Do nutrients leak from pots that are irrigated from below (capillary irrigation)?

Background

Capillary mat irrigation is used in the nursery industry and as a teaching/research tool in SAFS.  While water moves upwards, there is potential due to gravity and diffusion for water to move downwards and out of the pot (leachate). The characteristics of this leakage is unknown.

Objectives

To measure nutrient content of leachate and its interaction with irrigation type (open and closed), media type (sand and coir), and plant species (sunflower, sorghum, no plant).
Activities: You will become familiar with pot watering systems, contribute to project detail, set up capillary mat and a closed irrigation system, prepare pots, germinate seeds and plant and look after their irrigation needs, collect weekly water samples, run an auto-analyser in the measurement of solution nitrogen.

Deliverables

Establishing which nutrients are leached, their relative quantities and comparison with soil solution concentrations in the pot, how these attributes are influenced by irrigation type, media type and plant species. An introduction to relevant model development on potential leakage.