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521.
Gerald Schernewski Arunas Balciunas Dennis Gräwe Ulf Gräwe Kristina Klesse Marcus Schulz Sylvie Wesnigk David Fleet Mirco Haseler Nils Möllman Stefanie Werner 《Journal of Coastal Conservation》2018,22(1):5-25
Major objectives were to provide a comprehensive dataset on beach macro-litter for parts of the southern Baltic Sea and to analyse if the methodology is fully applicable and a suitable monitoring method in the Baltic. We carried out a regular macro litter beach monitoring (OSPAR methodology, 4 time a year) on 35 beaches along the German and Lithuanian Baltic coast over 2–5 years. Additional experiments addressed the subjectivity of the field surveys and spatio-temporal variability on different scales. We observed no seasonality of the data and a monthly compared to a 3-monthly sampling resulted in 3 times higher annual item numbers. Along the Lithuanian coast, the average number of items per survey varied between 138 and 340 and along the German Baltic coast between 7 and 404, with a median value of 47. All data showed a very high spatio-temporal variability. Using the Matrix Scoring Technique we assessed beach litter sources. With 50% tourism and recreation was the most important source. 3D–transport simulations helped to explain the minor role of shipping as a source and, compared to the North Sea, the low numbers of items on German Baltic beaches. Floating litter had a short duration time in the western Baltic Sea and offshore drift dominated. Further, the common regular beach cleanings reduced the potential for local litter accumulation and translocation. We suggest a monitoring system on 14 Baltic beaches in Germany and 2 in Lithuania and provide cost calculations. The analysis of macro-litter in cormorant nesting material and the search for beached dead animals did not show any result. We can conclude that the macro-litter beach monitoring method is less suitable for Baltic beaches and should only serve as a complementary method in combination with others. 相似文献
522.
Woldetsadik Desta Simon Marcel Pierre Knuth Dennis Hailu Hillette Gebresilassie Araya Dejen Asmare Düring Rolf-Alexander 《Environmental geochemistry and health》2021,43(9):3597-3613
Environmental Geochemistry and Health - Khat (Catha edulis) chewing is widespread in the region of East Africa. Even low levels of organochlorine pesticides (OCPs) in khat could induce public... 相似文献
523.
Candis S. Claiborn Dennis Finn Timothy V. Larson Jane Q. Koenig 《Journal of the Air & Waste Management Association (1995)》2013,63(8):1440-1445
ABSTRACT The revised National Ambient Air Quality Standards for PM include fine particulate standards based upon mass measurements of PM25. It is possible in arid and semi-arid regions to observe significant coarse mode intrusion in the PM2.5 measurement. In this work, continuous PM10, PM2.5, and PM1.0 were measured during several windblown dust events in Spokane, WA. PM2 5 constituted ~30% of the PM10 during the dust event days, compared with ~48% on the non-dusty days preceding the dust events. Both PM10 and PM2.5 were enhanced during the dust events. However, PM1.0 was not enhanced during dust storms that originated within the state of Washington. During a dust storm that originated in Asia and impacted Spokane, PM1.0 was also enhanced, although the Asian dust reached Washington during a period of stagnation and poor dispersion, so that local sources were also contributing to high particulate levels. The “intermodal” region of PM, defined as particles ranging in aerodynamic size from 1.0 to 2.5 um, was found to represent a significant fraction of PM25 (~51%) during windblown dust events, compared with 28% during the non-dusty days before the dust events. 相似文献
524.
Environmental and Ecological Statistics - After applying canonical correspondence analysis to metagenomics data with hugely different library sizes (site totals) it became evident that Canoco and... 相似文献