There are a number of conservation areas in the district's mountains and wetlands, in particular the world-famous Shennongjia National Nature Reserve (神农架国家自然保护区), listed on UNESCO's World Network of Biosphere Reserves.[2] The reserve includes 2,618 square kilometres (1,011 sq mi) of forest,[3] and, due to a variety of natural conditions at different elevations, has high plant diversity. One survey by Chinese botanists reports 3,479 higher plant species found in a certain area.[4]