framework. "Zero Day" calculations in terms of water resources in Turkey are urgently needed to be done at the scales of the basins and the entire land surface. [ABSTRACT FROM AUTHOR]

The present study examines the population projection of the settlements of the Balaton Region (BKÜ) by 2062, taking into account 180 settlements. The results are presented for the main age groups of the region, at five-year intervals, and broken down as follows: 18 cities, coastal villages (group of 39 settlements), and non-coastal villages (group of 123 settlements). The most recent research report on which this study is based was produced in 2017. For the two years since then, we can also identify deviations from previously forecasted processes. Using another method, we interrogate the reliability of the previous prediction. The population projection shows that the population of the resort area will fall to 184,000 by 2062, and the proportion of the population over the age of 65 will reach or even exceed 35%. In addition to the aging of the villages, the depopulation of dwarf villages further away from the coast poses a serious problem. [ABSTRACT FROM AUTHOR]

Building on the well-established knowledge on fertility differentials by education and nativity/migration status, we employ microsimulation modelling to demonstrate the effect of accounting for such differences in population projections. We consider fertility differentials by educational attainment, enrolment in full-time education, region of birth, age at immigration, and duration of stay in the host country, which we introduce step-wise into the microsimulation model for the EU28. Results on projected TFRs and births by 2060 illustrate the importance of accounting for several sources of population heterogeneity. In the context of future educational expansion, modelling education differentials for students and for women with completed education is needed to capture the postponement effect of education on childbearing. Future migration assumptions that include migrant fertility differentials lead to widely varying projected numbers of future births. At fixed fertility differentials and a fixed composition of immigrant flows, the net effect of immigrant fertility on the overall TFR in the EU28 is projected to increase from the estimated 0.12 in 2015–2019 to 0.17 in 2055–59 in the scenario with baseline migration, and to 0.25 in 2055–59 in the scenario with doubled migration. [ABSTRACT FROM AUTHOR]

The predatory mite, Neoseiulus bicaudus (Wainstein), is a potential biological control agent against spider mites and thrips. The objective of this experiment was to compare the effects of three diets on the life table of N. bicaudus. The three diets were 1) Tetranychus turkestani (Ugarov & Nikolskii) (Acari: Tetranychidae), the natural prey of N. bicaudus ; 2) Tyrophagus putrescentiae (Schrank) (Acari: Acaridae), an alternative prey; and 3) artificial diet primarily consisting of decapsulated shrimp cysts, egg yolk, and honey. The computer simulation was used to project the population growth of N. bicaudus fed on different diets. The preadult developmental time (3.83 d) of N. bicaudus was shortest, and the intrinsic rate of increase (r = 0.2782 d−1) and the net reproductive rate (R 0 = 18.98 offspring) were highest when reared on the alternative prey Ty. putrescentiae. The total development time (7.37 d) was longest, and the population parameters were the lowest (r = −0.0081 d−1, R 0 = 0.85 offspring) when N. bicaudus was reared on artificial diet. The population projection showed that the population of N. bicaudus reared on Ty. putrescentiae could increase fast. Our results showed that the Ty. putrescentiae was the most suitable prey for mass rearing of N. bicaudus. The artificial diet could not support the N. bicaudus population and needs to be improved. [ABSTRACT FROM AUTHOR]

Population models can provide insights into how perturbations of demographic vital rates influence population growth rates (λ) and help prioritize efforts to achieve management goals. Although population models have been developed for numerous duck species, this tool has not been developed for ring‐necked ducks (Aythya collaris). Ring‐necked ducks are a late‐nesting species that may not be surveyed well by the May Waterfowl Survey, which is timed optimally for earlier nesting ducks like the mallard (Anas platyrhynchos). Information specific to ring‐necked ducks would help identify important influences on the rate of population growth and the direction of population change. We used data from our own research during 2008–2012, long‐term (1975–2016) survey data from northcentral Minnesota, USA, vital rate estimates from the literature, and long‐term (1987–2016) banding data to develop a population model for ring‐necked ducks. We estimated annual survival and recovery rates of after‐hatching‐year and hatching‐year female ring‐necked ducks in Minnesota. Survey results and our matrix models indicated that ring‐necked ducks are declining in the forested portion of Minnesota. Thus, we examined a boom‐or‐bust simulation scenario that might maintain a population through periodic occurrence of exceptional reproductive years in conjunction with high hatching‐year survival. Our results indicated that long‐term persistence is only expected in this population if reproductive output doubled at the same time that hatching‐year survival was at its highest value, or if the population is maintained through immigration. Sensitivity analysis indicated that unit changes in 30‐day brood survival will produce the most change in λ in the parameter space observed, although elasticity analysis indicated that proportional changes in annual survival of adult females will produce the largest proportional changes in λ. Management to improve brood survival to increase λ might include improving the habitat quality of brood‐rearing lakes, especially those with more open water and less nesting habitat than those used for nesting. Our findings might also help explain disparities between annual breeding waterfowl surveys, which indicate stable or increasing populations, and hunter experiences in the fall. In Minnesota, hunter experiences have not matched expectations based on historical fall numbers and this could occur if regional production declined and fewer young birds were available for harvest. Our findings highlight the need for further study to inform management in this rapidly changing region. © 2019 The Wildlife Society. Our demographic model suggests that the ring‐necked duck population in the forested portion of Minnesota is declining and that immigration may be sustaining the population. Given the inadequate coverage of forest‐nesting waterfowl in the May Waterfowl Survey, and the imprecision of estimates from banding data due to the difficulty obtaining large samples annually during pre‐season banding, we recommend further study in this region to ensure that the population is managed for long‐term sustainability in this rapidly changing region. [ABSTRACT FROM AUTHOR]

Myzus persicae (Sulzer) is an important agricultural pest worldwide that imparts substantial damage to various horticultural and agricultural crops. Broflanilide is a newly developed insecticide that exhibits high activity against crop pests such as M. persicae. Nevertheless, the effects of sublethal levels of broflanilide on M. persicae fitness and population growth remain unclear. We assessed the sublethal and transgenerational effects of broflanilide on M. persicae performance using an age-stage, two-sex life table. Our results reveal that broflanilide is highly toxic to M. persicae with a 72-h LC 50 of 2.541 mg/L. The LC 25 of broflanilide significantly reduced the longevity and fecundity of the F 0 and F 1 generations, and the LC 10 and LC 25 of broflanilide significantly prolonged the developmental period of the third instar nymph in the F 1 generation. The net reproductive rate (R 0), intrinsic rate of increase (r), and finite rate of increase (λ) were significantly lower in the LC 25 -treated aphids. LC 25 broflanilide treatment significantly downregulated the reproduction-related genes ERR and Vg and significantly upregulated JHEH expression in the F 0 generation. LC 25 and LC 10 broflanilide treatments significantly upregulated the detoxification-related genes CarE and CYP6CY3 , respectively, which may be related to broflanilide resistance in M. persicae. These results showed that broflanilide LC 25 exhibited a significant inhibitory effect on M. persicae populations, which can persist in the F 1 generation. Our study facilitates the understanding of the sublethal effect of broflanilide on aphid performance and helps develop methods and programs for controlling M. persicae using low broflanilide doses. • Broflanilide exhibits relatively high toxicity to M. persicae. • The LC 25 concentration of broflanilide significantly inhibited the growth of M. persicae in the F 0 and F 1 generations. • The dosage of broflanilide should be considered when it is used for controlling M. persicae. [ABSTRACT FROM AUTHOR]