|
Population Pressure
Population pressure, a term summarizing the stress brought about by an excessive population density and its consequences, is used both in conjunction with human overpopulation and with other animal populations that suffer from too many individuals per area (or volume in the case of aquatic organisms). In the case of humans, absolute numbers of individuals may lead to population pressure, but the same is true for overexploitation and overconsumption of available resources and ensuing environmental degradation by otherwise-normal population densities. Similarly, when the carrying capacity of the environment goes down, unchanged population numbers may prove too high and again produce significant pressure. "Pressure" is to be understood metaphorically and hints at the analogy between a gas or fluid that under pressure will tend to escape a bounded container. Similarly, "population pressure" in animal populations in general usually leads to migration activity, and in humans, it may addi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Population Density
Population density (in agriculture: Stock (other), standing stock or plant density) is a measurement of population per unit land area. It is mostly applied to humans, but sometimes to other living organisms too. It is a key geographical term.Matt RosenberPopulation Density Geography.about.com. March 2, 2011. Retrieved on December 10, 2011. In simple terms, population density refers to the number of people living in an area per square kilometre, or other unit of land area. Biological population densities Population density is population divided by total land area, sometimes including seas and oceans, as appropriate. Low densities may cause an extinction vortex and further reduce fertility. This is called the Allee effect after the scientist who identified it. Examples of the causes of reduced fertility in low population densities are * Increased problems with locating sexual mates * Increased inbreeding Human densities Population density is the number of people pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Population Decline
A population decline (also sometimes called underpopulation, depopulation, or population collapse) in humans is a reduction in a human population size. Over the long term, stretching from prehistory to the present, Earth's total human population has continued to grow; however, current projections suggest that this long-term trend of steady population growth may be coming to an end. Until the beginning of the Industrial Revolution, global population grew very slowly. After about 1800, the growth rate accelerated to a peak of 2.09% annually during the 1967–1969 period, but since then, due to the worldwide collapse of the total fertility rate, it has declined to 1.05% as of 2020. The global growth rate in absolute numbers accelerated to a peak of 92.9 million in 1988, but has declined to 81.3 million in 2020. Long-term projections indicate that the growth rate of the human population of this planet will continue to decline and that by the end of the 21st century, it will reach ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sustainable Population
Sustainable population refers to a proposed sustainable human population of Earth or a particular region of Earth, such as a nation or continent. Estimates vary widely, with estimates based on different figures ranging from 0.65 billion people to 98 billion, with 8 billion people being a typical estimate. Projections of population growth, evaluations of overconsumption and associated human pressures on the environment have led to some to advocate for what they consider a sustainable population. Proposed policy solutions vary, including sustainable development, female education, family planning and broad human population planning. Emerging economies like those of China and India aspire to the living standards of the Western world, as does the non-industrialized world in general. As of 2022, China and India account for most of the population in Asia, with more than 1.4 billion each. It is the combination of population increase in the developing world and unsustainable consumption l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Overshoot (population)
In environmental science, the concept of overshoot means demand in excess of regeneration. It can apply to animal populations and people. Environmental science studies to what extent human populations through their resource consumption have risen above the sustainable use of resources. For people, "overshoot" is that portion of their demand or ecological footprint which must be eliminated to be sustainable. Excessive demand leading to overshoot is driven by both consumption and population. A decline in population as a consequence of overshoot has been termed 'collapse'. The trajectory undergone by such a population has been called 'overshoot-and-collapse'. A collapse, as much as overshoot, can be the result of different conditions, a particular but not synonymous case of collapse is the Malthusian catastrophe. Overshoot can occur due to lag effects. Reproduction rates may remain high relative to the death rate. Entire ecosystems may be severely affected and sometimes reduced to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Population Growth
Population growth is the increase in the number of people in a population or dispersed group. Actual global human population growth amounts to around 83 million annually, or 1.1% per year. The global population has grown from 1 billion in 1800 to 7.9 billion in 2020. The UN projected population to keep growing, and estimates have put the total population at 8.6 billion by mid-2030, 9.8 billion by mid-2050 and 11.2 billion by 2100. However, some academics outside the UN have increasingly developed human population models that account for additional downward pressures on population growth; in such a scenario population would peak before 2100. World human population has been growing since the end of the Black Death, around the year 1350. A mix of technological advancement that improved agricultural productivity and sanitation and medical advancement that reduced mortality increased population growth. In some geographies, this has slowed through the process called the demographic t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malthusian Catastrophe
Malthusianism is the idea that population growth is potentially exponential while the growth of the food supply or other resources is linear, which eventually reduces living standards to the point of triggering a population die off. This event, called a Malthusian catastrophe (also known as a Malthusian trap, population trap, Malthusian check, Malthusian crisis, Malthusian spectre, or Malthusian crunch) occurs when population growth outpaces agricultural production, causing famine or war, resulting in poverty and depopulation. Such a catastrophe inevitably has the effect of forcing the population to "correct" back to a lower, more easily sustainable level (quite rapidly, due to the potential severity and unpredictable results of the mitigating factors involved, as compared to the relatively slow time scales and well-understood processes governing unchecked growth or growth affected by preventive checks). Malthusianism has been linked to a variety of political and social movement ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Struggle For Existence
The concept of the struggle for existence concerns the competition or battle for resources needed to live. It can refer to human society, or to organisms in nature. The concept is ancient, and the term ''struggle for existence'' was in use by the end of the 18th century. From the 17th century onwards the concept was associated with a population exceeding resources, an issue shown starkly in Thomas Robert Malthus’ ''An Essay on the Principle of Population'' which drew on Benjamin Franklin's '' Observations Concerning the Increase of Mankind, Peopling of Countries, etc.''. Charles Darwin used the phrase "struggle for existence" in a broader sense, and chose the term as the title to the third chapter of ''On the Origin of Species'' published in 1859. Using Malthus's idea of the struggle for existence, Darwin was able to develop his view of adaptation, which was highly influential in the formulation of the theory of natural selection.Ospovat, Dov. ''The Development of Darwin's Theory ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Darwin
Charles Robert Darwin ( ; 12 February 1809 – 19 April 1882) was an English naturalist, geologist, and biologist, widely known for his contributions to evolutionary biology. His proposition that all species of life have descended from a common ancestor is now generally accepted and considered a fundamental concept in science. In a joint publication with Alfred Russel Wallace, he introduced his scientific theory that this branching pattern of evolution resulted from a process he called natural selection, in which the struggle for existence has a similar effect to the artificial selection involved in selective breeding. Darwin has been described as one of the most influential figures in human history and was honoured by burial in Westminster Abbey. Darwin's early interest in nature led him to neglect his medical education at the University of Edinburgh; instead, he helped to investigate marine invertebrates. His studies at the University of Cambridge's Christ's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
An Essay On The Principle Of Population
An, AN, aN, or an may refer to: Businesses and organizations * Airlinair (IATA airline code AN) * Alleanza Nazionale, a former political party in Italy * AnimeNEXT, an annual anime convention located in New Jersey * Anime North, a Canadian anime convention * Ansett Australia, a major Australian airline group that is now defunct (IATA designator AN) * Apalachicola Northern Railroad (reporting mark AN) 1903–2002 ** AN Railway, a successor company, 2002– * Aryan Nations, a white supremacist religious organization * Australian National Railways Commission, an Australian rail operator from 1975 until 1987 * Antonov, a Ukrainian (formerly Soviet) aircraft manufacturing and services company, as a model prefix Entertainment and media * Antv, an Indonesian television network * ''Astronomische Nachrichten'', or ''Astronomical Notes'', an international astronomy journal * ''Avisa Nordland'', a Norwegian newspaper * '' Sweet Bean'' (あん), a 2015 Japanese film also known as ' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thomas Malthus
Thomas Robert Malthus (; 13/14 February 1766 – 29 December 1834) was an English cleric, scholar and influential economist in the fields of political economy and demography. In his 1798 book ''An Essay on the Principle of Population'', Malthus observed that an increase in a nation's food production improved the well-being of the population, but the improvement was temporary because it led to population growth, which in turn restored the original per capita production level. In other words, humans had a propensity to utilize abundance for population growth rather than for maintaining a high standard of living, a view that has become known as the "Malthusian trap" or the "Malthusian spectre". Populations had a tendency to grow until the lower class suffered hardship, want and greater susceptibility to war famine and disease, a pessimistic view that is sometimes referred to as a Malthusian catastrophe. Malthus wrote in opposition to the popular view in 18th-century Europe th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Extinction
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point. Because a species' potential range may be very large, determining this moment is difficult, and is usually done retrospectively. This difficulty leads to phenomena such as Lazarus taxa, where a species presumed extinct abruptly "reappears" (typically in the fossil record) after a period of apparent absence. More than 99% of all species that ever lived on Earth, amounting to over five billion species, are estimated to have died out. It is estimated that there are currently around 8.7 million species of eukaryote globally, and possibly many times more if microorganisms, like bacteria, are included. Notable extinct animal species include non-avian dinosaurs, saber-toothed cats, dodos, m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Land Development
Land development is the alteration of landscape in any number of ways such as: * Changing landforms from a natural or semi-natural state for a purpose such as agriculture or housing * Subdividing real estate into lots, typically for the purpose of building homes * Real estate development or changing its purpose, for example by converting an unused factory complex into a condominium. Economic aspects In an economic context, land development is also sometimes advertised as land improvement or land amelioration. It refers to investment making land more usable by humans. For accounting purposes it refers to any variety of projects that increase the value of the process . Most are depreciable, but some land improvements are not able to be depreciated because a useful life cannot be determined. Home building and containment are two of the most common and the oldest types of development. In an urban context, land development furthermore includes: * Road construction ** Acces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Extinction")
