Secondary 6 Geography

The biome found between the tropics, hot and wet all year, with the greatest variety of plants and animals on Earth.

A whole formed by the interactions between biotic and abiotic components in an area.

The non-living parts of an ecosystem — climate, soil, water and sunlight — which shape the characteristics of living things.

The living parts of an ecosystem: producers, consumers and decomposers.

The circulation of nutrients among soil, plants and animals; in the rainforest it is extremely fast, with most nutrients stored in plant biomass.

The one-way flow of energy from the sun through producers along food chains to consumers and decomposers, with losses at each level.

A web of interlocking food chains; in species-rich rainforests the food web is especially complex.

The densest layer of the rainforest, where crowns join into a green roof that blocks most sunlight and hosts most species.

The total mass of living organisms in a system; in rainforests most nutrients are stored in biomass rather than soil.

The stable state in which all components of an ecosystem keep their relations in balance; damage to one element can collapse it.

Large-scale clearing of forest through commercial logging, slash-and-burn cultivation and other means — the direct cause of rainforest loss.

Farming that clears and burns forest plots; soil fertility is exhausted within a few years and farmers move on to fresh forest.

The washing away of exposed topsoil once vegetation is removed, degrading land and silting rivers until they flood.

The richness of species in an area; the rainforest leads the world, and felling drives mass extinctions.

A natural system that absorbs and stores carbon dioxide; rainforests are major carbon sinks, and felling weakens them, worsening global warming.

A government-designated protected area restricting development and logging to conserve ecosystems for education and recreation.

An area designated to protect precious species and habitats, with strict limits on human activity.

Tension arising from different stakeholders' goals: indigenous peoples, governments, developers and conservationists each want different things from the forest.

Low-impact tourism centred on observing and learning about nature, giving conservation an income — one compromise between development and protection.

Development that meets present needs without undermining the system's capacity to regenerate or the welfare of future generations.

The atmospheric condition of a place over a short period — temperature, rainfall and wind — changing quickly and widely.

The average weather pattern over a long period, usually thirty years, reflecting a place's long-term atmospheric character.

The sustained rise in global mean temperature, mainly linked to the human strengthening of the greenhouse effect.

The natural warming mechanism by which greenhouse gases absorb longwave radiation from the surface and radiate heat back; human activity has made it excessive.

Gases that absorb longwave radiation, including carbon dioxide, methane, water vapour and chlorofluorocarbons.

High-energy radiation from the sun, most of which passes through the atmosphere to reach the surface.

Low-energy radiation emitted by the warmed surface, absorbed by greenhouse gases and partly radiated back.

Coal, oil and natural gas; burning them releases large amounts of carbon dioxide, the largest human carbon source.

Man-made chemicals once widely used in refrigerants and aerosols; they are greenhouse gases and also damage the ozone layer.

A greenhouse gas that traps heat more strongly than carbon dioxide, mainly from rice paddies, livestock digestion and decomposing waste.

Rising sea levels as seawater expands when warmed and glaciers melt, threatening low-lying islands and coasts.

People forced from their homes by sea level rise, flooding or land degradation — residents of low-lying island nations being the classic case.

Rare and violent weather events — heatwaves, torrential rain, droughts and intense typhoons — growing more frequent with climate change.

The phenomenon of cities being warmer than surrounding countryside because of dense buildings, heat-absorbing concrete, scarce greenery and artificial heat.

Measures targeting the causes of climate change — saving energy, developing renewables and planting trees — to cut greenhouse gas emissions.

Measures targeting the consequences — seawalls, warning systems and drought-tolerant crops — to reduce damage.

Energy from sustainable sources such as solar, wind and hydro, generating power with almost no greenhouse gases — a key mitigation tool.

Net-zero greenhouse gases, with emissions balanced by absorption; Hong Kong has pledged to achieve it before 2050.

The global climate accord adopted in 2015, aiming to hold warming well below 2 degrees Celsius above pre-industrial levels and to pursue 1.5.

The process of nations negotiating how to share emission cuts and costs — difficult because of disputes over historical responsibility and the right to develop.

A locator reading three digits for eastings and three for northings, fixing a position to a tenth of a one-kilometre grid square.

The vertical grid lines on a map, numbered west to east; they are read first in a six-figure grid reference.

The horizontal grid lines on a map, numbered south to north; they are read second in a six-figure grid reference.

The ratio of map distance to real ground distance; 1:20000 means one centimetre on the map equals 200 metres on the ground.

Lines joining points of equal height; close spacing means steep ground, wide spacing gentle ground, and the direction of bulges reveals valleys and spurs.

The vertical interval divided by the horizontal equivalent, written as one in so-many; the larger the ratio, the steeper the slope.

The direction from one point to another measured in degrees clockwise from true north.

The key to map symbols, needed to identify roads, buildings, vegetation and other features.

Section B of Paper 1, testing knowledge and skills at each fieldwork stage such as framing hypotheses, designing surveys and analysing data.

The DSE reporting mode against set standards, with grades 1 to 5 and 5 stars for the best at Level 5.

The format of Paper 1 Section D and Paper 2 Section F, requiring geographic concepts to explain and discuss issues, testing higher-order thinking and value judgement.

The verbs in a question — explain, compare, discuss — dictating the genre and depth the answer must take.

A candidate's clear position on the issue (degree of agreement), stated at the start and held consistently.

The reasons and evidence supporting a stance, tied to geographic concepts and concrete examples.

The higher-order ability to weigh the reliability and importance of opposing arguments before judging — the key to top marks.

Taking and justifying a personal position on the values at stake, such as development versus conservation or fairness versus efficiency.

A revision tool linking concepts and causal relations graphically, weaving unit knowledge into a retrievable network.

Real examples with specific places and mechanisms (such as Amazon felling or Tuvalu's rising seas) that ground an argument.

The official document listing acceptable arguments and mark points, the chief reference for correcting answer structures.

The course's learning mode: starting from questions, collecting and analysing evidence, and building reasoned judgements.