Substrate Analysis

The scope of Working Group Substrate Analysis is:

• to further the development and distribution of clear standards for growing media analysis in research and industry,
• to further the acceptance and application of methods in the wider contexts of research and industry.

The wider context being the application of growing media in the production of food and ornamentals, in order to reduce emissions and increase efficiency using circular and renewable materials.

Initiatives of the Working Group are:

• the joint and timely planning of the bi-annual International Symposium on Growing Media, Compost Utilization and Substrate Analysis for Soilless Cultivation for global exchange of thoughts,
• stimulating contact between industry and university research networks, e.g. a young PhD and a research group leader network,
• virtual short-term working groups on relevant topics such as use of irrigation/recirculation, organic fertilizers and micro-organisms,
• access to a (dynamic) glossary of terminology,
• access to a library of public methods and instruction videos,
• access to instruction on minimum standards for experiments and the reporting thereof.

A few current topics are:

• understanding how raw materials like miscanthus, bulrush, willow, bark and wood fiber, change the behavior of growing media. Generally, the water content and stability are lower, pH and nitrogen immobilization are higher, but new or improved methods for characterizing water content, stability, pH (pH buffer) and nitrogen immobilization are needed,
• developing models for predicting the behavior of possible mixes of raw materials. Acceptance of mixing models in practice would benefit from improved methods to predict density increases after mixing materials with differing particle size distributions,
• there is also an interest in more rapid methods, particularly for measuring or predicting water content, nitrogen immobilization and stability of organic matter,
• microbial methods are rapidly evolving but interpretation, application and repeatability in the field still require interdisciplinary attention. An important step could be the simultaneous measurement of relative presence and absolute activity of functional groups. Another step forward could be the cheaper production of species as well as group-specific markers for use in qPCR.