Banca de QUALIFICAÇÃO: CARLOS ALBERTO NASCIMENTO DA ROCHA JUNIOR

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : CARLOS ALBERTO NASCIMENTO DA ROCHA JUNIOR
DATE: 03/04/2023
TIME: 14:30
LOCAL: Google Meet
TITLE:

SYSTEMIC ANALYSIS OF LAKE ENVIRONMENTS IN THE TROPICAL SEMIARID: SUPPORT FOR EUTROPHICATION
MANAGEMENT AND MITIGATION PROJECTS

KEY WORDS:

Phosphorous dynamic; external loading; Mass balance; Internal loading; Fractionation.

PAGES: 129
BIG AREA: Ciências Biológicas
AREA: Ecologia
SUMMARY:

Eutrophication is considered one of the main water quality problems in lake ecosystems today, leading to losses of important ecosystem goods and services, in addition to economic consequences and a decrease in biodiversity.
Eutrophication is the result of the input of nutrients transported to aquatic ecosystems, which are later deposited in the system. The selection of eutrophication management and mitigation measures requires an adequate
systemic analysis (diagnosis) of each lake. Furthermore, semi-arid aquatic ecosystems are among one of the most vulnerable systems to eutrophication. The general objective of this thesis is to provide information to support projects for the management and mitigation of eutrophic environments in the tropical semi-arid region, through integrated systemic analysis involving water quality, in addition to the analysis of external and internal phosphorus sources and flows. Chapter 1 sought to analyze the dynamics of water quality in a tropical semi-arid reservoir. The results of chapter 1 show the intensification of eutrophicationwith time, mainly due to the reduction of the stored water volume. Furthermore, it shows the dominance of potentially toxin-producing cyanobacteria. The results of chapter 2 show that use and occupation activities, such as agriculture and livestock, increase the amount of mobile phosphorus present in the sediment, which is heterogeneously distributed along the reservoir. These results show that agriculture and livestock are priority activities for proper management. Chapter 3 will seek to analyze the flows of phosphorus charges external and internal to the system through mathematical modeling. With the results of this chapter, we seek to subsidize the estimate of the phosphorus load necessary to mitigate these environments, in addition to highlighting the most important source for the system. In addition, an attempt is made to estimate the phosphorus loads in the dry period and in the wet period, due to the change in the dynamics of phosphorus fluxes between these periods. In chapter 4, it is expected to show the high load of mobile phosphorus in reservoirs of the Brazilian tropical semi-arid region. The study will serve as a basis for obtaining a simplified overview of the internal loads in the Brazilian semi-arid region and will subsidize management actions for these systems. Finally, this thesis represents an important systemic analysis of semi-arid reservoirs, which can serve as a reflection for reservoirs in the world and supports the choice of management measures and the choice of recovery strategies for eutrophic environments.

COMMITTEE MEMBERS:
Externa à Instituição - FABIANA OLIVEIRA DE ARAUJO SILVA
Externo à Instituição - JANDESON BRASIL DIAS
Interna - 1345773 - RENATA DE FÁTIMA PANOSSO
Presidente - 1764855 - VANESSA BECKER