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
Constitution of Chad Rights. The constitutional endorsement of the Universal Declaration of Human Rights is an aspect Chad has in common with many national constitutions: among African countries, it is endorsed by Benin, Burkina Faso, Burundi, Cameroon, Cape Verde, Comoros, Congo-Brazzaville, Côte d'Ivoire, Equatorial Guinea, Ethiopia, Gabon, Guinea, Guinea-Bissau, Mali, Mauritania, Niger, Rwanda, Senegal and Tanzania. A problem is represented by the implementation of the human rights norms, as there is a legal vacuum due to the lack of the necessary provisions in the Criminal Code, which has to be amended so that national legislation is put into line with the international human