Geography is a field of science devoted to the study of the lands, features and phenomena of the Earth and planets. The first person to use the word γεωγραφία was Eratosthenes. Geography is an all-encompassing discipline that seeks an understanding of Earth and its human and natural complexities—not where objects are, but how they have changed and come to be. Geography is defined in terms of two branches: human geography and physical geography. Human geography deals with the study of people and their communities, cultures and interactions with the environment by studying their relations with and across space and place. Physical geography deals with the study of processes and patterns in the natural environment like the atmosphere, hydrosphere and geosphere; the four historical traditions in geographical research are: spatial analyses of natural and the human phenomena, area studies of places and regions, studies of human-land relationships, the Earth sciences. Geography has been called "the world discipline" and "the bridge between the human and the physical sciences".
Geography is a systematic study of its features. Traditionally, geography has been associated with place names. Although many geographers are trained in toponymy and cartology, this is not their main preoccupation. Geographers study the space and the temporal database distribution of phenomena and features as well as the interaction of humans and their environment; because space and place affect a variety of topics, such as economics, climate and animals, geography is interdisciplinary. The interdisciplinary nature of the geographical approach depends on an attentiveness to the relationship between physical and human phenomena and its spatial patterns. Names of places...are not geography...know by heart a whole gazetteer full of them would not, in itself, constitute anyone a geographer. Geography has higher aims than this: it seeks to classify phenomena, to compare, to generalize, to ascend from effects to causes, and, in doing so, to trace out the laws of nature and to mark their influences upon man.
This is ` a description of the world' --. In a word Geography is a Science—a thing not of mere names but of argument and reason, of cause and effect. Just as all phenomena exist in time and thus have a history, they exist in space and have a geography. Geography as a discipline can be split broadly into two main subsidiary fields: human geography and physical geography; the former focuses on the built environment and how humans create, view and influence space. The latter examines the natural environment, how organisms, soil and landforms produce and interact; the difference between these approaches led to a third field, environmental geography, which combines physical and human geography and concerns the interactions between the environment and humans. Physical geography focuses on geography as an Earth science, it aims to understand the physical problems and the issues of lithosphere, atmosphere and global flora and fauna patterns. Physical geography can be divided into many broad categories, including: Human geography is a branch of geography that focuses on the study of patterns and processes that shape the human society.
It encompasses the human, cultural and economic aspects. Human geography can be divided into many broad categories, such as: Various approaches to the study of human geography have arisen through time and include: Behavioral geography Feminist geography Culture theory Geosophy Environmental geography is concerned with the description of the spatial interactions between humans and the natural world, it requires an understanding of the traditional aspects of physical and human geography, as well as the ways that human societies conceptualize the environment. Environmental geography has emerged as a bridge between the human and the physical geography, as a result of the increasing specialisation of the two sub-fields. Furthermore, as human relationship with the environment has changed as a result of globalization and technological change, a new approach was needed to understand the changing and dynamic relationship. Examples of areas of research in the environmental geography include: emergency management, environmental management and political ecology.
Geomatics is concerned with the application of computers to the traditional spatial techniques used in cartography and topography. Geomatics emerged from the quantitative revolution in geography in the mid-1950s. Today, geomatics methods include spatial analysis, geographic information systems, remote sensing, global positioning systems. Geomatics has led to a revitalization of some geography departments in Northern America where the subject had a declining status during the 1950s. Regional geography is concerned with the description of the unique characteristics of a particular region such as its natural or human elements; the main aim is to understand, or define the uniqueness, or character of a particular region that consists of natural as well as human elements. Attention is paid to regionalization, which covers the proper techniques of space delimitation into regions. Urban planning, regional planning, spatial planning: Use the science of geography to assist in determining how to develop the land to meet particular criteria, such as safety, economic opportunities, the preservation of the built or natural heritage, so on.
The planning of towns, c
An encyclopedia or encyclopædia is a reference work or compendium providing summaries of knowledge from either all branches or from a particular field or discipline. Encyclopedias are divided into articles or entries that are arranged alphabetically by article name and sometimes by thematic categories. Encyclopedia entries are more detailed than those in most dictionaries. Speaking, unlike dictionary entries—which focus on linguistic information about words, such as their etymology, pronunciation and grammatical forms—encyclopedia articles focus on factual information concerning the subject named in the article's title. Encyclopedias have existed for around 2,000 years and have evolved during that time as regards language, intent, cultural perceptions, authorship and the technologies available for their production and distribution; as a valued source of reliable information compiled by experts, printed versions found a prominent place in libraries and other educational institutions. The appearance of digital and open-source versions in the 20th century has vastly expanded the accessibility, authorship and variety of encyclopedia entries and called into question the idea of what an encyclopedia is and the relevance of applying to such dynamic productions the traditional criteria for assembling and evaluating print encyclopedias.
The word encyclopedia comes from the Koine Greek ἐγκύκλιος παιδεία, transliterated enkyklios paideia, meaning "general education" from enkyklios, meaning "circular, required general" and paideia, meaning "education, rearing of a child". However, the two separate words were reduced to a single word due to a scribal error by copyists of a Latin manuscript edition of Quintillian in 1470; the copyists took this phrase to be a single Greek word, with the same meaning, this spurious Greek word became the New Latin word "encyclopaedia", which in turn came into English. Because of this compounded word, fifteenth century readers and since have and incorrectly, thought that the Roman authors Quintillian and Pliny described an ancient genre. In the sixteenth century there was a level of ambiguity as to; as several titles illustrate, there was not a settled notion about its spelling nor its status as a noun. For example: Jacobus Philomusus's Margarita philosophica encyclopaediam exhibens, it is only with Pavao Skalić and his Encyclopediae seu orbis disciplinarum tam sacrarum quam profanarum epistemon that the term became first recognized as a noun.
There have been two examples of the oldest vernacular use of the compounded word. In 1490, Franciscus Puccius wrote a letter to Politianus thanking him for his Miscellanea, calling it an encyclopedia. More François Rabelais is cited for his use of the term in Pantagruel. Several encyclopedias have names that include the suffix -pedia, to mark the text as belonging to the genre of encyclopedias. For example, Banglapedia. Today in English, the word is most spelled encyclopedia, though encyclopaedia is used in Britain; the modern encyclopedia was developed from the dictionary in the 18th century. Both encyclopedias and dictionaries have been researched and written by well-educated, well-informed content experts, but they are different in structure. A dictionary is a linguistic work which focuses on alphabetical listing of words and their definitions. Synonymous words and those related by the subject matter are to be found scattered around the dictionary, giving no obvious place for in-depth treatment.
Thus, a dictionary provides limited information, analysis or background for the word defined. While it may offer a definition, it may leave the reader lacking in understanding the meaning, significance or limitations of a term, how the term relates to a broader field of knowledge. An encyclopedia is, not written in order to convince, although one of its goals is indeed to convince its reader of its own veracity. To address those needs, an encyclopedia article is not limited to simple definitions, is not limited to defining an individual word, but provides a more extensive meaning for a subject or discipline. In addition to defining and listing synonymous terms for the topic, the article is able to treat the topic's more extensive meaning in more depth and convey the most relevant accumulated knowledge on that subject. An encyclopedia article often includes many maps and illustrations, as well as bibliography and statistics. Four major elements define an encyclopedia: its subject matter, its scope, its method of organization, its method of production: Encyclopedias can be general, containing articles on topics in every field
Life expectancy is a statistical measure of the average time an organism is expected to live, based on the year of its birth, its current age and other demographic factors including gender. The most used measure of life expectancy is at birth, which can be defined in two ways. Cohort LEB is the mean length of life of an actual birth cohort and can be computed only for cohorts born many decades ago, so that all their members have died. Period LEB is the mean length of life of a hypothetical cohort assumed to be exposed, from birth through death, to the mortality rates observed at a given year. National LEB figures reported by statistical national agencies and international organizations are indeed estimates of period LEB. In the Bronze Age and the Iron Age, LEB was 26 years. For recent years, LEB in Swaziland is about 49, while LEB in Japan is about 83; the combination of high infant mortality and deaths in young adulthood from accidents, plagues and childbirth before modern medicine was available lowers LEB.
For example, a society with a LEB of 40 may have few people dying at 40: most will die before 30 or after 55. In populations with high infant mortality rates, LEB is sensitive to the rate of death in the first few years of life; because of this sensitivity to infant mortality, LEB can be subjected to gross misinterpretation, leading one to believe that a population with a low LEB will have a small proportion of older people. Another measure, such as life expectancy at age 5, can be used to exclude the effect of infant mortality to provide a simple measure of overall mortality rates other than in early childhood. Aggregate population measures, such as the proportion of the population in various age groups, should be used along individual-based measures like formal life expectancy when analyzing population structure and dynamics. However, pre-modern societies still had universally higher mortality rates and universally lower life expectancies at every age for both genders, this example was rare.
In societies with life expectancies of 30, for instance, a 40 year remaining timespan at age 5 may not be uncommon, but a 60 year one was. Mathematically, life expectancy is the mean number of years of life remaining at a given age, assuming age-specific mortality rates remain at their most measured levels, it is denoted by e x, which means the mean number of subsequent years of life for someone now aged x, according to a particular mortality experience. Longevity, maximum lifespan, life expectancy are not synonyms. Life expectancy is defined statistically as the mean number of years remaining for an individual or a group of people at a given age. Longevity refers to the characteristics of the long life span of some members of a population. Maximum lifespan is the age at death for the longest-lived individual of a species. Moreover, because life expectancy is an average, a particular person may die many years before or many years after the "expected" survival; the term "maximum life span" is more related to longevity.
Life expectancy is used in plant or animal ecology. The term life expectancy may be used in the context of manufactured objects, but the related term shelf life is used for consumer products, the terms "mean time to breakdown" and "mean time between failures" are used in engineering. Records of human lifespan above age 100 are susceptible to errors. For example, the previous world-record holder for human lifespan, Carrie White, was uncovered as a simple typographic error after more than two decades. Therefore, the capacity for equivalent hidden errors make maximum lifespan records dubious; the oldest confirmed recorded age for any human is 122 years, reached by Jeanne Calment who lived between 1875 and 1997. This is referred to as the "maximum life span", the upper boundary of life, the maximum number of years any human is known to have lived. A theoretical study shows that the maximum life expectancy at birth is limited by the human life characteristic value δ, around 104 years. According to a study by biologists Bryan G. Hughes and Siegfried Hekimi, there is no evidence for limit on human lifespan.
However, this view has been questioned on the basis of error patterns. The following information is derived from the 1961 Encyclopædia Britannica and other sources, some with questionable accuracy. Unless otherwise stated, it represents estimates of the life expectancies of the world population as a whole. In many instances, life expectancy varied according to class and gender. Life expectancy at birth takes account of infant mortality but not prenatal mortality. Life expectancy increases with age as the individual survives the higher mortality rates associated with childhood. For instance, the table above listed the life expectancy at birth among 13th-century English nobles at 30. Having survived until the age of 21, a male member of the English aristocracy in this period could expect to live: 1200–1300: to age 64 1300–1400: to age 45 1400–1500: to age 69 1500–1550: to age 71In a similar way, the life expectancy of scholars in the Medieval Islamic world was 59–84.3 years.17th-century English life expectancy was only about 35 years because infant and child mortality remained high.
Life expectancy was under 25 years in the early Colony of Virginia, in seventeenth-century New England, about 40 percent died befor
In ecology, a habitat is the type of natural environment in which a particular species of organism lives. It is characterized by both biological features. A species' habitat is those places where it can find food, shelter and mates for reproduction; the physical factors are for example soil, range of temperature, light intensity as well as biotic factors such as the availability of food and the presence or absence of predators. Every organism has certain habitat needs for the conditions in which it will thrive, but some are tolerant of wide variations while others are specific in their requirements. A habitat is not a geographical area, it can be the interior of a stem, a rotten log, a rock or a clump of moss, for a parasitic organism it is the body of its host, part of the host's body such as the digestive tract, or a single cell within the host's body. Habitat types include polar, temperate and tropical; the terrestrial vegetation type may be forest, grassland, semi-arid or desert. Fresh water habitats include marshes, rivers and ponds, marine habitats include salt marshes, the coast, the intertidal zone, reefs, the open sea, the sea bed, deep water and submarine vents.
Habitats change over time. This may be due to a violent event such as the eruption of a volcano, an earthquake, a tsunami, a wildfire or a change in oceanic currents. Other changes come as a direct result of human activities; the introduction of alien species can have a devastating effect on native wildlife, through increased predation, through competition for resources or through the introduction of pests and diseases to which the native species have no immunity. The word "habitat" has been in use since about 1755 and derives from the Latin habitāre, to inhabit, from habēre, to have or to hold. Habitat can be defined as the natural environment of an organism, the type of place in which it is natural for it to live and grow, it is similar in meaning to a biotope. The chief environmental factors affecting the distribution of living organisms are temperature, climate, soil type and light intensity, the presence or absence of all the requirements that the organism needs to sustain it. Speaking, animal communities are reliant on specific types of plant communities.
Some plants and animals are generalists, their habitat requirements are met in a wide range of locations. The small white butterfly for example is found on all the continents of the world apart from Antarctica, its larvae feed on a wide range of Brassicas and various other plant species, it thrives in any open location with diverse plant associations. The large blue butterfly is much more specific in its requirements. Disturbance is important in the creation of biodiverse habitats. In the absence of disturbance, a climax vegetation cover develops that prevents the establishment of other species. Wildflower meadows are sometimes created by conservationists but most of the flowering plants used are either annuals or biennials and disappear after a few years in the absence of patches of bare ground on which their seedlings can grow. Lightning strikes and toppled trees in tropical forests allow species richness to be maintained as pioneering species move in to fill the gaps created. Coastal habitats can become dominated by kelp until the seabed is disturbed by a storm and the algae swept away, or shifting sediment exposes new areas for colonisation.
Another cause of disturbance is when an area may be overwhelmed by an invasive introduced species, not kept under control by natural enemies in its new habitat. Terrestrial habitat types include forests, grasslands and deserts. Within these broad biomes are more specific habitats with varying climate types, temperature regimes, soils and vegetation types. Many of these habitats grade into each other and each one has its own typical communities of plants and animals. A habitat may suit a particular species well, but its presence or absence at any particular location depends to some extent on chance, on its dispersal abilities and its efficiency as a coloniser. Freshwater habitats include rivers, lakes, ponds and bogs. Although some organisms are found across most of these habitats, the majority have more specific requirements; the water velocity, its temperature and oxygen saturation are important factors, but in river systems, there are fast and slow sections, pools and backwaters which provide a range of habitats.
Aquatic plants can be floating, semi-submerged, submerged or grow in permanently or temporarily saturated soils besides bodies of water. Marginal plants provide important habitat for both invertebrates and vertebrates, submerged plants provide oxygenation of the water, absorb nutrients and play a part in the reduction of pollution. Marine habitats include brackish water, bays, the open sea, the intertidal zone, the sea bed and deep / shallow water zones. Further variations include rock pools, sand banks, brackish lagoons and pebbly beaches, seagrass beds, all supporting their own flora and fauna; the benth
Reproduction is the biological process by which new individual organisms – "offspring" – are produced from their "parents". Reproduction is a fundamental feature of all known life. There are two forms of reproduction: sexual. In asexual reproduction, an organism can reproduce without the involvement of another organism. Asexual reproduction is not limited to single-celled organisms; the cloning of an organism is a form of asexual reproduction. By asexual reproduction, an organism creates a genetically identical copy of itself; the evolution of sexual reproduction is a major puzzle for biologists. The two-fold cost of sexual reproduction is that only 50% of organisms reproduce and organisms only pass on 50% of their genes. Sexual reproduction requires the sexual interaction of two specialized organisms, called gametes, which contain half the number of chromosomes of normal cells and are created by meiosis, with a male fertilizing a female of the same species to create a fertilized zygote; this produces offspring organisms whose genetic characteristics are derived from those of the two parental organisms.
Asexual reproduction is a process by which organisms create genetically similar or identical copies of themselves without the contribution of genetic material from another organism. Bacteria divide asexually via binary fission; these organisms do not possess different sexes, they are capable of "splitting" themselves into two or more copies of themselves. Most plants have the ability to reproduce asexually and the ant species Mycocepurus smithii is thought to reproduce by asexual means; some species that are capable of reproducing asexually, like hydra and jellyfish, may reproduce sexually. For instance, most plants are capable of vegetative reproduction—reproduction without seeds or spores—but can reproduce sexually. Bacteria may exchange genetic information by conjugation. Other ways of asexual reproduction include parthenogenesis and spore formation that involves only mitosis. Parthenogenesis is the development of embryo or seed without fertilization by a male. Parthenogenesis occurs in some species, including lower plants and vertebrates.
It is sometimes used to describe reproduction modes in hermaphroditic species which can self-fertilize. Sexual reproduction is a biological process that creates a new organism by combining the genetic material of two organisms in a process that starts with meiosis, a specialized type of cell division; each of two parent organisms contributes half of the offspring's genetic makeup by creating haploid gametes. Most organisms form two different types of gametes. In these anisogamous species, the two sexes are referred to as female. In isogamous species, the gametes are similar or identical in form, but may have separable properties and may be given other different names. For example, in the green alga, Chlamydomonas reinhardtii, there are so-called "plus" and "minus" gametes. A few types of organisms, such as many fungi and the ciliate Paramecium aurelia, have more than two "sexes", called syngens. Most animals and plants reproduce sexually. Sexually reproducing organisms have different sets of genes for every trait.
Offspring inherit one allele for each trait from each parent. Thus, offspring have a combination of the parents' genes, it is believed that "the masking of deleterious alleles favors the evolution of a dominant diploid phase in organisms that alternate between haploid and diploid phases" where recombination occurs freely. Bryophytes reproduce sexually, but the larger and commonly-seen organisms are haploid and produce gametes; the gametes fuse to form a zygote which develops into a sporangium, which in turn produces haploid spores. The diploid stage is small and short-lived compared to the haploid stage, i.e. haploid dominance. The advantage of diploidy, only exists in the diploid life generation. Bryophytes retain sexual reproduction despite the fact that the haploid stage does not benefit from heterosis; this may be an indication that the sexual reproduction has advantages other than heterosis, such as genetic recombination between members of the species, allowing the expression of a wider range of traits and thus making the population more able to survive environmental variation.
Allogamy is the fertilization of the combination of gametes from two parents the ovum from one individual with the spermatozoa of another. Self-fertilization known as autogamy, occurs in hermaphroditic organisms where the two gametes fused in fertilization come from the same individual, e.g. many vascular plants, some foraminiferans, some ciliates. The term "autogamy" is sometimes substituted for autogamous pollination and describes self-pollination within the same flower, distinguished from geitonogamous pollination, transfer of pollen to a different flower on the same flowering plant, or within a single monoecious Gymnosperm plant. Mitosis and meiosis are types of cell division. Mitosis occurs in somatic cells. Mitosis The resultant number of cells in mitosis is t
Species distribution is the manner in which a biological taxon is spatially arranged. The geographic limits of a particular taxon's distribution is its range represented as shaded areas on a map. Patterns of distribution change depending the scale at which they are viewed, from the arrangement of individuals within a small family unit, to patterns within a population, or the distribution of the entire species as a whole. Species distribution is not to be confused with dispersal, the movement of individuals away from their region of origin or from a population center of high density. In biology, the range of a species is the geographical area within. Within that range, distribution is the general structure of the species population, while dispersion is the variation in its population density. Range is described with the following qualities: Sometimes a distinction is made between a species' natural, indigenous, or native range, where it has originated and lived, the range where a species has more established itself.
Many terms are used to describe the new range, such as non-native, introduced, invasive, or colonized range. Introduced means that a species has been transported by humans across a major geographical barrier. For species found in different regions at different times of year seasons, terms such as summer range and winter range are employed. For species for which only part of their range is used for breeding activity, the terms breeding range and non-breeding range are used. For mobile animals, the term natural range is used, as opposed to areas where it occurs as a vagrant. Geographic or temporal qualifiers are added, such as in British range or pre-1950 range; the typical geographic ranges could be elevational range. Disjunct distribution occurs when two or more areas of the range of a taxon are separated from each other geographically. Distribution patterns may change by season, distribution by humans, in response to the availability of resources, other abiotic and biotic factors. There are three main types of abiotic factors: climatic factors consist of sunlight, humidity and salinity.
An example of the effects of abiotic factors on species distribution can be seen in drier areas, where most individuals of a species will gather around water sources, forming a clumped distribution. Researchers from the Arctic Ocean Diversity project have documented rising numbers of warm-water crustaceans in the seas around Norway's Svalbard Islands. Arcod is part of the Census of Marine Life, a huge 10-year project involving researchers in more than 80 nations that aims to chart the diversity and abundance of life in the oceans. Marine Life has become affected by increasing effects of global warming; this study shows that as the ocean temperatures rise species are beginning to travel into the cold and harsh Arctic waters. The snow crab has extended its range 500 km north. Biotic factors such as predation and competition for resources such as food and mates, can affect how a species is distributed. For example, biotic factors in a quail’s environment would include their prey, competition from other quail, their predators, such as the coyote.
An advantage of a herd, community, or other clumped distribution allows a population to detect predators earlier, at a greater distance, mount an effective defense. Due to limited resources, populations may be evenly distributed to minimize competition, as is found in forests, where competition for sunlight produces an distribution of trees. Humans are one of the largest distributors due to the current trends in globalization and the expanse of the transportation industry. For example, large tankers fill their ballasts with water at one port and empty them in another, causing a wider distribution of aquatic species. On large scales, the pattern of distribution among individuals in a population is clumped. One common example of bird species' ranges are land mass areas bordering water bodies, such as oceans, rivers, or lakes. A second example, some species of bird depend on water a river, etc. or water related forest and live in a river corridor. A separate example of a river corridor would be a river corridor that includes the entire drainage, having the edge of the range delimited by mountains, or higher elevations.
A further example of a bird wildlife corridor would be a mountain range corridor. In the U. S. of North America, the Sierra Nevada range in the west, the Appalachian Mountains in the east are two examples of this habitat, used in summer, winter, by separate species, for different reasons. Bird species in these corridors are connected to a main range for the species or are in an isolated geographic range and be a disjunct range. Birds leaving the area, if they migrate, would leave connected to the main range or have to fly over land not connected to the wildlife corridor. On large scales, the pattern of distribution among individuals in a population is clumped. On small scales, the pattern may be regular, or random. Clumped distribution is the most common type of dispersion found in nat
State Herbarium of South Australia
The State Herbarium of South Australia is located in Adelaide, South Australia. It is Commonwealth herbaria in Australia; the Department of Environment and Natural Resources is the state agency, responsible for the Herbarium, but the Board of the Botanic Gardens and State Herbarium is charged with its establishment and maintenance. In 1954 the State Herbarium of South Australia was founded as part of the Adelaide Botanic Garden; the first flora collection of the state was produced by Richard Schomburgk in 1875. The State Herbarium's collections include collections of Ralph Tate, John McConnell Black, the moss herbarium of Professor David Guthrie Catcheside, the collections of the Field Naturalists Society of South Australia. Since 2000 the Herbarium has been located in the historic Tram Barn A building adjacent to the Adelaide Botanic Garden's Bicentennial Conservatory on Hackney Road, Adelaide. In late 2011 the Herbarium was due to list its one millionth specimen, is producing an on-line version of the Flora of South Australia, 5th edition.
EFloraSA Electronic flora of South Australia Retrieved 18 May 2018