I have a dataset which contains monthly sampled zooplankton data. It is always for the same sampling site so not spatial, but over 10 years. I wanted to use an NMDS plot to see if the zooplankton community (during MArch, April and May) from 2014-2024 would be grouped into distinct communities using an NMDS but it comes out arch shaped. Can I solve this? The samples do not have extra environmental variables. I used the total abundance (m-3) of each sample.