Hemeroby index for the assessment of the conservation of pine-oak forests in a micro-watershed

Abstract

The conservation of soil and vegetation is essential to maintain the proper functioning of a watershed, because of the fundamental importance that both components have for the hydrological and ecological processes that occur in it. The term hemerobia represents a measure of the anthropic impact on the flora. Applied to vegetation, the index or degree of hemerobia corresponds to the distance or separation between a current plant community and a potential natural one, or its successional state of climax under the total absence of anthropogenic influence.The conservation status of the pine-oak forest in a micro-watershed of the Gran Sierra Plegada (Great Fold Mountains), in the state of Nuevo León, was assessed by means of a descriptive study and the estimation of the hemeroby index. This index was obtained by comparing the vegetation of interest with the potential natural vegetation; by evaluating specific indicators, it integrates various aspects of the composition, structure and use of the vegetation into a single value. The index assumes that the changes between the two vegetation statuses are the result of human activity, and therefore it indicates the degree of anthropic impact on the vegetation. The studied forest has various degrees of hemeroby. It can be concluded that the conservation status of the micro-watershed area is not optimal.