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Topic: Spatial analysis - are all records analysed as points?

Could I ask if someone from NBN can confirm that when using the analysis tools all records are interrogated as point sources? If so I think users should be made aware of this as it has very significant implications on the outputs derived from these queries.

From my very brief exploration I think that when you interrogate records using the analysis tools, 10km records are treated as being a point source in the centre of the 10km square. So, if your search area includes the centre of a 10km square, you get the records for that square, but if it doesn't then these are omitted from the results. And the same would presumably apply to finer scale records too. To me this seems like a significant shortcoming of the analysis tools. Or have I misunderstood?

(I assume this analysis of point data is also why when you view a species account you see such meaningless habitat data as per Andy Musgrove's previous comments regarding Great Northern Diver being shown as a species of improved grassland).

If my above assumptions are correct, can I ask what plans there are to develop the spatial analysis tools to treat records more correctly as polygons? Some progress has been made on displaying records as polygons, but it would be good to know if there are plans to similarly adapt the analysis tools; it would perhaps give some peace of mind to those of us of that are concerned about such things. If we know that the NBN is aware of these shortcomings (and indeed recognise that these are actual shortcomings), and that NBN have future plans to deal with them, that may help to allay fears/misgivings that some users may have about the new system (myself included).

We have often been told that ALS will do so much more than the old gateway - which I'm sure it will. However if it is seen to doing what it does incorrectly or continues to present meaningless and innacurate data (such as misrepresenting species habitat preferences) then it will always be difficult to engender confidence in what the new system does.

My worry (it has been so for some time) is that we have adopted a system which is built around point source data rather than building one that exploits the benefits (and accounts for any disbenefits) of recording using our OS national grid system. I hope in doing so we don't end up spending large amounts of time and money adapting the site to deal with our grid system only to end up with something that doesn't ever quite meet our needs.

MARK

Mark Pollitt
SWSEIC (formerly DGERC)

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Re: Spatial analysis - are all records analysed as points?

Thanks for this Mark - that might indeed make sense re my concerns about the habitat pie-charts (although I'll leave it to the team to answer definitively). Note that Common Lobster also shows a similar propensity for sports fields... ;)

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Re: Spatial analysis - are all records analysed as points?

Hi Mark and Andy,

Thanks for raising this.  We are meeting with the developer to discuss this further and explore including in the project plan.

I will update you further once we have had this discussion

Thanks again
Rachel