AICE Environmental Management - Chapter 4 Vocab

desert: a hostile, barren landscape where less than 250 m of precipitation occurs annually, and biodiversity is low.

tundra: a biome found far north in Asia and Alaska, characterised by long cold, dark winters, and short cool summers. Permanently frozen ground limits vegetation growth to short shrubs and grasses.

grasslands: a biome with grassy plains and few trees, in the tropics and subtropics, typically referred to

*diurnal temperature range: a variation between high and low air temperatures that occur during the same day (e.g. changes between night and daytime temperatures).

*convectional rainfall: rainfall that occurs when the energy of the sun heats up Earth's surface and causes water to evaporate and become water vapour. This then condenses to form clouds at higher altitudes.

*stomata: pores in the leaf or stem of the plant. These form a slit which allows the movement of gases in and out of the spaces between the cells; found mainly on the underside of leaves.

permafrost: areas of permanently frozen ground.

*ecological succession: the process by which the structure of a biological community changes over time.

primary succession: the gradual process by which an ecosystem develops and changes in a region that has not previously been colonised, for example new lava flows.

secondary succession: the gradual process by which an ecosystem develops and changes in a region that has previously been colonised, however, it has been disturbed, damaged or removed.

pioneer species: a hardy species which is capable of being the first to colonize disturbed or newly formed environments.

*primary productivity: the rate at which energy is converted into organic material through photosynthesis by plants (producers).

gross primary productivity: the rate at which producers convert solar energy into biomass. net primary productivity: the rate at which producers convert solar energy into biomass minus the loss of energy through respiration.

ecosystem productivity: the rate of production of biomass for an ecosystem.

native species: a species that originated and developed in specific ecosystem or region and has adapted to living in that area.

invasive species: a species that is able to outcompete other species, causing changes to an ecosystem's balance.

*indigenous: originating or occurring naturally in a specific area; a species that is native to an ecosystem.

*flora: the plants of a particular area, region or environment.

*fauna: the animal life characteristic of an area, region or environment.

*eutrophication; an increase in nutrients in a body of water results in a rapid growth of algae. Algal blooms cover the surface of the water, forming a green layer. When the algae decay and die, a decline in oxygen level occurs, causing significant ecological degradation.

genes: the basic units of heredity (characteristics) passed down from parent to young. For example tall parents are more likely to have tall children as their genes carry that characteristic.

*DNA: the material in cells that carries information about how a living organism will look and function.

Genes make up portion of the DNA.

*evolution: the process by which living organisms have developed and adapted into different forms.

*evolutionary tree: a branching diagram or tree' showing the evolutionary relationships among various biological species based on similarities and differences in their physical and genetic characteristics.

rewilding: restoring an area of land to its natural undisturbed state, specifically through the reintroduction of species of wild animals that have been driven out or hunted to extinction in the area.

*microhabitat: a habitat that is small or limited in extent and that differs from the surrounding habitat.

deforestation: the action of clearing forested areas; the cutting down of trees.

fragmentation: an ecosystem that has been broken up into patches that are too far apart for species to properly interact and reproduce.

*marginal: the trees found along the edges of a forest or cleared area.

*cascading change: a top-down process, where a change made at the top of a food web makes a change throughout the food web and the ecosystem.

*ice shelves: the place where sea ice and ice sheets meet. They are platforms of ice that extend over the edge of the land into the oceans.

*sea ice: the ice that floats on the surface of the oceans and seas.

*geyser: a hot spring in which water boils, periodically sending up tall columns of water and steam.

*hot spring: a source of ground water that is heated by underground volcanic activity.