Department of Earth and Atmospheric Sciences, Cornell University, Ithaca, NY, USA.
Mar Pollut Bull. 2012 Jul;64(7):1348-55. doi: 10.1016/j.marpolbul.2012.05.001. Epub 2012 Jun 8.
In Stone Town, Zanzibar, sewage treatment is minimal, with a biological oxygen demand reduction to 60% and no removal of bacteria or nutrients. Here, Stone Town's sewage pollution was studied by measuring Enterococci and NH(4)(+) concentrations in seawater and δ(15)N of benthic organisms; samples were collected along the Stone Town shoreline and from offshore coral reefs. Public perceptions of sewage pollution were investigated via interviews. Enterococci from the Stone Town shoreline exceeded USEPA guidelines for recreational use. Benthic organisms from two of the four reefs were relatively enriched (δ(15)N>10 ‰), indicative of sewage derived N. δ(15)N values of organisms from Stone Town exceeded 16 ‰. A strong correlation was found between Enterococci and δ(15)N across sites, while step-wise regression indicated rainfall and tidal stage as important predictors for bacterial concentrations. These data provide an important impact assessment from which the efficacy of future policy and management change can be assessed.
在桑给巴尔的石头城，污水处理几乎不存在，生物需氧量（BOD）降低了 60%，而细菌和营养物质仍未被去除。本研究通过测量海水和底栖生物中的粪肠球菌（Enterococci）和氨氮（NH₄⁺）浓度，以及底栖生物的 δ¹⁵N 值，对石头城的污水污染进行了研究；样本取自石头城的海岸线和近海珊瑚礁。通过访谈调查了公众对污水污染的看法。石头城海岸线上的粪肠球菌超过了美国环保署（USEPA）对娱乐用途的指导标准。四个珊瑚礁中的两个礁的底栖生物相对富集（δ¹⁵N＞10‰），表明这些氮来源于污水。来自石头城的生物的 δ¹⁵N 值超过了 16‰。在各个地点之间发现了粪肠球菌和 δ¹⁵N 之间的强烈相关性，而逐步回归表明降雨和潮汐阶段是细菌浓度的重要预测因素。这些数据提供了一个重要的影响评估，从中可以评估未来政策和管理变化的效果。
