Centre for Sustainable Aquatic Ecosystems, Harry Butler Institute, Murdoch University, 90 South St, Murdoch 6150, Western Australia, Australia.
Environ Sci Process Impacts. 2019 Jun 19;21(6):1021-1037. doi: 10.1039/c9em00141g.
The enrichment of sediments with nutrients and organic matter (eutrophication) is a key anthropogenic stressor of estuaries worldwide, impacting their sediment condition, ecology and ecosystem service provision. A key challenge for estuary managers and scientists is how to effectively quantify and monitor these changes in ecological condition in a timely and cost-effective manner. We developed a Rapid Assessment Protocol (RAP) for characterizing sediment condition based on the qualitative characteristics of sediment colour, odour and texture. We evaluated its utility for assessing sediment condition, and particularly the degree and effects of sediment enrichment (as quantified by complementary measurements of total C, organic C and total N) across 97 sites throughout a eutrophic microtidal estuary. RAP results were strongly and significantly correlated with the degree of sediment enrichment, with RAP scores correctly identifying the assigned enrichment class (low, medium, high) of 83.5% of sites. More enriched sediments exhibited poorer condition, manifested as significantly lower RAP scores for sediment colour, texture and odour, particularly (but not only) where enrichment coincided with elevated mud content. The RAP was particularly successful (<12% misclassification) at identifying sites with low levels of enrichment, indicating its promise as a first-pass survey approach for identifying potential reference or control sites to support impact assessments. RAP approaches based on qualitative sediment characteristics can provide a useful proxy for the degree and impacts of inorganic and organic enrichment, with potentially broad applicability for supporting timely, cost-effective assessment and monitoring of sediment condition in estuaries worldwide.
营养物质和有机物在沉积物中的富集（富营养化）是全球河口的一个主要人为压力因素，影响着它们的沉积物状况、生态和生态系统服务提供。河口管理者和科学家面临的一个关键挑战是如何及时有效地量化和监测这些生态状况的变化。我们开发了一种基于沉积物颜色、气味和质地等定性特征的快速评估方案（RAP）来描述沉积物状况。我们评估了它在评估沉积物状况方面的实用性，特别是在评估整个富营养化微潮汐河口 97 个地点的沉积物富积程度和影响方面的实用性（通过对总碳、有机碳和总氮的补充测量来量化）。RAP 结果与沉积物富积程度具有很强的显著相关性，83.5%的地点的 RAP 得分正确识别了指定的富积类别（低、中、高）。更富积的沉积物表现出较差的状况，表现为沉积物颜色、质地和气味的 RAP 得分显著降低，特别是（但不仅限于）在富积与高泥含量相吻合的情况下。RAP 在识别低富积水平的地点方面特别成功（<12%的错误分类），表明它有望成为一种用于识别潜在参考或对照地点的初步调查方法，以支持影响评估。基于定性沉积物特征的 RAP 方法可以为无机和有机富积的程度和影响提供有用的替代指标，具有广泛的适用性，可用于支持全球河口沉积物状况的及时、具有成本效益的评估和监测。
