Elminster's Ecologies is a 2nd Edition boxed set containing several 32-page books detailing the ecology of the Forgotten Realms. It is written in-character as Elminster and other characters. In addition to the credited authors, Monte Cook is also credited as a designer.
From the box:
It is this variety of environments that accounts for the variety of life. In my travels I have noted 73 distinct types of pine trees... I estimate the number of fishes at well over five thousand. The number of insect species likely exceeds the number of grains of sand on the shores of Dragon Reach.Every environment, no matter how hostile to humankind, is compatible with some form of life. The diversity and adaptability of organisms are staggering....
- Yielding Tide
- Blackjackal • Derrnog • Elminster
- Cloudlands • Dragon Reach
The box contains several 32-page books:
- Explorer's Manual
- Coastal Aquatic Lands: The Sea of Fallen Stars
- The Cormyrean Marshes
- The Stonelands and the Goblin Marches
- The Thunder Peaks and the Storm Horns
- The Great Gray Land of Thar
- The Settled Lands