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Geology topics

Alison W. Watts

Publications and source records attributed to Alison W. Watts.

3 recordsLinked to original sources

What is eDNA method standardization and why do we need it?

The rapid advancement of environmental DNA ( eDNA ) science in the past two decades has inspired a concomitant growth in the development of eDNA sampling and analytical methods. However, these methods are often developed by individual laboratories or institutions, which can isolate protocols within programmes, agencies or regions and prevent the beneficial exchange of data and ideas. Recent efforts to advance national and international coordination have resulted in a groundswell of standardisation efforts, but there is still considerable confusion around the role of formal standards for regulatory or research applications. With this commentary, we hope to provide clarity on the terminology used in standardisation discussions, including the differences between formal standards and best practice guidelines. Additionally, we discuss how eDNA method choice may be informed by environmental management scenarios and review examples of formal eDNA method standards being used to inform management action. The eDNA community now has an opportunity to develop a roadmap for method development to help close standardisation gaps, advance eDNA method adoption and accelerate our ability to monitor biological life at the scales our current environmental challenges demand.

Metabarcoding and Metagenomics

The MIEM guidelines: Minimum information for reporting of environmental metabarcoding data

Environmental DNA ( eDNA ) and RNA ( eRNA ) metabarcoding has become a popular tool for assessing biodiversity from environmental samples, but inconsistent documentation of methods, data and metadata makes results difficult to reproduce and synthesise. A working group of scientists have collaborated to produce a set of minimum reporting guidelines for the constituent steps of metabarcoding workflows, from the physical layout of laboratories through to data archiving. We emphasise how reporting the suite of data and metadata should adhere to findable, accessible, interoperable and reproducible ( FAIR ) data standards, thereby providing context for evaluating and understanding study results. An overview of the documentation considerations for each workflow step is presented and then summarised in a checklist that can accompany a published study or report. Ensuring workflows are transparent and documented is critical to reproducible research and should allow for more efficient uptake of metabarcoding data into management decision-making.

Metabarcoding and Metagenomics

Coal-tar-based pavement sealcoat and PAHs: implications for the environment, human health, and stormwater management

Coal-tar-based sealcoat products, widely used in the central and eastern U.S. on parking lots, driveways, and even playgrounds, are typically 20−35% coal-tar pitch, a known human carcinogen that contains about 200 polycyclic aromatic hydrocarbon (PAH) compounds. Research continues to identify environmental compartments—including stormwater runoff, lake sediment, soil, house dust, and most recently, air—contaminated by PAHs from coal-tar-based sealcoat and to demonstrate potential risks to biological communities and human health. In many cases, the levels of contamination associated with sealed pavement are striking relative to levels near unsealed pavement: PAH concentrations in air over pavement with freshly applied coal-tar-based sealcoat, for example, were hundreds to thousands of times higher than those in air over unsealed pavement. Even a small amount of sealcoated pavement can be the dominant source of PAHs to sediment in stormwater-retention ponds; proper disposal of such PAH-contaminated sediment can be extremely costly. Several local governments, the District of Columbia, and the State of Washington have banned use of these products, and several national and regional hardware and home-improvement retailers have voluntarily ceased selling them.

Environmental Science & Technology