Definitions - e

The ecological dimension describes the relationship between people and the environment and the effect that they have on each other in turn.

A major environmental category that surrounds or contacts humans, animals, plants, and other organisms (e.g. surface water, ground water, soil or air) and through which chemicals or pollutants move.

Plants whose leaf cover remains alive year-round, though individual leaves may die and fall. Includes species, such as Rhododendron, whose leaves go dormant and change color at the end of the growing season, then green up again for the new season. Other evergreens, such as Pinus banksiana (Jack Pine), discard batches of leaves periodically. Evergreens may have needles (pine and spruce, for instance) or "broad" leaves (holly and rhododendron). Perennial plants whose leaves all die at once (and usually fall) at the end of each growing season (i.e. maple trees) are deciduous.