How does species diversity differ from ecological diversity?

How does species diversity differ from ecological diversity?

Species diversity refers to the number and distribution of species in an area. It is expressed in terms of ‘number of species per unit area’ and also as number of individuals of different species in an area.
Ecological diversity refers to the diversity at ecosystem level. It is related to different types of ecosystem habitats, e.g. terrestrial (forests, grasslands, etc.) and aquatic (freshwater and marine) ecosystems.