Simulating and applying the water retention on organic substrates through a simple linear approach

Abstract This study presents a linear approach that defines the water retention on organic substrates, namely composts and coir. Different substrates are used as sampling material for the experimental data. Results of this experiment show that based on recurring decimal logarithms, from analytical exponential expressions, using only two water retention experimental points, it is possible to define a linear water retention relation for a substrate between − 0.1 kPa and − 10 kPa matric potential values. Due to the low number of parameters involved in this empirical approach a more rapid and accurate determination of substrate water retention. Results indicate that there is a high agreement between the experimental and the prediction values (R2 = 0.953). Moreover, the precision and the simplicity of this method applied to several different organic substrates can contribute to its generalization. Due to its simplicity, it can be easily applied to a high number of cases. As an example, a well-known important application of this approach is on the application of tensiometers.