Rhizon pore water sampling

Previous applications of rhizons produced pore-water analyses which were very similar to those of compressed pore-water samples, except for the phosphate concentrations which were significantly higher when rhizons were used. This agrees with the observations made by Jahnke et... 

Samples collected with these devices may inadequately represent the pore water in its natural occurrence because of problems inherent in the technique (Litaor, 1988). This limitation may be additionally influenced by the complex nature of the soil, whose heterogeneity highly affects the chemical concentrations in pore water. Hence, Rhizon samplers, with their small cross-sectional area, may not adequately integrate for spatial variability (Amoozegar-Fard et al., 1982 England, 1974 Haines et al., 1982), and may represent point samples with qualitative rather than quantitative attributes (Biggar and Nielsen, 1976). 

Rhizons are manufactured and distributed by Rhizosphere Research Products (Dolderstraat 62, NL-6706 JG Wageningen, The Netherlands) or Eijkelkamp (PO. Box 4, NL-6987 ZG Giesbeek, The Netherlands). Their price is markedly higher as compared to filters used for pressing pore water out of a sediment sample, however, they can be used more than just once. Special sizes and connectors will be supplied, if a larger number of pieces is ordered. 

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