Current biodiversity loss was generally considered to be caused by anthropogenic disturbance, but when anthropogenic activities began to impact biodiversity loss is still controversial. One hypothesis suggested it was from the industrial era, while others proposed that the anthropogenic disturbance had already resulted in biodiversity decline since the Early Holocene. To test these hypotheses, we focus on subtropical East Asia, which has witnessed a land use and anthropogenic history since the Early Holocene. We selected the unique vegetation of evergreen broadleaved forests (EBLFs), using a genomic approach to infer the demographic history of a dominant plant (Litsea elongata) of EBLFs, and to further detangle the impact of climate change and/or anthropogenic disturbance on effective population size fluctuation. Nine well-defined geographical clades were identified within extant populations of L. elongata. The estimated historical population sizes of these clades all contracted, indica...

The world's population first reached one billion people in 1805, and reached eight billion in 2022, and will peak at almost 10.2 billion by the end of the century. Although it took thousands of years to reach one billion people, it did so at the beginning of a phenomenon known as the demographic transition; from this point onwards, population growth has skyrocketed, and since the 1960s the population has increased by one billion people every 12 to 15 years. The demographic transition sees a sharp drop in mortality due to factors such as vaccination, sanitation, and improved food supply; the population boom that follows is due to increased survival rates among children and higher life expectancy among the general population; and fertility then drops in response to this population growth. Regional differences The demographic transition is a global phenomenon, but it has taken place at different times across the world. The industrialized countries of Europe and North America were the first to go through this process, followed by some states in the Western Pacific. Latin America's population then began growing at the turn of the 20th century, but the most significant period of global population growth occurred as Asia progressed in the late-1900s. As of the early 21st century, almost two-thirds of the world's population lives in Asia, although this is set to change significantly in the coming decades. Future growth The growth of Africa's population, particularly in Sub-Saharan Africa, will have the largest impact on global demographics in this century. From 2000 to 2100, it is expected that Africa's population will have increased by a factor of almost five. It overtook Europe in size in the late 1990s, and overtook the Americas a few years later. In contrast to Africa, Europe's population is now in decline, as birth rates are consistently below death rates in many countries, especially in the south and east, resulting in natural population decline. Similarly, the population of the Americas and Asia are expected to go into decline in the second half of this century, and only Oceania's population will still be growing alongside Africa. By 2100, the world's population will have over three billion more than today, with the vast majority of this concentrated in Africa. Demographers predict that climate change is exacerbating many of the challenges that currently hinder progress in Africa, such as political and food instability; if Africa's transition is prolonged, then it may result in further population growth that would place a strain on the region's resources, however, curbing this growth earlier would alleviate some of the pressure created by climate change.

According to latest figures, the Chinese population decreased by 1.39 million to around 1.408 billion people in 2024. After decades of rapid growth, China arrived at the turning point of its demographic development in 2022, which was earlier than expected. The annual population decrease is estimated to remain at moderate levels until around 2030 but to accelerate thereafter. Population development in China China had for a long time been the country with the largest population worldwide, but according to UN estimates, it has been overtaken by India in 2023. As the population in India is still growing, the country is very likely to remain being home of the largest population on earth in the near future. Due to several mechanisms put into place by the Chinese government as well as changing circumstances in the working and social environment of the Chinese people, population growth has subsided over the past decades, displaying an annual population growth rate of -0.1 percent in 2024. Nevertheless, compared to the world population in total, China held a share of about 17 percent of the overall global population in 2024. China's aging population In terms of demographic developments, the birth control efforts of the Chinese government had considerable effects on the demographic pyramid in China. Upon closer examination of the age distribution, a clear trend of an aging population becomes visible. In order to curb the negative effects of an aging population, the Chinese government abolished the one-child policy in 2015, which had been in effect since 1979, and introduced a three-child policy in May 2021. However, many Chinese parents nowadays are reluctant to have a second or third child, as is the case in most of the developed countries in the world. The number of births in China varied in the years following the abolishment of the one-child policy, but did not increase considerably. Among the reasons most prominent for parents not having more children are the rising living costs and costs for child care, growing work pressure, a growing trend towards self-realization and individualism, and changing social behaviors.

The world population surpassed eight billion people in 2022, having doubled from its figure less than 50 years previously. Looking forward, it is projected that the world population will reach nine billion in 2038, and 10 billion in 2060, but it will peak around 10.3 billion in the 2080s before it then goes into decline. Regional variations The global population has seen rapid growth since the early 1800s, due to advances in areas such as food production, healthcare, water safety, education, and infrastructure, however, these changes did not occur at a uniform time or pace across the world. Broadly speaking, the first regions to undergo their demographic transitions were Europe, North America, and Oceania, followed by Latin America and Asia (although Asia's development saw the greatest variation due to its size), while Africa was the last continent to undergo this transformation. Because of these differences, many so-called "advanced" countries are now experiencing population decline, particularly in Europe and East Asia, while the fastest population growth rates are found in Sub-Saharan Africa. In fact, the roughly two billion difference in population between now and the 2080s' peak will be found in Sub-Saharan Africa, which will rise from 1.2 billion to 3.2 billion in this time (although populations in other continents will also fluctuate). Changing projections The United Nations releases their World Population Prospects report every 1-2 years, and this is widely considered the foremost demographic dataset in the world. However, recent years have seen a notable decline in projections when the global population will peak, and at what number. Previous reports in the 2010s had suggested a peak of over 11 billion people, and that population growth would continue into the 2100s, however a sooner and shorter peak is now projected. Reasons for this include a more rapid population decline in East Asia and Europe, particularly China, as well as a prolonged development arc in Sub-Saharan Africa.

The graph shows the population growth in China from 2000 to 2024. In 2024, the Chinese population decreased by about 0.1 percent or 1.39 million to around 1.408 billion people. Declining population growth in China Due to strict birth control measures by the Chinese government as well as changing family and work situations of the Chinese people, population growth has subsided over the past decades. Although the gradual abolition of the one-child policy from 2014 on led to temporarily higher birth figures, growth rates further decreased in recent years. As of 2024, leading countries in population growth could almost exclusively be found on the African continent and the Arabian Peninsula. Nevertheless, as of mid 2024, Asia ranked first by a wide margin among the continents in terms of absolute population. Future development of Chinese population The Chinese population reached a maximum of 1,412.6 million people in 2021 but decreased by 850,000 in 2022 and another 2.08 million in 2023. Until 2022, China had still ranked the world’s most populous country, but it was overtaken by India in 2023. Apart from the population decrease, a clear growth trend in Chinese cities is visible. By 2024, around 67 percent of Chinese people lived in urban areas, compared to merely 36 percent in 2000.

Along the East Asian-Australasian flyway (EAAF), waterbirds are threatened by a wide range of human activities. Studies have shown that wintering populations of many species have declined in Australia and Japan; however, long term data along China’s coast are limited. In this study, we analyzed data collected from monthly bird surveys to quantify population trends of wintering waterbirds from 1998 to 2017 in the Deep Bay area, South China. Of the 42 species studied, 12 declined, while nine increased significantly. Phylogenetic comparative analysis revealed that population trends were negatively correlated to reliance on the Yellow Sea and body size. Further, waterbird species breeding in Southern Siberia declined more than those breeding in East Asia. These findings, coupled with a relatively high number of increasing species, support the continual preservation of wetlands in the Deep Bay area. This study provides another case study showing that data collected from wintering sites provide insights on the threats along migratory pathway and inform conservation actions. As such, we encourage population surveys in the EAAF to continue, particularly along the coast of China.

Migratory birds rely on a habitat network along their migration routes by temporarily occupying stopover sites between breeding and non-breeding grounds. Removal or degradation of stopover sites in a network might impede movement, and thereby reduce migration success and survival. The extent to which the breakdown of migration networks, due to changes in land use, impacts the population sizes of migratory birds is poorly understood. We measured the functional connectivity of migration networks of waterfowl species that migrate over the East Asian-Australasian Flyway from 1992-2015. We analysed the relationship between changes in non-breeding population sizes and changes in functional connectivity, while taking into account other commonly-considered species traits, using a Phylogenetic Linear Mixed Model. We found that population sizes significantly declined with a reduction in the functional connectivity of migration networks; no other predictor variables were important. We conclude that the current decrease in functional connectivity, due to habitat loss and degradation in migration networks, can negatively and crucially impact population sizes of migratory birds. Our findings provide new insights into the underlying mechanisms that affect population trends of migratory birds under environmental changes. Establishment of international agreements leading to the creation of systematic conservation networks associated with migratory species’ distributions and stopover sites may safeguard migratory bird populations.

Reported is the median value and interquartile range.

Reported is the median value and interquartile range.

Mounting observational records demonstrate human-caused faunal decline in recent decades, while accumulating archaeological evidence suggests an early biodiversity impact of human activities during the Holocene. A fundamental question arises concerning whether modern wildlife population declines began during early human disturbance. Here, we performed population genomic analysis of six common forest birds in East Asia to address this question. For five of them, demographic history inference based on 25-33 genomes of each species revealed dramatic population declines by 4-48-fold over millennia (two to five thousand years ago). Nevertheless, ecological niche models predicted extensive range persistence during the Holocene and imply limited demographic impact of historical climate change. Summary statistics further suggest high negative correlations between these population declines and human disturbance intensities and indicate a potential driver of human activities. These findings provi...

In 2020, about 17.9 percent of the population in China had been 60 years and older. This share is growing rapidly and was estimated to reach 40 percent by 2050. China's aging population With China’s boomer generation growing old and life expectancy increasing at the same time, the number of people at an age of 60 or above nearly doubled between 2000 and 2020 and reached around 255 million. This development is even more pronounced for the age group of 80 and above, which nearly tripled and is expected to reach a size of roughly 132 million in 2050, up from only 32 million in 2020. At the same time, the share of the working-age population is forecasted to decrease gradually from 64 percent of the total population in 2020 to around 50 percent in 2050, which could pose a heavy economic strain on the social security system. The old-age dependency ratio, which denotes the relation of the old-age to the working-age population, is estimated to grow from 18.2 percent in 2020 to more than 50 percent in 2050, implying that by then, statistically, two working-age adults would have to support one elderly. Strain on the social security net During the last 15 years, China's government has successfully increased the coverage of the pension insurance and health insurance. Today, most of the people are covered by some kind of social insurance. Conditions in the pension system are generous, with a regular retirement age for males at 60 years and women at 50 or 55. With the number of retirees increasing quickly, the social insurance system is now under pressure. From an economic point of view, improving the productivity of China's economy would be the primary choice for mitigating alleged inconsistencies of the system. However, without increasing the burden on the working people while tightening payment conditions, balancing the social security net could prove to be challenging.

Loss and/or deterioration of refuelling habitats have caused population declines in many migratory bird species, but whether this results from unequal mortality among individuals varying in migration traits remains to be shown. Based on 13 years of body mass and size data of great knots (Calidris tenuirostris) at a stopover site of the Yellow Sea, combined with resightings of individuals marked at this stopover site along the East Asian-Australasian Flyway, we assessed year to year changes in annual apparent survival rates, and how apparent survival differed between migration phenotypes (their i.e. migration timing and fuel stores). The measurements occurred over a period of habitat loss and/or deterioration in this flyway. We found that the annual apparent survival rates of great knots rapidly declined from 2006 to 2018, late-arriving individuals with small fuel stores exhibiting the lowest apparent survival rate. There was an advancement in mean arrival date and an increase in the mea...

In 1800, the population of Japan was just over 30 million, a figure which would grow by just two million in the first half of the 19th century. However, with the fall of the Tokugawa shogunate and the restoration of the emperor in the Meiji Restoration of 1868, Japan would begin transforming from an isolated feudal island, to a modernized empire built on Western models. The Meiji period would see a rapid rise in the population of Japan, as industrialization and advancements in healthcare lead to a significant reduction in child mortality rates, while the creation overseas colonies would lead to a strong economic boom. However, this growth would slow beginning in 1937, as Japan entered a prolonged war with the Republic of China, which later grew into a major theater of the Second World War. The war was eventually brought to Japan's home front, with the escalation of Allied air raids on Japanese urban centers from 1944 onwards (Tokyo was the most-bombed city of the Second World War). By the war's end in 1945 and the subsequent occupation of the island by the Allied military, Japan had suffered over two and a half million military fatalities, and over one million civilian deaths.

The population figures of Japan were quick to recover, as the post-war “economic miracle” would see an unprecedented expansion of the Japanese economy, and would lead to the country becoming one of the first fully industrialized nations in East Asia. As living standards rose, the population of Japan would increase from 77 million in 1945, to over 127 million by the end of the century. However, growth would begin to slow in the late 1980s, as birth rates and migration rates fell, and Japan eventually grew to have one of the oldest populations in the world. The population would peak in 2008 at just over 128 million, but has consistently fallen each year since then, as the fertility rate of the country remains below replacement level (despite government initiatives to counter this) and the country's immigrant population remains relatively stable. The population of Japan is expected to continue its decline in the coming years, and in 2020, it is estimated that approximately 126 million people inhabit the island country.

The region of present-day China has historically been the most populous region in the world; however, its population development has fluctuated throughout history. In 2022, China was overtaken as the most populous country in the world, and current projections suggest its population is heading for a rapid decline in the coming decades. Transitions of power lead to mortality The source suggests that conflict, and the diseases brought with it, were the major obstacles to population growth throughout most of the Common Era, particularly during transitions of power between various dynasties and rulers. It estimates that the total population fell by approximately 30 million people during the 14th century due to the impact of Mongol invasions, which inflicted heavy losses on the northern population through conflict, enslavement, food instability, and the introduction of bubonic plague. Between 1850 and 1870, the total population fell once more, by more than 50 million people, through further conflict, famine and disease; the most notable of these was the Taiping Rebellion, although the Miao an Panthay Rebellions, and the Dungan Revolt, also had large death tolls. The third plague pandemic also originated in Yunnan in 1855, which killed approximately two million people in China. 20th and 21st centuries There were additional conflicts at the turn of the 20th century, which had significant geopolitical consequences for China, but did not result in the same high levels of mortality seen previously. It was not until the overlapping Chinese Civil War (1927-1949) and Second World War (1937-1945) where the death tolls reached approximately 10 and 20 million respectively. Additionally, as China attempted to industrialize during the Great Leap Forward (1958-1962), economic and agricultural mismanagement resulted in the deaths of tens of millions (possibly as many as 55 million) in less than four years, during the Great Chinese Famine. This mortality is not observable on the given dataset, due to the rapidity of China's demographic transition over the entire period; this saw improvements in healthcare, sanitation, and infrastructure result in sweeping changes across the population. The early 2020s marked some significant milestones in China's demographics, where it was overtaken by India as the world's most populous country, and its population also went into decline. Current projections suggest that China is heading for a "demographic disaster", as its rapidly aging population is placing significant burdens on China's economy, government, and society. In stark contrast to the restrictive "one-child policy" of the past, the government has introduced a series of pro-fertility incentives for couples to have larger families, although the impact of these policies are yet to materialize. If these current projections come true, then China's population may be around half its current size by the end of the century.

In 2023, about ***** million people in China were estimated by the UN to be at a working age between 15 and 64 years. After a steep increase in the second half of the 20th century, the size of the working-age population reached a turning point in 2015 and figures started to decrease thereafter. Changes in the working-age population China's demographic development is characterized by a rapid change from a high fertility rate to a low one. This has caused the development of an arc shaped graph of the working age population: quickly increasing numbers before 2010, a gradual turn with a minor second peak until around 2027, and a steep decline thereafter. The expected second maximum of the graph results from the abolishment of birth control measures after 2010, which proved less successful in increasing birth figures than expected. The same turn can be seen in the number of people eligible for work, with an accelerated downturn in the years of the coronavirus pandemic, where many people left the labor force. It is very likely that the size of the labor force will rebound slightly in the upcoming years, but the extent of the rebound, which parallels the second maximum of the working age population, might be limited. China's labor market China's labor market was once defined by its abundant and cheap labor force, but competition for talent has been getting increasingly tense in recent years. This development is very likely to further intensify and extend itself into the less skilled ranks of the labor market. As the number of people who fall within the retirement age group is increasing and adding to the burden on the economy, steps to keep labor participation high are necessary. Raising the retirement age and providing incentives to stay in the labor force, are measures being implemented by Chinese government. Strategies to increase labor productivity would be ideal to mitigate the pressure on the Chinese economy, however, realizing such strategies is challenging.

ObjectiveLower respiratory infections (LRIs) remain a major global health challenge. Although the overall burden has declined, cross-country differences in long-term trends, age–sex patterns, and risk factors in East Asia are not well characterized. This study provides the first systematic comparison of long-term LRI trends across five East Asian countries—China, Japan, Republic of Korea, Democratic People’s Republic of Korea, and Mongolia—using Global Burden of Disease Study 2021 (GBD 2021) data.MethodsWe analyzed LRI incidence, mortality, and disability-adjusted life years (DALYs) from 1990 to 2021. Temporal trends were quantified by estimated annual percentage change (EAPC). We combined decomposition analysis and autoregressive integrated moving average (ARIMA) forecasting to quantify the relative contributions of population growth, aging, and epidemiological changes, and to project future trajectories. Risk factor attribution was evaluated using population-attributable fractions, and age–sex patterns were compared across countries.ResultsFrom 1990 to 2021, all five countries showed substantial reductions in age-standardized incidence and mortality, with Mongolia and China achieving the steepest declines. The burden shifted from children under five to older adults, particularly those aged ≥70 years, a novel epidemiological transition most evident in Japan and Korea. Decomposition indicated that epidemiological improvements were the primary drivers of mortality reductions, while population aging in Japan and Korea partially counteracted these improvements. Forecasts suggest continued declines in incidence and mortality across most countries, though Japan may experience a plateau in mortality.ConclusionThis study provides the first systematic comparison of long-term LRI trends across five East Asian countries. While the overall burden has declined, population aging, air pollution, and smoking are emerging challenges. By combining decomposition and ARIMA forecasting, our findings highlight the shift from children to older adults and offer timely evidence for age-sensitive, country-specific interventions such as vaccination for older adults, environmental regulation, and tobacco control.

In 2024, approximately 965.65 million people in China were of working age between 15 and 64 years. This was equal to a 68.3 percent share of the total population. Age groups between 30 and 59 years represented the largest age cohorts in the Chinese population pyramid. Age demographics in China The change in China’s age distribution over time displayed in the given statistic illustrates the unfolding of an aging population. As the fertility rate in China declined and life expectancy increased, the only age groups that have been growing over the last three decades were those of old people. In contrast, the number of children decreased gradually between 1995 and 2010 and remained comparatively low thereafter. According to the data provided by the National Bureau of Statistics of China, which has not been revised for years before the 2020 census, the size of the working age population declined in 2014 for the first time and entered a downward trajectory thereafter. This development has extended itself into the total population, which has shrunk in 2022 for the first time in decades. Future age development As the fertility rate in China is expected to remain below the reproductive level, the Chinese society will very likely age rapidly. According to UN data, which is based on figures slightly different from the Chinese official numbers, the share of the population above 60 years of age is projected to reach nearly 40 percent in 2050, while the share of children is expected to remain stable. This will lead to an increased burden of the old-age population on the social security system, illustrated by an old-age dependency ratio peaking at nearly 106 percent in 2090. This means that by then, ten working-age adults would have to support nine elderly people.

Annotated R code of steps taken to generate geolocator-derived stationary estimates and refine Dunlin migration tracks along the East Asian-Australasian Flyway. (HTML)

Site locations are in Fig 1.

In 2024, the average number of children born per 1,000 people in China ranged at ****. The birth rate has dropped considerably since 2016, and the number of births fell below the number of deaths in 2022 for the first time in decades, leading to a negative population growth rate. Recent development of the birth rate Similar to most East-Asian countries and territories, demographics in China today are characterized by a very low fertility rate. As low fertility in the long-term limits economic growth and leads to heavy strains on the pension and health systems, the Chinese government decided to support childbirth by gradually relaxing strict birth control measures, that had been in place for three decades. However, the effect of this policy change was considerably smaller than expected. The birth rate increased from **** births per 1,000 inhabitants in 2010 to ***** births in 2012 and remained on a higher level for a couple of years, but then dropped again to a new low in 2018. This illustrates that other factors constrain the number of births today. These factors are most probably similar to those experienced in other developed countries as well: women preferring career opportunities over maternity, high costs for bringing up children, and changed social norms, to name only the most important ones. Future demographic prospects Between 2020 and 2023, the birth rate in China dropped to formerly unknown lows, most probably influenced by the coronavirus pandemic. As all COVID-19 restrictions were lifted by the end of 2022, births figures showed a catch-up effect in 2024. However, the scope of the rebound might be limited. A population breakdown by five-year age groups indicates that the drop in the number of births is also related to a shrinking number of people with child-bearing age. The age groups between 15 and 29 years today are considerably smaller than those between 30 and 44, leaving less space for the birth rate to increase. This effect is exacerbated by a considerable gender gap within younger age groups in China, with the number of females being much lower than that of males.