Diatoms comprise 40-60% of the world’s primary production and provide the basis of aquatic food chains. They are the basis of our organic carbon an silica cycles and because of their deposits worldwide, diatoms are the source of the fossil fuel deposits that we use. Diatoms are also used widely as bioindicators of the environment because they occur in conditions specific to particular physical and chemical conditions and are found in particular habitats or on particular substrates. The Environmental Protection Agency published a report in 1974 by Rex Lowe entitled, “Environmental Requirements and Pollution Tolerance of Freshwater Diatoms” (https://nepis.epa.gov/Exe/ZyNET.exe/2000JIHM.TXT?ZyActionD=ZyDocument&Client=EPA&Index=Prior+to+1976&Docs=&Query=&Time=&EndTime=&SearchMethod=1&TocRestrict=n&Toc=&TocEntry=&QField=&QFieldYear=&QFieldMonth=&QFieldDay=&IntQFieldOp=0&ExtQFieldOp=0&XmlQuery=&File=D%3A%5Czyfiles%5CIndex%20Data%5C70thru75%5CTxt%5C00000001%5C2000JIHM.txt&User=ANONYMOUS&Password=anonymous&SortMethod=h%7C-&MaximumDocuments=1&FuzzyDegree=0&ImageQuality=r75g8/r75g8/x150y150g16/i425&Display=hpfr&DefSeekPage=x&SearchBack=ZyActionL&Back=ZyActionS&BackDesc=Results%20page&MaximumPages=1&ZyEntry=1&SeekPage=x&ZyPURL). It is used widely, and since then, others have published data on diatom species and their tolerances to particular environmental conditions, but these findings are scattered in disparate sources. Having all of the data in one publication would be a tremendous accomplishment and be of the utmost utility to scientists, policy makers, and the public. Having up to date information is also of the greatest importance especially regarding the study of the connection between environmental conditions and climate change.
This is where Foldscope users might be able to provide an important contribution to bioindicator studies. We as a community could develop a database of diatoms documenting the particular environments where they are found. I am always eager to see diatoms and would do my best to aid in identifications. Various slide mounting techniques would need to be used (see: https://microcosmos.foldscope.com/wp-content/uploads/JLP-10K-Foldscope-Project-Oct-2015.pdf, pages 29-30) to enable the clearest possible view of the diatoms. What do you think? Is this something Foldscope users would like to do?