pH
|
Direct measurement in liquid manure
|
1, 2, 3
|
Temperature
|
Direct measurement in liquid manure
|
1, 2, 3
|
Redox potential
|
Direct measurement in liquid manure
|
1, 2, 3
|
Dry matter content
|
Drying of subsamples of 10-g fresh mass at 105 °C overnight in a drying chamber. Quantification by weighting
|
2, 3
|
Microbial activity
|
For testing the microbial activity several suggestions exist. In this case it was mineralisation of 14C-labeled glucose under anaerobic conditions
|
3
|
NH4-N content
|
Ammonium-N, purge and trap-method. Quantification by titration [10]
|
3
|
Nonvolatile N content
|
Analysis of dried manure by determination with element analyser after combustion
|
3
|
Total N content
|
Calculation by addition of NH4–N content and nonvolatile N content
|
3
|
Organic C content
|
Analysis of dried manure by determination with element analyser after combustion
|
3
|
Total P content
|
Extraction of trace elements soluble in aqua regia [11] and phosphor quantification by ICP-OES with a matrix adjusted calibration [12]
|
3
|
Total Cu content
|
Extraction of trace elements soluble in aqua regia [10] and phosphor quantification by ICP-OES with a matrix adjusted calibration [12]. Copper quantification by ICP-OES with a matrix adjusted calibration
|
3
|