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We attempted in-air-PIXE analysis of SPM using spot samples on a filter-tape mounted in an automated beta-ray absorption mass monitor. Al, Si, S, Fe and Zn, etc., which are of interest for identifying the behavior and characteristics of SPM, were detected on the SPM spot samples on a glass-fiber filter-tape, but the peaks of these elements were nearly identical to those of blank glass-fiber filter-tape. As such, it was difficult to detect elements present in SPM from the X-ray spectra of the spot samples. On the other hand, in the case of a PTFE membrane filter-tape, the S peak was distinct and the Fe peak was also clear, and peaks for elements Al, Mn and Zn, etc., were also confirmed. Consequently, if a method for determining quantity is established, direct multi-elemental analysis by in-air-PIXE of high time-resolution SPM spot samples collected on a PTFE membrane filter-tape mounted in a SPM monitor will be possible.

In order to obtain high time-resolution, i.e., chemical data of atmospheric particulate matter (PM) at one-hour intervals, we carried out direct analysis of suspended particulate matter (SPM) on hourly spot samples on a new type of PTFE ultra-membrane filter-tape mounted in an automated beta-ray absorption mass monitor by conventional PIXE. Analysis of hourly SPM spot samples revealed 20 elements (Na, Mg, Al, Si, S, Cl, K, Ca, Mn, Fe, Co, Ni, Cu, Zn, Ga, As, Se, Br, Sr and Pb) in total. Therefore, we are convinced that the chemical information that is obtained from high time-resolution PM spot samples on a PTFE membrane filter-tape mounted in an automated beta-ray absorption mass monitor will lead to new developments in PM research. Furthermore, elemental data obtained by the high time-resolution along with data for ionic species compositions, and SO₂, NO_X and other gaseous air pollutants at the same level, will make possible the analysis of detailed air pollution phenomenon.

A method of transferring suspended particulate matter (SPM) from the used filter of a beta-absorption mass monitor to a polycarbonate filter for subsequent PIXE analysis has been developed. The method allows determination of the relative elemental composition of SPM. It was demonstrated that PIXE analysis can detect S, Cl, Fe and Zn in SPM sampled over a one-hour period.

To understand the influence of laver aquaculture facilities on the current system and sediment transport in Ariake Bay, field experiments to measure the hydraulic resistance and velocity distribution of a compartment of an aquaculture facility were conducted with numerical simulations of the hydrodynamic environment and suspended particulate matter (SPM) dynamics in local areas around aquaculture facilities and those in the bay scale. The results of the field experiments showed that the resistance coefficient of laver aquaculture nets varied from 0.01 to 0.02, depending on the quantity of laver. The resistance of the nets and poles per a compartment of laver aquaculture facility was of the same order of magnitude as bottom friction, but differences in temporal variation were observed during a tidal cycle. The surface velocities were reduced downstream from the aquaculture facility because of the resistance of the laver nets, and the thickness of this surface boundary layer was approximately 1 m at the downstream end of the facility. The numerical simulation of the head of Ariake Bay showed that the tidal currents and SPM concentrations were reduced in the laver farming ground area, whereas they were increased in the water channel regions because of the relative differences in hydraulic resistance.

While much of the suspended particulate matter found in the ambient air in urban areas has been emitted directly into the atmosphere, some has been formed there by photochemical reactions from gaseous precursor species. Two major components of this secondary particulate matter have been selected for detailed study in the United Kingdom context. These are particulate sulphate, formed from the precursor, sulphur dioxide, and secondary organic aerosols, formed from oxidation of terpenes and aromatic hydrocarbons. A Lagrangian dispersion model has been used to describe the emissions, transport and transformation of SO₂ into particulate sulphate. The origins of the particulate sulphate are delineated in two separate pollution episodes which occurred during 1996. A photochemical trajectory model is used to describe the formation of secondary organic aerosols and to assess the relative contributions from natural biogenic and man-made precursor sources during conditions typical of photochemical pollution episodes.

Satellite remote sensing now allows for the collection of various physical and biological parameters at regional and global scales and at different temporal resolutions which are not accessible to other sampling methods. The first objective of the GlobCoast project (www.foresea.fr/globcoast/) is to assess and analyze the seasonal, inter-annual, and decadal evolution of the global coastal waters in terms of biogeochemical composition as revealed from satellite ocean colour observations. The present study focuses on the suspended particulate matter, SPM, over the global coastal ocean. A new global SPM algorithm, combined with a new atmospheric correction algorithm, have been developed, evaluated, and applied to the MERIS (2002-2012) archive. This unique data set, characterized by a great spatio-temporal coverage, thanks to the applied atmospheric correction algorithm, can then be used for many kind of research activities. Examples of global and regional patterns are then provided.