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The suspended particulate organic matter (SPOM) in transitional waters such as the Maryland Coastal Bays (MCBs) is derived from allochthonous and autochthonous sources. Little is known, however, about the contribution of terrestrially derived organic matter to SPOM in the MCBs. The sources of SPOM in the MCBs were evaluated using stable isotope ratios of nitrogen (&delta, 15N) and carbon (&delta, 13C), and C/N molar ratios. The values of SPOM &delta, 15N, &delta, 13C and C/N ratios from samples collected seasonally (July 2014 to October 2017) at 13 sites ranged from &minus, 0.58 to 10.51&permil, &minus, 26.85 to &minus, 20.33&permil, and 1.67 to 11.36, respectively, indicating a mixture of terrestrial SPOM transported by tributaries, marine organic matter from phytoplankton, and sewage. SPOM &delta, 13C levels less than &minus, 24&permil, suggesting the dominance of terrestrially derived carbon, occurred mainly at sites close to the mouths of tributaries, and were less depleted at sites near the ocean. The mean value of SPOM &delta, 13C was higher in October 2014 (&minus, 22.76&permil, ) than in October 2015 (&minus, 24.65&permil, ) and 2016 (&minus, 24.57&permil, ) likely due to differences in river discharge. Much lower values (&lt, 4&permil, ) of &delta, 15N observed in February 2016 coincided with a high freshwater inflow that accompanied a major storm, indicating a strong influence of untreated sewage. Results from a two end-member mixing model suggest that on average, the SPOM in the MCBs is composed of 44% terrestrial materials with the highest percent contributions in October 2015 and 2016 (61%), and lowest (28%) in July 2015. The contribution of terrestrial materials to the SPOM was highest (58%) near the mouth of St. Martin River and lowest (25%) near the Ocean City inlet. SPOM composition and distribution in MCBs are, therefore, a function of land use, freshwater inflow, and water circulation that influence in situ phytoplankton production, and the transport and distribution of terrestrially derived materials.

International audience; Ocean wave activity excites seismic waves that propagate through the solid earth, known as microseismic noise. Here we use a network of 57 ocean bottom seismometers (OBS) deployed around La Réunion Island in the southwest Indian Ocean to investigate the noise generated in the secondary microseismic band as a tropical cyclone moved over the network. Spectral and polarization analyses show that microseisms strongly increase in the 0.1–0.35 Hz frequency band as the cyclone approaches and that this noise is composed of both compressional and surface waves, confirming theoretical predictions. We infer the location of maximum noise amplitude in space and time and show that it roughly coincides with the location of maximum ocean wave interactions. Although this analysis was retrospectively performed, microseisms recorded on the seafloor can be considered a novel source of information for future real-time tracking and monitoring of major storms, complementing atmospheric, oceanographic, and satellite observations.