Forest Change Detection
Change to a forest may be apparent only after long periods of time, a result of many almost imperceptible and yet powerful forces. Many forests are slow-growing and relatively long-lived. Forests can give the impression of stasis, climax, an almost unchanging timeless character. But change is a defining characteristic of forests, in landscape pattern and function, occurring at virtually all spatial and temporal scales. An example might be the creation of a soil horizon layer in a conifer forest, predictable by considering the climate conditions, litterfall, and microbial activity. Successional changes, growth changes, changes as a result of structural and age processes, all accrue slowly and with generally small daily, weekly, monthly, even annual variability. Change can also be rapid and transformative; for example, leaves can change color and cell structure overnight. Powerful, even cataclysmic, forces can arrive with little or no warning. Examples might include a wildfire, an insect outbreak, a windthrow, a harvesting operation, or a prescribed burn.