干旱区生态环境知识资源中心

In the present paper we have embarked on the study of the various vegetation belts of the Venezuelan Andes in the State of Merida, using both bloclimatic and vegetation data as a basis for our research. The first step was to divide the area into various transects or belts across the Andes in the Venezuelan range from Lake Maracaibo (75 msl) up to the peaks of the Sierra de la Culata (4,500 msl). In the same way, the range toward the area of the Barinas flats (189 msl) was also divided into transects. Various catenas have been drawn to relate the vegetation of the slopes and peaks with that found in the arid and semiarid inland valleys.

Special emphasis has been placed on relating the altitudinal sequences of vegetation with the data collected from 15 different climate stations located at altitudes from 130 msl to 4,126msl. The climate data from each station has been analyzed in accordance with the model established by Rivas-Martinez (2004), including the hydric data and graphics, which have been coordinated with the vegetation found in each of the belts studied. After classifying the various belts using the criteria set out by Rivas-Martinez loc. cit., we then undertook a comparative analysis of the classifications of the Venezuelan Andes that had previously been carried out by other researchers.

As a result of this study, five thermotypes have been identified for this area: infratropical, thermotropical, mesotropical, supratropical, and orotropical. In addition, four ombrotypes have been established: subhumid, humid, hyperhumid, and semi-arid, with different levels for each type, distributed throughout the different thermotypes. The final result was the identification of 15 different bioclimatic belts for this area.

The results of this study are, we feel, applicable for the management and conservation of this particular terrain.