Santa Monica-based Mahalo, the search and news site run by Jason Calacanis, has cut 10 percent of the firm's staff, Calacanis said in a post on his blog Wednesday. Calacanis said that the moves were due to a "challenging economic environment." According to Calacanis, the firm is "fairly certain" that advertising for the next two years will be "severely depressed." The cuts will give the company runway past 2012. Mahalo is venture backed by Burda Digital Ventures, CBS, News Corp., and Sequoia Capital, and provides human-edited search pages and news summaries.