The commercial pilot related that while landing the experimental, amateur built tailwheel airplane at an off-airport, tundra-covered site, the tail started to rise. He said he was unable to keep the tail from rising, and the airplane nosed over, sustaining substantial damage to the right wing and both wing lift struts. The pilot noted that the airplane was exceptionally light, with no significant weight in the rear compartments. He said that the lack of the weight, coupled with a slight tailwind, added to his difficulty in controlling the airplane. He stated that there were no preaccident mechanical problems with the airplane.