There are many ways to present and analyse sap flow data. There is no standard approach, statistical test or graphics which is applicable to all studies and applications. Rather, the approach taken depends on the hypotheses being tested.
To make life easier for scientists and researchers, scientists at ICT International have collated numerous presentation and analytical techniques which have been published in sap flow studies all in the one document:
Although this list is not exhaustive; it does the provide a comprehensive reference for anyone interested in analysing sap flow data. The document provides hints on how to present summary and representative data as well as tabular data. The document also provides numerous statistical techniques and how to actually perform them. Simple statistics, such as linear regression and ANOVA, to complex statistics, such as partial regression and generalised additive models, are discussed in a simple and easy to use format.
We definitely recognise that there a numerous other approaches which can be taken to analysing sap flow data. Please leave your comments or recommendations to this post.
An example data analysis technique from Duursma et al (2011). This figure shows the response of transpiration (sap flow) against vapour pressure deficit (VPD) for a water x CO2 experiment.