Kerala Plus Two Geography (DHSE) key terms

The number of people living per unit area, usually expressed as persons per square kilometre, obtained by dividing total population by total land area of a region.

The number of people supported per unit of cultivable land, showing pressure of population on agricultural resources rather than on total area.

A model describing the shift of a population from high birth and death rates to low birth and death rates as a society develops economically and socially.

A paired bar graph plotting males and females by age group, used to read a population's age structure, dependency burden and past fertility or mortality trends.

The proportion of people in non-working age groups, children and the elderly, compared with the working-age population, expressed as a ratio or percentage.

Conditions at a place of origin that drive people away, such as unemployment or conflict, and attractions at a destination that draw them in, such as jobs or services.

The permanent or semi-permanent movement of people from one place to another, classified by direction as internal or international and by cause as voluntary or forced.

Money sent by migrants back to their home households, which forms a major source of household income and foreign exchange in many labour-exporting regions.

A composite measure combining life expectancy, mean and expected years of schooling, and per capita income to rank countries by overall human well-being rather than income alone.

The percentage of a population aged seven years and above who can read and write with understanding, a key social indicator of development.

The number of females per thousand males in a population, used to assess gender balance and social conditions affecting women and girls.

The ranking of settlements from hamlet and village through town to city and metropolis, based on population size and the range of services each provides.

A model explaining the size, number and spacing of settlements as service centres, where higher-order centres offer rarer goods and are spaced farther apart.

In service location analysis, the maximum distance consumers will travel for a good and the minimum number of customers needed for a provider to stay viable.

A continuous built-up area comprising a core city and adjoining outgrowths or towns that function as one economically integrated urban unit.

The rising share of a region's population living in towns and cities, accompanied by the physical expansion of built-up land and changes in livelihood.

A large continuous urban region formed when several expanding cities and towns merge physically while retaining separate administrative identities.

Farming in which most produce is consumed by the farmer's household, using small plots, family labour and simple tools, with little surplus for sale.

A form of subsistence farming in which a plot is cleared and cultivated for a few years, then abandoned while the farmer moves to fresh land, allowing natural regeneration.

Large-scale estate farming of a single cash crop such as tea, rubber or coffee, using hired labour, capital inputs and produce destined mainly for export markets.

Farming organised to sell most output, using mechanisation, purchased inputs and larger holdings, often specialising in one crop or livestock product.

A manufacturing activity whose location is not tied to raw material sources because its inputs are light and transportable, so it locates near markets or labour.

The conditions influencing where a factory is sited, including raw material, power, transport, labour, capital, market access and government policy incentives.

A demarcated area within a country where trade, tax and regulatory rules differ from the rest of the economy to attract export-oriented investment and employment.

Highly specialised service work concerned with knowledge generation and decision-making, such as research, consultancy, education and financial analysis.

Economic activity that provides services rather than goods, including transport, trade, banking, education, health care and tourism.

The highest-order service activity involving top-level decision-making and policy formulation in government, corporate leadership and international bodies.

A place where cargo is transferred from one mode of transport to another, such as a port or railhead, often attracting processing industries.

Trade in which goods are imported into a country and re-exported, sometimes after processing or repackaging, without being consumed domestically.

The difference between the value of a country's exports and imports of goods over a period; a surplus occurs when exports exceed imports.

The entire area drained by a river and its tributaries, bounded by divides, within which all precipitation flows to a common outlet.

A ridge or elevated line of land separating two adjacent drainage basins, so that rain falling on either side flows into different river systems.

The catchment area of a stream or river, treated as a unit for soil and water conservation planning and management of land and water resources.

A river system that predates the uplift of the mountains it crosses, so it cuts through the range in deep gorges instead of being diverted.

A seasonal reversal of prevailing wind direction, bringing a wet summer and dry winter to South Asia, driven by differential heating of land and sea.

A low-pressure system travelling from the Mediterranean region that brings winter rain and snow to north-west India, important for rabi crops.

A dry area on the leeward side of a mountain barrier, where descending air has lost its moisture after rising and cooling on the windward slope.

Precipitation caused when moist air is forced to rise over hills or mountains, cooling and condensing to give heavy rain on the windward slopes.

A leached tropical soil formed under heavy rainfall, rich in iron and aluminium oxides, hardening on exposure and poor in nitrogen and organic matter.

Fertile soil deposited by rivers in plains and deltas, consisting of layered sand, silt and clay, and supporting intensive cultivation where irrigation is available.

The removal and transport of topsoil by water or wind, accelerated by vegetation loss and slope, reducing fertility and silting reservoirs.

A large natural region characterised by a distinctive climate and the plant and animal communities adapted to it, such as tropical rainforest or tundra.

A region with exceptionally high numbers of endemic species that has already lost a large share of its original habitat and is a conservation priority.

A plant or animal found naturally in one restricted area and nowhere else, making it especially vulnerable to habitat loss and extinction.

A transition zone between two adjoining ecosystems or biomes, where species from both communities overlap and edge effects are common.

A line on a map joining points of equal elevation above a datum, whose spacing and shape reveal slope steepness and landform features.

A large-scale map showing relief by contours, together with drainage, settlement, transport and land use, used for field and terrain analysis.

The ratio of vertical scale to horizontal scale on a cross-section or profile, showing how many times the relief appears steeper than in reality.

A thematic map in which administrative units are shaded or patterned in graded tones to represent the density or intensity of a mapped variable.

A map on which lines join points of equal value for a continuously varying phenomenon such as rainfall, temperature or population density.

A map in which the size of areas is deliberately distorted in proportion to a statistical value rather than to actual land area.

A straight line or belt laid across a study area along which observations of soil, vegetation, land use or slope are recorded at intervals.

A structured set of written questions administered to selected respondents to collect primary data on household or community characteristics for analysis.

The selection of a representative subset of a population for study, using methods such as random, systematic or stratified selection to draw valid inferences.

A coastal lagoon or brackish water body connected to the sea by a narrow opening, formed by sandbars and fed by rivers and tidal inflow.

A shallow body of water separated from the open sea by a sandbar, spit or reef, often brackish where freshwater inflow mixes with tidal water.