MA in Climate Change and Global Sustainability
Seagrass meadows are located abundantly in Zanzibar, Tanzania and provide essential ecosystem services, such as sediment nutrient enrichment and blue carbon sequestration. However, seagrasses have been less researched or protected than other marine ecosystems. Although environmental variables affect seagrass health, evidence suggests that anthropogenic impacts are their greatest threats. The rapid expansion of seaweed farming and tourism and widespread use of harmful small-scale fishing practices in Zanzibar have contributed to the degradation and removal of seagrass meadows, disrupted coastal marine food chains, and reduced local biodiversity that seagrasses support. Public or private marine protected areas (MPAs) protect most of Zanzibar’s coastal marine ecosystems, yet evidence is unclear whether MPAs effectively conserve marine ecosystems. Using geographic information systems (GIS) to estimate the change in percent of seagrass cover from 2006 to 2019, we conducted Spearman’s rank correlation analyses to identify whether seagrass degradation was correlated with seaweed farming, fishing, or tourism and whether MPA management plans were protective. Tourism was negatively correlated with seagrass cover, r(9) = -0.74, p = 0.044, suggesting that tourism is an important driver of seagrass declines in Zanzibar. No other variables were significantly correlated with seagrass cover decline. To improve the management of seagrass meadows, plans must identify seagrasses as critical ecosystems, expand seagrass restoration projects, and address harmful practices in the tourism industry and other human impacts.
Environmental Health and Protection | Environmental Monitoring | Environmental Studies | Natural Resources Management and Policy | Sustainability
Purvis, Danielle and Jiddawi, Narriman, "Current State of Seagrasses in Zanzibar: Impacts of Coastal Economic Activities and Marine Protected Areas on Seagrass Cover" (2021). Capstone Collection. 3239.