Population density is a measurement of population per unit area or unit volume. It is applied to living organisms, most of the time to humans, it is a key geographical term. In simple terms population density refers to the number of people living in an area per kilometer square. Population density is population divided by total land water volume, as appropriate. Low densities may lead to further reduced fertility; this is called the Allee effect after the scientist. Examples of the causes in low population densities include: Increased problems with locating sexual mates Increased inbreeding For humans, population density is the number of people per unit of area quoted per square kilometer or square mile; this may be calculated for a county, country, another territory or the entire world. The world's population is around 7,500,000,000 and Earth's total area is 510,000,000 square kilometers. Therefore, the worldwide human population density is around 7,500,000,000 ÷ 510,000,000 = 14.7 per km2. If only the Earth's land area of 150,000,000 km2 is taken into account human population density is 50 per km2.
This includes all continental and island land area, including Antarctica. If Antarctica is excluded population density rises to over 55 people per km2. However, over half of the Earth's land mass consists of areas inhospitable to human habitation, such as deserts and high mountains, population tends to cluster around seaports and fresh-water sources. Thus, this number by itself does not give any helpful measurement of human population density. Several of the most densely populated territories in the world are city-states and dependencies; these territories have a small area and a high urbanization level, with an economically specialized city population drawing on rural resources outside the area, illustrating the difference between high population density and overpopulation The potential to maintain the agricultural aspects of deserts is limited as there is not enough precipitation to support a sustainable land. The population in these areas are low. Therefore, cities in the Middle East, such as Dubai, have been increasing in population and infrastructure growth at a fast pace.
Cities with high population densities are, by some, considered to be overpopulated, though this will depend on factors like quality of housing and infrastructure and access to resources. Most of the most densely populated cities are in Southeast Asia, though Cairo and Lagos in Africa fall into this category. City population and area are, however dependent on the definition of "urban area" used: densities are invariably higher for the central city area than when suburban settlements and the intervening rural areas are included, as in the areas of agglomeration or metropolitan area, the latter sometimes including neighboring cities. For instance, Milwaukee has a greater population density when just the inner city is measured, the surrounding suburbs excluded. In comparison, based on a world population of seven billion, the world's inhabitants, as a loose crowd taking up ten square feet per person, would occupy a space a little larger than Delaware's land area; the Gaza Strip has a population density of 5,046 pop/km.
Although arithmetic density is the most common way of measuring population density, several other methods have been developed to provide a more accurate measure of population density over a specific area. Arithmetic density: The total number of people / area of land Physiological density: The total population / area of arable land Agricultural density: The total rural population / area of arable land Residential density: The number of people living in an urban area / area of residential land Urban density: The number of people inhabiting an urban area / total area of urban land Ecological optimum: The density of population that can be supported by the natural resources Demography Human geography Idealized population Optimum population Population genetics Population health Population momentum Population pyramid Rural transport problem Small population size Distance sampling List of population concern organizations List of countries by population density List of cities by population density List of city districts by population density List of English districts by population density List of European cities proper by population density List of United States cities by population density List of islands by population density List of U.
S. states by population density List of Australian suburbs by population density Selected Current and Historic City, Ward & Neighborhood Density Duncan Smith / UCL Centre for Advanced Spatial Analysis. "World Population Density". Exploratory map shows data from the Global Human Settlement Layer produced by the European Commission JRC and the CIESIN Columbia University
Soil science is the study of soil as a natural resource on the surface of the Earth including soil formation and mapping. Sometimes terms which refer to branches of soil science, such as pedology and edaphology, are used as if synonymous with soil science; the diversity of names associated with this discipline is related to the various associations concerned. Indeed, agronomists, geologists, physical geographers, biologists, silviculturists, sanitarians and specialists in regional planning, all contribute to further knowledge of soils and the advancement of the soil sciences. Soil scientists have raised concerns about how to preserve soil and arable land in a world with a growing population, possible future water crisis, increasing per capita food consumption, land degradation. Soil occupies the pedosphere, one of Earth's spheres that the geosciences use to organize the Earth conceptually; this is the conceptual perspective of pedology and edaphology, the two main branches of soil science. Pedology is the study of soil in its natural setting.
Edaphology is the study of soil in relation to soil-dependent uses. Both branches apply a combination of soil physics, soil chemistry, soil biology. Due to the numerous interactions between the biosphere and hydrosphere that are hosted within the pedosphere, more integrated, less soil-centric concepts are valuable. Many concepts essential to understanding soil come from individuals not identifiable as soil scientists; this highlights the interdisciplinary nature of soil concepts. Dependence on and curiosity about soil, exploring the diversity and dynamics of this resource continues to yield fresh discoveries and insights. New avenues of soil research are compelled by a need to understand soil in the context of climate change, greenhouse gases, carbon sequestration. Interest in maintaining the planet's biodiversity and in exploring past cultures has stimulated renewed interest in achieving a more refined understanding of soil. Most empirical knowledge of soil in nature comes from soil survey efforts.
Soil survey, or soil mapping, is the process of determining the soil types or other properties of the soil cover over a landscape, mapping them for others to understand and use. It relies on distinguishing the individual influences of the five classic soil forming factors; this effort draws upon geomorphology, physical geography, analysis of vegetation and land-use patterns. Primary data for the soil survey are supported by remote sensing; as of 2006, the World Reference Base for Soil Resources, via its Land & Water Development division, is the pre-eminent soil classification system. It replaces the previous FAO soil classification; the WRB borrows from modern soil classification concepts, including USDA soil taxonomy. The classification is based on soil morphology as an expression pedogenesis. A major difference with USDA soil taxonomy is that soil climate is not part of the system, except insofar as climate influences soil profile characteristics. Many other classification schemes exist, including vernacular systems.
The structure in vernacular systems are either nominal, giving unique names to soils or landscapes, or descriptive, naming soils by their characteristics such as red, fat, or sandy. Soils are distinguished by obvious characteristics, such as physical appearance and accompanying vegetation. A vernacular distinction familiar to many is classifying texture as light. Light soil content and better structure, take less effort to cultivate. Contrary to popular belief, light soils do not weigh less than heavy soils on an air dry basis nor do they have more porosity. Contemporaries Friedrich Albert Fallou, the German founder of modern soil science, Vasily Dokuchaev, the Russian founder of modern soil science, are both credited with being among the first to identify soil as a resource whose distinctness and complexity deserved to be separated conceptually from geology and crop production and treated as a whole; as a founding father of soil science Fallou has primacy in time. Fallou was working on the origins of soil before Dokuchaev was born, however Dokuchaev's work was more extensive and is considered to be the more significant to modern soil theory than Fallou's.
Soil had been considered a product of chemical transformations of rocks, a dead substrate from which plants derive nutritious elements. Soil and bedrock were in fact equated. Dokuchaev considers the soil as a natural body having its own genesis and its own history of development, a body with complex and multiform processes taking place within it; the soil is considered as different from bedrock. The latter becomes soil under the influence of a series of soil-formation factors. According to him, soil should be called the "daily" or outward horizons of rocks regardless of the type. A 1914 encyclopedic definition: "the different forms of earth on the surface of the rocks, formed by the breaking down or weathering of rocks". Serves to illustrate the historic view of soil. Dokuchaev's late 19th century soil concept developed in the 20th century to one of soil as earthy material, altered by living processes. A corollary conc
1890 United States Census
The Eleventh United States Census was taken beginning June 2, 1890. It determined the resident population of the United States to be 62,979,766—an increase of 25.5 percent over the 50,189,209 persons enumerated during the 1880 census. The data was tabulated by machine for the first time; the data reported that the distribution of the population had resulted in the disappearance of the American frontier. Most of the 1890 census materials were destroyed in a 1921 fire and fragments of the US census population schedule exist only for the states of Alabama, Illinois, New Jersey, New York, North Carolina, South Dakota, Texas, the District of Columbia; this was the first census in which a majority of states recorded populations of over one million, as well as the first in which multiple cities – New York as of 1880, Philadelphia – recorded populations of over one million. The census saw Chicago rank as the nation's second-most populous city, a position it would hold until 1990, in which Los Angeles would supplant it.
The 1890 census collected the following information: The 1890 census was the first to be compiled using methods invented by Herman Hollerith and was overseen by Superintendents Robert P. Porter and Carroll D. Wright. Data was entered on a machine readable medium, punched cards, tabulated by machine; the net effect of the many changes from the 1880 census: the larger population, the number of data items to be collected, the Census Bureau headcount, the volume of scheduled publications, the use of Hollerith's electromechanical tabulators, was to reduce the time required to process the census from eight years for the 1880 census to six years for the 1890 census. The total population of 62,947,714, the family, or rough, was announced after only six weeks of processing; the public reaction to this tabulation was disbelief, as it was believed that the "right answer" was at least 75,000,000. The United States census of 1890 showed a total of 248,253 Native Americans living in the United States, down from 400,764 Native Americans identified in the census of 1850.
The 1890 census announced that the frontier region of the United States no longer existed, that the Census Bureau would no longer track the westward migration of the U. S. population. Up to and including the 1880 census, the country had a frontier of settlement. By 1890, isolated bodies of settlement had broken into the unsettled area to the extent that there was hardly a frontier line; this prompted Frederick Jackson Turner to develop his Frontier Thesis. The original data for the 1890 Census is no longer available. All the population schedules were damaged in a fire in the basement of the Commerce Building in Washington, D. C. in 1921. Some 25 % of the materials were presumed another 50 % damaged by smoke and water; the damage to the records led to an outcry for a permanent National Archives. In December 1932, following standard federal record-keeping procedures, the Chief Clerk of the Bureau of the Census sent the Librarian of Congress a list of papers to be destroyed, including the original 1890 census schedules.
The Librarian was asked by the Bureau to identify any records which should be retained for historical purposes, but the Librarian did not accept the census records. Congress authorized destruction of that list of records on February 21, 1933, the surviving original 1890 census records were destroyed by government order by 1934 or 1935; the other censuses for which some information has been lost are the 1810 enumerations. Few sets of microdata from the 1890 census survive, but aggregate data for small areas, together with compatible cartographic boundary files, can be downloaded from the National Historical Geographic Information System. Mayo-Smith, Richmond, "The Eleventh Census of the United States". In: The Economic Journal, Vol. 1, p. 43 - 58 1891 U. S Census Report Contains 1890 Census results Historical US Census data from the U. S. Census Bureau website Hollerith 1890 Census Tabulator by Columbia University "The Fate of the 1890 Population Census" from the National Archives website
A census is the procedure of systematically acquiring and recording information about the members of a given population. The term is used in connection with national population and housing censuses; the United Nations defines the essential features of population and housing censuses as "individual enumeration, universality within a defined territory and defined periodicity", recommends that population censuses be taken at least every 10 years. United Nations recommendations cover census topics to be collected, official definitions and other useful information to co-ordinate international practice; the word is of Latin origin: during the Roman Republic, the census was a list that kept track of all adult males fit for military service. The modern census is essential to international comparisons of any kind of statistics, censuses collect data on many attributes of a population, not just how many people there are. Censuses began as the only method of collecting national demographic data, are now part of a larger system of different surveys.
Although population estimates remain an important function of a census, including the geographic distribution of the population, statistics can be produced about combinations of attributes e.g. education by age and sex in different regions. Current administrative data systems allow for other approaches to enumeration with the same level of detail but raise concerns about privacy and the possibility of biasing estimates. A census can be contrasted with sampling in which information is obtained only from a subset of a population. Modern census data are used for research, business marketing, planning, as a baseline for designing sample surveys by providing a sampling frame such as an address register. Census counts are necessary to adjust samples to be representative of a population by weighting them as is common in opinion polling. Stratification requires knowledge of the relative sizes of different population strata which can be derived from census enumerations. In some countries, the census provides the official counts used to apportion the number of elected representatives to regions.
In many cases, a chosen random sample can provide more accurate information than attempts to get a population census. A census is construed as the opposite of a sample as its intent is to count everyone in a population rather than a fraction. However, population censuses rely on a sampling frame to count the population; this is the only way to be sure that everyone has been included as otherwise those not responding would not be followed up on and individuals could be missed. The fundamental premise of a census is that the population is not known and a new estimate is to be made by the analysis of primary data; the use of a sampling frame is counterintuitive as it suggests that the population size is known. However, a census is used to collect attribute data on the individuals in the nation; this process of sampling marks the difference between historical census, a house to house process or the product of an imperial decree, the modern statistical project. The sampling frame used by census is always an address register.
Thus it is not known how many people there are in each household. Depending on the mode of enumeration, a form is sent to the householder, an enumerator calls, or administrative records for the dwelling are accessed; as a preliminary to the dispatch of forms, census workers will check any address problems on the ground. While it may seem straightforward to use the postal service file for this purpose, this can be out of date and some dwellings may contain a number of independent households. A particular problem is what are termed'communal establishments' which category includes student residences, religious orders, homes for the elderly, people in prisons etc; as these are not enumerated by a single householder, they are treated differently and visited by special teams of census workers to ensure they are classified appropriately. Individuals are counted within households and information is collected about the household structure and the housing. For this reason international documents refer to censuses of housing.
The census response is made by a household, indicating details of individuals resident there. An important aspect of census enumerations is determining which individuals can be counted from which cannot be counted. Broadly, three definitions can be used: de facto residence; this is important to consider individuals who have temporary addresses. Every person should be identified uniquely as resident in one place but where they happen to be on Census Day, their de facto residence, may not be the best place to count them. Where an individual uses services may be more useful and this is at their usual, or de jure, residence. An individual may be represented at a permanent address a family home for students or long term migrants, it is necessary to have a precise definition of residence to decide whether visitors to a country should be included in the population count. This is becoming more important as students travel abroad for education for a period of several years. Other groups causing problems of enumeration are new born babies, people away on holiday, people moving home around census day, people without a fixed address.
People having second homes because of working in another part of the country or retaining a holiday cottage are dif
Race and ethnicity in the United States Census
Race and ethnicity in the United States Census, defined by the federal Office of Management and Budget and the United States Census Bureau, are self-identification data items in which residents choose the race or races with which they most identify, indicate whether or not they are of Hispanic or Latino origin. The racial categories represent a social-political construct for the race or races that respondents consider themselves to be and, "generally reflect a social definition of race recognized in this country." OMB defines the concept of race as outlined for the US Census as not "scientific or anthropological" and takes into account "social and cultural characteristics as well as ancestry", using "appropriate scientific methodologies" that are not "primarily biological or genetic in reference." The race categories include both national-origin groups. Race and ethnicity are considered separate and distinct identities, with Hispanic or Latino origin asked as a separate question. Thus, in addition to their race or races, all respondents are categorized by membership in one of two ethnic categories, which are "Hispanic or Latino" and "Not Hispanic or Latino".
However, the practice of separating "race" and "ethnicity" as different categories has been criticized both by the American Anthropological Association and members of US Commission on Civil Rights. In 1997, OMB issued a Federal Register notice regarding revisions to the standards for the classification of federal data on race and ethnicity. OMB developed race and ethnic standards in order to provide "consistent data on race and ethnicity throughout the Federal Government; the development of the data standards stem in large measure from new responsibilities to enforce civil rights laws." Among the changes, OMB issued the instruction to "mark one or more races" after noting evidence of increasing numbers of interracial children and wanting to capture the diversity in a measurable way and having received requests by people who wanted to be able to acknowledge their or their children's full ancestry rather than identifying with only one group. Prior to this decision, the Census and other government data collections asked people to report only one race.
The OMB states, "many federal programs are put into effect based on the race data obtained from the decennial census. Race data are critical for the basic research behind many policy decisions. States require these data to meet legislative redistricting requirements; the data are needed to monitor compliance with the Voting Rights Act by local jurisdictions". "Data on ethnic groups are important for putting into effect a number of federal statutes. Data on Ethnic Groups are needed by local governments to run programs and meet legislative requirements." The 1790 United States Census was the first census in the history of the United States. The population of the United States was recorded as 3,929,214 as of Census Day, August 2, 1790, as mandated by Article I, Section 2 of the United States Constitution and applicable laws."The law required that every household be visited, that completed census schedules be posted in'two of the most public places within, there to remain for the inspection of all concerned...' and that'the aggregate amount of each description of persons' for every district be transmitted to the president."
This law along with U. S. marshals were responsible for governing the census. One third of the original census data has been lost or destroyed since documentation; the data was lost in 1790–1830 time period and included data from: Connecticut, Maryland, New Hampshire, New York, North Carolina, Rhode Island, South Carolina, Delaware, New Jersey, Virginia. Census data included the name of the head of the family and categorized inhabitants as follows: free white males at least 16 years of age, free white males under 16 years of age, free white females, all other free persons, slaves. Thomas Jefferson the Secretary of State, directed marshals to collect data from all thirteen states, from the Southwest Territory; the census was not conducted in Vermont until 1791, after that state's admission to the Union as the 14th state on March 4 of that year. There was some doubt surrounding the numbers, President George Washington and Thomas Jefferson maintained the population was undercounted; the potential reasons Washington and Jefferson may have thought this could be refusal to participate, poor public transportation and roads, spread out population, restraints of current technology.
No microdata from the 1790 population census is available, but aggregate data for small areas and their compatible cartographic boundary files, can be downloaded from the National Historical Geographic Information System. In 1800 and 1810, the age question regarding free white males was more detailed; the 1820
1930 United States Census
The Fifteenth United States Census, conducted by the Census Bureau one month from April 1, 1930, determined the resident population of the United States to be 122,775,046, an increase of 13.7 percent over the 106,021,537 persons enumerated during the 1920 Census. The 1930 Census collected the following information: address name relationship to head of family home owned or rented if owned, value of home if rented, monthly rent whether owned a radio set whether on a farm sex race age marital status and, if married, age at first marriage school attendance literacy birthplace of person, their parents if foreign born: language spoken at home before coming to the U. S. year of immigration whether naturalized ability to speak English occupation and class of worker whether at work previous day veteran status if Indian: whether of full or mixed blood tribal affiliationFull documentation for the 1930 census, including census forms and enumerator instructions, is available from the Integrated Public Use Microdata Series.
The original census enumeration sheets were microfilmed by the Census Bureau in 1949. The microfilmed census is located on 2,667 rolls of microfilm, available from the National Archives and Records Administration. Several organizations host images of the microfilmed census online, digital indices. Microdata from the 1930 census are available through the Integrated Public Use Microdata Series. Aggregate data for small areas, together with electronic boundary files, can be downloaded from the National Historical Geographic Information System. 1930 Census Questions Hosted at CensusFinder.com 1931 U. S Census Report Contains 1930 Census results Historic US Census data 1930Census.com: 1930 United States Census for Genealogy & Family History Research 1930 Interactive US Census Find stories and more attached to names on the 1930 US census
Jackson County, Michigan
Jackson County is a county located in the U. S. state of Michigan. Its population was 160,248 as of the 2010 Census; the county seat is Jackson. The county was set off in 1829 and organized in 1832, it is named for U. S. President Andrew Jackson and considered to be one of Michigan's "Cabinet counties", named for members of Jackson's Cabinet. Jackson County comprises MI Metropolitan Statistical Area; the Jackson County Courthouse was designed by a prominent southern Michigan architect. Jackson County is home to the Michigan Whitetail Hall of Fame. According to the U. S. Census Bureau, the county has a total area of 723 square miles, of which 702 square miles is land and 22 square miles is water. Grand River- Jackson County and Hillsdale County are the starting point of Michigan's longest river, it starts in Liberty Township in Jackson County. It flows through a small part of Columbia Township, into Summit township, right through the Jackson city limits, it thens flows through Blackman Charter Township and Rives Township and Tompkins Township before entering Ingham County, Eaton County, Clinton County, Ionia County, Kent County, Ottawa County and into the city of Grand Haven where it empties into Lake Michigan.
The river is 260 miles long. Kalamazoo River- the Kalamazoo is made up of the North and South Branches; the North Branch starts in Jackson County in Hanover Township. It starts in Pine Hills Lake and Farewell Lake and flows through a small part of Liberty Township and back into Hanover Township, it flows into Spring Arbor Township and Concord Township. It flows out of Jackson County and into Calhoun County before it goes through the town of Albion where the North Branch connects with the South Branch and they form to be one river; the South Branch starts in the wetlands near the town North Adams in Hillsdale County and flows through the rest of Hillsdale County. It enters Jackson County and goes through a small part of Hanover Township before reentering Hillsdale County and reentering Jackson County where it goes through Pulaski Township, it enters Calhoun County and connects with the Northern Branch when it reaches the town of Albion. When the South Branch and North Branch connect to form just the Kalamazoo River, it flows through the rest of Calhoun County.
It enters Kalamazoo County and Allegan County. When it reaches the towns of Saugatuck and Douglas it enters Lake Michigan. In total the Kalamazoo River is 166 miles long, its watershed drains a total of 2,020 miles and drains into 8 counties. Livingston County Ingham County Eaton County Washtenaw County Calhoun County Lenawee County Hillsdale County The county government operates the county jail, maintains township roads, operates the major local courts, keeps files of deeds and mortgages, maintains vital records, administers public health regulations, participates with the state in the provision of welfare and other social services; the county board of commissioners controls the budget but has only limited authority to make laws or ordinances. In Michigan, most local government functions – police and fire and zoning, tax assessment, street maintenance, etc. – are the responsibility of individual cities and townships. Michigan State House of Representatives, State Representative District 64: Julie Alexander Michigan State House of Representatives, State Representative District 65: Mike Shirkey Michigan State Senate, State Senate District 17: Randy Richardville President pro tempore Michigan State Senate, State Senate District 19: Mike Nofs Prosecuting Attorney: Jerry Jarzynka Sheriff: Steven P.
Rand County Clerk/Register of Deeds: Amanda L. Riska County Treasurer: Karen Coffman Drain Commissioner: Geoffrey W. Snyder County Surveyor: Dean R. Gutekunst As of the census of 2000, there were 158,422 people, 58,168 households, 40,833 families residing in the county; the population density was 224 people per square mile. There were 62,906 housing units at an average density of 89/sq mi; the racial makeup of the county was 88.54% White, 7.92% Black or African American, 0.40% Native American, 0.53% Asian, 0.04% Pacific Islander, 0.83% from other races, 1.74% from two or more races. 2.20 % of the population were Latino of any race. 24.3% were of English, 21.7% of German, 11.5% American, 9.9% Irish and 8.1% Polish ancestry according to the 2012 American Community Survey. 95.9 % spoke 2.1 % Spanish as their first language. There were 58,168 households out of which 33.50% had children under the age of 18 living with them, 53.80% were married couples living together, 12.00% had a female householder with no husband present, 29.80% were non-families.
24.60% of all households were made up of individuals and 9.60% had someone living alone, 65 years of age or older. The average household size was 2.55 and the average family size was 3.03. In the county, the population was spread out with 25.60% under the age of 18, 8.10% from 18 to 24, 30.40% from 25 to 44, 23.00% from 45 to 64, 12.90% who were 65 years of age or older. The median age was 37 years. For every 100 females there were 104.20 males. For every 100 females age 18 and over, there were 103.70 males. The median income for a household in the county was $43,171, the median income for a family was $50,970. Males had a median income of $38,919 versus $26,448 for females; the per capita income for the county was $20,171. About 6.50% of families and 9.00% of the population