Structural and non-structural measures for the recovery of tropical streams: effects on aquatic metabolism and macronutrient retention

• Grant number: 17/18519-3
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: April 01, 2018
• End date: July 31, 2021
• Field of knowledge: Engineering - Sanitary Engineering - Environmental Sanitation
• Principal Investigator: Davi Gasparini Fernandes Cunha
• Grantee: Wesley Aparecido Saltarelli
• Host Institution: Escola de Engenharia de São Carlos (EESC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated scholarship(s): 19/17712-0 - Effects of water residence time and light availability on nutrient retention and metabolism: experimental approach on artificial streams, BE.EP.DR

Abstract

The preservation and environmental management of the streams play a key role for the maintenance of biodiversity, besides the guarantee of several direct and indirect benefits offered to the human beings through the ecosystem services. The population growth, associated with shifts in land use and pressures from diverse anthropogenic activities, has been causing the degradation of aquatic environments. The main objective of this research will be evaluating the effect of non-structural and structural measures for the recovery of tropical streams on aquatic metabolism and retention of macronutrients, nitrogen and phosphorus, to subsidize actions to mitigate environmental impacts and maximize the ecoservice of pollution abatement. The activities will be divided into three main stages. In the first, a systematic bibliographic review will be carried out on the main techniques for streams' recovery that are applied worldwide. In the second stage, at least eight streams will be selected, according to the integrity/restoration stage of the canopy cover or to the application of structural recovery techniques. In different hydrological periods (dry, rainy and intermediary seasons), physical, chemical and biological variables of the water will be quantified through in situ measurements with multiparameter probes or laboratory analyzes. The metabolism of the streams will be estimated from the changes in dissolved oxygen concentration in the water, measured by sensors that will be deployed in situ and will record data every ten minutes. The estimation of metabolic rates (gross primary production, respiration and net primary production), and therefore the determination of the prevalence of heterotrophy or autotrophy, will be performed according to the BASE (Bayesian Single-station Estimation) model. The kinetic curves of nutrient retention will be characterized by the TASCC (Tracer Addition for Spiraling Curve Characterization) method. This methodology will allow the quantification of the parameters of the nutrients' cycling and transport in the studied streams, including retention rates and velocities of nitrogen (nitrate and ammonium) and phosphorus (phosphate) forms. Some of these methodologies are not often used in Brazil, which will contribute to the technological advance in the country. In the last stage of the research, experiments will be carried out with direct manipulation/intervention in the streams to simulate the application of structural and non-structural techniques. For example, structures (e.g., barriers or small dams) will be installed to increase the residence time of water in the aquatic system. This will allow the evaluation of how these techniques will affect aquatic metabolism and nutrient retention. Based on the understanding of the effect of these stream recovery techniques on the functioning of aquatic ecosystems, environmental impact mitigation, planning and environmental management actions will be boosted in order to ensure ecosystem services and biodiversity. The results will be published in peer-reviewed international journals and disseminated through presentations in congresses and scientific events. It is also expected that the candidate will be a visiting PhD student in the United States for six months, which will contribute to his professional training and to the internationalization of the postgraduate program. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

FERNANDES CUNHA, DAVI GASPARINI; FINKLER, NICOLAS REINALDO; GOMEZ, NORA; COCHERO, JOAQUIN; DONADELLI, JORGE LUIS; SALTARELLI, WESLEY APARECIDO; CALIJURI, MARIA DO CARMO; POLI MIWA, ADRIANA CRISTINA; TROMBONI, FLAVIA; DODDS, WALTER K.; et al. Agriculture influences ammonium and soluble reactive phosphorus retention in South American headwater streams. ECOHYDROLOGY, v. 13, n. 2, DEC 2019. (16/14176-1, 18/13171-1, 17/50397-5, 17/18519-3)

SALTARELLI, WESLEY APARECIDO; CUNHA, DAVI GASPARINI FERNANDES; FREIXA, ANNA; PERUJO, NURIA; LOPEZ-DOVAL, JULIO C.; ACUNA, VICENC; SABATER, SERGI. Nutrient stream attenuation is altered by the duration and frequency of flow intermittency. ECOHYDROLOGY, SEP 2021. (18/21412-9, 17/18519-3)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

SALTARELLI, Wesley Aparecido. Structural and non-structural techniques for the restoration of tropical streams: effects on aquatic metabolism and nutrient retention. 2021. Doctoral Thesis - Universidade de São Paulo (USP). Escola de Engenharia de São Carlos (EESC/SBD) São Carlos.