Technical aspects concerning the detection of animal waste nutrient content via its electrical characteristics

Bioresour Technol. 2013 Mar;132:127-36. doi: 10.1016/j.biortech.2012.12.184. Epub 2013 Jan 11.


The variables influencing corrosion of three metals (galvanised steel, stainless steel, brass) usable for a manure nutrient probe were examined, identifying the best material for field applications. The nutrients in 18 liquid manures were then estimated through the voltage drop between the terminals of a prototype probe. Response Surface Modelling gave the regression functions relating each investigated response only to the statistically-significant factors. After 168h in the manure, it was determined that: stainless steel was the most suitable material for very close electrodes (mass: -1.8% at 15mm), brass can be used with any inter-electrode distance (mass: -13.0% maximum at 35mm). The prototype probe gave reliable estimates (R(2)⩾0.744) of Ntot, Namm, Ptot, Ktot when dry matter and temperature were also accounted for in the regression analysis. Not considering dry matter but just electronically-detectable quantities (temperature, voltage drop), the estimates were only reliable (R(2)⩾0.656) above 20°C.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cattle
  • Copper / chemistry*
  • Corrosion
  • Electric Conductivity
  • Electrochemical Techniques / instrumentation
  • Electrochemical Techniques / methods*
  • Electrodes*
  • Food*
  • Italy
  • Manure / analysis*
  • Regression Analysis
  • Stainless Steel / chemistry*
  • Steel / chemistry*
  • Sus scrofa
  • Zinc / chemistry*


  • Manure
  • Stainless Steel
  • Steel
  • brass
  • Copper
  • Zinc