Some of the models where taken from blendswap.com

http://www.blendswap.com/3D-models/durian/tm_linax_nature_rocks2/			- LinAx
http://www.blendswap.com/3D-models/plants/plant/							- Dracio
http://www.blendswap.com/3D-models/scenes/oasis/							- JoJoJoy
http://www.blendswap.com/3D-models/plants/low-poly-good-quality-palm-trees/	- Blender_noob17

They are all CC_by licenced, you can find more information about the Author at blendswap.com
Many thanks goes to the authors for their great work!