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USGS2025

Risks of per- and polyfluoroalkyl substance exposure through marine fish consumption

Global food trade expansion has enriched diets worldwide but also heightened concerns about contaminant spread. Per- and polyfluoroalkyl substances (PFAS) can persist in the environment for decades, yet their risks through food trade remain unclear. The global median estimated daily intake (EDI) of C8-PFAS (perfluorooctanoic acid and perfluorooctane sulfonate) (0.023 nanograms per kilograms per day) was mapped from 212 marine fish species, which indicated higher EDIs in North America, Oceania, and Europe. Furthermore, European countries play a pivotal role in C8-PFAS trade flows, markedly reshaping exposure pathways and driving increased exposure in many nations. These dynamics highlight the importance of establishing food-safety regulations and international trade standards. Although perfluorooctane sulfonate hazard index decreased by 72% after its 2009 regulations, unregulated long-chain PFAS continue to pose elevated risks.

Science↗

USGS2025

Applications of unoccupied aerial systems (UAS) in landscape ecology: A review of recent research, challenges and emerging opportunities

Context Unoccupied aerial systems/vehicles (UAS/UAV, a.k.a. drones) have become an increasingly popular tool for ecological research. But much of the recent research is concerned with developing mapping and detection approaches, with few studies attempting to link UAS data to ecosystem processes and function. Landscape ecologists have long used high resolution imagery and spatial analyses to address ecological questions and are therefore uniquely positioned to advance UAS research for ecological applications. Objectives The review objectives are to: (1) provide background on how UAS are used in landscape ecological studies, (2) identify major advancements and research gaps, and (3) discuss ways to better facilitate the use of UAS in landscape ecology research. Methods We conducted a systematic review based on PRISMA guidelines using key search terms that are unique to landscape ecology research. We reviewed only papers that applied UAS data to investigate questions about ecological patterns, processes, or function. Results We summarize metadata from 161 papers that fit our review criteria. We highlight and discuss major research themes and applications, sensors and data collection techniques, image processing, feature extraction and spatial analysis, image fusion and satellite scaling, and open data and software. Conclusion We observed a diversity of UAS methods, applications, and creative spatial modeling and analysis approaches. Key aspects of UAS research in landscape ecology include modeling wildlife micro-habitats, scaling of ecosystem functions, landscape and geomorphic change detection, integrating UAS with historical aerial and satellite imagery, and novel applications of spatial statistics.

Landscape Ecology↗