Análisis de la respuesta fotosintética de la vegetación a las sales y/o sodio del suelo por medio de una imagen hiperespectral en la vereda el salitre del municipio de Paipa-Boyacá

Abstract

Salinization and sodification are physicochemical processes of soil degradation, which affect the photosynthetic response of plants, which is why some countries have used the hyperspectral remote sensing technique to study this problem. For this reason, the main objective of this project was to analyze the photosynthetic response of the vegetation to salts and / or sodium in the soil of the Tunguavita experimental farm, located in the El Salitre village of the municipality of Paipa, Boyacá, using a hyperspectral image. and the physicochemical properties of the soil, corresponding to 46 soil samples taken from previously made pots.

The hyperspectral image was processed and analyzed using ENVI 5.3 and ArcGIS 10.3.1 software, which allowed calculating the NDVI and SAVI vegetation indices, which indicate that most of the vegetation is dense humid, and allowed the calculation of salinity indices. INDSAL and NDSI, which indicate that most of the soil is slightly saline. In addition, a linear correlation was made between the salinity indices and the chemical variables of CE, RAS, PSI and soil pH, with which it was determined that the NDSI presents a greater relationship with the chemical variables of RAS (r = 0, 8) and PSI (r = 0.8).

The ArcGIS software also allowed estimating that 54% of the vegetation is affected by salinity problems in the soil, while 46% of the vegetation is healthy and dense, in a soil free of salinity. The analysis of the hyperspectral image and the chemical properties of the soil, allow to infer that most of the study soil is acid sulphated, for which, strategies were proposed to prevent, mitigate and / or control this problem, such as the application to the soil of calcium silicates and gypsum as amendment, chicken manure as organic fertilizer, mycorrhizae as biofertilizer and plantations of Raigras Lolium perenne, Kikuyo Pennisetum clandestinum, Forage Beet Beta vulgaris and Barley Hordeum vulgare L. study zone.

The development of this study made it possible to make a significant contribution of knowledge in Colombia, and in turn, to promote the study of soil salinity and / or sodicity, through hyperspectral remote sensing, to identify the distribution and spatial concentration of this type of degradation with greater ease and a high level of detail.