Are peri-urban mangrove forests viable? Effects of sewage pollution and wood exploitation on the structure and development of the mangroves of Mombasa (Kenya)

The vegetation, functional and socio-economic aspects of the peri-urban mangroves of Tudor creek in Mombasa were studied. The mangroves of Tudor creek are degraded due to long-term impacts of unregulated wood harvest, raw domestic sewage pollution and siltation. The unregulated exploitation of mangrove wood by locals undervalues the ecosystem goods and services. However, despite being degraded, the mangroves of Tudor creek are still productive and are comparable to similar forests globally. The study further shows that raw domestic sewage may not have a significant impact on mangrove productivity, but may alter leaf nitrates content, with implication on nutrients cycling within the system. It is recommended that ‘adaptive management' is the best strategy to manage peri-urban mangroves. Valuing the ecosystem goods and services, and assigning legally binding responsibility on users may ensure the long-term sustainability of peri-urban ecosystems