Nigeria Sudan savannah is similar but with shorter grasses and shorter trees. Sahel savannah consists of patches of grass and sand, found in the northeast. In the Sahel region, rain is less than per year and the Sahara Desert is encroaching. In the dry northeast corner of the country lies Lake Chad, which Nigeria shares with Niger, Chad and Cameroon. Nigeria's Delta region, home of the large oil industry, experiences serious oil spills and other environmental problems, which has caused conflict. Waste management including sewage treatment, the linked processes of deforestation and soil degradation, and climate change or global warming are
Far North Region, Cameroon the Mandara Mountains. The Mayo Kébi, Mayo Louti, and their tributaries form part of the Niger River basin. The Louti rises in the Mandaras, passing and swelling the Kébi in the North Province. The Kébi rises south of Yagoua and flows into western Chad. The province's other rivers are part of the Chad Basin. The El Beid River flows northwest from the Kalamalou National Park and forms the northernmost stretch of the border between Cameroon and Nigeria. The Mayo Tsanaga rises south and west of the El Béïd's source and moves eastward at the north of the Diamaré Depression. The