The influence of extreme hydrological events on floristic diversity in agroforestry backyards

Abstract

Riverine communities in Amazonian floodplains are increasingly vulnerable, due to high variations in river levels, frequency of intensity of extreme hydrological events. Among traditional land use systems, agroforestry orchards are considered as means that guarantee, besides the conservation of agrobiodiversity, through the food produced for own consumption and the generation of income. The objective of this work was to understand the relation of extreme hydrological events with the decrease of in floristic diversity in the Terra Nova District, Careiro da Várzea municipality, Amazonas state, Brazil, from a case study involving the analysis of the floodplain environments in two riverside communities. The methodological strategies involved quantitative and qualitative tools in the analysis of interviews, forms, and inventories of every orchard studied. Results indicate that large floods influence the livelihoods of the riverine population concerns the mens, of production and income obtained from the orchards, by means of an abnormal mortality of established arboreal individuals, namely, fruit trees. Nature has responded to these events in such a way that the inhabitants of this district have come to perceive the ongoing changes in terms of fruit tree mortality. With the collaboration of the settlers, floristic inventories in communities, it was possible to identify that the mango (Mangifera indica) and coconut (Cocos nucifera), the species most frequent in agroforestry plantations and of greater socioeconomic importance for the populations, are among those suffering the highest mortality during the floods that have been occurring since 2009. It is evident that extreme hydrological events contribute to the decrease of the floristic diversity by means of the deaths of fruit trees in agroforestry orchards of the studied in the riverine communities studied.