Dados do Trabalho

Título

FLUORESCEIN DIACETATE ACTIVITY AS AN INDICATOR OF DISTURBANCE IN COASTAL DUNES SUBJECTED TO WILDFIRE AND INVASIVE PLANT SPECIES

Resumo

Anthropogenic or natural disturbances alter ecosystems' composition, function, and structure. Microbiological indicators are used to assess soil microbial dynamics, and fluorescein diacetate (FDA) hydrolysis indicates the total activity of soil-decomposing organisms. To evaluate the effect of different disturbances in coastal sand dunes (restinga), we conducted a study in all four seasons of a year in a conservation area in Florianópolis, southern Brazil. The area has a history of disturbances with wildfires and invasion by exotic plants. The study involved four areas with different types of disturbance: wildfire (F), the presence of regenerating individuals of Pinus spp. (P), Pinus spp. + wildfire (PF), and an area with no Pinus nor wildfire (N). Fluorescein diacetate hydrolysis was assessed by extraction with a buffer solution and spectrophotometry. The FDA activity in areas with previous wildfires (PF and F) had higher FDA activity than the P and N areas in all seasons, except for autumn, when the N area had the highest activity. In all seasons, the P site had the lowest FDA activity, 51% and 67% lower than those found in PF in summer and autumn, respectively. Only the P area differed from the other sites in summer, with the lowest FDA activity. The presence of Pinus in the dunes reduces the activity of microorganisms throughout the seasons, highlighting the effects of invasive species on natural environments.

Palavras-chave

Pinus taeda.Pinus ellotti, FDA, soil enzymes, disturbed areas, coastal sandbank.

Instituição financiadora

FAPESC, Capes.

Agradecimentos

Capes, FAPESC, PPGRGV.