Impacto das atividades agropecuárias na biodiversidade no bioma Pampa

Abstract

The Pampas biome is one of the most damaged Brazilian ecosystems and, consequently, most of its area is under a great human impact and its biodiversity is suffering with these activities. This study has the aim to analyze the impact of these anthropic activities on Pampas’ biodiversity, throw a review analysis. For that, the vote counting technique was utilized. This method consists in counting how many times the treatment groups exceeds the control group significantly. In this study, it means how many times in the scientific literature is reported a positive, negative or a null effect of an anthropic activity on Pampas’ biodiversity. The biodiversity indicators were separated in three different levels: toxicological analyzes on biochemical level, abundance analyzes of populations and diversity analyzes on communities. The analysis had nine results at biochemical level, 267 on populations and 16 on communities. The anthropic variables analyzed were (number of times it was studied): arenization (1), forest/ shrub encroachment (11), hunting (1), dogs (1), forestry (1), deforestation (1), edge effect (10), fire (6), agricultural intensification (71) and cattle raising (188). Most of anthropic activities had a very small number of studies related here. Considering that these activities may harm Pampas biome in an irreversible way, it is important to increase the number of studies regarding these activities. Considering the variables most studied, cattle raising had a negative effect in two biochemical studies, 46 populations and one community. This activity also had a null effect on 57 population and a positive effect on 81 populations and in one community. The agricultural intensification had a negative effect on five studies biochemicals, seven populations and six communities. It also had a null effect on 50 populations and a positive effect on three populations. Although both activities had a negative effect on biodiversity in many studies, the proportion of a negative effect was higher for agricultural intensification when compared to cattle raising. Bearing in mind that the cattle raising on Pampas biome is realized in native grasslands, at least in the majority of farms, it will have a smaller negative effect on biodiversity than agricultural intensification, that changes completely the vegetation.