121 ] Besides rainforests, there are over 1,425 km 2 (550 sq mi) of mangroves in Malaysia, [ 108 ] and a large amount of peat forest. At higher altitudes, oaks, chestnuts, and rhododendrons replace dipterocarps. [ 105 ] There are an estimated 8,500 species of vascular plants in Peninsular Malaysia, with another 15,000 in the East. [ 128 ] The forests of East Malaysia are estimated to be the habitat of around 2,000 tree species, and are one of the most biodiverse areas in the world, with 240 different species of trees every hectare. [ 105 ] These forests host many members of the Rafflesia genus, the largest flowers in the world, [ 127 ] with a maximum diameter of 1 m (3 ft 3 in). [ 121 ] Conservation issues Logging, along with cultivation practices has devastated tree cover, causing severe environmental degradation in the country. Over 80 per cent of Sarawak's rainforest has been cleared. [ 105 ] Floods in East Malaysia have been worsened by the loss of trees, and over 60 per cent of the Peninsular's forest have been cleared. [ 121 ] With current rates of deforestation, the forests are predicted to be extinct by 2020. [ 105 ] Deforestation is a major problem for animals, fungi and plants, as the forest is cut to make room for plantations. [ 129 ] Most remaining forest is found inside national parks. [ 121 ] Habitat destruction has proved a threat for marine life. [ 125