Effects of the intensification in land use on algal biomass and productivity: a simulation of spatial isolation and agrochemical application in experimental freshwater systems

• Grant number: 17/23982-4
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2018
• End date: May 31, 2019
• Field of knowledge: Biological Sciences - Ecology - Applied Ecology
• Principal Investigator: Luis Cesar Schiesari
• Grantee: Bianca Rodrigues Strecht Valente
• Host Institution: Escola de Artes, Ciências e Humanidades (EACH). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 15/18790-3 - Environmental effects of the pasture-sugarcane conversion and pasture intensification, AP.PFPMCG.TEM

Abstract

The conversion of native habitats and subsequent intensification in land use is recognized as one of the main drivers of environmental degradation worldwide. Several lines of evidence now suggest that the loss of biodiversity and ecosystem function in modified landscapes partly result from the spatial isolation and diminishing quality of remaining habitat patches. This Undergraduate Research Project - a component of a PhD Project already funded by FAPESP - proposes to investigate how water body spatial isolation, agrochemical contamination, and their interactions affect the biomass and primary productivity of phytoplankton and periphyton. To achieve this task this project will be based on a field experiment in which artificial ponds distributed at three distances from a source water body will be spontaneously colonized by aquatic and semi-aquatic organisms dispersing, voluntarily or involuntarily, across the terrestrial landscape. Within each distance class we will apply an environmental filter simulating the chemical intensification in land use. The control, simulating ponds in cerrados, will receive no agrochemicals. The treatment simulating ponds in managed pastures will receive weekly applications of inorganic fertilizers. The treatment simulating ponds in plantations will receive, in addition to the weekly applications of inorganic fertilizers, insecticide and herbicide applications according to the typical schedule of agrochemical applications in sugarcane fields in the state of São Paulo. This Project therefore proposes to combine the control of experimental manipulations with the realism of field settings to contribute with the mechanistic understanding of the fate of freshwater ecosystems distributed across tens of millions of hectares of converted landscapes in our country.