Surface and groundwater relationship in an anthropically modified area.

Area of Science:

• Hydrogeology
• Environmental Science
• Water Resource Management

Background:

• The Adamantina Aquifer is a key water source in Brazil.
• Understanding aquifer recharge and discharge is crucial for water management.
• Land use changes can significantly alter hydrological processes.

Purpose of the Study:

• To assess the relationship between Adamantina Aquifer recharge and Batalha River discharge.
• To investigate the impact of land use on aquifer recharge and river recession curves.
• To evaluate the effectiveness of different hydrological methods for water resource assessment.

Main Methods:

• Utilized Eckhardt Flow Separation Filters, Soil Moisture Accounting Procedure, and modified-Thornthwaite methods for recharge estimation.
• Analyzed hydrological data from 2000-2018 for a 125 km2 basin.
• Integrated multiple methods to understand land-use impacts on aquifer recharge and river behavior.

Main Results:

• Recharge estimates varied by method, ranging from 232.0 mm/yr to 312.6 mm/yr.
• Land use types showed significant control over recharge: sugarcane (193 mm/yr), eucalyptus (150 mm/yr), and urbanization (72 mm/yr).
• Land use impact on recharge exceeded that of topography and soil type.

Conclusions:

• Integrated hydrological methods can effectively assess water availability in data-scarce basins.
• Land-use planning must consider the significant impact of agricultural and urban areas on aquifer recharge.
• The study provides a framework for managing water resources in small Brazilian hydrographic basins.