نتایج جستجو برای: dust deposition
تعداد نتایج: 133067 فیلتر نتایج به سال:
Isotopic characterization of aerosol mineral particles (atmospheric dust) of varying sizes is essential in classifying source areas, and for determining the source of dust deposited over oceans and icesheets. However, the effect of atmospheric transport on radiogenic isotopic compositions is not well constrained, making provenance interpretation difficult. In order to investigate the isotopic v...
Isotopic ratios of Sr and Nd from lithogenic components of three isochronous core sections recovered from an east–west transect in the Eastern Mediterranean Sea (EMS) have been analyzed. The data are used for a quantitative estimate of the temporal and spatial variation of detrital flux to the EMS, assuming Saharan dust and Aegean/Nile particulate matter as dominant end members. It was establis...
Dust deposition is an important source of phosphorus (P) to many ecosystems. However, there little evidence dust-derived P-containing minerals in soils. Here we studied P forms along a well-described climatic gradient on Hawaii, which also dust gradient. Soil mineralogy and soil from six sites the were analyzed with bulk (X-ray diffraction K-edge X-ray absorption near edge structure) microscale...
Introduction: Physical, chemical and ecological changes on dust deposition sites are one of the many problems caused by the occurrence of dust phenomena in arid areas. The entrance of additional salts to the ecosystem by dust, makes increased salinity and imbalanced of salts in the growth environment of plants. The purpose of this study is to determine the seasonal variations in the amount of s...
Mineral dust aerosols impact Earth's radiation budget through interactions with clouds, ecosystems, and radiation, which constitutes a substantial uncertainty in understanding past and predicting future climate changes. One of the causes of this large uncertainty is that the size distribution of emitted dust aerosols is poorly understood. The present study shows that regional and global circula...
Atmospheric dust loadings play a crucial role in the global climate system. Southern South America is a key dust source, however, dust deposition rates remain poorly quantified since the last glacial termination (~17 kyr ago), an important timeframe to anticipate future climate changes. Here we use isotope and element geochemistry in a peat archive from Tierra del Fuego, to reconstruct atmosphe...
The spatial distribution and deposition of lead and zinc emitted from the Trail smelter, British Columbia, Canada, was studied by strategically locating moss bags in the area surrounding the smelter and monitoring the deposition of elements every three months. A combined diffusion/distribution model was applied to estimate the relative contribution of stack-emitted material and material emitted...
[1] Dust fluxes are of wide interest because of the effects of dust on climate, oceanic primary productivity, terrestrial biogeochemical cycles, and regolith composition. Estimating long‐ term dust deposition rates, however, can be difficult, especially in steep, eroding terrain. Here we present a geochemical mass balance method for estimating long‐term average rates of dust incorporation into ...
As human impact have been increasing strongly over the last decades, it is crucial to distinguish human-induced dust sources from natural ones in order to define the boundary of a newly proposed epoch - the Anthropocene. Here, we track anthropogenic signatures and natural geochemical anomalies in the Mukhrino peatland, Western Siberia. Human activity was recorded there from cal AD 1958 (±6). An...
This work was motivated by the need to better reconcile emission factors for fugitive dust with the amount of geologic material found on ambient filter samples. The deposition of particulate matter with aerodynamic diameter less than or equal to 10 microm (PM10), generated by travel over an unpaved road, over the first 100 m of transport downwind of the road was examined at Ft. Bliss, near El P...
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