Soil Solution Sampling Equipment

November 10, 2010

Soil Solution Sampling is the technique whereby the liquid which resides in the soil pores is extracted under suction. Traditionally the solution was collected through a porous ceramic cup into a collection cane. These cups are cheap but the sample can react with the ceramic and alter the chemical characteristics of the sample. Nonetheless they still have a role to play in extraction of those parameters such as Nitrates which are unaffected by the cup’s construction material. More recently other porous materials such a Teflon/quartz, nylon, glass and polymers have been used.

An internet search will reveal a large amount of information on soil solution sampling techniques and there are proponents of each and every porous material.

In our extensive experience of over 25 years in environmental research we have seen fashions and opinions change and each year there is one material which is ‘flavour of the month’ and the following year some researcher will point to its unsuitability. We have stopped ‘following fashion’ and after much research and consideration decided to recommend just two types which have stood the test of time: Ceramic Cups and Rhizon samplers which use an inert porous polymer.

Both these soil solution sampling methods have common parts: a porous cup, a tube and a connection to put the system under negative pressure. In our experience of supplying many of the leading environmental consultancies, academic institutions and agricultural researchers – with the best soil sampling equipment that’s available – it is the material of the porous cup which determines the quality and quantity of the sample.