This site from MIT (Massachusetts Institute of Technology) features information about the Arctic National Wildlife Refuge, which is an example of the tundra.
The Estuaries Tutorial is an overview of estuarine habitats, the threats facing them, and efforts to monitor and protect estuaries nationwide.
Mission Biomes explores the tundra, shrubland, rainforest, grassland, desert, temperate deciduous forest, and coniferous forest biomes.
This enchanted learning site contains information about a large variety of biomes.
This site contains information about the arctic tundra, deciduous forest, desert, taiga, and tropical forest. Additionally, there is a section about how to read a climograph.
Featuring information on aquatic, desert, forest, grasslands, and tundra biomes.
Recoverability and vulnerability in desert ecosystems. United States Geological Survey