Demography and Population Studies
Demography
Demography is the study of populations, encompassing not only biological aspects but also socio-economic characteristics and their social and labor implications.
Migration
Migration refers to the movement of a population across space. It involves individuals leaving their place of residence. Migration can be internal, occurring within the same country, or external, involving international movements. The consequences of emigration (population departure) include:
- Population loss and even depopulation, particularly when young people leave
- Aging population
- Low birth rate
- Diminished economic activity
Immigration
Immigration is the spatial movement of a population into a new area. The consequences of immigration include:
- Increased birth rate in arrival areas
- Rejuvenation of the population
- Disproportionate growth in immigration areas
- Increased economic activity
- Strain on infrastructure, education, and urban organization
Economy
Economy in this context refers to all economic activities not included in official statistics due to their informal nature. These activities gain importance during periods of economic crisis, allowing the survival of certain population sectors even without recognized worker benefits.
Parish Records
Parish records were used in Spain as demographic sources until the 1970s. However, they are becoming less reliable because not all births and marriages are registered through the church.
Life Expectancy
Life expectancy refers to the average number of years a person is expected to live from birth. Calculating life expectancy is complex because it must consider death risks for different age groups, varying by gender, socio-economic, and socio-professional categories.
Rural Exodus
Rural exodus refers to the Spanish internal migration that occurred as a consequence of the Industrial Revolution. A significant portion of the population moved from rural areas to urban centers, particularly those more developed.
Habitat
Concentrated Habitat
Concentrated habitat refers to a settlement pattern where the population is concentrated in a single nucleus, such as Murcia’s capital city.
Dispersed Habitat
Dispersed habitat occurs when the population is scattered across several cores or individual dwellings, such as in the traditional Andalusian farmhouse (cortijo) and orchard (huerta) landscape.
Population Concepts and Tools
Padrón
The Padrón is a fundamental municipal instrument containing the list of inhabitants in a municipality. As a dynamic document, it is constantly updated, with a major update every 5 years. Its data is public and contains less information than the census. Continuous updates are performed through the permanent record of the population.
Population Pyramid
A population pyramid is a histogram with two axes. The horizontal axis represents the population of men (left) and women (right), expressed in absolute figures or per thousand. The vertical axis represents age groups. A wide base indicates a high birth rate, while a narrow top indicates an aging population. Theoretical models of population pyramids include the Pagoda, Bell, and Bulb shapes.
Population Law
Population law refers to the legal framework governing residents, both present and absent, within a population.
De Facto Population
De facto population refers to the residents physically present in a location at a specific time, including both permanent residents and temporary visitors.
Rural Population
Rural population refers to the population residing in rural areas and primarily engaged in agricultural activities.
Generational Replacement
Generational replacement refers to the average number of children a woman must have to replace the previous generation, typically set at 2.2.
Demographic Cycle
The demographic cycle is a concept that describes the evolution of a population over time, considering its birth rate, mortality rate, and growth rate.
Migration Statistics
Migration statistics are government-compiled data tracking both emigrants and immigrants. These statistics can be unreliable due to the presence of undocumented individuals not officially recorded.
Dependency Index
The dependency index measures the relationship between the child and elderly population compared to the adult population. It is calculated using the following formula: (Child Population + Elderly Population) x 100 / Adult Population.
Urban Concepts
Old Town
The old town is the oldest part of a city, typically corresponding to the pre-industrial city surrounded by walls. It often features a messy layout with a main street where the wall once stood and dense buildings.
Chabolismo
Chabolismo is an urban phenomenon characterized by the presence of slums in peripheral areas of cities, often parallel to communication axes. These areas feature poorly constructed housing occupied by marginalized groups.
Location
Location refers to the topographical position occupied by a city within a landscape, influencing its organization and development.
Radiocentric City
A radiocentric city is characterized by a downtown center from which radial streets depart at right angles, intersected by concentric circles. This layout allows easy access from the periphery to the center, as seen in Vitoria.