DECIPHERING SPATIAL PATTERNS AND REVEALING TEMPORAL TRENDS IN SOIL MOISTURE FROM ORBITAL REMOTE SENSING DATA: A CASE STUDY IN THE PARANAPANEMA RIVER BASIN

• Grant number: 24/23290-9
• Support Opportunities: Scholarships in Brazil - Master
• Start date: May 01, 2025
• End date: February 28, 2027
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Physical Geography
• Principal Investigator: Rodrigo Lilla Manzione
• Grantee: Maria Angélica Padovani Ederli
• Host Institution: Centro de Estudos Ambientais (CEA). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil

Abstract

Understanding the behavior of the hydrological cycle variables allows water resources management to be based on information about the physical environment in which these variables manifest themselves. The way in which water interacts with watersheds is a determining factor for water conservation in space and time, in a way that human, agricultural and industrial activities can be developed safely and sustainably. Soil moisture is a variable that is difficult to measure and has high spatial and temporal variability, being a determinant control factor for forest fires, agricultural crashes, ecosystem health of fauna and flora, mass movements, landslides and floods. The advent of satellites and remote sensors that measure soil moisture content allows that information about this important component of the hydrological cycle can be included in territorial planning and water resources management. The Paranapanema River Basin (BHRP) plays an important regional role, supporting agricultural, mineral, energy, and tourism activities, as well as several medium-sized municipalities in both São Paulo and Paraná states. In the last decade, the region has suffered from successive water crises mainly due to changes in precipitation patterns, which led to an imbalance in other hydrological cycle variables. Knowing the spatial and temporal patterns of a variable allows us to know not only where it manifests itself with greater or lesser intensity, but also how it occurs over time, which is essential information for monitoring water resources. This project aims to investigate the spatial and temporal variability of soil moisture in the BHRP, using remote sensing data provided by the SMAP (Soil Moisture Active Passive) mission. The research will be conducted using a set of techniques known as Exploratory Spatial and Temporal Data Analysis (ESTDA), aiming to identify spatial patterns of soil moisture distribution, such as clusters of high and low moisture contents, in addition to detecting outliers that may represent anomalies or critical areas from a hydrological point of view. In parallel, temporal trend analyses will be carried out to identify significant variations over time and detect change points in the time series to understand abrupt ruptures in soil moisture behavior. With this, it is expected to map the scale of water planning units (WPUs) as areas most susceptible to extreme weather events, such as prolonged droughts or floods, and provide information to improve water resource management in the region. The study covers the period from 2015 to 2022, allowing an in-depth analysis of the interactions between climate conditions and soil moisture over time. Once hot or cold spots of soil moisture values have been detected over the years, information on agricultural production and wildfires at the municipal scale will be used to verify whether soil moisture has conditioned the occurrence of such episodes during the study period. The results of this study are expected to demonstrate how ESTDA techniques can assist in the planning and management of water resources, deciphering how soil moisture varies in space and revealing whether there is a tendency for soil water to increase or decrease over time. This information can contribute to water and food security in the region, in addition to alerting and preventing water decision-makers and stakeholders about the consequences of climate change on the hydrological cycle at regional level.