Consequences of the armed conflict, forced human displacement, and land abandonment on forest cover change in Colombia: A multi-scaled analysis

Background/Question/Methods

Most studies of land change have focused on patterns, rates, and drivers of deforestation, but much less is known about the dynamics associated with agricultural abandonment and ecosystem recovery.  Furthermore, most studies are conducted at a single spatial scale, and few have included variables related with internal socio-political conflicts.  Colombia has had a long history of socio-political instability, and thus provides an excellent opportunity to incorporate armed conflict variables in a multivariate analysis of patterns of forest cover change.  The purpose of the present study are twofold: (1) analyzed woody vegetation change (deforestation and reforestation) between 2001 and 2010 for all municipalities at the country, biome, and ecoregion scales; (2) assess the relationship between woody cover change and environmental, demographic, socio-economic, land use, accessibility, and armed conflict variables at multiple scales.  To evaluate the patterns of woody cover change within each municipality, we analyzed the trends performing a linear regression of woody cover area against time (the 10 years of the study-2001 to 2010).  To compare changes in the independent (e.g. environmental, demographic) and dependent (e.g. woody cover change) variables, we used a nonparametric, Random Forest (RF) regression technique. 

Results/Conclusions

Our results illustrate the complexity of forest change, especially when analyzed at multiple spatial scales. First, we determined that environmental variables explained the patterns of deforestation and reforestation at all scales because they can restrict or encourage different land uses across multiple spatial scales.  Second, demographic variables were important at the biome and ecoregion scales as a consequence of the armed conflict, particularly through forced human displacement (e.g. rural-urban migration), which in some areas has resulted in forest regrowth.  Third, armed conflict variables (i.e. paramilitary groups) were the most important variables in some ecoregions, suggesting that their presence can have large impacts on local patterns of forest change.  The direction of their impact depends on: (1) physical properties of the landscape (e.g. lowlands - more deforestation); (2) availability of areas rich in natural and mineral resources to accumulate, generate wealth, and as a source of funding (i.e. Magdalena Medio, Llanos - more deforestation); and (3) the strategic value of the areas for illegal activities (e.g. corridors for transporting weapons and drugs), which favor reforestation.  This analysis provides a new insight into the complex relationship between woody cover change and land abandonment triggered mainly by the armed conflict in Colombia.