Use of Satellite Data to Extract pH Values for Crop Planning and Management of Sorghum and Green Gram in Tharaka Nithi and Machakos Counties, Kenya

Abstract

Soil pH is one of the most important soil properties influencing plant growth and productivity. The pH of the soil affects nutrient availability, microbial activity, and soil structure. As a result, accurate soil pH measurement is critical for effective soil management, plant growth, and sustainable agriculture practices. This study was conducted by analyzing the Landsat 8 satellite images, soil data of field surveys, laboratory analyses and statistical computations. The research combined and integrated the soil data from survey and laboratory with Landsat 8 satellite images to build two multiple regression equations model to enable the comparison of the two datasets i.e., field data and satellite data. The field and satellite data depicted the soil pH to range between 6.4 -7.8 for green gram while that of sorghum study area was 6.5 to 7.5. Field data showed a very strong relationship between field and satellite data with R2 for green gram soil pH being 0.91 while that for sorghum was 0.99. The positive relationship between field and satellite data is an indication that soil pH can be estimated from satellite thereby increasing the frequency of soil pH monitoring and as well as having a cost-effective and rapid method for soil pH determination.