Factores que controlan el proceso de paramización en el norte de los Andes (La Rusia, Colombia)

Abstract

The La Rusia moors are located on the western slope of Colombia’s oriental mountain chain in the Boyacá region. (5° 56’ N, 73° 06’ W). The area under investigation is within a height range of 3100-3800 masl and covers an area of 4650 ha. The predominant topography is rugged, in keeping with the alternating geological formations present in the area. The data used to establish the area’s climactic characteristics came from four weather stations located in the region, said data confirms that the region presents a tetraestacional bimodal four-season rain pattern. The type of ecosystem known as “paramo” in the Andean countries, is of special importance in the region for both its role in water regulation as well as its role in the supply of many goods and services; however, its fragility, conditioned by the marked limitations of its physical environment, has resulted in the composition of plant communities being affected significantly by human intervention. The vegetation varies according to the geomorphological features which are typical of the moors, such as moderately steep slopes, escarpments and structural slopes, steep hilly slopes, semi-undulated hillsides and valleys of different types (colluvial, inter-mountainous or u-shaped). The main order of soils found correspond to Andosols. The research supporting this thesis is part of a line of study promoted by the Pedagogical and Technological University of Colombia, which has resulted in publications directed by the author of this thesis; some are of a more technical nature, relevant to resource management and conservation in Colombia: the geology and geomorphology of the La Rusia moors (Valencia et al. 2004), the application of GIS for analysis (Morantes and Reyes, 2006) and climatology (Valencia et al. 2005). A summary of results represents a breakthrough in the scientific understanding of the moorlands as an ecosystem and its dynamics, and has been published in a prestigious international journal about tropical ecosystems (Valencia et al. 2013). A summary on human uses is under review, which describes the changes over the last decades (Valencia et al. 2014). In the development of this doctoral thesis the influence of local factors (human use, soil and climatic conditions) on the changes of vegetation in the latitudes of the moor and sub-moor, obtaining two types of outcomes; the first which was exploratory and descriptive (of a more technical nature of the resources of the region), the second type was carried out with an integrative multivariate statistical synthesis which enabled to address the structural and spatial dynamics between classical altitudinal belts, thereby discussing their more or less stable nature, in accordance with the processes occurring on the boundary and the role which the control factors play within it. For sampling 50 10 × 10 m plots were selected, all of which were from within the altitudinal bands of the altoandino woods, moor and sub-moor and all of which had been subjected to some kind of intervention, such as animal grazing, fire, agriculture and tree felling. It should be noted that said intervention had already ceased prior to the commencement of the research in time frames varying between 5 and 15 years, which allowed to establish and observe a successional dynamic.