The modern Forel-Ule scale: a `do-it-yourself' colour comparator for water monitoring

Spectral analysis of the Forel-Ule ocean colour comparator scale

François Alphonse Forel (1890) and Willi Ule (1892) composed a colour comparator scale, with tints varying from indigo-blue to cola brown, to quantify the colour of natural waters, like seas, lakes and rivers. For each measurement, the observer compares the colour of the water above a submersed white disc (Secchi disc) with a hand-held scale of pre-defined colours. The scale can be well reprodu...

JASs Do it yourself

JASs Do it yourself

This paper provides detailed description of a non-destructive, low-cost, and low-time consuming technique for producing high-resolution casts for the observation of taphonomic modifications on bone surfaces. The aim of the whole process is to obtain molds that accurately replicate the original bone surface at both the macroand microscopic levels. The high quality transparent epoxy casts produce...

Classifying Natural Waters with the Forel-Ule Colour Index System: Results, Applications, Correlations and Crowdsourcing

Societal awareness of changes in the environment and climate has grown rapidly, and there is a need to engage citizens in gathering relevant scientific information to monitor environmental changes due to recognition that citizens are a potential source of critical information. The apparent colour of natural waters is one aspect of our aquatic environment that is easy to detect and an essential ...

do it yourself

It can take ages to meet the right partner. So much so that plants lost their patience millions of years ago and thought up something else: the art of selfing. Many flowering plants are indeed capable of extensive in-breeding – by way of a rather subtle form of hermaphroditism – to ensure their spread and survival. The common mouse-ear cress, Arabidopsis thaliana, which has become the model pla...