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The efficiency of pistachio nuts was investigated on the multiplication of Ectomyelois ceratoniae (Zeller) (Lep: Pyralidae) by rearing a cohort of 61 eggs individually at 26 ± 1 ℃, 60 ± 10% RH, and 16:8 h L:D. The age-stage two-sex life table theory and bootstrapping were used to analyze the data. The survival probability from a newly born egg to larva, pupa, and male and female adults was 0.77, 0.52, and 0.26 and 0.24, respectively. The total immature duration of males (45.33 d) was significantly shorter than that of females (49.47 d). The mean female fecundity was 98.08 eggs/fertile female (n = 12) and 78.46 eggs/all females (n = 15), respectively. The life expectancy of a newborn E. ceratoniae was 34.83 d, and the reproductive value was 79.63 at age 49 d of the female. Female moths had slightly longer longevity (7.82 d) compared with males (7.58 d). The population parameters R0, r, and λ were 19.29 offspring, 0.0548 d−1, and 1.0563 d−1, respectively. When eggs are harvested and the discard age is 62 d, the maximum harvest rate is 0.9481. Therefore, for a daily harvest of 10,000 eggs, the daily recruits of 547 eggs, 421 larvae, 287 pupae, 134 females, and 143 males are required in a stable stage structure rearing system. Each larva damaged and fed upon 2 gr. of raw pistachio to complete its development. Consequently, about 842 gr. pistachio nuts must be provided daily to meet the larval feeding demand, which imposes a cost of about $10 (local retail price) to the rearing system as nutritional provision. [ABSTRACT FROM AUTHOR]

If a structured discrete-time population model $ x_n = F(x_{n-1}) $ x n = F (x n − 1) , $ n \in {\mathbb {N}} $ n ∈ N , takes account of two-sexes, the year-to-year turnover operator F often has a first-order approximation B that is homogeneous and order-preserving rather than linear and positive. Still, one can define the spectral radius $ {\mathcal {T}} = \mathbf{r}(B) $ T = r (B) , the basic turnover number, which plays the role of a threshold parameter between extinction and persistence. If $ {\mathcal {T}} \lt 1 $ T < 1 , the extinction state is locally stable, and if $ {\mathcal {T}} \gt 1 $ T > 1 the population shows various degrees of persistence that depend on the irreducibility properties of the dispersal kernels. This threshold property raises interest in the continuous dependence of the basic turnover number on the parameters in the population model. In this paper, we concentrate on the continuous dependence of $ {\mathcal {T}}=\mathbf{r}(B) $ T = r (B) on mating functions. [ABSTRACT FROM AUTHOR]

This study seeks to characterise the effects of migration on the population development of Hong Kong where there has been rapid population transition due to extremely low fertility and uncertainties in migration flows. We explore actual historical trends during the period 2011–2021, and how these trends could shape the future demographic distribution if they persist. Using population census data, we estimate the net migration numbers in Hong Kong during the period 2011–2021, and develop population projections from 2026 to 2056 based on three alternative migration scenarios: (1) no net migration, (2) constant at the 2016–2021 level (negative growth), and (3) constant at the 2011–2016 level (positive growth but stable). Projected overall dependency ratios are also estimated under the three migration scenarios, as well as two retirement age scenarios: retiring at 65 years and 70 years. Our findings demonstrate that immigration would become an important and positive factor to slow down the process of population ageing to achieve a more sustainable development. The extension of the retirement age from 65 years to 70 years will certainly help to mitigate the ageing pressure in Hong Kong. We also provide implications of these projections for other Asian societies in similar situations. [ABSTRACT FROM AUTHOR]

Ostrinia furnacalis (Guenée) (Lepidoptera: Crambidae), a highly destructive pest in Asia, poses a significant threat to maize production by causing substantial yield losses. However, there is a lack of information regarding the impact of temperature variations on its population dynamics and the age-stage and two-sex life table. This study aimed to investigate the impact of 4 temperatures (20 °C, 24 °C, 28 °C, 32 °C) on the development, reproduction, and survival of O. furnacalis under controlled laboratory conditions. Our results revealed that O. furnacalis successfully developed, survived, and laid eggs across the tested temperatures (20–32 °C). The shortest developmental duration for all immature stages was observed at 32 °C. Conversely, increasing temperatures led to decreased longevity. Among the temperatures tested, 28 °C proved to be optimal for O. furnacalis , exhibiting the highest intrinsic rate of increase, finite rate of increase, and net reproductive rate. Our findings indicate that O. furnacalis thrives within a wide temperature range of 20–32 °C, with 28 °C being the most favorable for reproduction. These insights are crucial for predicting population dynamics under diverse climatic conditions and developing effective control strategies against O. furnacalis. This study enhances our understanding of O. furnacalis ' life-history traits and provides valuable information for targeted pest management approaches. [ABSTRACT FROM AUTHOR]

Dynamic microsimulations are tools to stochastically project (synthetic) microdata into the future. In spatial microsimulations, regional discrepancies are of particular interest and must be considered accordingly. In practice, the probabilities for state changes are unknown and must be estimated, usually from survey data. However, estimating such models on the regional level is often not feasible due to limited sample size and lack of geographic information. Simply applying the model estimated at the national level to all geographies leads to biased state transitions due to regional differences in level and distribution. In this paper, we introduce a model-based alignment method to adapt predicted probabilities obtained from a nationally estimated model to subregions by integrating known marginal distributions to re-introduce regional heterogeneity and create more realistic trajectories, particularly in small areas. We show that the model-adjusted transition probabilities can capture region-specific patterns and lead to improved projections. Our findings are useful to researchers who want to harmonise model outputs with external information, in particular for the field of microsimulation. [ABSTRACT FROM AUTHOR]

The life table data of papaya mealybug, Paracoccus marginatus Williams and Granara de Willink (Hemiptera: Pseudococcidae), on the jatropha, Jatropha integerrima (Euphorbiaceae), were collected using individually- and group-rearing and analyzed by using the age-stage, two-sex life table. Because the male individuals have six stages while the female individuals have only five stages, a new method was developed for a correct description of life stages and life table analysis. In general, the developmental durations of individually-reared insects were significantly longer than those of group-reared insects. Although the mean fecundity (F = 167.84 eggs/female) and the net reproductive rate (R0 = 62.10 offspring) of the individually-reared cohort were significantly higher than those of group-reared cohort (F = 66.5 eggs/female and R0 = 18.62 offspring), there were no significant differences in the population growth rates, i.e., intrinsic rate of increase r and finite rate of increase λ. Because the age variable x is an exponent in the Euler-Lotka equation, the first reproductive age and total preoviposition period are important factors in the determining the value of population growth rates. The life table data were used to simulate the population growth and timing of the control. Our results demonstrated that for grouplived insects like papaya mealybug, life table data collected using group-reared cohort is a better option for simulating pest population growth and management than data from individually-reared cohort. [ABSTRACT FROM AUTHOR]

Although Trichogramma principium (Sugonjaev & Sorokina) (Hymenoptera: Trichogrammatidae) is an effective natural enemy in agricultural ecosystems, its tri-trophic interactions should be investigated in more detail. In the present study, life table parameters of the parasitoid wasp and its population projection were investigated under controlled conditions (25 ± 1 °C, 60 ± 5% RH, and 16:8 h L:D) on Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae). The herbivore was reared using three different cultivars, including Early Urbana, Super Strain-B, and Primo Early, as well as being treated with four nitrogen levels (0, 2100, 3000, and 3900 ppm). Data analysis was performed based on an age-stage two-sex life table by linking the life table parameters and population projection. Results indicated a significant increase in net reproductive rate (R0) and intrinsic rate (r). Therefore, the fertilized treatments were relatively favorable hosts for the herbivore and consequently for the parasitoid wasps than unfertilized treatments. Population projection results also indicated differences in the stage population growth rate, age-staged population fluctuations and the parasitism capacity of the parasitoid. These findings indicated that linking life table and population projection is an appropriate method for clarifying the precise timing and the successful release of natural enemies. [ABSTRACT FROM AUTHOR]

Abstract Brazil’s population has continually changed over time. However, the effects of each demographic component on official population projections are still unclear. In this research, we replicate the Population Projections Revision 2018 of the Brazilian Institute of Geography and Statistics using a projection matrix model and the cohort-component method by sex, age and geographic regions. Thereafter, we established four alternative scenarios to decompose the official benchmark scenario into four demographic effects (fertility, age structure, mortality, and migration) and one residual effect. The results reveal that fertility and age structure effects have been the main drivers of the population dynamics between 2010 and 2060. On the one hand, the negative effect of fertility below replacement level has been mostly offset by the still positive effect of the age structure, even across regions in the country. On the other hand, age structure effect has been decreasing over time. By 2048, the effects of age structure, mortality and migration will no longer counterbalance fertility effects, resulting in a population decline.

Since metabolism, survival, and reproduction in hexapods are closely related to temperatures; changes in the mean and variance of temperature are major aspects of global climate change. In the typical context of biological control, understanding how predator–prey systems are impacted under thermal conditions can make pest control more effective and resilient. With this view, this study investigated temperature-mediated development and predation parameters of the predator Harmonia axyridis against the potential prey Spodoptera litura. The age-stage, two-sex life table of the predator was constructed at four temperatures (i.e. 15, 20, 25, and 30°C) by feeding on the first instar larvae of S. litura. Our results showed that the mean generation time (T) decreased but the intrinsic rate of increase (r) and the finite rate of increase (λ) increased with increased temperature. The mean duration of the total preadult stage decreased with higher temperatures. The T and r were 70.47 d and 0.0769 d−1 at 15°C; 58.41 d and 0.0958 d−1 at 20°C; 38.71 d and 0.1526 d−1 at 25°C; and 29.59 d and 0.1822 d−1 at 30°C, respectively. The highest net reproductive rate (R 0) and fecundity were obtained at 25°C. The highest λ (1.1998 d−1) and lowest T (29.59 d) were obtained at 30°C, whereas the maximum net predation rate (C 0) was at 25°C. Total population and predation rates projections were the highest at 30°C. Based on these findings, we anticipate that biological control strategies for this predator release against S. litura should be attuned to warming scenarios to achieve better biocontrol functions. [ABSTRACT FROM AUTHOR]

Heat waves, such as the one that struck European Russia in 2010, are among the major dangers of climate change. The population shift to large cities and southern regions observed in Russia, together with warming, increases the risks from heat waves. In this paper, we provide estimates of current and future population exposure to heat waves in Russian regions under the projection scenarios introduced by IPCC for the mid-21 century. We aim at identifying regions most at risk and in need of adaptation strategies and at assessing the contribution of climate change and population dynamics to future changes in population exposure. We use both absolute and relative measures to detect extreme summer daily temperatures and the high-resolution population data for the current period and 2050. Our results show an increase in the aggregate exposure from 4.76 billion person-days in the current period to 5.86 and 7.52 billion person-days under the soft and hard scenarios, respectively, notably in the areas where absolute maximum summer temperatures exceed 30 °C and 35 °C. Against the overall population decline, the increase in exposure is mainly driven by the climatic factor: by the widespread increase in the number of relatively very warm days, up to most of the season in the coastal areas of the Black and Caspian Seas and in the Caucuses, and by the geographical expansion of the zone of absolute high temperatures above 30 °C into the densely populated regions of Russia’s Main Settlement Belt in Middle Russia, the southern Urals and Siberia. The projected more extreme climate put at risk the regions with large urban agglomerations and a relatively high population density making heat waves to increasingly become a metropolis-related risk, and the few regions that are projected to grow in population size, both through migration inflows, such as Krasnodar Krai, Moscow region, and Tyumen region, and through natural increase, such as the republics of the Caucasus. [ABSTRACT FROM AUTHOR]

Household water demand has increased dramatically in Kuwait over the last few decades, due to rapid population growth and changing lifestyles. Avoiding a water deficit through a supply‐side approach has been the default strategy in Kuwait, yet this approach is unsustainable, associated with declining groundwater levels, and reliance on desalination that results in major carbon emission and environmental impact and that takes a large and growing share of oil revenues. In this study, we forecast household water demand in Kuwait to 2050 under a Business‐As‐Usual (BAU) scenario and evaluate the economic and environmental impacts. A spatial microsimulation, constrained by the national population projection of the Kuwait Institute of Scientific Research (KISR), was developed to overcome data limitations in forecasting household demand. Results show a 45% increase in water demand by 2050, to 664.1 million cubic metres (MCM), relative to the 2019 base year. Annual production costs increase from 1.39 billion USD in 2019 to 1.99 billion USD by 2050, whilst carbon emissions increase from 10.85 to 15.54 million tonnes/year. These results should alert policymakers to the potential impacts of the growing water demand and provide further support for water conservation action to reduce demand. [ABSTRACT FROM AUTHOR]

Simple Summary: The two-spotted spider mite Tetranychus urticae and its interactions with fungi, notably Beauveria bassiana, on common bean plants were the main subjects of this study. The mite's life cycle on untreated and endophyte-colonized plants was examined using the age-stage, two-sex life table hypothesis. The findings indicated that mites reared on untreated plants had shorter developmental stages and higher fecundity than those on colonized plants. Furthermore, mites on untreated plants displayed a higher intrinsic rate of increase and net reproductive rate. The study also revealed that fungal endophyte colonization negatively affected mite growth, adult lifespan, fecundity, reproductive rate, and the intrinsic rate of increase. The findings point to a possible application of entomopathogenic fungal endophytes in host plant resistance programs for future integrated pest control. Tetranychus urticae is a highly polyphagous and global pest. Spider mites primarily feed on the underside of leaves, resulting in decreased photosynthesis, nutritional loss, and the development of chlorotic patches. We investigated the life tables of the two-spotted spider mite T. urticae on fungal endophyte Beauveria bassiana colonized and untreated plants of the common Phaseolus vulgaris L., a bean plant. Based on the age-stage, two-sex life table theory, data were evaluated. The mites raised on untreated plants had protonymphs, deutonymphs, and total pre-adult stage durations that were considerably shorter (1.76, 2.14, and 9.77 d, respectively) than the mites raised on plants that had been colonized (2.02, 2.45, and 10.49 d, respectively). The fecundity (F) varied from 28.01 eggs per female of colonized plants to 57.67 eggs per female of endophyte-untreated plants. The net reproductive rate (R0) in the plants with and without endophytes was 19.26 and 42.53 brood, respectively. The untreated plants had an intrinsic rate of increase (rm) of 0.245 days as opposed to the colonized plants, which had an r of 0.196 days and a finite rate of increase (λ) (1.27 and 1.21, respectively). Population forecasts based on a two-sex, age-stage life table demonstrated the dynamism and variability of the stage structure. Furthermore, the colonization of B. bassiana had a negative impact on the growth and development of T. urticae. It lowered the adult mite life span, female fecundity, net reproduction rate, and intrinsic growth rate. We propose that future research should better use entomopathogenic fungal endophytes to understand host plant resistance strategies in integrated pest management. [ABSTRACT FROM AUTHOR]

The demography and population fitness of fall armyworm, Spodoptera frugiperda was studied by comparing ambient (31 °C + 415 ppm) with elevated (33 °C + 460 ppm and 35 °C + 520 ppm) environmental conditions. The experiments with temperature and CO2 levels were conducted by using Soil Plant Atmosphere Research (SPAR) chamber. The life history data of S. frugiperda was analyzed by age-stage, two-sex life table. Results revealed that developmental time and age-stage-specific survival rate (sxj) of S. frugiperda at age (x) and stage (j) reduced with the increase in temperature and CO2 levels. The fecundity rate and age-stage-specific reproductive rate (vxj) at age x and stage j were recorded highest at 33 °C + 460 ppm but it was significantly reduced at 35 °C + 520 ppm. S. frugiperda reared under an elevated level of 33 °C + 460 ppm showed the highest net reproductive rate (R0), intrinsic (rm), and finite rate of increase (λ) when compared to ambient. However, these fitness traits decreased at the elevated level of 35 °C + 520 ppm. These results suggest that the fitness traits of S. frugiperda were altered concerning the future scenario of global climate change under increasing temperature and CO2 levels. [ABSTRACT FROM AUTHOR]

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BACKGROUND: Because of the considerable damage caused by tomato leafminer in tomato crops, the use of integrated methods is recommended. In this study, the effect of three different elicitors, methyl jasmonate, salicylic acid and ascorbic acid, on the life table parameters of Tuta absoluta was evaluated. A paired bootstrap test and different bootstrap percentiles were used to compare projected population sizes on specific dates. Survival probabilities were calculated by innovatively linking life tables and multinomial theorem. RESULTS: Preadult duration and mortality significantly increased, and the net reproductive rate (R0), intrinsic rate of increase (r), and finite rate of increase (λ) significantly decreased in all elicitor treatments. The lowest fecundity (F = 71.89 eggs/female) was observed in the salicylic acid treatment, with an R0 value of 13.48 offspring/individual, r of 0.0932 d−1, and λ of 1.0977 d−1. The population projection revealed the stage structure of T. absoluta during population growth, which was significantly reduced by the elicitor treatments. The survival probability of bootstrap samples was significantly lowered, whereas the extinction probabilities increased in elicitor treatments compared with control when the survival criterion was set to two fertile pairs. CONCLUSION: Our results demonstrated that the application of elicitors could reduce the risk of T. absoluta damage. Furthermore, population projection based on life tables is applicable to obtain the frequency distribution of the population size at different times. Combined application of life tables and multinomial theorem can be used to calculate the risk of pest emergence. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The size of the world’s population has profound implications for demand for food, energy and resources, land use change and greenhouse gas emissions. This study examines why most population projections have underestimated world population growth, and the implications for actions required to achieve sustainable societies. The main determinant of future population is family size choices. Population projections by different research groups embed different assumptions about drivers of fertility decline. The common assumptions that fertility decline is driven by economic betterment, urbanisation or education levels are not well supported in historical evidence. In contrast, voluntary family planning provision and promotion achieved rapid fertility decline, even in poor, rural and illiterate communities. Projections based on education and income as drivers of fertility decline ignore the reverse causation, that lowering fertility through family planning interventions enabled economic advancement and improved women’s education access. In recent decades, support for family planning has waned, and global fertility decline has decelerated as a result. Projections calibrated across the decades of strong family planning support have not acknowledged this change and are consequently underestimating global population growth. Scenarios used to model sustainable futures have used overly optimistic population projections while inferring these outcomes will happen without targeted measures to bring them about. Unless political will is rapidly restored for voluntary family planning programs, the global population will almost certainly exceed 10 billion, rendering sustainable food security and a safe climate unachievable.

This study presents an analysis of population trends in rural Norway, with a specific focus on the potential implications for rural populations in a long-term perspective. We highlight the significant outward migration of young people from rural areas, which has led to a demographic shift happening at a faster pace and on a larger scale in rural areas compared to central areas. Using North-Varanger, the most north-eastern part of the country, as an example, the article shows that the region has experienced net outward migration for the past 50 years, and if current trends persist, the population in the region could decrease by up to 80 percent by 2100. North-Varanger is an area of strategic importance to Norway. It is also an area of vital importance for the Sami people. This study shows that there is a risk that the population in one of the most strategically important regions will see a dramatic reduction. The only way to reverse this trend is to change the migration patterns and encourage more young families to settle in North-Varanger. This stresses the urgent need for policymakers to re-evaluate current public measures aimed at attracting migrants to rural areas in order to make the measures more effective and to ensure sustainable settlement in the region.

Dynamic microsimulations are tools to stochastically project (synthetic) microdata into the future. In spatial microsimulations, regional discrepancies are of particular interest and must be considered accordingly. In practice, the probabilities for state changes are unknown and must be estimated, usually from survey data. However, estimating such models on the regional level is often not feasible due to limited sample size and lack of geographic information. Simply applying the model estimated at the national level to all geographies leads to biased state transitions due to regional differences in level and distribution. In this paper, we introduce a model-based alignment method to adapt predicted probabilities obtained from a nationally estimated model to subregions by integrating known marginal distributions to re-introduce regional heterogeneity and create more realistic trajectories, particularly in small areas. We show that the model-adjusted transition probabilities can capture region-specific patterns and lead to improved projections. Our findings are useful to researchers who want to harmonise model outputs with external information, in particular for the field of microsimulation.

The size of the world's population has profound implications for demand for food, energy and resources, land use change and greenhouse gas emissions. This study examines why most population projections have underestimated world population growth, and the implications for actions required to achieve sustainable societies. The main determinant of future population is family size choices. Population projections by different research groups embed different assumptions about drivers of fertility decline. The common assumptions that fertility decline is driven by economic betterment, urbanisation or education levels are not well supported in historical evidence. In contrast, voluntary family planning provision and promotion achieved rapid fertility decline, even in poor, rural and illiterate communities. Projections based on education and income as drivers of fertility decline ignore the reverse causation, that lowering fertility through family planning interventions enabled economic advancement and improved women's education access. In recent decades, support for family planning has waned, and global fertility decline has decelerated as a result. Projections calibrated across the decades of strong family planning support have not acknowledged this change and are consequently underestimating global population growth. Scenarios used to model sustainable futures have used overly optimistic population projections while inferring these outcomes will happen without targeted measures to bring them about. Unless political will is rapidly restored for voluntary family planning programs, the global population will almost certainly exceed 10 billion, rendering sustainable food security and a safe climate unachievable. [ABSTRACT FROM AUTHOR]

This study presents the population dynamics by ethnicity in the lands of Crișana Region, Romania, based on a population forecast for the year 2030. The aim of the study is to provide short term population dynamics information by comparison between the six lands and area of the region. Crisana is a heterogeneous area from ethnic point of view and migration has been intense in the past three decades, but some ethnicities have been more affected by this phenomenon than others, therefore this forecast is made by ethnicity and the results show different trends. The population of each Land and area is characterized by the studied ethnicities, but the numbers differ considerably. Also the lands and areas show different trends regarding the ethnic populations.The method used for population forecast is a quantitative method based on statistical data obtained from successive censuses. The reference years taken into study are 1900, 1030, 1992, 2002 and 2011. Despite the fact that by 2011 the trend was decreasing, because from 1900 to 1992, the number of population increased, the trend for 2030 is also of increase for most ethnicities.

Political decision-making related to future challenges, for example in the fields of medical care, the housing market or education highly depend on valid estimates of the future population size and structure. However, such developments are usually heterogeneous throughout a country making subnational projections necessary. It is well-known that these regional differences are highly influenced by both internal and external migration processes. In this paper, we investigate the consequences of different migration assumptions on regional development in Germany using a spatial dynamic microsimulation. We find that migration assumptions have a strong direct influence on the future population and composition at the regional level and, therefore, require special attention. Depending on the scenario selected, very different socio-demographic trends may emerge in specific districts or even district types. We also demonstrate that migration assumptions affect non-demographic indicators such as the participation rate, albeit to a lesser extent. The findings are relevant to understanding the sensitivity of population projections to migration assumptions both on the national and regional level. This also paves the way to analyze how potential political interventions behave under those assumed future migration processes. [ABSTRACT FROM AUTHOR]

The effects of three different CO2 concentrations (400, 600, and 1000 ppm) on the population parameters and growth of the green peach aphid, Myzus persicae, were examined. Raw life history data from M. persicae were analyzed using an age‐stage, two‐sex life table to take into account the viable development rate among individuals. The population projections of M. persicae indicate the stage structure and variability of the population growth under different CO2 concentrations based on an age‐stage, two‐sex life table analysis. Significantly longer oviposition duration and higher fecundity were observed under elevated CO2 (600 and 1000 ppm) than those under ambient CO2 (400 ppm). Furthermore, the M. persicae population reared under elevated CO2 concentrations showed higher intrinsic and finite rates of population increase than under ambient CO2 concentrations. These results indicate that the population parameters and growth of M. persicae were positively influenced in the fecundity by elevated CO2 concentrations relative to the ambient CO2. These findings indicate that it is basically remained to understand the direct effects of CO2 elevation on the host plants, and the interaction between the host plants and M. persicae in the same CO2 concentration for establishing more realistic population growth model systems for M. persicae in the aerial environment rising CO2 concentration level. [ABSTRACT FROM AUTHOR]

Tetranychus urticae is a highly polyphagous and global pest. Spider mites primarily feed on the underside of leaves, resulting in decreased photosynthesis, nutritional loss, and the development of chlorotic patches. We investigated the life tables of the two-spotted spider mite T. urticae on fungal endophyte Beauveria bassiana colonized and untreated plants of the common Phaseolus vulgaris L., a bean plant. Based on the age-stage, two-sex life table theory, data were evaluated. The mites raised on untreated plants had protonymphs, deutonymphs, and total pre-adult stage durations that were considerably shorter (1.76, 2.14, and 9.77 d, respectively) than the mites raised on plants that had been colonized (2.02, 2.45, and 10.49 d, respectively). The fecundity (F) varied from 28.01 eggs per female of colonized plants to 57.67 eggs per female of endophyte-untreated plants. The net reproductive rate (R0) in the plants with and without endophytes was 19.26 and 42.53 brood, respectively. The untreated plants had an intrinsic rate of increase (rm) of 0.245 days as opposed to the colonized plants, which had an r of 0.196 days and a finite rate of increase (λ) (1.27 and 1.21, respectively). Population forecasts based on a two-sex, age-stage life table demonstrated the dynamism and variability of the stage structure. Furthermore, the colonization of B. bassiana had a negative impact on the growth and development of T. urticae. It lowered the adult mite life span, female fecundity, net reproduction rate, and intrinsic growth rate. We propose that future research should better use entomopathogenic fungal endophytes to understand host plant resistance strategies in integrated pest management.

This study presents the population dynamics by ethnicity in the lands of Crişana Region, Romania, based on a population forecast for the year 2030. The aim of the study is to provide short term population dynamics information by comparison between the six lands and area of the region. Crisana is a heterogeneous area from ethnic point of view and migration has been intense in the past three decades, but some ethnicities have been more affected by this phenomenon than others, therefore this forecast is made by ethnicity and the results show different trends. The population of each Land and area is characterized by the studied ethnicities, but the numbers differ considerably. Also the lands and areas show different trends regarding the ethnic populations. The method used for population forecast is a quantitative method based on statistical data obtained from successive censuses. The reference years taken into study are 1900, 1030, 1992, 2002 and 2011. Despite the fact that by 2011 the trend was decreasing, because from 1900 to 1992, the number of population increased, the trend for 2030 is also of increase for most ethnicities. [ABSTRACT FROM AUTHOR]

Rice is the staple food and its cultivation requires a specific land condition. The population growth, urbanization, and plantation expansion together with socio-economic development are the driving factors of the riceland decline in Deli Serdang Regency of North Sumatera, Indonesia. As a consequence, likely availability and sustainability of rice production are threatened. Hence, it is important to understand how the future landuse and population change will affect the riceland area and production. In the lack of spatially simulated information for the future which could be useful in planning the riceland areas, the study objectives were to project the landuse change by 2040 under three scenarios, Business as Usual (BAU), Potential Riceland Protection (PRP) and Conservation Oriented (CO), and to investigate the impact of consumption demand on the sustainability of rice production. Landsat satellite data of 2009 and 2018, several spatial GIS data, and survey data were analyzed in ArcGIS, Dyna-CLUE, and SPSS software to generate the landuse classification and to simulate the future landuses; while the population projection by 2040 was derived from a Geometric Model. The results showed that forest and riceland areas will decrease with the continuous increase of plantation and urban areas under BAU scenario, but could be protected and increased under PRP scenario. The sustainability of rice production depends not only on the total riceland area, but also the productivity, the population growth, the consumption rate, and the policy. The simulated results of three scenarios serve as an important input to planning for protecting the riceland areas and thus sustained rice production in Deli Serdang Regency. [ABSTRACT FROM AUTHOR]

[Display omitted] • Temperature affects the development and survival of Perina nuda. • The life table parameters indicate that the optimum temperatures for rearing Perina nuda are between 24 °C and 28 °C. • The life table parameters were used to simulate the change trend of the population of P. nuda in 120 d at different temperatures. Perina nuda Fabricius (Lepidoptera: Lymantridae) has emerged as a major pest of Ficus spp. Linné (Rosales: Moraceae), exhibiting widespread distribution across southern China. The present study was designed to assess the impact of temperature on the development and lifetime fecundity of P. nuda. We gathered life-history data of P. nuda under four different temperatures (20 °C, 24 °C, 28 °C, and 32 °C) to analyze through the age-stage, two-sex life table methodology. Subsequently, projected population dynamics were made using these data. Results show that a generation can be completed at experimental temperature; the longest mean longevity (72.012 d) was recorded at 20 °C, while the shortest one was 29.126 d at 32 °C. The highest fecundity (219.5 eggs per female), preadult survival rate (90.6 %), and proportion of females (0.494) were observed at 24 ℃. At 20 °C, the intrinsic rate of increase (r) and the finite rate of increase (λ) were found to be much lower than at other temperatures, with 0.0575 and 1.0591 1/d, respectively. Compared to other temperatures, the net reproductive rate (R 0) at 24 ℃ (108.59) was notably higher than other temperatures. The developmental threshold temperatures and effective accumulated temperatures for egg, larva, pupa, and the entire generation were 10.7 °C (128.02 degree-days), 11.53 °C (362.59 degree-days), 11.86 °C (110.4 degree-days), and 10.85 °C (780.98 degree-days), respectively. A higher population growth rate and a larger population number was observed at 24℃, 28℃ and 32 ℃. Predicted generations varied across Guangdong, ranging from 4.68 in Nanxiong to 6.42 in Leizhou. These findings will help understanding P. nuda biology as influenced by temperature and may be used to predict the distribution and infestation risk under climate warming for this pest of banyan trees. [ABSTRACT FROM AUTHOR]

Across the developed world, declines in mortality rates associated with the improvement in health conditions and increase in living standards led to declines in fertility rates. The demographic transition process has been experienced as the fertility and mortality rates declined from very high levels to very low levels. Population policies implemented by public authorities to address births have also been effective in the demographic change process. Although the demographic transition is a global process, the development levels and socioeconomic characteristics of the countries have caused the demographic change process to be experienced at different times on a country basis. Significant decreases in fertility and mortality rates since the middle of the twentieth century in Turkey resulted in a rapid demographic transition. This demographic change, which continues as a process, has been effective in changing the structural characteristics of the country's population. In this study, the effects of the demographic transition in Turkey on the total population structure and the future of the country's population have been examined based on the population projections of the United Nations (UN). The study based on the quantitative data obtained from the population surveys of the State Institute of Statistics, Turkish Statistical Institute (TSI) and the UN.The study reveals the necessity of measures to eliminate the negative conditions that prevent parents from having children in order to keep the fertility rate at the level of the reproduction rate. [ABSTRACT FROM AUTHOR]

Accurate estimates of subnational populations are important for policy formulation and monitoring population health indicators. For example, estimates of the number of women of reproductive age are important to understand the population at risk of maternal mortality and unmet need for contraception. However, in many low-income countries, data on population counts and components of population change are limited, and so subnational levels and trends are unclear. We present a Bayesian constrained cohort component model for the estimation and projection of subnational populations. The model builds on a cohort component projection framework, incorporates census data and estimates from the United Nation’s World Population Prospects, and uses characteristic mortality schedules to obtain estimates of population counts and the components of population change, including internal migration. The data required as inputs to the model are minimal and available across a wide range of countries, including most low-income countries. The model is applied to estimate and project populations by county in Kenya for 1979–2019 and is validated against the 2019 Kenyan census. [ABSTRACT FROM AUTHOR]

Temperature can influence the developmental rate and reproductive potential of herbivorous insects and mites. Amblyseius swirskii Athias-Henriot is an effective phytoseiid predator with a significant ability to repress pest populations. To better understand the effect of temperature on the performance of A. swirskii, we studied temperature-dependent population growth and reproductive potential of the predatory mite under six constant temperatures (20, 22, 25, 27, 30, and 32°C), providing 75 ± 5% RH and a photoperiod of 16 L: 8 D h. The average fecundity was 12.85, 18.24, 22.2, 27.24, 28.6, and 52.57 eggs/female at 20–32°C, respectively. The highest gross reproductive rate (GRR = 26.08 eggs/individual), net reproductive rate (R0 = 22.51 eggs/individual), and intrinsic rate of increase (r = 0.174 day–1) were recorded at 27°C. The finite rate of increase (λ) and mean generation time (T) of A. swirskii were profoundly affected by temperature and varied from 1.101 to 1.190 day–1 and 10.85 to 19.09 days, respectively. Data obtained during this study indicated that 27°C is the best temperature for rearing this predatory mite. This study improves our findings of the temperature range to optimize the mass rearing of A. swirskii as an effective predatory mite. [ABSTRACT FROM AUTHOR]

Rice is the staple food and its cultivation requires a specific land condition. The population growth, urbanization, and plantation expansion together with socio-economic development are the driving factors of the riceland decline in Deli Serdang Regency of North Sumatera, Indonesia. As a consequence, likely availability and sustainability of rice production are threatened. Hence, it is important to understand how the future landuse and population change will affect the riceland area and production. In the lack of spatially simulated information for the future which could be useful in planning the riceland areas, the study objectives were to project the landuse change by 2040 under three scenarios, Business as Usual (BAU), Potential Riceland Protection (PRP) and Conservation Oriented (CO), and to investigate the impact of consumption demand on the sustainability of rice production. Landsat satellite data of 2009 and 2018, several spatial GIS data, and survey data were analyzed in ArcGIS, Dyna-CLUE, and SPSS software to generate the landuse classification and to simulate the future landuses; while the population projection by 2040 was derived from a Geometric Model. The results showed that forest and riceland areas will decrease with the continuous increase of plantation and urban areas under BAU scenario, but could be protected and increased under PRP scenario. The sustainability of rice production depends not only on the total riceland area, but also the productivity, the population growth, the consumption rate, and the policy. The simulated results of three scenarios serve as an important input to planning for protecting the riceland areas and thus sustained rice production in Deli Serdang Regency.

We evaluated the sublethal (LC25) effects of the three native strains of two important entomopathogenic fungi (EPFs) species (Metarhizium anisopliae AB, M. anisopliae Iran 245, and Beauveria bassiana 106) on the cabbage aphid, Brevicoryne brassicae L. (Hemiptera: Aphididae) which is among the most destructive pests of cole crops. Studies were carried out in controlled conditions providing 25 ± 2 °C, 60% ± 5% RH and a photoperiod of 16:8 h (L:D). The age-stage, two-sex life table method was used for data analysis. The results indicated that EPF treatments affected the population growth rate of the aphids by causing prolongation of the development time, decrease in survival rate, shortening of adult longevity, and decrease in reproduction. The intrinsic rate of increase (r) and the finite rate of increase (λ) reflecting combined effects of all life history parameters were the highest in the control group and the lowest in M. anisopliae AB treatment. Similarly, the mean generation time was the shortest in the control treatment and the longest in M. anisopliae AB group. The overall results demonstrated that EPFs tested in this study could be considered an alternative option in the IPM programs against cabbage aphid, and M. anisopliae strain AB is the most promising EPF for further evaluation. [ABSTRACT FROM AUTHOR]

The current panorama that concerns the urbanization of the cities, takes place through the city-to-city migration in addition to the vegetative growth. For this, the present study seeks to carry out a population projection until the year 2040 for the municipality of Santa Isabel do Pará. For this study, IBGE data were used added to the use of statistical tools to obtain more adequate, reliable and important results. for a territorial ordering through the public management of the municipality and private companies. In this study, among the estimated demographic models for population projections in the municipality of Santa Izabel do Pará, the most convenient method among those tested in this research was the Geometric, because it presents consistent results observing the populations of the 1991 to 2010 Demographic Censuses. Also, the one that best fit the census data (1991, 2000 and 2010), observing the R² coefficient, presented a positive result of 0.98, indicating that the two variables express a strong correlation. The conception of long-term hypotheses for demographic factors is of paramount importance in the development and execution of projections, as it indisputably contributes to the excellence and accuracy of the applied model. [ABSTRACT FROM AUTHOR]

Spodoptera frugiperda (JE Smith) is one of the most destructive pests, causing serious yield losses of corn on all continents except Europe. Low-lethal concentrations of insecticides may affect not only the survival rate but also the demographic parameters of a pest. To understand the effect of low-lethal concentrations of insecticides on S. frugiperda , the developmental parameters after low-lethal concentrations treatment by three different modes of action pesticides tetrachloroamide, spinetoram, and lufenuron were analyzed. For F0 generation, the pupal length and weight of FAW after insecticide treatment were significantly longer and heavier than that of control. For the F1 generation, the adult longevity and egg hatching rate after spinetoram and lufenuron treated was significantly shorter and lower than that of the control. While no significant effect was observed for the intrinsic rate of increase (r), finite rate of increase (λ), and mean generation time (T) of S. frugiperda , the net reproductive rate (R 0) significant decreased after the spinetoram and lufenuron treatment. Results showed tetrachloroamide, spinetoram, and lufenuron negatively affect larval survival rate, but spinetoram and lufenuron caused early maturity, and all three insecticide treatments increased egg reproduction. The results of this study suggest that low-lethal concentration exposure to insecticides negatively impacts the life table parameters of S. frugiperda , and those three insecticides from different modes of action cannot cause FAW resurgence and can be recommended as insecticides to control FAW. Those results will be helpful for researchers working on S. frugiperda management using chemical pesticides in an integrated pest management program. • The developmental parameters of Spodoptera frugiperda were affected by insecticide treatment. • Sublethal insecticide treatment caused early maturity and increased egg production. • Sublethal effects of the tested pesticides did not cause a resurgence in S. frugiperda. [ABSTRACT FROM AUTHOR]

Political decision-making related to future challenges, for example in the fields of medical care, the housing market or education highly depend on valid estimates of the future population size and structure. However, such developments are usually heterogeneous throughout a country making subnational projections necessary. It is well-known that these regional differences are highly influenced by both internal and external migration processes. In this paper, we investigate the consequences of different migration assumptions on regional development in Germany using a spatial dynamic microsimulation. We find that migration assumptions have a strong direct influence on the future population and composition at the regional level and, therefore, require special attention. Depending on the scenario selected, very different socio-demographic trends may emerge in specific districts or even district types. We also demonstrate that migration assumptions affect non-demographic indicators such as the participation rate, albeit to a lesser extent. The findings are relevant to understanding the sensitivity of population projections to migration assumptions both on the national and regional level. This also paves the way to analyze how potential political interventions behave under those assumed future migration processes.

Climate change negatively impacts agricultural production influencing the rural-to-urban migration options of the population. In this study, we investigate the effects of expected climate change on population distribution and outmigration from rural areas of the Northeast region of Brazil (NEB) over the coming decades under different socioeconomic and climate scenarios. Demographic projection models to 2060 were created based on assumptions of future fertility, mortality, migration, and educational transition. Results reveal that changes in rural population size and composition and rural outmigration may emerge depending on future climatic conditions, agricultural income, and education. The highly-educated population can adapt with changes in climate and avoid income loss while earnings of those with lower education are reduced. The latter's outmigration option is also limited because of lower qualifications. Policies should support economically vulnerable populations especially those dependent on agriculture. Also, policies must accommodate alternative climate change scenarios and their consequences on rural population displacement. • Population projections contribute to identifying the vulnerabilities of populations. • Population scenarios are useful to explore the global climate change challenges. • Climate change influences the rural-to-urban migration options of the population. • Changes in rural population size emerge depending on future climatic conditions. • Education is an important component in shaping future rural population distribution. [ABSTRACT FROM AUTHOR]

Simple Summary: Influenced by global climate, trade, and transportation factors, Bactrocera dorsalis (Hendel) has gradually spread from southern regions to Beijing, Hebei, and other northern areas in China. In order to evaluate the risk of damage of B. dorsalis to the dominant northern fruits, an age-stage two-sex life table was used to study the fitness of B. dorsalis for peaches and apples, with oranges as the control. Our results showed that the pest can cause continuous damage on northern fruit hosts, with the damage degree being basically the same on peaches as on the southern fruit of oranges. The B. dorsalis population on peaches increased by 12,112.1 times 90 days after oviposition, easily causing great damage. Additionally, the population increased by 4311 times on apples, which may also become a potentially new host of B. dorsalis in northern China, though with relatively lower fitness. This research lays a foundation for monitoring and the formulation of efficient control strategies for B. dorsalis. 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. [ABSTRACT FROM AUTHOR]

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]