Abstract
Abstract Marine biodiversity is under increasing threat as the area covered by corals diminishes under pressure from climate change and human activities, most of which lead to marine pollution. In Kenya, marine protected areas (MPAs) are the key strategy used to protect coral reefs and biodiversity. However, MPAs’ effectiveness to prevent pollution of the reefs has not been specifically assessed. We determined if the levels of surrogates of human-source pollution, i.e. E. coli and nutrient concentrations on Kenyan coral reefs, varied with increasing levels of marine protection at the Kilifi creek (least protection), Malindi Reserve (moderate protection) and Kuruwitu Conservancy (strictest protection). The most probable number (MPN) of E. coli was estimated by serial dilution while nitrate and orthophosphate concentrations were determined spectrophotometrically. As protection increased from “least”, to “moderate” and “strictest”, E. coli concentrations (MPN/100 mL) decreased from 29, to 16 and undetectable, while mean orthophosphate concentrations increased from 0.326, to 0.422, and 0.524 mg/L, respectively. Mean nitrate concentrations, on the other hand, showed no trend with protection. These results suggest the potential of marine protection to mitigate coral reef pollution, especially from microbes. They also point to the possibility that multiple sources of pollution exist on which marine protection may have little or no effect. Significantly, this pilot study points to the need for improved study design to definitively determine role MPAs may play in protecting against pollution.
Highlights
The Western Indian Ocean (WIO) hosts the second largest coral reef biodiversity globally (Obura, 2012) and holds potential wealth for the region due to the significant economic role that oceans play to support jobs, tourism, and fisheries
The coral reef sites studied differed in both surrogates of humansource pollution investigated
E. coli concentrations decreased as the level of protection increased
Summary
The Western Indian Ocean (WIO) hosts the second largest coral reef biodiversity globally (Obura, 2012) and holds potential wealth for the region due to the significant economic role that oceans play to support jobs, tourism, and fisheries. The oceans’ economic value depends on healthy coral reefs (Obura et al, 2017), which cover only 0.1% of the ocean floor but host at least 25% of all marine biodiversity (Hoegh-guldberg et al, 2017), provide goods and services such as seafood, recreational possibilities, coastal protection, and aesthetic and cultural benefits (Moberg and Folke, 1999). Marine Protected Areas and Human-Source Pollution and/or death following episodes of elevated sea surface temperatures (Hughes et al, 2017). The scale of human impacts is, bound to intensify over time as temperatures are expected to keep rising, while the human population increases on coastal zones attracted by the goods and services of the marine ecosystems (Neumann et al, 2015)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
