Estimation of the CARI Vegetation Index from Spectral Signatures of Stenocereus spp. in Southern Zacatecas

Abstract

The study of spectral variability in cacti is an emerging field with the potential to generate standardized
methodologies for physiological monitoring. This work addresses the lack of protocols for estimating
vegetation indices in Stenocereus queretaroensis, a species of ecological and productive importance in
southern Zacatecas. The objective was to analyze its spectral response over several months to identify indices
capable of distinguishing physiological states and growth stages. Spectral signatures were collected in the
field using a portable spectrophotometer from January to June, evaluating 109 plants within a plot in Jalpa,
Zacatecas, with three segments per individual. As a result, calculations of the CARI vegetation index are
presented, showing differences associated with chlorophyll and carotenoid content, confirming its usefulness
as a reliable indicator. This study provides a methodological foundation for future standardized protocols
applicable to the monitoring of health and productivity in Stenocereus queretaroensis and to the sustainable
management of cacti in arid regions.