Question

In examining the decline of the Classic Maya civilization, archaeologists frequently point to the systemic failure of agricultural infrastructure. However, the precise causal mechanisms precipitating this failure are often misunderstood. The prevailing assumption has been that severe, prolonged droughts directly decimated crop yields, starving the population. Yet, paleoclimatic data indicate that while these droughts were severe, they were not unprecedented. The critical catalyst for the agricultural collapse was instead the over-extension of the intricate canal systems used for wetland farming (bajos). Initially, as the population expanded during periods of abundant rainfall, the Maya constructed extensive canals to drain the bajos and increase arable land. When the climate shifted to a prolonged dry period, these heavily modified wetlands lost their natural ability to retain moisture. The canals, originally designed to drain excess water, paradoxically accelerated the desiccation of the soil by channeling scarce groundwater away from the agricultural zones. This rapid loss of soil moisture led to the accumulation of mineral salts on the surface, rendering the land infertile. Consequently, it was not the lack of rainfall alone, but the maladaptation of the existing drainage infrastructure to new climatic conditions that directly caused the catastrophic decline in agricultural productivity.

According to the passage, the acceleration of soil desiccation in the Maya agricultural zones was explicitly caused by which one of the following?