How to map distribution based on abundance data

[Justina Akporherhe]

I am a research student doing a research on the Response of Freshwater plankton as bioindicator to water qaulity and climate variability. am comparing data collected from 3 sampling sites of a reservoir for 1986, 2013 and 2017, the data include the plankton (rotifers) , environmental data all in .csv format. My problem is, How do I arrange my data so that it will reflect the abundance of each species for each month and point of collection?. For example, one of the species is A_herrickii which were sampled in the three sampling point in a month, since the sampling points have different abundance, how do I represent this in my species table?. My work is to check if the distribution of these species have been affected over the years in relation to the physicochemical properties of the water body as well as changes in the land use/ land cover. Please I need your assistance. Thank you

[Jamie M. Kass]

First of all, Maxent is usually used with presence data, not abundance data. However, there are some newer applications that can estimate abundance from many presence points, but it seems like you just have 3. You'd need to ignore any count data you have and simply input the coordinates of each observation as a single record to use Maxent.
Second, if you only have 3 data points, any model you make will be bad. You'd need a much better sample that represents an even sampling of the environments the species is found in to make any reasonable model (this goes for any statistical model).
For your data, I don't suggest making an abundance or distribution model. I would suggest something more like an ANOVA, like a comparison of some statistics across the three locations. Else, you need data from more sites.

Jamie

[Justina Akporherhe]

thank you very much for your response