Chad has several regions: a desert zone in the north, an arid Sahelian belt in the centre and a more fertile Sudanian Savanna zone in the south. Although in the 21st century it covers only 17,806 square kilometres (6,875 sq mi), and its surface area is subject to heavy seasonal fluctuations, Lake Chad is Africa's second largest wetland. The region's tall grasses and extensive marshes make it favourable for birds, reptiles, and large mammals. Chad's animal and plant life correspond to the three climatic zones. In the Saharan region, the only flora is the date-palm groves of the oasis. Palms and acacia trees grow in the Sahelian region. The southern, or Sudanic, zone consists of broad grasslands or prairies suitable for grazing. As of 2002, there were at least 134 species of mammals, 509 species of birds (354 species of residents and 155 migrants), and over 1,600 species of plants throughout the country. Extensive deforestation has resulted in loss of trees such as acacias, baobab, dates and palm trees. This has also caused loss of natural habitat for wild animals; one of the main reasons for this is also hunting and livestock farming by increasing human settlements. Animals like lions, leopards and rhino have been almost decimated. Efforts have been made by the United Nations Food and Agricultural Organization to improve relations between farmers, agro-pastoralists and pastoralists in the Zakouma National Park (ZNP), Siniaka-Minia, and Aouk reserve in southeastern Chad to promote sustainable development. As part of the national conservation effort, more than 1.2 million trees have been replanted to check the advancement of the desert, which incidentally also helps the local economy by way of financial return from acacia trees, which produce gum arabic, and also from fruit trees. (Wikipedia)