The Loire River system, from headwaters to the estuarine zone, included, has been synthetized recently in a book (F. Moatar and N. Dupont, 2016, La Loire fluviale et estuarienne, Quae, Paris), in which hydrology, water quality, climate change impacts, the river ecology and the migratory fishes are particularly developed.
The Loire River is also presented in Chapter 5 of the 2nd Edition of Rivers of Europe (Elsevier edition, Editors: Klement Tockner Christiane Zarfl Christopher Robinson), the latest update on the Atlantic rivers which drain the western front of Europe.
https://www.elsevier.com/books/rivers-of-europe/tockner/978-0-08-102612-0
Florentina Moatar 