Analysis of Soil/Plant/Water/Air Samples

Prior processing of solid samples, e.g. plant and soil, have to be done by the persons themselves such that samples are already in liquid form for our chemical analysis.

Please contact Dr. Marife D. Corre for arrangement in the priority line for analysis and for the fee to cover consumable costs.

The following analyses can be done in our laboratory:

  • Total extractable N, NH4+, NO3-, phosphate and sulphate from soil extracts (with 0.5 M K2SO4 solution) and water samples, using continuous flow injection colorimetry (SEAL Analytical AA3, SEAL Analytical GmbH, Norderstedt, Germany). Total N is determined by ultraviolet-persulfate digestion followed by hydrazine sulfate reduction (Autoanalyzer Method G-157-96), NH4+ by salicylate and dicloro isocyanuric acid reaction (Autoanalyzer Method G-102-93), and NO3- by cadmium reduction method with NH4Cl buffer (Autoanalyzer Method G-254-02). Phosphate is determined by reaction with molybdate, antimony and ascorbic acid to produce phosphate-molybdenum blue complex (Autoanalyzer Method G-092-93). Sulphate is determined by reaction with barium chloride and methylthymol blue to produce a blue chelate complex (Autoanalyzer Method D-061-92).

    seal
  • Organic C from soil extracts (with 0.5M K2SO4 solution) and water samples, using a Total Organic Carbon Analyzer (TOC-Vwp, Shimadzu Europa GmbH, Duisburg, Germany). Organic C is analyzed by pre-treating the samples with H3PO4 solution (to remove inorganic C) followed by UV-enhanced persulfate oxidation of organic C to CO2 and analyzed by an infrared detector.

    TOC-Vwp
  • Soil exchangeable (using cation exchange method by percolation with 1M NH4Cl solution) elements (e.g. Na, K, Ca, Mg, Fe, Al, Mn), plant and soil total (using pressure digestion in concentrated HNO3) elements (e.g. Na, K, Ca, Mg, Fe, Al, Mn, P, S, Ni, Cu, Pb, etc.) and specific elements (e.g. Fe, Al, P, etc.) from other soil-extraction methods (e.g. ammonium oxalate, pyrophosphate, resin, Bray, sodium bicarbonate) using inductively coupled plasma-atomic emission spectrometer (iCAP 6300 Duo VIEW ICP Spectrometer, Thermo Fischer Scientific GmbH, Dreieich, Germany).

    icp
  • N2O, CO2, CH4, C2H2 and C2H4 concentrations (with gas samples stored in 12-ml glass vials; Exetainer; Labco Limited, Lampeter, United Kingdom) using a gas chromatograph (SRI 8610C, SRI Instruments Europe GmbH, Bad Honnef, Germany) equipped with a flame ionization detector (for CO2 with a methanizer, CH4, C2H2 and C2H4), an electron capture detector (for N2O with a make-up gas of 5%CO2-95%N2 (5.0 purity grade)), and an autosampler.

    GC