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At the present time 34% of ecosystems in Colombia have been transformed. This phenomenon is specially focused in the Andes and Caribbean regions, and it is largely due to the expansion of agricultural boundaries.

The transformation of ecosystems is a cumulative process that is shaped by human settlements and the use of forest, agricultural, and mining resources.

It is additionally affected by the development of physical infrastructure1, in which ecosystems may be partially or completely replaced by anthropic land covers.

Most studies about transformation processes have been regional or localized and have considered different time periods2-6. In addition, these studies have only focused on deforestation processes partly due to the fact that Colombia is mostly composed of forests and also because other environments, such as savannas and paramos, are usually underestimated in terms of their biodiversity and carbon storage capacities.

Knowledge regarding ecosystem transformation is important in order to assess the impact of human activities on biodiversity, soils, and water. Also, it is a key tool to plan future development in the country. The nation-wide multi-temporal analysis completed by the Universidad Javeriana (Xaverian University) includes the last forty-five years (1970-2014), and, for the first time, differentiates the advance of transformation between the ecosystems of forests, savannas, and paramos. The analysis found that, in 2014, natural land covers have been lost in the percentages of 37.5% in forests, 24.9% in savannas, and 15.9% in paramos.

Since 1970, forest ecosystems diminished in more than 17 million ha mostly due to historic human settlements in forest regions of the Andes, Amazon, and Middle Magdalena Valley. On the other hand, savanna ecosystems presented low levels of replacement by anthropic land covers, despite the fact that they are used for extensive cattle raising. However, the rate of transformation in these ecosystems has increased in the last twenty years, especially in the Orinoquia8, to the point in which more than 15% of savannas have been replaced by introduced grass species and crops. In the Caribbean and Magdalena Valley approximately half of savanna land covers have disappeared to be transformed into crops, and in the Andes of the eastern mountain ridge only a third of the original area survives. All of these remaining areas are currently used for extensive cattle raising systems that could potentially maintain most of the original ecological functions.

Additionally, 15% of all the paramos are estimated to have suffered transformations that have given rise to crops and pastures. Nevertheless, this number does not consider the effect of extensive cattle raising, which is common in many paramo land covers and causes soil compaction that in turn negatively impacts hydrologic levels and associated biodiversity.

Since ecosystems provide numerous ecosystem services to society, improved exploitation and conservation plans may arise from information on the dynamics of ecosystem transformation. Moreover, the present analysis may be used to identify areas of ecosystem transformation and select areas for further detailed analysis.