Environmental Issues in The Niger Delta - Loss of Mangrove Forests

Loss of Mangrove Forests

Vegetation in the Niger River Delta consists of extensive mangrove forests, brackish swamp forests, and rainforests. The large expanses of mangrove forests are estimated to cover approximately 5,000 to 8,580 km² of land. Mangroves remain very important to the indigenous people of Nigeria as well as to the various organisms that inhabit these ecosystems.

Human impact from poor land management upstream coupled with the constant pollution of petroleum has caused five to ten percent of these mangrove forests to disappear. The volatile, quickly penetrating, and viscous properties of petroleum have wiped out large areas of vegetation. When spills occur close to and within the drainage basin, the hydrologic force of both the river and tides force spilled petroleum to move up into areas of vegetation.

Mangrove forests are included in a highly complex trophic system. If oil directly affects any organism within an ecosystem, it can indirectly affect a host of other organisms. These floral communities rely on nutrient cycling, clean water, sunlight, and proper substrates. With ideal conditions they offer habitat structure, and input of energy via photosynthesis to the organisms they interact with. The effects of petroleum spills on mangroves are known to acidify the soils, halt cellular respiration, and starve roots of vital oxygen.

An area of mangroves that has been destroyed by petroleum may be susceptible to other problems. These areas may not be suitable for any native plant growth until bacteria and microorganisms can remediate the conditions. A particular species of mangrove, Rhizophora racemosa lives higher in the delta system. As the soils supporting R. racemosa become too toxic, a non-native invasive species of palm, Nypa fruticans, quickly colonizes the area. This invasive species has a shallower root system that destabilizes the banks along the waterways, further impacting sediment distribution lower in the delta system. N. fruticans also impedes navigation and decreases overall biodiversity. In places where N. fruticans has invaded, communities are investigating how the palm can be used by local people.

The loss of mangrove forests is not only degrading life for plants and animals, but for humans as well. These systems are highly valued by the indigenous people living in the affected areas. Mangrove forests have been a major source of wood for local people. They also are important to a variety of species vital to subsistence practices for local indigenous groups, who unfortunately see little to none of the economic benefits of petroleum. Mangroves also provide essential habitat for rare and endangered species like the manatee and pygmy hippopotamus. Poor policy decisions regarding the allocation of petroleum revenue has caused political unrest in Nigeria. This clash among governing bodies, oil corporations, and the people of Nigeria has resulted in sabotage to petroleum pipelines, further exacerbating the threat to mangrove forests.

The future for mangrove forests and other floral communities is not all negative. Local and outside groups have provided funds and labor to remediate and restore the destroyed mangrove swamps. The federal government of Nigeria established the Niger Delta Development Commission (NDDC) in 2000 which aims to suppress the environmental and ecological impacts petroleum has had in the region. Governmental and nongovernmental organizations have also utilized technology to identify the source and movement of petroleum spills.