Sequential Gaussian simulation for mapping the spatial variability of saturated soil hydraulic conductivity at watershed scale.

Autor: dos Santos, Rodrigo César de Vasconcelos, Siqueira, Tirzah Moreira, Soares, Mauricio Fornalski, Nunes, Rômulo Félix, Timm, Luís Carlos
Zdroj: Applied Geomatics; Sep2024, Vol. 16 Issue 3, p719-730, 12p
Abstrakt: The saturated soil hydraulic conductivity (Ksat) exhibits high spatial variability due to the various physical, chemical, and biological processes that act simultaneously with different intensities in soil formation. The use of geostatistics as a tool to study soil heterogeneity facilitates the understanding of the spatial variability of Ksat. This study aimed to simulate the spatial variability of Ksat and evaluate its uncertainties using sequential Gaussian simulation (SSG) in a tropical watershed located in southern Brazil. Soil sampling was conducted in an experimental watershed-scale grid with a sample spacing of 300 m, and Ksat was analyzed. Descriptive statistics were applied to assess the behavior of Ksat spatial variability, followed by geostatistical analysis, specifically SSG. Variogram parameters were defined, and SSG was used to generate 100 equiprobable random fields. The results showed that Ksat in the Santa Rita watershed (SRW) is heterogeneous, and uncertainties among the hundred fields ranged from 58.70 to 81.10 mm h-1 for the 5th and 95th percentiles, respectively, possibly influenced by soil type, land use, density, and texture. The criteria for validating SSG simulation were met and successfully described the spatial continuity of Ksat in the SRW. Thus, SSG proved to be an effective tool for understanding the magnitude and structure of Ksat spatial variability at the watershed scale, contributing to effective soil and water management in the SRW. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index