and nine provinces: Kampong Thom , Siem Reap , Battambang , Pursat , Kampong Chhnang , Banteay Meanchey , Krong Pailin , Otdar Meanchey and Preah Vihear . In 1997, it was successfully nominated as a UNESCO Biosphere Reserve . [53] Other key habitats include the dry forest of Mondolkiri and Ratanakiri