Yes very much so. The soils from the watershed and pond bottom are the source of fertility absent us adding something. The big difference is in how water systems vs. soil systems work and transport nutrients to the plants. In soil you need water (rain) to dissolve the nutrients and act as a transport to plant use while in water the transport is there all the time in copious amounts. The result is nutrients dissolve in water much faster as it is a universal solvent. Some are dissolved , used and leech out much faster than others and if not used in the standing crop of fish , plants , snails , inverts etc they sink to the pond bottom for storage. This can result in excess rooted plant growth or FA problems. Here is some info on the processes. Below is a link to a very good book on line that covers many pond processes from DO to fertility to the entire cycle of pond life.

Pond Fertilization: Ecological Approach and Practical Applications
http://pdacrsp.oregonstate.edu/pubs/fertguide_PDF/fert_guide_TOC.html

Chapter 3. Managing Algal Productivity
http://pdacrsp.oregonstate.edu/pubs/fertguide_PDF/chapter_3_of_fert_guide.pdf