Records with abundance of zero incorrectly importing with a value of one

QGIS
#1

Hi,
Thanks for creating such a useful tool.
I am trying to import some ‘absence’ records, but the tool seems to assign an abundance value of one for any imported record that had an abundance value of zero in the CSV file. Is there a way to resolve this?
At the moment I am working around this by changing all 0 values to 999 before importing, so I can change them back within QGIS itself.

Thanks

#2

Hi sagep,

I’ve just taken a look and yes mapped abundance of 0 is indeed being turned into a ‘Richness’ value of 1 which does seem odd.

That said could i ask what you are hoping to output? My first thought, as a work around, is that it might be more useful for you to separate the imports of absence from the presence data (in effect creating 2 layers with the tool). It might make it easier to style and handle in your mapping down the line.

#3

Hi Ben,
Thanks for the work-around idea. That approach would also still require additional data manipulation prior to import that I eventually want to avoid when values import correctly. Keeping both presence and absence data in one set is easier to maintain and reduces layer proliferation. For now I’d rather style the data using style properties manipulation than have to work with 2 layers, but it’s an option for sure.

I’m glad to know that it wasn’t something i was doing incorrectly!
I’d be grateful if someone could post here if / when this gets fixed. Thanks.

#4

Thanks for raising this sagep and for looking into it Ben. I have raised an issue so that when work is next done on the tool, it can be reviewed: Review handling of records with quantity of zero · Issue #51 · FieldStudiesCouncil/QGIS-Biological-Recording-Tools · GitHub

#5

Great, thanks Rich.

Best Wishes
Peter