Near-Infrared Spectroscopy Modelling For Soil Fertility Measurements: A Review

Basic soil composition, or more precisely, soil organic matter, soil clay mineralogy and soil texture have been in the core of most infrared spectroscopy research for soils. Of course, nutrient availability, soil structure, soil microbial activity and soil fertility have also been a major subject of interest over the past two decades. The determination of soil nutrients is now becoming a routine work at large scale to gain high yield. The large number of soil nutrients determining techniques are used. The current paper presented that among tested techniques, Near-infrared reflectance spectroscopy (NIRS) is a best technique which has been used widely with minimum time, low in cost, ecofriendly and rapid determination of chemical, physical properties and organic matter present in soil. Obviously, this useful technique can be used to estimate properties such as mineral composition, SOM, water, percentage of carbon, nitrogen and clay content. It could be used directly in soil mapping, for monitoring soil, for making inferences about its quality and function, and making geomorphological interpretations of its distribution. The development of most accurate and trustworthy NIRS approaches are required.