Effects of Groundwater Extractions and Agricultural Irrigation Through Spatial Analysis, Endorheic Watershed Case.

Resumen

Objective:

To examine the relationship between human activity and the occurrence of ground fissures in Mennonite agricultural soils within the Laguna de Santiaguillo endorheic watershed.

Design/methodology/approach: Earth fissures were geolocated and digitized using satellite imagery. Remote sensing techniques were utilized to calculate the Normal Difference Moisture Index(NDMI) during the 2023-2024 agricultural cycles. Kernel density per Km2 was calculated by concession and annual concessioned volume. Moreover, the total of rainfall in the study area was calculated using Thiessen polygons to be compared with the monthly NDMI. Results: The study area has groundwater extractions throughout the year to meet the needs of hydric crops, which is observed through annual concession volume with an average density of 6.46 wells/Km². While the NDMI value for the agriculture cycle 2023 presents important variations in specific areas that zones containing major moisture are agricultural production areas, making it evident that the moisture patron is strongly related to agricultural activities in parcels that have a groundwater concession.

Limitations on study/implications: The study area presents significant pressure related to groundwater concessions. According to the Kernel analysis density, it was detected that one of the regions with major volume concessioned density coincides with one of the earth fissures detected through spatial images. These results suggest that this zone presents an advanced subsidence phenomenon. Kernel’s density analysis was calculated based on the volume of CONAGUA’s groundwater concessioned values; it is unknown the exact amount of groundwater extraction from the aquifer.

Findings/conclusions: One of the principal earth fissures coincides with a high Kernel’s density estimation per annual volume concessioned, 30% of the total aquifer’s concessions are in the study area, showing a high concentration of groundwater extractions