Understanding patterns within a community is easy when the community has a relatively low number of species. However most communities do not have a low number of species.[4] Measuring species abundance allows for understanding of how species are distributed within an ecosystem.[4] For example, salt water marshes have an influx of sea water, causing only a few species which are adapted to be able to survive in both salt and fresh water to be abundant. Inversely in land locked wetlands, the species abundance is more evenly distributed among the species who live within the wetland.[4]