The East African montane forests is a montane tropical moist forest ecoregion of eastern Africa. The ecoregion comprises several separate areas above 2000 meters in the mountains of South Sudan, Uganda, Kenya, and Tanzania.
Geography
The East African montane forests extend across a total of , in 25 separate enclaves, which range in size from 23,700 to 113 square kilometers. The montane forests extend down to approximately 1000 meters elevation, and as high as 3500 meters. The northernmost enclave is on Mount Kinyeti in the Imatong Mountains of South Sudan, extending south through Mount Moroto in eastern Uganda and Mount Elgon on the Kenya-Uganda border. In Kenya and Tanzania, the ecoregion follows the mountains east and west of the Eastern Rift and associated volcanoes, including the Aberdare Range, Mount Kenya, Mount Kulal, Mount Nyiru, Bukkol, and the Nguruman Escarpment in Kenya, and Mount Kilimanjaro, Mount Meru, Ngorongoro, and the Marang forests (Mbulu Highlands and Mount Hanang) in northern Tanzania.
Climate
The climate of the ecoregion is more temperate and seasonal than the surrounding lowlands. Temperatures can fall below 10 °C (50 °F) in the coldest months (July and August) and rise above 30 °C (86 °F) in the warm season. Temperatures are generally lower at higher elevations, and frosts can occur at the highest elevations.
Average annual rainfall varies between 1,200 and 2,000 mm, with two wet seasons – October to December and March to June – and two dry seasons – January and February and July to October. The climate is more humid than the surrounding lowlands, and with less distinct wet and dry seasons. Rainfall varies from mountain to mountain, with elevation, and with the direction of prevailing winds.
Flora
The ecoregion consists of montane forests, grasslands, and savannas, transitioning to the East African montane moorlands on the highest peaks. The ecoregion is home to the Afromontane flora, which occurs in the mountains of eastern Africa, and is distinct from the lowland flora.
Plant communities vary with elevation. Plant communities and characteristic species are generally similar from mountain to mountain. The elevational limits for plant communities can vary from mountain to mountain, depending on the mass and height of the mountain, its proximity to the ocean, and its distance from the equator – a phenomenon known as the Massenerhebung effect (mass-elevation effect).