Ecosystem and Biodiversity of the Lake Chad Basin

"Dense" palm trees forest in Niger (Attari, 2006)
Elephants of the Waza National Park (Fosi & Mahamat, 2005)

Ecosystems are defined by the network of interactions among organisms, and between organisms and their environment they can come in any size but usually encompass specific, limited spaces (although some scientists say that the entire planet is an ecosystem).

Biodiversity is the variety of all species on earth. It is the different plants, animals and micro-organisms, their genes, and the terrestrial, marine and freshwater ecosystems of which they are a part.

Biodiversity is both essential for our existence and intrinsically valuable in its own right. This is because biodiversity provides the fundamental building blocks for the many goods and services a healthy environment provides, these include things that are fundamental to our health, like clean air, fresh water and food products, as well as the many other products such as timber and fibre.

Other important services provided by our biodiversity include recreational, cultural and spiritual nourishment that maintain our personal and social wellbeing. Looking after our biodiversity is therefore an important task for all people.

Over the last 40 years Lake Chad Basin has suffered the largest documented decline in biodiversity despite efforts to manage threats and pressures to biodiversity in the basin, it is still in decline.

Vegetation and Flora

Table A. presents the types of vegetation and some of the species found in the Cameroon, Niger, Nigeria and Chadian parts of the Lake Chad Basin. It should however be observed that the terminology used to qualify vegetation differs from one country to the other. For example, the notion of forest does not refer to the same thing in the various countries of the basin; (Photo A). It would be necessary to harmonise the terminology in order for it to always refer to the same vegetation type. In spite of the diversity of nomenclature, the following table recapitulates the main species found in the Basin.

Types of vegetation and some species found in the Lake Chad Basin

Types of vegetation

Some species found

Mountainous vegetation

(Mount Mandara)

Boswellia, Combretum, Acacia albida

Wooded savannah

Acacia senegal, Acacia seyal, Borassus aethiopum Prosopis sp., Acacia nilotica, A. tortillis, Balanites aegyptiaca, Ziziphus spinachristi, Acacia raddiana, Tamarindus indica, Disopiros mespiliformis, Hypheane thebaica, Adansonia digitata

Shrubby steppe

Acacia spp. Balanites aegyptiaca, Ziziphus spp, Calotropsis procera, Aritida spp, Ipomea, spp, Schoenefeldia gracilis, Cordia sinensis, Cadaba farinosa, Pennisetum purpureum, Anogeissus léocarpus, Piliostigma reticulatum, Hypheeane thebaica, Phoenix dactylifora, Hyperthelia dissoltua, Pentzia monodia, Artemisia thiloana, Ephedra thiloana

Grasslands

Echinochloa pyramidis, Hyparrhenia rufa, Oryza longistaminata, Vetvera nigrita, Cenchrus biflorus, Aristida mutabulis, Pergularia tomentosa, Tribulus terrestris, Pennisetum sp.,

Desert (strips of dune)

Acacia radiana, Ziziphus mauritiana, Leptadenia pyrotechnica, Acacia senegal, Malcolmia aegytiaca

Agro-forestry parks

Parkia biglobosa, Prosopis africana, Acacia albida, Tamarindus indica, Hyphaene tebaïca, Borassus aethiopium

"Forest galleries"

Tamarindus indica, Disopiros mespiliformis, Hypheane thebaica, Adansonia digitata, Stipagrostis pungens, Leptadenia pyrotechnica, Calligonum comsum, Maerua crassifolia, Ziziphus mauritiana, Salvadora persica, Caloptropsis procera, etc.

Aquatic Vegetation

- 100 espèces d’algues (phytoplancton) in the lake - Aesschynomene elaphroxylon, Cyperus papyrus, Vosciacuspidata, Phragmites australis, Potamogeton schweinfurthii, Ceratophyllum demerum, Vallisneriaspiralis, Utricularia sp and Nymphea sp.

Vegetation of transition zones

Vertivera nigritana

Riparian forest

Khaya senegalensis, Mitragyna inermis, Diospyros mespiliformes., Acacia niloticus, Palmier Doum, Hyphaene thebaica

Oasis

 

Daniella oliverie, Vitex doniana, Burkea Africana, Cassia senegalensis, Hyphaena thebaica, Acacia spp, Maerua sp., Caparis sp. Calotropis procera, Citrullus colocynthis, Phoenix dactilifera

"Dense" palm trees forest in Niger (Attari, 2006)

Generally, the Lake Chad Basin is characterised by sparse vegetation cover. Here, savannahs (wooded, shrubby, herbaceous), the steppe and the desert can be distinguished. The vegetation is highly modified by human activities (agriculture, grazing, fuel wood collection, etc.). Meanwhile, human activities do not only fragilise the environment, for other activities such as reforestation help in improving it.

Fauna

Knowledge on the fauna of the Lake Chad Basin remains scanty. However, it is generally acknowledged that the fauna of the Lake Chad Basin is rich and diversified. They include species of great international interest including the elephant (Photo B), the lion, the Eland Derby, manatee of Lake Lere, many migratory birds, etc. (Table B). However, several species such as the Addax, the Oryx and dama gazelles have almost disappeared from the Basin (LCBC, 2002). This seems to be the same thing for the black rhinoceros.

Some fauna species found in the Lake Chad Basin

Taxonomic group

Some species found

Mammals

Elephant, lion, giraffe, Eland Derby, cob defassa, patas, galagos of Sénégal, hippopotamus, Addax, wart hog, dorcas gazelles, cheetah, buffalo, grand Koudou, Eland Derby, Sseeved mouflon, damalisques, panther, Serval, manatee,

Reptiles

 

Pythons, Cobra, Nile monitor lizard Varan

Birds

 

Ostrich, bustards, ducks, guinea fowls, many migratory birds

Fishes

 

Lates niloticus, Clarias sp., Heterotis niloticus, Tilapia spp., Oreochromis niloticus, Tetraodon fahaka, Heterotis niloticus, Lates niloticus

Shrimps

 

Macrobrachium niloticus et M. rosenbengii

Amphibians

 

Nile crocodile

Livestock

Grazing in the Lake Chad Basin is characterised by the presence of large and small livestock. The livestock is made up of races of cattle, horses, camels, asins, caprines, ovines, chicken, pigs. The existence of one rare bovine species should be noted, the ‘’Kouri cow’’ which is particular to lake pasture of Lake Chad. This diversity of species fosters the development of transactions beyond national boundaries. Table 8 presents some races bred in the basin. The ‘’Kouri’’ cow is an important species in the Basin but it is endangered. It is not only endemic to Lake Chad but it is reputed to be a milk producer with a daily production that ranges from 4 to 6 litres, whereas the average production of the whole system is between 1 to 2 litres per day (Aminou Tassiou, 1998).

Races of some species reared in the Lake Chad Basin

Species

Kind

Race

Cattle

Cows

Bororo, Fulani, Arab, Kilara, Wadara, Toupouri, Massa, Kouri

Ovine

Sheep

Arab, Peul Ouadah Peul Waïla Kababich, Poulfouli or Massa, Kirdimi

Caprine

Goats

Arab, Moussoro, Baguirmi, Kirdimi

Camel

 

Gorane, Kanem, Mahamid or Manga, Arab or Zebedi

Equine

Horses

Dongolaw, Arab Berbere, Poney of logone

Interaction between Physical and Biological Features

There is great interaction between the various physical and biological features. Vegetation distribution is highly related to the relief, to the soil type and to the presence of water. Thus, there are wooded areas along water bodies and oasis. The presence of water is a factor that favours human settlement of whom their activities are geared towards fishing, grazing, and farming of maize as a priority. In the floodplains, there is generally herbaceous vegetation growing on hydromorphic soil. These zones are good for local development (fishing, grazing and agriculture). They are rich pastures used by graziers during the counter season. These plains are inundated in the rainy season and are exploited for the cultivation of rice and sorghum. The high human pressure in areas where the vegetation and rains favour the development of agricultural, pastoral and fishing activities, cause depletion of the flora and degradation of the soil that are left bare (degraded lands). Crops develop according to the climate of the seasons. Counter season planting takes place at the end of the rainy season. Crop droppings (red sorghum, maize, niebe) are put in place at the end of the dry season.

Problem affecting biological diversity

The basin is home to great biological diversity. The natural flora and fauna are very diverse and include many species of great interest at international level (migratory animals, endemic species), but they are increasingly threatened with degradation following long droughts and uncontrolled human interventions. Meanwhile, human activities are not always negative for biodiversity. Agro-forestry vegetation, and the flora and fauna found therein are the work of man. They contribute to the biological diversification. The same applies to the protection of critical sites, sites that are of interest to the populations, and the creation of protected areas.

Threats on biodiversityElephants of the Waza National Park (Fosi & Mahamat, 2005)

At the level of countries and the sub-region, it is observed that there are marked inadequacies in the conservation of biodiversity. This situation is manifested through poaching, deforestation, stray animals, multiplication of fishing channels, etc. Key threats to biodiversity are expressed in the following manners:

  • Drought and floods that limit productivity of ecosystems ;
  • Rapid population growth that imposes fast extension of farmed areas ;
  • Poor exploitation techniques compromise agricultural, sylvicultural, pastoral as well as fishery potentials ;
  • Extension of cropping reduces the vegetation cover and degrades the biological composition of exploited areas ;
  • Encroachment into protected areas by graziers and fishermen lead to their degradation ;
  • Construction of major hydraulic works disrupts water regimes ;
  • Intensification of the felling of timber to satisfy energy needs and demand for poles aggravates deforestation ;
  • Wanton exploitation of natural resources in complete disregard of regulatory instruments in force compromises efforts towards conservation and rehabilitation of degraded ecosystems.

Human activities do not constitute only threats to biodiversity; they are sometimes also beneficial to conservation or even their restoration. That is the case with many protected areas created or being created in the area. The same applies to various reforestation initiatives that are taking place here and there.

Objectives

  • Restoration and preservation of ecosystems in the Lake Chad Basin
  • Conservation of biodiversity in the Lake Chad Basin
  • Restoration, conservation and sustainable use of bio resources in the Lake Chad Basin

Achievements

  • Development and Implementation of Strategic Action Programme (SAP) for the Lake Chad Basin entitled: Reversal of Land and Water Degradation Trends in the Lake Chad Basin Ecosystem.
  • Sustainable Development Programme of the Lake Chad Basin (PRODEBALT) which cost 60.7 Million UC or 41.84 Billion FCFA.
  • Development and Implementation of the Wetland Ecosystems Management Plan such as Komadugu Yobe Catchment Management Plan, Waza Logone Management Plan and Lake Fitri Management Plan.

Links

  • Wetland Ecosystems Management Plans
  • Strategic Action Programme for the Lake Chad Basin