Bulgaria DZI Geography flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Map scale

The ratio between distance on a map and the corresponding distance on the ground, expressed as a fraction such as 1:50,000 or as a graphic bar.

Contour interval

The constant vertical distance between adjacent contour lines on a topographic map, chosen to match the relief and the map scale.

Map projection

A systematic method of transferring points from the curved Earth's surface onto a flat plane, always introducing some distortion of shape, area, distance, or direction.

Lithospheric plate

A rigid segment of Earth's outer shell, comprising crust and uppermost mantle, that moves over the asthenosphere and interacts with neighbouring plates.

Mohs hardness scale

A ten-point scale ranking minerals by scratch resistance, from talc at 1 to diamond at 10, used for field identification.

Metamorphic rock

Rock formed when pre-existing igneous or sedimentary rock is altered by heat, pressure, or chemically active fluids without melting, as in marble from limestone.

Subduction zone

A convergent plate boundary where denser oceanic lithosphere descends beneath another plate, generating deep trenches, earthquakes, and volcanic arcs.

Epicentre

The point on Earth's surface directly above the focus of an earthquake, where shaking intensity is generally greatest.

Karst topography

Landscape formed by dissolution of soluble bedrock such as limestone, characterised by sinkholes, caves, disappearing streams, and underground drainage.

Coriolis effect

The apparent deflection of moving air or water caused by Earth's rotation, to the right in the Northern Hemisphere and to the left in the Southern.

Troposphere

The lowest atmospheric layer, where temperature generally decreases with height and where most weather, clouds, and water vapour occur.

Mediterranean climate

A climate type with hot, dry summers and mild, wet winters, typical of western continental margins between roughly 30 and 45 degrees latitude.

Drainage basin

The entire area of land drained by a river and its tributaries, bounded by a watershed that separates it from neighbouring basins.

Aquifer

A body of permeable rock or sediment that stores and transmits groundwater in quantities usable for wells and springs.

Spring tide

A tide of maximum range occurring near new and full moon, when the gravitational pulls of the Sun and Moon align.

Food chain

A sequence of organisms in which each feeds on the previous one, transferring energy from producers through herbivores to carnivores and decomposers.

Biome

A large regional community of plants and animals shaped by climate, such as tundra, taiga, savanna, desert, or tropical rainforest.

Biodiversity hotspot

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

Chernozem

A dark, humus-rich soil of temperate grasslands with high fertility and deep A horizon, typical of the steppe zone.

Soil profile

A vertical section through soil revealing distinct horizons, typically O, A, B, C, and R, differing in colour, texture, and organic content.

Laterite

A deeply leached, iron- and aluminium-rich soil of humid tropical regions, often hard when exposed and poor in available nutrients.

Natural increase

The difference between the birth rate and the death rate of a population over a period, usually expressed per 1,000 inhabitants.

Population pyramid

A graph showing the age and sex structure of a population, with age groups stacked vertically and males and females on opposite sides.

Dependency ratio

The number of people under 15 and over 65 divided by the working-age population, multiplied by 100 to express the burden.

Settlement site

The actual ground a settlement occupies, chosen for advantages such as water supply, flat land, defence, or bridging points.

Urbanisation

The increasing proportion of a population living in towns and cities, usually accompanied by the physical growth of urban areas.

Counter-urbanisation

The movement of people and economic activity from large cities toward smaller towns and rural areas, reversing earlier urban concentration.

Human Development Index

A composite index combining life expectancy, education, and gross national income per capita to rank countries by human development.

Quaternary sector

The part of the economy based on knowledge activities such as research, education, information technology, and consultancy.

Trade balance

The difference between a country's exports and imports of goods and services over a period, giving a surplus or deficit.

Great Rift Valley

A long system of fault troughs running through East Africa and southwestern Asia, formed by crustal extension and associated with volcanoes and lakes.

Stara Planina

The Balkan Mountains crossing central Bulgaria from the Serbian border to the Black Sea at Cape Emine, forming a major east-west divide.