Concepts

Deforestation or loss of natural vegetation is defined as the conversion of the original land cover, whether in forest or herbaceous formations, to another type of land cover.

The felling of isolated trees or scattered individuals within a natural area where the rest of the vegetation remains standing is not considered deforestation or a loss of natural vegetation. Consequently, the alerts do not include selective logging, forest management, or understory fires that result in thinning or degradation.

The definition of deforestation and loss of natural vegetation includes several specific characteristics described below:

• Deforestation or loss of natural vegetation: deforestation is commonly associated with the complete removal of forest cover. For the MapBiomas Alerta initiative, this term is also used under a broader concept that includes any loss of natural vegetation, integrating non-forest covers such as paramos and herbaceous formations.
  
• Primary or Secondary Deforestation: primary deforestation refers to the removal of forests or natural vegetation in a primary state. On the other hand, secondary deforestation corresponds to the suppression of vegetation in previously intervened areas that are in a process of regeneration.
  MapBiomas Alerta Colombia primarily addresses primary deforestation, as the alert systems used prioritize these covers. However, secondary deforestation areas with more than 20 years of regeneration, when verified, are also included in the MapBiomas Alerta Colombia data.
  
• Gross and Net Deforestation: gross deforestation refers exclusively to the loss of natural vegetation cover in a given period, without accounting for areas under recovery. On the other hand, net deforestation (or net loss) is the resulting balance from subtracting the area in regeneration or restoration from the total deforested area.
  The MapBiomas Alerta Colombia initiative focuses on the identification and validation of gross deforestation, as its objective is to report every vegetation loss event immediately.
  
• Deforestation Alert and Deforested Area: a deforestation alert refers to a signal or event indicating the possible loss of natural vegetation cover at a specific location. The deforested area, meanwhile, is defined as the land area affected by the removal of natural or primary vegetation.
  MapBiomas Alerta Colombia identifies, validates, and refines these deforested areas using the alerts generated by various available monitoring systems.
  
• Deforestation Detection and Date of Occurrence: the detection date corresponds to the moment when the monitoring system first identifies and confirms a natural vegetation loss event. For its part, the date of occurrence refers to the period during which the alteration or loss of natural vegetation actually took place.
  
• Observed Deforestation Area and Deforestation Rate: the observed area is the spatial extent directly quantified by comparing satellite images (before and after the event). MapBiomas Alerta Colombia reports only the observed area. Deforestation rates are official data generated by IDEAM.
  
• Deforestation Speed: this refers to the ratio between the total deforested area and the time interval between the start and the end of the event. In MapBiomas Alerta Colombia, the speed is determined by an approximate calculation based on the dates of the selected satellite images available to document the before and after of each deforestation event.
  
• Deforestation and Degradation: deforestation refers to the complete removal of natural vegetation, while degradation refers to the deterioration of an ecosystem’s quality, functionality, and productivity, without necessarily involving the complete removal of vegetation cover.