First in Full Range PDA Spectrometer, Spectroradiometer and Spectrophotometer Systems
Every Spectral Evolution instrument includes DARWin SP Data
Acquisition software with the ability to plot multiple spectra for
Measuring Nitrogen in Soil
 First in Full Range PDA Spectrometer, Spectroradiometer and Spectrophotometer Systems
1 Canal Street  ◊  Unit B1
Lawrence, MA 01840  USA
Tel: 978 687-1833  ◊  Fax: 978 945-0372

Copyright © 2012 Spectral Evolution, Inc
Nitrogen is an important macro-nutrient for plant growth  in soil. The
ability to measure nitrogen in soil can be a key to promote a better
understanding and approach to prescriptive fertilization as part of
precision agriculture.  

Conventional soil chemical measurements are time-consuming and
costly and often result in the destruction of original samples.
Proximal soil  analysis using a field spectrometer or
spectroradiometer like the PSR+ provides a window into the health of
the soil and subsequent health of vegetation growth. By taking in
situ measurements rapidly and without preparing or in any way
affecting the sample, spectral information related to the main
nitrogen absorption features near 1450, 1850, 2250, 2330, and 2430
provide not only indications of nitrogen content but also can be used
to derive quantitative information on total nitrogen using

The PSR+ is a lightweight, reliable high resolution spectroradiometer
designed for field use. The PSR+ covers the full UV/VIS/NIR range
from 350-2500 nanometers with unmatched sensitivity and accuracy.
It is easy for one person in the field to use with an optional handheld
microcomputer and direct screw-on lenses, or fiberoptic connection
to a pistol grip or sample contact probe. The PSR+ includes our
exclusive DARWin SP Data Acquisition software with access to the
USGS spectral library and 19 vegetation indices. It can work in
standalone mode to store up to 1000 field scans before offloading. It
is supplied with two rechargeable lithium-ion batteries each capable
of up to 4 hours of use for a total of 8 hours of scanning. The PSR+ is
also available with a benchtop probe and sample compactor for soil
analysis use in the lab.

Optional EZ-ID sample identification software includes access to
mineral identification libraries — very useful for identifying clays in
soil. Using pattern matching algorithms, EZ-ID matches  your target
scan to known samples and provides a matching “confidence level”
percentage. It also allows you to quickly take scans of known
samples and create your own region-specific library.

Since DARWin saves all your spectra as ASCII files, it can easily be
imported into 3rd party analysis or chemometric programs like TSG,
Cammo’s Unscrambler and R2.

In addition to measuring nitrogen content, other soil analysis
applications can include: topsoil fertility, erosion risk, hydraulic
properties,  soil degradation,  total organic carbon, organic matter in
soil, CEC, and indirect measurement of soil pH.
PSR+  and RS-3500 work with our contact probes for soil
research in the field.