IEEE P4005

New IEEE Standard - Active - Draft.
The use of soil reflectance spectroscopy is widespread in agriculture, natural environments, mining, soil contamination, urban planning and remote sensing. Soil spectroscopy has been shown to be a reliable, fast, cost-effective, environmentally friendly, non-destructive, reproducible, and repeatable analytical technique that has been increasingly used instead of more expensive soil analysis procedures. It is used in the laboratory, field and remote sensing domains. As the community is still lacking agreed-upon standards or protocols for reliable reflectance measurements in the laboratory and the field, this document is a first step towards an internationally recognized standard. The problem with sharing soil spectral libraries (SSLs) that were acquired using different protocols and conditions is an issue discussed by many researchers. Nowadays, due to the fact that the number of protocols is increasing, variations in laboratory conditions are following suit. Thus, the number of spectrometer types and models is proliferating, directly resulting in significant variations amongst datasets. This makes data-sharing, comparisons, and analyses quite complicated, if not impossible. With a growing spectral community, this issue is becoming prominent as a greater number of users enter this field of science, leading to the direct generation of SSLs at a global scale. There are many influential parameters that impact the spectral response of an individual soil sample, which is even witnessed within the same laboratory utilizing the same protocol. Quantifying the induced systematic uncertainties, to increase the quality of the developed SSLs, is the primary aim of this effort. SSLs are important not only for proximal sensing but also for exploiting all domains of remote sensing. SSLs are becoming a strong dataset for cloud-based online soil analyses as a part of wet chemistry laboratory dynamics. In-order to harmonize measurements between users, instrumentation and protocols, a clear single standard agreed protocol is required. The P4005 standard protocol outlines guidelines for instrumentation checkup, spectra acquisition, calibration, and standardization. It aims to establish common practices and procedures, while facilitating measurement comparability, helping ensure reproducibility across laboratories. The P4005 protocol is the result of detailed discussions (started in 2020) between soil spectral experts that have reviewed the best practices, analysis, and experimented directly with the procedure. As a result, this protocol covers various aspects, including sample preparation, lab and field measurement procedures, quality control, and metadata annotation. Moreover, adherence to P4005 protocol enhances the exchange of soil spectroscopy data, supports meta-data analyses, and facilitates the development of robust predictive models for soil properties. This standard covers the optical region (0.4-2.5µm) and addresses both laboratory and field settings.

This standard defines protocols and schemes for measuring soil spectroscopy in both laboratory and field settings. The standard provides a general standard/protocol for measuring soils using different sensor types and by different users. This standard includes guidelines on sample preparation, measurement environment (sensor checks, sample preparation steps, Quality Assurance (QA) thresholds), and a practical checklist for conducting soil spectroscopy in a consistent and reliable manner. The main objective is to enable users to harmonize measurements from different sources and to guide them in building a standardized soil spectral library.