projection on country with no species occurrence
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Wannes Dermauw
Jun 15, 2021, 7:03:51 AM6/15/21
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Hi
I used MaxEnt to do species distribution modeling for Belgium.
Importantly, the species does not (yet) occur in Belgium.
In MaxEnt, I use the WORLDCLIM variables of Belgium in the "projection layer directory file" , while in "envirommental layers" I used the WORLDCLIM variables of
A) only the region where the species is occurring (Middle East + INdia)
or
B) the region where the species is occuring + not occuring (Middle East + India+ Europe)
Using the same settings in MaxEnt the prediction for Belgium (projection layer) is however very different between A and B (see attachments), with prediction for B being more realistic/fitting expectations. Is this a known issue or maybe I did not use the correct settings/approach?
Any advice is more than welcome.
Regards
Wannes
Bede-Fazekas Ákos
Jun 15, 2021, 7:44:58 AM6/15/21
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Hi Wannes,
all species distribution models assume that the distribution of the species is in equilibrium with the environment. We know that this is not true in several cases (e.g. invader species)... Anyway, by defining the extent of the training region (i.e. whether you include or exclude Europe) you make a decision about the region of equilibrium. So if you think that the species could not yet invaded Europe (due to e.g. barriers or lack of time) but this continent is within the fundamental niche, then option A is correct. If you think that Europe falls outside the realized niche because it is also outside the fundamental niche, then option B is correct. The decision is nothing to do with modeling or MaxEnt. It should be decided based on the ecology and biogeography of the species.
HTH,
Ákos
all species distribution models assume that the distribution of the species is in equilibrium with the environment. We know that this is not true in several cases (e.g. invader species)... Anyway, by defining the extent of the training region (i.e. whether you include or exclude Europe) you make a decision about the region of equilibrium. So if you think that the species could not yet invaded Europe (due to e.g. barriers or lack of time) but this continent is within the fundamental niche, then option A is correct. If you think that Europe falls outside the realized niche because it is also outside the fundamental niche, then option B is correct. The decision is nothing to do with modeling or MaxEnt. It should be decided based on the ecology and biogeography of the species.
HTH,
Ákos
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Wannes Dermauw
Jun 15, 2021, 8:59:43 AM6/15/21
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Dear Akos
Thank you for your reply.
However, I am a bit confused, could it be that you switched options?
Europe is within fundamental niche -> include Europe in Environmental layers (option B)
Europe is not wihtin fundamental niche -> exclude Europe in Environmental layers (option A)
Also, how you determine the "fundamental niche", are there any guidelines for determining the limits of "fundamental niche"?. FYI, the species is an insect feeding on fruit of fruit trees.
Regards
Wannes
Op dinsdag 15 juni 2021 om 13:44:58 UTC+2 schreef Ákos Bede-Fazekas:
Bede-Fazekas Ákos
Jun 15, 2021, 9:17:18 AM6/15/21
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Dear Wannes,
No, it is not switched. You should decide whether the (pseudo)absence of the species from Europe is caused by environmental reasons (equilibrium, option B) or by non-environmental reasons (Europe is not in the equilibrium region, option A).
how you determine the "fundamental niche": literature, expert decision, field experiment
HTH,
Ákos
No, it is not switched. You should decide whether the (pseudo)absence of the species from Europe is caused by environmental reasons (equilibrium, option B) or by non-environmental reasons (Europe is not in the equilibrium region, option A).
how you determine the "fundamental niche": literature, expert decision, field experiment
HTH,
Ákos
To view this discussion on the web visit https://groups.google.com/d/msgid/maxent/0036161c-da70-40c9-9f02-8b83adbf1baan%40googlegroups.com.
Wannes Dermauw
Jun 17, 2021, 6:59:56 AM6/17/21
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Dear Akos
Thank you for being clear.
Just wondering, is your MaxEnt suggestion/advice published somewhere, so I can refer to it in M&M?
Kind regards
Wannes
Op dinsdag 15 juni 2021 om 15:17:18 UTC+2 schreef Ákos Bede-Fazekas:
Bede-Fazekas Ákos
Jun 17, 2021, 7:05:43 AM6/17/21
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Dear Wannes,
I'm sure it is published in several papers, but I can't direct you to one of them.
Have a nice day,
Ákos
I'm sure it is published in several papers, but I can't direct you to one of them.
Have a nice day,
Ákos
To view this discussion on the web visit https://groups.google.com/d/msgid/maxent/31fb3b34-5e20-4a9d-badb-adaa642c8956n%40googlegroups.com.
Wannes Dermauw
Apr 21, 2022, 11:53:31 AM4/21/22
to Maxent
Hi
Also, could one use climate type occurrence for deciding whether a given region belongs to the fundamental niche of a species?
Kind regards
Wannes
Op donderdag 17 juni 2021 om 13:05:43 UTC+2 schreef Ákos Bede-Fazekas:
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