Biologia reprodutiva de Spondias tuberosa Arruda (Anacardiaceae) sob diferentes condições de manejo em uma área de caatinga de Pernambuco

Abstract

Human action under natural environments, such as habitat alteration for the development of agriculture and cattle breeding, is considered one of the major causes of species loss and rupture of ecological processes. Such actions can directly and indirectly affect reproduction aspects of plant species such as blowing, fruiting, dispersion and interaction with pollinators and dispersors. The present work verified the influence of different forms of environment managements in an area of caatinga on the reproduction of Spondias tuberosa Arruda (Anacardiaceae), an andromonoic and endemic species from this ecosystem. In this area distinct soil management conditions were identified, being them characterized by different plant covers, use frequencies and intensities, and where individuals of S. tuberosa were maintained after deforestation. For this work these areas were named as soil management units (MU´s): “serra” and “base da serra” (with regenerating vegetation), “pasto” (pasture)and “cultivo” (mainly maize and bean cultures). Mean floral production, proportion between floral types (hermaphroditic or male), mean fruit production per inflorescence, the composition of pollinators guild and the visitation frequency were investigated in these areas. On average, individuals from the UM “cultivo” produced more flowers per inflorescence than the other UMs. In“serra” and “pasto”, more hermaphroditic flowers were produced in relation to male flowers. Average fruit production was not different among UMs. The only difference in the average number of visits among the UMs was found between “cultivo” (65.83 ± 38.49) and “serra” (11.5 ± 12.8). Cluster analysis concerning number of visits showed that: a) “cultivo” is very far from the other UMs; b) “pasto” and “base da serra” are very close to each other and they are also grouping with “serra” and c) among the visitants, pollinators are the responsible for drawing the differences described above. Visits were made by 19 insect morpho-species, such as bees (31.6%), butterflies (31.65), wasps (26.3%) and flies (10.5%), which mainly collected nectar. Analysis of similarity with pollinators showed a clear separation among the managed and non-managed areas because of their pollinators, suggesting that human action influenced native pollinators behavior, who might have been overlapped by exotic species.