Historical Perspective on the Tools That Helped Shape Soil Chemistry

Abstract

SSSA 75 th Anniversary Paper T he tools of soil chemistry include instruments, mathematics, models, and software. Th ere is also the mind and imagination. Th roughout the history of our science, we have been shift ing away from a very labor-intensive laboratory environment, where long hours of concentration on tedious tasks was the norm. Th is change in the way we work has been accelerating, particularly since the 1950s. We are accomplishing more work but with less eff ort and more time to contemplate what the data are trying to tell us. Th e essence of our research activity has changed dramatically.Numerous laboratory tools have been used in soil chemistry during the last 200 yr, and the major changes that have occurred are highlighted here. It is hoped that the picture presented will help us decide how to better train our students for the future. By knowing how we have changed in the past and how we appear to be changing in the present, we can perhaps trace the path that we are taking, at least in the near future.Eight major themes are addressed here:1. Th e early years reviews the research environment of the 1800s up to the early 1900s. It marks the beginning years of soil chemistry that shaped many of our ideas for the decades that followed.2. Th e age of electronics covers the early part of the 1900s and the origins of the fi rst portable meters on the market.3. Spectroscopy is at the core of most of our modern methods of analysis. While the development of only a few tools are described here, the impact of spectroscopy on our current research activity cannot be understated.

Optical Chemical Sensor Using Intensity Ratiometric Fluorescence Signals for Fast and Reliable pH Determination

“…S ince the first commercialization of pH meters based on proton selective electrodes nearly a century ago, the potentiometric method has been the superior method of measuring pH. 1 However, the importance of quantification of H + activity is still growing, and in particular, the bioprocessing industry is looking for noninvasive alternatives to the pHelectrode. 2 Optical pH sensors offer such an opportunity as they can be integrated prior to sterilization in single-use equipment.…”

Red/Green Tunable-Emission Carbon Nanodots for Smart Visual Precision pH Sensing

“…pH is one of the most fundamental and widely measured parameters and plays a key role in chemical analyses, environmental monitoring, and biological regulation. − Since Böttger first introduced electrometric methods for determining H + ion concentration, the pH precision problem has been basically solved by routine pH measurements . Nevertheless, with the development of technology, the need for noninvasive and in situ pH tests in biological systems, combined with low-cost and high-precision requirements, i.e., the development of portable rapid pH tests at point-of-care testing (POCT), presents new challenges.…”

“…1−3 Since Boẗtger first introduced electrometric methods for determining H + ion concentration, the pH precision problem has been basically solved by routine pH measurements. 4 Nevertheless, with the development of technology, the need for noninvasive and in situ pH tests in biological systems, combined with low-cost and high-precision requirements, i.e., the development of portable rapid pH tests at point-of-care testing (POCT), presents new challenges. Indeed, the use of conventional pH detection methods is unacceptable in these settings.…”

Fourier-Transform Infrared (FTIR) spectroscopy analysis of seven wisconsin biosolids

“…To better understand the differences among biosolids, we used Fourier-transform infrared (FTIR) spectroscopy to analyze seven biosolids in Wisconsin. FTIR spectrometers collect the entire infrared absorption spectrum of solid compounds at once and then reconstruct it using Fouriertransform mathematics (8). Infrared spectroscopy has been used to analyze organic phosphorus compounds since around 1959 (9).…”