Dynamics of Dissolved Organic Matter and Microbes in Seawater through Sub-Micron Particle Size Analyses

Digital Repository Service at National Institute of Oceanography (India)

Goes, J.I.; Balch, W.M.; Vaughn, J.M.; Gomes, H.R.

-78. Hansell, D.A. and Carlson, C.A., (1998) Deep-ocean gradients in the concentration of dissolved organic carbon. Nature, 395, 263-266. J. E. (1977) Characterization of suspended matter in the Gulf of Mexico ? II. Particles size analysis of suspended matter.... and Morris, I. (1980) Extracellular release of carbon by marine phytoplankton: a physiological approach. Limnol. Oceanogr., 25, 262-279. Maurer, L. G. (1976) Organic polymers in seawater: changes with depth in the Gulf of Mexico. Deep-Sea Res., 23, 1059...

Radium isotopes in suspended matter in an estuarine system in the southwest of Spain

International Nuclear Information System (INIS)

Perianez, R.; Garcia-Leon, M.; Abril, J.M.

1994-01-01

The presence of 226 Ra and 224 Ra in suspended matter from an estuarine system which surrounds a phosphate fertilizer complex has been investigated. The results have confirmed an important radioactive impact from the industrial complex, since up to 2.5 Bq 226 Ra/g suspended matter (dry) has been measured. The influence of tides and seasonal conditions, through changes in salinity, has been found to be relevant. The distribution coefficients for 226 Ra between the suspended matter and the river water have been calculated. The values are in agreement by order of magnitude with those found in the literature, but they clearly depend on tidal state and seasonal conditions. (author) 14 refs.; 6 figs.; 2 tabs

Directly transport of suspended matter from the Yangtze River to the Okinawa trough post-major flood '98: evidence from stable isotopes and C/N ratios

International Nuclear Information System (INIS)

Cai Deling; Shi Xuefa; Song Xiaohong

2007-01-01

Water column concentrations of total suspended matter (TSM), particulate organic carbon (POC), particulate nitrogen (PN) and their stable isotopic compositions (δ 13 C and δ 15 N) are measured at two to five different depths in the Yellow Sea and East China Seas and Yangtze Estuary to clarify the effect of '98 Yangtze great flood on the transport of suspended matter in the Yellow Sea and East China Sea. Suspended matters are collected to analyze the distributions of TSM, POC, PN and salinity throughout the Yellow Sea and East China Sea in the autumn of 1998. There are marked positive correlations (r=0.89-0.98) among TSM, POC and PN, but negative relationships (r=-0.29 - -0.59) between TSM and salinity. These results conclude that the POC and PN were controlled primarily by the concentrations of TSM. The C/N ratios of particulate organic matter have a negative linear correlation with PN% (r=-0.44 - -0.71), but no correlation with POC%, which suggests C/N ratios are mainly controlled by PN%. There are distinct positive correlations between δ 15 N and POC% or PN% in surface water (r=0.36 and 0.24, p<0.01, respectively), however, the correlation do not exist in more deeper depths. In indicates that δ 15 N PN could be changed by a lot of factors, such as nutrient availability, nitrification, denitrification, different material sources and so on, except decomposition of organic matter. The distributions of C/N ratios and δ 13 C values of the particulate organic matter suggest that suspended matters from Yangtze River could be transported directly into the Okinawa Trough under the condition of '98 Yangtze major flood, which break through the foregone knowledge obtained under the normal hydrological condition. (authors)

[Distribution and origin of polycyclic aromatic hydrocarbons in suspended particulate matters from the Yangtze estuarine and nearby coastal areas].

Science.gov (United States)

Ou, Dong-ni; Liu, Min; Xu, Shi-yuan; Cheng, Shu-bo; Hou, Li-jun; Gao, Lei

2008-09-01

Parent PAHs have been quantified in suspended particulate matters from the Yangtze Estuarine and Coastal Areas. The results show that the concentrations of total PAHs ranged from 2278.79-14293.98 ng/g, and were characterized by greatest content near sewage discharge point with trend to decrease by increasing distance. As for PAHs composition, 4-6 rings PAHs were dominant while 2-3 rings PAHs were relative low. Cluster analysis found that except urban sewage discharge, the hydrodynamic force was influencing PAHs distribution patterns. Moreover, the content of suspended particulate matters, organic carbon and soot carbon of suspended particulate matters also play the important roles in PAHs distribution from the Yangtze estuarine and nearby coastal areas. Principal component analysis and PAH ratios demonstrated that uncompleted combustion of fossil fuels was the main source of PAHs in coastal areas, as well as a few anthropogenic releases of oil and oil products. Ecological risk assessment indicated that most of PAH compounds exceeded the effects range ER-L values and ISQV-L values, which might certain potential damage to the Yangtze Estuary ecosystem.

Suspended particulate matter flocculation in a natural tidal wetland located in the San Francisco Estuary

Science.gov (United States)

Saraceno, J.; Bergamaschi, B. A.; Wright, S. A.; Boss, E.; Downing, B. D.; Fleck, J.; Ganju, N. K.

2011-12-01

Suspended mineral and algal particles together comprise suspended particulate matter (SPM). The SPM size distribution influences the quantity and color of light penetration and the adsorption and transport of contaminants such as pesticides and metals. It is widely known that interaction with wetlands alters the size distribution and quality of particles through local primary production, differential settling and particle aggregation, however, our understanding of how tidal wetland processes affect SPM quantity and size spectra has been hampered by the difficulty of directly observing these parameters at tidal time scales. To evaluate how SPM concentration and size varied over tidal time scales and to better understand the relationship between organic matter and sediment characteristics, simultaneous measurements of dissolved organic matter, SPM concentration and organic content as well as in situ surrogates of particle concentration (turbidity, particulate attenuation, volume concentration) and particle size (laser diffraction) were carried out with measurements of current velocity (acoustic Doppler velocity meter) in the main channel of Brown's Island located in the western San Joaquin/Sacramento River Delta, CA. The study period coincided with high estuary sediment levels following a significant precipitation runoff event. In the Brown Island wetland, particle concentration and size dynamics were tied to variations in water level and velocity. Turbidity and attenuation covaried with the volume concentration of particles smaller than 33 um, which on average represented greater than 50% of particle population by volume. On average, these SPM concentration surrogates were three times higher in flood water than in ebb water; consistent with a loss of fine particles on the island. Following the highest flood tide, the decrease in fine particles was coincident with an increase in the concentration of particles larger than 130 um; a finding consistent with particle

Nature of suspended particulate matter and concentrations of heavy ...

African Journals Online (AJOL)

The concentrations of metals in bottom sediment in the Tanzanian waters of Lake Victoria and the nature of suspended particulate matter (SPM) were analysed. The objective of the study was to compare levels of metals in sediment from different locations and to establish their sources. Metal concentrations were higher in ...

Determination of the origin of suspended matter and sediments in the Elbe estuary using natural tracers

International Nuclear Information System (INIS)

Schoer, J.H.

1990-01-01

The clay mineral composition, the concentrations of carbonates, the proportions of carbon and oxygen isotopes in carbonates and organic matter, as well as the concentrations of different nonanthropogenic metals were used to determine the origin of different grain size fractions of sediments and suspended matter in the Elbe estuary. Analysis of the smectite/kaolinite proportion revealed that solid material · 2 μm from the North Sea is transported up the river, about 40 km beyond the most upstream position of the salt wedge. In the 2-20 μm fraction, the 16 O/ 18 O ratio in carbonates and the kaolinite/chlorite proportion demonstrate a transport of North Sea material between 40 and 20 km upstream of the marine water limit. The transport behavior of the 20-63 μm grain size fraction could be determined by the hafnium concentration, representative for the heavy mineral zircon. In this case, the transport distance beyond the salt wedge was up to 20 km. No information was available on the origin of the fine organic matter, whereas the coarser fractions were derived primarily from debris of salt marsh vegetation. The results demonstrate that in the Elbe estuary mixing between marine and fluvial solid material occurs upstream of the salt wedge and is significantly responsible for the observed decrease in the concentration of various pollutants in sediments and suspended matter along the estuary. The cause of the upstream particle transport is probably a scour lag mechanism based on asymmetries of the flood- and ebb-tide current distribution, especially their differing maximum velocities

Experimental Study of Soil Organic Matter Loss From Cultivated Field Plots In The Venezuelan Andes.

Science.gov (United States)

Bellanger, B.; Huon, S.; Velasquez, F.; Vallès, V.; Girardin A, C.; Mariotti, A. B.

The question of discriminating sources of organic matter in suspended particles of stream flows can be addressed by using total organic carbon (TOC) concentration and stable isotope (13C, 15N) measurements when constant fluxes of organic matter supply can be assumed. However, little is known on the dynamics of organic matter release during soil erosion and on the temporal stability of its isotopic signature. In this study, we have monitored soil organic carbon loss and water runoff using natural rainfall events on three experimental field plots with different vegetation cover (bare soil, maize and coffee fields), set up on natural slopes of a tropical mountainous watershed in NW Venezuela (09°13'32'' ­ 09°10'00''N, 70°13'49'' ­ 70°18'34''W). Runoff and soil loss are markedly superior for the bare field plot than for the coffee field plot: by a factor 15 ­ 36, respectively, for the five-month experiment, and by a factor 30 ­ 120, respectively, during a single rainfall event experiment. Since runoff and soil organic matter loss are closely linked during most of the flow (at the time scales of this study), TOC concentration in suspended matter is constant. Furthermore, stable isotope compositions reflect those of top-soil organic matter from which they originate.

Modelling the transport of suspended particulate matter by the Rhone River plume (France). Implications for pollutant dispersion

International Nuclear Information System (INIS)

Perianez, R.

2005-01-01

A model to simulate the transport of suspended particulate matter by the Rhone River plume has been developed. The model solves the 3D hydrodynamic equations, including baroclinic terms and a 1-equation turbulence model, and the suspended matter equations including advection/diffusion of particles, settling and deposition. Four particle classes are considered simultaneously according to observations in the Rhone. Computed currents, salinity and particle distributions are, in general, in good agreement with observations or previous calculations. The model also provides sedimentation rates and the distribution of different particle classes over the sea bed. It has been found that high sedimentation rates close to the river mouth are due to coarse particles that sink rapidly. Computed sedimentation rates are also similar to those derived from observations. The model has been applied to simulate the transport of radionuclides by the plume, since suspended matter is the main vector for them. The radionuclide transport model, previously described and validated, includes exchanges of radionuclides between water, suspended matter and bottom sediment described in terms of kinetic rates. A new feature is the explicit inclusion of the dependence of kinetic rates upon salinity. The model has been applied to 137 Cs and 239,240 Pu. Results are, in general, in good agreement with observations. - A model has been developed to simulate transport of suspended particulate matter in the Rhone River plume

Intra-annual variability of carbon and nitrogen stable isotopes in suspended organic matter in waters of the western continental shelf of India

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M. V. Maya

2011-11-01

Full Text Available Intra-annual variations of δ¹³C and δ¹⁵N of water-column suspended particulate organic matter (SPOM have been investigated to understand the biogeochemical cycling of C and N in the Western Continental Shelf of India (WCSI. The key issues being addressed are: how the δ¹⁵N of SPOM is affected by seasonally varying processes of organic matter production and respiration and how it relates to the δ¹⁵N of sedimentary organic matter that appears to show a decreasing trend despite an apparent intensification of seasonal oxygen deficiency over the past few decades? A secondary objective was to evaluate the sources of organic carbon. Elemental carbon and nitrogen concentrations, C/N ratios in SPOM, along with ancillary chemical and biological variables including phytoplankton pigment abundance were also determined on a seasonal basis (from March 2007 to September 2008, with the partial exception of the southwest (SW monsoon period. The results reveal significant shifts in isotopic signatures, especially δ¹⁵N, of SPOM before and after the onset of SW monsoon. Very low δ¹⁵N values, reaching a minimum of −4.17 ‰, are found during the pre-monsoon period. Our results provide the first direct evidence for the addition of substantial amounts of isotopically light nitrogen by the diazotrophs, especially Trichodesmium, in the region. The δ¹⁵N of SPOM is generally lower than the mean value (7.38 ‰ for surficial sediments, presumably because of diagenetic enrichment. The results support the view that sedimentary δ¹⁵N may not necessarily reflect denitrification intensity in the overlying waters due to diverse sources of nitrogen and variability of its isotopic composition. The observed intra-annual variability of δ¹³C of SPOM during the pre-monsoon and post-monsoon periods is generally small. Phytoplankton production and probably species

Identifying the source, transport path and sinks of sewage derived organic matter

International Nuclear Information System (INIS)

Mudge, Stephen M.; Duce, Caroline E.

2005-01-01

Since sewage discharges can significantly contribute to the contaminant loadings in coastal areas, it is important to identify sources, pathways and environmental sinks. Sterol and fatty alcohol biomarkers were quantified in source materials, suspended sediments and settling matter from the Ria Formosa Lagoon. Simple ratios between key biomarkers including 5β-coprostanol, cholesterol and epi-coprostanol were able to identify the sewage sources and effected deposition sites. Multivariate methods (PCA) were used to identify co-varying sites. PLS analysis using the sewage discharge as the signature indicated ∼ 25% of the variance in the sites could be predicted by the sewage signature. A new source of sewage derived organic matter was found with a high sewage predictable signature. The suspended sediments had relatively low sewage signatures as the material was diluted with other organic matter from in situ production. From a management viewpoint, PLS provides a useful tool in identifying the pathways and accumulation sites for such contaminants. - Multivariate statistical analysis was used to identify pathways and accumulation sites for contaminants in coastal waters

Distribution and transportation of suspended sediment

International Nuclear Information System (INIS)

Schubel, J.R.

1975-01-01

A number of studies of the distribution and character of suspended matter in the waters of the Atlantic shelf have documented the variations in the concentration of total suspended matter in both time and space. Very little is known, however, about the ultimate sources of inorganic suspended matter, and even less is known about the routes and rates of suspended sediment transport in shelf waters. Suspended particulate matter constitutes a potential vehicle for the transfer of energy-associated contaminants, radionuclides and oil, back to the coast and therefore to man. The concentrations of total suspended matter in shelf waters are typically so low, however, that the mechanism is ineffective. Studies of suspended particulate matter have a high scientific priority, but in this investigator's opinion the state of knowledge is adequate for preparation of the environmental impact statements that would be required for siting of offshore nuclear power plants and for oil drilling on the Atlantic Continental Shelf

Small scale patches of suspended matter and phytoplankton in the Elbe river estuary, German Bight and tidal flats

Energy Technology Data Exchange (ETDEWEB)

Doerffer, R; Fischer, J; Stoessel, M; Brockmann, C [GKSS-Forschungszentrum Geesthacht GmbH, Geesthacht-Tesperhude (Germany, F.R.); Grassl, H [Max-Planck-Institut fuer Meteorologie, Hamburg (Germany, F.R.)

1989-01-01

Thematic mapper and ship data has been used to study small scale features in coastal waters of the North Sea. Three independent pieces of informations from all 7 TM channels were found with factor analysis: suspended matter concentration, atmospheric scattering and sea surface temperature. Near surface suspended matter concentrations may be detected within a factor of 2. For the required atmospheric correction the signal-to-noise ratio of the channels 5 and 7 has to be improved by averaging over 25 x 25 pixels. Thus TM allows to monitor aerosol optical depth and aerosol type over cloudfree water surfaces. Sea surface temperature is retrievable with an absolute accuracy of 1.0 K as long as radiosonde data are available for the correction of atmospheric effects, while relative temperature variations of 0.5 K are detectable. The patchiness of suspended matter and its relation to underwater topography was analysed with auto- and crosscorrelation: horizontal lengths, where the suspended matter concentration of single pixels are significantly correlated either with each another or with water depth, are < 800 m. (orig.).

Nutritional composition of suspended particulate matter in a tropical mangrove creek during a tidal cycle (Can Gio, Vietnam)

Science.gov (United States)

David, Frank; Marchand, Cyril; Taillardat, Pierre; Thành-Nho, Nguyễn; Meziane, Tarik

2018-01-01

Mangrove forests are highly productive ecosystems and mangrove-derived organic matter has generally been assumed to play a basal role in sustaining coastal food webs. However, the mechanisms of mangrove-derived organic matter utilisation by consumers are not fully understood. In this study, we were interested in hourly changes in the nutritional quality of suspended particulate matter (SPM) entering and departing a mangrove creek during a tidal cycle. We determined the fatty acid composition and δ13C stable isotope signature of SPM during a 26 h tidal cycle in a creek of the Can Gio Mangrove Biosphere Reserve (Southern Vietnam). Regarding fatty acids, the nutritional quality of SPM was low during most of the tidal cycle. However, it greatly increased during the first part of the strongest flood tide, occurring during daytime. The pulse of highly nutritive organic matter brought to the ecosystem was mostly composed of algal cells growing in specific shallow zones of the mangrove, that use nutrients and CO2 exported during the preceding ebb tide and originating from the mineralisation of mangrove-derived organic matter, as evidenced by their δ13C signatures. This study confirms that mangrove-derived carbon plays a basal role in sustaining trophic webs of mangrove tidal creeks, but that its nutritive value is greatly enhanced when a first step of mineralisation is achieved and CO2 is photosynthesised by algal cells.

Does SW Monsoon Influence Total Suspended Matter Flux into the Arabian Sea?

Digital Repository Service at National Institute of Oceanography (India)

Raghavan, B.R.; Chauhan, O.S.

Seasonal enhancement in the flux of total suspended matter (TSM) has been attributed to climatology of the SW monsoon (SWM) in time-series trap experiments conducted in the Arabian Sea. To determine the influence of climate on TSM flux, synoptic...

Sources and export of particle-borne organic matter during a monsoon flood in a catchment of northern Laos

Science.gov (United States)

Gourdin, E.; Huon, S.; Evrard, O.; Ribolzi, O.; Bariac, T.; Sengtaheuanghoung, O.; Ayrault, S.

2015-02-01

The yields of the tropical rivers of Southeast Asia supply large quantities of carbon to the ocean. The origin and dynamics of particulate organic matter were studied in the Houay Xon River catchment located in northern Laos during the first erosive flood of the rainy season in May 2012. This cultivated catchment is equipped with three successive gauging stations draining areas ranging between 0.2 and 11.6 km2 on the main stem of the permanent stream, and two additional stations draining 0.6 ha hillslopes. In addition, the sequential monitoring of rainwater, overland flow and suspended organic matter compositions was conducted at the 1 m2 plot scale during a storm. The composition of particulate organic matter (total organic carbon and total nitrogen concentrations, δ13C and δ15N) was determined for suspended sediment, soil surface (top 2 cm) and soil subsurface (gullies and riverbanks) samples collected in the catchment (n = 57, 65 and 11, respectively). Hydrograph separation of event water was achieved using water electric conductivity and δ18O measurements for rainfall, overland flow and river water base flow (n = 9, 30 and 57, respectively). The composition of particulate organic matter indicates that upstream suspended sediments mainly originated from cultivated soils labelled by their C3 vegetation cover (upland rice, fallow vegetation and teak plantations). In contrast, channel banks characterized by C4 vegetation (Napier grass) supplied significant quantities of sediment to the river during the flood rising stage at the upstream station as well as in downstream river sections. The highest runoff coefficient (11.7%), sediment specific yield (433 kg ha-1), total organic carbon specific yield (8.3 kg C ha-1) and overland flow contribution (78-100%) were found downstream of reforested areas planted with teaks. Swamps located along the main stream acted as sediment filters and controlled the composition of suspended organic matter. Total organic carbon

Analysis of Thematic Mapper data for studying the suspended matter distribution in the coastal area of the German Bight (North Sea)

Science.gov (United States)

Doerffer, R.; Fischer, J.; Stoessel, M.; Brockmann, C.; Grassl, H.

1989-01-01

Thematic Mapper data were analyzed with respect to its capability for mapping the complex structure and dynamics of suspended matter distribution in the coastal area of the German Bight (North Sea). Three independent pieces of information were found by factor analysis of all seven TM channels: suspended matter concentration, atmospheric scattering, and sea surface temperature. For the required atmospheric correction, the signal-to-noise ratios of Channels 5 and 7 have to be improved by averaging over 25 x 25 pixels, which also makes it possible to monitor the aerosol optical depth and aerosol type over cloud-free water surfaces. Near-surface suspended matter concentrations may be detected with an accuracy of factor less than 2 by using an algorithm derived from radiative transfer model calculation. The patchiness of suspended matter and its relation to underwater topography was analyzed with autocorrelation and cross-correlation.

Experimental study on kinetics oil oil-suspended particulate matter aggregation

International Nuclear Information System (INIS)

Sun, J.; Environment Canada, Ottawa, ON; Khelifa, A.; Wang, Z.; Brown, C.; Fieldhouse, B.; Yang, C.; Zheng, X.; Wong, S.; So, L.C.

2009-01-01

Past studies of oil spills have shown that oil suspended particulate matter aggregates (OSAs) play a role in enhancing the natural cleansing of oiled shorelines. OSAs result from aggregation between suspended oil droplets and suspended particulate matter (SPM) in aquatic environments. During this process, oil dispersion into the water column is significantly increased since the surface of the oil droplet is surrounded by sediment particles. In addition, the accelerated biodegradation of the oil can be attributed to the greater oil-water contact area. This study focused on the kinetic aspects of OSA formation, with particular reference to the time scale of this process and its significance to oil dispersion following oil spills in water. A laboratory study was conducted to measure the time scale of OSA formation and its variations with mixing conditions. A reciprocating shaker and various oil/sediment mixtures were used to prepare the OSAs. Standard reference material 1941b was used as the natural sediment mixed with Arabian medium crude and artificial seawater under various mixing energies. The sediment-to-oil ratio remained constant for all experiments. Gas chromatography-flame ionization detection (GC-FID) analysis was used to measure the total petroleum hydrocarbons (TPH) trapped in negatively buoyant OSAs. Results showed that the TPH in OSAs increased exponentially with shaking time and reached an equilibrium value within 3 hours. The equilibrium decreased from 3 hours to 1.3 hours when the shaking rate increased from 2.0 to 2.3 Hz. It was concluded that high mixing energy enhances OSA formation and shortens the time for OSA formation. 42 refs., 6 tabs., 5 figs

Experimental study on kinetics oil oil-suspended particulate matter aggregation

Energy Technology Data Exchange (ETDEWEB)

Sun, J. [Ocean Univ. of China, Qingdoa (China). Environmental Science and Engineering Inst.; Environment Canada, Ottawa, ON (Canada). Emergencies Science and Technology Section, Emergencies, Operational Analytical Laboratories and Research Support Division; Khelifa, A.; Wang, Z.; Brown, C.; Fieldhouse, B.; Yang, C. [Environment Canada, Ottawa, ON (Canada). Emergencies Science and Technology Section, Emergencies, Operational Analytical Laboratories and Research Support Division; Zheng, X. [Ocean Univ. of China, Qingdoa (China). Environmental Science and Engineering Inst.; Wong, S. [Ottawa Univ., ON (Canada). Dept. of Chemistry; So, L.C. [Waterloo Univ., ON (Canada). Faculty of Engineering

2009-07-01

Past studies of oil spills have shown that oil suspended particulate matter aggregates (OSAs) play a role in enhancing the natural cleansing of oiled shorelines. OSAs result from aggregation between suspended oil droplets and suspended particulate matter (SPM) in aquatic environments. During this process, oil dispersion into the water column is significantly increased since the surface of the oil droplet is surrounded by sediment particles. In addition, the accelerated biodegradation of the oil can be attributed to the greater oil-water contact area. This study focused on the kinetic aspects of OSA formation, with particular reference to the time scale of this process and its significance to oil dispersion following oil spills in water. A laboratory study was conducted to measure the time scale of OSA formation and its variations with mixing conditions. A reciprocating shaker and various oil/sediment mixtures were used to prepare the OSAs. Standard reference material 1941b was used as the natural sediment mixed with Arabian medium crude and artificial seawater under various mixing energies. The sediment-to-oil ratio remained constant for all experiments. Gas chromatography-flame ionization detection (GC-FID) analysis was used to measure the total petroleum hydrocarbons (TPH) trapped in negatively buoyant OSAs. Results showed that the TPH in OSAs increased exponentially with shaking time and reached an equilibrium value within 3 hours. The equilibrium decreased from 3 hours to 1.3 hours when the shaking rate increased from 2.0 to 2.3 Hz. It was concluded that high mixing energy enhances OSA formation and shortens the time for OSA formation. 42 refs., 6 tabs., 5 figs.

Application of in situ observations, high frequency radars, and ocean color, to study suspended matter, particulate carbon, and dissolved organic carbon fluxes in coastal waters of the Barents Sea - the NORDFLUX project

Science.gov (United States)

Stramska, Malgorzata; Yngve Børsheim, Knut; Białogrodzka, Jagoda; Cieszyńska, Agata; Ficek, Dariusz; Wereszka, Marzena

2016-04-01

There is still a limited knowledge about suspended and dissolved matter fluxes transported from coastal regions into the open sea regions in the Arctic. The land/sea interface is environmentally important and sensitive to climate change. Important biogeochemical material entering the oceans (including carbon) passes through this interface, but too little is known about the efficiency of this transport. Our goal in the NORDFLUX program is to improve quantitative understanding of the environmental feedbacks involved in these processes through an interdisciplinary study with innovative in situ observations. Completed work includes two in situ experiments in the Norwegian fiord (Porsangerfjorden) in the summers of 2014 and 2015. Experiments used research boat for collection of water samples and in situ bio-optical data, an autonomous glider, mooring with T S sensors, and a high frequency radar system. We have used these data to derive spatial maps of water temperature, salinity, surface currents, chlorophyll fluorescence, dissolved organic matter (DOM) fluorescence, and inherent optical properties (IOPs) of the water. The interpretation of these data in terms of suspended matter concentration and composition is possible by in situ 'calibrations' using water samples from discrete hydrographic stations. Total suspended matter (TSM), particulate carbon (POC and PIC), and dissolved organic carbon (DOC) concentrations together with measured water currents will allow us to estimate reservoirs and fluxes. Concentrations and fluxes will be related to physical conditions and meteorological data. An important aspect of this project is the work on regional ocean color algorithms. Global ocean color (OC) algorithms currently used by NASA do not perform sufficiently well in coastal Case 2 waters. Our data sets will allow us to derive such local algorithms. We will then use these algorithms for interpretation of OC data in terms of TSM concentrations and composition and DOC. After

Nature and sources of suspended particulate organic matter in a tropical estuary during the monsoon and pre-monsoon: Insights from stable isotopes (delta 13C POC, delta 15 N TPN) and carbohydrate signature compounds

Digital Repository Service at National Institute of Oceanography (India)

Khodse, V.B.; Bhosle, N.B.

zooplankton, and then known aliquots (0.25 to 1.5 L) were filtered through pre-combusted (450 °C, 4h) 47 mm GF/F filter papers (0.7 µm, Whatman) for the measurements of suspended particulate matter (SPM), particulate organic carbon (POC), δ13CPOC, δ15NTPN... analysis. 2.3. Determination of bulk parameters and stable isotopes GF/F (0.7 µm, 47 mm) filter containing particulate matter was washed with UV-Milli-Q- water to remove salt and the filter was dried at 40 °C for 24 h. Filter was cooled and weighed...

Adaption of the suspension behavior of suspended matter in natural water

International Nuclear Information System (INIS)

Hattenbach, K.; Schreier, H.H.; Zimmermann, H.U.

1980-01-01

The particle size distribution of an artificial tracer is adapted to that of suspended matter in natural water. Therefore the material of a tracer was divided into fractions and afterwards mixed according to computed proportions. The determination of particle size distribution was carried out using a sedimentation balance. For calculation of the distribution curve a special mathematical function was assumed. (orig.) [de

Thematic mapper research in the earth sciences: Small scale patches of suspended matter and phytoplankton in the Elbe River Estuary, German Bight and Tidal Flats

Science.gov (United States)

Grassl, H.; Doerffer, R.; Fischer, J.; Brockmann, C.; Stoessel, M.

1987-01-01

A Thematic Mapper (TM) field experiment was followed by a data analysis to determine TM capabilities for analysis of suspended matter and phytoplankton. Factor analysis showed that suspended matter concentration, atmospheric scattering, and sea surface temperature can be retrieved as independent factors which determine the variation in the TM data over water areas. Spectral channels in the near infrared open the possibility of determining the Angstrom exponent better than for the coastal zone color scanner. The suspended matter distribution may then be calculated by the absolute radiance of channel 2 or 3 or the ratio of both. There is no indication of whether separation of chlorophyll is possible. The distribution of suspended matter and sea surface temperature can be observed with the expected fine structure. A good correlation between water depth and suspended matter distribution as found from ship data can now be analyzed for an entire area by the synoptic view of the TM scenes.

Variations in some environmental characteristics including C and N stable isotopic composition of suspended organic matter in the Mandovi estuary.

Science.gov (United States)

Maya, M V; Soares, Melena A; Agnihotri, Rajesh; Pratihary, A K; Karapurkar, Supriya; Naik, Hema; Naqvi, S W A

2011-04-01

Chemical and isotopic (δ13C and δ15N) investigation of the Mandovi estuary along the Indian west coast affected strongly by the seasonal monsoon cycle was carried out. The Mandovi estuary is a major waterway for Goa and extensively used for transportation of iron and manganese ore. In addition, with large population centers as well as agricultural fields located on its shores, the estuary is assumed to have been influenced by human activities. Measurements of chemical and isotopic parameters made in the lower part of the estuary during the southwest (SW) monsoon and post-monsoon seasons reveal distinct changes, and it is observed that despite considerable enrichment of macronutrients during the SW monsoon, productivity of the estuary (phytoplankton biomass), as inferred from the chlorophyll-a content, is not as high as expected. This is due to occurrences of high turbidity and cloud cover that limits photosynthetic productivity. The isotopic characterization (C and N isotopes) of suspended organic matter produced/transported during the monsoon and post-monsoon seasons of year 2007 provides a baseline dataset for future isotopic studies in such type of tropical estuaries.

Distribution of suspended particulate matter in the waters of eastern continental margin of India

Digital Repository Service at National Institute of Oceanography (India)

Rao, Ch.M.

Distribution of total suspended matter (TSM) in surface and near bottom (approximately 5 m above sea bed) waters reveals a wide variation in concentration and composition. TSM varies from 0.05 to 122 mg.l/1 in surface waters, and from 0.25 top 231...

Association of uranium with colloidal and suspended particulate matter in Arabian sea near the west coast of Maharashtra (India)

International Nuclear Information System (INIS)

Singhal, R.K.; Joshi, S.N.; Hegde, A.G.

2004-01-01

Association of natural uranium in seawater with colloidal and suspended-particulate matter was determined. The separation of suspended particulate material (>0.45 ) and colloidal fraction (as dissolved fractions) in seawater were done by suction and ultra filtration techniques. Seawater samples were collected at 1 km away from the shore and subjected to sequential fractionation in nine stages ranging from 2.7 μm to 1.1 nm. Suspended particulate matter were separated in three different size groups namely >2.7 μm, 0.45 μm and 0.22 μm by suction filtration using cellulose acetate and nitrate membranes filters. To concentrate the solution with colloidal particles <0.22 μm-1.1 nm (0.5 k Nominal Molecular Weight cut-off Limit (NMWL), the solution obtained from filtration through <0.22 μm was passed through stirred ultra-filtration cell. The pH and conductivity at different stages of fractionation (dissolved) showed minor variations. The concentration of uranium was measured in suspended and dissolved fractions by using a pulsed nitrogen laser at 337.1 nm. In order to evaluate the role of mineral colloids in various stages of filtration, concentration of calcium, magnesium, potassium were measured by using ion chromatography and atomic absorption spectrometry. The clay mineral at seawater pH (approximately 8) behave as negative ions and provides binding site for the positively charge species of uranium. Among the dissolved fraction, the maximum concentrations of colloidal uranium was observed about 4 times higher than that compared to average concentration of 6.93 ± 3.10 ppb in other fractions. In the case of suspended particulate matter, the concentration of uranium was below detection limits (<1 ppb). The maximum concentration of Ca, Mg and K in the dissolved fraction were in the <1.1 nm fraction, while for suspended particulate matter, the concentration of Ca, Mg and K decreased with the decrease in size and it is highest in the fraction of 0.22 -0.45 μm.(author)

Soil organic matter

International Nuclear Information System (INIS)

1976-01-01

The nature, content and behaviour of the organic matter, or humus, in soil are factors of fundamental importance for soil productivity and the development of optimum conditions for growth of crops under diverse temperate, tropical and arid climatic conditions. In the recent symposium on soil organic matter studies - as in the two preceding ones in 1963 and 1969 - due consideration was given to studies involving the use of radioactive and stable isotopes. However, the latest symposium was a departure from previous efforts in that non-isotopic approaches to research on soil organic matter were included. A number of papers dealt with the behaviour and functions of organic matter and suggested improved management practices, the use of which would contribute to increasing agricultural production. Other papers discussed the turnover of plant residues, the release of plant nutrients through the biodegradation of organic compounds, the nitrogen economy and the dynamics of transformation of organic forms of nitrogen. In addition, consideration was given to studies on the biochemical transformation of organic matter, characterization of humic acids, carbon-14 dating and the development of modern techniques and their impact on soil organic matter research

A Novel Type of Oil—generating Organic Matter —Crystal—enclosed Organic Matter

Institute of Scientific and Technical Information of China (English)

周中毅; 裴存民; 等

1992-01-01

The comparative study of organic matter in carbonate rocks and argillaceous rocks from the same horizon indicates that the organic thermal maturities of carbonate rocks are much lower than those of argillaceous rocks .Ana extensive analysis of extracted and inclused organic matter from the same sample shows that inclused organic matter is different from extracted organic matter,and the thermal maturity of the former is usually lower than that of the latter in terms of biomarker structural parameters.It seems that carbonate mineras could preserve organic matter and retard organic maturation.The inclused organic matter,abundant in most carbonate rocks,will be released from minerals and transformed into oil and gas during the high-thermal maturity stage.

Seasonal variations of total suspended matter (TSM) in the Gulf of Khambhat, west coast of India

Digital Repository Service at National Institute of Oceanography (India)

Misra, A.; ManiMurali, R.; Sukumaran, S.; Vethamony, P.

Total Suspended Matter (TSM)is an important parameter for determining the water quality in coastal regions as it is responsible for the reduction in the light available to the aquatic vegetation which subsequently alters the health and quality...

Soil organic matter studies

International Nuclear Information System (INIS)

1977-01-01

A total of 77 papers were presented and discussed during this symposium, 37 are included in this Volume II. The topics covered in this volume include: biochemical transformation of organic matter in soils; bitumens in soil organic matter; characterization of humic acids; carbon dating of organic matter in soils; use of modern techniques in soil organic matter research; use of municipal sludge with special reference to heavy metals constituents, soil nitrogen, and physical and chemical properties of soils; relationship of soil organic matter and plant metabolism; interaction between agrochemicals and organic matter; and peat. Separate entries have been prepared for those 20 papers which discuss the use of nuclear techniques in these studies

Formation of Chromophoric Dissolved Organic Matter by Bacterial Degradation of Phytoplankton-Derived Aggregates

Directory of Open Access Journals (Sweden)

Joanna D. Kinsey

2018-01-01

Full Text Available Organic matter produced and released by phytoplankton during growth is processed by heterotrophic bacterial communities that transform dissolved organic matter into biomass and recycle inorganic nutrients, fueling microbial food web interactions. Bacterial transformation of phytoplankton-derived organic matter also plays a poorly known role in the formation of chromophoric dissolved organic matter (CDOM which is ubiquitous in the ocean. Despite the importance of organic matter cycling, growth of phytoplankton and activities of heterotrophic bacterial communities are rarely measured in concert. To investigate CDOM formation mediated by microbial processing of phytoplankton-derived aggregates, we conducted growth experiments with non-axenic monocultures of three diatoms (Skeletonema grethae, Leptocylindrus hargravesii, Coscinodiscus sp. and one haptophyte (Phaeocystis globosa. Phytoplankton biomass, carbon concentrations, CDOM and base-extracted particulate organic matter (BEPOM fluorescence, along with bacterial abundance and hydrolytic enzyme activities (α-glucosidase, β-glucosidase, leucine-aminopeptidase were measured during exponential growth and stationary phase (~3–6 weeks and following 6 weeks of degradation. Incubations were performed in rotating glass bottles to keep cells suspended, promoting cell coagulation and, thus, formation of macroscopic aggregates (marine snow, more similar to surface ocean processes. Maximum carbon concentrations, enzyme activities, and BEPOM fluorescence occurred during stationary phase. Net DOC concentrations (0.19–0.46 mg C L−1 increased on the same order as open ocean concentrations. CDOM fluorescence was dominated by protein-like signals that increased throughout growth and degradation becoming increasingly humic-like, implying the production of more complex molecules from planktonic-precursors mediated by microbial processing. Our experimental results suggest that at least a portion of open

Amino sugars in suspended particulate matter from the Bay of ...

Indian Academy of Sciences (India)

Amino sugars (AS) are important constituents of organic matter. However ... about the molecular level characterization, distri- bution and ... tion about the dynamics, nutritive value, nature and degradation state of AS containing organic matter. 2. Material ..... carbohydrates and amino acids; Marine Chemistry 96. 155–184.

Optical Algorithms at Satellite Wavelengths for Total Suspended Matter in Tropical Coastal Waters

OpenAIRE

Ouillon, Sylvain; Douillet, Pascal; Petrenko, Anne; Neveux, Jacques; Dupouy, C?cile; Froidefond, Jean-Marie; Andr?fou?t, Serge; Mu?oz-Caravaca, Alain

2008-01-01

Is it possible to derive accurately Total Suspended Matter concentration or its proxy, turbidity, from remote sensing data in tropical coastal lagoon waters? To investigate this question, hyperspectral remote sensing reflectance, turbidity and chlorophyll pigment concentration were measured in three coral reef lagoons. The three sites enabled us to get data over very diverse environments: oligotrophic and sediment-poor waters in the southwest lagoon of New Caledonia, eutrophic waters in the C...

Organic matter and soil moisture content and double cropping with organic matter sourceplants

OpenAIRE

John Bako Baon; Aris Wibawa

2005-01-01

Double cropping of coffee with organic matter source plants is thought to increase organic matter content of soil. This study examined the effect of double cropping of coffee and organic matter source plants on soil organic matter content and yield of coffee plants. Arabica coffee trees in Andungsari Experimental Station (Bondowoso district), 1400 m asl. and climate type C; and Robusta coffee trees in Sumberasin Experimental Station (Malang district), 550 m asl. and climate type C, were used ...

Delineating the relationship between chromophoric dissolved organic matter (CDOM) variability and biogeochemical parameters in a shallow continental shelf

OpenAIRE

Sourav Das; Sugata Hazra; Aneesh A. Lotlikar; Isha Das; Sandip Giri; Abhra Chanda; Anirban Akhand; Sourav Maity; T. Srinivasa Kumar

2016-01-01

Absorption coefficient of chromophoric dissolved organic matter (CDOM) at 440 nm [aCDOM (440)], sea surface salinity (SSS), total suspended matter (TSM) and chlorophyll-a (chl-a) were measured during October, 2014 to March, 2015 in the shallow continental shelf waters of the Hugli Estuary, adjacent to West Bengal coast, India. The primary objective of the study was to characterize the relationship between aCDOM (440) and the above mentioned biogeochemical parameters. Upon analyzing the result...

Floc size and aspects of flocculation processes of suspended particulate matter in the North Sea area

NARCIS (Netherlands)

Chen, S.

1995-01-01

Investigations on the size of suspended particulate matter in the North Sea and two adjacent estuaries were carried out using an in situ technique: image analysis of photographs from an underwater camera system. The results obtained from such an in situ method gave a new knowledge on the size

Feasibility of using acoustic velocity meters for estimating highly organic suspended-solids concentrations in streams

Science.gov (United States)

Patino, Eduardo

1996-01-01

A field experiment was conducted at the Levee 4 canal site below control structure G-88 in the Everglades agricultural area in northwestern Broward County, Florida, to study the relation of acoustic attenuation to suspended-solids concentrations. Acoustic velocity meter and temperature data were obtained with concurrent water samples analyzed for suspended-solids concentrations. Two separate acoustic velocity meter frequencies were used, 200 and 500 kilohertz, to determine the sensitivity of acoustic attenuation to frequency for the measured suspended-solids concentration range. Suspended-solids concentrations for water samples collected at the Levee 4 canal site from July 1993 to September 1994 ranged from 22 to 1,058 milligrams per liter, and organic content ranged from about 30 to 93 percent. Regression analyses showed that attenuation data from the acoustic velocity meter (automatic gain control) and temperature data alone do not provide enough information to adequately describe the concentrations of suspended solids. However, if velocity is also included as one of the independent variables in the regression model, a satisfactory correlation can be obtained. Thus, it is feasible to use acoustic velocity meter instrumentation to estimate suspended-solids concentrations in streams, even when suspended solids are primarily composed of organic material. Using the most comprehensive data set available for the study (500 kiloherz data), the best fit regression model produces a standard error of 69.7 milligrams per liter, with actual errors ranging from 2 to 128 milligrams per liter. Both acoustic velocity meter transmission frequencies of 200 and 500 hilohertz produced similar results, suggesting that transducers of either frequency could be used to collect attenuation data at the study site. Results indicate that calibration will be required for each acoustic velocity meter system to the unique suspended-solids regime existing at each site. More robust solutions may

Observations of a narrow zone of high suspended particulate matter (SPM) concentrations along the Dutch coast

NARCIS (Netherlands)

van der Hout, C.M.; Gerkema, T.; Nauw, J.J.; Ridderinkhof, H.

2015-01-01

The objective of the study described in this paper is to localize the transport path of suspended particulate matter (SPM) in the Dutch coastal zone in the southern North Sea. It is known that a large mass of SPM is transported northward from the Strait of Dover, which is however mostly hidden from

Study of seasonal dynamics of sedimentation evacuation of suspended matter, nutrients and pollutants from the surface water layer of the Black Sea during 1992-1994

International Nuclear Information System (INIS)

Gulin, S.B.; Polikarpov, G.G.; Egorov, V.N.; Krivenko, O.V.; Stokozov, N.A.; Zherko, N.V.

1995-01-01

A series of regular measurements of sedimentation evacuation of suspended matter, nutrients (carbon, nitrogen) and pollutants (mercury, polychlorided biphenyls) from the surface water layer was carried out with 1-2 month interval between the measurements using 234 Th in the region of western cyclonic circulation of the Black Sea. It allowed to estimate the seasonal dynamics and to obtain average annual values of dientrophication and sedimentational self-purification of the euphotic zone of the Western part of the Black Sea. The parallel measurements of the rates of sedimentation evacuation of suspended organic nitrogen from the euphotic zone, which were performed using 234 Th and determining the so called products of phitoplankton by the absorption of 15 N traced nitrates and ammonium, give practically identical results. 19 refs.; 5 figs

Organic matters: investigating the sources, transport, and fate of organic matter in Fanno Creek, Oregon

Science.gov (United States)

Sobieszczyk, Steven; Keith, Mackenzie K.; Goldman, Jami H.; Rounds, Stewart A.

2015-01-01

The term organic matter refers to the remnants of all living material. This can include fallen leaves, yard waste, animal waste, downed timber, or the remains of any other plant and animal life. Organic matter is abundant both on land and in water. Investigating organic matter is necessary for understanding the fate and transport of carbon (a major constituent of organic matter).

Trace elements in suspended particulate matter and liquid fraction of the Arno River waters

International Nuclear Information System (INIS)

Capannesi, G.; Cecchi, A.; Mando, P.A.

1984-01-01

The concentrations of 46 elements along the course of the Arno River (Tuscany, Italy) have been determined by means of Instrumental Neutron Activation Analysis. Both suspended particulate matter and liquid fraction have been investigated. No chemical treatment has been performed on the samples, either before or after irradiation. Anticoincidence techniques have been employed in the γ spectroscopy. Results are briefly discussed also from a methodological point of view. 4 references, 16 figures, 2 tables

Quantifying uncertainty in measurement of mercury in suspended particulate matter by cold vapor technique using atomic absorption spectrometry with hydride generator.

Science.gov (United States)

Singh, Nahar; Ahuja, Tarushee; Ojha, Vijay Narain; Soni, Daya; Tripathy, S Swarupa; Leito, Ivo

2013-01-01

As a result of rapid industrialization several chemical forms of organic and inorganic mercury are constantly introduced to the environment and affect humans and animals directly. All forms of mercury have toxic effects; therefore accurate measurement of mercury is of prime importance especially in suspended particulate matter (SPM) collected through high volume sampler (HVS). In the quantification of mercury in SPM samples several steps are involved from sampling to final result. The quality, reliability and confidence level of the analyzed data depends upon the measurement uncertainty of the whole process. Evaluation of measurement uncertainty of results is one of the requirements of the standard ISO/IEC 17025:2005 (European Standard EN IS/ISO/IEC 17025:2005, issue1:1-28, 2006). In the presented study the uncertainty estimation in mercury determination in suspended particulate matter (SPM) has been carried out using cold vapor Atomic Absorption Spectrometer-Hydride Generator (AAS-HG) technique followed by wet chemical digestion process. For the calculation of uncertainty, we have considered many general potential sources of uncertainty. After the analysis of data of seven diverse sites of Delhi, it has been concluded that the mercury concentration varies from 1.59 ± 0.37 to 14.5 ± 2.9 ng/m(3) with 95% confidence level (k = 2).

Principal sources and dispersal patterns of suspended particulate matter in nearshore surface waters of the northeast Pacific Ocean and the Hawaiian Islands

Science.gov (United States)

Carlson, P. R. (Principal Investigator); Conomos, T. J.; Janda, R. J.; Peterson, D. H.

1973-01-01

The author has identified the following significant results. ERTS-1 multispectral scanner imagery of the nearshore surface waters of the Northeast Pacific Ocean is proving to be a useful tool for determining source and dispersal of suspended particulate matter. The principal sources of the turbid water, seen best on the green and red bands, are river and stream effluents and actively eroding coastlines; secondary sources are waste effluents and production of planktonic organisms, but these may sometimes be masked by the very turbid plumes of suspended sediment being discharged into the nearshore zone during times of high river discharge. The configuration and distribution of the plumes of turbid water also can be used to infer near-surface current directions. Comparison of imagery of the nearshore water off the northern California coast from October 1972 and January 1973 shows a reversal of the near-surface currents, from predominantly south-setting in the fall (California Current) to north-setting in the winter (Davidson Current).

Sources and fate of organic matter in suspended and bottom sediments of the Mandovi and Zuari estuaries, Western India

Digital Repository Service at National Institute of Oceanography (India)

Shynu, R; Rao, V.P.; Sarma, V.V.S.S.; Kessarkar, P.M.; ManiMurali, R

in western India during wet and dry seasons, to characterize the sources of organic matter (OM) in these systems. Unlike major rivers, SPM concentrations increase seaward with a general trend of decreasing particulate organic carbon (POC) in these rivers...

International Odra project (IOP) 'Interdisciplinary German Polish studies on the behaviour of pollutants in the Oder system'. Sub project 4: the state of suspended particulate matter in the Odra River system. Final report

Energy Technology Data Exchange (ETDEWEB)

Henning, K.H.; Damke, H.; Kasbohm, J.; Puff, T.; Breitenbach, E.; Theel, O.; Kiessling, A.

2001-05-20

The purpose of the present project was to characterise the pollutant freight of suspended matter and suspended-matter-borne sediments in the Oder river system on the basis of large samples drawn at selected sampling sites. One of the major goals was to assess and draw up a balance of the transport regime of suspended matter between the compartments water, suspended matter and sediments. Special attention was given to the composition and structure of suspended matter as well as to the distribution of trace elements in the various components. Furthermore, the study was intended to provide ecology-related information on the basis of selected biogenic components. Statements on the time course of pollution of estuarine waters and the Baltic Sea by way of the Oder can be derived from a characterisation of current fluviatile solids (suspended matter and suspended-matter-borne sediments) and determination of their quantitative proportions. The following research strategy was derived from these goals: for a characterisation of suspended matter in terms of composition, structure and biogenic origin it is necessary to determine the concentration of suspended matter, its granulometric composition, carbon and sulphur content, biogenic opal content, mineral content, phase composition, metal content, structure of suspended flakes and association of diatoms in the suspended flakes and on the periphyton. [German] Das Vorhaben ist darauf ausgerichtet, den Belastungszustand der Schwebstoffe und schwebstoffbuertigen Sedimente im Oderflusssystem anhand von Grossproben ausgewaehlter Probenahmeorte zu charakterisieren. Ein wesentliches Ziel ist die Beurteilung des Transportregimes der Schwebstoffe zwischen den Kompartimenten Wasser, Schwebstoff und Sediment sowie seine Bilanzierung. Dabei gilt die besondere Aufmerksamkeit der Zusammensetzung und der Struktur der Schwebstoffe sowie die Spurenelementspeziation an die unterschiedlichen Bestandteile. Weiterhin werden oekologische Aussagen

Effect of influent aeration on removal of organic matter from coffee processing wastewater in constructed wetlands.

Science.gov (United States)

Rossmann, Maike; Matos, Antonio Teixeira; Abreu, Edgar Carneiro; Silva, Fabyano Fonseca; Borges, Alisson Carraro

2013-10-15

The aim of the present study was to evaluate the influence of aeration and vegetation on the removal of organic matter in coffee processing wastewater (CPW) treated in 4 constructed wetlands (CWs), characterized as follows: (i) ryegrass (Lolium multiflorum) cultivated system operating with an aerated influent; (ii) non-cultivated system operating with an aerated influent, (iii) ryegrass cultivated system operating with a non-aerated influent; and (iv) non-cultivated system operating with a non-aerated influent. The lowest average chemical oxygen demand (COD), biochemical oxygen demand (BOD) and total suspended solids (TSS) removal efficiencies of 87, 84 and 73%, respectively, were obtained in the ryegrass cultivated system operating with a non-aerated influent. However, ryegrass cultivation did not influence the removal efficiency of organic matter. Artificial aeration of the CPW, prior to its injection in the CW, did not improve the removal efficiencies of organic matter. On other hand it did contribute to increase the instantaneous rate at which the maximum COD removal efficiency was reached. Although aeration did not result in greater organic matter removal efficiencies, it is important to consider the benefits of aeration on the removal of the other compounds. Copyright © 2013 Elsevier Ltd. All rights reserved.

Biogeochemical characteristics of suspended particulate matter in deep chlorophyll maximum layers in the southern East China Sea

Science.gov (United States)

Liu, Qianqian; Kandasamy, Selvaraj; Lin, Baozhi; Wang, Huawei; Chen, Chen-Tung Arthur

2018-04-01

Continental shelves and marginal seas are key sites of particulate organic matter (POM) production, remineralization and sequestration, playing an important role in the global carbon cycle. Elemental and stable isotopic compositions of organic carbon and nitrogen are thus frequently used to characterize and distinguish POM and its sources in suspended particles and surface sediments in the marginal seas. Here we investigated suspended particulate matter (SPM) collected around deep chlorophyll maximum (DCM) layers in the southern East China Sea for particulate organic carbon and nitrogen (POC and PN) contents and their isotopic compositions (δ13CPOC and δ15NPN) to understand provenance and dynamics of POM. Hydrographic parameters (temperature, salinity and turbidity) indicated that the study area was weakly influenced by freshwater derived from the Yangtze River during summer 2013. Elemental and isotopic results showed a large variation in δ13CPOC (-25.8 to -18.2 ‰) and δ15NPN (3.8 to 8.0 ‰), but a narrow molar C / N ratio (4.1-6.3) and low POC / Chl a ratio ( < 200 g g-1) in POM, and indicated that the POM in DCM layers was newly produced by phytoplankton. In addition to temperature effects, the range and distribution of δ13CPOC were controlled by variations in primary productivity and phytoplankton species composition; the former explained ˜ 70 % of the variability in δ13CPOC. However, the variation in δ15NPN was controlled by the nutrient status and δ15NNO3- in seawater, as indicated by similar spatial distribution between δ15NPN and the current pattern and water masses in the East China Sea; although interpretations of δ15NPN data should be verified with the nutrient data in future studies. Furthermore, the POM investigated was weakly influenced by the terrestrial OM supplied by the Yangtze River during summer 2013 due to the reduced sediment supply by the Yangtze River and north-eastward transport of riverine particles to the northern East China

Seasonal changes in suspended sediment load in the Gauthami-Godavari Estuary

Digital Repository Service at National Institute of Oceanography (India)

Reddy, N.P.C.; Rao, B.P.; Rao, K.M.; Rao, V.S.

Studies carried out on suspended matter characteristics of the the Gautami Godavari Estuary revealed that the concentration of suspended matter (CSM) during southwest monsoon influenced mainly by the increased run off at both Neelarevu and Vrudha...

Riverine transport of terrestrial organic matter to the North Catalan margin, NW Mediterranean Sea

Science.gov (United States)

Sanchez-Vidal, Anna; Higueras, Marina; Martí, Eugènia; Liquete, Camino; Calafat, Antoni; Kerhervé, Philippe; Canals, Miquel

2013-11-01

found that water reservoirs along the rivers act as traps for terrestrial organic matter, reducing its delivery and ultimate burial into marine sediments. River hydrology also affects the quality of organic matter that reaches the coastal zone (both in terms of C and N) by shifting the relative weight of the various sources of terrestrial organic matter. During low river discharge (i.e., in summer and early autumn) the main contributor to the organic matter pool is mostly associated with freshwater primary producers, whereas with relatively high water flows (i.e., in winter and spring) the main contributor is associated with erosion and release of soil organic matter. Furthermore, the impact of waste water treatment plants into the studied rivers results in the alteration of the isotopic signal of suspended N. The three studied rivers play a major role in transporting terrestrial organic matter to the North Catalan margin, but the fraction that is exported to the deep margin by high-energy episodic hydrodynamic events, such as large coastal storms, has a minor importance.

Polybrominated diphenyl ethers in influents, suspended particulate matter, sediments, sewage treatment plant and effluents and biota from the Netherlands

NARCIS (Netherlands)

Boer, de J.; Wester, P.G.; Horst, van der A.; Leonards, P.E.G.

2003-01-01

Polybrominated diphenyl ethers (PBDEs) have been determined in 133 samples of suspended particulate matter (SPM), sediments, sewage treatment plant (STP) influents and effluents, fish and mussels from various locations in The Netherlands, as a part of a large Dutch national study on estrogenic

Flexible suspended gate organic thin-film transistors for ultra-sensitive pressure detection

Science.gov (United States)

Zang, Yaping; Zhang, Fengjiao; Huang, Dazhen; Gao, Xike; di, Chong-An; Zhu, Daoben

2015-03-01

The utilization of organic devices as pressure-sensing elements in artificial intelligence and healthcare applications represents a fascinating opportunity for the next-generation electronic products. To satisfy the critical requirements of these promising applications, the low-cost construction of large-area ultra-sensitive organic pressure devices with outstanding flexibility is highly desired. Here we present flexible suspended gate organic thin-film transistors (SGOTFTs) as a model platform that enables ultra-sensitive pressure detection. More importantly, the unique device geometry of SGOTFTs allows the fine-tuning of their sensitivity by the suspended gate. An unprecedented sensitivity of 192 kPa-1, a low limit-of-detection pressure of <0.5 Pa and a short response time of 10 ms were successfully realized, allowing the real-time detection of acoustic waves. These excellent sensing properties of SGOTFTs, together with their advantages of facile large-area fabrication and versatility in detecting various pressure signals, make SGOTFTs a powerful strategy for spatial pressure mapping in practical applications.

Investigation of the suspended particulate matter in the Asian region for seven years

International Nuclear Information System (INIS)

Harasawa, Susumu

1999-01-01

Activities of the workshops for the investigation of environmental materials by NAA (Neutron Activation Analysis) methods during 1992 to 1997 held in Jakarta are briefly reported. Detail of selection of the theme (investigation of the suspended particulate matter in the Asian region by NAA), the results of the inter-comparison for the analysis using NIES No. 8 reference standard samples (vehicle exhaust particulate) are presented. In conclusion, systematically accumulated data on the environmental substances and their time variations measured and analyzed by INAA (Instrumental Neutron Activation Analysis) method give useful information on pollution problems and air movement in the Asia region. (S. Ohno)

Investigation of the suspended particulate matter in the Asian region for seven years

Energy Technology Data Exchange (ETDEWEB)

Harasawa, Susumu [Institute for Atomic Energy, Rikkyo Univ., Yokosuka, Kanagawa (Japan)

1999-10-01

Activities of the workshops for the investigation of environmental materials by NAA (Neutron Activation Analysis) methods during 1992 to 1997 held in Jakarta are briefly reported. Detail of selection of the theme (investigation of the suspended particulate matter in the Asian region by NAA), the results of the inter-comparison for the analysis using NIES No. 8 reference standard samples (vehicle exhaust particulate) are presented. In conclusion, systematically accumulated data on the environmental substances and their time variations measured and analyzed by INAA (Instrumental Neutron Activation Analysis) method give useful information on pollution problems and air movement in the Asia region. (S. Ohno)

Distribution of tritium in estuarine waters: the role of organic matter

International Nuclear Information System (INIS)

Turner, Andrew; Millward, Geoffrey E.; Stemp, Martin

2009-01-01

Tritium is an important environmental radionuclide whose reactivity with ligands and solids in aquatic systems is assumed to be limited. We studied the fractionation and sorption of tritium (added as tritiated water) in river water and seawater, and found that its distribution appears to be influenced by its affinity for organic matter. Tritium rapidly equilibrates with dissolved organic ligands that are retained by a reverse-phase C18 column, and with suspended sediment particles. Significantly, a measurable fraction of sorbed tritium associates with proteinaceous material that is potentially available to sediment-feeding organisms. These characteristics have not been reported previously and cannot be accounted for solely by isotopic exchange with hydrogen. Nevertheless, they are in qualitative agreement with available measurements of tritium in estuarine and coastal waters where its principal discharge is as tritiated water. Further research into the estuarine biogeochemical behaviour of tritium is required and radiological distribution coefficients and concentration factors that are assumed for this radionuclide may require reconsideration.

Distribution of tritium in estuarine waters: the role of organic matter

Energy Technology Data Exchange (ETDEWEB)

Turner, Andrew [Consolidated Radio-isotope Facility, School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)], E-mail: aturner@plymouth.ac.uk; Millward, Geoffrey E.; Stemp, Martin [Consolidated Radio-isotope Facility, School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL4 8AA (United Kingdom)

2009-10-15

Tritium is an important environmental radionuclide whose reactivity with ligands and solids in aquatic systems is assumed to be limited. We studied the fractionation and sorption of tritium (added as tritiated water) in river water and seawater, and found that its distribution appears to be influenced by its affinity for organic matter. Tritium rapidly equilibrates with dissolved organic ligands that are retained by a reverse-phase C18 column, and with suspended sediment particles. Significantly, a measurable fraction of sorbed tritium associates with proteinaceous material that is potentially available to sediment-feeding organisms. These characteristics have not been reported previously and cannot be accounted for solely by isotopic exchange with hydrogen. Nevertheless, they are in qualitative agreement with available measurements of tritium in estuarine and coastal waters where its principal discharge is as tritiated water. Further research into the estuarine biogeochemical behaviour of tritium is required and radiological distribution coefficients and concentration factors that are assumed for this radionuclide may require reconsideration.

Impact of sound attenuation by suspended sediment on ADCP backscatter calibrations

NARCIS (Netherlands)

Sassi, M.G.; Hoitink, A.J.F.; Vermeulen, B.

2012-01-01

Although designed for velocity measurements, acoustic Doppler current profilers (ADCPs) are widely being used to monitor suspended particulate matter in rivers and in marine environments. To quantify mass concentrations of suspended matter, ADCP backscatter is generally calibrated with in situ

Chlor-alkali industrial contamination and riverine transport of mercury: Distribution and partitioning of mercury between water, suspended matter, and bottom sediment of the Thur River, France

International Nuclear Information System (INIS)

Hissler, Christophe; Probst, Jean-Luc

2006-01-01

Total dissolved and total particulate Hg mass balances were estimated during one hydrological period (July 2001-June 2002) in the Thur River basin, which is heavily polluted by chlor-alkali industrial activity. The seasonal variations of the Hg dynamics in the aquatic environment were assessed using total Hg concentrations in bottom sediment and suspended matter, and total and reactive dissolved Hg concentrations in the water. The impact of the chlor-alkali plant (CAP) remains the largest concern for Hg contamination of this river system. Upstream from the CAP, the Hg partitioning between dissolved and particulate phases was principally controlled by the dissolved fraction due to snow melting during spring high flow, while during low flow, Hg was primarily adsorbed onto particulates. Downstream from the CAP, the Hg partitioning is controlled by the concentration of dissolved organic and inorganic ligands and by the total suspended sediment (TSS) concentrations. Nevertheless, the particulate fluxes were five times higher than the dissolved ones. Most of the total annual flux of Hg supplied by the CAP to the river is transported to the outlet of the catchment (total Hg flux: 70 μg m -2 a -1 ). Downstream from the CAP, the bottom sediment, mainly composed of coarse sediment (>63 μm) and depleted in organic matter, has a weak capacity to trap Hg in the river channel and the stock of Hg is low (4 mg m -2 ) showing that the residence time of Hg in this river is short

Suspended sediment concentration and optical property observations of mixed-turbidity, coastal waters through multispectral ocean color inversion

Science.gov (United States)

Multispectral satellite ocean color data from high-turbidity areas of the coastal ocean contain information about the surface concentrations and optical properties of suspended sediments and colored dissolved organic matter (CDOM). Empirical and semi-analytical inversion algorit...

Mercury and Dissolved Organic Matter Dynamics During Snowmelt in the Upper Provo River, Utah, USA

Science.gov (United States)

Packer, B. N.; Carling, G. T.; Nelson, S.; Aanderud, Z.; Shepherd Barkdull, N.; Gabor, R. S.

2017-12-01

Mercury (Hg) is deposited to mountains by atmospheric deposition and mobilized during snowmelt runoff, leading to Hg contamination in otherwise pristine watersheds. Mercury is typically transported with dissolved organic matter (DOM) from soils to streams and lakes. This study focused on Hg and DOM dynamics in the snowmelt-dominated upper Provo River watershed, northern Utah, USA. We sampled Hg, dissolved organic carbon (DOC) concentrations, and DOM fluorescence in river water, snowpack, and ephemeral streams over four years from 2014-2017 to investigate Hg transport mechanisms. During the snowmelt season (April through June), Hg concentrations typically increased from 1 to 8 ng/L showing a strong positive correlation with DOC. The dissolved Hg fraction was dominant in the river, averaging 75% of total Hg concentrations, suggesting that DOC is more important for transport than suspended particulate matter. Ephemeral channels, which represent shallow flow paths with strong interactions with soils, had the highest Hg (>10 ng/L) and DOC (>10 mg/L) concentrations, suggesting a soil water source of Hg and organic matter. Fluorescence spectroscopy results showed important changes in DOM type and quality during the snowmelt season and the soil water flow paths are activated. Changes in DOM characteristics during snowmelt improve the understanding of Hg dynamics with organic matter and elucidate transport pathways from the soil surface, ephemeral channels and groundwater to the Provo River. This study has implications for understanding Hg sources and transport mechanisms in mountain watersheds.

Organic matter loading affects lodgepole pine seedling growth.

Science.gov (United States)

Wei, Xiaohua; Li, Qinglin; Waterhouse, M J; Armleder, H M

2012-06-01

Organic matter plays important roles in returning nutrients to the soil, maintaining forest productivity and creating habitats in forest ecosystems. Forest biomass is in increasing demand for energy production, and organic matter has been considered as a potential supply. Thus, an important management question is how much organic matter should be retained after forest harvesting to maintain forest productivity. To address this question, an experimental trial was established in 1996 to evaluate the responses of lodgepole pine seedling growth to organic matter loading treatments. Four organic matter loading treatments were randomly assigned to each of four homogeneous pine sites: removal of all organic matter on the forest floor, organic matter loading quantity similar to whole-tree-harvesting residuals left on site, organic matter loading quantity similar to stem-only-harvesting residuals, and organic matter loading quantity more similar to what would be found in disease- or insect-killed stands. Our 10-year data showed that height and diameter had 29 and 35 % increase, respectively, comparing the treatment with the most organic matter loading to the treatment with the least organic matter loading. The positive response of seedling growth to organic matter loading may be associated with nutrients and/or microclimate change caused by organic matter, and requires further study. The dynamic response of seedling growth to organic matter loading treatments highlights the importance of long-term studies. Implications of those results on organic matter management are discussed in the context of forest productivity sustainability.

Arctic deltaic lake sediments as recorders of fluvial organic matter deposition

Directory of Open Access Journals (Sweden)

Jorien E Vonk

2016-08-01

Full Text Available Arctic deltas are dynamic and vulnerable regions that play a key role in land-ocean interactions and the global carbon cycle. Delta lakes may provide valuable historical records of the quality and quantity of fluvial fluxes, parameters that are challenging to investigate in these remote regions. Here we study lakes from across the Mackenzie Delta, Arctic Canada, that receive fluvial sediments from the Mackenzie River when spring flood water levels rise above natural levees. We compare downcore lake sediments with suspended sediments collected during the spring flood, using bulk (% organic carbon, % total nitrogen, 13C, 14C and molecular organic geochemistry (lignin, leaf waxes. High-resolution age models (137Cs, 210Pb of downcore lake sediment records (n=11 along with lamina counting on high-resolution radiographs show sediment deposition frequencies ranging between annually to every 15 years. Down-core geochemical variability in a representative delta lake sediment core is consistent with historical variability in spring flood hydrology (variability in peak discharge, ice jamming, peak water levels. Comparison with earlier published Mackenzie River depth profiles shows that (i lake sediments reflect the riverine surface suspended load, and (ii hydrodynamic sorting patterns related to spring flood characteristics are reflected in the lake sediments. Bulk and molecular geochemistry of suspended particulate matter from the spring flood peak and lake sediments are relatively similar showing a mixture of modern higher-plant derived material, older terrestrial permafrost material, and old rock-derived material. This suggests that deltaic lake sedimentary records hold great promise as recorders of past (century-scale riverine fluxes and may prove instrumental in shedding light on past behaviour of arctic rivers, as well as how they respond to a changing climate.

Suspended particulate matter in dwellings - the impact of tobacco smoking

Energy Technology Data Exchange (ETDEWEB)

Revsbech, P.; Korsgaard, J.; Lundqvist, G.R.

1987-01-01

The indoor concentration of suspended particulate matter (SPM) was measured in 44 retrofitted and tight dwellings, which had electric cooking and were central heated and where the basic ventilation rate in median amounted 0.23 air changes per hour as measured with a tracer dilution method. The indoor concentration of SPM was in medium 230 ..mu..g/m/sup 3/ with a strong correlation to the tobacco consumption (r/sub s/ = 0.716), but with no correlation to the frequency of airing or the basic ventilation rate. Tobacco smoking seems to be the main indoor source of SPM in contemporary dwellings. The importance of these findings is underlined by epidemiologic studies on passive smoking and health. Air quality standards for the ambient air are based on certain risk groups such as infants, children, persons with chronic obstructive lung disorders, and indoor air standards should be based on the same concepts of health protection.

Biogeochemical characteristics of suspended particulate matter in deep chlorophyll maximum layers in the southern East China Sea

Directory of Open Access Journals (Sweden)

Q. Liu

2018-04-01

Full Text Available Continental shelves and marginal seas are key sites of particulate organic matter (POM production, remineralization and sequestration, playing an important role in the global carbon cycle. Elemental and stable isotopic compositions of organic carbon and nitrogen are thus frequently used to characterize and distinguish POM and its sources in suspended particles and surface sediments in the marginal seas. Here we investigated suspended particulate matter (SPM collected around deep chlorophyll maximum (DCM layers in the southern East China Sea for particulate organic carbon and nitrogen (POC and PN contents and their isotopic compositions (δ13CPOC and δ15NPN to understand provenance and dynamics of POM. Hydrographic parameters (temperature, salinity and turbidity indicated that the study area was weakly influenced by freshwater derived from the Yangtze River during summer 2013. Elemental and isotopic results showed a large variation in δ13CPOC (−25.8 to −18.2 ‰ and δ15NPN (3.8 to 8.0 ‰, but a narrow molar C ∕ N ratio (4.1–6.3 and low POC ∕ Chl a ratio ( <  200 g g−1 in POM, and indicated that the POM in DCM layers was newly produced by phytoplankton. In addition to temperature effects, the range and distribution of δ13CPOC were controlled by variations in primary productivity and phytoplankton species composition; the former explained  ∼  70 % of the variability in δ13CPOC. However, the variation in δ15NPN was controlled by the nutrient status and δ15NNO3− in seawater, as indicated by similar spatial distribution between δ15NPN and the current pattern and water masses in the East China Sea; although interpretations of δ15NPN data should be verified with the nutrient data in future studies. Furthermore, the POM investigated was weakly influenced by the terrestrial OM supplied by the Yangtze River during summer 2013 due to the reduced sediment supply by the Yangtze River and north

Consumption-based Total Suspended Particulate Matter Emissions in Jing-Jin-Ji Area of China

Science.gov (United States)

Yang, S.; Chen, S.; Chen, B.

2014-12-01

The highly-industrialized regions in China have been facing a serious problem of haze mainly consisted of total suspended particulate matter (TSPM), which has attracted great attention from the public since it directly impairs human health and clinically increases the risks of various respiratory and pulmonary diseases. In this paper, we set up a multi-regional input-output (MRIO) model to analyze the transferring routes of TSPM emissions between regions through trades. TSPM emission from particulate source regions and sectors are identified by analyzing the embodied TSPM flows through monetary flow and carbon footprint. The track of TSPM from origin to end via consumption activities are also revealed by tracing the product supply chain associated with the TSPM emissions. Beijing-Tianjin-Hebei (Jing-Jin-Ji) as the most industrialized area of China is selected for a case study. The result shows that over 70% of TSPM emissions associated with goods consumed in Beijing and Tianjin occurred outside of their own administrative boundaries, implying that Beijing and Tianjin are net embodied TSPM importers. Meanwhile, 63% of the total TSPM emissions in Hebei Province are resulted from the outside demand, indicating Hebei is a net exporter. In addition, nearly half of TSPM emissions are the by-products related to electricity and heating supply and non-metal mineral products in Jing-Jin-Ji Area. Based on the model results, we provided new insights into establishing systemic strategies and identifying mitigation priorities to stem TSPM emissions in China. Keywords: total suspended particulate matter (TSPM); urban ecosystem modeling; multi-regional input-output (MRIO); China

Correlation between Soil Organic Matter, Total Organic Matter and ...

African Journals Online (AJOL)

A total of four sites distributed in different soils of Kelantan State, Malaysia was identified for the study. Soils were collected by depth interval of 0-10cm, 10-20cm and 20-30cm. The correlation of soil organic matter (SOM) content, total organic carbon (TOC) content, water content and soils texture for industrial area at ...

Evaluation of total suspended particulate matter in some urban and industrial cities of Pakistan

International Nuclear Information System (INIS)

Qadir, M.A.; Iqbal, M.Z.

1996-01-01

Environmental studies are very important as the living beings depend greatly on the conditions of the environment. Air is an important component of the environment, which greatly affects the health of humans, animals and plants. Environmental problems in Pakistan are growing with the rise in total sectorial growth in population, economy and industrialization. In connection with atmospheric pollution, measurement of the total suspended particulate matter (TSP) in the urban atmosphere of Lahore, Faisalabad, Rawalpindi, Islamabad, Wah Cantt. and Khanispur (background area) has been carried out and compared to that of U.S. Environmental Protection Agency Standards. (author)

Agriculture Organic Matter and Chicken Manure

Directory of Open Access Journals (Sweden)

Süleyman Taban

2013-11-01

Full Text Available Undo ubtedly organic matter content of soils is one of theim portant factor for high quality and abundant crop production. In addition to improve the physical properties ofsoil, organic matter contributest ocrop production viabeing energy source formicro-organisms in soiland contained plantnutrients. Fiftypercent of theagri cultures oil contains 1-2 % organicmatter in Turkey.In addition to being a sourceof organic matter, organic poultry manurefertilizer isricherthan other organic fertilizerse specially nitrogen content. It is possible to eliminate poultry manure based salt stress and disease factors with composting process in proper conditions.

Investigating organic matter in Fanno Creek, Oregon, Part 2 of 3: sources, sinks, and transport of organic matter with fine sediment

Science.gov (United States)

Keith, Mackenzie K.; Sobieszczyk, Steven; Goldman, Jami H.; Rounds, Stewart A.

2014-01-01

Organic matter (OM) is abundant in Fanno Creek, Oregon, USA, and has been tied to a variety of water-quality concerns, including periods of low dissolved oxygen downstream in the Tualatin River, Oregon. The key sources of OM in Fanno Creek and other Tualatin River tributaries have not been fully identified, although isotopic analyses from previous studies indicated a predominantly terrestrial source. This study investigates the role of fine sediment erosion and deposition (mechanisms and spatial patterns) in relation to OM transport. Geomorphic mapping within the Fanno Creek floodplain shows that a large portion (approximately 70%) of the banks are eroding or subject to erosion, likely as a result of the imbalance caused by anthropogenic alteration. Field measurements of long- and short-term bank erosion average 4.2 cm/year and average measurements of deposition for the watershed are 4.8 cm/year. The balance between average annual erosion and deposition indicates an export of 3,250 metric tons (tonnes, t) of fine sediment to the Tualatin River—about twice the average annual export of 1,880 t of sediment at a location 2.4 km from the creek’s mouth calculated from suspended sediment load regressions from continuous turbidity data and suspended sediment samples. Carbon content from field samples of bank material, combined with fine sediment export rates, indicates that about 29–67 t of carbon, or about 49–116 t of OM, from bank sediment may be exported to the Tualatin River from Fanno Creek annually, an estimate that is a lower bound because it does not account for the mass wasting of organic-rich O and A soil horizons that enter the stream.

Decomposition of litter and soil organic matter - Can we distinguish a mechanism for soil organic matter buildup ?

International Nuclear Information System (INIS)

Berg, B.; Johansson, M.B.; McClaugherty, C.; Virzo de Santo, A.; Ekbohm, G.

1995-01-01

This synthesis paper presents a model for estimating the buildup of soil organic matter in various types of coniferous forests. The knowledge used was obtained from a well-studied forest with good litterfall data, decomposition information and validation measurements of the soil organic matter layer. By constructing a simple model for litterfall, and the information on maximum decomposition levels for litter, we could estimate the annual increase in soil organic matter and extend this to encompass stand age. The validation measurement and the estimated amount of soil organic matter differed by about 8 or 26% over a 120-yr period, depending on the litterfall model. The estimated increased storage of soil organic matter as a consequence of climate change was found to be drastic. We thus found that the soil organic matter layer would grow about four times as fast as a result of the needle component only. This estimate was based on a comparison between latitudes with a difference of 17 degrees. 35 refs, 7 figs, 3 tabs

Soil aggregate stability and rainfall-induced sediment transport on field plots as affected by amendment with organic matter inputs

Science.gov (United States)

Shi, Pu; Arter, Christian; Liu, Xingyu; Keller, Martin; Schulin, Rainer

2017-04-01

Aggregate stability is an important factor in soil resistance against erosion, and, by influencing the extent of sediment transport associated with surface runoff, it is thus also one of the key factors which determine on- and off-site effects of water erosion. As it strongly depends on soil organic matter, many studies have explored how aggregate stability can be improved by organic matter inputs into the soil. However, the focus of these studies has been on the relationship between aggregate stability and soil organic matter dynamics. How the effects of organic matter inputs on aggregate stability translate into soil erodibility under rainfall impacts has received much less attention. In this study, we performed field plot experiments to examine how organic matter inputs affect aggregate breakdown and surface sediment transport under field conditions in artificial rainfall events. Three pairs of plots were prepared by adding a mixture of grass and wheat straw to one of plots in each pair but not to the other, while all plots were treated in the same way otherwise. The rainfall events were applied some weeks later so that the applied organic residues had sufficient time for decomposition and incorporation into the soil. Surface runoff rate and sediment concentration showed substantial differences between the treatments with and without organic matter inputs. The plots with organic inputs had coarser and more stable aggregates and a rougher surface than the control plots without organic inputs, resulting in a higher infiltration rate and lower transport capacity of the surface runoff. Consequently, sediments exported from the amended plots were less concentrated but more enriched in suspended particles (selective sediment transport. In contrast to the amended plots, there was an increase in the coarse particle fraction (> 250 µm) in the runoff from the plots with no organic matter inputs towards the end of the rainfall events due to emerging bed-load transport

Organics and Suspended Solids Removal from Hospital

Directory of Open Access Journals (Sweden)

Fakhri Y. Hmood

2013-05-01

Full Text Available The Sequencing Batch Reactor (SBR method is used for treating samples of waste water taken from hospitals in Mosul. Many run periods are used (6-24 hours for             6 months. It is found that the organics and suspended solids removal increase with increasing the period of run, it is in the range ( 96-82 % and ( 100-95 % respectively, while the pH values are nearly neutral (7.05 to 7.5.     BOD5 and SS concentrations of the effluent are within the limits of Iraqi standards,  40:30 mg/l respectively. Hence, SBR method could be used for treating hospitals, small factories and some  residential sectors waste waters.  

The destruction of organic matter

CERN Document Server

Gorsuch, T T

1970-01-01

International Series of Monographs in Analytical Chemistry, Volume 39: The Destruction of Organic Matter focuses on the identification of trace elements in organic compounds. The monograph first offers information on the processes involved in the determination of trace elements in organic matters, as well as the methods not involving complete destruction of these elements. The text surveys the sources of errors in the processes responsible in pinpointing elements in organic compounds. These processes include sampling, disruption of the samples, manipulation, and measurements. The book

Heavy metal partitioning of suspended particulate matter-water and sediment-water in the Yangtze Estuary.

Science.gov (United States)

Feng, Chenghong; Guo, Xiaoyu; Yin, Su; Tian, Chenhao; Li, Yangyang; Shen, Zhenyao

2017-10-01

The partitioning of ten heavy metals (As, Cd, Co, Cr, Cu, Hg, Ni, Pb, Sb, and Zn) between the water, suspended particulate matter (SPM), and sediments in seven channel sections during three hydrologic seasons in the Yangtze Estuary was comprehensively investigated. Special attention was paid to the role of tides, influential factors (concentrations of SPM and dissolved organic carbon, and particle size), and heavy metal speciation. The SPM-water and sediment-water partition coefficients (K p ) of the heavy metals exhibited similar changes along the channel sections, though the former were larger throughout the estuary. Because of the higher salinity, the K p values of most of the metals were higher in the north branch than in the south branch. The K p values of Cd, Co, and As generally decreased from the wet season to the dry season. Both the diagonal line method and paired samples t-test showed that no specific phase transfer of heavy metals existed during the flood and ebb tides, but the sediment-water K p was more concentrated for the diagonal line method, owing to the relatively smaller tidal influences on the sediment. The partition coefficients (especially the K p for SPM-water) had negative correlations with the dissolved organic carbon (DOC) but positive correlations were noted with the particle size for most of the heavy metals in sediment. Two types of significant correlations were observed between K p and metal speciation (i.e., exchangeable, carbonate, reducible, organic, and residual fractions), which can be used to identify the dominant phase-partition mechanisms (e.g., adsorption or desorption) of heavy metals. Copyright © 2017 Elsevier Ltd. All rights reserved.

Land-use impacts on fatty acid profiles of suspended particulate organic matter along a larger tropical river

DEFF Research Database (Denmark)

Boëchat, Iola; Krüger, Angela; Chavez, R.C.

2014-01-01

(SPOM-FAs) as indicators of land-use change in tropical catchments, and at identifying major human impacts on the biochemical composition of SPOM, which represents an important basal energy and organic matter resource for aquatic consumers. River water SPOM and total FA concentrations ranged between 2......Land-use change, such as agricultural expansion and urbanization, can affect riverine biological diversity and ecosystem functioning. Identifying the major stressors associated with catchment land-use change is a prerequisite for devising successful river conservation and restoration strategies...

210Pb and 210Po in sediments and suspended matter in the Tagus estuary, Portugal: Local enhancement of natural levels by wastes from phosphate ore processing industry

International Nuclear Information System (INIS)

Carvalho, Fernando P.

1994-01-01

Results of analyses of uranium series radionuclides in phosphate ore and in wastes released by the phosphate fertilizer industry confirm their potential for the enhancement of environmental radioactivity levels. Therefore, concentrations of 210 Pb and 210 Po were measured in bottom sediments and suspended matter in the Tagus estuary, Portugal, to assess the enhancement of radioactivity due to wastes from the phosphate industry. The concentration of 210 Pb in surface sediments in the estuary increased inversely with sediment grain-size; conversely, increased percentage of sand has a dilution effect on the concentration of 210 Pb measured in bulk sediment samples. By normalizing the data to the 210 Pb in sediments was found to be 68 ± 19 Bq kg -1 (dry wt.) in background sediments. Higher 210 Pb levels, up to 1580 Bq kg -1 (dry wt.), were measured in some bulk sediment samples. It was verified that this radionuclide has been introduced by the discharge of wastes from a phosphate fertilizer plant but enhanced concentrations are localized near the point of discharge. In other zones of the estuary, the concentrations of 210 Pb in sediments and suspended matter were generally below those measured in the zone of phosphatic releases at the Barreiro Peninsula. Concentrations higher than the predicted average concentration of unsupported 210 Pb from natural sources (atmospheric deposition, river input) were also measured in the upper estuary, both in bottom sediments and in suspended matter. It is suggested that these relatively elevated concentrations are due to the highly efficient scavenging of soluble naturally-occurring unsupported 210 Pb onto suspended matter and to co-precipitation with iron-manganese hydroxides in the fresh water-salt water mixing zone

Comparison of remote sensing algorithms for retrieval of suspended particulate matter concentration from reflectance in coastal waters

Science.gov (United States)

Freeman, Lauren A.; Ackleson, Steven G.; Rhea, William Joseph

2017-10-01

Suspended particulate matter (SPM) is a key environmental indicator for rivers, estuaries, and coastal waters, which can be calculated from remote sensing reflectance obtained by an airborne or satellite imager. Here, algorithms from prior studies are applied to a dataset of in-situ at surface hyperspectral remote sensing reflectance, collected in three geographic regions representing different water types. These data show the optically inherent exponential nature of the relationship between reflectance and sediment concentration. However, linear models are also shown to provide a reasonable estimate of sediment concentration when utilized with care in similar conditions to those under which the algorithms were developed, particularly at lower SPM values (0 to 20 mg/L). Fifteen published SPM algorithms are tested, returning strong correlations of R2>0.7, and in most cases, R2>0.8. Very low SPM values show weaker correlation with algorithm calculated SPM that is not wavelength dependent. None of the tested algorithms performs well for high SPM values (>30 mg/L), with most algorithms underestimating SPM. A shift toward a smaller number of simple exponential or linear models relating satellite remote sensing reflectance to suspended sediment concentration with regional consideration will greatly aid larger spatiotemporal studies of suspended sediment trends.

How much suspended particulate matter enters long-term in-channel storage?

Science.gov (United States)

Dietrich, Stephan; Kleisinger, Carmen; Kehl, Nora; Schubert, Birgit; Hillebrand, Gudrun

2017-04-01

The route of suspended particulate matter (SPM) downstream rivers strongly depends on discharge conditions and involves transport times and periods with resting times in deposits e.g. at areas with low-flow conditions near the channel bed. It is, however, difficult to estimate the contribution of SPM on the bed load. In this study, particle-bound polychlorinated biphenyls (PCB), which were released by an incident in the Elbe river (Central Europe) in spring 2015, could be used as unique tracer for transport pathways of SPM along the whole river stretch (over 700 km length), including low mountain ranges, lowlands, and the estuary. In 2015 the Elbe River was characterized by low-discharge conditions. Thus, the export of SPM on flood plains was strongly limited. The incident was monitored by concentration measurements of seven indicator PCB congeners along the inland part of the Elbe River as well as in the Elbe estuary. Data from ten monitoring stations (settling tanks) are considered. The total PCB load is calculated for all stations on the basis of monthly contaminant concentrations and daily suspended sediment concentrations. Monte-Carlo simulations assess the uncertainties of the calculated load. It is shown that the ratio of high versus low chlorinated PCB congeners is a suitable tracer to distinguish the PCB load of the incident from the long-term background signal (hereafter PCB6 ratio). We demonstrate that both the load of PCB as well as its chemical fingerprint allows the estimation of transport durations for the transport processes involved. Only a little part of the suspension has been transported via wash load. The PCB6 ratio is used to estimate mean transport velocities of the wash load fraction. A direct transport of wash load via the mean flow velocity of the water was not observed. Shortly after the incident, the PCB6 ratio was monitored 257 km downstream of the incident site in April 2015, in May first occurrence was monitored 514 km downstream of

Organic matter in central California radiation fogs.

Science.gov (United States)

Herckes, Pierre; Lee, Taehyoung; Trenary, Laurie; Kang, Gongunn; Chang, Hui; Collett, Jeffrey L

2002-11-15

Organic matter was studied in radiation fogs in the San Joaquin Valley of California during the California Regional Particulate Air Quality Study (CRPAQS). Total organic carbon (TOC) concentrations ranged from 2 to 40 ppm of C. While most organic carbon was found in solution as dissolved organic carbon (DOC), 23% on average was not dissolved inside the fog drops. We observe a clear variation of organic matter concentration with droplet size. TOC concentrations in small fog drops (fogwater, consistent with the enrichment of the organic matter in smaller fog drops with lower terminal settling velocities.

Polarization-based enhancement of ocean color signal for estimating suspended particulate matter: radiative transfer simulations and laboratory measurements.

Science.gov (United States)

Liu, Jia; He, Xianqiang; Liu, Jiahang; Bai, Yan; Wang, Difeng; Chen, Tieqiao; Wang, Yihao; Zhu, Feng

2017-04-17

Absorption and scattering by molecules, aerosols and hydrosols, and the reflection and transmission over the sea surface can modify the original polarization state of sunlight. However, water-leaving radiance polarization, containing embedded water constituent information, has largely been neglected. Here, the efficiency of the parallel polarization radiance (PPR) for enhancing ocean color signal of suspended particulate matter is examined via vector radiative transfer simulations and laboratory experiments. The simulation results demonstrate that the PPR has a slightly higher ocean color signal at the top-of-atmosphere as compared with that of the total radiance. Moreover, both the simulations and laboratory measurements reveal that, compared with total radiance, PPR can effectively enhance the normalized ocean color signal for a large range of observation geometries, wavelengths, and suspended particle concentrations. Thus, PPR has great potential for improving the ocean color signal detection from satellite.

Investigating Photosensitized Properties of Natural Organic Matter and Effluent Organic Matter

KAUST Repository

Niu, Xi-Zhi

2013-05-01

The photosensitized processes significantly enhance photolysis of various chemicals in the aqueous system with dissolved organic matter (DOM) as sensitizer. The excitation of chromophores on the DOM molecule further generates reactive species as triplet states DOM, singlet oxygen, hydroxyl radical, carbonate radical etc. We investigated the photosensitization properties of Beaufort Fulvic Acid, Suwannee River Fulvic Acid, South Platte River Fulvic Acid, and Jeddah wastewater treatment plant effluent organic matter with a sunlight simulator. DOM photochemical properties were characterized by observing their performances in 3DOM*, singlet oxygen, hydroxyl radical production with indirect probing protocols. Sensitized degradation of 0.1 μM and 0.02 μM 2, 4, 6- Trimethylphenol exhibited higher pseudo-first-order rate constant than that of 10 μM. Pre-irradiated DOMs were found to be depressed in photochemical properties. Photolysis of 5 different contaminants: ibuprofen, bisphenol A, acetaminophen, cimetidine, and caffeine were found to be enhanced in the presence of sensitizers. The possible reaction pathways were revealed. Long time irradiance induced change in contaminants degradation kinetics in some DOM solutions, which was proposed to be due to the irradiation initiated indirect transformation of DOMs. Key Words: Photolysis Dissolved Organic Matter, Triplet State DOM, Singlet Oxygen, Hydroxyl Radical, Contaminants Degradation.

Construction of Multi-Year Time-Series Profiles of Suspended Particulate Inorganic Matter Concentrations Using Machine Learning Approach

Directory of Open Access Journals (Sweden)

Pannimpullath R. Renosh

2017-12-01

Full Text Available Hydro-sedimentary numerical models have been widely employed to derive suspended particulate matter (SPM concentrations in coastal and estuarine waters. These hydro-sedimentary models are computationally and technically expensive in nature. Here we have used a computationally less-expensive, well-established methodology of self-organizing maps (SOMs along with a hidden Markov model (HMM to derive profiles of suspended particulate inorganic matter (SPIM. The concept of the proposed work is to benefit from all available data sets through the use of fusion methods and machine learning approaches that are able to process a growing amount of available data. This approach is applied to two different data sets entitled “Hidden” and “Observable”. The hidden data are composed of 15 months (27 September 2007 to 30 December 2008 of hourly SPIM profiles extracted from the Regional Ocean Modeling System (ROMS. The observable data include forcing parameter variables such as significant wave heights ( H s and H s 50 (50 days from the Wavewatch 3-HOMERE database and barotropic currents ( U b a r and V b a r from the Iberian–Biscay–Irish (IBI reanalysis data. These observable data integrate hourly surface samples from 1 February 2002 to 31 December 2012. The time-series profiles of the SPIM have been derived from four different stations in the English Channel by considering 15 months of output hidden data from the ROMS as a statistical representation of the ocean for ≈11 years. The derived SPIM profiles clearly show seasonal and tidal fluctuations in accordance with the parent numerical model output. The surface SPIM concentrations of the derived model have been validated with satellite remote sensing data. The time series of the modeled SPIM and satellite-derived SPIM show similar seasonal fluctuations. The ranges of concentrations for the four stations are also in good agreement with the corresponding satellite data. The high accuracy of the

Influence of particulate matter on microfouling biomass in the Arabian Sea

Digital Repository Service at National Institute of Oceanography (India)

Bhosle, N.B.; Nandakumar, K.; Wagh, A.B.

~ E :; :; 00 " " 200 '\\00 6001&. I&. Olslonc. from rne St>cre tn. miles! Leg , 0----4L~2 L~3 Leo .; Log $ Fig.3 Suspended matter (A), and particulate organic carbon (B) of surface seawater. and microfouling biomass as dry weight (C) and organic carbon...

Spatiotemporal Characterization of Chromophoric Dissolved Organic Matter (CDOM and CDOM-DOC Relationships for Highly Polluted Rivers

Directory of Open Access Journals (Sweden)

Sijia Li

2016-09-01

Full Text Available Spectral characteristics of CDOM (Chromophoric dissolved organic matter in water columns are a key parameter for bio-optical modeling. Knowledge of CDOM optical properties and spatial discrepancy based on the relationship between water quality and spectral parameters in the Yinma River watershed with in situ data collected from highly polluted waters are exhibited in this study. Based on the comprehensive index method, the riverine waters showed serious contamination; especially the chemical oxygen demand (COD, iron (Fe, manganese (Mn, mercury (Hg and dissolved oxygen (DO were out of range of the contamination warning. Dissolved organic carbon (DOC and total suspended matter (TSM with prominent non-homogenizing were significantly high in the riverine waters, but chlorophyll-a (Chl-a was the opposite. The ternary phase diagram showed that non-algal particle absorption played an important role in total non-water light absorption (>50% in most sampling locations, and mean contributions of CDOM were 13% and 22% in the summer and autumn, respectively. The analysis of the ratio of absorption at 250–365 nm (E250:365 and the spectral slope (S275–295 indicated that CDOM had higher aromaticity and molecular weight in autumn than in summer, which is consistent with the results of water quality and the CDOM relative contribution rate. Redundancy analysis (RDA indicated that the environmental variables OSM (Organic suspended matter had a strong correlation with CDOM absorption, followed by heavy metals, e.g., Mn, Hg and Cr6+. However, for the specific UV absorbance (SUVA254, the seasonal values showed opposite results compared with the reported literature. The potential reasons were that more UDOM (uncolored dissolved organic matter from human sources (wastewater effluent existed in the waters. Terrigenous inputs simultaneously are in relation to the aCDOM(440-DOC relationship with the correlation coefficient of 0.90 in the summer (two-tailed, p < 0

The dynamics of suspended particulate matter (SPM) and chlorophyll- a from intratidal to annual time scales in a coastal turbidity maximum

NARCIS (Netherlands)

van der Hout, C.M.; Witbaard, R.; Bergman, M.J.N.; Duineveld, G.C.A.; Rozemeijer, M.J.C.; Gerkema, T.

2017-01-01

The analysis of 1.8 years of data gives an understanding of the response to varying forcing of suspended particulate matter (SPM) and chlorophyll-a (CHL-a) in a coastal turbidity maximum zone (TMZ). Both temporal and vertical concentration variations in the near-bed layer (0–2 m) in the shallow (11

The dynamics of suspended particulate matter (SPM) and chlorophyll-a from intratidal to annual time scales in a coastal turbidity maximum

NARCIS (Netherlands)

Hout, van der C.M.; Witbaard, R.; Bergman, M.J.N.; Duineveld, G.C.A.; Rozemeijer, M.J.C.; Gerkema, T.

2017-01-01

The analysis of 1.8. years of data gives an understanding of the response to varying forcing of suspended particulate matter (SPM) and chlorophyll-a (CHL-a) in a coastal turbidity maximum zone (TMZ). Both temporal and vertical concentration variations in the near-bed layer (0-2. m) in the shallow

Characterisation of the suspended particulate matter in a stratified estuarine environment employing complementary techniques

Science.gov (United States)

Thomas, Luis P.; Marino, Beatriz M.; Szupiany, Ricardo N.; Gallo, Marcos N.

2017-09-01

The ability to predict the sediment and nutrient circulation within estuarine waters is of significant economic and ecological importance. In these complex systems, flocculation is a dynamically active process that is directly affected by the prevalent environmental conditions. Consequently, the floc properties continuously change, which greatly complicates the characterisation of the suspended particle matter (SPM). In the present study, three different techniques are combined in a stratified estuary under quiet weather conditions and with a low river discharge to search for a solution to this problem. The challenge is to obtain the concentration, size and flux of suspended elements through selected cross-sections using the method based on the simultaneous backscatter records of 1200 and 600 kHz ADCPs, isokinetic sampling data and LISST-25X measurements. The two-ADCP method is highly effective for determining the SPM size distributions in a non-intrusive way. The isokinetic sampling and the LISST-25X diffractometer offer point measurements at specific depths, which are especially useful for calibrating the ADCP backscatter intensity as a function of the SPM concentration and size, and providing complementary information on the sites where acoustic records are not available. Limitations and potentials of the techniques applied are discussed.

Terrestrially derived dissolved organic matter in the chesapeake bay and the middle atlantic bight

Science.gov (United States)

Mitra, Siddhartha; Bianchi, Thomas S.; Guo, Laodong; Santschi, Peter H.

2000-10-01

Concentrations of lignin-phenols were analyzed in high molecular weight dissolved organic matter (0.2 μm > HMW DOM > 1 kDa) isolated from surface waters of the Chesapeake Bay (C. Bay), and surface and bottom waters of the Middle Atlantic Bight (MAB). The abundance of lignin-phenols in HMW DOM was higher in the C. Bay (0.128 ± 0.06 μg L -1) compared to MAB surface waters (0.016 ± 0.004 μg L -1) and MAB bottom waters (0.005 ± 0.003 μg L -1). On an organic carbon-normalized basis, lignin-phenol abundances in the HMW DOM (i.e., Λ 6), were significantly higher ( p vanillin (Ad/Al) V in HMW DOM, indicative of lignin decay, ranged from 0.611 to 1.37 in C. Bay, 0.534 to 2.62 in MAB surface waters, and 0.435 to 1.96 in MAB bottom water. Ratios of S/V and (Ad/Al) V showed no significant differences between each environment, providing no evidence of any compositionally distinct input of terrestrial organic matter into each environment. When considering depth profiles of suspended particulate matter in the MAB, with C:N ratios, and bulk radiocarbon ages and stable carbon isotopic values in HMW DOM isolated from these areas, two scenarios present themselves regarding the sources and transport of terrestrially derived HMW DOM in the MAB. Scenario #1 assumes that a low amount of refractory terrestrial organic matter and old DOC are uniformly distributed in the oceans, both in surface and bottom waters, and that primary production in surface waters increases DOC with low lignin and younger DOC which degrades easily. In this case, many of the trends in age and biomarker composition likely reflect general patterns of Atlantic Ocean surface and bottom water circulation in the area of the MAB. Scenario 2 assumes terrestrial organic matter in bottom waters of the MAB may have originated from weathered shelf and slope sediments in nearshore areas via a combination of mechanisms (e.g., diffusion, recent resuspension events, and/or desorption of DOM from riverine POM buried deep

The behaviour of cesium 137, chromium 51, cobalt 60, Manganese 54, sodium 22 and zinc 65 in simulated estuarine environments. Effects of suspended mineral particles and dissolved organic matters

International Nuclear Information System (INIS)

Mahler, P.

1985-09-01

This laboratory investigation studied the retention of 6 radionuclides (cesium 137, chrome 51, cobalt 60, manganese 54, sodium 22 and zinc 65) on three types of clay particles (kaolinite, illite, montmorillonite) and on sediments, suspended in media with salinities ranging between 0 and 34 per mill, with or without organic matters. Measurement of the radioactivity retained by the particles after 5 days' contact with the radionuclide made it possible to calculate the percentages retained and the distribution coefficients, and to follow their evolution versus salinity. Parallel experiments studied the behaviours of the 6 radionuclides as a function of experimental factors (wall effect, contact time..). An exhaustive bibliographic review gives the state-of-the-art of the knowledge. The following conclusions were derived: - the retention of all the radionuclides but chromium 51 decreased as soon as a low salinity appeared. Chromium (available as Cr 3+ ) precipitated quickly and strongly during fixation whatever the surfaces or the conditions: - as for the role of the clay type, illite showed a strong affinity for cesium 137; manganese 54 had a particular behaviour with montmorillonite that enhanced its precipitation into MnO 2 ; with cobalt, sodium and zinc, the percentages retained were always [fr

Particulate matter from re-suspended mineral dust and emergency cause-specific respiratory hospitalizations in Hong Kong

Science.gov (United States)

Pun, Vivian C.; Tian, Linwei; Ho, Kin-fai

2017-09-01

While contribution from non-exhaust particulate matter (PM) emissions towards traffic-related emissions is increasing, few epidemiologic evidence of their health impact is available. We examined the association of short-term exposure to PM10 apportioned to re-suspended mineral dust with emergency hospitalizations for three major respiratory causes in Hong Kong between 2001 and 2008. Time-series regression model was constructed to examine association of PM10 from re-suspended mineral dust with emergency hospitalizations for upper respiratory infection (URI), chronic obstructive pulmonary disease (COPD) and asthma at exposure lag 0-5 days, adjusting for time trends, seasonality, temperature and relative humidity. An interquartile range (6.8 μg/m3) increment in re-suspended mineral dust on previous day was associated with 0.66% (95% CI: 0.12, 0.98) increase in total respiratory hospitalizations, and 1.01% (95% CI: 0.14, 1.88) increase in URI hospitalizations. A significant 0.66%-0.80% increases in risk of COPD hospitalizations were found after exposure to re-suspended mineral dust at lag 3 or later. Exposure to mineral dust at lag 4 was linked to 1.71% increase (95% CI: 0.14, 2.22) in asthma hospitalizations. Associations from single-pollutant models remained significant in multi-pollutant models, which additionally adjusted for PM10 contributing from vehicle exhaust, regional combustion, residual oil, fresh sea salt, aged sea salt, secondary nitrate and secondary sulfate, or gaseous pollutants (i.e., nitrogen dioxide, sulfur dioxide, or ozone), respectively. Our findings provide insight into the biological mechanism by which non-exhaust pollution may be associated with risk of adverse respiratory outcomes, and also stress the needs for strategies to reduce emission and re-suspension of mineral dust. More research is warranted to assess the health effects of different non-exhaust PM emissions under various roadway conditions and vehicle fleets.

239PU sorption by suspended matter from Hueznar reservoir (Southern Spain): experimental and modelling study

International Nuclear Information System (INIS)

El Mrabet, R.; Abril, J.M.; Barros, H.; Manjon, G.

2004-01-01

Kinetic transfer coefficients are important parameters to understand and reliably model the behaviour of non-conservative radionuclides in aquatic environments. This report pertains to a series of radiotracer experiments on 239 Pu uptake in natural unfiltered waters from the Hueznar reservoir (southern Spain). The experimental procedure ensures the preservation of environmental conditions and the dissolved Pu activity was measured by liquid scintillation technique. The data suggest that the main pathways for Pu uptake consist of two parallel and reversible reactions followed by a consecutive reversible reaction. We studied the effects of suspended matter concentrations and the specific surface area on the kinetic transfer coefficients. (author)

Podzolisation and soil organic matter dynamics

NARCIS (Netherlands)

Buurman, P.; Jongmans, A.G.

2005-01-01

Present models of podzolisation emphasize the mobilization and precipitation of dissolved organic matter. together with Al(-silicates) and Fe. Such models cannot explain the dominance of pellet-like organic matter in most boreal podzols and in well-drained podzols outside the boreal zone, and the

Polycyclic aromatic hydrocarbons in suspended particulate matter and sediments from the Pearl River Estuary and adjacent coastal areas, China

International Nuclear Information System (INIS)

Luo Xiaojun; Chen Shejun; Mai Bixian; Yang Qingshu; Sheng Guoying; Fu Jiamo

2006-01-01

The spatial distribution, composition, and sources of polycyclic aromatic hydrocarbons (PAHs) in sediments and suspended particulate matter (SPM) from the Pearl River Estuary and adjacent coastal areas were examined. Total PAH concentrations varied from 189 to 637 ng/g in sediments and 422 to 1850 ng/g in SPM. PAHs were dominated by 5,6-ring compounds in sediments and by 2,3-ring compounds in SPM samples. Assessment of PAH sources suggested that biomass and coal combustion is the major PAH source to the outer part of the estuary sediments and that petroleum combustion is the major PAH source to the inner part of estuary sediments. As for SPM samples, PAH isomer pair ratios indicated multiple (petroleum, petroleum combustion, and biomass and coal combustion) PAH sources, and significant temporal variations could exist for the sources of water column PAHs in the study area. The distribution of perylene in SPM samples indicated that the river was the dominant source of perylene in SPM and that perylene could be taken as an index to assess the contribution of river inflow to the total PAHs in SPM samples. The high concentration of perylene in the sediment was indicative of an in situ biogenic origin. - PAH were determined in suspended particulate matter and sediments from Pearl River Estuary

Removal of nitrogen and organic matter in a submerged-membrane bioreactor operating in a condition of simultaneous nitrification and denitrification

Directory of Open Access Journals (Sweden)

Izabela Major Barbosa

2016-04-01

Full Text Available This study evaluated the removal of nitrogen and organic matter in a membrane bioreactor system operating in a condition of simultaneous nitrification and denitrification controlled by intermittent aeration. A submerged-membrane system in a bioreactor was used in a pilot scale to treat domestic wastewater. The dissolved oxygen concentration was maintained between 0.5 and 0.8 mg L-1. The concentration of the mixed liquor suspended solids (MLSS in the system ranged from 1 to 6 g L-1. The system efficiency was evaluated by the removal efficiency of organic matter, quantified by Chemical Oxygen Demand (COD, Biochemical Oxygen Demand (BOD5 and Total Organic Carbon (TOC. Nitrogen removal was assessed by quantifying Total Kjeldahl Nitrogen (TKN and ammonia nitrogen. During the system start-up, the removal efficiencies of COD and NTK were around 90% and 80%, respectively. After the simultaneous nitrification and denitrification (SND conditions were established, the removal efficiencies of COD and NTK were 70% and 99%, respectively. These results showed that sewage treatment with the membrane bioreactor (MBR system, operating with simultaneous nitrification and denitrification conditions, was able to remove organic matter and promote nitrification and denitrification in a single reactor, producing a high-quality permeate.

When Organization Fails: Why Authority Matters

DEFF Research Database (Denmark)

Blaschke, Steffen

2015-01-01

Review of: James R. Taylor and Elizabeth J. Van Every / When Organization Fails: Why Authority Matters. (New York: Routledge, 2014. 220 pp. ISBN: 978 0415741668)......Review of: James R. Taylor and Elizabeth J. Van Every / When Organization Fails: Why Authority Matters. (New York: Routledge, 2014. 220 pp. ISBN: 978 0415741668)...

Physical Conditions Regulate the Fungal to Bacterial Ratios of a Tropical Suspended Soil

Directory of Open Access Journals (Sweden)

Julian Donald

2017-12-01

Full Text Available As a source of ‘suspended soils’, epiphytes contribute large amounts of organic matter to the canopy of tropical rain forests. Microbes associated with epiphytes are responsible for much of the nutrient cycling taking place in rain forest canopies. However, soils suspended far above the ground in living organisms differ from soil on the forest floor, and traditional predictors of soil microbial community composition and functioning (nutrient availability and the activity of soil organisms are likely to be less important. We conducted an experiment in the rain forest biome at the Eden Project in the U.K. to explore how biotic and abiotic conditions determine microbial community composition and functioning in a suspended soil. To simulate their natural epiphytic lifestyle, bird’s nest ferns (Asplenium nidus were placed on a custom-built canopy platform suspended 8 m above the ground. Ammonium nitrate and earthworm treatments were applied to ferns in a factorial design. Extracellular enzyme activity and Phospholipid Fatty Acid (PLFA profiles were determined at zero, three and six months. We observed no significant differences in either enzyme activity or PLFA profiles between any of the treatments. Instead, we observed decreases in β-glucosidase and N-acetyl-glucosaminidase activity, and an increase in phenol oxidase activity across all treatments and controls over time. An increase in the relative abundance of fungi during the experiment meant that the microbial communities in the Eden Project ferns after six months were comparable with ferns sampled from primary tropical rain forest in Borneo.

Radionuclides in water/suspended matter/sediment systems, and assessment of radiation burden

International Nuclear Information System (INIS)

1988-01-01

The 'General Instructions and Reference Values' (ABG) for calculating the radiation dose to the population from radioactive effluents discharged into the atmosphere or surface waters is the basis for assessing the dose commitment of the population with reference to the main exposure pathways. The ABG, however, contains little information on the deposition of radioactive substances with suspended matter in a river. Therefore, a number of specific studies have been carried out by various research institutes on behalf of the then competent Ministry of the Interior. The results are summarized in the book, methods and measuring programs are explained, and a full documentation of measured data and model parameters derived is given and discussed. The conclusions to be drawn from the field or laboratory analyses are set out, and are put together to build a more differentiating and hence more realistic model for assessing the radiation exposure of man due to contamination of sediments and sewage sludge. (orig./HP) With 83 figs., 52 tabs [de

Chlorophyll 'a' particulate organic carbon and suspended load from the mangrove areas of Cochin backwaters

Digital Repository Service at National Institute of Oceanography (India)

Sheeba, P.; Devi, K.S.; Balasubramanian, T.; Sankaranarayanan, V.N.

Chlorophyll 'a' Particulate Organic Carbon and suspended load were estimated for one year from two distinct mangrove areas of Cochin backwaters, viz. Puthuvypeen and Nettoor. Environmental parameters like tau degrees C, S ppt and pH were also...

Behaviour of suspended particulate matter (SPM and selected trace metals during the 2002 summer flood in the River Elbe (Germany at Magdeburg monitoring station

Directory of Open Access Journals (Sweden)

M. Baborowski

2004-01-01

Full Text Available In August 2002, in the worst flooding in more than 100 years, the River Elbe destroyed built-up areas and caused widespread erosion and the relocation of soils and river sediments. To assess the pollutants entering the water, surveys of dissolved constituents and suspended particulate matter (SPM were carried out daily during the flood at a monitoring station near Magdeburg. The sampling point is part of the network of the International Commission for the Protection of the Elbe (ICPE. The results were compared with those of previous flood studies which used the same sampling strategy. Unlike past floods, the 2002 flood was characterised by the transport of relatively fine suspended material with a low mass concentration. Owing to different input sources, the maxima of dry weight and of particle number concentration occurred at different times. Hg, Fe, Mn, Zn, Cu, Ni and Cr showed a maximum concentration concurrent with the dry weight of the SPM, whereas the maximum concentrations of As, Pb, and Cd coincided with the particle number concentration peak. The concentration of particulate matter decreased rapidly, unlike the concentrations of dissolved substances such as DOC and trace metals, as well as the values of UV extinction, all of which remained high for a longer period. Comparing the results of the 2002 flood with the winter floods in 1995, 1999 and 2000, revealed increased values of As and Pb as well as higher concentrations of dissolved compounds. Keywords: river, flood, transport, suspended particulate matter, trace metals, dissolved compounds, Elbe

Natural organic matter to enhance electrokinetic transport of PAH

Energy Technology Data Exchange (ETDEWEB)

Suer, P.; Joensson, S.; Allard, B. [Man-Technology-Environment Research Centre, Oerebro Univ. (Sweden)

2001-07-01

The remediation of contaminated soil can be enhanced with natural organic matter (NOM) as a complexing agent for pollutants. NOM has both hydrophobic and acidic properties, so that it is charged and thus subject to electroremediation. At the same time many contaminants have a high affinity for organic matter. Organic matter was produced in situ in an electric field or added in solute form. The resulting dissolved organic matter was transported towards the cathode, probably by cationic colloids. Produced dissolved organic matter included high molecular weight molecules near the cathode, at the site of pH buffering. Pyrene and phenanthrene were likewise transported towards the cathode. Movement was small but distinctive in 2-day experiments. Clay influence the soil/water distribution of the PAH but no effect on the total transport could be discerned. The presence of solid organic matter in the soil removed all PAH from the water phase, even though the concentration of organic matter in the water phase was high as well. (orig.)

Origin and distribution of the organic matter in the distal lobe of the Congo deep-sea fan - A Rock-Eval survey

Science.gov (United States)

Baudin, François; Stetten, Elsa; Schnyder, Johann; Charlier, Karine; Martinez, Philippe; Dennielou, Bernard; Droz, Laurence

2017-08-01

The Congo River, the second largest river in the world, is a major source of organic matter for the deep Atlantic Ocean because of the connection of its estuary to the deep offshore area by a submarine canyon which feeds a vast deep-sea fan. The lobe zone of this deep-sea fan is the final receptacle of the sedimentary inputs presently channelled by the canyon and covers an area of 2500 km². The quantity and the source of organic matter preserved in recent turbiditic sediments from the distal lobe of the Congo deep-sea fan were assessed using Rock-Eval pyrolysis analyses. Six sites, located at approximately 5000 m water-depth, were investigated. The mud-rich sediments of the distal lobe contain high amounts of organic matter ( 3.5 to 4% Corg), the origin of which is a mixture of terrestrial higher-plant debris, soil organic matter and deeply oxidized phytoplanktonic material. Although the respective contribution of terrestrial and marine sources of organic matter cannot be precisely quantified using Rock-Eval analyses, the terrestrial fraction is dominant according to similar hydrogen and oxygen indices of both suspended and bedload sediments from the Congo River and that deposited in the lobe complex. The Rock-Eval signature supports the 70% to 80% of the terrestrial fraction previously estimated using C/N and δ13Corg data. In the background sediment, the organic matter distribution is homogeneous at different scales, from a single turbiditic event to the entire lobe, and changes in accumulation rates only have a limited effect on the quantity and quality of the preserved organic matter. Peculiar areas with chemosynthetic bivalves and/or bacterial mats, explored using ROV Victor 6000, show a Rock-Eval signature similar to background sediment. This high organic carbon content associated to high sedimentation rates (> 2 to 20 mm.yr-1) in the Congo distal lobe complex implies a high burial rate for organic carbon. Consequently, the Congo deep-sea fan represents an

Pre-aged soil organic carbon as a major component of the Yellow River suspended load: Regional significance and global relevance

Science.gov (United States)

Tao, Shuqin; Eglinton, Timothy I.; Montluçon, Daniel B.; McIntyre, Cameron; Zhao, Meixun

2015-03-01

Large rivers connect the continents and the oceans, and corresponding material fluxes have a global impact on marine biogeochemistry. The Yellow River transports vast quantities of suspended sediments to the ocean, yet the nature of the particulate organic carbon (POC) carried by this system is not well known. The focus of this study is to characterize the sources, composition and age of suspended POC collected near the terminus of this river system, focusing on the abundance and carbon isotopic composition (13C and 14C) of specific biomarkers. The concentrations of vascular plant wax lipids (long-chain (≥C24) n-alkanes, n-fatty acids) and POC co-varied with total suspended solid (TSS) concentrations, indicating that both were controlled by the overall terrestrial sediment flux. POC exhibited relatively uniform δ13C values (-23.8 to -24.2‰), and old radiocarbon ages (4000-4640 yr). However, different biomarkers exhibited a wide range of 14C ages. Short-chain (C16, C18) fatty acid 14C ages were variable but generally the youngest organic components (from 502 yr to modern), suggesting they reflect recently biosynthesized material. Lignin phenol 14C ages were also variable and relatively young (1070 yr to modern), suggesting rapid export of carbon from terrestrial primary production. In contrast, long-chain plant wax lipids display relatively uniform and significantly older 14C ages (1500-1800 yr), likely reflecting inputs of pre-aged, mineral-associated soil OC from the Yellow River drainage basin. Even-carbon-numbered n-alkanes yielded the oldest 14C ages (up to 26 000 yr), revealing the presence of fossil (petrogenic) OC. Two isotopic mass balance approaches were explored to quantitively apportion different OC sources in Yellow River suspended sediments. Results indicate that the dominant component of POC (53-57%) is substantially pre-aged (1510-1770 yr), and likely sourced from the extensive loess-paleosol deposits outcropping within the drainage basin. Of

The effects of organic matter-mineral interactions and organic matter chemistry on diuron sorption across a diverse range of soils.

Science.gov (United States)

Smernik, Ronald J; Kookana, Rai S

2015-01-01

Sorption of non-ionic organic compounds to soil is usually expressed as the carbon-normalized partition coefficient (KOC), because it is assumed that the main factor that influences the amount sorbed is the organic carbon content of the soil. However, KOC can vary by a factor of at least ten across a range of soils. We investigated two potential causes of variation in diuron KOC - organic matter-mineral interactions and organic matter chemistry - for a diverse set of 34 soils from Sri Lanka, representing a wide range of soil types. Treatment with hydrofluoric acid (HF-treatment) was used to concentrate soil organic matter. HF-treatment increased KOC for the majority of soils (average factor 2.4). We attribute this increase to the blocking of organic matter sorption sites in the whole soils by minerals. There was no significant correlation between KOC for the whole soils and KOC for the HF-treated soils, indicating that the importance of organic matter-mineral interactions varied greatly amongst these soils. There was as much variation in KOC across the HF-treated soils as there was across the whole soils, indicating that the nature of soil organic matter is also an important contributor to KOC variability. Organic matter chemistry, determined by solid-state (13)C nuclear magnetic resonance (NMR) spectroscopy, was correlated with KOC for the HF-treated soils. In particular, KOC increased with the aromatic C content (R=0.64, p=1×10(-6)), and decreased with O-alkyl C (R=-0.32, p=0.03) and alkyl C (R=-0.41, p=0.004) content. Copyright © 2014 Elsevier Ltd. All rights reserved.

Characterization and morphology of solids suspended in rain water

International Nuclear Information System (INIS)

Iturbe G, J.L.; Lopez M, B.E.; Torre O, J. De la

2000-01-01

This work presents the results obtained from the analysis of rain water in Mexico. The study treats over the characterization and morphology of the solids suspended in form of particles in the atmosphere. The solids suspended were obtained of the pluvial precipitations after these have been centrifuged. Subsequently of the separation, the particulate matter was analysed by Sem and X-ray dispersive energy

Molybdenum isotope fractionation during adsorption to organic matter

Science.gov (United States)

King, Elizabeth K.; Perakis, Steven; Pett-Ridge, Julie C.

2018-01-01

Organic matter is of emerging interest as a control on molybdenum (Mo) biogeochemistry, and information on isotope fractionation during adsorption to organic matter can improve interpretations of Mo isotope variations in natural settings. Molybdenum isotope fractionation was investigated during adsorption onto insolubilized humic acid (IHA), a surrogate for organic matter, as a function of time (2–170 h) and pH (2–7). For the time series experiment performed at pH 4.2, the average Mo isotope fractionation between the solution and the IHA (Δ98Mosolution-IHA) was 1.39‰ (± 0.16‰, 2σ, based on 98Mo/95Mo relative to the NIST 3134 standard) at steady state. For the pH series experiment, Mo adsorption decreased as pH increased from 2.0 to 6.9, and the Δ98Mosolution-IHA increased from 0.82‰ to 1.79‰. We also evaluated natural Mo isotope patterns in precipitation, foliage, organic horizon, surface mineral soil, and bedrock from 12 forested sites in the Oregon Coast Range. The average Mo isotope offset observed between precipitation and organic (O) horizon soil was 2.1‰, with light Mo isotopes adsorbing preferentially to organic matter. Fractionation during adsorption to organic matter is similar in magnitude and direction to prior observations of Mo fractionation during adsorption to Fe- and Mn- (oxyhydr)oxides. Our finding that organic matter influences Mo isotope composition has important implications for the role of organic matter as a driver of trace metal retention and isotopic fractionation.

Removal of Cs+, Sr2+, and Co2+ ions from the mixture of organics and suspended solids aqueous solutions by zeolites

International Nuclear Information System (INIS)

Fang, Xiang Hong; Fang, Fang; Lu, Chun Hai; Zheng, Lei

2017-01-01

Serving as an excellent adsorbent and inorganic ion exchanger in the water purification field, zeolite 4A has in this work presented a strong capability for purifying radioactive waste, such as Sr 2+ , Cs + , and Co 2+ in water. During the processes of decontamination and decommissioning of suspended solids and organics in low-level radioactive wastewater, the purification performance of zeolite 4A has been studied. Under ambient temperature and neutral condition, zeolite 4A absorbed simulated radionuclides such as Sr 2+ , Cs + , and Co 2+ with an absorption rate of almost 90%. Additionally, in alkaline condition, the adsorption percentage even approached 98.7%. After conducting research on suspended solids and organics of zeolite 4A for the treatment of radionuclides, it was found that the suspended clay was conducive to absorption, whereas the absorption of organics in solution was determined by the species of radionuclides and organics. Therefore, zeolite 4A has considerable potential in the treatment of radioactive wastewater

Applicability of X-ray fluorescence analysis for heavy metal monitoring in sediments and suspended matter of surface bodies of water

International Nuclear Information System (INIS)

Kallenberg, U.

1993-01-01

Among the modern physical-chemical methods of analysis, X-ray fluorescence analysis is one of the most important owing to its wide spectrum of applications, especially as a precise and reliable method for monitoring heavy metals in air, water, and soil. The authors investigated whether it is also suitable for routine monitoring of heavy metals in sediments and suspended matter in accordance with the specifications of the Sewage Sludge Ordinance. (orig.) [de

Deuterium in organic matter

International Nuclear Information System (INIS)

Straaten, C.M. van der.

1981-01-01

In order to obtain an insight in the processes governing the macroclimate on earth, a knowledge is required of the behaviour of climates in the past. It is well known that D/H ratio of rain varies with temperature determined by latitude as well as by season. Because land plants use this water during the assimilation process, it is expected that the D/H variations are propagated in the organic plant matter. The D/H palaeoclimatic method has therefore been applied to peat to distinguish between the chemical constituents and trace the stable hydrogen fraction in the organic matter. The relation between the hydrogen isotopic composition of precipitation and climatic factors such as the temperature have also been studied. (Auth.)

Organic matter dynamics and N mineralization in grassland soils

OpenAIRE

Hassink, J.

1995-01-01

The aims of this study are i) to improve our understanding of the interactions between soil texturelsoil structure, soil organic matter, soil biota and mineralization in grassland soils, ii) to develop a procedure that yields soil organic matter fractions that can be determined directly and can be used in soil organic matter models, iii) to develop a model that predicts the long-term dynamics of soil organic matter, iv) to develop a simple model that can be used by farmers and advi...

Separating the effects of organic matter-mineral interactions and organic matter chemistry on the sorption of diuron and phenanthrene.

Science.gov (United States)

Ahangar, Ahmad Gholamalizadeh; Smernik, Ronald J; Kookana, Rai S; Chittleborough, David J

2008-06-01

Even though it is well established that soil C content is the primary determinant of the sorption affinity of soils for non-ionic compounds, it is also clear that organic carbon-normalized sorption coefficients (K(OC)) vary considerably between soils. Two factors that may contribute to K(OC) variability are variations in organic matter chemistry between soils and interactions between organic matter and soil minerals. Here, we quantify these effects for two non-ionic sorbates-diuron and phenanthrene. The effect of organic matter-mineral interactions were evaluated by comparing K(OC) for demineralized (HF-treated) soils, with K(OC) for the corresponding whole soils. For diuron and phenanthrene, average ratios of K(OC) of the HF-treated soils to K(OC) of the whole soils were 2.5 and 2.3, respectively, indicating a substantial depression of K(OC) due to the presence of minerals in the whole soils. The effect of organic matter chemistry was determined by correlating K(OC) against distributions of C types determined using solid-state (13)C NMR spectroscopy. For diuron, K(OC) was positively correlated with aryl C and negatively correlated with O-alkyl C, for both whole and HF-treated soils, whereas for phenanthrene, these correlations were only present for the HF-treated soils. We suggest that the lack of a clear effect of organic matter chemistry on whole soil K(OC) for phenanthrene is due to an over-riding influence of organic matter-mineral interactions in this case. This hypothesis is supported by a correlation between the increase in K(OC) on HF-treatment and the soil clay content for phenanthrene, but not for diuron.

Cycling downwards - dissolved organic matter in soils

NARCIS (Netherlands)

Kaiser, K.; Kalbitz, K.

2012-01-01

Dissolved organic matter has been recognized as mobile, thus crucial to translocation of metals, pollutants but also of nutrients in soil. We present a conceptual model of the vertical movement of dissolved organic matter with soil water, which deviates from the view of a chromatographic stripping

Particles matter: Transformation of suspended particles in constructed wetlands

NARCIS (Netherlands)

Mulling, B.T.M.

2013-01-01

This thesis shows that constructed wetlands transform suspended particles in (treated) municipal wastewater through selective precipitation in ponds, biological filtering by plankton communities and physical and biological retention in reed beds. These processes effectively remove faecal indicator

The Effect of Hurricane Lili on the Distribution of Organic Matter in the Inner Louisiana Shelf (Gulf of Mexico, USA)

Science.gov (United States)

Clinton, R.; Goni, M. A.; Gisewhite, R.; Monacci, N.; Gordon, E.; Allison, M.; Kineke, G.

2004-12-01

Suspended particles and surface sediments were collected from the inner shelf of the Louisiana central coast following the passage of Hurricane Lili. The elemental and stable isotopic data of these samples were compared to those determined prior to the hurricane. A week after the storm passage, turbidity levels and total suspended sediment concentrations were not that different from pre-storm values, suggesting most of the suspended sediments must have settled soon after the storm passage. Particulate organic carbon (POC) concentrations ranged from 0.1 mg/L to over 2.0 mg/L, with the highest concentrations measured near the seabed and in the inshore portions of the study area. In these locations, suspended particles displayed high POC/Chlorophyll ratios (POC/Chl of 400 to 4,000) and relatively elevated POC/particulate nitrogen ratios (POC/PN of 10 to 14) that indicated their source was locally resuspended seabed sediments. Relatively low POC/Chl (~200) and POC:PN (~7) ratios consistent with significant contributions from phytoplankton were measured only in the surface waters of the most offshore locations. Post hurricane sediment deposition resulted in a storm layer that ranged from 0.5 to 19 cm in thickness. The storm layer was generally composed of silty clays with a coarser, somewhat sandy 1-2 cm basal layer. These storm deposits were characterized by relatively high SA and OC contents. Similarities in the characteristics of the organic matter before and after reinforce the hypothesis that the source of the storm deposits was the finer fraction of locally resuspended seabed sediments, with little evidence for allochthonous land-derived inputs.

Clay-associated organic matter in kaolinitic and smectitic soils

NARCIS (Netherlands)

Wattel-Koekkoek, E.J.W.

2002-01-01

The primary source of soil organic matter is plant debris of all kinds, such as dead roots, leaves and branches that enter into the soil and are then biologically decomposed at variable rates. Organic matter has many different important functions on a local and global scale. Soil organic matter is

Heavy metal toxicity and bioavailability of dissolved nutrients to a bacterivorous flagellate are linked to suspended particle physical properties

International Nuclear Information System (INIS)

Boenigk, Jens; Wiedlroither, Anneliese; Pfandl, Karin

2005-01-01

Many dissolved substances attach easily to sediment particles. In the presence of suspended sediments bioavailability of dissolved substances is therefore, usually reduced and clays are even applied to 'wash' natural waters upon pollution. In organisms which feed on food organisms in the size range of these suspended sediment particles, however, bioavailability of such substances may even increase. For microorganisms the interaction with dissolved substances and suspended sediment particles so far has hardly been investigated. We specifically tested: (1) the importance of suspended particles as an uptake route for dissolved substances; and (2) the significance of particle surface properties, i.e. surface load and mineralogy. As a model system we used an axenically cultured strain of a widespread and often abundant flagellate ('Spumella-like' flagellate strain JBM10). We tested the toxicity of cadmium (II) and mercury (II) as well as availability of dissolved organic matter (DOM) in the absence as well as in the presence of different natural clays, i.e. a kaolinite, a montmorillonite, and a mixed clay, and of artificial silicate particles of different surface charge. When applied separately the presence of the heavy metals cadmium and mercury as well as of suspended particles negatively affected the investigated flagellate but nutritive organics supported growth of the investigated flagellate. Toxic stress response comprises behavioral changes including enhanced swimming activity and stress egestion of ingested particles and was generally similar for a variety of different flagellate species. In combination with suspended particles, the respective effect of trace metals and nutritive substances decreased. Regarding the particle quality, cadmium toxicity increased with increasingly negative surface charge, i.e. increasing surface density of silanol groups (Pearson's product moment, P = 0.005). For mercury particle mineralogy still had a significant effect (P < 0

Generation of hydroxyl radicals by urban suspended particulate air matter. The role of iron ions

Science.gov (United States)

Valavanidis, Athanasios; Salika, Anastasia; Theodoropoulou, Anna

Recent epidemiologic studies showed statistical associations between particulate air pollution in urban areas and increased morbidity and mortality, even at levels well within current national air quality standards. Inhalable particulate matter (PM 10) can penetrate into the lower airways where they can cause acute and chronic lung injury by generating toxic oxygen free radicals. We tested inhalable total suspended particulates (TSP) from the Athens area, diesel and gasoline exhaust particles (DEP and GED), and urban street dusts, by Electron Paramagnetic Resonance (EPR). All particulates can generate hydroxyl radicals (HO ṡ), in aqueous buffered solutions, in the presence of hydrogen peroxide. Results showed that oxidant generating activity is related with soluble iron ions. Leaching studies showed that urban particulate matter can release large amounts of Fe 3+ and lesser amounts of Fe 2+, as it was shown from other studies. Direct evidence of HO ṡ was confirmed by spin trapping with DMPO and measurement of DMPO-OH adduct by EPR. Evidence was supported with the use of chelator (EDTA), which increases the EPR signal, and the inhibition of the radical generating activity by desferrioxamine or/and antioxidants ( D-mannitol, sodium benzoate).

Biologically Active Organic Matter in Soils of European Russia

Science.gov (United States)

Semenov, V. M.; Kogut, B. M.; Zinyakova, N. B.; Masyutenko, N. P.; Malyukova, L. S.; Lebedeva, T. N.; Tulina, A. S.

2018-04-01

Experimental and literature data on the contents and stocks of active organic matter in 200 soil samples from the forest-tundra, southern-taiga, deciduous-forest, forest-steppe, dry-steppe, semidesert, and subtropical zones have been generalized. Natural lands, agrocenoses, treatments of long-term field experiments (bare fallow, unfertilized and fertilized crop rotations, perennial plantations), and different layers of soil profile are presented. Sphagnum peat and humus-peat soil in the tundra and forest-tundra zones are characterized by a very high content of active organic matter (300-600 mg C/100 g). Among the zonal soils, the content of active organic matter increases from the medium (75-150 mg C/100 g) to the high (150-300 mg C/100 g) level when going from soddy-podzolic soil to gray forest and dark-gray forest soils and then to leached chernozem. In the series from typical chernozem to ordinary and southern chernozem and chestnut and brown semidesert soils, a decrease in the content of active organic matter to the low (35-75 mg C/100 g) and very low (organic matter. Most arable soils are mainly characterized by low or very low contents of active organic matter. In the upper layers of soils, active organic matter makes up 1.2-11.1% of total Corg. The profile distribution of active organic matter in the studied soils coincides with that of Corg: their contents appreciably decrease with depth, except for brown semidesert soil. The stocks of active organic matter vary from 0.4 to 5.4 t/ha in the layer of 0-20 cm and from 1.0 to 12.4/ha in the layer of 0-50 cm of different soil types.

Influence of microorganism content in suspended particles on the particle-water partitioning of mercury in semi-enclosed coastal waters.

Science.gov (United States)

Jang, Jiyi; Kim, Hyunji; Han, Seunghee

2014-02-01

It is known that particle scavenging of mercury (Hg) can be affected by the abundance of particulate organic matter in coastal waters. However, the role of living organic particles in Hg scavenging is not yet completely understood. In this study, we hypothesized that an abundance of living organic particles (i.e., phytoplankton and bacteria) would influence the particle-water partitioning of Hg in coastal waters. Surface seawater samples were collected from eight stations in Gwangyang Bay, Korea, in three seasons (November 2009, April 2010, and October 2010) for the determination of concentrations of suspended particulate matter (including chlorophyll-a and bacteria), and Hg in unfiltered and filtered waters. We found that more Hg partitioned toward particulate matter when phytoplankton biomass, indicated from the chlorophyll-a concentration in a particle, was higher. In the low algal season, when [chlorophyll-a]algae to transfer Hg to marine food chains. © 2013.

Monitoring the effects of disposal of fine sediments from maintenance dredging on suspended particulate matter concentration in the Belgian nearshore area

OpenAIRE

Fettweis, M.; Baeye, M.; Francken, F.; Lauwaert, B.; Van den Eynde, D.; Van Lancker, V.; Martens, C.; Michielsen, T.

2012-01-01

The impact of continuous disposal of fine-grained sediments from maintenance dredging works on the suspended particulate matter concentration in a shallow nearshore turbidity maximum was investigated during dredging experiment (port of Zeebrugge, southern North Sea). Before, during and after the experiment monitoring of SPM concentration using OBS and ADV altimetry was carried out at a location 5 km west of the disposal site. A statistical analysis, based on the concept of populations and sub...

Influence of particle characteristics and organic matter content on the bioavailability and bioaccumulation of pyrene by clams

International Nuclear Information System (INIS)

Verrengia Guerrero, N.R.; Taylor, M.G.; Wider, E.A.; Simkiss, K.

2003-01-01

An experimental model with artificial particles and humic acids describes bioavailability of sediment-bound pyrene to clams. - Hydrophobic chemicals are known to associate with sediment particles including those from both suspended particulate matter and bottom deposits. The complex and variable composition of natural particles makes it very difficult therefore, to predict the bioavailability of sediment-bound contaminants. To overcome these problems we have previously devised a test system using artificial particles, with or without humic acids, for use as an experimental model of natural sediments. In the present work we have applied this experimental technique to investigate the bioavailability and bioaccumulation of pyrene by the freshwater fingernail clam Sphaerium corneum. The uptake and accumulation of pyrene in clams exposed to the chemical in the presence of a sample of natural sediment was also investigated. According to the results obtained, particle surface properties and organic matter content are the key factors for assessing the bioavailability and bioaccumulation of pyrene by clams

A new method for identifying the types of organic matter

International Nuclear Information System (INIS)

Tong Chunhan; Li Guodong

1991-01-01

A new method for dividing the types of organic matter according to V and Ni contents in soluble organic matter determined by NAA is introduced. The research site was an oil-gas field in northeastern China. The type of organic matter is an important parameter in evaluating an oil or a gas field. The conventional organic geochemistry methods will meet unsurmountable difficulties when the maturity of organic matter is high. The method described in this paper can solve the problem. (author) 4 refs.; 1 fig.; 2 tabs

Methods for Determining Organic Matter and Colour in Water

Directory of Open Access Journals (Sweden)

Ramunė Albrektienė

2011-02-01

Full Text Available The article examines different methods for determining organic matter and colour in water. Most of organic compounds in water have a humic substance. These substances frequently form complexes with iron. Humic matter gives water a yellow-brownish colour. Water filtration through conventional sand filters does not remove colour and organic compounds, and therefore complicated water treatment methods shall be applied. The methods utilized for organic matter determination in water included research on total organic carbon, permanganate index and the bichromate number of UV absorption of 254 nm wave length. The obtained results showed the greatest dependence between water colour and permanganate index. However, UV adsorption could be used for organic matter determination during the operation of a water treatment plant and the start-up of plants as easy and fast methods.Article in Lithuanian

Characteristics and sources analysis of riverine chromophoric dissolved organic matter in Liaohe River, China.

Science.gov (United States)

Shao, Tiantian; Song, Kaishan; Jacinthe, Pierre-Andre; Du, Jia; Zhao, Ying; Ding, Zhi; Guan, Ying; Bai, Zhang

2016-12-01

Chromophoric dissolved organic matter (CDOM) in riverine systems can be affected by environmental conditions and land-use, and thus could provide important information regarding human activities in surrounding landscapes. The optical properties of water samples collected at 42 locations across the Liaohe River (LHR, China) watershed were examined using UV-Vis and fluorescence spectroscopy to determine CDOM characteristics, composition and sources. Total nitrogen (TN) and total phosphorus (TP) concentrations at all sampling sites exceeded the GB3838-2002 (national quality standards for surface waters, China) standard for Class V waters of 2.0 mg N/L and 0.4 mg P/L respectively, while trophic state index (TSI M ) indicated that all the sites investigated were mesotrophic, 64% of which were eutrophic at the same time. Redundancy analysis showed that total suspended matter (TSM), dissolved organic carbon (DOC), and turbidity had a strong correlation with CDOM, while the other parameters (Chl a, TN, TP and TSI M ) exhibited weak correlations with CDOM absorption. High spectral slope values and low SUVA254 (the specific UV absorption) values indicated that CDOM in the LHR was primarily comprised of low molecular weight organic substances. Analysis of excitation-emission matrices contour plots showed that CDOM in water samples collected from upstream locations exhibited fulvic-acid-like characteristics whereas protein-like substances were most likely predominant in samples collected in estuarine areas and downstream from large cities. These patterns were interpreted as indicative of water pollution from urban and industrial activities in several downstream sections of the LHR watershed.

Measuring organic matter in Everglades wetlands and the Everglades Agricultural Area

Energy Technology Data Exchange (ETDEWEB)

Wright, Alan L. [Univ. of Florida, Gainesville, FL (United States); Hanlon, Edward A. [Univ. of Florida, Gainesville, FL (United States)

2015-01-01

Here, organic matter is a complex material that represents the long-term decay products from plants and other organisms in the soil. When organic matter is allowed to build up in a soil, the soil color at the surface usually turns a darker color, often with a red or brown hue. Typically in Florida mineral soils, organic matter content is quite low, within the range of 1 to 5%. However, in some soils that remain flooded for most of the year, organic matter can build up with time and actually become the soil. Such is the case for the organic soils, or histosols, found in southern Florida. These organic soils comprise much of the Water Conservation Areas, Everglades National Park (ENP), Big Cypress Basin, and the Everglades Agricultural Area (EAA). It is important to document organic matter accumulation in the Everglades to gauge the effectiveness of wetland creation and succession. For the EAA, the drained soils lose organic matter due to oxidation, so measurement of the organic matter content of these soils over the course of time indicates the oxidation potential and mineral incorporation from bedrock. Due to the wide diversity of soil types and methods of measuring soil organic matter, there is a need to devise a more universal method applicable to many types of histosols in south Florida. The intent of this publication is: 1.To describe a simple laboratory method for determining the organic matter content of the organic soils of southern Florida and demonstrate the importance of using this new procedure for improved accuracy and precision; 2.To utilize this updated laboratory procedure for field sites across Everglades wetlands and the EAA; and 3. To recommend this procedure be used by growers, state and federal agencies, and university and agency researchers dealing with the management of organic soils in southern Florida. Growers can use this improvement to organic matter measurement to keep lab testing costs low while getting a better, more quantitative

Mercury dilution by autochthonous organic matter in a fertilized mangrove wetland.

Science.gov (United States)

Machado, Wilson; Sanders, Christian J; Santos, Isaac R; Sanders, Luciana M; Silva-Filho, Emmanoel V; Luiz-Silva, Wanilson

2016-06-01

A dated sediment core from a highly-fertilized mangrove wetland located in Cubatão (SE Brazil) presented a negative correlation between mercury (Hg) and organic carbon contents. This is an unusual result for a metal with well-known affinity to organic matter. A dilution of Hg concentrations by autochthonous organic matter explained this observation, as revealed by carbon stable isotopes signatures (δ(13)C). Mercury dilution by the predominant mangrove-derived organic matter counterbalanced the positive influences of algal-derived organic matter and clay contents on Hg levels, suggesting that deleterious effects of Hg may be attenuated. Considering the current paradigm on the positive effect of organic matter on Hg concentrations in coastal sediments and the expected increase in mangrove organic matter burial due to natural and anthropogenic stimulations of primary production, predictions on the influences of organic matter on Hg accumulation in mangrove wetlands deserve caution. Copyright © 2016 Elsevier Ltd. All rights reserved.

Soil organic matter dynamics and the global carbon cycle

International Nuclear Information System (INIS)

Post, W.M.; Emanuel, W.R.; King, A.W.

1992-01-01

The large size and potentially long residence time of the soil organic matter pool make it an important component of the global carbon cycle. Net terrestrial primary production of about 60 Pg C·yr -1 is, over a several-year period of time, balanced by an equivalent flux of litter production and subsequent decomposition of detritus and soil organic matter. We will review many of the major factors that influence soil organic matter dynamics that need to be explicitly considered in development of global estimates of carbon turnover in the world's soils. We will also discuss current decomposition models that are general enough to be used to develop a representation of global soil organic matter dynamics

Effects of organic matter and ageing on the bioaccessibility of arsenic

International Nuclear Information System (INIS)

Meunier, Louise; Koch, Iris; Reimer, Kenneth J.

2011-01-01

Arsenic-contaminated soils may pose a risk to human health. Redevelopment of contaminated sites may involve amending soils with organic matter, which potentially increases arsenic bioaccessibility. The effects of ageing on arsenic-contaminated soils mixed with peat moss were evaluated in a simulated ageing period representing two years, during which arsenic bioaccessibility was periodically measured. Significant increases (p = 0.032) in bioaccessibility were observed for 15 of 31 samples tested, particularly in comparison with samples originally containing >30% bioaccessible arsenic in soils naturally rich in organic matter (>25%). Samples where percent arsenic bioaccessibility was unchanged with age were generally poor in organic matter (average 7.7%) and contained both arsenopyrite and pentavalent arsenic forms that remained unaffected by the organic matter amendments. Results suggest that the addition of organic matter may lead to increases in arsenic bioaccessibility, which warrants caution in the evaluation of risks associated with redevelopment of arsenic-contaminated land. - Highlights: → Adding organic matter to contaminated soils may increase arsenic bioaccessibility. → Ageing soils with >25% organic matter can lead to increased arsenic bioaccessibility. → No changes in arsenic bioaccessibility for soils poor in organic matter (mean 7.7%). → No changes in arsenic bioaccessibility for samples containing arsenopyrite. → Organic matter in soil may favour oxidation of trivalent arsenic to pentavalent form. - Adding organic carbon may increase arsenic bioaccessibility, especially in samples originally containing >30% bioaccessible arsenic in organic carbon-rich soils (>25%).

Behaviour of organic matters in uranium ore processing

International Nuclear Information System (INIS)

Wu Sanmin

1991-01-01

The oxidation-reduction behaviour of organic matters in the course of oxidation roasting, acid leaching and alkali leaching, the regeneration of humic acid and the consumption of reagents are described. The mineralogical characteristics of the organic matter samples were studied. The results show that its organic matter rich in volatile carbon and with the shorter evolutionary process and lower association is easily oxidized with higher consumption of oxidant during its acid leaching; it is easily oxidized with forming humic acid during alkali leaching; and pretreating it by oxidation roasting is beneficial to the oxidation of uranium. On the contrary, the organic matter rich in fixed carbon, and with longer evolutionary process and higher association is difficultly oxidized with lower consumption of oxidant during its acid leaching; it is difficult to regenerate humic acid for it during alkali leaching; and the uranium can be easily reduced and the leaching performance of uranium can be lowered

Simulation of the transport of suspended particulate matter in the Rio de la Plata

Energy Technology Data Exchange (ETDEWEB)

Hausstein, H.

2008-11-06

Numerical simulations of the transport of Suspended Particulate Matter in the Rio de la Plata estuary were performed with a three dimensional model for coastal waters driven by wave sand currents. Aturbulence based flocculation approach is implemented to the model. The model is for the first time applied under heavy conditions, since the Rio de la Plata has discharges up to 25000 m{sup 3}/s and SPM concentrations up to 300-400 mg/l. Such concentrations are also difficult to compute from satellite measurements. SeaWiFs satellite images served for the validation of the model results. The model is able to reproduce the shape and the position of the front as well as the zone of the turbidity maximum. It also identifies the zones of erosion and deposition which is of significant importance because of the dense ship traffic along the navigational channels towards Buenos Aires and the cities upstream the rivers. (orig.)

Characterization of dissolved organic matter in fogwater by excitation-emission matrix fluorescence spectroscopy

Science.gov (United States)

Birdwell, J.E.; Valsaraj, K.T.

2010-01-01

Dissolved organic matter (DOM) present in fogwater samples collected in southeastern Louisiana and central-eastern China has been characterized using excitation-emission matrix fluorescence spectroscopy. The goal of the study was to illustrate the utility of fluorescence for obtaining information on the large fraction of organic carbon in fogwaters (typically >40% by weight) that defies characterization in terms of specific chemical compounds without the difficulty inherent in obtaining sufficient fogwater volume to isolate DOM for assessment using other spectroscopic and chemical analyses. Based on the findings of previous studies using other characterization methods, it was anticipated that the unidentified organic carbon fraction would have characteristic peaks associated with humic substances and fluorescent amino acids. Both humic- and protein-like fluorophores were observed in the fogwater spectra and fluorescence-derived indices for the fogwater had similar values to those of soil and sediment porewater. Greater biological character was observed in samples with higher organic carbon concentrations. Fogwaters are shown to contain a mixture of terrestrially- and microbially-derived fluorescent organic material, which is expected to be derived from an array of different sources, such as suspended soil and dust particles, biogenic emissions and organic substances generated by atmospheric processes. The fluorescence results indicate that much of the unidentified organic carbon present in fogwater can be represented by humic-like and biologically-derived substances similar to those present in other aquatic systems, though it should be noted that fluorescent signatures representative of DOM produced by atmospheric processing of organic aerosols may be contributing to or masked by humic-like fluorophores. ?? 2010.

Geospatial approach towards enumerative analysis of suspended sediment concentration for Ganges-Brahmaputra Bay

Science.gov (United States)

Pandey, Palak; Kunte, Pravin D.

2016-10-01

This study presents an easy, modular, user-friendly, and flexible software package for processing of Landsat 7 ETM and Landsat 8 OLI-TIRS data for estimating suspended particulate matter concentrations in the coastal waters. This package includes 1) algorithm developed using freely downloadable SCILAB package, 2) ERDAS Models for iterative processing of Landsat images and 3) ArcMAP tool for plotting and map making. Utilizing SCILAB package, a module is written for geometric corrections, radiometric corrections and obtaining normalized water-leaving reflectance by incorporating Landsat 8 OLI-TIRS and Landsat 7 ETM+ data. Using ERDAS models, a sequence of modules are developed for iterative processing of Landsat images and estimating suspended particulate matter concentrations. Processed images are used for preparing suspended sediment concentration maps. The applicability of this software package is demonstrated by estimating and plotting seasonal suspended sediment concentration maps off the Bengal delta. The software is flexible enough to accommodate other remotely sensed data like Ocean Color monitor (OCM) data, Indian Remote Sensing data (IRS), MODIS data etc. by replacing a few parameters in the algorithm, for estimating suspended sediment concentration in coastal waters.

Circulation and suspended particulate matter transport in a tidally dominated estuary: caravelas estuary, Bahia, Brazil

Directory of Open Access Journals (Sweden)

Carlos Augusto França Schettini

2010-03-01

Full Text Available The circulation and transport of suspended particulate matter in the Caravelas Estuary are assessed. Nearly-synoptic hourly hydrographic, current (ADCP velocity and volume transport and suspended particulate matter data were collected during a full semidiurnal spring tide, on the two transects Boca do Tomba and Barra Velha and on longitudinal sections at low and high tide. On the first transect the peak ebb currents (-1.5 ms-1 were almost twice as strong as those of the wider and shallow Barra Velha inlet (-0.80 ms-1 and the peak flood currents were 0.75 and 0.60 ms-1, respectively. Due to the strong tidal currents both inlets had weak vertical salinity stratification and were classified with the Stratification-circulation Diagram as Type 2a (partially mixed-weakly stratified and Type 1a (well mixed. Volume transports were very close, ranging from -3,500 to 3,100 m³s-1 at the ebb and flood, respectively, with a residual -630 m³s-1. The concentration of the suspended particulate matter was closely related to the tidal variation and decreased landwards from 50 mg.L-1 at the estuary mouth, to 10 mg.L-1 at distances of 9 and 16 km for the low and high tide experiments, respectively. The total residual SPM transport was out of the estuary at rates of -18 tons per tidal cycle.A circulação e o transporte de material particulado em suspensão no Estuário de Caravelas são pesquisados. Dados quase-sinóticos hidrográficos, de correntes (velocidade e transporte de volume com ADCP e de material particulado em suspensão, foram medidos em intervalos horários durante um ciclo semidiurno de maré de sizígia, em duas seções transversais na Boca do Tomba e na Barra Velha e também em seções longitudinais na baixa-mar e na preamar. Na primeira transversal as correntes máximas de vazante (-1,50 m s-1 foram quase duas vezes mais intensas do que na seção transversal mais larga e rasa Barra Velha, (-0,80 m s-1 e as maiores velocidades das correntes de

Organic Matter Dynamics in Soils Regenerating from Degraded ...

African Journals Online (AJOL)

The area of secondary forest (SF) regenerating from degraded abandoned rubber (Hevea brasiliensis) plantation is increasing in the rainforest zone of south southern Nigeria; however, the build-up of soil organic matter following abandonment is not well understood. This study examined the build-up of soil organic matter in ...

Sedimentary organic matter sources, benthic consumption and burial in west Spitsbergen fjords - Signs of maturing of Arctic fjordic systems?

Science.gov (United States)

Zaborska, Agata; Włodarska-Kowalczuk, Maria; Legeżyńska, Joanna; Jankowska, Emilia; Winogradow, Aleksandra; Deja, Kajetan

2018-04-01

Mature ecosystems sequester little organic carbon (Corg) in sediments, as the complex and effective food webs consume most available organic matter within the water column and sediment, in contrast to young systems, where a large proportion of Corg is buried in deeper sediment layers. In this paper we hypothesize that "warmer" Atlantic water influenced fjord exhibits the 'mature' system features as compared to "cooler" Arctic water influenced fjord. Corg concentrations, sources and burial rates, as well as macrobenthic community standing stocks, taxonomic and functional composition and carbon demand, were compared in two west Spitsbergen fjords that are to different extents influenced by Atlantic water and can be treated as representing a cold one (Hornsund) and a warm one (Kongsfjorden). Water, sediments and macrofauna were collected at three stations in the central basin of each fjord. Corg, Ntot, δ13Corg and δ15N were measured in suspended matter, sediment cores and possible organic matter sources. The composition of sources of sedimentary organic matter was modeled by Mix-SIAR Bayesian stable isotope mixing models. The 210Pb method was used to calculate sediment accumulation rates, Corg accumulation and burial rates. The sedimentary Corg concentration and accumulation rate were larger in Hornsund than in Kongsfjorden. The contributions of pelagic sources to the Corg in sediments were similar in both fjords, macroalgal detritus had a higher importance in Kongsfjorden, while terrestrial sources were more important in Hornsund. Similar density and species richness were noted in both fjords, but higher biomass, individual biomass, production and carbon demand of benthic communities were noted in Kongsfjorden despite the lower amounts of Corg in sediments, indicating that macrobenthos responds to quality rather than quantity of available food. Subsurface tube-building conveyer belt detritus feeders (maldanids and oweniids) were responsible for higher standing

Removal of Cs{sup +}, Sr{sup 2+}, and Co{sup 2+} ions from the mixture of organics and suspended solids aqueous solutions by zeolites

Energy Technology Data Exchange (ETDEWEB)

Fang, Xiang Hong; Fang, Fang; Lu, Chun Hai [College of Nuclear Technology and Automation Engineering, Chengdu University of Technology, Chengdu (China); Zheng, Lei [Southwest University of Science and Technology, Key Laboratory of Solid Waste Treatment and Resource Recycle, Ministry of Education, Mianyang (China)

2017-04-15

Serving as an excellent adsorbent and inorganic ion exchanger in the water purification field, zeolite 4A has in this work presented a strong capability for purifying radioactive waste, such as Sr{sup 2+}, Cs{sup +}, and Co{sup 2+} in water. During the processes of decontamination and decommissioning of suspended solids and organics in low-level radioactive wastewater, the purification performance of zeolite 4A has been studied. Under ambient temperature and neutral condition, zeolite 4A absorbed simulated radionuclides such as Sr{sup 2+}, Cs{sup +}, and Co{sup 2+} with an absorption rate of almost 90%. Additionally, in alkaline condition, the adsorption percentage even approached 98.7%. After conducting research on suspended solids and organics of zeolite 4A for the treatment of radionuclides, it was found that the suspended clay was conducive to absorption, whereas the absorption of organics in solution was determined by the species of radionuclides and organics. Therefore, zeolite 4A has considerable potential in the treatment of radioactive wastewater.

Analytic study of organic matters in Lodeve uranium ore

International Nuclear Information System (INIS)

Campuzano, E.J.

1981-01-01

Exploitation of uranium in the Permian basin of Lodeve is difficult because of simultaneous extraction of organic matters which are found, in small proportion, in ammonium diuranate and a supplementary purification is required. Available information on natural organic matters are briefly reviewed. Natural organic matters contained in the Lodeve uranium ore processing fluid is separated and fractionated. Physicochemical properties of ligands in each fraction are studied. The existence of bonds between these ligands and dissolved uranium is experimentally demonstrated [fr

Tiny is mighty: seagrass beds have a large role in the export of organic material in the tropical coastal zone.

Science.gov (United States)

Gillis, Lucy G; Ziegler, Alan D; van Oevelen, Dick; Cathalot, Cecile; Herman, Peter M J; Wolters, Jan W; Bouma, Tjeerd J

2014-01-01

Ecosystems in the tropical coastal zone exchange particulate organic matter (POM) with adjacent systems, but differences in this function among ecosystems remain poorly quantified. Seagrass beds are often a relatively small section of this coastal zone, but have a potentially much larger ecological influence than suggested by their surface area. Using stable isotopes as tracers of oceanic, terrestrial, mangrove and seagrass sources, we investigated the origin of particulate organic matter in nine mangrove bays around the island of Phuket (Thailand). We used a linear mixing model based on bulk organic carbon, total nitrogen and δ13C and δ15N and found that oceanic sources dominated suspended particulate organic matter samples along the mangrove-seagrass-ocean gradient. Sediment trap samples showed contributions from four sources oceanic, mangrove forest/terrestrial and seagrass beds where oceanic had the strongest contribution and seagrass beds the smallest. Based on ecosystem area, however, the contribution of suspended particulate organic matter derived from seagrass beds was disproportionally high, relative to the entire area occupied by mangrove forests, the catchment area (terrestrial) and seagrass beds. The contribution from mangrove forests was approximately equal to their surface area, whereas terrestrial contributions to suspended organic matter under contributed compared to their relative catchment area. Interestingly, mangrove forest contribution at 0 m on the transects showed a positive relationship with the exposed frontal width of the mangrove, indicating that mangrove forest exposure to hydrodynamic energy may be a controlling factor in mangrove outwelling. However we found no relationship between seagrass bed contribution and any physical factors, which we measured. Our results indicate that although seagrass beds occupy a relatively small area of the coastal zone, their role in the export of organic matter is disproportional and should be

Effect of Feeding Schedule on Fractionated Particulate Matter Distribution in Rooster House

Science.gov (United States)

The persistence and long life expectancy of ammonia, odors and toxic pollutants from poultry houses may be due to the ability of suspended particulate matters (SPM) to serve as carriers for odorous compounds such as ammonium ions and volatile organic compounds. SPM is generated from the feed, anima...

Aggregation of montmorillonite and organic matter in aqueous media containing artificial seawater

Directory of Open Access Journals (Sweden)

Kim Jinwook

2009-01-01

Full Text Available Abstract Background The dispersion-aggregation behaviors of suspended colloids in rivers and estuaries are affected by the compositions of suspended materials (i.e., clay minerals vs. organic macromolecules and salinity. Laboratory experiments were conducted to investigate the dispersion and aggregation mechanisms of suspended particles under simulated river and estuarine conditions. The average hydrodynamic diameters of suspended particles (representing degree of aggregation and zeta potential (representing the electrokinetic properties of suspended colloids and aggregates were determined for systems containing suspended montmorillonite, humic acid, and/or chitin at the circumneutral pH over a range of salinity (0 – 7.2 psu. Results The montmorillonite-only system increased the degree of aggregation with salinity increase, as would be expected for suspended colloids whose dispersion-aggregation behavior is largely controlled by the surface electrostatic properties and van der Waals forces. When montmorillonite is combined with humic acid or chitin, the aggregation of montmorillonite was effectively inhibited. The surface interaction energy model calculations reveal that the steric repulsion, rather than the increase in electronegativity, is the primary cause for the inhibition of aggregation by the addition of humic acid or chitin. Conclusion These results help explain the range of dispersion-aggregation behaviors observed in natural river and estuarine systems. It is postulated that the composition of suspended particles, specifically the availability of steric polymers such as those contained in humic acid, determine whether the river suspension is rapidly aggregated and settled or remains dispersed in suspension when it encounters increasingly saline environments of estuaries and oceans.

Environmental toxicology: Acute effects of suspended particulate matter (dust on hematological indices of albino rats

Directory of Open Access Journals (Sweden)

V.O. Ogugbuaja

2004-12-01

Full Text Available The elemental contents of suspended particulate matter (dust samples from Maiduguri, Nigeria, were determined which showed appreciably high levels for especially Pb, Fe, Cu, Zn, K, Ca, and. Na. Wister albino rats were exposed to graded doses of phosphate buffered saline carried dust particles. The hematological indices of the exposed rats were examined on days 10, 20, 30, and 60 post administrations. White blood cell, red blood cell and hemoglobin counts peaked between days 20 and 30. This observation was markedly so for the higher doses, 1000 and 2000 mg/kg, in contrast to the 500 mg/kg dose. The platelet count however indicated a gradual increase within the study period. Observed changes for these indices from the control values were found significant at 99% confidence level. Possible inhalatory problems are thus anticipated from prolonged accumulation of the dust in the respiratory system.

Chemical Structure of Insoluble Organic Matter of Meteorites

Science.gov (United States)

Derenne, S.; Robert, F.; Binet, L.; Gourier, D.; Rouzaud, J.-N.; Largeau, C.

A detailed knowledge of the insoluble organic matter (IOM) of the meteorites is essential to estimate to what extent the interstellar organic matter was preserved during the formation of the solar system and to decipher the synthetic pathways of this matter in space. Although predominant, the insoluble organic fraction has been much less extensively studied than soluble one due to specific analytical difficulties. The present work reports the examination of the IOM of two carbonaceous meteorites, Orgueil and Murchison through a number of various spectroscopic and microscopic methods, i. e. XANES for sulphur, carbon and nitrogen, solid state 13C NMR, electron paramagnetic resonance, electron nuclear double resonance and high resolution transmission electron microscopy.

Organic carbon organic matter and bulk density relationships in arid ...

African Journals Online (AJOL)

Soil organic matter (SOM) and soil organic carbon (SOC) constitute usually a small portion of soil, but they are one of the most important components of ecosystems. Bulk density (dB or BD) value is necessary to convert organic carbon (OC) content per unit area. Relationships between SOM, SOC and BD were established ...

Temperature sensitivity of respiration scales with organic matter recalcitrance

Science.gov (United States)

Craine, J. M.; Fierer, N.; McLauchlan, K. K.

2010-12-01

Microbial decomposition of soil organic matter is a key process in determining the carbon sequestration potential of ecosystems and carbon fluxes to the atmosphere. Since microbial decomposition is highly sensitive to short-term changes in temperature, predicting the temperature sensitivity of microbial decomposition is critical to predicting future atmospheric carbon dioxide concentrations and feedbacks to anthropogenic warming. Fundamental principles of enzyme kinetics, embodied in the carbon-quality temperature hypothesis, predict that the temperature sensitivity of microbial decomposition should increase with increasing biochemical recalcitrance of a substrate. To test the generality of this principle, we measured the temperature sensitivity of microbial respiration of soil organic matter with serial short-term temperature manipulations over 365 days for 28 North American soils. When joined with data from similar studies that represent a wide variety of contrasts, we show that the temperature sensitivity of organic matter decomposition scales with biochemical recalcitrance. With physico-chemical protection likely an important covariate for relating plant and soil organic matter decomposition scalars, biochemically recalcitrant organic matter is highly susceptible to short-term increases in temperature, a key link in predicting the effects of warming on carbon cycling.

d¹³C and d¹⁵N dynamics of particulate organic matter in freshwater and brackish waters of the Scheldt estuary

DEFF Research Database (Denmark)

De Brabandere, Loreto; Dehairs, F.; Van Damme, S.

2002-01-01

the growth season reflects the 15N enrichment of the ambient NH4 + pool induced by nitrification and NH4+ uptake. Zooplankton in the mesohaline section of the river was consistently enriched in 15N relative to suspended matter but followed its seasonal trend. During summer and autumn the isotopic offset...... matter in the oligohaline and mesohaline section increased compared to the 1970s, probably because today nitrification, which enriches the NH4+ pool in 15N, starts earlier in the season. For summer, the discrepancy between present-day suspended matter d15N values and those observed in the 1970s was even...

In-situ partitioning and bioconcentration of polycyclic aromatic hydrocarbons among water, suspended particulate matter, and fish in the Dongjiang and Pearl Rivers and the Pearl River Estuary, China

International Nuclear Information System (INIS)

Li, Haiyan; Lu, Lei; Huang, Wen; Yang, Juan; Ran, Yong

2014-01-01

Highlights: • PAHs are relatively higher in marine fish than in freshwater fish. • PAHs respectively show significant correlations with DOC, POC, and Chl a. • The log K oc for PAHs is one order magnitude higher than the predicted. • The log BCF values in fish and their tissues are nonlinear in respect to log K ow . • Lipid is related to PAHs in freshwater fish, but not in marine fishes. - Abstract: The partitioning and bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) in water, suspended particulate matter (SPM), and fish samples from the Dongjiang River (DR), Pearl River (PR), and the Pearl River Estuary (PRE) were examined. Although PAHs are much lower in PRE than in DR or PR, PAHs in some fish species are significantly higher in PRE than in DR or PR. Aqueous or particulate PAHs respectively show significant correlations with dissolved organic carbon, particulate organic matter, and chlorophyll a, suggesting that biological pumping effect regulates their distribution. The in situ partitioning coefficients (log K oc ) for PAHs are one order magnitude higher than the empirical log K oc –log K ow correlation. The bioconcentration factor (BCF) is slightly higher for the marine fish than for the freshwater fish. The above phenomena indicate that BCF may vary due to the diversity of fish species, feeding habits, and metabolism of PAHs in fish

Organic matter dynamics and N mineralization in grassland soils

NARCIS (Netherlands)

Hassink, J.

1995-01-01

The aims of this study are i) to improve our understanding of the interactions between soil texturelsoil structure, soil organic matter, soil biota and mineralization in grassland soils, ii) to develop a procedure that yields soil organic matter fractions that can be determined directly

Compound-specific C- and H-isotope compositions of enclosed organic matter in carbonate rocks: Implications for source identification of sedimentary organic matter and paleoenvironmental reconstruction

International Nuclear Information System (INIS)

Xiong Yongqiang; Wang Yanmei; Wang Yongquan; Xu Shiping

2007-01-01

The Bohai Bay Basin is one of the most important oil-producing provinces in China. Molecular organic geochemical characteristics of Lower Paleozoic source rocks in this area have been investigated by analyzing chemical and isotopic compositions of solvent extracts and acid-released organic matter from the Lower Paleozoic carbonate rocks in the Jiyang Sub-basin of the Bohai Bay Basin. The results indicate that enclosed organic matter in carbonate rocks has not been recognizably altered by post-depositional processes. Two end-member compositions are suggested for early organic matter trapped in the Lower Paleozoic carbonate rocks: (1) a source dominated by aquatic organisms and deposited in a relatively deep marine environment and (2) a relatively high saline, evaporative marine depositional environment. In contrast, chemical and isotopic compositions of solvent extracts from these Lower Paleozoic carbonate rocks are relatively complicated, not only inheriting original characteristics of their precursors, but also overprinted by various post-depositional alterations, such as thermal maturation, biodegradation and mixing. Therefore, the integration of both organic matter characteristics can provide more useful information on the origin of organic matter present in carbonate rocks and the environments of their deposition

Compound-specific C- and H-isotope compositions of enclosed organic matter in carbonate rocks: Implications for source identification of sedimentary organic matter and paleoenvironmental reconstruction

Energy Technology Data Exchange (ETDEWEB)

Xiong Yongqiang [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China)], E-mail: xiongyq@gig.ac.cn; Wang Yanmei; Wang Yongquan; Xu Shiping [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China)

2007-11-15

The Bohai Bay Basin is one of the most important oil-producing provinces in China. Molecular organic geochemical characteristics of Lower Paleozoic source rocks in this area have been investigated by analyzing chemical and isotopic compositions of solvent extracts and acid-released organic matter from the Lower Paleozoic carbonate rocks in the Jiyang Sub-basin of the Bohai Bay Basin. The results indicate that enclosed organic matter in carbonate rocks has not been recognizably altered by post-depositional processes. Two end-member compositions are suggested for early organic matter trapped in the Lower Paleozoic carbonate rocks: (1) a source dominated by aquatic organisms and deposited in a relatively deep marine environment and (2) a relatively high saline, evaporative marine depositional environment. In contrast, chemical and isotopic compositions of solvent extracts from these Lower Paleozoic carbonate rocks are relatively complicated, not only inheriting original characteristics of their precursors, but also overprinted by various post-depositional alterations, such as thermal maturation, biodegradation and mixing. Therefore, the integration of both organic matter characteristics can provide more useful information on the origin of organic matter present in carbonate rocks and the environments of their deposition.

Removal of antibiotics from water in the coexistence of suspended particles and natural organic matters using amino-acid-modified-chitosan flocculants: A combined experimental and theoretical study

International Nuclear Information System (INIS)

Jia, Shuying; Yang, Zhen; Ren, Kexin; Tian, Ziqi; Dong, Chang; Ma, Ruixue; Yu, Ge; Yang, Weiben

2016-01-01

Highlights: • Novel amino-acid-modified-chitosan flocculants are employed to remove antibiotics. • Effects of different structures of amino acids and antibiotics are investigated. • Correlation analysis shows coexisted kaolin and HA have synergistic removal effect. • Theoretical DFT calculation clarifies the interactions in molecular level. - Abstract: Contamination of trace antibiotics is widely found in surface water sources. This work delineates removal of trace antibiotics (norfloxacin (NOR), sulfadiazine (SDZ) or tylosin (TYL)) from synthetic surface water by flocculation, in the coexistence of inorganic suspended particles (kaolin) and natural organic matter (humic acid, HA). To avoid extra pollution caused by petrochemical products-based modification reagents, environmental-friendly amino-acid-modified-chitosan flocculants, Ctrp and Ctyr, with different functional aromatic-rings structures were employed. Jar tests at various pHs exhibited that, Ctyr, owning phenol groups as electron donors, was favored for elimination of cationic NOR (∼50% removal; optimal pH: 6; optimal dosage: 4 mg/L) and TYL (∼60% removal; optimal pH: 7; optimal dosage: 7.5 mg/L), due to π–π electron donator-acceptor (EDA) effect and unconventional H-bonds. Differently, Ctrp with indole groups as electron acceptor had better removal rate (∼50%) of SDZ anions (electron donator). According to correlation analysis, the coexisted kaolin and HA played positive roles in antibiotics’ removal. Detailed pairwise interactions in molecular level among different components were clarified by spectral analysis and theoretical calculations (density functional theory), which are important for both the structural design of new flocculants aiming at targeted contaminants and understanding the environmental behaviors of antibiotics in water.

Removal of antibiotics from water in the coexistence of suspended particles and natural organic matters using amino-acid-modified-chitosan flocculants: A combined experimental and theoretical study

Energy Technology Data Exchange (ETDEWEB)

Jia, Shuying [School of Chemistry and Materials Science, Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing Normal University, Nanjing 210023 (China); Yang, Zhen, E-mail: yangzhen@njnu.edu.cn [School of Chemistry and Materials Science, Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing Normal University, Nanjing 210023 (China); Ren, Kexin [School of Chemistry and Materials Science, Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing Normal University, Nanjing 210023 (China); Tian, Ziqi [Department of Chemistry, University of California, Riverside, CA 92521 (United States); Dong, Chang; Ma, Ruixue; Yu, Ge [School of Chemistry and Materials Science, Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing Normal University, Nanjing 210023 (China); Yang, Weiben, E-mail: yangwb007@njnu.edu.cn [School of Chemistry and Materials Science, Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing Normal University, Nanjing 210023 (China)

2016-11-05

Highlights: • Novel amino-acid-modified-chitosan flocculants are employed to remove antibiotics. • Effects of different structures of amino acids and antibiotics are investigated. • Correlation analysis shows coexisted kaolin and HA have synergistic removal effect. • Theoretical DFT calculation clarifies the interactions in molecular level. - Abstract: Contamination of trace antibiotics is widely found in surface water sources. This work delineates removal of trace antibiotics (norfloxacin (NOR), sulfadiazine (SDZ) or tylosin (TYL)) from synthetic surface water by flocculation, in the coexistence of inorganic suspended particles (kaolin) and natural organic matter (humic acid, HA). To avoid extra pollution caused by petrochemical products-based modification reagents, environmental-friendly amino-acid-modified-chitosan flocculants, Ctrp and Ctyr, with different functional aromatic-rings structures were employed. Jar tests at various pHs exhibited that, Ctyr, owning phenol groups as electron donors, was favored for elimination of cationic NOR (∼50% removal; optimal pH: 6; optimal dosage: 4 mg/L) and TYL (∼60% removal; optimal pH: 7; optimal dosage: 7.5 mg/L), due to π–π electron donator-acceptor (EDA) effect and unconventional H-bonds. Differently, Ctrp with indole groups as electron acceptor had better removal rate (∼50%) of SDZ anions (electron donator). According to correlation analysis, the coexisted kaolin and HA played positive roles in antibiotics’ removal. Detailed pairwise interactions in molecular level among different components were clarified by spectral analysis and theoretical calculations (density functional theory), which are important for both the structural design of new flocculants aiming at targeted contaminants and understanding the environmental behaviors of antibiotics in water.

Effects of effluent organic matter characteristics on the removal of bulk organic matter and selected pharmaceutically active compounds during managed aquifer recharge: Column study

KAUST Repository

Maeng, Sungkyu; Sharma, Saroj K.; Abel, Chol D T; Magic-Knezev, Aleksandra; Song, Kyungguen; Amy, Gary L.

2012-01-01

Soil column experiments were conducted to investigate the effects of effluent organic matter (EfOM) characteristics on the removal of bulk organic matter (OM) and pharmaceutically active compounds (PhACs) during managed aquifer recharge (MAR

Observational evidence for turbulent effects on total suspended matter within the Pearl River plume

Science.gov (United States)

Chunhua, Qiu; Danyi, Su; Huabin, Mao; Jiaxue, Wu; Yongsheng, Cui; Dongxiao, Wang

2017-12-01

We observed the structure of the Pearl River plume and its turbulent characteristics, and investigated the turbulent effect on total suspended matter (TSM) within its ;far-field; region, based on in situ and satellite data collected in June 2015. A significant northeastward plume was created under southern monsoonal conditions. The in situ data provided the width, depth, and velocity of the plume, as inferred by salinity. Weaker turbulence occurred at the front surface position than in the plume zone. Stronger turbulence induced greater turbidity in the bottom boundary layer; however, the surface mixed layer differed. By estimating the turbidity budget, we found the lateral fluxes term was the largest term in the plume, turbulent fluxes comprised the second largest term, and the settling terms comprised the smallest term. We quantified the turbulent mechanisms and found that stronger river discharge induced greater TSM turbidity. Tidal and buoyancy fluxes had minor regulatory effects on TSM. Our observations suggest that TSM in the ;far field; region originated from the Pearl River and the coastal region.

Exposure to carbon monoxide, respirable suspended particulates, and volatile organic compounds while commuting by bicycle

International Nuclear Information System (INIS)

Bevan, M.A.J.; Proctor, C.J.; Baker-Rogers, J.; Warren, N.D.

1991-01-01

A portable air sampling system has been used to assess exposures to various substances while commuting by bicycle in an urban area. The major source of pollutants in this situation is motor vehicle exhaust emissions. Carbon monoxide, measured by electrochemical detection, was found at peak concentrations in excess of 62 ppm, with mean values over 16 individual 35-mm journeys being 10.5 ppm. Respirable suspended particulates, averaged over each journey period, were found at higher concentrations (mean 130 μg m -3 ) than would be expected in indoor situations. Mean exposure to benzene (at 56 μg m -3 ) and other aromatic volatile organic compounds was also relatively high. The influence of wind conditions on exposure was found to be significant. Commuting exposures to carbon monoxide, respirable suspended particulates, and aromatic VOCs were found to be higher than exposures in a busy high street and on common parkland

Effect of coexisting organic substances on radiation resistance of Bacillus pumilus spores suspended in water

International Nuclear Information System (INIS)

Kigawa, Akiko; Tateishi, Tsuneo; Iso, Katsuaki; Kimura, Toshio; Mamuro, Tetsuo

1987-01-01

D values of B. pumilus spores suspended in water have been shown to increase in the presence of some coexisting organic substances. For elucidation of a mechanism or mechanisms involved in such a phenomenon, D-values of B.p. spores were examined by suspending them in aqueous solutions containing various concentrations of ethanol, glycerin, inulin and PVA. All these substances showed abrupt changes in D value at a narrow concentration range of 1 - 10 weight ppm. Solutions containing these substances at their lower limit concentrations and upper limit were prepared, sealed in incubator bottles leaving no air layer and irradiated at 0.7 Mrad with γ-rays. Winkler's method was used for the determination of oxygen concentrations in these solutions. The initial concentration of dissolved oxygen was 8.2 ppm. After irradiation, 3 - 5 ppm of oxygen remained in those solutions containing the lower limit (1 ppm), whereas only less than 0.5 ppm in those containing the upper limits, 2.5 ppm of ethanol, 5 ppm of PVA and 10 ppm each of glycerin and inulin. Therefore, the observed effect of coexisting organic substances on radiation resistance of B. pumilus can be explained by the so-called ''oxygen effect''. (author)

Monitoring the effects of disposal of fine sediments from maintenance dredging on suspended particulate matter concentration in the Belgian nearshore area (southern North Sea)

OpenAIRE

Fettweis, M.; Baeye, M.; Francken, F.; Lauwaert, B.; Van den Eynde, D.; Van Lancker, V.; Martens, C.; Michielsen, T.

2011-01-01

The impact of continuous disposal of fine-grained sediments from maintenance dredging works on the suspended particulate matter concentration in a shallow nearshore turbidity maximum was investigated during dredging experiment (port of Zeebrugge, southern North Sea). Before, during and after the experiment monitoring of SPM concentration using OBS and ADV altimetry was carried out at a location 5 km west of the disposal site. A statistical analysis, based on the concept of populations and sub...

Radionuclide - Soil Organic Matter Interactions

DEFF Research Database (Denmark)

Carlsen, Lars

1985-01-01

Interactions between soil organic matter, i.e. humic and fulvic acids, and radionuclides of primary interest to shallow land burial of low activity solid waste have been reviewed and to some extent studied experimentally. The radionuclides considered in the present study comprise cesium, strontium...

Multi-proxy evidence for compositional change of organic matter in the largest tropical (peninsular) river basin of India

Digital Repository Service at National Institute of Oceanography (India)

Pradhan, U.K.; Ying Wu; Shirodkar, P.V.; Zhang, J.; Zhang, G.

and concentrations of lignin phenols were analyzed in total suspended matter (TSM), sediments, agriculture soils and plants from Godavari basin. The results indicated that the upper tributaries drained heavier carbon (δ13Corg = −20.4 ± 2.2‰) than the lower...

Mobility of the dissolved organic matter through intact boom clay cores

International Nuclear Information System (INIS)

Put, M.J.; Dierckx, A.; Aertsens, M.; Canniere, P. de

1998-01-01

Performance assessment studies are expected to predict the enhancement of the migration of trivalent lanthanides and actinides due to their complexation with organic matter, which play a role as a transport agent [1]. Therefore, the mobility of the dissolved organic matter in the interstitial boom clay water is studied. For the first time, the mobile fraction present in the clay water is concentrated and labelled with a radioisotope to study the mobility of the organic matter in clay and the interaction of the mobile with the non-mobile. The isotopes tested as label are 125 I and 14 C. The 125 I label proved to be unstable and hence discarded. The labelled organic matter is then diluted for migration experiments on boom clay cores under anaerobic conditions. The influence of the molecular size on its mobility is studied by the separation of the labelled organic matter in different size fractions. (orig.)

Elemental analysis of the suspended particulate matter in the air of Tehran using INAA and AAS techniques. Appendix 11

International Nuclear Information System (INIS)

Sohrabpour, M.; Rostami, S.; Athari, M.

1995-01-01

A network of ten sampling stations for monitoring the elemental concentration of the suspended particulate matter (SPM) in the air of Tehran has been established. Instrumental neutron activation analysis (INAA) and atomic absorption spectrometry (AAS) techniques have been used for analysis of the Whatman-41 filters collected during the year 1994. Assessment of the preliminary results using the two techniques has produced the following twenty-one elements: Al, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Fe, K, Mg, Mn, Na, Ni, Pb, Sb, Sc, Ti, V, Zn. Various standard solutions with known concentrations of elements, together with standard reference materials, have been used for quality assurance of the measured concentrations. (author)

Organic matter in uranium concentration during ancient bed oxidation of carboniferons sediments

International Nuclear Information System (INIS)

Kruglova, V.G.; Uspenskij, V.A.; Dement'ev, P.K.; Kochenov, A.V.

1984-01-01

Changes in the organic matter accompanying the process of epigenetic ore formation are studied using the example of a deposit localized in carboniferous molasse strata of the Cretaceous period. Peculiarities of the organic matter as the main mineralization agent are studied by a complex of physical and themical methods. A distinct relationship between the uranium concentration and the degree of organic matter oxigenation is a most characteristic feature of the ore localization, however, there is no direct correlation between the contents of uranium and organic matter in ores. Uranium minerallzation was accumulated during infiltration of acid uraniferous.waters into grey stratum in the process of the bed oxidation zone formation oxidizing. Brown coal matter possessing a maximum adsorbability, as compared to other sedimentary rocks, apprared to be the uranium precipitator. The adsorption was accompanie by the formation of proper uranium minerals (coffinite, pitchblende) due to uranium reduction by oxidizing organic matter. Thus, the oxidative epigenesis was an are-forming process with the uranium concentration on organic matter proportionally to oxidation of the latter

Applicability of FTIR-spectroscopy for characterizing waste organic matter

International Nuclear Information System (INIS)

Smidt, E.

2001-12-01

State and development of waste organic matter were characterized by means of FTIR-spectroscopy. Due to the interaction of infrared light with matter energy is absorbed by chemical functional groups. Chemical preparation steps are not necessary and therefore this method offers a more holistic information about the material. The first part of experiments was focussed on spectra of different waste materials representing various stages of decomposition. Due to characteristics in the fingerprint- region the identity of wastes is provable. Heights of significant bands in the spectrum were measured and relative absorbances were calculated. Changes of relative absorbances indicate the development of organic matter during decomposition. Organic matter of waste samples was compared to organic matter originating from natural analogous processes (peat, soil). The second part of experiments concentrated on a composting process for a period of 260 days. Spectral characteristics of the samples were compared to their chemical, physical and biological data. The change of relative absorbances was reflected by conventional parameters. According to the development of the entire sample humic acids underwent a change as well. For practical use the method offers several possibilities: monitoring of a process, comparison of different processes, quality control of products originating from waste materials and the proof of their identity. (author)

Can particulate organic matter reveal emerging changes in soil organic carbon?

DEFF Research Database (Denmark)

Simonsson, Magnus; Kirchmann, Holger; Magid, Jakob

2014-01-01

different cropping systems, N fertilizer applications, and organic amendments, we found that C and N in the fine to medium sand fraction (0.063-0.600 mm, "Fraction B") showed considerably larger relative errors according to ANOVA (RMSE was 11-20% of the mean), slightly lower values of the F statistic......This study assessed whether particulate organic matter (POM) in sand fractions, isolated by wet sieving after treatment with Na hexametaphosphate, can be a sensitive indicator of incipient changes in the content and composition of soil organic matter. In five long-term field experiments including......, and slightly less contrast between treatments than total organic C and N (RMSE 3-9% of the mean). Imprecision in laboratory procedures only explained part of the increase in RMSE for C and N in Fraction B compared with total C and N; within-field spatial variability most likely had a greater influence...

Trends and the effect of management on macronutrients in fractionated particulate matter in rooster house

Science.gov (United States)

The persistence and long life expectancy of ammonia, odors and toxic pollutants from poultry houses may be due to the ability of suspended particulate matters (SPM) to serve as carriers for odorous compounds such as ammonium ions and volatile organic compounds. SPM is generated from the feed, anima...

Competition for spectral irradiance between epilimnetic optically active dissolved and suspended matter and phytoplankton in the metalimnion. Consequences for limnology and chemistry.

Science.gov (United States)

Bracchini, Luca; Dattilo, Arduino Massimo; Falcucci, Margherita; Hull, Vincent; Tognazzi, Antonio; Rossi, Claudio; Loiselle, Steven Arthur

2011-06-01

In deep lakes, water column stratification isolates the surface water from the deeper bottom layers, creating a three dimensional differentiation of the chemical, physical, biological and optical characteristics of the waters. Chromophoric dissolved organic matter (CDOM) and total suspended solids (TSS) play an important role in the attenuation of ultraviolet and photosynthetically active radiation. In the present analysis of spectral irradiance, we show that the wavelength composition of the metalimnetic visible irradiance was influenced by epilimnetic spatial distribution of CDOM. We found a low occurrence of blue-green photons in the metalimnion where epilimnetic concentrations of CDOM are high. In this field study, the spatial variation of the spectral irradiance in the metalimnion correlates with the observed metalimnetic concentrations of chlorophyll a as well as chlorophyll a : chlorophyll b/c ratios. Dissolved oxygen, pH, and nutrients trends suggest that chlorophyll a concentrations were representative of the phytoplankton biomass and primary production. Thus, metalimnetic changes of spectral irradiance may have a direct impact on primary production and an indirect effect on the spatial trends of pH, dissolved oxygen, and inorganic nutrients in the metalimnion.

Comparison of laser-light diffraction method with other methods of analyzing the particle size distribution in suspensions of latex, pollen, and quartz, and in suspended particulate matter in river water

International Nuclear Information System (INIS)

Heyn, R.D.; Zimmermann, H.U.

1983-01-01

This report gives an idea of different methods being used for the particle size analysis, including a laser light diffraction method and an image analysis method. These comparing measurements have been carried out with suspensions consisting of fresh water and standard particles, ranging between 1 and 100 μm, as well as with suspended particulate matter of the Elbe river. As to standard particles, statistical errors are subject to the width of the size distribution. When using the light diffraction method, the errors vary between 0,7 and 16%, however, when applying the image analysis method, they range between 0,5 and 26%. As a result of the measurements of the suspended particulate matter of the Elbe river, a statistical error of 21% has occured with regard to the image analysis method, whilst the light diffraction method has shown an error of about 4 - 11%. Possible reasons for systematical and random errors have been discussed as to both of these methods. (orig.) [de

Characterization of organic matter in lake sediments from Minnesota and Yellowstone National Park

Science.gov (United States)

Dean, Walter E.

2006-01-01

Samples of sediment from lakes in Minnesota and Yellowstone National Park (YNP) were analyzed for organic carbon (OC), hydrogen richness by Rock-Eval pyrolysis, and stable carbon- and nitrogen-isotope composition of bulk organic matter. Values of delta 13C of lake plankton tend to be around -28 to -32 parts per thousand (0/00). Organic matter with values of delta 13C in the high negative 20s overlap with those of organic matter derived from C3 higher terrestrial plants but are at least 10 0/00 more depleted in 13C than organic matter derived from C4 terrestrial plants. If the organic matter is produced mainly by photosynthetic plankton and is not oxidized in the water column, there may be a negative correlation between H-richness (Rock-Eval pyrolysis H-index) and delta 13C, with more H-rich, algal organic matter having lower values of delta 13C. However, if aquatic organic matter is oxidized in the water column, or if the organic matter is a mixture of terrestrial and aquatic organic matter, then there may be no correlation between H-richness and carbon-isotopic composition. Values of delta 13C lower than about -28 0/00 probably indicate a contribution of bacterial biomass produced in the hypolimnion by chemoautotrophy or methanotrophy. In highly eutrophic lakes in which large amounts of 13C-depleted organic matter is continually removed from the epilimnion by photosynthesis throughout the growing season, the entire carbon reservoir in the epilimnion may become severely 13C-enriched so that 13C-enriched photosynthetic organic matter may overprint 13C-depleted chemosynthetic bacterial organic matter produced in the hypolimnon. Most processes involved with the nitrogen cycle in lakes, such as production of ammonia and nitrate, tend to produce 15N-enriched values of delta 15N. Most Minnesota lake sediments are 15N-enriched. However, some of the more OC-rich sediments have delta 15N values close to zero (delta 15N of air), suggesting that organic matter production is

Biogas production from organic wastes in suspended cell cultures and in biofilms

International Nuclear Information System (INIS)

Simenonov, I.; Chorukova, E.; Mamatarkova, V.; Nikolov, L.

2010-01-01

The results of a comparative study of two biogas production bioprocess systems are presented. The systems submitted to comparison are based on the suspended cells cultures and the biofilm formed on solid inert support. A comprehensive research concept is formulated and discussed. It includes the main considerations regarding the choice of substrate, bioagent as mixed microbial society, type of bioreactors, regimes of functioning, analytical determinations and method of comparison. The main requirements for efficient experimental activity in comparative investigations are formulated. Their satisfaction can grant correctness of the experimental design and data acquisition. On this basis the key parameter of comparison of the two systems is defined as the specific productivity of the bioprocess systems. Under these conditions series of preliminary experiments are carried out for testing the readiness of experimental set ups for long time stable functioning and monitoring devices capabilities to maintain the bioprocess parameters at the determined intervals. These tests grant continuous incessant experimentation with the investigated bioprocess systems. The results obtained show that biofilm bioprocess systems possess up to two and half time higher specific productivity in comparison with the bioprocess systems with the suspended cells. Some visions about the future developments of comparative research on the influence of additional parameters like the mixer rotation steed, organic loads, and higher values of dilution rates are outlined.

Nickel toxicity to benthic organisms: The role of dissolved organic carbon, suspended solids, and route of exposure.

Science.gov (United States)

Custer, Kevin W; Hammerschmidt, Chad R; Burton, G Allen

2016-01-01

Nickel bioavailability is reduced in the presence of dissolved organic carbon (DOC), suspended solids (TSS), and other complexing ligands; however, no studies have examined the relative importance of Ni exposure through different compartments (water, sediment, food). Hyalella azteca and Lymnaea stagnalis were exposed to Ni-amended water, sediment, and food, either separately or in combination. Both organisms experienced survival and growth effects in several Ni compartment tests. The DOC amendments attenuated L. stagnalis Ni effects (survival, growth, and (62)Ni bioaccumulation), and presence of TSS exposures demonstrated both protective and synergistic effects on H. azteca and L. stagnalis. (62)Ni trophic transfer from food to H. azteca and L. stagnalis was negligible; however, bioaccumulating (62)Ni was attributed to (62)Ni-water ((62)Ni flux from food), (62)Ni-TSS, and (62)Ni-food. Overall, H. azteca and L. stagnalis Ni compartment toxicity increased in the following order: Ni-water > Ni-sediment > Ni-all (water, sediment, food) > Ni-food. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Analysis of Septic Tank Performance in Regard to Suspended Solids and Organic Matter Removal

Directory of Open Access Journals (Sweden)

Ala Kirjanova

2011-12-01

Full Text Available Abstract 117 The aim of this work was to evaluate the removal of suspended solids (SS and 7-day biochemical oxygen demand (BOD7 in a three chamber septic tank depending on theoretical wastewater retention time and the degree of septic tank cleanliness. It was found out that the performance of the septic tank depended on the degree of its cleanliness: when the septic tank was clean and retention time was three days, SS and BOS7 removal efficiency was 77±10% and 67±14% respectively, whereas two months later, after septic tank desludging, SS removal efficiency decreased to 53±22% and BOD7 to 32±31%. The performance of the septic tank also depended on theoretical wastewater retention time: when some amount of solids was accumulated at the bottom of the septic tank and wastewater retention time was one day, SS and BOS7 removal efficiency was 45±40% and 33±16% respectively; when retention time was three days, SS removal efficiency increased to 53±22% but BOD7 removal efficiency remained similar to one day retention time, i.e. 32±31%.Article in Lithuanian

Hydrocarbons in the suspended matter and the bottom sediments in different regions of the Black Sea Russian sector

Directory of Open Access Journals (Sweden)

I. A. Nemirovskaya

2017-08-01

Full Text Available Content and composition of hydrocarbons (mainly the aliphatic ones in the suspended matter and the bottom sediments in the Gelendzhik Bay, the Big Sochi water area, the Feodosiya Bay and the Black Sea central part are defined and compared with the total organic carbon and chlorophyll a contents. It is shown that the aliphatic hydrocarbon concentrations exceeding the background ones are found only in the coastal zone. Advancing to the pelagic zone is accompanied by sharp decrease of their concentrations. Petroleum and pyrogenic hydrocarbons are mainly manifested in the polycyclic aromatic hydrocarbons composition. Influence of construction of the Olympic facilities upon distribution of hydrocarbons in the Big Sochi water area was of short duration, and already by 2015 the aliphatic hydrocarbons concentration decreased, on the average, up to 24 µg/l in the surface waters, and up to 18 µg/g – in the bottom sediments. Accumulation of hydrocarbons took place in bottom sediments, where their concentrations exceeded the background ones in terms of dry weight. In the Gelendzhik Bay, their content reached 252 μg/g, and in the composition of organic carbon (Corg > 1 %, which may indicate the contamination of sediments with oil products. In the Feodosiya Bay their part in the composition of Corg did not exceed 0.73 % and was 0.35 % on average. Natural alkanes dominated in the composition of aliphatic hydrocarbons. The bottom sediments are characterized by the predominance of odd high-molecular terrigenous alkanes. The content of polycyclic aromatic hydrocarbons in the studied sediments was rather low: up to 31 ng/g in the Gelendzhik Bay, up to 348 ng/g in the Feodosiya Bay. These concentrations according to the EPA classification are considered background, or minor petroleum hydrocarbons increase the level of aliphatic hydrocarbons in water and sediments, thus creating a modern hydrocarbon background.

Photocatalytic degradation of carbamazepine, clofibric acid and iomeprol with P25 and Hombikat UV100 in the presence of natural organic matter (NOM) and other organic water constituents.

Science.gov (United States)

Doll, Tusnelda E; Frimmel, Fritz H

2005-01-01

The photocatalytic degradation of natural organic matter (NOM) and organic substance mixtures under simulated solar UV light has been investigated with suspended TiO(2). It could be shown by size-exclusion chromatography that photocatalysis of NOM led to a reduction of the average hydrodynamic radii and presumably of the nominal molecular weight, too. The decrease of the UV/Vis absorption of NOM was faster than the NOM mineralization. This study also focuses on the different abilities of photocatalytic materials (P25 and Hombikat UV100) to decrease persistent substances influenced by the presence of NOM and mixtures of pharmaceuticals or diagnostic agents. In general, the presence of NOM and other organic substances retarded the photocatalysis of a specific persistent substance by the combination of radiation attenuation, competition for active sites and surface deactivation of the catalyst by adsorption. The results of this work prove that photocatalysis is a promising technology to reduce persistent substances like NOM, carbamazepine, clofibric acid, iomeprol and iopromide even if they are present in a complex matrix.

Chemical examination of the organic matter in oil shales

Energy Technology Data Exchange (ETDEWEB)

Robertson, J B

1914-01-01

The analyses of Broxburn (Scotland), Pumpherston (Scotland), Armadale (Scotland), Australian, and Knightsbridge oil shales were given. Also, the action of nitric acid and solvents on some of the oil shales was determined. Carbon-hydrogen ratios of the oil shales varied from 6 to more than 8, and the shales with the lowest ratio (most hydrogen per carbon) produced the largest amount of oil from a given amount of organic matter. There was little resinous material in the oil shales, and most of the organic matter was insoluble in organic solvents. Nitric acid oxidized Australian torbanite, Broxburn shale, New Battle cannel coal (Scotland), and Glenfullock peat to organic acids. The hydrogen content of the organic acids obtained by oxidizing the following materials increased from ordinary coal to cannel coal to peat to Broxburn shale to torbanite. The organic substance in oil shale is a decomposition product of vegetable matter similar to that found in peat and cannel coal, and it was produced by a definite combination of external conditions.

Quantifying the degradation of organic matter in marine sediments: A review and synthesis

Science.gov (United States)

Arndt, Sandra; Jørgensen, B. B.; LaRowe, D. E.; Middelburg, J. J.; Pancost, R. D.; Regnier, P.

2013-08-01

Quantifying the rates of biogeochemical processes in marine sediments is essential for understanding global element cycles and climate change. Because organic matter degradation is the engine behind benthic dynamics, deciphering the impact that various forces have on this process is central to determining the evolution of the Earth system. Therefore, recent developments in the quantitative modeling of organic matter degradation in marine sediments are critically reviewed. The first part of the review synthesizes the main chemical, biological and physical factors that control organic matter degradation in sediments while the second part provides a general review of the mathematical formulations used to model these processes and the third part evaluates their application over different spatial and temporal scales. Key transport mechanisms in sedimentary environments are summarized and the mathematical formulation of the organic matter degradation rate law is described in detail. The roles of enzyme kinetics, bioenergetics, temperature and biomass growth in particular are highlighted. Alternative model approaches that quantify the degradation rate constant are also critically compared. In the third part of the review, the capability of different model approaches to extrapolate organic matter degradation rates over a broad range of temporal and spatial scales is assessed. In addition, the structure, functions and parameterization of more than 250 published models of organic matter degradation in marine sediments are analyzed. The large range of published model parameters illustrates the complex nature of organic matter dynamics, and, thus, the limited transferability of these parameters from one site to another. Compiled model parameters do not reveal a statistically significant correlation with single environmental characteristics such as water depth, deposition rate or organic matter flux. The lack of a generic framework that allows for model parameters to be

Effect of organic fertilizers derived dissolved organic matter on pesticide sorption and leaching

Energy Technology Data Exchange (ETDEWEB)

Li Kun [Department of Plant, Soil, and Insect Sciences, Stockbridge Hall, University of Massachusetts, Amherst, MA 01003 (United States); Xing Baoshan [Department of Plant, Soil, and Insect Sciences, Stockbridge Hall, University of Massachusetts, Amherst, MA 01003 (United States) and Northeast Institute of Geography and Agro-ecology, CAS, Harbin 150040 (China)]. E-mail: bx@pssci.umass.edu; Torello, William A. [Department of Plant, Soil, and Insect Sciences, Stockbridge Hall, University of Massachusetts, Amherst, MA 01003 (United States)

2005-03-01

Incorporation of organic fertilizers/amendments has been, and continues to be, a popular strategy for golf course turfgrass management. Dissolved organic matter (DOM) derived from these organic materials may, however, facilitate organic chemical movement through soils. A batch equilibrium technique was used to evaluate the effects of organic fertilizer-derived DOM on sorption of three organic chemicals (2,4-D, naphthalene and chlorpyrifos) in USGA (United States Golf Association) sand, a mixed soil (70% USGA sand and 30% native soil) and a silt loam soil (Typic Fragiochrept). DOM was extracted from two commercial organic fertilizers. Column leaching experiments were also performed using USGA sand. Sorption experiments showed that sorption capacity was significantly reduced with increasing DOM concentration in solution for all three chemicals. Column experimental results were consistent with batch equilibrium data. These results suggest that organic fertilizer-derived DOM might lead to enhanced transport of applied chemicals in turf soils. - Dissolved organic matter could result in enhanced transport of chemicals applied to turf.

Effect of organic fertilizers derived dissolved organic matter on pesticide sorption and leaching

International Nuclear Information System (INIS)

Li Kun; Xing Baoshan; Torello, William A.

2005-01-01

Incorporation of organic fertilizers/amendments has been, and continues to be, a popular strategy for golf course turfgrass management. Dissolved organic matter (DOM) derived from these organic materials may, however, facilitate organic chemical movement through soils. A batch equilibrium technique was used to evaluate the effects of organic fertilizer-derived DOM on sorption of three organic chemicals (2,4-D, naphthalene and chlorpyrifos) in USGA (United States Golf Association) sand, a mixed soil (70% USGA sand and 30% native soil) and a silt loam soil (Typic Fragiochrept). DOM was extracted from two commercial organic fertilizers. Column leaching experiments were also performed using USGA sand. Sorption experiments showed that sorption capacity was significantly reduced with increasing DOM concentration in solution for all three chemicals. Column experimental results were consistent with batch equilibrium data. These results suggest that organic fertilizer-derived DOM might lead to enhanced transport of applied chemicals in turf soils. - Dissolved organic matter could result in enhanced transport of chemicals applied to turf

Optimization and development of analytical methods for the determination of new brominated flame retardants and polybrominated diphenyl ethers in sediments and suspended particulate matter

Energy Technology Data Exchange (ETDEWEB)

Lopez, P. [VU University Amsterdam, Institute for Environmental Studies (IVM), Amsterdam (Netherlands); Institute for Reference Materials and Measurements, European Commission, Joint Research Centre, Retieseweg 111, 2440, Geel (Belgium); Brandsma, S.A.; Leonards, P.E.G.; Boer, J. de [VU University Amsterdam, Institute for Environmental Studies (IVM), Amsterdam (Netherlands)

2011-05-15

With more stringent legislation on brominated flame retardants, it is expected that increasing amounts of substitutes would replace polybrominated diphenylethers (PBDEs). Therefore, the development and optimization of analytical methodologies that allow their identification and quantification are of paramount relevance. This work describes the optimization of an analytical procedure to determine pentabromochlorocyclohexane, tetrabromo-o-chlorotoluene, 2,3,5,6-tetrabromo-p-xylene, tetrabromophthalic anhydride, 2,3,4,5,6-pentabromotoluene, tris(2,3-dibromopropyl)phosphate, decabromodiphenylethane and 1,2-bis(2,4,6-tribromophenoxy)ethane together with PBDEs in sediments and in suspended particulate matter. This method comprises a pressurized liquid extraction followed by three cleanup steps (gel permeation chromatography and solid phase extraction on Oasis trademark HLB and on silica cartridges). Gas chromatography-mass spectrometry, using electron capture negative chemical ionization, is used for the final analysis. The proposed method provides recoveries >85%. The method was applied to sediment and suspended particulate matter samples from different locations in the Western Scheldt estuary (the Netherlands). To the best of our knowledge, this is the first time that the occurrence of the additive flame retardants 2,3,5,6-tetrabromo-p-xylene, 3,4,5,6-tetrabromo-o-chlorotoluene and 2,3,4,5,6-pentabromochlorocyclohexane is reported in the literature. The concentrations of these new flame retardants ranged from 0.05 to 0.30 {mu}g/kg dry weight. (orig.)

Spectral band selection for classification of soil organic matter content

Science.gov (United States)

Henderson, Tracey L.; Szilagyi, Andrea; Baumgardner, Marion F.; Chen, Chih-Chien Thomas; Landgrebe, David A.

1989-01-01

This paper describes the spectral-band-selection (SBS) algorithm of Chen and Landgrebe (1987, 1988, and 1989) and uses the algorithm to classify the organic matter content in the earth's surface soil. The effectiveness of the algorithm was evaluated comparing the results of classification of the soil organic matter using SBS bands with those obtained using Landsat MSS bands and TM bands, showing that the algorithm was successful in finding important spectral bands for classification of organic matter content. Using the calculated bands, the probabilities of correct classification for climate-stratified data were found to range from 0.910 to 0.980.

Accumulation of {sup 241}Am by suspended matter, diatoms and aquatic weeds of the Yenisei River

Energy Technology Data Exchange (ETDEWEB)

Zotina, T.A., E-mail: t_zotina@ibp.r [Institute of Biophysics SB RAS, Akademgorodok, Krasnoyarsk 660036 (Russian Federation); Bolsunovsky, A.Ya.; Bondareva, L.G. [Institute of Biophysics SB RAS, Akademgorodok, Krasnoyarsk 660036 (Russian Federation)

2010-02-15

In this work we experimentally estimated the capacities of the key components of the Yenisei River (Russia): particulate suspended matter (seston), diatom microalgae, and submerged macrophytes for accumulating {sup 241}Am from water. In our experiments large particles of seston (>8 mum), comparable in size with diatoms, took up most of americium from water. The accumulation of americium by isolated diatom algae (Asterionella formosa and Diatoma vulgare) was lower than by total seston. The concentration factors (CFs) of {sup 241}Am for seston of the Yenisei River in our experiments were (2.8-6.9).10{sup 5}; for diatoms - (1.5-4.2).10{sup 4}. The CFs for aquatic plant Elodea canadensis were within the same order of magnitude as those for diatoms. Activity concentration and CFs of {sup 241}Am were nearly the same in experiments under dark and light conditions. This is indicative of an energy independent mechanism of americium uptake from the water by diatoms and submerged macrophytes.

Particulate Matter Resuspension in Mississippi Bight Evaluated with CONCORDE's Synthesis Model

Science.gov (United States)

O'Brien, S. J.; Quas, L. M.; Miles, T. N.; Pan, C.; Cambazoglu, M. K.; Soto Ramos, I. M.; Greer, A. T.; Church, I.; Wiggert, J. D.

2017-12-01

The CONsortium for oil spill exposure pathways in COastal River-Dominated Ecosystems (CONCORDE) was established to investigate the complex fine-scale biological, chemical and physical interactions in a marine system controlled by pulsed-river plume dynamics. During CONCORDE's spring 2016 field campaign, the In Situ Ichthyoplankton Imaging System (ISIIS) on the R/V Point Sur and the Scanfish on the R/V Pelican comprehensively characterized the physical and biological structure in the region. Increased suspended particulate matter was observed by the ISIIS, with concentrations at depth sufficient to completely occlude the in situ images of planktonic organisms. Data was also collected on the continental shelf during the spring cruise by the RU31 glider in the proximity of the Mississippi River Delta, east of the ISIIS / Scanfish transects. Backscatter and salinity observed by the Scanfish and glider showed elevated suspended particulate matter and increased salinity, suggesting a linkage to shoreward advection from the continental shelf of oceanic waters that are sufficiently energetic to drive sediment resuspension. As part of the CONCORDE research effort, a four-dimensional biogeochemical/lower trophic level synthesis model for Mississippi Sound and Bight has been developed, based on the Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) Modeling System. This study utilizes CONCORDE's synthesis model to investigate the physical forcing mechanisms affecting the increased suspended particulate matter concentration observed in the Mississippi Bight during spring 2016, and advection pathways between estuarine and shelf waters in the northern Gulf of Mexico. The results show that episodic, advection-driven resuspension is a critical aspect controlling suspended sediment distributions in Mississippi Bight, which has implications for observed spatio-temporal patterns of planktonic species.

Is old organic matter simple organic matter?

Science.gov (United States)

Nunan, Naoise; Lerch, Thomas; Pouteau, Valérie; Mora, Philippe; Changey, Fréderique; Kätterer, Thomas; Herrmann, Anke

2016-04-01

Bare fallow soils that have been deprived of fresh carbon inputs for prolonged periods contain mostly old, stable organic carbon. In order to shed light on the nature of this carbon, the functional diversity profiles (MicroResp™, Biolog™ and enzyme activity spectra) of the microbial communities of long-term barefallow soils were analysed and compared with those of the microbial communities from their cultivated counterparts. The study was based on the idea that microbial communities adapt to their environment and that therefore the catabolic and enzymatic profiles would reflect the type of substrates available to the microbial communities. The catabolic profiles suggested that the microbial communities in the long-term bare-fallow soil were exposed to a less diverse range of substrates and that these substrates tended to be of simpler molecular forms. Both the catabolic and enzyme activity profiles suggested that the microbial communities from the long-term bare-fallow soils were less adapted to using polymers. These results do not fit with the traditional view of old, stable carbon being composed of complex, recalcitrant polymers. An energetics analysis of the substrate use of the microbial communities for the different soils suggested that the microbial communities from the long-term bare-fallow soils were better adapted to using readily oxidizable,although energetically less rewarding, substrates. Microbial communities appear to adapt to the deprivation of fresh organic matter by using substrates that require little investment.

Determination of organic-matter content of Appalachian Devonian shales from gamma-ray logs

International Nuclear Information System (INIS)

Schmoker, J.W.

1981-01-01

The organic-matter content of the Devonian shale of the Appalachian basin is important for assessing the natural-gas resources of these rocks, and patterns of organic-matter distribution convey information on sedimentary processes and depositional environment. In most of the western part of the Appalachian basin the organic-matter content of the Devonian shale can be estimated from gamma-ray wire-line logs using the equation: phi 0 = (γ/sub B/ - γ)/1.378A, where phi 0 is the organic-matter content of the shale (fractional volume), γ the gamma-ray intensity (API units), γ/sub B/ the gamma-ray intensity if no organic matter is present (API units), and A the slope of the crossplot of gamma-ray intensity and formation density (API units/(g/cm 3 )). Organic-matter contents estimated using this equation are compared with organic-matter contents determined from direct laboratory analyses of organic carbon for 74 intervals of varying thickness from 12 widely separated wells. The organic-matter content of these intervals ranges from near zero to about 20% by volume. The gamma-ray intensity of the Cleveland Member of the Ohio Shale and the lower part of the Olentangy Shale is anomalously low compared to other Devonian shales of similar richness, so that organic-matter content computed for each of these units from gamma-ray logs is likely to be too low. Wire-line methods for estimating organic-matter content have the advantages of economy, readily available sources of data, and continuous sampling of the vertically heterogenous shale section. The gamma-ray log, in particular, is commonly run in the Devonian shale, its response characteristics are well known, and the cumulative pool of gamma-ray logs forms a large and geographically broad data base. The quantitative computation of organic-matter content from gamma-ray logs should be of practical value in studies of the Appalachian Devonian shale. 16 figures

Effect of phosphorus and organic matter on zinc availability on rice

International Nuclear Information System (INIS)

Gupta, G.N.; Kamath, M.B.; Motsara, M.R.

1977-01-01

Pot culture experiment was conducted on grey brown podzolic soil (Palampur) and Tarai soil (Pantnagar) to study the influence of the addition of organic matter, phosphorus and zinc on the uptake and utilization of zinc by rice crop. In podzolic soils the combined application of Zn-P and Zn-organic matter resulted in reduced zinc content in crop but the crop yield was not affected. The uptake and utilization of applied zinc increased with P application. In Tarai soil, crop response to Zn, P and organic matter was obtained when applied separately. A negative zinc x P and zinc x organic matter interaction was obtained on yield. However, zinc content of the crop increased due to the application of P, organic matter and zinc. The uptake and utilization of applied zinc increased with P application. The analysis of soils after crop harvest indicated an increased amount of 0.1 N HCl extractable zinc in soils treated with zinc in Tarai soils while in podzolic soil from Palampur, the available zinc increased only under the combined application of zinc and P. (author)

Response of organic matter quality in permafrost soils to warming

Science.gov (United States)

Plaza, C.; Pegoraro, E.; Schuur, E.

2016-12-01

Global warming is predicted to thaw large quantities of the perennially frozen organic matter stored in northern permafrost soils. Upon thaw, this organic matter will be exposed to lateral export to water bodies and to microbial decomposition, which may exacerbate climate change by releasing significant amounts of greenhouse gases. To gain an insight into these processes, we investigated how the quality of permafrost soil organic matter responded to five years of warming. In particular, we sampled control and experimentally warmed soils in 2009 and 2013 from an experiment established in 2008 in a moist acidic tundra ecosystem in Healy, Alaska. We examined surface organic (0 to 15 cm), deep organic (15 to 35 cm), and mineral soil layers (35 to 55 cm) separately by means of stable isotope analysis (δ13C and δ15N) and solid-state 13C nuclear magnetic resonance. Compared to the control, the experimental warming did not affect the isotopic and molecular composition of soil organic matter across the depth profile. However, we did find significant changes with time. In particular, in the surface organic layer, δ13C decreased and alkyl/O-alkyl ratio increased from 2009 to 2013, which indicated variations in soil organic sources (e.g., changes in vegetation) and accelerated decomposition. In the deep organic layer, we found a slight increase in δ15N with time. In the mineral layer, δ13C values decreased slightly, whereas alkyl C/O-alkyl ratio increased, suggesting a preferential loss of relatively more degraded organic matter fractions probably by lateral transport by water flowing through the soil. Acknowledgements: This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No. 654132. Web site: http://vulcan.comule.com

Can Biochar Protect Labile Organic Matter Against Mineralization in Soil?

Institute of Scientific and Technical Information of China (English)

Giovanna B.MELAS; Oriol ORTIZ; Josep M.ALACA(N)IZ

2017-01-01

Biochar could help to stabilize soil organic (SOM) matter,thus sequestering carbon (C) into the soil.The aim of this work was to determine an easy method i) to estimate the effects of the addition of biochar and nutrients on the organic matter (SOM)mineralization in an artificial soil,proposed by the Organization for Economic Co-operation and Development (OECD),amended with glucose and ii) to measure the amount of labile organic matter (glucose) that can be sorbed and thus be partially protected in the same soil,amended or not amended with biochar.A factorial experiment was designed to check the effects of three single factors (biochar,nutrients,and glucose) and their interactions on whole SOM mineralization.Soil samples were inoculated with a microbial inoculum and preincubated to ensure that their biological activities were not limited by a small amount of microbial biomass,and then they were incubated in the dark at 21 ℃ for 619 d.Periodical measurements of C mineralized to carbon dioxide (CO2) were carried out throughout the 619-d incubation to allow the mineralization of both active and slow organic matter pools.The amount of sorbed glucose was calculated as the difference between the total and remaining amounts of glucose added in a soil extract.Two different models,the Freundlich and Langmuir models,were selected to assess the equilibrium isotherms of glucose sorption.The CO2-C release strongly depended on the presence of nutrients only when no biochar was added to the soil.The mineralization of organic matter in the soil amended with both biochar and glucose was equal to the sum of the mineralization of the two C sources separately.Furthermore,a significant amount of glucose can be sorbed on the biochar-amended soil,suggesting the involvement of physico-chemical mechanisms in labile organic matter protection.

Neutron activation analysis determination of trace elements in suspended particulate material and in central Thyrrenian sea sediments

International Nuclear Information System (INIS)

Madaro, M.; Moauro, R.; Boniforti, R.

1985-01-01

Neutron activation analysis and gamma-spectrometry have been applied to the instrumental determination of 26 elements (As, Au, Ca, Ce, Co, Cr, Cs, Eu, Fe, Hf, Hg, La, Lu, Mn, Rb, Sb, Sc, Se, Sm, Ta, Tb, Th, W, Yb, Zn, Zr) in samples of suspended particulate matter and sediments collected in the stretch of Tyrrhenian Sea between the Volturno River mouth and the Cape of Circeo. Some of these elements have particular importance because they can be toxic to the organisms or can be used as tracers in the aquatic environment of radioisotopes generated in activation or fission processes. Results show that some elements, not constituting particular crystal lattices, are more concentrated in particulate matter than in sediments. Such results agree with the hypothesis, supported also by others, that particulate matter acts as a scavenger with respect to most microelements, because of both biological and physico-chemical phenomena

Heterogeneity of the organic matter in the Guayuta group, Eastern Venezuelan Basin

Energy Technology Data Exchange (ETDEWEB)

Alberdi, M.; Gallango, O.; Ruggiero, A.; Jordan, N. (Intevep, S.A., Caracas (Venezuela)); Lefargue, E. (I.F.P., Rueil Malmaison (France))

1993-02-01

The purpose of this study is to evaluate the organic matter heterogeneities in the Guayuta Group as a principal hydrocarbon source rock in the Eastern Venezuelan Basin. In order to do this, thirteen wells and five work stations on outcrops of the Interior Mountain Belt were analyzed to study the regional and vertical variations in the geochemical characteristics of the organic matter. It is possible to detect significant differences in quality and quantity of the organic matter which could corroborate the regional development of two organic facies from North to South in the Maturin Subbasin. The northern organic facies show excellent characteristics as source rock. The study of vertical distribution of organic matter was carried out in a well of northern part of the Monagas state, which represents the southern organic facies. It shows an irregular input of continental organic matter, thermally immature. Besides the organic matter content was low (around 1.5%) without depth tendencies. These sediments are clastic and bioclastic in contrast with carbonates and pelagic shales of the Guayuta Group in the Interior Mountain Belt. The outcrop samples studied show a high total organic content (2-6%) despite the high maturity determined on kerogen. The systematic study of this geochemical parameter show pseudocyclic relationships with a general tendency to increase toward the bottom of the section. V, Ni, and S determinations could indicate that anoxic conditions were developing toward the North where the marine organic matter was sedimenting. The results of this study are in agreement with paleogeographic model of sedimentation during middle and late Cretaceous, with sources of sediments from South and a progressive depth of the basin toward the North.

Application of digital image processing to a β-gauge for determining mass concentration of suspending particulate matter in atmosphere

International Nuclear Information System (INIS)

Gotoh, Takao

1992-01-01

A two-dimensional image of the mass concentration of suspending particulate matter (SPM) collected on Millipore filter paper was photographed with Ultrofilm- 3 H. The printed paper image was transformed into a digital image (256 x 256 pixels) with 256 gray levels. Two results were obtained. The averaged values of gray level over all pixels of the digital image was found to correlate with the mass value measured by a β-gauge. The characteristic range of the digital image which was transformed to frequency by two-dimensional fast fourier transformation was found in the low frequency. It was presumed to relate to SPM from anthropogenic sources because the SPMs usually show higher density and smaller particle size than SPMs from natural sources. (author)

Controlled experimental soil organic matter modification for study of organic pollutant interactions in soil

International Nuclear Information System (INIS)

Ahmed, Ashour A.; Kühn, Oliver; Leinweber, Peter

2012-01-01

Interactions of organic pollutants with soil organic matter can be studied by adsorption of the pollutants on well-characterized soil samples with constant mineralogy but different organic matter compositions. Therefore, the objectives of the current study are establishing a set of different, well-characterized soil samples by systematic modifications of their organic matter content and molecular composition and prove these modifications by advanced complementary analytical techniques. Modifications were done by off-line pyrolysis and removal/addition of hot-water extracted organic fraction (HWE) from/to the original soil sample. Both pyrolysis-field ionization mass spectrometry (Py-FIMS) and synchrotron-based C- and N- X-ray absorption near-edge structure spectroscopy (XANES) were applied to investigate the composition of the soil organic matter. These complementary analytical methods in addition to elemental analysis agreed in showing the following order of organic matter contents: pyrolyzed soil < soil residue < original soil < soil + 3 HWE < soil + 6 HWE < HWE. The addition of HWE to the soil sample increases the relative proportions of carbohydrates, N-containing heterocyclic compounds and peptides, and decreases the relative proportions of phenols, lignin monomers and dimers, and lipids. The most abundant organic compound classes in the pyrolyzed sample are aromatics, aliphatic nitriles, aldehydes, five- and six-membered N-containing heterocyclic compounds, and aliphatic carboxylic acids. It can be expected that removal or addition of HWE, that mimic biomass inputs to soil or soil amendments, change the binding capacity for organic pollutants less intensively than heat impact, e.g. from vegetation burning. It will be possible to interpret kinetic data on the pollutants adsorption by these original and modified soil samples on the basis of the bond- and element-specific speciation data through C-XANES and N-XANES and the molecular-level characterization

Continuous-flow centrifugation to collect suspended sediment for chemical analysis

Science.gov (United States)

Conn, Kathleen E.; Dinicola, Richard S.; Black, Robert W.; Cox, Stephen E.; Sheibley, Richard W.; Foreman, James R.; Senter, Craig A.; Peterson, Norman T.

2016-12-22

Recent advances in suspended-sediment monitoring tools and surrogate technologies have greatly improved the ability to quantify suspended-sediment concentrations and to estimate daily, seasonal, and annual suspended-sediment fluxes from rivers to coastal waters. However, little is known about the chemical composition of suspended sediment, and how it may vary spatially between water bodies and temporally within a single system owing to climate, seasonality, land use, and other natural and anthropogenic drivers. Many water-quality contaminants, such as organic and inorganic chemicals, nutrients, and pathogens, preferentially partition in sediment rather than water. Suspended sediment-bound chemical concentrations may be undetected during analysis of unfiltered water samples, owing to small water sample volumes and analytical limitations. Quantification of suspended sediment‑bound chemical concentrations is needed to improve estimates of total chemical concentrations, chemical fluxes, and exposure levels of aquatic organisms and humans in receiving environments. Despite these needs, few studies or monitoring programs measure the chemical composition of suspended sediment, largely owing to the difficulty in consistently obtaining samples of sufficient quality and quantity for laboratory analysis.A field protocol is described here utilizing continuous‑flow centrifugation for the collection of suspended sediment for chemical analysis. The centrifuge used for development of this method is small, lightweight, and portable for the field applications described in this protocol. Project scoping considerations, deployment of equipment and system layout options, and results from various field and laboratory quality control experiments are described. The testing confirmed the applicability of the protocol for the determination of many inorganic and organic chemicals sorbed on suspended sediment, including metals, pesticides, polycyclic aromatic hydrocarbons, and

Insights in groundwater organic matter from Liquid Chromatography-Organic Carbon Detection

Science.gov (United States)

Rutlidge, H.; Oudone, P.; McDonough, L.; Andersen, M. S.; Baker, A.; Meredith, K.; O'Carroll, D. M.

2017-12-01

Understanding the processes that control the concentration and characteristics of organic matter in groundwater has important implications for the terrestrial global carbon budget. Liquid Chromatography - Organic Carbon Detection (LC-OCD) is a size-exclusion based chromatography technique that separates the organic carbon into molecular weight size fractions of biopolymers, humic substances, building blocks (degradation products of humic substances), low molecular weight acids and low molecular weight neutrals. Groundwater and surface water samples were collected from a range of locations in Australia representing different surface soil, land cover, recharge type and hydrological properties. At one site hyporheic zone samples were also collected from beneath a stream. The results showed a general decrease in the aromaticity and molecular weight indices going from surface water, hyporheic downwelling and groundwater samples. The aquifer substrate also affected the organic composition. For example, groundwater samples collected from a zone of fractured rock showed a relative decrease in the proportion of humic substances, suggestive of sorption or degradation of humic substances. This work demonstrates the potential for using LC-OCD in elucidating the processes that control the concentration and characteristics of organic matter in groundwater.

Age heterogeneity of soil organic matter

International Nuclear Information System (INIS)

Rethemeyer, J.; Grootes, P.M.; Bruhn, F.; Andersen, N.; Nadeau, M.J.; Kramer, C.; Gleixner, G.

2004-01-01

Accelerator mass spectrometry (AMS) radiocarbon measurements were used to investigate the heterogeneity of organic matter in soils of agricultural long-term trial sites in Germany and Great Britain. The strong age heterogeneity of the soil organic matter (SOM) is reflected by highly variable 14 C values of different organic components, ranging from modern (>100 pMC) to 7% modern carbon (pMC). At the field experiment in Halle (Germany), located in a heavily industrialized area, an increase of 14 C content with increasing depth was observed even though the input of modern plant debris should be highest in the topsoil. This is attributed to a significant contribution of old carbon (of up to 50% in the topsoil) to SOM. As a test to exclude the old carbon contamination, more specific SOM fractions were extracted. However, even a phospholipid fraction representing viable microbial biomass that is supposed to be short-lived in SOM, shows a strong influence of old, refractory carbon, when radiocarbon dated. In contrast, 14 C data of other field trials distant from industrial areas indicate that there inputs of old carbon to the soil are lower or even absent. Such locations are more favorable to study SOM stabilization and to quantify turnover of organic carbon in soils

Multivariate analysis of the influences of oceanic and meteorological processes on suspended particulate matter distributions in Mississippi coastal waters

Science.gov (United States)

O'Brien, S. J.; Fitzpatrick, P. J.; Dzwonkowski, B.; Dykstra, S. L.; Wallace, D. J.; Church, I.; Wiggert, J. D.

2016-02-01

The Mississippi Sound is influenced by a high volume of sediment discharge from the Biloxi River, Mobile Bay via Pas aux Herons, Pascagoula River, Pearl River, Wolf River, and Lake Pontchartrain through the Rigolets. The river discharge, variable wind speed, wind direction and tides have a significant impact on the turbidity and transport of sediments in the Sound. Level 1 Moderate Resolution Imaging Spectroradiometer (MODIS) data is processed to extract the remote sensing reflectance at the wavelength of 645 nm and binned into an 8-day composite at a resolution of 500 m. The study uses a regional ocean color algorithm to compute suspended particulate matter (SPM) concentration based on these 8-day composite images. Multivariate analysis is applied between the SPM and time series of tides, wind, turbidity and river discharge measured at federal and academic institutions' stations and moorings. The multivariate analysis also includes in situ measurements of suspended sediment concentration and advective exchanges through the Mississippi Sound's tidal inlets between the coastal shelf and the nearshore estuarine waters. Mechanisms underlying the observed spatiotemporal distribution of SPM, including material exchange between the Sound and adjacent shelf waters, will be explored. The results of this study will contribute to current understanding of exchange mechanisms and pathways with the Mississippi Bight via the Mississippi Sound's tidal inlets.

Enhancing organic matter removal, biopolymer recovery and electricity generation from distillery wastewater by combining fungal fermentation and microbial fuel cell.

Science.gov (United States)

Ghosh Ray, S; Ghangrekar, M M

2015-01-01

For enhancing organic matter removal from cereal-based distillery stillage two-stage treatment consisting of fermentation by Aspergillus awamori followed by microbial fuel cell (MFC) is proposed. Considerable reduction in total and soluble chemical oxygen demand (COD) up to 70% and 40%, respectively, along with 98% reduction of suspended solids (SS) has been achieved during fungal pretreatment. The process generated chitosan, a useful fermentation byproduct from fungal mycelia, as 0.6-0.7g/l of settled sludge with mycelium (3.8% solids). Prior treatment of wastewater with fungal strain enhanced the power generation in MFC by 2.9 times at an organic loading rate of 1.5kgCOD/m(3)day, demonstrating soluble COD reduction of 92% in MFC. While treating distillery wastewater, this two-stage integrated biological process demonstrated overall 99% COD removal and almost complete removal of SS, delivering ample scope for scale-up and industrial application to offer effective solution for distillery wastewater treatment. Copyright © 2014 Elsevier Ltd. All rights reserved.

Insights into the nature of cometary organic matter from terrestrial analogues

Science.gov (United States)

Court, Richard W.; Sephton, Mark A.

2012-04-01

The nature of cometary organic matter is of great interest to investigations involving the formation and distribution of organic matter relevant to the origin of life. We have used pyrolysis-Fourier transform infrared (FTIR) spectroscopy to investigate the chemical effects of the irradiation of naturally occurring bitumens, and to relate their products of pyrolysis to their parent assemblages. The information acquired has then been applied to the complex organic matter present in cometary nuclei and comae. Amalgamating the FTIR data presented here with data from published studies enables the inference of other comprehensive trends within hydrocarbon mixtures as they are progressively irradiated in a cometary environment, namely the polymerization of lower molecular weight compounds; an increased abundance of polycyclic aromatic hydrocarbon structures; enrichment in 13C; reduction in atomic H/C ratio; elevation of atomic O/C ratio and increase in the temperature required for thermal degradation. The dark carbonaceous surface of a cometary nucleus will display extreme levels of these features, relative to the nucleus interior, while material in the coma will reflect the degree of irradiation experienced by its source location in the nucleus. Cometary comae with high methane/water ratios indicate a nucleus enriched in methane, favouring the formation of complex organic matter via radiation-induced polymerization of simple precursors. In contrast, production of complex organic matter is hindered in a nucleus possessing a low methane/water ration, with the complex organic matter that does form possessing more oxygen-containing species, such as alcohol, carbonyl and carboxylic acid functional groups, resulting from reactions with hydroxyl radicals formed by the radiolysis of the more abundant water. These insights into the properties of complex cometary organic matter should be of particular interest to both remote observation and space missions involving in situ

Monitoring of suspended particulate matter (SPM), heavy metals and other parameters in some workplaces

International Nuclear Information System (INIS)

Kinyua, A.M.; Gatebe, C.K.; Mangala, M.J.; Korir, A.K.; Bartilol, S.; Maina, D.M.; Mugera, W.G.; Kamau, G.N.; Chakaya, J.M.; Karama, M.; Miungu, D.M.; Kitio, V.

2000-01-01

This report presents results of measurements of sound levels, chemical analysis of air particulate matter and soil samples from two factories in Nairobi. A preliminary assessment of suspended particulate matter (SPM) in a residential site and its possible impacts on acute respiratory infections (ARI) of children under five years of age is also reported. Our investigations show that for Factory A, the Soil pH measurements within the Factory were more basic (pH=8.5) than those collected near a complainant's residence (pH=7.2). The sound level measurements showed that the maximum noise level recorded was 90 dB. This was at a distance of about 0.5 m from the main exhaust vent of the Factory (20 m above ground level). There was a strong ''detergent-perfume'' odour within and outside the Factory premises especially towards the complainant's side. However, the odour fluctuated. There was also no smoke emissions noticed during the site visits when the factory was operational. For Factory B, the major source of environmental degradation was drainage and management of the factory effluents. The BOD and COD levels for effluents samples analyzed ( 3 whereas the fine particles ranged from 16.2-24.4 μm/m 3 . The prevalence of ARI cases in 1998 ranged between 29.9% in January to the highest level of 59.6% in June. The total number of children who presented themselves throughout the study period, January-December 1998, was 146. A parallel study of dust sampling was also carried out from January to December 1998 in a typical office environment. Dust levels recorded from the working office environment at the Institute of Nuclear Science was found to range from 0. 44 -1.79 μg/cm 2 /day. (author)

Ultraclean individual suspended single-walled carbon nanotube field effect transistor

Science.gov (United States)

Liu, Siyu; Zhang, Jian; Nshimiyimana, Jean Pierre; Chi, Xiannian; Hu, Xiao; Wu, Pei; Liu, Jia; Wang, Gongtang; Sun, Lianfeng

2018-04-01

In this work, we report an effective technique of fabricating ultraclean individual suspended single-walled carbon nanotube (SWNT) transistors. The surface tension of molten silver is utilized to suspend an individual SWNT between a pair of Pd electrodes during annealing treatment. This approach avoids the usage and the residues of organic resist attached to SWNTs, resulting ultraclean SWNT devices. And the resistance per micrometer of suspended SWNTs is found to be smaller than that of non-suspended SWNTs, indicating the effect of the substrate on the electrical properties of SWNTs. The ON-state resistance (˜50 kΩ), mobility of 8600 cm2 V-1 s-1 and large on/off ratio (˜105) of semiconducting suspended SWNT devices indicate its advantages and potential applications.

Intra-annual variability of carbon and nitrogen stable isotopes in suspended organic matter in waters of the western continental shelf of India

Digital Repository Service at National Institute of Oceanography (India)

Maya, M.V.; Karapurkar, S.G.; Naik, H.; Roy, R.; Shenoy, D.M.; Naqvi, S.W.A.

receives large runoff from land during the SW monsoon and the associated terrestrial organic matter inputs may possibly play a role in biogeochemical cycling. 2 Methods 2.1 Sampling Time series measurements were carried out at the Candolim Time Series (CaTS...) station (aka Sta. G5), which is located CaTS~10 km Fig. 1. Map of the study area showing the location of Candolim Time Series (CaTS) station (G5) off Goa. at Lat. 15◦31prime N, Long. 73◦39prime E, approximately 10 km off Candolim Beach (Goa), central...

Tritium in organic matter around Krsko Nuclear Power Plant

International Nuclear Information System (INIS)

Kristof, Romana; Zorko, Benjamin; Kozar Logar, Jasmina; Kosenina, Suzana

2017-01-01

The aim of the research was to obtain first results of tritium in the organic matter of environmental samples in the vicinity of Krsko NPP. The emphasis was on the layout of suitable sampling network of crops and fruits in nearby agricultural area. Method for determination of tritium in organic matter in the form of Tissue Free Water Tritium (TFWT) and Organically Bound Tritium (OBT) has been implemented. Capabilities of the methods were tested on real environmental samples and its findings were compared to modeled activities of tritium from atmospheric releases and literature based results of TFWT and OBT. (author)

Heavy metal analysis of suspended particulate matter (SPM) and other samples from some workplaces in Kenya

International Nuclear Information System (INIS)

Kinyua, A.M.; Gatebe, C.K.; Mangala, M.J.

1998-01-01

Air pollution studies in Nairobi are indicating a rising trend in the particulate matter loading. The trend is mainly attributed to increased volume of motor vehicles, the physical change of the environment, agricultural and industrial activities. In this study, total suspended particulate matter sampling at the Nairobi industrial area and inside one workplace are reported. Included also are the results of analysis of water samples and effluents collected from a sugar factory, a tannery, and mercury (Hg) analysis in some beauty creams sold in Nairobi. The samples were analysed for heavy metal content using Energy Dispersive X-ray Fluorescence (EDXRF) while the suspended particulate matter (SPM) concentrations were determined by gravimetric technique. Total reflection x-ray fluorescence (TRXF), atomic absorption spectrophotometry and PIXE analytical techniques plus the use of Standard and Certified Reference Materials (SRM's and CRM's) were used for quality control, analysis and evaluation of the accrued data. Air sampling in the industrial area was done twice (Wednesday and Saturday) every week for a period of two months (November and December, 1996) and twice monthly for a period of six months (January-June 1997). Each sample covering approximately 24 hours, was collected using the 'Gent' Stacked Filter Unit (SFU), for day and night times. The SPM were found to vary from 16 to 83 mgm -3 during the sampling period. The analysis of dust collected inside a workplace showed that there was poor filtration of the air pumped into the building and that there was a need for improvement of the air conditioning unit plus reduction of emissions from a neighbouring tyre factory. Beauty creams analysed showed that there is some mercury present in significant amounts (0.14 - 3.0%). The results of these mercury levels are presented for various brands of cosmetics sold in some market outlets in Nairobi. The health implications on the presence of mercury in some of these beauty

Rare earth elements in suspended and bottom sediments of the Mandovi estuary,central west coast of India: Influence of mining

Digital Repository Service at National Institute of Oceanography (India)

Shynu, R.; Rao, V.P.; Kessarkar, P.M.; Rao, T.G.

Rare earth elements (REEs) in the suspended particulate matter (SPM) of the Mandovi estuary indicated that the mean total-REEs and light REE to heavy REE ratios are lower than that of the average suspended sediment in World Rivers and Post...

Colored dissolved organic matter in Tampa Bay, Florida

Science.gov (United States)

Chen, Z.; Hu, C.; Conmy, R.N.; Muller-Karger, F.; Swarzenski, P.

2007-01-01

Absorption and fluorescence of colored dissolved organic matter (CDOM) and concentrations of dissolved organic carbon (DOC), chlorophyll and total suspended solids in Tampa Bay and its adjacent rivers were examined in June and October of 2004. Except in Old Tampa Bay (OTB), the spatial distribution of CDOM showed a conservative relationship with salinity in June, 2004 (aCDOM(400) = − 0.19 × salinity + 6.78, R2 = 0.98, n = 17, salinity range = 1.1–32.5) with little variations in absorption spectral slope and fluorescence efficiency. This indicates that CDOM distribution was dominated by mixing. In October, 2004, CDOM distribution was nonconservative with an average absorption coefficient (aCDOM(400), ∼ 7.76 m-1) about seven times higher than that in June (∼ 1.11 m-1). The nonconservative behavior was caused largely by CDOM removal at intermediate salinities (e.g., aCDOM(400) removal > 15% at salinity ∼ 13.0), which likely resulted from photobleaching due to stronger stratification. The spatial and seasonal distributions of CDOM in Tampa Bay showed that the two largest rivers, the Alafia River (AR) and Hillsborough River (HR) were dominant CDOM sources to most of the bay. In OTB, however, CDOM showed distinctive differences: lower absorption coefficient, higher absorption spectral slopes, and lower ratios of CDOM absorption to DOC and higher fluorescence efficiency. These differences may have stemmed from (1) changes in CDOM composition by more intensive photobleaching due to the longer residence time of water mass in OTB; (2) other sources of CDOM than the HR/AR inputs, such as local creeks, streams, groundwater, and/or bottom re-suspension. Average CDOM absorption in Tampa Bay at 443 nm, aCDOM(443), was about five times higher in June and about ten times higher in October than phytoplankton pigment absorption, aph(443), indicating that blue light attenuation in the water column was dominated by CDOM rather than by phytoplankton absorption throughout the

Characteristics of dissolved organic matter following 20 years of peatland restoration

NARCIS (Netherlands)

Höll, B.S.; Fiedler, S.; Jungkunst, H.F.; Kalbitz, K.; Freibauer, A.; Drösler, M.; Stahr, K.

2009-01-01

The changes in the amounts and composition of dissolved organic matter (DOM) following long-term peat restoration are unknown, although this fraction of soil organic matter affects many processes in such ecosystems. We addressed this lack of knowledge by investigating a peatland in south-west

Organochlorine pesticides in surface sediments and suspended particulate matters from the Yangtze estuary, China

International Nuclear Information System (INIS)

Liu Min; Cheng Shubo; Ou Dongni; Yang Yi; Liu Hualin; Hou Lijun; Gao Lei; Xu Shiyuan

2008-01-01

Total HCHs' and total DDTs' levels in surface sediments (SS) ranged from 0.5 to 17.5 ng g -1 and from 0.9 to 33.1 ng g -1 , averaged 6.0 and 8.2 ng g -1 , respectively. Total HCHs' and total DDTs' levels in suspended particulate matters (SPM) varied from 6.2 to 14.8 ng g -1 with a mean value of 12.3 ng g -1 and were from 3.4 to 25.7 ng g -1 with an average of 16.4 ng g -1 , respectively. Lindane is the main HCHs' source and continuing use in the Yangtze Delta areas of 'pure' γ-HCH (lindane) rather than technical HCH (a mix of largely α- and some γ-HCH). DDTs in SS are mainly accumulated in history. However, high DDT fractions in SPM are indicators of new input of typical dicofol type DDT from 2002 to 2004. It can be seen that most samples from the Yangtze estuary were in ranges where adverse biological effects are expected, either occasionally or frequently. - SPM, more polluted than SS, had similar contaminant composition. New input of lindane and typical dicofol type DDT were found and Yangtze estuary had been affected adversely

Production of Dissolved Organic Matter During Doliolid Feeding

Science.gov (United States)

Castellane, N. J.; Paffenhofer, G. A.; Stubbins, A.

2016-02-01

The biological carbon pump (BCP) draws carbon dioxide out of the atmosphere and buries it at the seafloor. The efficiency of the BCP is determined in part by the sinking rates of particulate organic carbon (POC) from ocean surface waters. Zooplankton can package POC into fecal pellets with higher sinking rates than their food source (e.g. phytoplankton), increasing the efficiency of the BCP. However, dissolved organic carbon (DOC) is also produced as zooplankton ingest and egest food, reducing the efficiency of BCP. The pelagic tunicate Dolioletta gegenbauri (doliolid) is a gelatinous zooplankton found at high concentrations in shelf waters, including our study site: the South Atlantic Bight. Doliolids are efficient grazers capable of stripping large quantities of phytoplankton from the water column. To determine the balance between pellet formation and DOC production during feeding, doliolids (6-7 mm gonozooids) were placed in natural seawater amended with a live phytoplankton food source and incubated on a plankton wheel. Dissolved organic matter (DOM) released directly to the water as well as the water soluble fraction of pellet organic matter were quantified and optically characterized. Colored dissolved organic matter (CDOM) absorbance and fluorescence spectra revealed that doliolid feeding produces DOM with optical properties that are commonly indicative of newly produced, highly biolabile DOM of microbial origin. Based upon these optical characteristics, doliolid-produced DOM is expected to be highly bio-labile in the environment and therefore rapidly degraded by surface ocean microbes shunting phytoplankton-derived organic carbon out of the BCP and back to dissolved inorganic carbon.

Vertical transport of organic matter in the various oceanic areas

International Nuclear Information System (INIS)

Handa, Nobuhiko; Hayakawa, Kazuhide

1993-01-01

Organic matter produced by the photosynthesis of the phytoplankton is removed from the euphotic layer to the underlying waters by sinking of the particles consisting of both marine snow and fecal pellet. Phytoplankton bloom always enhances the vertical flux of organic matter from the subsurface to deep waters. Turbidity current is another factor to govern the vertical flux of organic carbon especially in the continental shelf to its slope areas. However, no information are available to distinguish the organic materials from these two sources. Stable carbon isotope ratio and fatty acid composition give most promising informations to diagnose the physiological state of the phytoplankton which is one of the source of the organic materials of the sinking particle, because of the extensive variations of the δ 13 C of the phytoplankton cellular organic matter and fatty acid composition due to the phytoplankton growth rate (O'Leary, 1981; Morris et al., 1985). Δ 14 C of the organic matter of the sinking particle will provide an information as to how much organic materials are derived from the phytoplankton growing in the surface and subsurface waters and/or from the resuspended particles of the surface sediment in the continental shelf and its slope areas. Recently we analyzed various samples of the sinking particles collected from the coastal areas of the Antarctica and off Hokkaido, Japan for fatty acids and found that ratios as biomarker to diagnose these growth phases of the phytoplankton growing in the surface to subsurface waters. Thus, we intend to report here these data obtained. (J.P.N.)

(Tropical) soil organic matter modelling: problems and prospects

NARCIS (Netherlands)

Keulen, van H.

2001-01-01

Soil organic matter plays an important role in many physical, chemical and biological processes. However, the quantitative relations between the mineral and organic components of the soil and the relations with the vegetation are poorly understood. In such situations, the use of models is an

Mapping Soil Organic Matter with Hyperspectral Imaging

Science.gov (United States)

Moni, Christophe; Burud, Ingunn; Flø, Andreas; Rasse, Daniel

2014-05-01

Soil organic matter (SOM) plays a central role for both food security and the global environment. Soil organic matter is the 'glue' that binds soil particles together, leading to positive effects on soil water and nutrient availability for plant growth and helping to counteract the effects of erosion, runoff, compaction and crusting. Hyperspectral measurements of samples of soil profiles have been conducted with the aim of mapping soil organic matter on a macroscopic scale (millimeters and centimeters). Two soil profiles have been selected from the same experimental site, one from a plot amended with biochar and another one from a control plot, with the specific objective to quantify and map the distribution of biochar in the amended profile. The soil profiles were of size (30 x 10 x 10) cm3 and were scanned with two pushbroomtype hyperspectral cameras, one which is sensitive in the visible wavelength region (400 - 1000 nm) and one in the near infrared region (1000 - 2500 nm). The images from the two detectors were merged together into one full dataset covering the whole wavelength region. Layers of 15 mm were removed from the 10 cm high sample such that a total of 7 hyperspectral images were obtained from the samples. Each layer was analyzed with multivariate statistical techniques in order to map the different components in the soil profile. Moreover, a 3-dimensional visalization of the components through the depth of the sample was also obtained by combining the hyperspectral images from all the layers. Mid-infrared spectroscopy of selected samples of the measured soil profiles was conducted in order to correlate the chemical constituents with the hyperspectral results. The results show that hyperspectral imaging is a fast, non-destructive technique, well suited to characterize soil profiles on a macroscopic scale and hence to map elements and different organic matter quality present in a complete pedon. As such, we were able to map and quantify biochar in our

New Approaches in Soil Organic Matter Fluorescence; A Solid Phase Fluorescence Approach

Science.gov (United States)

Bowman, M. M.; Sanclements, M.; McKnight, D. M.

2017-12-01

Fluorescence spectroscopy is a well-established technique to investigate the composition of organic matter in aquatic systems and is increasingly applied to soil organic matter (SOM). Current methods require that SOM be extracted into a liquid prior to analysis by fluorescence spectroscopy. Soil extractions introduce an additional layer of complexity as the composition of the organic matter dissolved into solution varies based upon the selected extractant. Water is one of the most commonly used extractant, but only extracts the water-soluble fraction of the SOM with the insoluble soil organic matter fluorescence remaining in the soil matrix. We propose the use of solid phase fluorescence on whole soils as a potential tool to look at the composition of organic matter without the extraction bias and gain a more complete understand of the potential for fluorescence as a tool in terrestrial studies. To date, the limited applications of solid phase fluorescence have ranged from food and agriculture to pharmaceutical with no clearly defined methods and limitations available. We are aware of no other studies that use solid phase fluorescence and thus no clear methods to look at SOM across a diverse set of soil types and ecosystems. With this new approach to fluorescence spectroscopy there are new challenges, such as blank correction, inner filter effect corrections, and sample preparation. This work outlines a novel method for analyzing soil organic matter using solid phase fluorescence across a wide range of soils collected from the National Ecological Observatory Network (NEON) eco-domains. This method has shown that organic matter content in soils must be diluted to 2% to reduce backscattering and oversaturation of the detector in forested soils. In mineral horizons (A) there is observed quenching of the humic-like organic matter, which is likely a result of organo-mineral complexation. Finally, we present preliminary comparisons between solid and liquid phase

Elucidating Microbial Species-Specific Effects on Organic Matter Transformation in Marine Sediments

Science.gov (United States)

Mahmoudi, N.; Enke, T. N.; Beaupre, S. R.; Teske, A.; Cordero, O. X.; Pearson, A.

2017-12-01

Microbial transformation and decomposition of organic matter in sediments constitutes one of the largest fluxes of carbon in marine environments. Mineralization of sedimentary organic matter by microorganisms results in selective degradation such that bioavailable or accessible compounds are rapidly metabolized while more recalcitrant, complex compounds are preserved and buried in sediment. Recent studies have found that the ability to use different carbon sources appears to vary among microorganisms, suggesting that the availability of certain pools of carbon can be specific to the taxa that utilize the pool. This implies that organic matter mineralization in marine environments may depend on the metabolic potential of the microbial populations that are present and active. The goal of our study was to investigate the extent to which organic matter availability and transformation may be species-specific using sediment from Guaymas Basin (Gulf of California). We carried out time-series incubations using bacterial isolates and sterilized sediment in the IsoCaRB system which allowed us to measure the production rates and natural isotopic signatures (δ13C and Δ14C) of microbially-respired CO2. Separate incubations using two different marine bacterial isolates (Vibrio sp. and Pseudoalteromonas sp.) and sterilized Guaymas Basin sediment under oxic conditions showed that the rate and total quantity of organic matter metabolized by these two species differs. Approximately twice as much CO2 was collected during the Vibrio sp. incubation compared to the Pseudoalteromonas sp. incubation. Moreover, the rate at which organic matter was metabolized by the Vibrio sp. was much higher than the Pseudoalteromonas sp. indicating the intrinsic availability of organic matter in sediments may depend on the species that is present and active. Isotopic analyses of microbially respired CO2 will be used to constrain the type and age of organic matter that is accessible to each species

Peatland use and transport of particulate organic matter in boreal headwater catchments

Science.gov (United States)

Marttila, Hannu; Karjalainen, Satu-Maaria; Nieminen, Mika; Kløve, Bjørn

2014-05-01

Peatland use can cause increased transport of particulate organic matter (POM) causing deteriorated water quality and especially siltation of stream beds. Even though topic has gained major attention among stakeholders it has received only minor efforts to solve the main sources and properties of transported particles. The development of effective management practices and evaluation of purification efficiency demands understanding of the sources of particulate matter in peat dominated catchments with various land uses and hydrological conditions. The objectives of this study were: (1) to determinate physical properties of POM in headwater brooks affected by different peatland uses, and; (2) to identity the sources of transported material by using sediment fingerprinting methods. For this purpose, two headwater catchments under peat extraction and peatland forestry land uses with 8 sampling points were monitored for 2 years using time integrated suspended sediment samplers. Data was completed by gap samples from 50 other headwater locations with different upstream land uses: pristine, peatland forestry and peat extraction. For the sources analysis, disturbed topsoil, stream bed sediment, banks of ditches and brooks, algae and various vegetation types were identified as the potential sediment sources. Stable isotopes (δ13C, δ15N) and C/N ratio were analyzed to discriminate between the possible sources. Results are further scaled against different land uses, landscape elements and seasonal hydrological conditions in headwaters. This paper presents the preliminary results from a two year study aiming to show various patterns in transport of POM in boreal headwater catchments. Due to strong land-water relationship in headwaters, further information on the properties of particles is needed to assess the downstream impacts of land use.

Multi-technical approach to characterize the dissolved organic matter from clay-stone

International Nuclear Information System (INIS)

Blanchart, Pascale; Michels, Raymond; Faure, Pierre; Parant, Stephane; Bruggeman, Christophe; De Craen, Mieke

2012-01-01

Document available in extended abstract form only. Currently, different clay formations (Boom Clay, Callovo-Oxfordian argilites, Opalinus Clay, Toarcian shales...) are studied as reference host rocks for methodological studies on the geological disposal of high-level and long-lived radioactive waste. While a significant effort is being done on the characterization of the mineral composition and the reactivity of the clays as barriers, the occurrence of organic matter, even in low proportion cannot be neglected. The organic matter appears as gas (C 1 -C 4 as identified in the Bure underground facilities), as solid (kerogen), as hydrocarbon liquids (free hydrocarbons within the kerogen or adsorbed on minerals) as well as in the aqueous phase (Dissolved Organic Matter - DOM). DOM raises specific interest, as it may have complexation properties towards metals and rare earth elements and is potentially mobile. Therefore, it is important to characterize the DOM as part of a study of feasibility of geological disposal. In this study, four host rocks were studied: - The Callovo-Oxfordian shales of Bure Underground Research Laboratory (Meuse, France); - The Opalinus Clay of Mont Terri Underground Research Laboratory (Switzerland); - The Toarcian shales of Tournemire (Aveyron, France); - The Boom Clay formation studied in The HADES Underground Research Laboratory (Mol, Belgium). Organic matter characteristics vary upon formation in terms of (i) origin (mainly marine type II; mixtures of marine type II and higher plants type III organic matter often poorly preserved), (ii) TOC contents, (iii) thermal maturity (for instance, Opalinus Clay and Toarcian shales are more mature and have poor oxygen content compare to Callovo-Oxfordian shales and Boom Clay). These differences in organic matter quality may have an influence on the quantity and the quality of DOM. The DOM of the rocks was isolated by Soxhlet extraction using pure water. A quantitative and qualitative multi

Spatial and temporal distribution of metals in suspended particulate matter of the Kali estuary, India

Science.gov (United States)

Suja, S.; Kessarkar, Pratima M.; Fernandes, Lina L.; Kurian, Siby; Tomer, Arti

2017-09-01

Major (Al, Fe, Mn, Ti, Mg) and trace (Cu, Zn, Pb, Cr, Ni, Co, Zr, Rb, Sr, Ba, Li, Be, Sc, V, Ga, Nb, Mo, Sn, Sb, Cs, Hf, Ta, Bi, Th, U) elements and particulate organic carbon (POC) concentrations in surface suspended particulate matter (SPM) of the Kali estuary, (central west coast of India) were studied during the pre-monsoon, monsoon and post monsoon seasons to infer estuarine processes, source of SPM and Geoaccumulation Index (Igeo) assigned pollutionIgeo levels. Distribution of SPM indicates the presence of the estuarine turbidity maximum (ETM) during all three seasons near the river mouth and a second ETM during the post monsoon time in the upstream associated with salinities gradient. The SPM during the monsoon is finer grained (avg. 53 μm), characterized by uniformly low normalized elemental concentration, whereas the post and pre monsoon are characterized by high normalized elemental concentration with coarser grain size (avg. 202 μm and 173 μm respectively) with highest ratios in the upstream estuary. The elemental composition and principal component analysis for the upstream estuary SPM support more contribution from the upstream catchment area rocks during the monsoon season; there is additional contribution from the downstream catchment area during the pre and post monsoon period due to the tidal effect. The Kali estuarine SPM has higher Al, Fe, Mn, Ti, Mg, Ni, Co, Ba, Li and V with respect to Average World River SPM (WRSPM). Igeo values for the SPM indicate Kali Estuary to be severely enriched with Mn and moderately enriched with Cu, Zn, Ni, Co, U and Mo in the upstream estuary during pre and post monsoon seasons. Seasonal changes in salinity gradient (reduced freshwater flow due to closing of the dam gates), reduced velocity at meandering region of the estuary and POC of 1.6-2.3% resulted in co-precipitation of trace elements that were further fortified by flocculation and coagulation throughout the water column resulting in metal trapping in the

Organic Compounds, Trace Elements, Suspended Sediment, and Field Characteristics at the Heads-of-Tide of the Raritan, Passaic, Hackensack, Rahway, and Elizabeth Rivers, New Jersey, 2000-03

Science.gov (United States)

Bonin, Jennifer L.; Wilson, Timothy P.

2006-01-01

Concentrations of suspended sediment, particulate and dissolved organic carbon, trace elements, and organic compounds were measured in samples from the heads-of-tide of the five tributaries to the Newark and Raritan Bays during June 2000 to June 2003. The samples were collected as part of the New Jersey Department of Environmental Protection Toxics Reduction Workplan/Contaminant Assessment Reduction Program. Samples of streamwater were collected at water-quality sampling stations constructed near U.S. Geological Survey gaging stations on the Raritan, Passaic, Hackensack, Rahway, and Elizabeth Rivers. Sampling was conducted during base-flow conditions and storms. Constituent concentrations were measured to determine the water quality and to calculate the load of sediment and contaminants contributed to the bays from upstream sources. Water samples were analyzed for suspended sediment, dissolved organic carbon, particulate organic carbon, and specific conductance. Samples of suspended sediment and water were analyzed for 98 distinct polychlorinated biphenyl congeners, 7 dioxins, 10 furans, 27 pesticides, 26 polycyclic aromatic hydrocarbons, and the trace elements cadmium, lead, mercury, and methyl-mercury. Measurements of ultra-low concentrations of organic compounds in sediment and water were obtained by collecting 1 to 3 grams of suspended sediment on glass fiber filters and by passing at least 20 liters of filtered water through XAD-2 resin. The extracted sediment and XAD-2 resin were analyzed for organic compounds by high- and low-resolution gas chromatography mass-spectrometry that uses isotope dilution procedures. Trace elements in filtered and unfiltered samples were analyzed for cadmium, lead, mercury, and methyl-mercury by inductively coupled charged plasma and mass-spectrometry. All constituent concentrations are raw data. Interpretation of the data will be completed in the second phase of the study.

Energy Transformations of Soil Organic Matter in a Changing World

Science.gov (United States)

Herrmann, A. M.; Coucheney, E.; Grice, S. M.; Ritz, K.; Harris, J.

2011-12-01

The role of soils in governing the terrestrial carbon balance is acknowledged as being important but remains poorly understood within the context of climate change. Soils exchange energy with their surroundings and are therefore open systems thermodynamically, but little is known how energy transformations of decomposition processes are affected by temperature. Soil organic matter and the soil biomass can be conceptualised as analogous to the 'fuel' and 'biological engine' of the earth, respectively, and are pivotal in driving the belowground carbon cycle. Thermodynamic principles of soil organic matter decomposition were evaluated by means of isothermal microcalorimetry (TAM Air, TA Instruments, Sollentuna Sweden: (i) Mineral forest soils from the Flakaliden long-term nitrogen fertilisation experiment (Sweden) were amended with a range of different substrates representing structurally simple to complex, ecologically pertinent organic matter and heat signatures were determined at temperatures between 5 and 25°C. (ii) Thermodynamic and resource-use efficiencies of the biomass were determined in arable soils which received contrasting long-term management regimes with respect to organic matter and nitrogen since 1956. The work showed that (i) structurally labile components have higher activation energy and temperature dependence than structurally more complex organic components. This is, however, in contrast to the thermodynamic argument which suggests the opposite that reactions metabolising structurally complex, aromatic components have higher temperature dependence than reactions metabolising structurally more labile components. (ii) Microbial communities exposed to long-term stress by heavy metal and low pH were less thermodynamic efficient and showed a decrease in resource-use efficiency in comparison with conventional input regimes. Differences in efficiencies were mirrored in both the phenotypic and functional profiles of the communities. We will present our

Cosorption study of organic pollutants and dissolved organic matter in a soil

Energy Technology Data Exchange (ETDEWEB)

Flores-Cespedes, F. [Department of Inorganic Chemistry, University of Almeria, La Canada de San Urbano s/n, 04120 Almeria (Spain); Fernandez-Perez, M. [Department of Inorganic Chemistry, University of Almeria, La Canada de San Urbano s/n, 04120 Almeria (Spain)]. E-mail: mfernand@ual.es; Villafranca-Sanchez, M. [Department of Inorganic Chemistry, University of Almeria, La Canada de San Urbano s/n, 04120 Almeria (Spain); Gonzalez-Pradas, E. [Department of Inorganic Chemistry, University of Almeria, La Canada de San Urbano s/n, 04120 Almeria (Spain)

2006-08-15

In this study we have evaluated the effects of dissolved organic matter (DOM) on sorption of imidacloprid, 3,4-dichloroaniline (3,4-DCA) and 4-bromoaniline (4-BA) on a typical calcareous soil (Luvic Xerosol) from south-eastern Spain. Two different types of DOM were used, that is to say, dissolved natural organic matter extracts from a commercial peat (DNOM) and a high-purity tannic acid (TA) solution. The experiments were carried out in a 0.01 M CaCl{sub 2} aqueous medium at 25 deg. C. The results indicated that the presence of both DNOM and TA, over a concentration range of 15-100 mg L{sup -1}, produced an increase in the amount of 3,4-DCA and 4-BA sorbed and a decrease in the amount of imidacloprid retained on the soil studied. A modified distribution coefficient, K {sub doc}, has been proposed as a safer parameter for soil sorption predictions of organic pollutants and it could be of help to model the fate of these in the environment. - Cosorption of organic pollutants and DOM.

Cosorption study of organic pollutants and dissolved organic matter in a soil

International Nuclear Information System (INIS)

Flores-Cespedes, F.; Fernandez-Perez, M.; Villafranca-Sanchez, M.; Gonzalez-Pradas, E.

2006-01-01

In this study we have evaluated the effects of dissolved organic matter (DOM) on sorption of imidacloprid, 3,4-dichloroaniline (3,4-DCA) and 4-bromoaniline (4-BA) on a typical calcareous soil (Luvic Xerosol) from south-eastern Spain. Two different types of DOM were used, that is to say, dissolved natural organic matter extracts from a commercial peat (DNOM) and a high-purity tannic acid (TA) solution. The experiments were carried out in a 0.01 M CaCl 2 aqueous medium at 25 deg. C. The results indicated that the presence of both DNOM and TA, over a concentration range of 15-100 mg L -1 , produced an increase in the amount of 3,4-DCA and 4-BA sorbed and a decrease in the amount of imidacloprid retained on the soil studied. A modified distribution coefficient, K doc , has been proposed as a safer parameter for soil sorption predictions of organic pollutants and it could be of help to model the fate of these in the environment. - Cosorption of organic pollutants and DOM

Test procedure for determining organic matter content in soils : UV-VIS method.

Science.gov (United States)

2010-11-01

The Texas Department of Transportation has been having problems with organic matter in soils that they : stabilize for use as subgrade layers in road construction. The organic matter reduces the effectiveness of : common soil additives (lime/cement) ...

Tracing organic matter sources in a tropical lagoon of the Caribbean Sea

Science.gov (United States)

Alonso-Hernández, Carlos M.; Garcia-Moya, Alejandro; Tolosa, Imma; Diaz-Asencio, Misael; Corcho-Alvarado, Jose Antonio; Morera-Gomez, Yasser; Fanelli, Emanuela

2017-09-01

The natural protected lagoon of Guanaroca, located between Cienfuegos Bay and the Arimao River, Cuba, has been heavily impacted by human-induced environmental changes over the past century. Sources of organic matter in the Guanaroca lagoon and concentrations of radioisotopes (210Pb, 226Ra, 137Cs and 239,240Pu), as tracers of anthropogenic impacts, were investigated in a 78 cm sediment core. Variations in total organic carbon (TOC), total nitrogen (TN), stable isotopic composition (δ13C and δ15N) and ratio of total organic carbon to total nitrogen (C/N) were analysed. On such a basis, environmental changes in the lagoon were revealed. Down core variation patterns of the parameters representing sources of organic matter were predominantly related to the impacts of human activities. Up to the nineteenth century, the principal sources of organic matter to sediments (more than 80%) were a mixing of terrestrial vascular plants ( 48%) and freshwater phytoplankton ( 8%), with minimal contribution from the marine component ( 16%). In the period 1900-1980, due to the strong influence of human activities in the catchment area, the water exchange capacity of the lagoon declined substantially, as indicated by the relatively high proportion of organic matter originated from human activities (58%). Since 1980, as a result of management actions in the protected area, the lagoon has regained gradually its capability to exchange freshwater, showing sources of organic matter similar to the natural conditions recorded previous to 1900, although an indication of human impact (treated sewage contributed for 26% to the organic matter in sediments) was still observed and further management measures would be required.

Organic matter and the geotechnical properties of submarine sediments

Science.gov (United States)

Keller, George H.

1982-09-01

Continental slope deposits off Peru and Oregon where coastal upwelling is a pronounced oceanographic process possess significant concentrations of organic carbon. Geotechnical properties are altered to varying degrees by the organic matter. Organic matter absorbs water and causes clay-size particles to aggregate forming an open fabric. This causes unusually high water contents and plasticity and exceptionally low wet bulk densities. Some of these deposits show notable increases in shear strength, sensitivity and degree of apparent overconsolidation. Owing to the unique geotechnical properties, sediment stability characteristics are considered to be poor in situations of excess pore pressures. Failure appears to take the form of a fluidized flow somewhat similar to the quick clays of Scandinavia.

The effect of Hurricane Lili on the distribution of organic matter along the inner Louisiana shelf (Gulf of Mexico, USA)

Science.gov (United States)

Goñi, Miguel A.; Gordon, Elizabeth S.; Monacci, Natalie M.; Clinton, Rebecca; Gisewhite, Rachel; Allison, Mead A.; Kineke, Gail

2006-11-01

On October 3, 2002 Hurricane Lili made landfall on a previously studied region of the inner Louisiana shelf as a Category 2 storm with winds over 160 km/h. A week after the hurricane, major impacts of the storm were not evident in the water column except for the lower than expected inshore salinities (˜12 psu) for this time of year, which was characterized by low river discharge. Turbidity profiles were typical of those measured during previous investigations with suspended sediment concentrations >75 mg/L at inshore stations and <50 mg/L in surface waters and offshore. The implication is that the sediments resuspended during the hurricane settled soon after the storm passage. Water column particulate organic carbon (POC) concentrations ranged from 0.1 to over 2.0 mg/L, with the highest concentrations measured near the seabed and in the inshore portions of the study area. Suspended particles were characterized by low organic matter content (%POC of 0.5-2 wt%), low chlorophyll:POC ratios (Chl:POC<4 mg/g) and moderately elevated POC:particulate nitrogen ratios (POC:PN of 10-14 mol/mol), all suggesting their source was locally resuspended seabed sediment rather than from algal biomass or land-derived vascular plant detritus. Post hurricane sediment deposition throughout the study area resulted in a storm layer that ranged from <0.5 to 20 cm in thickness. In most locations sediment accumulation ranged from 3 to 10 cm. The storm deposits were generally composed of silty clays with a coarser, somewhat sandy 1-2 cm basal layer. Surface sediments from the storm layer were characterized by relatively high mineral surface areas (SA of 30-50 m 2/g) and elevated OC contents (%OC of 1.0-2.0%). The dispersal of fine sediments following the hurricane resulted in marked changes in the SA and %OC values of surface sediments from offshore locations, which prior to the storm contained coarser, organic-poor particles (SA of 5-15 m 2/g and %OC of 0.2-0.6%). The OC:SA and OC:N ratios

Interactions of diuron with dissolved organic matter from organic amendments.

Science.gov (United States)

Thevenot, Mathieu; Dousset, Sylvie; Hertkorn, Norbert; Schmitt-Kopplin, Philippe; Andreux, Francis

2009-07-01

Diuron is frequently detected in some drinking water reservoirs under the Burgundy vineyards, where organic amendments are applied. The environmental effect of these amendments on pesticide transport is ambiguous: on the one hand it could enhance their retention by increasing soil organic carbon content; on the other hand, dissolved organic matter (DOM) could facilitate their transport. Elutions were performed using columns packed with glass beads in order to investigate DOM-diuron interactions, and the possible co-transport of diuron and DOM. Four organic amendments (A, B, C and D) were tested; C and D were sampled at fresh (F) and mature (M) stages. An increase in diuron leaching was observed only for A and D(F) amendments (up to 16% compared to the DOM-free blank samples), suggesting a DOM effect on diuron transport. These results could be explained by the higher DOM leaching for A and D(F) compared to B, C(F), C(M) and D(M) increasing diuron-DOM interactions. These interactions seem to be related to the aromatic and aliphatic content of the DOM, determining formation of hydrogen and non-covalent bonds. The degree of organic matter maturity does not seem to have any effect with amendment C, while a reduction in diuron leaching is observed between D(F) and D(M). After equilibrium dialysis measurement of diuron-DOM complexes, it appeared that less than 3% of the diuron applied corresponded to complexes with a molecular weight >1000 Da. Complexes <1000 Da could also take part in this facilitated transport.

Circulation during Storms and Dynamics of Suspended Matter in a Sheltered Coastal Area

Directory of Open Access Journals (Sweden)

Francesco Paladini de Mendoza

2018-04-01

Full Text Available The Gulf of Gaeta, in the western margin of central Italy, is characterized by a coastal morphology that creates a natural sheltered area in which fine sediment settles. The new port regulatory plan provides for dock expansions and dredging works that could alter the suspended particulate matter (SPM concentration. The present study investigates the dynamics of the Gulf of Gaeta with a focus on the dynamic processes that affect the fine particle concentration. The study was conducted through a multidisciplinary approach that involves remote sensing acquisitions (satellite imagery and X-band radar, measurements in situ (water sampling, wave buoy, weather station, turbidity station, CTD profiles, and numerical modelling (SWAN and Delft3D FLOW. The X-band radar system supports the analysis of the dynamic processes of the SPM concentration providing a large dataset useful for the hydrodynamic model’s validation. The analysis reveals a strong influence of nearby rivers in modulating the SPM at the regional scale. Short-term high and low fluctuations in SPM concentration within the gulf are triggered by the local effect of the main physical forces. In particular, the direction of events and bottom sediment resuspension play a key role in modulating the SPM concentration while micro-tidal regime does not appear to influence turbidity in the study area. This approach represents an important tool in improving the long-term coastal management strategy from the perspective of sustainable human activities in marine coastal ecosystems.

Presence and evolution of natural organic matter in the boom clay

International Nuclear Information System (INIS)

Van Geet, M.; Deniau, I.; Largeau, C.; Bruggeman, C.; Maes, A.; Dierckx, A.

2004-01-01

Because of its very low hydraulic conductivity, reducing conditions, slightly alkaline pH, high specific surface, high cation exchange capacity and high plasticity, the Boom Clay is studied as a reference host formation for the deep disposal of high-level long-lived radioactive waste (NIRAS/ONDRAF, 1989). However, Boom Clay also contains up to 5% wt. of organic matter (OM). As radionuclides can form complexes with this organic matter, a detailed characterisation and knowledge of the evolution of the organic matter is necessary. An overview of the characteristics of the organic matter present in Boom Clay is given by Van Geet et al., (2003). The solid phase OM can be up to 5%. The dissolved OM fraction is around 200 mg C per liter of Boom Clay pore water. Both kinds of OM will be discussed. Concerning the solid phase OM the focus will be on the past evolution and its possible future evolution due to a thermal stress. For the dissolved OM, the focus will be on its origin. (author)

Organic matter in the universe

CERN Document Server

Kwok, Sun

2012-01-01

Authored by an experienced writer and a well-known researcher of stellar evolution, interstellar matter and spectroscopy, this unique treatise on the formation and observation of organic compounds in space includes a spectroscopy refresher, as well as links to geological findings and finishes with the outlook for future astronomical facilities and solar system exploration missions. A whole section on laboratory simulations includes the Miller-Urey experiment and the ultraviolet photolysis of ices.

Leader Election and Shape Formation with Self-Organizing Programmable Matter

OpenAIRE

Daymude, Joshua J.; Derakhshandeh, Zahra; Gmyr, Robert; Strothmann, Thim; Bazzi, Rida; Richa, Andréa W.; Scheideler, Christian

2015-01-01

We consider programmable matter consisting of simple computational elements, called particles, that can establish and release bonds and can actively move in a self-organized way, and we investigate the feasibility of solving fundamental problems relevant for programmable matter. As a suitable model for such self-organizing particle systems, we will use a generalization of the geometric amoebot model first proposed in SPAA 2014. Based on the geometric model, we present efficient local-control ...

Non-invasive localization of organic matter in soil aggregates using SR-μCT

Science.gov (United States)

Peth, Stephan; Mordhorst, Anneka; Chenu, Claire; Uteau Puschmann, Daniel; Garnier, Patricia; Nunan, Naoise; Pot, Valerie; Beckmann, Felix; Ogurreck, Malte

2014-05-01

Knowledge of the location of soil organic matter (SOM) and its spatial association to soil structure is an important step in improving modeling approaches for simulating organic matter turnover processes. Advanced models for carbon mineralization are able to account for the 3D distribution of SOM which is assumed to influence mineralisation. However, their application is still limited by the fact that no method exists to non-invasively determine the 3D spatial distribution of SOM in structured soils. SR-based X-ray microtomography (SR-µCT) is an advanced and promising tool in gaining knowledge on the 3-dimensional organization of soil phases (minerals, organic matter, water, air) which on a voxel level could be implemented into spatially explicit models. However, since the contrast of linear attenuation coefficients of soil organic matter on the one hand and mineral components and water on the other hand are relatively low, especially when materials are finely dispersed, organic matter within the soil pore space is often not resolved in ordinary X-ray absorption contrast imaging. To circumvent this problem we have developed a staining procedure for organic matter using Osmium-tetroxide since Osmium is an element with an absorption edge at a higher X-ray energy level. Osmium is known from transmission electron microscopy analysis (TEM) to stain organic matter specifically and irreversibly while having an absorption edge at approximately 74 keV. We report on the application of a novel Osmium vapor staining method to analyze differences in organic matter content and identify small scale spatial distribution of SOM in soil aggregates. To achieve this we have taken soil aggregate samples (6-8 mm across) obtained from arable soils differing in soil management. Aggregate samples were investigated by synchrotron-based X-ray microtomography (SR-µCT) after staining the sample with Osmium-tetroxide (OsO4) vapor. We utilized the monochromatic X-ray beam to locate osmium

33 CFR 330.5 - Issuing, modifying, suspending, or revoking nationwide permits and authorizations.

Science.gov (United States)

2010-07-01

...; progress inspections of individual activities occurring under an NWP; cumulative adverse environmental..., the extent to which asserting discretionary authority would adversely affect plans, investments, and... matter. After completion of the meeting (or within a reasonable period of time after suspending the...

Effect of organic matter properties, clay mineral type and thermal maturity on gas adsorption in organic-rich shale systems

Science.gov (United States)

Zhang, Tongwei; Ellis, Geoffrey S.; Ruppel, Stephen C.; Milliken, Kitty; Lewan, Mike; Sun, Xun; Baez, Luis; Beeney, Ken; Sonnenberg, Steve

2013-01-01

A series of CH4 adsorption experiments on natural organic-rich shales, isolated kerogen, clay-rich rocks, and artificially matured Woodford Shale samples were conducted under dry conditions. Our results indicate that physisorption is a dominant process for CH4 sorption, both on organic-rich shales and clay minerals. The Brunauer–Emmett–Teller (BET) surface area of the investigated samples is linearly correlated with the CH4 sorption capacity in both organic-rich shales and clay-rich rocks. The presence of organic matter is a primary control on gas adsorption in shale-gas systems, and the gas-sorption capacity is determined by total organic carbon (TOC) content, organic-matter type, and thermal maturity. A large number of nanopores, in the 2–50 nm size range, were created during organic-matter thermal decomposition, and they significantly contributed to the surface area. Consequently, methane-sorption capacity increases with increasing thermal maturity due to the presence of nanopores produced during organic-matter decomposition. Furthermore, CH4 sorption on clay minerals is mainly controlled by the type of clay mineral present. In terms of relative CH4 sorption capacity: montmorillonite ≫ illite – smectite mixed layer > kaolinite > chlorite > illite. The effect of rock properties (organic matter content, type, maturity, and clay minerals) on CH4 adsorption can be quantified with the heat of adsorption and the standard entropy, which are determined from adsorption isotherms at different temperatures. For clay-mineral rich rocks, the heat of adsorption (q) ranges from 9.4 to 16.6 kJ/mol. These values are considerably smaller than those for CH4 adsorption on kerogen (21.9–28 kJ/mol) and organic-rich shales (15.1–18.4 kJ/mol). The standard entropy (Δs°) ranges from -64.8 to -79.5 J/mol/K for clay minerals, -68.1 to -111.3 J/mol/K for kerogen, and -76.0 to -84.6 J/mol/K for organic-rich shales. The affinity of CH4 molecules for sorption on organic matter

Evaluation of the production, composition and aluminum and iron complexation of algogenic organic matter

Czech Academy of Sciences Publication Activity Database

Pivokonský, Martin; Klouček, Ondřej; Pivokonská, Lenka

2006-01-01

Roč. 40, č. 16 (2006), s. 3045-3052 ISSN 0043-1354 R&D Projects: GA AV ČR KJB200600501 Institutional research plan: CEZ:AV0Z20600510 Keywords : affinity chromatography * algogenic organic matter * aluminum and iron coagulants * extracellular organic matter * molecular weight fractionation * intracellular organic matter Subject RIV: BK - Fluid Dynamics Impact factor: 2.459, year: 2006

Modeling the vertical soil organic matter profile using Bayesian parameter estimation

Directory of Open Access Journals (Sweden)

M. C. Braakhekke

2013-01-01

Full Text Available The vertical distribution of soil organic matter (SOM in the profile may constitute an important factor for soil carbon cycling. However, the formation of the SOM profile is currently poorly understood due to equifinality, caused by the entanglement of several processes: input from roots, mixing due to bioturbation, and organic matter leaching. In this study we quantified the contribution of these three processes using Bayesian parameter estimation for the mechanistic SOM profile model SOMPROF. Based on organic carbon measurements, 13 parameters related to decomposition and transport of organic matter were estimated for two temperate forest soils: an Arenosol with a mor humus form (Loobos, the Netherlands, and a Cambisol with mull-type humus (Hainich, Germany. Furthermore, the use of the radioisotope ²¹⁰Pb_ex as tracer for vertical SOM transport was studied. For Loobos, the calibration results demonstrate the importance of organic matter transport with the liquid phase for shaping the vertical SOM profile, while the effects of bioturbation are generally negligible. These results are in good agreement with expectations given in situ conditions. For Hainich, the calibration offered three distinct explanations for the observations (three modes in the posterior distribution. With the addition of ²¹⁰Pb_ex data and prior knowledge, as well as additional information about in situ conditions, we were able to identify the most likely explanation, which indicated that root litter input is a dominant process for the SOM profile. For both sites the organic matter appears to comprise mainly adsorbed but potentially leachable material, pointing to the importance of organo-mineral interactions. Furthermore, organic matter in the mineral soil appears to be mainly derived from root litter, supporting previous studies that highlighted the importance of root input for soil carbon sequestration. The ²¹⁰

Sorptive stabilization of organic matter by amorphous Al hydroxide

NARCIS (Netherlands)

Schneider, M.P.W.; Scheel, T.; Mikutta, R.; van Hees, P.; Kaiser, K.; Kalbitz, K.

2010-01-01

Amorphous Al hydroxides (am-Al(OH)(3)) strongly sorb and by this means likely protect dissolved organic matter (OM) against microbial decay in soils. We carried out batch sorption experiments (pH 4.5; 40 mg organic C L-1) with OM extracted from organic horizons under a Norway spruce and a European

Validation of a field filtration technique for characterization of suspended particulate matter from freshwater. Part II. Minor, trace and ultra trace elements

International Nuclear Information System (INIS)

Odman, Fredrik; Ruth, Thomas; Rodushkin, Ilia; Ponter, Christer

2006-01-01

A field filtration method for the concentration and separation of suspended particulate matter (SPM) from freshwater systems and the subsequent determination of minor, trace and ultra trace elements (As, Ba, Be, Cd, Co, Cr, Cs, Cu, Ga, Hf, Mo, Nb, Ni, Pb, Rb, Sb, Sc, Sn, Sr, Ta, Th, Tl, U, V, W, Zn and Zr) is validated with respect to detection limits, precision and bias. The validation comprises the whole procedure including filtration, sample digestion and instrumental analysis. The method includes two digestion procedures (microwave acid digestion and alkali fusion) in combination with inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma quadrupole mass spectrometry (ICP-QMS). Total concentrations of these 27 trace and minor elements have been determined in suspended particulate matter (SPM) from lake and river water with low levels of suspended solids ( -1 DW), and a wide range of element concentrations. The precision of the method including filtration, digestion and instrumental determination ranges between 8% and 18% RSD for most elements on a dry weight basis. Higher recovery after acid digestion is found for some elements, probably because of volatilization or retention losses in the fusion procedure. Other elements show higher recovery after fusion, which is explained by more efficient decomposition of refractory mineral phases relative to the non-total acid digestion. Non-detectable concentrations of some elements are reported due to small differences between blank filter levels and the amounts of elements present on the filters after sampling. The method limits of detection range between 0.7 ng and 2.65 μg, as estimated from the blank filter samples. These detection limits are 10-550 times higher compared to the corresponding instrumental limits of detection. The accuracy and bias of the overall analytical procedure was assessed from replicate analysis of certified reference materials. A critical evaluation of

Distinctive effects of allochthonous and autochthonous organic matter on CDOM spectra in a tropical lake

Directory of Open Access Journals (Sweden)

L. P. M. Brandão

2018-05-01

Full Text Available Despite the increasing understanding about differences in carbon cycling between temperate and tropical freshwater systems, our knowledge on the importance of organic matter (OM pools on light absorption properties in tropical lakes is very scarce. We performed a factorial mesocosm experiment in a tropical lake (Minas Gerais, Brazil to evaluate the effects of increased concentrations of allochthonous and autochthonous OM, and differences in light availability on the light absorption characteristics of chromophoric dissolved organic matter (CDOM. Autochthonous OM deriving from phytoplankton ( ∼  Chl a was stimulated by addition of nutrients, while OM from degradation of terrestrial leaves increased allochthonous OM, and neutral shading was used to manipulate light availability. Effects of the additions and shading on DOC, Chl a, nutrients, total suspended solid concentrations (TSM and spectral CDOM absorption were monitored every 3 days. CDOM quality was characterized by spectral indices (S250–450, S275–295, S350–450, SR and SUVA254. Effects of carbon sources and shading on the spectral CDOM absorption was investigated through principal component (PCA and redundancy (RDA analyses. The two different OM sources affected CDOM quality very differently and shading had minor effects on OM levels, but significant effects on OM quality, especially in combination with nutrient additions. Spectral indices (S250–450 and SR were mostly affected by allochthonous OM addition. The PCA showed that enrichment by allochthonous carbon had a strong effect on the CDOM spectra in the range between 300 and 400 nm, while the increase in autochthonous carbon increased absorption at wavelengths below 350 nm. Our study shows that small inputs of allochthonous OM can have large effects on the spectral light absorption compared to large production of autochthonous OM, with important implications for carbon cycling in tropical lakes.

Annual variability in light absorption by particles and colored dissolved organic matter in the Crimean coastal waters (the Black Sea)

Science.gov (United States)

Churilova, T.; Moiseeva, N.; Efimova, T.; Suslin, V.; Krivenko, O.; Zemlianskaia, E.

2017-11-01

Bio-optical studies were carried out in coastal waters around the Crimea peninsula in different seasons 2016. It was shown that variability of chlorophyll a concentration (Chl-a), light absorption by suspended particles (ap(λ)), phytoplankton pigments (aph(λ)), non-algal particles (aNAP(λ)) and by colored dissolved organic matter (aCDOM(λ)) in the Crimea coastal water was high ( order of magnitudes) in all seasons 2016. Relationships between ap(440), aph(440) and Chl-a were obtained and their seasonal differences were analyzed. Spectral distribution of aNAP(λ) and aCDOM(λ) were parameterized. Seasonality in aCDOM(λ) parameterization was revealed, but - in aNAP(λ) parameterization was not revealed. The budget of light absorption by aph(λ), aNAP(λ) i aCDOM(λ) at 440 nm was assessed and its seasonal dynamics was analyzed.

Lability of Secondary Organic Particulate Matter

Energy Technology Data Exchange (ETDEWEB)

Liu, Pengfei; Li, Yong Jie; Wang, Yan; Giles, Mary K.; Zaveri, Rahul A.; Bertram, Allan K.; Martin, Scot T.

2016-10-24

Accurate simulations of the consenctrations of atmospheric organic particulate matter (PM) are needed for predicting energy flow in the Earth’s climate system. In the past, simulations of organic PM widely assume equilibrium partitioning of semivolatile organic compounds (SVOCs) between the PM and surrounding vapor. Herein, we test this assumption by measuring evaporation rates and associated vapor mass concentration of organic films representative of atmospheric PM. For films representing anthropogenic PM, evaporation rates and vapor mass concentrations increased above a threshold relative humidity (RH), indicating equilibrium partitioning above a transition RH but not below. In contrast for films representing biogenic PM, no threshold was observed, indicating equilibrium partitioning at all RHs. The results suggest that the mass lability of atmospheric organic PM can differ in consequential ways among Earth’s natural biomes, polluted regions, and regions of land-use change, and these differences need to be considered when simulating atmospheric organic PM.

Changes in different organic matter fractions during conventional treatment and advanced treatment

Institute of Scientific and Technical Information of China (English)

Chao Chen; Xiaojian Zhang; Lingxia Zhu; Wenjie He; Hongda Han

2011-01-01

XAD-8 resin isolation of organic matter in water was used to divide organic matter into the hydrophobic and hydrophilic fractions.A pilot plant was used to investigate the change in both fractions during conventional and advanced treatment processes.The treatment of hydrophobic organics (HPO), rather than hydrophilic organicas (HPI), should carry greater emphasis due to HPO's higher trihalomethane formation potential (THMFP) and haloacetic acid formation potential (HAAFP).The removal of hydrophobic matter and its transmission into hydrophilic matter reduced ultimate DBP yield during the disinfection process.The results showed that sand filtration, ozonation, and biological activated carbon (BAC) filtration had distinct influences on the removal of both organic fractions.Additionally, the combination of processes changed the organic fraction proportions present during treatment.The use of ozonation and BAC maximized organic matter removal efficiency, especially for the hydrophobic fraction.In sum, the combination of pre-ozonation,conventional treatment, and O3-BAC removed 48％ of dissolved organic carbon (DOC), 60％ of HPO, 30％ of HPI, 63％ of THMFP,and 85％ of HAAFP.The use of conventional treatment and O3-BAC without pre-ozonation had a comparable performance, removing 51％ of DOC, 56％ of HPO, 45％ of HPI, 61％ of THMFP, and 72％ of HAAFP.The effectiveness of this analysis method indicated that resin isolation and fractionation should be standardized as an applicable test to help assess water treatment process efficiency.

Organic matter degradation drives benthic cyanobacterial mat abundance on Caribbean coral reefs.

Science.gov (United States)

Brocke, Hannah J; Polerecky, Lubos; de Beer, Dirk; Weber, Miriam; Claudet, Joachim; Nugues, Maggy M

2015-01-01

Benthic cyanobacterial mats (BCMs) are impacting coral reefs worldwide. However, the factors and mechanisms driving their proliferation are unclear. We conducted a multi-year survey around the Caribbean island of Curaçao, which revealed highest BCM abundance on sheltered reefs close to urbanised areas. Reefs with high BCM abundance were also characterised by high benthic cover of macroalgae and low cover of corals. Nutrient concentrations in the water-column were consistently low, but markedly increased just above substrata (both sandy and hard) covered with BCMs. This was true for sites with both high and low BCM coverage, suggesting that BCM growth is stimulated by a localised, substrate-linked release of nutrients from the microbial degradation of organic matter. This hypothesis was supported by a higher organic content in sediments on reefs with high BCM coverage, and by an in situ experiment which showed that BCMs grew within days on sediments enriched with organic matter (Spirulina). We propose that nutrient runoff from urbanised areas stimulates phototrophic blooms and enhances organic matter concentrations on the reef. This organic matter is transported by currents and settles on the seabed at sites with low hydrodynamics. Subsequently, nutrients released from the organic matter degradation fuel the growth of BCMs. Improved management of nutrients generated on land should lower organic loading of sediments and other benthos (e.g. turf and macroalgae) to reduce BCM proliferation on coral reefs.

Organochlorine pesticides in surface sediments and suspended particulate matters from the Yangtze estuary, China

Energy Technology Data Exchange (ETDEWEB)

Liu Min [Department of Geography, Key Laboratory of Geographical Information Sciences of the State Ministry of Education, East China Normal University, Shanghai 200062 (China)], E-mail: mliu@geo.ecnu.edu.cn; Cheng Shubo; Ou Dongni [Department of Geography, Key Laboratory of Geographical Information Sciences of the State Ministry of Education, East China Normal University, Shanghai 200062 (China); Yang Yi [Vienna University, Department of Environmental Geoscience (Austria); Liu Hualin [Department of Geography, Key Laboratory of Geographical Information Sciences of the State Ministry of Education, East China Normal University, Shanghai 200062 (China); Hou Lijun [State Key Laboratory of Estuarine and Coastal Research, East China Normal University, Shanghai 200062 (China); Gao Lei; Xu Shiyuan [Department of Geography, Key Laboratory of Geographical Information Sciences of the State Ministry of Education, East China Normal University, Shanghai 200062 (China)

2008-11-15

Total HCHs' and total DDTs' levels in surface sediments (SS) ranged from 0.5 to 17.5 ng g{sup -1} and from 0.9 to 33.1 ng g{sup -1}, averaged 6.0 and 8.2 ng g{sup -1}, respectively. Total HCHs' and total DDTs' levels in suspended particulate matters (SPM) varied from 6.2 to 14.8 ng g{sup -1} with a mean value of 12.3 ng g{sup -1} and were from 3.4 to 25.7 ng g{sup -1} with an average of 16.4 ng g{sup -1}, respectively. Lindane is the main HCHs' source and continuing use in the Yangtze Delta areas of 'pure' {gamma}-HCH (lindane) rather than technical HCH (a mix of largely {alpha}- and some {gamma}-HCH). DDTs in SS are mainly accumulated in history. However, high DDT fractions in SPM are indicators of new input of typical dicofol type DDT from 2002 to 2004. It can be seen that most samples from the Yangtze estuary were in ranges where adverse biological effects are expected, either occasionally or frequently. - SPM, more polluted than SS, had similar contaminant composition. New input of lindane and typical dicofol type DDT were found and Yangtze estuary had been affected adversely.

Holocene provenance shift of suspended particulate matter in the Amazon River basin

Science.gov (United States)

Höppner, Natalie; Lucassen, Friedrich; Chiessi, Cristiano M.; Sawakuchi, André O.; Kasemann, Simone A.

2018-06-01

The strontium (Sr), neodymium (Nd) and lead (Pb) isotope signatures of suspended particulate matter (SPM) in rivers reflect the radiogenic isotope signatures of the rivers' drainage basin. These signatures are not significantly affected by weathering, transport or depositional cycles, but document the sedimentary contributions of the respective sources. We report new Sr, Nd and Pb isotope ratios and element concentrations of modern SPM from the Brazilian Amazon River basin and document the past evolution of the basin by analyzing radiogenic isotopes of a marine sediment core from the slope off French Guiana archiving the last 40 kyr of Amazon River SPM, and the Holocene section of sediment cores raised between the Amazon River mouth and the slope off French Guiana. The composition of modern SPM confirms two main source areas, the Andes and the cratonic Shield. In the marine sediment core notable changes occurred during the second phase of Heinrich Stadial 1 (i.e. increased proportion of Shield rivers SPM) and during the last deglaciation (i.e. increased proportion of Madeira River SPM) together with elsewhere constant source contributions. Furthermore, we report a prominent offset in Sr and Nd isotopic composition between the average core value (εNd: -11.7 ± 0.9 (2SD), 87Sr/86Sr: 0.7229 ± 0.0016 (2SD)) and the average modern Amazon River SPM signal (εNd: -10.5 ± 0.5 (2SD), 87Sr/86Sr: 0.7213 ± 0.0036 (2SD)). We suggest that a permanent change in the Amazon River basin sediment supply during the late Holocene to a more Andean dominated SPM was responsible for the offset.

The impact of vegetation on sedimentary organic matter composition and PAH desorption

Energy Technology Data Exchange (ETDEWEB)

Nichols, Elizabeth Guthrie [North Carolina State University, Department of Forestry and Environmental Resources, 2800 Faucette Drive, Raleigh, NC 27695 (United States)], E-mail: elizabeth_nichols@ncsu.edu; Gregory, Samuel T.; Musella, Jennifer S. [North Carolina State University, Department of Forestry and Environmental Resources, 2800 Faucette Drive, Raleigh, NC 27695 (United States)

2008-12-15

Relationships between sedimentary organic matter (SOM) composition and PAH desorption behavior were determined for vegetated and non-vegetated refinery distillate waste sediments. Sediments were fractionated into size, density, and humin fractions and analyzed for their organic matter content. Bulk sediment and humin fractions differed more in organic matter composition than size/density fractions. Vegetated humin and bulk sediments contained more polar organic carbon, black carbon, and modern (plant) carbon than non-vegetated sediment fractions. Desorption kinetics of phenanthrene, pyrene, chrysene, and C{sub 3}-phenanthrene/anthracenes from humin and bulk sediments were investigated using Tenax beads and a two-compartment, first-order kinetic model. PAH desorption from distillate waste sediments appeared to be controlled by the slow desorbing fractions of sediment; rate constants were similar to literature values for k{sub slow} and k{sub veryslow}. After several decades of plant colonization and growth (Phragmites australis), vegetated sediment fractions more extensively desorbed PAHs and had faster desorption kinetics than non-vegetated sediment fractions. - Plants alter sediment organic matter composition and PAH desorption behavior.

The impact of vegetation on sedimentary organic matter composition and PAH desorption

International Nuclear Information System (INIS)

Nichols, Elizabeth Guthrie; Gregory, Samuel T.; Musella, Jennifer S.

2008-01-01

Relationships between sedimentary organic matter (SOM) composition and PAH desorption behavior were determined for vegetated and non-vegetated refinery distillate waste sediments. Sediments were fractionated into size, density, and humin fractions and analyzed for their organic matter content. Bulk sediment and humin fractions differed more in organic matter composition than size/density fractions. Vegetated humin and bulk sediments contained more polar organic carbon, black carbon, and modern (plant) carbon than non-vegetated sediment fractions. Desorption kinetics of phenanthrene, pyrene, chrysene, and C 3 -phenanthrene/anthracenes from humin and bulk sediments were investigated using Tenax beads and a two-compartment, first-order kinetic model. PAH desorption from distillate waste sediments appeared to be controlled by the slow desorbing fractions of sediment; rate constants were similar to literature values for k slow and k veryslow . After several decades of plant colonization and growth (Phragmites australis), vegetated sediment fractions more extensively desorbed PAHs and had faster desorption kinetics than non-vegetated sediment fractions. - Plants alter sediment organic matter composition and PAH desorption behavior

Soil Organic Matter and Soil Productivity: Searching for the Missing Link

Science.gov (United States)

Felipe G. Sanchez

1998-01-01

Soil-organic matter (SOM) is a complex array of components including soil fauna and flora at different stages of decomposition (Berg et al., 1982). Its concentration in soils can vary from 0.5% in mineral soils to almost 100% in peat soils (Brady, 1974). Organic matter (OM) in the surface mineral soil is considered a major determinant of forest ecosystem productivity...

Reconstruction of MODIS total suspended matter time series maps by DINEOF and validation with autonomous platform data

Science.gov (United States)

Nechad, Bouchra; Alvera-Azcaràte, Aida; Ruddick, Kevin; Greenwood, Naomi

2011-08-01

In situ measurements of total suspended matter (TSM) over the period 2003-2006, collected with two autonomous platforms from the Centre for Environment, Fisheries and Aquatic Sciences (Cefas) measuring the optical backscatter (OBS) in the southern North Sea, are used to assess the accuracy of TSM time series extracted from satellite data. Since there are gaps in the remote sensing (RS) data, due mainly to cloud cover, the Data Interpolating Empirical Orthogonal Functions (DINEOF) is used to fill in the TSM time series and build a continuous daily "recoloured" dataset. The RS datasets consist of TSM maps derived from MODIS imagery using the bio-optical model of Nechad et al. (Rem Sens Environ 114: 854-866, 2010). In this study, the DINEOF time series are compared to the in situ OBS measured in moderately to very turbid waters respectively in West Gabbard and Warp Anchorage, in the southern North Sea. The discrepancies between instantaneous RS, DINEOF-filled RS data and Cefas data are analysed in terms of TSM algorithm uncertainties, space-time variability and DINEOF reconstruction uncertainty.

Fluorescence quantum yields of natural organic matter and organic compounds: Implications for the fluorescence-based interpretation of organic matter composition

DEFF Research Database (Denmark)

Wünsch, Urban; Murphy, Kathleen R.; Stedmon, Colin

2015-01-01

to more than 200 modeled spectra (PARAFAC components) in the OpenFluor database. Apparent matches, based on spectral similarity, were subsequently evaluated using molar fluorescence and absorbance. Five organic compounds were potential matches with PARAFAC components from 16 studies; however, the ability......Absorbance and fluorescence spectroscopy are economical tools for tracing the supply, turnover and fate of dissolved organic matter (DOM). The colored and fluorescent fractions of DOM (CDOM and FDOM, respectively) are linked by the apparent fluorescence quantum yield (AQY) of DOM, which reflects...... the likelihood that chromophores emit fluorescence after absorbing light. Compared to the number of studies investigating CDOM and FDOM, few studies have systematically investigated AQY spectra for DOM, and linked them to fluorescence quantum yields (Φ) of organic compounds. To offer a standardized approach...

The Effect of paper mill waste and sewage sludge amendments on soil organic matter

Science.gov (United States)

Méndez, Ana; Barriga, Sandra; Guerrero, Francisca; Gascó, Gabriel

2013-04-01

In general, Mediterranean soils have low organic matter content, due to the climate characteristics of this region and inadequate land management. Traditionally, organic wastes such as manure are used as amendment in order to improve the soil quality, increasing soil fertility by the accumulation of nitrogen, phosphorus and other plant nutrients in the soil. In the last decade, other anthropogenic organic wastes such as sewage sludge or paper waste materials have been studied as soil amendments to improve physical, chemical and biological properties of soils. The objective of the present work was to study the influence of waste from a paper mill and sewage sludge amendments on soil organic matter. For this reason, soil organic matter evolution was studied using thermogravimetric analysis (TGA), the derivative (dTG) and differential thermal analysis (DTA). Thermal analytical techniques have the advantage of using full samples without pre-treatments and have been extensively used to study the evolution of organic matter in soils, to evaluate composting process or to study the evolution of organic matter of growing media.

Effect of organic matter amendment, arsenic amendment and water management regime on rice grain arsenic species

International Nuclear Information System (INIS)

Norton, Gareth J.; Adomako, Eureka E.; Deacon, Claire M.; Carey, Anne-Marie; Price, Adam H.; Meharg, Andrew A.

2013-01-01

Arsenic accumulation in rice grain has been identified as a major problem in some regions of Asia. A study was conducted to investigate the effect of increased organic matter in the soil on the release of arsenic into soil pore water and accumulation of arsenic species within rice grain. It was observed that high concentrations of soil arsenic and organic matter caused a reduction in plant growth and delayed flowering time. Total grain arsenic accumulation was higher in the plants grown in high soil arsenic in combination with high organic matter, with an increase in the percentage of organic arsenic species observed. The results indicate that the application of organic matter should be done with caution in paddy soils which have high soil arsenic, as this may lead to an increase in accumulation of arsenic within rice grains. Results also confirm that flooding conditions substantially increase grain arsenic. -- Highlights: ► High soil arsenic and organic matter caused a reduction in plant growth. ► A delayed flowering time was observed in high arsenic and organic matter soil. ► Total grain arsenic increased in high arsenic and organic matter soil. ► Percentage organic arsenic in the grain altered in arsenic and organic matter soil. -- The addition of high amounts of organic matter to soils led to an increase in total rice grain arsenic, as well as alteration in the percentage arsenic species in the rice grains

Characterization of Soil Organic Matter in Peat Soil with Different Humification Levels using FTIR

Science.gov (United States)

Teong, I. T.; Felix, N. L. L.; Mohd, S.; Sulaeman, A.

2016-07-01

Peat soil is defined as an accumulation of the debris and vegetative under the water logging condition. Soil organic matter of peat soil was affected by the environmental, weather, types of vegetative. Peat soil was normally classified based on its level of humification. Humification can be defined as the transformation of numerous group of substances (proteins, carbohydrates, lipids, etc.) and individual molecules present in living organic matter into group of substances with similar properties (humic substances). During the peat transformation process, content of soil organic matter also will change. Hence, that is important to determine out the types of the organic compound. FTIR (Fourier Transform Infrared) is a machine which is used to differential soil organic matter by using infrared. Infrared is a types of low energy which can determine the organic minerals. Hence, FTIR can be suitable as an indicator on its level of humification. The main objective of this study is to identify an optimized method to characterization of the soil organic content in different level of humification. The case study areas which had been chosen for this study are Parit Sulong, Batu Pahat and UCTS, Sibu. Peat soil samples were taken by every 0.5 m depth until it reached the clay layer. However, the soil organic matter in different humification levels is not significant. FTIR is an indicator which is used to determine the types of soil, but it is unable to differentiate the soil organic matter in peat soil FTIR can determine different types of the soil based on different wave length. Generally, soil organic matter was found that it is not significant to the level of humification.

Soil architecture and distribution of organic matter

NARCIS (Netherlands)

Kooistra, M.J.; Noordwijk, van M.

1996-01-01

The biological component of soil structure varies greatly in quality and quantity, occurs on different scales, and varies throughout the year. It is far less predictable than the physical part and human impact. The occurrence and distribution of organic matter depends on several processes, related

A Robust Analysis Method For Δ13c Signal Of Bulk Organic Matter In Speleothems

Science.gov (United States)

Bian, F.; Blyth, A. J.; Smith, C.; Baker, A.

2017-12-01

Speleothems preserve organic matter that is derived from both the surface soil and cave environments. This organic matter can be used to understand paleoclimate and paleoenvironments. However, a stable and quick micro-analysis method to measure the δ13C signals from speleothem organic matter separate from the total δ13C remains absent. And speleothem organic geochemistry is still relatively unexplored compared to inorganic geochemistry. In this research, for the organic matter analysis, bulk homogeneous power samples were obtained from one large stalagmite. These were dissolved by phosphoric acid to produce the aqueous solution. Then, the processed solution was degassed through a rotational vacuum concentrator. A liquid chromatograph was coupled to IRMS to control the oxidization and the measurement of analytes. This method is demonstrated to be robust for the analysis of speleothem d13C organic matter analysis under different preparation and instrumental settings, with the low standard deviation ( 0.2‰), and low sample consumption (<25 mg). Considering the complexity of cave environments, this method will be useful in further investigations the δ13C of entrapped organic matter and environmental controls in other climatic and ecological contexts, including the determination of whether vegetation or soil microbial activity is the dominant control on speleothem d13C of organic matter.

Suspended particulate studies over the Madeira Abyssal Plain

International Nuclear Information System (INIS)

Simpson, W.R.

1987-01-01

Various aspects relating to suspended matter over the Madeira Abyssal Plain are discussed. Special attention is paid to the nepheloid layer including resuspension and transport processes; time variabilities in particle concentrations and fluxes; particle morphology, microbiology and chemical composition; phase association of metals. Also, tentative predictions of the behaviour of some radionuclides are made based on theory and data on rare earth elements. Instrumentation developed for the project is detailed - the deep water particle sampler. (author)

Arsenic speciation in water, suspended particles, and coastal organisms from the Taehwa River Estuary of South Korea

International Nuclear Information System (INIS)

Hong, Seongjin; Kwon, Hye-Ok; Choi, Sung-Deuk; Lee, Jung-Suk; Khim, Jong Seong

2016-01-01

Water, suspended particulate matter (SPM), and biota samples were collected from the Taehwa River Estuary to determine the distributions, partitioning, and bioaccumulation of arsenicals. Six forms of As were quantitated by the use of HPLC-ICP/MS. As was found mainly near urban and industrial areas, and inorganic As V was the predominant As form in both water and SPM. Particulate arsenicals were found at the greatest concentrations in coarse particles (> 180 μm), followed by medium (30–180 μm) and fine (0.45–30 μm) particles, in freshwater. Arsenical concentrations were similar across the three particle fractions in saltwater. Field-based distribution coefficient (K d ) values for As depended strongly on SPM, with a less robust dependence on salinity. Concentrations of As were greater in macroalgae than in marine animals, such as fishes, bivalves, crabs, shrimps, and gastropods. Overall, the results of the present study provide useful information on the behaviors and fate of arsenicals in an estuarine environment. - Highlights: •Concentrations of As were greater in industrial and urban areas than in suburban area. •The predominant form of As in water and suspended particles was inorganic As V . •Particle-size distributions of arsenicals differed between freshwater and saltwater. •The K d values for As depended strongly on the presence of SPMs along the estuary. •Greater concentrations of arsenicals were found in macroalgae than in marine animals.

Characterization of Natural Organic Matter by FeCl3 Coagulation

Science.gov (United States)

Cahyonugroho, O. H.; Hidayah, E. N.

2018-01-01

Natural organic matter (NOM) is heterogenous mixture of organic compounds that enter the water from various decomposition and metabolic reactions, including animal, plant, domestic and industrial wastes. NOM refers to group of carbon-based compounds that are found in surface water and ground water. The aim of the study is to assess organic matter characteristics in Jagir River as drinking water source and to characterize the organic components that could be removed during coagulation. Coagulation is the common water treatment process can be used to remove NOM with FeCl3 coagulant in various dosage. NOM surrogates, including total organic carbon (TOC), ultraviolet absorbance at 254 nm (UV254) and specific UV absorbance (SUVA) were chosen to assess the organic removal. Results of jar test experiments showed that NOM can be removed about 40% of NOM surrogates with 200 mg/L FeCl3. About 60% removal of total organic fraction, which is mainly humic substances, as detected by size exclusion chromatography (SEC).

ORGANIC CARBON AND TOTAL NITROGEN IN THE DENSIMETRIC FRACTIONS OF ORGANIC MATTER UNDER DIFFERENT SOIL MANAGEMEN

Directory of Open Access Journals (Sweden)

MARCELO RIBEIRO VILELA PRADO

2016-01-01

Full Text Available The evaluation of land use and management by the measurement of soil organic matter and its fractions has gained attention since it helps in the understanding of the dynamics of their contribution to soil productivity, especially in tropical environments. This study was conducted in the municipality of Colorado do Oeste, state of Rondônia, Brazil and its aim was to determinethe quantity of organic carbon and total nitrogen in the light and heavy fractions of organic matter in the surface layers of a typic hapludalf under different land use systems: Native Forest: open evergreen forest, reference environment; Agroforestry System 1: teak (Tectona grandis LF and kudzu (Pueraria montana; Agroforestry System 2: coffee (Coffea canephora, marandu palisade grass (Brachiaria brizantha cv. Marandu, “pinho cuiabano” (Parkia multijuga, teak and kudzu.; Agroforestry System 3: teak and cocoa (Theobroma cacao; Silvopasture System: teak, cocoa and marandu palisade grass; and Extensive Grazing System: marandu palisade grass. The experimental design was a randomized block in split-split plots (use systems versus soil layers of 0-0.05 and 0.05-0.10 m with three replications. The results showed that relative to Native Forest, the Agroforestry System 2 had equal- and greater amounts of organic carbon and total nitrogen respectively (light and heavy fractions in the soil organic matter, with the light fraction being responsible for storage of approximately 45% and 70% of the organic carbon and total nitrogen, respectively. Therefore, the light densimetric fraction proved to be useful in the early identification of the general decline of the soil organic matter in the land use systems evaluated.

Organic matter sources, fluxes and greenhouse gas exchange in the Oubangui River (Congo River basin)

Science.gov (United States)

Bouillon, S.; Yambélé, A.; Spencer, R. G. M.; Gillikin, D. P.; Hernes, P. J.; Six, J.; Merckx, R.; Borges, A. V.

2012-06-01

The Oubangui is a major tributary of the Congo River, draining an area of ~500 000 km2 mainly consisting of wooded savannahs. Here, we report results of a one year long, 2-weekly sampling campaign in Bangui (Central African Republic) since March 2010 for a suite of physico-chemical and biogeochemical characteristics, including total suspended matter (TSM), bulk concentration and stable isotope composition of particulate organic carbon (POC and δ13CPOC), particulate nitrogen (PN and δ15NPN), dissolved organic carbon (DOC and δ13CDOC), dissolved inorganic carbon (DIC and δ13CDIC), dissolved greenhouse gases (CO2, CH4 and N2O), and dissolved lignin composition. δ13C signatures of both POC and DOC showed strong seasonal variations (-30.6 to -25.8‰, and -31.8 to -27.1‰, respectively), but their different timing indicates that the origins of POC and DOC may vary strongly over the hydrograph and are largely uncoupled, differing up to 6‰ in δ13C signatures. Dissolved lignin characteristics (carbon-normalised yields, cinnamyl:vanillyl phenol ratios, and vanillic acid to vanillin ratios) showed marked differences between high and low discharge conditions, consistent with major seasonal variations in the sources of dissolved organic matter. We observed a strong seasonality in pCO2, ranging between 470 ± 203 ppm for Q production may be high enough to dominate the particulate organic carbon pool, and lower pCO2 values to near equilibrium values during low discharge conditions. The total annual flux of TSM, POC, PN, DOC and DIC are 2.33 Tg yr-1, 0.14 Tg C yr-1, 0.014 Tg N yr-1, 0.70 Tg C yr-1, and 0.49 Tg C yr-1, respectively. While our TSM and POC fluxes are similar to previous estimates for the Oubangui, DOC fluxes were ~30% higher and bicarbonate fluxes were ~35% lower than previous reports. DIC represented 58% of the total annual C flux, and under the assumptions that carbonate weathering represents 25% of the DIC flux and that CO2 from respiration drives

Microbial bioavailability regulates organic matter preservation in marine sediments

NARCIS (Netherlands)

Koho, K. A.; Nierop, K. G. J.; Moodley, L.; Middelburg, J. J.; Pozzato, L.; Soetaert, K.; van der Plicht, J.; Reichart, G-J.; Herndl, G.

2013-01-01

Burial of organic matter (OM) plays an important role in marine sediments, linking the short-term, biological carbon cycle with the long-term, geological subsurface cycle. It is well established that low-oxygen conditions promote organic carbon burial in marine sediments. However, the mechanism

Influence of organic matter on the solubility of ThO2 and geochemical modeling

International Nuclear Information System (INIS)

Liu Dejun; Luo Tian; Maes, N.; Bruggeman, C.

2014-01-01

Thorium (IV) is widely considered in laboratory experiments as a suitable chemical analogue for long-lived tetravalent actinides. Th (IV) is redox-insensitive, as an analogue for U (IV) to study the influence of natural organic matter on the solubility. The solubility of crystalline ThO 2 (cr) has been measured under geochemical conditions representative for the Boom Clay using Real Boom Clay Water containing organic matter to assess its influence on the ThO 2 (cr) solubility. For the purpose of comparison, Aldrich Humic Acid was also investigated. Solubility measurements of ThO 2 (cr) were approached from under-saturation in an anaerobic glove box with a controlled Ar0.4%CO 2 atmosphere. Th concentration is determined after 30000 MWCO, 300000 MWCO, and 0.45 μm filtration to distinguish solid (0.45 μm), larger colloids (300000 MWCO), and small dissolved species(30000 MWCO). X-ray diffraction was carried out to investigate the transformation of ThO 2 (cr) phase during the contact with Boom Clay Water. In Synthetic Boom Clay Water (without organic matter) the concentrations of Th (IV) are 5 × l0 -ll mol/L, 4 × lO -10 mol/L, and 8 × lO -8 mol/L after 30000 MWCO, 300000 MWCO, and 0. 45 μm filtration, respectively. It indicated the existence of inorganic colloids in solution. The increase of the total Th solution concentration with increasing organic matter concentration revealed a complexation-like interaction between Th and organic matter. All the experimental data could be modeled by Tipping humic ion-binding model VI using a combination of solubility calculations and complexation reactions between Th (IV) and organic matter functional groups. Similar to the investigation of Eu 3+ solubility, the affinity of organic matter for Th was higher for Aldrich humic acid compared to Boom Clay organic matter. However, Boom Clay organic matter with different size had the similar complexation affinity with Th (IV). (authors)

Significance of Isotopically Labile Organic Hydrogen in Thermal Maturation of Organic Matter

Energy Technology Data Exchange (ETDEWEB)

Arndt Schimmelmann; Maria Mastalerz

2010-03-30

Isotopically labile organic hydrogen in fossil fuels occupies chemical positions that participate in isotopic exchange and in chemical reactions during thermal maturation from kerogen to bitumen, oil and gas. Carbon-bound organic hydrogen is isotopically far less exchangeable than hydrogen bound to nitrogen, oxygen, or sulfur. We explore why organic hydrogen isotope ratios express a relationship with organic nitrogen isotope ratios in kerogen at low to moderate maturity. We develop and apply new techniques to utilize organic D/H ratios in organic matter fractions and on a molecular level as tools for exploration for fossil fuels and for paleoenvironmental research. The scope of our samples includes naturally and artificially matured substrates, such as coal, shale, oil and gas.

Optical properties of size fractions of suspended particulate matter in littoral waters of Québec

Directory of Open Access Journals (Sweden)

G. Mohammadpour

2017-11-01

Full Text Available Mass-specific absorption (ai∗(λ and scattering (bi∗(λ coefficients were derived for four size fractions (i =  0.2–0.4, 0.4–0.7, 0.7–10, and > 10 µm, λ = wavelength in nm of suspended particulate matter (SPM and with samples obtained from surface waters (i.e., 0–2 m depth of the Saint Lawrence Estuary and Saguenay Fjord (SLE-SF during June of 2013. For the visible–near-infrared spectral range (i.e., λ = 400–710 nm, mass-specific absorption coefficients of total SPM (i.e., particulates > 0.2 µm (hereafter aSPM∗ had low values (e.g., < 0.01 m2 g−1 at λ = 440 nm in areas of the lower estuary dominated by particle assemblages with relatively large mean grain size and high particulate organic carbon and chlorophyll a per unit of mass of SPM. Conversely, largest aSPM∗ values (i.e., > 0.05 m2 g−1 at λ = 440 nm corresponded with locations of the upper estuary and SF where particulates were mineral-rich and/or their mean diameter was relatively small. The variability of two optical proxies (the spectral slope of particulate beam attenuation coefficient and the mass-specific particulate absorption coefficient, hereafter γ and Svis, respectively with respect to changes in particle size distribution (PSD and chemical composition was also examined. The slope of the PSD was correlated with bi∗(550 (Spearman rank correlation coefficient ρs up to 0.37 and ai∗(440 estimates (ρs up to 0.32 in a comparable way. Conversely, the contribution of particulate inorganic matter to total mass of SPM (FSPMPIM had a stronger correlation with ai∗ coefficients at a wavelength of 440 nm (ρs up to 0.50. The magnitude of γ was positively related to FSPMi or the contribution of size fraction i to the total mass of SPM (ρs up to 0.53 for i = 0.2–0.4 µm. Also, the relation between γ and FSPMPIM variability was secondary (ρs = −0.34, P > 0.05. Lastly, the magnitude

Mean residence time of soil organic matter associated with kaolinite and smectite

NARCIS (Netherlands)

Wattel-Koekkoek, E.J.W.; Buurman, P.; Plicht, van der J.; Wattel, J.T.; Breemen, van N.

2003-01-01

To gain insight into the effect of clay mineralogy on the turnover of organic matter, we analysed the C-14 activity of soil organic matter associated with clay in soils dominated by kaolinite and smectite in natural savanna systems in seven countries. Assuming that carbon inputs and outputs are in

Mean residence time of soil organic matter associated with kaolinite and smectite

NARCIS (Netherlands)

Wattel-Koekkoek, E.J.W.; Buurman, P.; Plicht, J. van der; Wattel, E.; Breemen, N. van

To gain insight into the effect of clay mineralogy on the turnover of organic matter, we analysed the C-14 activity of soil organic matter associated with clay in soils dominated by kaolinite and smectite in natural savanna systems in seven countries. Assuming that carbon inputs and outputs are in

Cosorption study of organic pollutants and dissolved organic matter in a soil.

Science.gov (United States)

Flores-Céspedes, F; Fernández-Pérez, M; Villafranca-Sánchez, M; González-Pradas, E

2006-08-01

In this study we have evaluated the effects of dissolved organic matter (DOM) on sorption of imidacloprid, 3,4-dichloroaniline (3,4-DCA) and 4-bromoaniline (4-BA) on a typical calcareous soil (Luvic Xerosol) from south-eastern Spain. Two different types of DOM were used, that is to say, dissolved natural organic matter extracts from a commercial peat (DNOM) and a high-purity tannic acid (TA) solution. The experiments were carried out in a 0.01 M CaCl2 aqueous medium at 25 degrees C. The results indicated that the presence of both DNOM and TA, over a concentration range of 15-100 mg L(-1), produced an increase in the amount of 3,4-DCA and 4-BA sorbed and a decrease in the amount of imidacloprid retained on the soil studied. A modified distribution coefficient, K(doc), has been proposed as a safer parameter for soil sorption predictions of organic pollutants and it could be of help to model the fate of these in the environment.

Dependence of 210Po activity on organic matter in the reverine environs of coastal Kerala

International Nuclear Information System (INIS)

Narayana, Y.; Venunathan, N.

2011-01-01

This paper deals with the distribution of 210 Po in the river bank soil samples of three major rivers namely Bharathapuzha, Periyar and Kallada river of Kerala. The dependence of 210 Po activity on organic matter content in the samples was also studied. The soil samples were collected and analyzed for 210 Po radionuclide using standard radiochemical analytical method. Activity of 210 Po increases with increase in organic matter content in samples. Along the Bharathapuzha river bank the 210 Po activity ranges from 2.96 to 12.48 Bq kg -1 with mean 5.62 Bq kg -1 . The organic matter percentage in the samples ranges from 0.4 to 2.8 and a good correlation with correlation coefficient 0.9 was found between activity and organic matter percentage. In the Periyar river environs 210 Po activity ranges from 3.47 to 13.39 Bq kg -1 with mean value 9.27 Bq kg -1 . Organic matter percentage in these samples ranges from 1.20 to 4.10 and the correlation coefficient between 210 Po activity and organic matter percentage was found to be 0.8 In the Kallada river bank soil samples 210 Po activity ranges from 4.46 to 6.45 Bq kg -1 . The organic matter percentage ranges from 1.4 to 3. The correlation coefficient between 210 Po activity and organic matter percentage in the samples was found to be 0.9. (author)

Influencing factors on δ(13C) of organic matter and carbonate in labke sediments on songnen plain

International Nuclear Information System (INIS)

Ou Wenjia; Zhang Chengjun

2009-01-01

Carbon isotopic compositions of organic matter and carbonate in surface sediments from lakes in Songnen Plain, northeast of China, were carried out.n-alkanes carbon distribution characteristics of the organic matter in lake sediments were also analyzed to identify the source of organic matter and sedimentary environment in these lakes. With the limnological characteristics of water and sediment, the influencing factors on isotopic composition in sedimentary organic matter and carbonate were discussed. The results showed that types of organic matter affected the carbon isotopic composition. 13 C of carbonate depleted by input of biologic organic matter and enriched by input of oil pollution. (authors)

Repeated application of organic waste affects soil organic matter composition

DEFF Research Database (Denmark)

Peltre, Clément; Gregorich, Edward G.; Bruun, Sander

2017-01-01

Land application of organic waste is an important alternative to landfilling and incineration because it helps restore soil fertility and has environmental and agronomic benefits. These benefits may be related to the biochemical composition of the waste, which can result in the accumulation...... of different types of carbon compounds in soil. The objective of this study was to identify and characterise changes in soil organic matter (SOM) composition after repeated applications of organic waste. Soil from the CRUCIAL field experiment in Denmark was sampled after 12 years of annual application...... that there was accumulation in soil of different C compounds for the different types of applied organic waste, which appeared to be related to the degree to which microbial activity was stimulated and the type of microbial communities applied with the wastes or associated with the decomposition of applied wastes...

Seafloor ecosystem functioning: the importance of organic matter priming

NARCIS (Netherlands)

Van Nugteren, P.; Moodley, L.; Brummer, G.J.; Heip, C.H.R.; Herman, P.M.J.; Middelburg, J.J.

2009-01-01

Organic matter (OM) remineralization may be considered a key function of the benthic compartment of marine ecosystems and in this study we investigated if the input of labile organic carbon alters mineralization of indigenous sediment OM (OM priming). Using 13C-enriched diatoms as labile tracer

Comprehensive characterization of atmospheric organic matter in Fresno, California fog water.

Science.gov (United States)

Herckes, Pierre; Leenheer, Jerry A; Collett, Jeffrey L

2007-01-15

Fogwater collected during winter in Fresno (CA) was characterized by isolating several distinct fractions and characterizing them by infrared and nuclear magnetic resonance (NMR) spectroscopy. More than 80% of the organic matter in the fogwater was recovered and characterized. The most abundant isolated fractions were those comprised of volatile acids (24% of isolated carbon) and hydrophilic acids plus neutrals (28%). Volatile acids, including formic and acetic acid, have been previously identified as among the most abundant individual species in fogwater. Recovered hydrophobic acids exhibited some properties similar to aquatic fulvic acids. An insoluble particulate organic matter fraction contained a substantial amount of biological material, while hydrophilic and transphilic fractions also contained material suggestive of biotic origin. Together, these fractions illustrate the important contribution biological sources make to organic matter in atmospheric fog droplets. The fogwater also was notable for containing a large amount of organic nitrogen present in a variety of species, including amines, nitrate esters, peptides, and nitroso compounds.

SOIL NITROGEN TRANSFORMATIONS AND ROLE OF LIGHT FRACTION ORGANIC MATTER IN FOREST SOILS

Science.gov (United States)

Depletion of soil organic matter through cultivation may alter substrate availability for microbes, altering the dynamic balance between nitrogen (N) immobilization and mineralization. Soil light fraction (LF) organic matter is an active pool that decreases upon cultivation, and...

Turnover of intra- and extra-aggregate organic matter at the silt-size scale

Science.gov (United States)

I. Virto; C. Moni; C. Swanston; C. Chenu

2010-01-01

Temperate silty soils are especially sensitive to organic matter losses associated to some agricultural management systems. Long-term preservation of organic C in these soils has been demonstrated to occur mainly in the silt- and clay-size fractions, although our knowledge about the mechanisms through which it happens remains unclear. Although organic matter in such...

The Physics of Life. Part I: The Animate Organism as an Active Condensed Matter Body

OpenAIRE

Kukuruznyak , Dmitry ,

2017-01-01

Nonequilibrium "active agents" establish bonds with each other and create a quickly evolving condensed state known as active matter. Recently, active matter composed of motile self-organizing biopolymers demonstrated a biotic-like motion similar to cytoplasmic streaming. It was suggested that the active matter could produce cells. However, active matter physics cannot yet define an " organism " and thus make a satisfactory connection to biology. This paper describes an organism made of active...

Effect of selective removal of organic matter and iron oxides on the ...

African Journals Online (AJOL)

The effect of selective removal of organic matter and amorphous and crystalline iron oxides on N2-BET specific surface areas of some soil clays was evaluated. Clay fractions from 10 kaolinitic tropical soils were successively treated to remove organic matter by oxidation with Na hypochlorite, amorphous Fe oxide with acid ...

pH dependence of steroid hormone-organic matter interactions at environmental concentrations

Energy Technology Data Exchange (ETDEWEB)

Neale, Peta A. [School of Engineering and Electronics, University of Edinburgh, Edinburgh, EH9 3JL (United Kingdom)], E-mail: p.neale@ed.ac.uk; Escher, Beate I. [Swiss Federal Institute of Aquatic Science and Technology (Eawag), 8600, Duebendorf (Switzerland); Schaefer, Andrea I. [School of Engineering and Electronics, University of Edinburgh, Edinburgh, EH9 3JL (United Kingdom)

2009-01-15

The interaction of estradiol, estrone, progesterone and testosterone with environmentally relevant concentrations of Aldrich humic acid, alginic acid and tannic acid was studied using solid-phase microextraction (SPME). Since bulk organic matter and certain hormones such as estradiol and estrone contain dissociable functional groups, the effect of pH on sorption was investigated as this will influence their fate and bioavailability. For humic acid and tannic acid, sorption was strongest at acidic pH when the bulk organic matter was in a non-dissociated form and decreased when they became partially negatively charged. At acidic and neutral pH the strength of partitioning was influenced by hormone functional groups content, with the strongest sorption observed for progesterone and estrone. At alkaline pH conditions, when the bulk organics were dissociated, sorption decreased considerably (up to a factor of 14), although the non-dissociated hormones testosterone and progesterone indicated greater sorption to humic acid at pH 10 compared to the partially deprotonated estradiol and estrone. This study demonstrates that SPME can be used to assess organic matter sorption behaviour of a selected range of micropollutants and at environmentally relevant organic matter concentrations.

Modification of SWAT model for simulation of organic matter in Korean watersheds.

Science.gov (United States)

Jang, Jae-Ho; Jung, Kwang-Wook; Gyeong Yoon, Chun

2012-01-01

The focus of water quality modeling of Korean streams needs to be shifted from dissolved oxygen to algae or organic matter. In particular, the structure of water quality models should be modified to simulate the biochemical oxygen demand (BOD), which is a key factor in calculating total maximum daily loads (TMDLs) in Korea, using 5-day BOD determined in the laboratory (Bottle BOD(5)). Considering the limitations in simulating organic matter under domestic conditions, we attempted to model total organic carbon (TOC) as well as BOD by using a watershed model. For this purpose, the Soil and Water Assessment Tool (SWAT) model was modified and extended to achieve better correspondence between the measured and simulated BOD and TOC concentrations. For simulated BOD in the period 2004-2008, the Nash-Sutcliffe model efficiency coefficient increased from a value of -2.54 to 0.61. Another indicator of organic matter, namely, the simulated TOC concentration showed that the modified SWAT adequately reflected the observed values. The improved model can be used to predict organic matter and hence, may be a potential decision-making tool for TMDLs. However, it needs further testing for longer simulation periods and other catchments.

Molecular characterization of macrophyte-derived dissolved organic matters and their implications for lakes

Science.gov (United States)

Chemical properties of whole organic matter (OM) and its dissolved organic matter (DOM) fraction from six dominant macrophytes in Lake Dianchi were comparatively characterized, and their environmental implications were discussed. Significant differences in chemical composition of the OM samples were...

Organic Matter Decomposition following Harvesting and Site Preparation of a Forested Wetland

Science.gov (United States)

Carl C. Trettin; M. Davidian; M.F. Jurgensen; R. Lea

1996-01-01

Organic matter accumulation is an important process that affects ecosystem function in many northern wetlands. The cotton strip assay (CSA)was used to measure the effect of harvesting and two different site preparation treatments, bedding and trenching, on organic matter decomposition in a forested wetland. A Latin square experimental design was used to determine the...

Characterization and morphology of solids suspended in rain water; Caracterizacion y morfologia de solidos suspendidos en agua de lluvia

Energy Technology Data Exchange (ETDEWEB)

Iturbe G, J.L.; Lopez M, B.E.; Torre O, J. De la [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, Mexico D.F. (Mexico)

2000-07-01

This work presents the results obtained from the analysis of rain water in Mexico. The study treats over the characterization and morphology of the solids suspended in form of particles in the atmosphere. The solids suspended were obtained of the pluvial precipitations after these have been centrifuged. Subsequently of the separation, the particulate matter was analysed by Sem and X-ray dispersive energy.

Rare earth elements and neodymium isotopes in sedimentary organic matter

Science.gov (United States)

Freslon, Nicolas; Bayon, Germain; Toucanne, Samuel; Bermell, Sylvain; Bollinger, Claire; Chéron, Sandrine; Etoubleau, Joel; Germain, Yoan; Khripounoff, Alexis; Ponzevera, Emmanuel; Rouget, Marie-Laure

2014-09-01

We report rare earth element (REE) and neodymium (Nd) isotope data for the organic fraction of sediments collected from various depositional environments, i.e. rivers (n = 25), estuaries (n = 18), open-ocean settings (n = 15), and cold seeps (n = 12). Sedimentary organic matter (SOM) was extracted using a mixed hydrogen peroxide/nitric acid solution (20%-H2O2-0.02 M-HNO3), after removal of carbonate and oxy-hydroxide phases with dilute hydrochloric acid (0.25 M-HCl). A series of experimental tests indicate that extraction of sedimentary organic compounds using H2O2 may be complicated occasionally by partial dissolution of sulphide minerals and residual carbonates. However, this contamination is expected to be minor for REE because measured concentrations in H2O2 leachates are about two-orders of magnitude higher than in the above mentioned phases. The mean REE concentrations determined in the H2O2 leachates for samples from rivers, estuaries, coastal seas and open-ocean settings yield relatively similar levels, with ΣREE = 109 ± 86 ppm (mean ± s; n = 58). The organic fractions leached from cold seep sediments display even higher concentration levels (285 ± 150 ppm; mean ± s; n = 12). The H2O2 leachates for most sediments exhibit remarkably similar shale-normalized REE patterns, all characterized by a mid-REE enrichment compared to the other REE. This suggests that the distribution of REE in leached sedimentary organic phases is controlled primarily by biogeochemical processes, rather than by the composition of the source from which they derive (e.g. pore, river or sea-water). The Nd isotopic compositions for organic phases leached from river sediments are very similar to those for the corresponding detrital fractions. In contrast, the SOM extracted from marine sediments display εNd values that typically range between the εNd signatures for terrestrial organic matter (inferred from the analysis of the sedimentary detrital fractions) and marine organic matter

Sorption, degradation and leaching of pesticides in soils amended with organic matter: A review

Directory of Open Access Journals (Sweden)

Fardin Sadegh-Zadeh

2017-04-01

Full Text Available The use of pesticides in modern agriculture is unavoidable because they are required to control weeds. Pesticides are poisonous; hence, they are dangerous if misused. Understanding the fate of pesticides will be useful to use them safely. Therefore, contaminations of water and soil resources could be avoided. The fates of pesticides in soils are influenced by their sorption, decomposition and movement. Degradation and leaching of pesticides are control by sorption. Soil organic matter and clay content are main soil constituents that have a high capacity for sorption of pesticides. Addition of organic maters to amend the soils is a usual practice that every year has been done in a huge area of worldwide.  The added organic amendments to the soils affect the fate of pesticides in soils as well. Pesticides fates in different soils are different. The addition of organic matter to soils causes different fates for pesticides as well. It is known from the studies that sorption of non-ionic pesticides by soil in aqueous system is controlled mainly by the organic matter content of the soils. Sorption of pesticides has been reported to increase by amending soils with organic matter. In general, conditions that promote microbial activity enhance the rate of pesticides degradation, and those that inhibit the growth of microorganisms reduce the rate of degradation. Amendment of soils with organic matter may modify leaching of pesticides in soil. Some studies showed that organic matter added to soils reduced pesticides in ground water. Generally, organic amendments induces the restriction of pesticides leaching in soils.

Distribution and disinfection of bacterial loadings associated with particulate matter fractions transported in urban wet weather flows.

Science.gov (United States)

Dickenson, Joshua A; Sansalone, John J

2012-12-15

Urban runoff is a resource for reuse water. However, runoff transports indicator and pathogenic organisms which are mobilized from sources of fecal contamination. These organisms are entrained with particulate matter (PM) that can serve as a mobile substrate for these organisms. Within a framework of additional treatment for reuse of treated runoff which requires the management of PM inventories in unit operations and drainage systems there is a need to characterize organism distributions on PM and the disinfection potential thereof. This study quantifies total coliform, Escherichia coli, fecal streptococcus, and enterococcus generated from 25 runoff events. With the ubiquity and hetero-dispersivity of PM in urban runoff this study examines organism distributions for suspended, settleable and sediment PM fractions differentiated based on PM size and transport functionality. Hypochlorite is applied in batch to elaborate inactivation of PM-associated organisms for each PM fraction. Results indicate that urban runoff bacterial loadings of indicator organisms exceed U.S. wastewater reuse, recreational contact, and Australian runoff reuse criteria as comparative metrics. All monitored events exceeded the Australian runoff reuse criteria for E. coli in non-potable residential and unrestricted access systems. In PM-differentiated events, bacteriological mobilization primarily occurred in the suspended PM fraction. However, sediment PM shielded PM-associated coliforms at all hypochlorite doses, whereas suspended and settleable PM fractions provide less shielding resulting in higher inactivation by hypochlorite. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effects of wind farm construction on concentrations and fluxes of dissolved organic carbon and suspended sediment from peat catchments at Braes of Doune, central Scotland

Directory of Open Access Journals (Sweden)

I. Grieve

2008-07-01

Full Text Available This paper assesses the impacts of disturbance associated with the construction of a wind farm on fluxes of dissolved organic carbon (DOC and suspended sediment from a blanket peat catchment in central Scotland during the period immediately following completion of construction. Six streams draining the site were sampled on six dates from October 2006, when construction was completed, and an additional three control streams to the west of the site were sampled on the same dates. Turbidity and stage were recorded semi-continuously in the two largest streams (one disturbed and one control, which were also sampled during storm events. Absorbance (400 nm and DOC concentrations were determined on all samples, and suspended sediment was determined on the event samples. Absorbance and DOC were closely correlated in both the disturbed and undisturbed streams, with slightly greater absorbance per unit DOC in the disturbed streams. DOC concentrations in disturbed tributaries were always greater than those in undisturbed streams, with mean differences ranging from 2 to around 5 mg L-1. DOC and stage were positively correlated during events with maximum concentrations in excess of 30 mg L 1 at peak flow. Suspended sediment concentrations were markedly elevated in the disturbed stream with maximum concentrations at peak flow some 4–5 times greater than in the control. The colour of the sediment suggested that it was highly organic in nature at peak flow, and suspended particulate organic carbon represented a further loss of C from the site. Using flow-weighted mean DOC concentrations calculated for the storms monitored in autumn 2007, dissolved carbon losses can be estimated for the catchments of the disturbed and control streams. From these data the additional DOC loss related to disturbance associated with the wind farm is estimated at 5 g m-2.

Response of Arabica Coffee Cultivated on Andisols on Organic Matter Applications

Directory of Open Access Journals (Sweden)

Pujiyanto .

2013-12-01

Full Text Available Andisols  are characterized  by  dominance  of  amorphous  minerals  which form strong and stable bonding with organic matter, therefore Andisols always contain high organic matter. For that reason, organic fertilizer is generally not applied  on  Andisols,  because  it  is  assumed  that  it  will  not  give   any  positive effect  on  growth  or  yield.  The  experiment  was  aimed  to  evaluate  response  of mature Kartika 1  Arabica coffee variety (seven years old cultivated on  Andisols applied with organic matter derived from cow dung manure. The experiment was carried out at Andungsari  Experimental Station located in Bondowoso District, East  Java. Elevation of the site was 1,150 m asl., with rainfall type of C (Schmidt &  Fergusson.  The  experiment  was    arranged  according  to  completely randomized  block  design  with  four  replications  to  evaluate  effect  of  ninecombination  treatments  of  application  rates  at   application  depths  of  50,  100, and 150 cm. The  range of organic fertilizers rates were  0 - 13.5 kg/tree/year. The experiment revealed that cow dung manure applications on Arabica coffee cultivated  on  Andisols  significantly  increased  yield  at  the  average  of  33% compared  to  the  untreated  crop.  No  significant  effect  of  the  treatment  onvariables of leaf water deficit and soil moisture content during dry season and root  density.  At  range  of  application  depths  of  50  -  150  cm,  the  deeper  the organic matter applications, the higher the yield will be.Key words: Andisols, Arabica coffee, organic matter, cow dung manure

Soil Quality of Restinga Forest: Organic Matter and Aluminum Saturation

Science.gov (United States)

Rodrigues Almeida Filho, Jasse; Casagrande, José Carlos; Martins Bonilha, Rodolfo; Soares, Marcio Roberto; Silva, Luiz Gabriel; Colato, Alexandre

2013-04-01

The restinga vegetation (sand coastal plain vegetation) consists of a mosaic of plant communities, which are defined by the characteristics of the substrates, resulting from the type and age of the depositional processes. This mosaic complex of vegetation types comprises restinga forest in advanced (high restinga) and medium regeneration stages (low restinga), each with particular differentiating vegetation characteristics. Of all ecosystems of the Atlantic Forest, restinga is the most fragile and susceptible to anthropic disturbances. The purpose of this study was evaluating the organic matter and aluminum saturation effects on soil quality index (SQI). Two locations were studied: State Park of the Serra do Mar, Picinguaba, in the city of Ubatuba (23°20' e 23°22' S / 44°48' e 44°52' W), and State Park of Cardoso Island in the city of Cananéia (25°03'05" e 25°18'18" S / 47°53'48" e 48° 05'42" W). The soil samples were collect at a depth of 0-10 cm, where concentrate 70% of vegetation root system. Was studied an additive model to evaluate soil quality index. The shallow root system development occurs due to low calcium levels, whose disability limits their development, but also can reflect on delay, restriction or even in the failure of the development vegetation. The organic matter is kept in the soil restinga ecosystem by high acidity, which reduces the decomposition of soil organic matter, which is very poor in nutrients. The base saturation, less than 10, was low due to low amounts of Na, K, Ca and Mg, indicating low nutritional reserve into the soil, due to very high rainfall and sandy texture, resulting in high saturation values for aluminum. Considering the critical threshold to 3% organic matter and for aluminum saturation to 40%, the IQS ranged from 0.95 to 0.1 as increased aluminum saturation and decreased the soil organic matter, indicating the main limitation to the growth of plants in this type of soil, when deforested.

Nitrogen and carbon isotopes in soil with special reference to the diagnosis of organic matter

International Nuclear Information System (INIS)

Wada, Eitaro; Nakamura, Koichi.

1980-01-01

Distributions of nitrogen and carbon isotopes in terrestrial ecosystems are described based on available data and our recent findings for soil organic matters. Major processes regulating N-isotope and C-isotope ratios in biogenic substances are discussed. The biological di-nitrogen fixation and the precipitation are major sources which lower the delta 15 N value for forested soil organic matters. Denitrification enhances delta 15 N value for soil in cultivated fields. An addition of chemical fertilizer lowers 15 N content in soils. The permiation of soil water is an important factor controlling vertical profiles of delta 15 N in soil systems. Among soil organic matters, non-hydrolizable fraction seems to give unique low delta 15 N value, suggesting the utility of delta 15 N analysis in studying the nature of the fractions. delta 13 C of soil organic matter is significantly lower than that for marine sediments. delta 13 C for soil humus varies with respect to chemical forms as well as an age of soil organic matters. The variation is large in paddy fields. It is, thus, probable that delta 13 C is an useful parameter in studying the early epidiagenesis of soil organic matters. Based on the known delta 15 N-delta 13 C relationships, a two-source mixing model has been applied to assess sources of organic matters in coastal sediment. (author)

Municipal wastewater treatment for effective removal of organic matter and nitrogen

International Nuclear Information System (INIS)

Grebenevich, E.V.; Zaletova, N.A.; Terentieva, N.A.

1987-01-01

The organic matter, as well as nitrogen and phosphorus, are nutrient substances. Their excess concentrations in water receiving bodies lead to eutrophication, moreover, the nitrogen content in water bodies is standardized according the sanitary-toxicological criterion of harmfulness: NH 4 + -N ≤0,39-2,0 mgl - , NO 3 -N ≤9,1-10 mgl - . The municipal wastewater contain, usually, organic matter estimated by BOD 150-200 mgl - , and COD 300-400 mgl - , the nitrogen compounds 50-60 mgl - , and NH 4 + -N 20-25 mgl - . NO x -N are practically absent. Their presence indicated on discharge of industrial wastewater. The total phosphorus is present in the concentration of 15 mgl - , PO 4 - - P 5-8 mgl - . Activated sludge process has been most widely used in the USSR for municipal wastewater treatment. The activated sludge is biocenoses of heterotrophic and auto trophic microorganisms. They consume nutrient matters, transferring pollution of wastewater by means of enzyme systems in acceptable forms. C, N and P-containing matters are removed from wastewater by biological intake for cell synthesis. Moreover C- containing matters are removed by oxidation to CO 2 and H 2 O. P-containing compounds under definite conditions associate with solid fraction of activated sludge and thus simultaneously removed from wastewater. The removal of nitrogen in addition to biosynthesis is carried out only in the denitrification process, when oxygen of NO x -N is used for oxidation of organic matter and produced gaseous nitrogen escapes into the atmosphere

Organic carbon deliveries and their flow related dynamics in the Fitzroy estuary

International Nuclear Information System (INIS)

Ford, Phillip; Tillman, Pei; Robson, Barbara; Webster, Ian T.

2005-01-01

The Fitzroy estuary (Queensland, Australia) receives large, but highly episodic, river flows from a catchment (144,000 km 2 ) which has undergone major land clearing. Large quantities of suspended sediments, and particulate and dissolved organic carbon are delivered. At peak flows, δ 13 C (-21.7 ± 0.8%o) and C/N (14.8 ± 1.3) of the suspended solids indicate that the particulate organic material entering the estuary is principally soil organic carbon. At the lower beginning flows the particulate organic matter comes from in-stream producers (δ 13 C = -26%o). The DOC load is about 10 times the POC load. Using the inverse method, budgets for POC and DOC were constructed for high and low flows. Under high flows, only a small portion of the POC and DOC load is lost in the estuary. Under dry season (low flow) conditions the estuary is a sink for DOC, but remains a source of POC to the coastal waters

Organic matter in North Bohemian Tertiavy and Cretaceous sediments with uranium mineralization

International Nuclear Information System (INIS)

Simanek, V.

1979-01-01

Significant variability was found in the qualitative and the quantitative compositions of dispersed organic matter in Tertiary rocks with uranium ore content between hundredths and units of percentage of the rocks. In Cretaceous rocks with similar proportion of uranium in w.% the variability is much smaller. In rocks with higher organic carbon and uranium levels the organic matter is in a more advanced stage of carbonification metamorphosis than in rocks with lower levels of the components. A statistical correlation test showed free positive correlation between the levels of uranium and organic carbon and the levels of uranium and strongly carbonified organic components and negative correlation between uranium level and humic substances on one hand and the uranium level and bitumens on the other. In Cretaceous sediments, the individual organic compounds were analytically determined in addition to the total level of organic carbon, the strongly carbonified organic components, humic substances and bitumens. Higher fatty acids in ppm concentrations were also found. Their distribution corresponds to the usual distribution in sediments. Rocks with lower contents of organic matter and uranium usually contain phenol aldehydes bound to glycosides while those with higher contents of uranium and organic carbon contain higher amounts of free phenol aldehydes. The composition of amino acids indicates genetic links to the microbial activity. (author)

Characterisation and quantification of organic phosphorus and organic nitrogen components in aquatic systems: A Review

Energy Technology Data Exchange (ETDEWEB)

Worsfold, Paul J. [School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL48AA (United Kingdom)], E-mail: pworsfold@plymouth.ac.uk; Monbet, Philippe [School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL48AA (United Kingdom); Water Studies Centre, School of Chemistry, Monash University, Clayton 3800, Victoria (Australia); Tappin, Alan D.; Fitzsimons, Mark F.; Stiles, David A. [School of Earth, Ocean and Environmental Sciences, University of Plymouth, Drake Circus, Plymouth PL48AA (United Kingdom); McKelvie, Ian D. [Water Studies Centre, School of Chemistry, Monash University, Clayton 3800, Victoria (Australia)

2008-08-22

This review provides a critical assessment of knowledge regarding the determination of organic phosphorus (OP) and organic nitrogen (ON) in aquatic systems, with an emphasis on biogeochemical considerations and analytical challenges. A general background on organic phosphorus and organic nitrogen precedes a discussion of sample collection, extraction, treatment/conditioning and preconcentration of organic phosphorus/nitrogen from sediments, including suspended particulate matter, and waters, including sediment porewaters. This is followed by sections on the determination of organic phosphorus/nitrogen components. Key techniques covered for organic phosphorus components are molecular spectrometry, atomic spectrometry and enzymatic methods. For nitrogen the focus is on the measurement of total organic nitrogen concentrations by carbon hydrogen nitrogen analysis and high temperature combustion, and organic nitrogen components by gas chromatography, high-performance liquid chromatography, gel electrophoresis, mass spectrometry, nuclear magnetic resonance spectrometry, X-ray techniques and enzymatic methods. Finally future trends and needs are discussed and recommendations made.

Processes controlling the production of aromatic water-soluble organic matter during litter decomposition

NARCIS (Netherlands)

Klotzbücher, T.; Kaiser, K.; Filley, T.R.; Kalbitz, K.

2013-01-01

Dissolved organic matter (DOM) plays a fundamental role for many soil processes. For instance, production, transport, and retention of DOM control properties and long-term storage of organic matter in mineral soils. Production of water-soluble compounds during the decomposition of plant litter is a

Bulk Soil Organic Matter d2H as a Precipitation Proxy

Science.gov (United States)

Williams, E. K.; Terwilliger, V. J.; Nakamoto, B. J.; Berhe, A. A.; Fogel, M. L.

2016-12-01

The stable hydrogen isotopic composition (d2H) of leaf waxes have traditionally been used to infer modern and paleoclimate precipitation sources. However, the extent to which evapotranspiration of leaf waters affects the d2H of plant leaf waxes remains hotly contested with offsets varying between species. Because of the relative importance of root organic matter contribution to bulk soil pools compared to litter/leaves and the minimal fractionation between soil water and root material, it is plausible that bulk soil organic matter d2H may be an option for modern and paleoclimate precipitation reconstructions. In this study, we analyzed the non-exchangeable d2H composition of roots, litter, leaves, and bulk soils along an elevation gradient in the southern Sierra Nevada range (USA). Our results show a consistent offset of 30 ± 3‰ in bulk soil organic matter in surface soils from the measured precipitation. This consistent relationship with precipitation was not found in any of the other organic materials that we measured and implies that d2H bulk soil organic matter can record precipitation signals regardless of above-ground species composition. Additionally, we utilized physical density fractionation to determine which fractions (which vary in level of mineral association and in turnover time) of the soil control this relationship. These findings and how this relationship holds with depth will be presented in conjunction with data from a soil profile on the Ethiopian plateau spanning 6000 years.

Orientation on electron transport system activity measurement in different organisms (training for Indonesian-Dutch Snellius II-expedition in 1984-1985)

NARCIS (Netherlands)

Ruyitno; Pauptit, E.; Vosjan, J.H.

1984-01-01

Preliminary experiments about ETS-activity were done in different organisms and different ecosystems; a vertebrate, an invertebrate, yeast, bacteria, methane forming consortia, suspended matter and sediment. It proved that the method is useful for the different systems but research has to be done

Effects of molecular weight of natural organic matter on cadmium mobility in soil environments and its carbon isotope characteristics

International Nuclear Information System (INIS)

Mahara, Y.; Kubota, T.; Wakayama, R.; Nakano-Ohta, T.; Nakamura, T.

2007-01-01

We investigated the role of natural organic matter in cadmium mobility in soil environments. We collected the dissolved organic matter from two different types of natural waters: pond surface water, which is oxic, and deep anoxic groundwater. The collected organic matter was fractionated into four groups with molecular weights (unit: Da (Daltons)) of 3 , 1-10 x 10 3 , 10-100 x 10 3 , and > 100 x 10 3 . The organic matter source was land plants, based on the carbon isotope ratios (δ 13 C/ 12 C). The organic matter in surface water originated from presently growing land plants, based on 14 C dating, but the organic matter in deep groundwater originated from land plants that grew approximately 4000 years ago. However, some carbon was supplied by the high-molecular-weight fraction of humic substances in soil or sediments. Cadmium interacted in a system of siliceous sand, fractionated organic matter, and water. The lowest molecular weight fraction of organic matter ( 3 ) bound more cadmium than did the higher molecular weight fractions. Organic matter in deep groundwater was more strongly bound to cadmium than was organic matter in surface water. The binding behaviours of organic matter with cadmium depended on concentration, age, molecular weight, and degradation conditions of the organic matter in natural waters. Consequently, the dissolved, low-molecular-weight fraction in organic matter strongly influences cadmium migration and mobility in the environment

Non-pharmacological modulation of cerebral white matter organization

DEFF Research Database (Denmark)

Kristensen, Tina D; Mandl, Rene C W; Jepsen, Jens R M

2018-01-01

OBJECTIVE: Neuroplasticity is a well-described phenomenon, but effects of non-pharmacological interventions on white matter (WM) are unclear. Here we review associations between active non-pharmacological interventions and WM organization in healthy subjects and in psychiatric patients. METHOD...

A Chemical Comparison of STARDUST Organics with Insoluble Organic Matter in Chondritic Meteorites

Science.gov (United States)

Cody, G. D.; Yabuta, H.; Alexander, C. M.; Araki, T.; Kilcoyne, D.

2006-12-01

We have analyzed 15 organic rich particles extracted from the aerogel capture device flown on the STARDUST mission spacecraft to comet Wild 2 using C-, N-, and O-X-ray Absorption Near Edge Structure (XANES) spectroscopy. Data were acquired with the Scanning Transmission X-ray Microscopy (STXM) beam line 5.3.2 at the Advanced Light Source, Lawrence Berkeley Laboratory. XANES can provide both quantitative molecular functional group information and atomic N/C and O/C data. We use these data to place the organic matter extracted from the Aerogel Capture device in context with a large database of C-, N-, and O-XANES spectra obtained on meteoritic Insoluble Organic Matter (IOM) obtained from type 1, 2, and 3 chondrites. We find that the organic chemistry of the particles extracted from aerogel varies in functional group abundances, but is universally very rich in heteroatoms (N and O). In several cases the organic carbon is closely associated with silica (possibly derived from the aerogel), but at a concentration far in excess of the intrinsic carbon abundance of synthesized (and flown) aerogel. Independently, 29-Si, 13-C, and 1-H solid state NMR was applied to analyze the nature of organic carbon present in the aerogel as byproduct of the synthesis. The intrinsic aerogel carbon is very simple in its functional group chemistry, very low in abundance, and differs completely from that detected in the extracted organic particles.

Time-series MODIS image-based retrieval and distribution analysis of total suspended matter concentrations in Lake Taihu (China).

Science.gov (United States)

Zhang, Yuchao; Lin, Shan; Liu, Jianping; Qian, Xin; Ge, Yi

2010-09-01

Although there has been considerable effort to use remotely sensed images to provide synoptic maps of total suspended matter (TSM), there are limited studies on universal TSM retrieval models. In this paper, we have developed a TSM retrieval model for Lake Taihu using TSM concentrations measured in situ and a time series of quasi-synchronous MODIS 250 m images from 2005. After simple geometric and atmospheric correction, we found a significant relationship (R = 0.8736, N = 166) between in situ measured TSM concentrations and MODIS band normalization difference of band 3 and band 1. From this, we retrieved TSM concentrations in eight regions of Lake Taihu in 2007 and analyzed the characteristic distribution and variation of TSM. Synoptic maps of model-estimated TSM of 2007 showed clear geographical and seasonal variations. TSM in Central Lake and Southern Lakeshore were consistently higher than in other regions, while TSM in East Taihu was generally the lowest among the regions throughout the year. Furthermore, a wide range of TSM concentrations appeared from winter to summer. TSM in winter could be several times that in summer.

Organic and Inorganic Matter in Louisiana Coastal Waters: Vermilion, Atchafalaya, Terrebonne, Barataria, and Mississippi Regions.

Science.gov (United States)

Chromophoric dissolved organic matter (CDOM) spectral absorption, dissolved organic carbon (DOC) concentration, and the particulate fraction of inorganic (PIM) and organic matter (POM) were measured in Louisiana coastal waters at Vermilion, Atchafalaya, Terrebonne, Barataria, and...

Differential recycling of coral and algal dissolved organic matter via the sponge loop

NARCIS (Netherlands)

Rix, L.; de Goeij, J.M.; van Oevelen, D.; Struck, U.; Al-Horani, F.A.; Wild, C.; Naumann, M.S.

Corals and macroalgae release large quantities of dissolved organic matter (DOM), one of the largest sources of organic matter produced on coral reefs. By rapidly taking up DOM and transforming it into particulate detritus, coral reef sponges are proposed to play a key role in transferring the

River inputs and organic matter fluxes in the northern Bay of Bengal: Fatty acids

Digital Repository Service at National Institute of Oceanography (India)

Reemtsma, T.; Ittekkot, V.; Bartsch, M.; Nair, R.R

) 55-71 55 Elsevier Science Publishers B.V., Amsterdam \\[RA\\] River inputs and organic matter fluxes in the northern Bay of Bengal: fatty acids T. Reemtsma a, V. Ittekkot a, M. Bartsch a and R.R. Nair b alnstitut fiir Biogeochemie und Meereschemie..., R.R., 1993. River inputs and organic matter fluxes in the northern Bay of Bengal: fatty acids. Chem. Geol., 103: 55-71. Total particulate matter flux and organic carbon and fatty acid fluxes associated with settling particles collected during...

Missing links in the root-soil organic matter continuum

Energy Technology Data Exchange (ETDEWEB)

O' Brien, Sarah L. [Argonne National Laboratory (ANL); Iversen, Colleen M [ORNL

2009-01-01

The soil environment remains one of the most complex and poorly understood research frontiers in ecology. Soil organic matter (SOM), which spans a continuum from fresh detritus to highly processed, mineral-associated organic matter, is the foundation of sustainable terrestrial ecosystems. Heterogeneous SOM pools are fueled by inputs from living and dead plants, driven by the activity of micro- and mesofauna, and are shaped by a multitude of abiotic factors. The specialization required to measure unseen processes that occur on a wide range of spatial and temporal scales has led to the partitioning of soil ecology research across several disciplines. In the organized oral session 'Missing links in the root-soil organic matter continuum' at the annual Ecological Society of America meeting in Albuquerque, NM, USA, we joined the call for greater communication and collaboration among ecologists who work at the root-soil interface (e.g. Coleman, 2008). Our goal was to bridge the gap between scientific disciplines and to synthesize disconnected pieces of knowledge from root-centric and soil-centric studies into an integrated understanding of belowground ecosystem processes. We focused this report around three compelling themes that arose from the session: (1) the influence of the rhizosphere on SOM cycling, (2) the role of soil heterotrophs in driving the transformation of root detritus to SOM, and (3) the controlling influence of the soil environment on SOM dynamics. We conclude with a discussion of new approaches for gathering data to bridge gaps in the root-SOM continuum and to inform the next generation of ecosystem models. Although leaf litter has often been considered to be the main source of organic inputs to soil, Ann Russell synthesized a convincing body of work demonstrating that roots, rather than surface residues, control the accumulation of SOM in a variety of ecosystems. Living roots, which are chemically diverse and highly dynamic, also influence a

Carbon isotope ratios of organic matter in Bering Sea settling particles. Extremely high remineralization of organic carbon derived from diatoms

International Nuclear Information System (INIS)

Yasuda, Saki; Akagi, Tasuku; Naraoka, Hiroshi; Kitajima, Fumio; Takahashi, Kozo

2016-01-01

The carbon isotope ratios of organic carbon in settling particles collected in the highly-diatom-productive Bering Sea were determined. Wet decomposition was employed to oxidize relatively fresh organic matter. The amount of unoxidised organic carbon in the residue following wet decomposition was negligible. The δ 13 C of organic carbon in the settling particles showed a clear relationship against SiO 2 /CaCO 3 ratio of settling particles: approximately -26‰ and -19‰ at lower and higher SiO 2 /CaCO 3 ratios, respectively. The δ 13 C values were largely interpreted in terms of mixing of two major plankton sources. Both δ 13 C and compositional data can be explained consistently only by assuming that more than 98% of diatomaceous organic matter decays and that organic matter derived from carbonate-shelled plankton may remain much less remineralized. A greater amount of diatom-derived organic matter is discovered to be trapped with the increase of SiO 2 /CaCO 3 ratio of the settling particles. The ratio of organic carbon to inorganic carbon, known as the rain ratio, therefore, tends to increase proportionally with the SiO 2 /CaCO 3 ratio under an extremely diatom-productive condition. (author)

Organic matter degradation in Chilean sediments - following nature's own degradation experiment

DEFF Research Database (Denmark)

Langerhuus, Alice Thoft; Niggemann, Jutta; Lomstein, Bente Aagaard

ORGANIC MATTER DEGRADATION IN CHILEAN SEDIMENTS – FOLLOWING NATURE’S OWN DEGRADATION EXPERIMENT Degradation of sedimentary organic matter was studied at two stations from the shelf of the Chilean upwelling region. Sediment cores were taken at 1200 m and 800 m water depth and were 4.5 m and 7.5 m...... in length, respectively. The objective of this study was to assess the degradability of the organic matter from the sediment surface to the deep sediments. This was done by analysing amino acids (both L- and D-isomers) and amino sugars in the sediment cores, covering a timescale of 15.000 years. Diagenetic...... indicators (percentage of carbon and nitrogen present as amino acid carbon and nitrogen, the ratio between a protein precursor and its non-protein degradation product and the percentage of D-amino acids) revealed ongoing degradation in these sediments, indicating that microorganisms were still active in 15...

Comparison of two treatments for the removal of selected organic micropollutants and bulk organic matter: conventional activated sludge followed by ultrafiltration versus membrane bioreactor.

Science.gov (United States)

Sahar, E; Ernst, M; Godehardt, M; Hein, A; Herr, J; Kazner, C; Melin, T; Cikurel, H; Aharoni, A; Messalem, R; Brenner, A; Jekel, M

2011-01-01

The potential of membrane bioreactor (MBR) systems to remove organic micropollutants was investigated at different scales, operational conditions, and locations. The effluent quality of the MBR system was compared with that of a plant combining conventional activated sludge (CAS) followed by ultrafiltration (UF). The MBR and CAS-UF systems were operated and tested in parallel. An MBR pilot plant in Israel was operated for over a year at a mixed liquor suspended solids (MLSS) range of 2.8-10.6 g/L. The MBR achieved removal rates comparable to those of a CAS-UF plant at the Tel-Aviv wastewater treatment plant (WWTP) for macrolide antibiotics such as roxythromycin, clarithromycin, and erythromycin and slightly higher removal rates than the CAS-UF for sulfonamides. A laboratory scale MBR unit in Berlin - at an MLSS of 6-9 g/L - showed better removal rates for macrolide antibiotics, trimethoprim, and 5-tolyltriazole compared to the CAS process of the Ruhleben sewage treatment plant (STP) in Berlin when both were fed with identical quality raw wastewater. The Berlin CAS exhibited significantly better benzotriazole removal and slightly better sulfamethoxazole and 4-tolyltriazole removal than its MBR counterpart. Pilot MBR tests (MLSS of 12 g/L) in Aachen, Germany, showed that operating flux significantly affected the resulting membrane fouling rate, but the removal rates of dissolved organic matter and of bisphenol A were not affected.

Modelling of suspended matter transport and turnover in biofilters for waste water treatment; Modellierung von Stofftransport und -umsatz in Biofiltern zur Abwasserreinigung

Energy Technology Data Exchange (ETDEWEB)

Telgmann, U. [Kassel Univ. (Gesamthochschule) (Germany). Fachgebiet Siedlungswasserwirtschaft; Horn, H. [Fachhochschule Magdeburg (Germany). Hydro- und Abfallchemie

1999-07-01

Essential elements of the presented model for biofilters are suspended matter transfer in the boundary layer water/biofilm, the gradient of concentration for substrate turnover in the biofilm with limited diffusion, and the gradient of concentration and biomass distribution both in the biofilm and over the height of the reactor. Problematic in biofilm modelling is linking the turnover of substrate in the biofilm affixed to the carrier material with changes in concentration along the reactor height. This means that concentration profiles need to be calculated both in the biofilm and over the height of the reactor. The presented model describes substrate turnover in the biofilm by means of a Monod kinetics, and diffusive suspended matter transport with the aid of Fick's second law. The change in concentration over the filter bed height is taken into account by dividing the reactor volume into five complete-mixing segments. Further elements of modelling are biomass production and the corresponding discharge from the biofilter. In exemplary manner, a biofilter for downstream denitrification with methanol was modelled and the results were compared with measurements taken at a semi-technical pilot plant. (orig.) [German] Wesentliche Elemente des hier vorgestellten Modells fuer Biofilter sind der Stoffuebergang in der Grenzschicht Wasser/Biofilm, der Konzentrationsgradient beim diffusionslimitierten Substratumsatz im Biofilm, der Konzentrationsgradient und die Biomasseverteilung sowohl im Biofilm als auch ueber die Reaktorhoehe. Problematik bei der Modellierung eines Biofilms ist die Verknuepfung von Substratumsatz in dem auf dem Traegermaterial haftenden Biofilm mit der Konzentrationsveraenderung entlang der Reaktorhoehe. Die Konzentrationsprofile muessen also sowohl im Biofilm als auch ueber die Reaktorhoehe berechnet werden. Im praesentierten Modell wird der Substratumsatz im Biofilm mit einer Monodkinetik und der diffusive Stofftransport mit Hilfe des 2. Fick

Basic microscopic theory of the distribution, transfer and uptake kinetics of dissolved radionuclides by suspended particulate matter - Part I; Theory development

International Nuclear Information System (INIS)

Abril, J.M.

1998-01-01

Recently much experimental effort has been focused on determining those factors which affect the kinetics and the final equilibrium conditions for the uptake of radionuclides from the aqueous phase by particulate matter. At present, some of these results appear to be either surprising or contradictory and introduce some uncertainty in which parameter values are most appropriate for environmental modelling. In this paper, we study the ionic exchange between the dissolved phase and suspended particles from a microscopic viewpoint, developing a mathematical description of the kinetic transfer and the k d distribution coefficients. The most relevant contribution is the assumption that the exchange of radionuclides occurs in a specific surface layer on the particles, with a non-zero thickness. A wide range of experimental findings can be explained with this theory. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

Influence of environmental factors on spectral characteristics of chromophoric dissolved organic matter (CDOM) in Inner Mongolia Plateau, China

Science.gov (United States)

Wen, Z. D.; Song, K. S.; Zhao, Y.; Du, J.; Ma, J. H.

2016-02-01

Spectral characteristics of chromophoric dissolved organic matter (CDOM) were examined in conjunction with environmental factors in the waters of rivers and terminal lakes within the Hulun Buir plateau, northeast China. Dissolved organic carbon (DOC), total nitrogen (TN), and total phosphorous (TP) were significantly higher in terminal lakes than rivers waters (p CDOM absorption in river waters was significantly lower than terminal lakes. Analysis of the ratio of absorption at 250 to 365 nm (E250 : 365), specific ultraviolet (UV) absorbance (SUVA254), and the spectral slope ratio (Sr) indicated that CDOM in river waters had higher aromaticity, molecular weight, and vascular plant contribution than in terminal lakes. Furthermore, results showed that DOC concentration, CDOM light absorption, and the proportion of autochthonous sources of CDOM in plateau waters were all higher than in other freshwater rivers reported in the literature. The strong evapoconcentration, intense ultraviolet irradiance, and landscape features of the Hulun Buir plateau may be responsible for the above phenomenon. Redundancy analysis (RDA) indicated that the environmental variables total suspended matter (TSM), TN, and electrical conductivity (EC) had a strong correlation with light absorption characteristics, followed by total dissolved solid (TDS) and chlorophyll a. In most sampling locations, CDOM was the dominant non-water light-absorbing substance. Light absorption by non-algal particles often exceeded that by phytoplankton in the plateau waters. Study of these optical-physicochemical correlations is helpful in the evaluation of the potential influence of water quality factors on non-water light absorption in cold plateau water environments. The construction of a correlation between DOC concentration and water quality factors may help contribute to regional estimates of carbon sources and fate for catchment carbon budget assessments.

Optical Algorithms at Satellite Wavelengths for Total Suspended Matter in Tropical Coastal Waters.

Science.gov (United States)

Ouillon, Sylvain; Douillet, Pascal; Petrenko, Anne; Neveux, Jacques; Dupouy, Cécile; Froidefond, Jean-Marie; Andréfouët, Serge; Muñoz-Caravaca, Alain

2008-07-10

Is it possible to derive accurately Total Suspended Matter concentration or its proxy, turbidity, from remote sensing data in tropical coastal lagoon waters? To investigate this question, hyperspectral remote sensing reflectance, turbidity and chlorophyll pigment concentration were measured in three coral reef lagoons. The three sites enabled us to get data over very diverse environments: oligotrophic and sediment-poor waters in the southwest lagoon of New Caledonia, eutrophic waters in the Cienfuegos Bay (Cuba), and sediment-rich waters in the Laucala Bay (Fiji). In this paper, optical algorithms for turbidity are presented per site based on 113 stations in New Caledonia, 24 stations in Cuba and 56 stations in Fiji. Empirical algorithms are tested at satellite wavebands useful to coastal applications. Global algorithms are also derived for the merged data set (193 stations). The performances of global and local regression algorithms are compared. The best one-band algorithms on all the measurements are obtained at 681 nm using either a polynomial or a power model. The best two-band algorithms are obtained with R412/R620, R443/R670 and R510/R681. Two three-band algorithms based on Rrs620.Rrs681/Rrs412 and Rrs620.Rrs681/Rrs510 also give fair regression statistics. Finally, we propose a global algorithm based on one or three bands: turbidity is first calculated from Rrs681 and then, if turbidity range and for the three sites sampled (mean bias: 3.6 %, rms: 35%, mean quadratic error: 1.4 FTU). This shows that defining global empirical turbidity algorithms in tropical coastal waters is at reach.

Organic Matter Quality and its Influence on Carbon Turnover and Stabilization in Northern Peatlands

Science.gov (United States)

Turetsky, M. R.; Wieder, R. K.

2002-12-01

Peatlands cover 3-5 % of the world's ice-free land area, but store about 33 % of global terrestrial soil carbon. Peat accumulation in northern regions generally is controlled by slow decomposition, which may be limited by cold temperatures and water-logging. Poor organic matter quality also may limit decay, and microbial activity in peatlands likely is regulated by the availability of labile carbon and/or nutrients. Conversely, carbon in recalcitrant soil structures may be chemically protected from microbial decay, particularly in peatlands where carbon can be buried in anaerobic soils. Soil organic matter quality is controlled by plant litter chemical composition and the susceptibility of organic compounds to decomposition through time. There are a number of techniques available for characterizing organic quality, ranging from chemical proximate or elemental analysis to more qualitative methods such as nuclear magenetic resonance, pyrolysis/mass spectroscopy, and Fourier transform infrared spectroscopy. We generally have relied on proximate analysis for quantitative determination of several organic fractions (i.e., water-soluble carbohydrates, soluble nonpolars, water-soluble phenolics, holocellulose, and acid insoluble material). Our approaches to studying organic matter quality in relation to C turnover in peatlands include 1) 14C labelling of peatland vegetation along a latitudinal gradient in North America, allowing us to follow the fate of 14C tracer in belowground organic fractions under varying climates, 2) litter bag studies focusing on the role of individual moss species in litter quality and organic matter decomposition, and 3) laboratory incubations of peat to explore relationships between organic matter quality and decay. These studies suggest that proximate organic fractions vary in lability, but that turnover of organic matter is influenced both by plant species and climate. Across boreal peatlands, measures of soil recalcitrance such as acid

Organic matter cycling in a neotropical reservoir: effects of temperature and experimental conditions

Directory of Open Access Journals (Sweden)

Flávia Bottino

2013-06-01

Full Text Available AIM:This study reports a comparison between decomposition kinetics of detritus derived from two macrophyte species (Polygonum lapathifolium L.: Polygonaceae; Eichhornia azurea (Sw. Kunth.: Pontederiaceae growing in a neotropical reservoir (Brazil, under laboratory and field conditions, in order to assess hypotheses on the main differences in factors affecting organic matter cycling, including the effect of temperature. METHODS: Plant and water samples were collected from the reservoir in August 2009. In field incubation mass loss was assessed using a litter bag technique and in the laboratory the decay was followed using a decomposition chamber maintained under controlled conditions (i.e. in the dark, at 15 ºC and 25 ºC. A kinetic model was adopted to explain and compare the organic matter decay, ANOVA (Repeated Measures testing was used to describe the differences between the treatments and a linear correlation was used to compare in situ and in vitro experiments. RESULTS: The mass decay was faster in natural conditions with rapid release of the labile-soluble portion. The simulated values of mineralization rates of dissolved organic matter and refractory organic matter were rapid in high temperatures (25 ºC. The high Q10 results (mainly for E. azurea, and experimental conditions, and outcomes of ANOVA testing indicate the temperature variation (10 ºC influence the rates of mass decay. CONCLUSIONS: The results suggested rapid organic matter cycling in warm months (from October to December supporting the microbial loop. Although the particulate organic matter losses are high in field conditions the results are of the same magnitude in both conditions suggesting an equivalence of the mass decay kinetic.

Transformation of soil organic matter in a Japanese larch forest. Radiocarbon and stable carbon isotope compositions versus soil depth

International Nuclear Information System (INIS)

Liu Wei; Moriizumi, Jun; Yamazawa, Hiromi; Iida, Takao

2008-01-01

Soil organic matter at a depth of 0-55 cm, collected from a Japanese larch forest area, was separated into particulate organic matter (size >53 μm), particulate organic matter (size 14 C and δ 13 C values were determined. The Δ 14 C values of particulate matters decreased greatly from 128 per mille to -278 per mille, indicating a relative increase of resistant organic components in particulate matters. That of humic acid matter decreased from 183 per mille to -139 per mille. For these of organic matter fractions at the same depth, the Δ 14 C values of particulate matter (size >53μm) are smallest and those of humic acid matter are the largest. That indicates that a high contribution of young organic matter to the humic acid matter exists and transformation tendency of particulate matter may be from coarse to small in the particulate size. Positive Δ 14 C values appeared at a depth of 10 cm, 25 cm, and 35 cm for the particulate organic matter (size >53μm), particulate organic matter (size 14 C values of the humic acid matter also infects that the bomb carbon has reached the depth of 35 cm. Additionally, the Δ 14 C values of these three kinds of organic matters ranged from 50 per mille to 183 per mille at a depth of 0-7 cm, which were not smaller than that of litter in the forest area, indicating high proportion of modern, plants-derived soil organic matter in this depth ranges. The δ 13 C values increased from -28 per mille to -23 per mille with the increase depth of 0-55 cm. The δ 13 C values of humic acid matter are approximately less than that of particulate matters at the same depth, which may be explained as a high contribution of young organic matter to the humic acid matter. (author)

Flexibility of Enzymes Suspended in Organic Solvents Probed by Time-Resolved Fluorescence Anisotropy. Evidence That Enzyme Activity and Enantioselectivity Are Directly Related to Enzyme Flexibility

NARCIS (Netherlands)

Broos, Jaap; Visser, Antonie J.W.G.; Engbersen, Johan F.J.; Verboom, Willem; Hoek, Arie van; Reinhoudt, David N.

1995-01-01

A time-resolved fluorescence anisotropy study on the molecular flexibility of active-site labeled anthraniloyl-α-chymotrypsin, dansylsubtilisin Carlsberg, and native subtilisin Carlsberg, suspended in organic solvents, is described. The internal rotational mobility of the fluorophore in the

Quality of fresh organic matter affects priming of soil organic matter and substrate utilization patterns of microbes

Science.gov (United States)

Wang, Hui; Boutton, Thomas W.; Xu, Wenhua; Hu, Guoqing; Jiang, Ping; Bai, Edith

2015-05-01

Changes in biogeochemical cycles and the climate system due to human activities are expected to change the quantity and quality of plant litter inputs to soils. How changing quality of fresh organic matter (FOM) might influence the priming effect (PE) on soil organic matter (SOM) mineralization is still under debate. Here we determined the PE induced by two 13C-labeled FOMs with contrasting nutritional quality (leaf vs. stalk of Zea mays L.). Soils from two different forest types yielded consistent results: soils amended with leaf tissue switched faster from negative PE to positive PE due to greater microbial growth compared to soils amended with stalks. However, after 16 d of incubation, soils amended with stalks had a higher PE than those amended with leaf. Phospholipid fatty acid (PLFA) results suggested that microbial demand for carbon and other nutrients was one of the major determinants of the PE observed. Therefore, consideration of both microbial demands for nutrients and FOM supply simultaneously is essential to understand the underlying mechanisms of PE. Our study provided evidence that changes in FOM quality could affect microbial utilization of substrate and PE on SOM mineralization, which may exacerbate global warming problems under future climate change.

CHROMOPHORIC DISSOLVED ORGANIC MATTER (CDOM) DERIVED FROM DECOMPOSITION OF VARIOUS VASCULAR PLANT AND ALGAL SOURCES

Science.gov (United States)

Chromophoric dissolved organic (CDOM) in aquatic environments is derived from the microbial decomposition of terrestrial and microbial organic matter. Here we present results of studies of the spectral properties and photoreactivity of the CDOM derived from several organic matter...

Nitrogen isotopic composition of macromolecular organic matter in interplanetary dust particles

Science.gov (United States)

Aléon, Jérôme; Robert, François; Chaussidon, Marc; Marty, Bernard

2003-10-01

Nitrogen concentrations and isotopic compositions were measured by ion microprobe scanning imaging in two interplanetary dust particles L2021 K1 and L2036 E22, in which imaging of D/H and C/H ratios has previously evidenced the presence of D-rich macromolecular organic components. High nitrogen concentrations of 10-20 wt% and δ 15N values up to +400‰ are observed in these D-rich macromolecular components. The previous study of D/H and C/H ratios has revealed three different D-rich macromolecular phases. The one previously ascribed to macromolecular organic matter akin the insoluble organic matter (IOM) from carbonaceous chondrites is enriched in nitrogen by one order of magnitude compared to the carbonaceous chondrite IOM, although its isotopic composition is still similar to what is known from Renazzo (δ 15N = +208‰). The correlation observed in macromolecular organic material between the D- and 15N-excesses suggests that the latter originate probably from chemical reactions typical of the cold interstellar medium. These interstellar materials preserved to some extent in IDPs are therefore macromolecular organic components with various aliphaticity and aromaticity. They are heavily N-heterosubstituted as shown by their high nitrogen concentrations >10 wt%. They have high D/H ratios >10 -3 and δ 15N values ≥ +400‰. In L2021 K1 a mixture is observed at the micron scale between interstellar and chondritic-like organic phases. This indicates that some IDPs contain organic materials processed at various heliocentric distances in a turbulent nebula. Comparison with observation in comets suggests that these molecules may be cometary macromolecules. A correlation is observed between the D/H ratios and δ 15N values of macromolecular organic matter from IDPs, meteorites, the Earth and of major nebular reservoirs. This suggests that most macromolecular organic matter in the inner solar system was probably issued from interstellar precursors and further processed

Input related microbial carbon dynamic of soil organic matter in particle size fractions

Science.gov (United States)

Gude, A.; Kandeler, E.; Gleixner, G.

2012-04-01

This paper investigated the flow of carbon into different groups of soil microorganisms isolated from different particle size fractions. Two agricultural sites of contrasting organic matter input were compared. Both soils had been submitted to vegetation change from C3 (Rye/Wheat) to C4 (Maize) plants, 25 and 45 years ago. Soil carbon was separated into one fast-degrading particulate organic matter fraction (POM) and one slow-degrading organo-mineral fraction (OMF). The structure of the soil microbial community were investigated using phospholipid fatty acids (PLFA), and turnover of single PLFAs was calculated from the changes in their 13C content. Soil enzyme activities involved in the degradation of carbohydrates was determined using fluorogenic MUF (methyl-umbelliferryl phosphate) substrates. We found that fresh organic matter input drives soil organic matter dynamic. Higher annual input of fresh organic matter resulted in a higher amount of fungal biomass in the POM-fraction and shorter mean residence times. Fungal activity therefore seems essential for the decomposition and incorporation of organic matter input into the soil. As a consequence, limited litter input changed especially the fungal community favouring arbuscular mycorrhizal fungi. Altogether, supply and availability of fresh plant carbon changed the distribution of microbial biomass, the microbial community structure and enzyme activities and resulted in different priming of soil organic matter. Most interestingly we found that only at low input the OMF fraction had significantly higher calculated MRT for Gram-positive and Gram-negative bacteria suggesting high recycling of soil carbon or the use of other carbon sources. But on average all microbial groups had nearly similar carbon uptake rates in all fractions and both soils, which contrasted the turnover times of bulk carbon. Hereby the microbial carbon turnover was always faster than the soil organic carbon turnover and higher carbon input

Soil erosion and organic matter loss by using fallout 137Cs as tracer in Miyun reservoir valley

International Nuclear Information System (INIS)

Hua Luo; Zhang Zhigang; Li Junbo; Feng Yan; Zhao Hong; Yin Xunxiao; Zhu Fengyun

2005-01-01

Miyun reservoir is one of the important water sources for Beijing, the water quality of the reservoir is directly influenced by soil erosion. Based on measuring the 137 Cs concentrations, organic content in the soil of selected sampling sites, the authors investigated the relationship between the quality of soil erosion and organic matters. According to classificatory standards of soil erosion, the intensity of erosion in Miyun reservoir valley is light and moderate, but in some parts erosion is serious. The land use model has dramatic influence on distribution of organic matters in the soil. Unreasonable human activities could cause serious increase of organic matter runoff and soil erosion intensity. Distributions of organic matters were increased in the following order: bush land > forestry > orchard > farmland. Organic matters in the upper course were higher than in the circumference of reservoir. The simulated model suggests that there is a cubic relation between the contents of organic matters and 137 Cs concentrations (r 2 =0.9). The math model in the single sights can forecast soil erosion and changes of concentrations of organic matters in the soils, so that the chemical analysis and measurements are simplified. (authors)

Influence of light-weight organic matters on strontium sorption to bentonite

International Nuclear Information System (INIS)

Wang, Tsing-Hai; Wu, Ding-Chiang; Teng, Shi-Ping

2010-01-01

Document available in extended abstract form only. Light-weight organic matters were frequently observed in groundwater. Their existence had significant influence on the transport of radionuclides. In this study, light-weight organic acid species including oxalic (MW 90), succinic (MW 118), adipic (MW 146), azelaic (MW 188), eicosanedioic (MW 306), benzoic (MW 122), salicylic (MW 138), and gallic (MW 170) were selected as the surrogate of natural organic matters. Their effects on strontium sorption to bentonite were evaluated by using a surface complexation model MINEQL+. Under this framework, three sorption mechanisms were considered: 1. structure sorption sites, 2. edge sorption sites, 3. further hydration of adsorbed Sr 2+ . The presence of organic species had no influence on Sr cation sorption to structure sorption sites. However, Sr cation sorption to edge sorption was affected by the organics to certain extent. For example, sorption capability of edge sites toward Sr was increased by the gallic species. Furthermore, hydration of adsorbed Sr was significantly affected by the presence of organic species. This might relate to that adsorbed Sr would become the bridge associating organic species on bentonite surfaces, but this argument required more solid spectral evidences to support. Some preliminary observations on Sr sorption to bentonite were obtained in this work; however, further experiments are still required by conducting experiments with more variety of organic species. By doing a comprehensive study, it would be much beneficial to make a more accurate evaluation of the influence of organic matters on Sr sorption

The effect of gamma irradiation on the digestibility of organic matter of poultry excreta (In vitro)

International Nuclear Information System (INIS)

Al-Masri, M.R.

1993-07-01

The changes in the digestibility of dry matter and organic matter by enzyme (in vitro) for two types of the excreta of laying hens were studied. In type I, excreta were dried at 170-180 C for 10 minutes whereas in type II dried at 55-60 C for several days. Each type was divided into two parts, the first stored for 3 months with the control. The second part was irradiated by gamma irradiation at 100 KGy and stored for 3 months with the control. The results indicated that there was significant (0.05) difference in the digestibility of dry matter and organic matter and the percentage of crude fibre between samples and the control for the types I and II before and after storage. The dry matter digestibility for types I and II increased by 7%, and the organic matter digestibility increased by 17% for type I and by 11% for type II before and after storage. The increase in the digestibility of dry matter and organic matter is attributed to the decrease in crude fibre obtained by irradiation. The storage of excreta after drying has no effects on the rate of increase in the digestibility of dry matter and organic matter due to irradiation in both types (I and II). (author). 19 refs., 5 figs., 4 tabs

Sorption of polycyclic aromatic hydrocarbons on particulate organic matters

International Nuclear Information System (INIS)

Guo Xueyan; Luo Lei; Ma Yibing; Zhang Shuzhen

2010-01-01

Particulate organic matter (POM) is a key organic matter fraction which can influence soil fertility. Its interactions with hydrophobic organic pollutants (HOCs) have not been characterized and the mechanisms of retention of HOCs by POM remain unclear. In the present study, sorption behaviors of polycyclic aromatic hydrocarbons (PAHs) naphthalene (NAP), phenanthrene (PHE), and pyrene (PYR) by POMs separated from different soils were examined and the POMs were characterized by elemental analysis, solid state 13 C NMR, and Fourier transform infrared spectroscopy (FT-IR). The results indicated that POMs were mainly composed of aliphatic components with high polarity. The different original POMs showed similar chemical composition and configuration. Sorption behaviors of PAHs indicated that there was no significant difference in sorption capacity among the POMs. Sorption of NAP and PHE by POMs displayed a nonlinear isotherm, while sorption of PYR yielded a linear isotherm. No significant hysteresis and ionic strength effect were observed for PAH desorption from the POMs.

Overestimation of Crop Root Biomass in Field Experiments Due to Extraneous Organic Matter.

Science.gov (United States)

Hirte, Juliane; Leifeld, Jens; Abiven, Samuel; Oberholzer, Hans-Rudolf; Hammelehle, Andreas; Mayer, Jochen

2017-01-01

Root biomass is one of the most relevant root parameters for studies of plant response to environmental change, soil carbon modeling or estimations of soil carbon sequestration. A major source of error in root biomass quantification of agricultural crops in the field is the presence of extraneous organic matter in soil: dead roots from previous crops, weed roots, incorporated above ground plant residues and organic soil amendments, or remnants of soil fauna. Using the isotopic difference between recent maize root biomass and predominantly C3-derived extraneous organic matter, we determined the proportions of maize root biomass carbon of total carbon in root samples from the Swiss long-term field trial "DOK." We additionally evaluated the effects of agricultural management (bio-organic and conventional), sampling depth (0-0.25, 0.25-0.5, 0.5-0.75 m) and position (within and between maize rows), and root size class (coarse and fine roots) as defined by sieve mesh size (2 and 0.5 mm) on those proportions, and quantified the success rate of manual exclusion of extraneous organic matter from root samples. Only 60% of the root mass that we retrieved from field soil cores was actual maize root biomass from the current season. While the proportions of maize root biomass carbon were not affected by agricultural management, they increased consistently with soil depth, were higher within than between maize rows, and were higher in coarse (>2 mm) than in fine (≤2 and >0.5) root samples. The success rate of manual exclusion of extraneous organic matter from root samples was related to agricultural management and, at best, about 60%. We assume that the composition of extraneous organic matter is strongly influenced by agricultural management and soil depth and governs the effect size of the investigated factors. Extraneous organic matter may result in severe overestimation of recovered root biomass and has, therefore, large implications for soil carbon modeling and estimations

Nitrogen Isotopic Composition of Organic Matter in a Pristine Collection IDP

Science.gov (United States)

Messenger, S.; Nakamura-Messenger, K.; Keller, L. P.; Clemett, S. J.; Nguyen, A. N.; Walker, Robert M.

2012-01-01

Anhydrous chondritic porous interplanetary dust particles (CP IDPs) are probable cometary materials that show primitive characteristics, such as unequilibrated mineralogy, fragile structure, and abundant presolar grains and organic matter [1-3]. CP IDPs are richer in aliphatic species and N-bearing aromatic hydrocarbons than meteoritic organics and commonly exhibit highly anomalous H and N isotopic compositions [4,5]. Cometary organic matter is of interest in part because it has escaped the hydrothermal processing experienced by meteorites. However, IDPs are collected using silicon oil that must be removed with strong organic solvents such as hexane. This procedure is likely to have removed some fraction of soluble organic phases in IDPs. We recently reported the first stratospheric collection of IDPs without the use of silicone oil [6]. Here we present initial studies of the carbonaceous material in an IDP from this collection.

Evaluation of the symbiotic nitrogen fixation in soybean by labelling of soil organic matter

International Nuclear Information System (INIS)

Ruschel, A.P.; Freitas, J.R. de; Vose, P.B.

1982-01-01

An experiment was carried out using the isotopic dilution method to evaluate symbiotic nitrogen fixation in soybean grown in soil labelled with 15 N enriched organic matter. Symbiotic N 2 -fixed was 71-76% of total N in the plant. Non nodulated soybean utilized 56-59% N from organic matter and 40% from soil. Roots of nodulated plants had lower NdN 2 than aereal plant parts. The advantage of using labelled organic matter as compared with 15 N-fertilizer addition in evaluating N 2 -fixation is discussed. (Author) [pt

The role of aquatic fungi in transformations of organic matter mediated by nutrients

Science.gov (United States)

Cynthia J. Tant; Amy D. Rosemond; Andrew S. Mehring; Kevin A. Kuehn; John M. Davis

2015-01-01

1. We assessed the key role of aquatic fungi in modifying coarse particulate organic matter (CPOM) by affecting its breakdown rate, nutrient concentration and conversion to fine particulate organic matter (FPOM). Overall, we hypothesised that fungal-mediated conditioning and breakdown of CPOM would be accelerated when nutrient concentrations are increased and tested...

Management of organic matter in the tropics: Translating theory into practice

NARCIS (Netherlands)

Palm, C.A.; Giller, K.E.; Mafongoya, P.L.; Swift, M.J.

2001-01-01

Inputs of organic materials play a central role in the productivity of many tropical farming systems by providing nutrients through decomposition and substrate for synthesis of soil organic matter (SOM). The organic inputs in many tropical farming systems such as crop residues, manures, and natural

Multiscale organisation of organic matter associated with gold and uranium minerals in the Witwatersrand basin, South Africa

Energy Technology Data Exchange (ETDEWEB)

Smieja-Krol, Beata; Duber, Stanislaw [Faculty of Earth Science, University of Silesia, 60 Bedzinska St., 41-200 Sosnowiec (Poland); Rouzaud, Jean-Noel [Laboratoire de Geologie, Ecole Normale Superieure, 24, rue Lhomond, 75231 Paris Cedex 5 (France)

2009-03-01

Organic matter from the northern part of the Early Proterozoic Witwatersrand basin (Carbon Leader reef) was investigated using optical (OM) and transmission electron (TEM) microscopes, completed by XRD analysis. The multiscale organization (texture, microtexture, structure) of the organic matter was observed in order to gain information about the processes which affected organic material after its deposition in sediments. In the micrometre scale (optical microscope), the shape and size of the Reflectance Indicating Surface (RIS) of the organic matter were determined. The organic matter reveals a prevailing biaxial symmetry. The size of RIS is generally dependent on uranium and increases with increasing uranium concentration. Furthermore, it appears that more than one RIS is present within the scale of a single sample, each with a different symmetry and size. The presence of domains differing in organisation of the aromatic framework was confirmed by TEM observation in the DF mode. The aromatic skeleton of organic matter is composed of short, often crumpled, mostly isolated (non-stacked) polyaromatic layers whose fringe length corresponds to 3-16 aromatic rings. The data indicate reorganization of the polyaromatic organic matter structure under stress in high pressure and relatively low temperature conditions. The organic matter was in a solid state within the rocks before the pressure event. (author)

Organic matter distribution in the continental shelf sediments, off Kochi, west coast of India

Digital Repository Service at National Institute of Oceanography (India)

Reddy, N.P.C.

(average 3.8%) than those towards Azhikode (average 1.97%). The sand predominant offshore relict sediments contain very low organic matter values (average 0.71%). The high organic matter content in the inner shelf is mainly controlled by the fine texture...

Investigation of the organic matter in inactive nuclear tank liquids

International Nuclear Information System (INIS)

Schenley, R.L.; Griest, W.H.

1990-08-01

Environmental Protection Agency (EPA) methodology for regulatory organics fails to account for the organic matter that is suggested by total organic carbon (TOC) analysis in the Oak Ridge National Laboratory (ORNL) inactive nuclear waste-tank liquids and sludges. Identification and measurement of the total organics are needed to select appropriate waste treatment technologies. An initial investigation was made of the nature of the organics in several waste-tank liquids. This report details the analysis of ORNL wastes

Predicting nitrogen and acidity effects on long-term dynamics of dissolved organic matter

OpenAIRE

Rowe, E.C.; Tipping, E.; Posch, M.; Oulehle, Filip; Cooper, D.M.; Jones, T.G.; Burden, A.; Hall, J.; Evans, C.D.

2014-01-01

Increases in dissolved organic carbon (DOC) fluxes may relate to changes in sulphur and nitrogen pollution. We integrated existing models of vegetation growth and soil organic matter turnover, acid-base dynamics, and organic matter mobility, to form the ‘MADOC’ model. After calibrating parameters governing interactions between pH and DOC dissolution using control treatments on two field experiments, MADOC reproduced responses of pH and DOC to additions of acidifying and alkalising solutions. ...

A mixing-model approach to quantifying sources of organic matter to salt marsh sediments

Science.gov (United States)

Bowles, K. M.; Meile, C. D.

2010-12-01

Salt marshes are highly productive ecosystems, where autochthonous production controls an intricate exchange of carbon and energy among organisms. The major sources of organic carbon to these systems include 1) autochthonous production by vascular plant matter, 2) import of allochthonous plant material, and 3) phytoplankton biomass. Quantifying the relative contribution of organic matter sources to a salt marsh is important for understanding the fate and transformation of organic carbon in these systems, which also impacts the timing and magnitude of carbon export to the coastal ocean. A common approach to quantify organic matter source contributions to mixtures is the use of linear mixing models. To estimate the relative contributions of endmember materials to total organic matter in the sediment, the problem is formulated as a constrained linear least-square problem. However, the type of data that is utilized in such mixing models, the uncertainties in endmember compositions and the temporal dynamics of non-conservative entitites can have varying affects on the results. Making use of a comprehensive data set that encompasses several endmember characteristics - including a yearlong degradation experiment - we study the impact of these factors on estimates of the origin of sedimentary organic carbon in a saltmarsh located in the SE United States. We first evaluate the sensitivity of linear mixing models to the type of data employed by analyzing a series of mixing models that utilize various combinations of parameters (i.e. endmember characteristics such as δ13COC, C/N ratios or lignin content). Next, we assess the importance of using more than the minimum number of parameters required to estimate endmember contributions to the total organic matter pool. Then, we quantify the impact of data uncertainty on the outcome of the analysis using Monte Carlo simulations and accounting for the uncertainty in endmember characteristics. Finally, as biogeochemical processes

Progress of organic matter degradation and maturity of compost produced in a large-scale composting facility.

Science.gov (United States)

Nakasaki, Kiyohiko; Marui, Taketoshi

2011-06-01

To monitor the progress of organic matter degradation in a large-scale composting facility, the percentage of organic matter degradation was determined by measuring CO(2) evolution during recomposting of compost samples withdrawn from the facility. The percentage of organic matter degradation was calculated as the ratio of the amount of CO(2) evolved from compost raw material to that evolved from each sample during recomposting in the laboratory composting apparatus. It was assumed that the difference in the cumulative emission of CO(2) between the compost raw material and a sample corresponds to the amount of CO( 2) evolved from the sample in the composting facility. Using this method, the changes in organic matter degradation during composting in practical large-scale composting facilities were estimated and it was found that the percentage of organic matter degradation increased more vigorously in the earlier stages than in the later stages of composting. The percentage of organic matter degradation finally reached 78 and 55% for the compost produced from garbage-animal manure mixture and distillery waste (shochu residue), respectively. It was thus ascertained that organic matter degradation progressed well in both composting facilities. Furthermore, by performing a plant growth assay, it was observed that the compost products of both the facilities did not inhibit seed germination and thus were useful in promoting plant growth.

Stabilization of dissolved organic matter by aluminium: A toxic effect or stabilization through precipitation?

NARCIS (Netherlands)

Scheel, T.; Jansen, B.; van Wijk, A.J.; Verstraten, J.M.; Kalbitz, K.

2008-01-01

Carbon mineralization in acidic forest soils can be retarded by large concentrations of aluminium (Al). However, it is still unclear whether Al reduces C mineralization by direct toxicity to microorganisms or by decreased bioavailability of organic matter (OM) because dissolved organic matter (DOM)

A Transformational Journey: Compositional Changes in Organic Matter during Desorption from Sediments

Science.gov (United States)

Matiasek, S. J.; Pellerin, B. A.; Spencer, R.; Bergamaschi, B. A.; Hernes, P.

2016-12-01

The release of organic matter (OM) from suspended particles via desorption is a critical component of OM cycling since dissolved OM (DOM) fuels aquatic ecosystems and is a precursor for disinfection by-products formation. This study assessed the elemental and molecular composition of DOM desorbed abiotically from sediments and soils of an irrigated agricultural watershed of northern California. Relative to mineral-bound OM, the released DOM was nitrogen-poor (lower carbon:nitrogen ratios) and depleted in amino acids and lignin phenols (lower carbon-normalized yields). Water-extracted DOM appeared substantially more degraded than its parent particulate OM with increased molar contributions of acidic amino acids, non-protein amino acids, and acidic lignin phenols, all molecular indicators of a more extensively processed OM pool. Desorption processes also significantly altered lignin compositional ratios which help distinguish vascular-plant sources of DOM. Specific optical parameters, including spectral slope, specific UV absorbance at 254 nm (SUVA254), and fluorescence index (FI), did not constitute useful proxies for the desorbed DOM pool, while absorption coefficients and fluorescence peak intensities were strongly correlated with extracted DOM concentrations and composition. This study highlights the profound impact of desorption on DOM composition which, if unaccounted for, could lead to misinterpretations of common biomarkers and optical proxies used to predict DOM sources and reactivity. Our findings suggest that sediments contribute a biogeochemically distinct source of DOM to surface waters, with potential impacts on aquatic health and drinking water quality.

Terrestrial dissolved organic matter distribution in the North Sea.

Science.gov (United States)

Painter, Stuart C; Lapworth, Dan J; Woodward, E Malcolm S; Kroeger, Silke; Evans, Chris D; Mayor, Daniel J; Sanders, Richard J

2018-07-15

The flow of terrestrial carbon to rivers and inland waters is a major term in the global carbon cycle. The organic fraction of this flux may be buried, remineralized or ultimately stored in the deep ocean. The latter can only occur if terrestrial organic carbon can pass through the coastal and estuarine filter, a process of unknown efficiency. Here, data are presented on the spatial distribution of terrestrial fluorescent and chromophoric dissolved organic matter (FDOM and CDOM, respectively) throughout the North Sea, which receives organic matter from multiple distinct sources. We use FDOM and CDOM as proxies for terrestrial dissolved organic matter (tDOM) to test the hypothesis that tDOM is quantitatively transferred through the North Sea to the open North Atlantic Ocean. Excitation emission matrix fluorescence and parallel factor analysis (EEM-PARAFAC) revealed a single terrestrial humic-like class of compounds whose distribution was restricted to the coastal margins and, via an inverse salinity relationship, to major riverine inputs. Two distinct sources of fluorescent humic-like material were observed associated with the combined outflows of the Rhine, Weser and Elbe rivers in the south-eastern North Sea and the Baltic Sea outflow to the eastern central North Sea. The flux of tDOM from the North Sea to the Atlantic Ocean appears insignificant, although tDOM export may occur through Norwegian coastal waters unsampled in our study. Our analysis suggests that the bulk of tDOM exported from the Northwest European and Scandinavian landmasses is buried or remineralized internally, with potential losses to the atmosphere. This interpretation implies that the residence time in estuarine and coastal systems exerts an important control over the fate of tDOM and needs to be considered when evaluating the role of terrestrial carbon losses in the global carbon cycle. Copyright © 2018 The Author(s). Published by Elsevier B.V. All rights reserved.

Colored dissolved organic matter in shallow estuaries: the effect of source on quantification

OpenAIRE

W. K. Oestreich; N. K. Ganju; J. W. Pohlman; S. E. Suttles

2015-01-01

Light availability is of primary importance to the ecological function of shallow estuaries. For example, benthic primary production by submerged aquatic vegetation is contingent upon light penetration to the seabed. A major component that attenuates light in estuaries is colored dissolved organic matter (CDOM). CDOM is often measured via a proxy, fluorescing dissolved organic matter (fDOM...

The fate or organic matter during planetary accretion - Preliminary studies of the organic chemistry of experimentally shocked Murchison meteorite

Science.gov (United States)

Tingle, Tracy N.; Tyburczy, James A.; Ahrens, Thomas J.; Becker, Christopher H.

1992-01-01

The fate of organic matter in carbonaceous meteorites during hypervelocity (1-2 km/sec) impacts is investigated using results of experiments in which three samples of the Murchison (CM2) carbonaceous chondrite were shocked to 19, 20, and 36 GPa and analyzed by highly sensitive thermal-desorption photoionization mass spectrometry (SALI). The thermal-desorptive SALI mass spectra of unshocked CM2 material revealed presence of indigenous aliphatic, aromatic, sulfur, and organosulfur compounds, and samples shocked to about 20 GPa showed little or no loss of organic matter. On the other hand, samples shocked to 36 GPa exhibited about 70 percent loss of organic material and a lower alkene/alkane ratio than did the starting material. The results suggest that it is unlikely that the indigenous organic matter in carbonaceous chondritelike planetesimals could have survived the impact on the earth in the later stages of earth's accretion.

Role of organic matter in the Proterozoic Oklo natural fission reactors, Gabon, Africa

International Nuclear Information System (INIS)

Nagy, B.; Rigali, M.J.; Gauthier-Lafaye, F.; Holliger, P.; Mossman, D.J.; Leventhal, J.S.

1993-01-01

Of the sixteen known Oklo and the Bangombe natural fission reactors (hydrothermally altered elastic sedimentary rocks that contain abundant uraninite and authigenic clay minerals), reactors 1 to 6 at Oklo contain only traces of organic matter, but the others are rich in organic substances. Reactors 7 to 9 are the subjects of this study. These organic-rich reactors may serve as time-tested analogues for anthropogenic nuclear-waste containment strategies. Organic matter helped to concentrate quantities of uranium sufficient to initiate the nuclear chain reactions. Liquid bitumen was generated from organic matter by hydrothermal reactions during nuclear criticality. The bitumen soon became a solid, consisting of polycyclic aromatic hydrocarbons and an intimate mixture of cryptocrystalline graphite, which enclosed and immobilized uraninite and the fission-generated isotopes entrapped in uraninite. This mechanism prevented major loss of uranium and fission products from the natural nuclear reactors for 1.2 b.y. 24 refs., 4 figs

Long – term evalutation of the organic matter balance and its relations to the organic C content in the topsoils in Ústí nad Orlicí district

Directory of Open Access Journals (Sweden)

Jiří Dostál

2009-01-01

Full Text Available Organic matter balance in the farms located in Ústí nad Orlicí district has been investigated since 1979. As a result, so called need of organic fertilisation, has been determined and the supply of the organic fertilisers to soils, e.g. farmyard manure, slurries and also straw and green manure has been monitored over the whole time period. About 45 % of the arable land area in the district has been monitored.In addition to the organic matter balance, we determined several soil organic matter characteristics in soil samples (organic C, N and S contents, inert and decomposable C content, hot water soluble C content, hydrophobicity index calculated from the DRIFT spectrometry, available P, K, Ca and Mg contents and pH.The relationships between the organic matter supply with supplemental sources organic fertilisers and all the selected soil organic matter characteristics were statistically significant. Significant correlations were also found for the relationships between the organic matter need and all the selected soil organic matter characteristics.

White matter microstructural organization and gait stability in older adults

Directory of Open Access Journals (Sweden)

Sjoerd M. Bruijn

2014-06-01

Full Text Available Understanding age-related decline in gait stability and the role of alterations in brain structure is crucial. Here, we studied the relationship between white matter microstructural organization using Diffusion Tensor Imaging (DTI and advanced gait stability measures in 15 healthy young adults (range 18-30 years and 25 healthy older adults (range 62-82 years.Among the different gait stability measures, only stride time and the maximum Lyapunov exponent (which quantifies how well participants are able to attenuate small perturbations were found to decline with age. White matter microstructural organization (FA was lower throughout the brain in older adults. We found a strong correlation between FA in the left anterior thalamic radiation and left corticospinal tract on the one hand, and step width and safety margin (indicative of how close participants are to falling over on the other. These findings suggest that white matter FA in tracts connecting subcortical and prefrontal areas is associated with the implementation of an effective stabilization strategy during gait.

SOMPROF: A vertically explicit soil organic matter model

NARCIS (Netherlands)

Braakhekke, M.C.; Beer, M.; Hoosbeek, M.R.; Kruijt, B.; Kabat, P.

2011-01-01

Most current soil organic matter (SOM) models represent the soil as a bulk without specification of the vertical distribution of SOM in the soil profile. However, the vertical SOM profile may be of great importance for soil carbon cycling, both on short (hours to years) time scale, due to

Influence of Soil Organic Matter Content on Abundance and Biomass of Earthworm (Oligochaeta: Lumbricidae Populations

Directory of Open Access Journals (Sweden)

Hristo Valchovski

2016-06-01

Full Text Available The current study explores the influence of soil organic matter content on abundance and biomass of earthworm communities. The observation was carried out on three type of soils: PellicVertisols (very fine texture, Cromi-Vertic Luvisols (fine texture and Calcaric Fluvisols (mediumtexture from the Balkan Peninsula (Bulgaria. The field experiment was provided on uncultivatedplots. In the studied area earthworm fauna comprises of four species: Aporrectodea rosea,Aporrectodea caliginosa, Lumbricus terrestris and Octolasion lacteum. We found peregrine lumbricidtaxa, which are widely distributed in European soils. Our study demonstrated that soil organicmatter has a positive effect on lumbricid populations. It was revealed that augmentation of soilorganic matter favours characteristics of earthworm communities. The soil organic matter contentand earthworm abundance are in strong positive correlation (r > 0.981. The same relationship wasrevealed between the biomass of lumbricid fauna and amount of soil organic matter (r > 0.987. Insum, the soil organic matter could be used as an indicator for earthworm communities inuncultivated soils.

Optical Algorithms at Satellite Wavelengths for Total Suspended Matter in Tropical Coastal Waters

Directory of Open Access Journals (Sweden)

Alain Muñoz-Caravaca

2008-07-01

Full Text Available Is it possible to derive accurately Total Suspended Matter concentration or its proxy, turbidity, from remote sensing data in tropical coastal lagoon waters? To investigate this question, hyperspectral remote sensing reflectance, turbidity and chlorophyll pigment concentration were measured in three coral reef lagoons. The three sites enabled us to get data over very diverse environments: oligotrophic and sediment-poor waters in the southwest lagoon of New Caledonia, eutrophic waters in the Cienfuegos Bay (Cuba, and sediment-rich waters in the Laucala Bay (Fiji. In this paper, optical algorithms for turbidity are presented per site based on 113 stations in New Caledonia, 24 stations in Cuba and 56 stations in Fiji. Empirical algorithms are tested at satellite wavebands useful to coastal applications. Global algorithms are also derived for the merged data set (193 stations. The performances of global and local regression algorithms are compared. The best one-band algorithms on all the measurements are obtained at 681 nm using either a polynomial or a power model. The best two-band algorithms are obtained with R412/R620, R443/R670 and R510/R681. Two three-band algorithms based on Rrs620.Rrs681/Rrs412 and Rrs620.Rrs681/Rrs510 also give fair regression statistics. Finally, we propose a global algorithm based on one or three bands: turbidity is first calculated from Rrs681 and then, if < 1 FTU, it is recalculated using an algorithm based on Rrs620.Rrs681/Rrs412. On our data set, this algorithm is suitable for the 0.2-25 FTU turbidity range and for the three sites sampled (mean bias: 3.6 %, rms: 35%, mean quadratic error: 1.4 FTU. This shows that defining global empirical turbidity algorithms in tropical coastal waters is at reach.

Optical Algorithms at Satellite Wavelengths for Total Suspended Matter in Tropical Coastal Waters

Science.gov (United States)

Ouillon, Sylvain; Douillet, Pascal; Petrenko, Anne; Neveux, Jacques; Dupouy, Cécile; Froidefond, Jean-Marie; Andréfouët, Serge; Muñoz-Caravaca, Alain

2008-01-01

Is it possible to derive accurately Total Suspended Matter concentration or its proxy, turbidity, from remote sensing data in tropical coastal lagoon waters? To investigate this question, hyperspectral remote sensing reflectance, turbidity and chlorophyll pigment concentration were measured in three coral reef lagoons. The three sites enabled us to get data over very diverse environments: oligotrophic and sediment-poor waters in the southwest lagoon of New Caledonia, eutrophic waters in the Cienfuegos Bay (Cuba), and sediment-rich waters in the Laucala Bay (Fiji). In this paper, optical algorithms for turbidity are presented per site based on 113 stations in New Caledonia, 24 stations in Cuba and 56 stations in Fiji. Empirical algorithms are tested at satellite wavebands useful to coastal applications. Global algorithms are also derived for the merged data set (193 stations). The performances of global and local regression algorithms are compared. The best one-band algorithms on all the measurements are obtained at 681 nm using either a polynomial or a power model. The best two-band algorithms are obtained with R412/R620, R443/R670 and R510/R681. Two three-band algorithms based on Rrs620.Rrs681/Rrs412 and Rrs620.Rrs681/Rrs510 also give fair regression statistics. Finally, we propose a global algorithm based on one or three bands: turbidity is first calculated from Rrs681 and then, if < 1 FTU, it is recalculated using an algorithm based on Rrs620.Rrs681/Rrs412. On our data set, this algorithm is suitable for the 0.2-25 FTU turbidity range and for the three sites sampled (mean bias: 3.6 %, rms: 35%, mean quadratic error: 1.4 FTU). This shows that defining global empirical turbidity algorithms in tropical coastal waters is at reach. PMID:27879929

Measurements of total suspended matter - How does salinity and the amount of rinse water influence the results; Maetning av totalt suspenderat material - Hur paaverkar salthalt och maengden skoeljvatten resultatet

Energy Technology Data Exchange (ETDEWEB)

Hall, Bjoern (Bjoern Hall, Miljoe och Foerbraenningskemi, Onsala (Sweden))

2010-03-15

Under regulations for incineration of waste NFS 2002:28 total suspended matter (tsm) in wastewater from incineration plants are analyzed by daily sampling measurement or by representative flow-proportional 24-hour test. It has been shown that many plants that analyzes the suspended matter according to EN 872:2005 are having trouble keeping their conditions for suspended solids constant. This applies mainly to plants rated for a high chloride content in the closing process. Waste Sweden has for years drawn attention to this problem and have with a joint working group with representatives from the Swedish waste incineration plants tried to obtain a better understanding of this phenomenon. The basic question is whether the water from the facilities in question really contain high levels of tsm or if there is something else behind the observed concentrations. The results from this study suggest that the most important factor is the salinity and the amount of rinse water used in the analysis. Under the standard, all samples are washed with 2 x 20 ml of water. If salinity exceeds 1000 mg/l, a further 3 x 50 ml used. How this process is this implemented in practice varies from laboratory to laboratory and there is no laboratory that regularly measure the salinity of the sample. It is not specified especially when submitting the sample uses most of the labs normal rinse water of 2 x 20 ml. The findings also indicate that the samples with very high salinities the standard stipulated 190 mls is not enough. This would likely lead to that further rinse water is needed. In order to establish safe Several measurements would be needed to confirm this assumption. A relatively simple way to obtain an idea of the salinity of the test is to measure its conductivity. Accordingly, this could be a first step on to get a more consistent performance than is the case at present

Organic matter processing by microbial communities throughout the Atlantic water column as revealed by metaproteomics

DEFF Research Database (Denmark)

Bergauer, Kristin; Fernandez-Guerra, Antonio; Garcia, Juan A L

2018-01-01

The phylogenetic composition of the heterotrophic microbial community is depth stratified in the oceanic water column down to abyssopelagic layers. In the layers below the euphotic zone, it has been suggested that heterotrophic microbes rely largely on solubilized particulate organic matter...... as a carbon and energy source rather than on dissolved organic matter. To decipher whether changes in the phylogenetic composition with depth are reflected in changes in the bacterial and archaeal transporter proteins, we generated an extensive metaproteomic and metagenomic dataset of microbial communities...... collected from 100- to 5,000-m depth in the Atlantic Ocean. By identifying which compounds of the organic matter pool are absorbed, transported, and incorporated into microbial cells, intriguing insights into organic matter transformation in the deep ocean emerged. On average, solute transporters accounted...

Peatland Organic Matter Chemistry Trends Over a Global Latitudinal Gradient

Science.gov (United States)

Verbeke, B. A.; Hodgkins, S. B.; Carson, M. A.; Lamit, L. J.; Lilleskov, E.; Chanton, J.

2017-12-01

Peatlands contain a significant amount of the global soil carbon, and the climate feedback of carbon cycling within these peatland systems is still relatively unknown. Organic matter composition of peatlands plays a major role in determining carbon storage, and while high latitude peatlands seem to be the most sensitive to climate change, a global picture of peat organic matter chemistry is required to improve predictions and models of greenhouse gas emissions fueled by peatland decomposition. The objective of this research is to test the hypothesis that carbohydrate content of peatlands near the equator will be lower than high latitude peatlands, while aromatic content will be higher. As a part of the Global Peatland Microbiome Project (GPMP), around 2000 samples of peat from 10 to 70 cm across a latitudinal gradient of 79 N to 53 S were measured with Fourier transform infrared spectroscopy (FTIR) to examine the organic matter functional groups of peat. Carbohydrate and aromatic content, as determined by FTIR, are useful proxies of decomposition potential and recalcitrance, respectively. We found a highly significant relationship between carbohydrate and aromatic content, latitude, and depth. Carbohydrate content of high latitude sites were significantly greater than at sites near the equator, in contrast to aromatic content which showed the opposite trend. It is also clear that carbohydrate content decreases with depth while aromatic content increases with depth. Higher carbohydrate content at higher latitudes indicates a greater potential for lability and resultant mineralization to form the greenhouse gases, carbon dioxide and methane, whereas the composition of low latitude peatlands is consistent with their apparent stability. We speculate that the combination of low carbohydrates and high aromatics at warmer locations near the equator could foreshadow the organic matter composition of high latitude peat transitioning to a more recalcitrant form with a

Role of sedimentary organic matter in bacterial sulfate reduction: the G model tested

International Nuclear Information System (INIS)

Westrich, J.T.; Berner, R.A.

1984-01-01

Laboratory study of the bacterial decomposition of Long Island Sound plankton in oxygenated seawater over a period of 2 years shows that the organic material undergoes decomposition via first-order kinetics and can be divided into two decomposable fractions, of considerably different reactivity, and a nonmetabolized fraction. This planktonic material, after undergoing varying degrees of oxic degradation, was added in the laboratory to anoxic sediment taken from a depth of 1 m at the NWC site of Long Island Sound and the rate of bacterial sulfate reduction in the sediment measured by the 35 S radiotracer technique. The stimulated rate of sulfate reduction was in direct proportion to the amount of planktonic carbon added. This provides direct confirmation of the first-order decomposition, or G model, for marine sediments and proves that the in situ rate of sulfate reduction is organic-matter limited. Slower sulfate reduction rates resulted when oxically degraded plankton rather than fresh plankton was added, and the results confirm the presence of the same two fractions of organic matter deduced from the oxic degradation studies. Near-surface Long Island Sound sediment, which already contains abundant readily decomposable organic matter, was also subjected to anoxic decomposition by bacterial sulfate reduction. The decrease in sulfate reduction rate with time parallels decreases in the amount of organic matter, and these results also indicate the presence of two fractions of organic carbon of distinctly different reactivity. From plots of the log of reduction rate vs. time two first-order rate constants were obtained that agree well with those derived from the plankton addition experiment. Together, the two experiments confirm the use of a simple multi-first-order rate law for organic matter decomposition in marine sediments

Aquatic Organic Matter Fluorescence - from phenomenon to application

Science.gov (United States)

Reynolds, Darren

2014-05-01

The use of fluorescence to quantify and characterise aquatic organic matter in river, ocean, ground water and drinking and waste waters has come along way since its discovery as a phenomenon in the early 20th century. For example, there are over 100 papers published each year in international peer reviewed journals, an order of magnitude increase since a decade ago (see Figure taken from ISI database from 1989 to 2007 for publications in the fields of river water and waste water). Since then it has been extensively used as a research tool since the 1990's by scientists and is currently used for a wide variety of applications within a number of sectors. Universities, organisations and companies that research into aquatic organic matter have either recently readily use appropriate fluorescence based techniques and instrumentation. In industry and government, the technology is being taken up by environmental regulators and water and wastewater companies. This keynote presentation will give an overview of aquatic organic matter fluorescence from its conception as a phenomenon through to its current use in a variety of emerging applications within the sectors concerned with understanding, managing and monitoring the aquatic environment. About the Speaker Darren Reynolds pioneered the use of fluorescence spectroscopy for the analysis of wastewaters in the 1990's. He currently leads a research group within the Centre for Research in Biosciences and sits on the Scientific Advisory Board for the Institute of Bio-Sensing Technology at the University of the West of England, Bristol. He is a multidisciplinary scientist concerned with the development of technology platforms for applications in the fields of environment/agri-food and health. His current research interests include the development of optical technologies and techniques for environmental and biological sensing and bio-prospecting applications. He is currently involved in the development and use of synthetic biology

Assessment of the unidentified organic matter fraction in fogwater using fluorescence spectroscopy

Science.gov (United States)

Valsaraj, K.; Birdwell, J.

2010-07-01

Dissolved organic matter (DOM) in fogwaters from southeastern Louisiana and central-eastern China has been characterized using excitation-emission matrix (EEM) fluorescence spectroscopy. The results demonstrate that fluorescence spectroscopy can be used to obtain a qualitative assessment of the large fraction of fogwater organic carbon (~40 - 80% by weight) that cannot be identified in terms of specific chemical compounds. The method has the principle advantage that it can be applied at natural abundance concentrations, thus eliminating the need for large sample volumes required to isolate DOM for characterization by other spectroscopic (NMR, FTIR) and chemical (elemental) analyses. It was anticipated that the fogwater organic matter fluorescence spectra would resemble those of surface and rain waters, containing peaks indicative of both humic substances and fluorescent amino acids. Humic- and protein-like fluorophores were observed in the fogwater spectra and fluorescence-derived indices had values comparable to other natural waters. Biological character (intensity of tyrosine and tryptophan peaks) was found to increase with organic carbon concentration. Fogwater organic matter appears to contain a mixture of terrestrially- and microbially-derived material. The fluorescence results show that most of the unidentified fogwater organic carbon can be represented by humic-like and biologically-derived substances similar to those present in other aquatic systems.

Elemental Spatiotemporal Variations of Total Suspended Particles in Jeddah City

OpenAIRE

Kadi, Mohammad W.

2014-01-01

Elements associated with total suspended particulate matter (TSP) in Jeddah city were determined. Using high-volume samplers, TSP samples were simultaneously collected over a one-year period from seven sampling sites. Samples were analyzed for Al, Ba, Ca, Cu, Mg, Fe, Mn, Zn, Ti, V, Cr, Co, Ni, As, and Sr. Results revealed great dependence of element contents on spatial and temporal variations. Two sites characterized by busy roads, workshops, heavy population, and heavy trucking have high lev...

Properties and reactivity of aquatic organic matter from an Amazonian floodplain system

Science.gov (United States)

Perez, M. A. P.; Benedetti, M. F.; Moreira-Turcq, P.

2009-04-01

The aim of this study was to characterize the nature of the bulk dissolved organic matter (DOM) in different types of environments in the Amazon River-floodplain system and determine the importance of two different fractions of dissolved organic matter onto adsorption processes that occurs through the transport of organic matter in the Amazon Basin. Seven samples were collected in the Amazon River - "Lago Grande de Curuai" floodplain system, in rising water levels cruise (March 2006). The samples were taken in the Amazon main stem, in white and black floodplain waters, and in the middle of a phytoplaktonic bloom. The bulk, dissolved (i.e. acid-base titration) were characterized for these fractions. Adsorption experiments onto mineral phase from de surface sediment of the Curuai floodplain lake (rich in smectite and kaolinite) were realized with HPO and TPH fractions. The OC concentrations in the natural organic matter (Bulk and < 0.22 micrometer fractions) varied between 3.7-5.7 mg/L. The OC and TN concentrations varied between 510 - 528 mg C/g in the HPO fraction, and 408 - 462 mg C/g in the TPH compounds and between 14.3 - 17.6 mg N/g (HPO), and 22.1 - 30.0 mg N/g (TPH). The molecular weight of both fractions (HPO and TPH) didn't present significant variation. Both fractions presented high aromaticity and they were rich in carboxylic groups, although smaller values are systematically reported for the HPO fractions. The OM of the main stem was the most adsorbed, followed by the white water lake, the phytoplanktonic bloom, and black water lake sample. These results helped us to strengthen the hypothesis that the organic matter carried from the river and sediment in the floodplain is closely associated with mineral phase.

Global effects of agriculture on fluvial dissolved organic matter

DEFF Research Database (Denmark)

Graeber, Daniel; Boëchat, Iola; Encina, Francisco

2015-01-01

Agricultural land covers approximately 40% of Earth’s land surface and affects hydromorphological, biogeochemical and ecological characteristics of fluvial networks. In the northern temperate region, agriculture also strongly affects the amount and molecular composition of dissolved organic matter...

Organic speciation of size-segregated atmospheric particulate matter

Science.gov (United States)

Tremblay, Raphael

Particle size and composition are key factors controlling the impacts of particulate matter (PM) on human health and the environment. A comprehensive method to characterize size-segregated PM organic content was developed, and evaluated during two field campaigns. Size-segregated particles were collected using a cascade impactor (Micro-Orifice Uniform Deposit Impactor) and a PM2.5 large volume sampler. A series of alkanes and polycyclic aromatic hydrocarbons (PAHs) were solvent extracted and quantified using a gas chromatograph coupled with a mass spectrometer (GC/MS). Large volume injections were performed using a programmable temperature vaporization (PTV) inlet to lower detection limits. The developed analysis method was evaluated during the 2001 and 2002 Intercomparison Exercise Program on Organic Contaminants in PM2.5 Air Particulate Matter led by the US National Institute of Standards and Technology (NIST). Ambient samples were collected in May 2002 as part of the Tampa Bay Regional Atmospheric Chemistry Experiment (BRACE) in Florida, USA and in July and August 2004 as part of the New England Air Quality Study - Intercontinental Transport and Chemical Transformation (NEAQS - ITCT) in New Hampshire, USA. Morphology of the collected particles was studied using scanning electron microscopy (SEM). Smaller particles (one micrometer or less) appeared to consist of solid cores surrounded by a liquid layer which is consistent with combustion particles and also possibly with particles formed and/or coated by secondary material like sulfate, nitrate and secondary organic aerosols. Source apportionment studies demonstrated the importance of stationary sources on the organic particulate matter observed at these two rural sites. Coal burning and biomass burning were found to be responsible for a large part of the observed PAHs during the field campaigns. Most of the measured PAHs were concentrated in particles smaller than one micrometer and linked to combustion sources

Archaeal remains dominate marine organic matter from the early Albian oceanic anoxic event 1b

DEFF Research Database (Denmark)

Kuypers, M.M.M.; Blokker, P.; Hopmans, E.C.

2002-01-01

The sources for both soluble and insoluble organic matter of the early Albian (∼112 Myr) oceanic anoxic event (OAE) 1b black shales of the Ocean Drilling Program (ODP) site 1049C (North Atlantic Ocean off the coast of Florida) and the Ravel section of the Southeast France Basin (SEFB) were...... in C/C ratios was used to estimate that up to ∼40% of the organic matter of the SEFB and up to ∼80% of the organic matter of ODP site 1049C preserved in the black shales is derived from archaea. Furthermore, it is shown that, even though there are apparent similarities (high organic carbon (OC) content......, distinct lamination, C-enrichment of OC) between the black shales of OAE1b and the Cenomanian/Turonian (∼94 Myr) OAE, the origin of the organic matter (archaeal versus phytoplanktonic) and causes for C-enrichment of OC are completely different....

Sea cucumbers reduce chromophoric dissolved organic matter in aquaculture tanks.

Science.gov (United States)

Sadeghi-Nassaj, Seyed Mohammad; Catalá, Teresa S; Álvarez, Pedro A; Reche, Isabel

2018-01-01

Mono-specific aquaculture effluents contain high concentrations of nutrients and organic matter, which affect negatively the water quality of the recipient ecosystems. A fundamental feature of water quality is its transparency. The fraction of dissolved organic matter that absorbs light is named chromophoric dissolved organic matter (CDOM). A sustainable alternative to mono-specific aquaculture is the multitrophic aquaculture that includes species trophically complementary named "extractive" species that uptake the waste byproducts. Sea cucumbers are recognized as efficient extractive species due to the consumption of particulate organic matter (POM). However, the effects of sea cucumbers on CDOM are still unknown. During more than one year, we monitored CDOM in two big-volume tanks with different trophic structure. One of the tanks (-holothurian) only contained around 810 individuals of Anemonia sulcata , whereas the other tank (+holothurian) also included 90 individuals of Holothuria tubulosa and Holothuria forskali . We routinely analyzed CDOM absorption spectra and determined quantitative (absorption coefficients at 325 nm) and qualitative (spectral slopes) optical parameters in the inlet waters, within the tanks, and in their corresponding effluents. To confirm the time-series results, we also performed three experiments. Each experiment consisted of two treatments: +holothurians (+H) and -holothurians (-H). We set up three +H tanks with 80 individuals of A. sulcata and 10 individuals of H. tubulosa in each tank and four -H tanks that contained only 80 individuals of A. sulcata . In the time-series, absorption coefficients at 325 nm ( a 325 ) and spectral slopes from 275 to 295 nm ( S 275-295 ) were significantly lower in the effluent of the +holothurian tank (average: 0.33 m -1 and 16 µm -1 , respectively) than in the effluent of the -holothurian tank (average: 0.69 m -1 and 34 µm -1 , respectively), the former being similar to those found in the inlet

Optical properties of size fractions of suspended particulate matter in littoral waters of Québec

Science.gov (United States)

Mohammadpour, Gholamreza; Gagné, Jean-Pierre; Larouche, Pierre; Montes-Hugo, Martin A.

2017-11-01

Mass-specific absorption (ai∗(λ)) and scattering (bi∗(λ)) coefficients were derived for four size fractions (i = 0.2-0.4, 0.4-0.7, 0.7-10, and > 10 µm, λ = wavelength in nm) of suspended particulate matter (SPM) and with samples obtained from surface waters (i.e., 0-2 m depth) of the Saint Lawrence Estuary and Saguenay Fjord (SLE-SF) during June of 2013. For the visible-near-infrared spectral range (i.e., λ = 400-710 nm), mass-specific absorption coefficients of total SPM (i.e., particulates > 0.2 µm) (hereafter aSPM∗) had low values (e.g., 0.05 m2 g-1 at λ = 440 nm) corresponded with locations of the upper estuary and SF where particulates were mineral-rich and/or their mean diameter was relatively small. The variability of two optical proxies (the spectral slope of particulate beam attenuation coefficient and the mass-specific particulate absorption coefficient, hereafter γ and Svis, respectively) with respect to changes in particle size distribution (PSD) and chemical composition was also examined. The slope of the PSD was correlated with bi∗(550) (Spearman rank correlation coefficient ρs up to 0.37) and ai∗(440) estimates (ρs up to 0.32) in a comparable way. Conversely, the contribution of particulate inorganic matter to total mass of SPM (FSPMPIM) had a stronger correlation with ai∗ coefficients at a wavelength of 440 nm (ρs up to 0.50). The magnitude of γ was positively related to FSPMi or the contribution of size fraction i to the total mass of SPM (ρs up to 0.53 for i = 0.2-0.4 µm). Also, the relation between γ and FSPMPIM variability was secondary (ρs = -0.34, P > 0.05). Lastly, the magnitude of Svis was inversely correlated with aSPM∗(440) (ρs = -0.55, P = 0.04) and FSPMPIM (ρs = -0.62, P = 0.018) in sampling locations with a larger marine influence (i.e., lower estuary).

Biogeneration of chromophoric dissolved organic matter by bacteria and krill in the southern ocean

OpenAIRE

Ortega-Retuerta, E.; Frazer, Thomas K.; Duarte, Carlos M.; Ruiz-Halpern, Sergio; Tovar-Sánchez, Antonio; Arrieta López de Uralde, Jesús M.; Reche, Isabel

2009-01-01

Chromophoric dissolved organic matter (CDOM), the optically active fraction of dissolved organic matter, is primarily generated by pelagic organisms in the open ocean. In this study, we experimentally determined the quantity and spectral quality of CDOM generated by bacterioplankton using two different substrates (with and without photoproducts) and by Antarctic krill Euphausia superba and evaluated their potential contributions to CDOM dynamics in the peninsular region of the Southern Ocean....

Characterization and source identification of organic matter in view of land uses and heavy rainfall in the Lake Shihwa, Korea

International Nuclear Information System (INIS)

Lee, Yeonjung; Hur, Jin; Shin, Kyung-Hoon

2014-01-01

Highlights: • Organic matter derived from industrial area showed high biodegradability. • Organic matter transported from rural area was of refractory nature. • Autochthonous organic matter dominated in lake during the dry season. • Contributions of organic source by industrial and rural area increased at rainy season. - Abstract: The characteristics and sources of organic matter in water of the Lake Shihwa, which receives inputs from rural, urban, and industrial areas, were evaluated by examining the biodegradable organic carbon concentration, fluorescence spectra, and carbon and nitrogen isotope ratios, especially during rainy season and dry season. The organic matter transported from rural areas was of refractory nature, while that of industrial origin decomposed rapidly. As compared to the dry season, the organic matter in the rainy season was characterized by a reduced labile fraction. During the dry season, the autochthonous organic matter dominated in the lake, however, the contributions of allochthonous organic sources by industrial and rural areas significantly increased at rainy season. This investigation revealed that the transport of organic matter of anthropogenic origin to the Lake Shihwa was mainly influenced by heavy rainfall. Moreover, each anthropogenic source could differently influence the occurrence of organic matter in water of the Lake Shihwa

Determination and distribution of elements in suspended matter and bottom sediments from the estuaries of the Sea of Japan, the East China Sea, the South China Sea and the Bering Sea

International Nuclear Information System (INIS)

Kolesov, G.M.; Anikiev, V.V.

1997-01-01

Some aspects of sample analysis (for example, sampling, sample preparing, experimental conductions) from estuaries zones of the west part of Pacific shore have been discussed. The content of elements with different physico-chemical and geological properties in the water samples, suspended matter, bottom sediments, plankton and aerosols have been studied by the methods of neutron activation analysis, X-ray fluorescence and also atomic emission (with ICP) and atomic absorption. Some peculiarities of their distribution and accumulation have been revealed. (author)

Evidence of molybdenum association with particulate organic matter under sulfidic conditions

DEFF Research Database (Denmark)

Dahl, Tais Wittchen; Chappaz, A.; Hoek, Joost

2017-01-01

, consisting of mainly Mo(IV)-sulfide compounds with molecular structures similar to Mo enzymes and to those found in natural euxinic sediments. Therefore, we propose that Mo removal in natural sulfidic waters can proceed via a non-Fe-assisted pathway that requires particulate organic matter (dead or living......The geochemical behavior of molybdenum (Mo) in the oceans is closely linked to the presence of sulfide species in anoxic environments, where Fe availability may play a key role in the Mo scavenging. Here, we show that Mo(VI) is reduced in the presence of particulate organic matter (represented...

[Studies on nitrogen, phosphorus and organic matter in ponds around Chaohu Lake].

Science.gov (United States)

Sun, Qing-ye; Ma, Xiu-ling; Yang, Gui-de; Chen, Zheng; Wu, Hong-lin; Xuan, Huai-xiang

2010-07-01

There are a lot of ponds around Chaohu Lake. According to location and runoff supply of ponds, the ponds are divided into three types: ponds inner vellage (PIV), ponds adjacent vellage (PAV) and ponds outer vellage (POV). The samples of water and sediment were collected from 136 ponds around Chaohu Lake and the contents of nitrogen, phosphorus and organic matter in water and sediments were analyzed in this study. The results showed that mean contents of total nitrogen (TN), NH4+ -N, NO3- -N, NO2- -N, total phosphorus (TP), soluble PO4(3-) -P and COD were 2.53, 0.65, 0.18, 0.02, 0.97, 0.38 and 51.58 mg x L(-1) in pond water, respectively; and mean contents of TN, NH4+ -N, NO3- -N, NO2- -N, TP, inorganic phosphorus (IP), organic phosphorus (OP) and loss of ignition (LOI) in pond sediment were 1575.36, 35.73, 13.30, 2.88, 933.19, 490.14, 414.75 mg x kg(-1) and 5.44%, respectively. The ponds of more than 90% presented eutrophication in the contents of total nitrogen and phosphorus in water. The contents of TN and NH4+ -N in water and sediment of PIV were significantly higher than that of POV. And the contents of inorganic nitrogen in pond water and sediment displayed a following order: NH4+ -N > NO3- -N > NO2- -N. Data analysis indicated that there was a significantly positive correlation between organic matter and total nitrogen and phosphorus in water and sediment. The nitrogen, phosphorus and organic matter in ponds mainly sourced farmlands and village land surface. The contents of nitrogen, phosphorus and organic matter in ponds were affected by location and runoff supply of ponds. By retaining nitrogen, phosphorus and organic matter in runoff, the ponds can effectively decrease nutrient content into Chaohu Lake.

Concentrations of trace elements and compounds in the airborne suspended particulate matter in Cleveland, Ohio, from August 1971 to August 1972 and their dependence on wind direction: Complete data listing and concentration roses

Science.gov (United States)

King, R. B.; Neustadter, H. E.

1976-01-01

Concentrations of 75 chemical constituents in the airborne particulate matter were measured in Cleveland, Ohio during 1971 and 1972. Daily values, maxima, geometric means and their standard deviations covering a 1-year period (45 to 50 sampling days) at each of 16 sites are presented on microfiche for 60 elements, and for a lesser number of days for 10 polycyclic aromatic hydrocarbon compounds (PAH), the aliphatic hydrocarbon compounds (AH) as a group and carbon. In addition, concentration roses showing directional properties are presented for 39 elements, 10 PAH and the AH as a group. The elements (except carbon) are shown both in terms of concentration and percentage of the suspended particulate matter.

Stabilization of organic matter in the raised-bed soils of tidal swamplands is influenced by the types and the amounts of organic matter application

Directory of Open Access Journals (Sweden)

A R Saidy

2015-05-01

Full Text Available Farmers in tidal swamplands annually added organic matter (OM onto the raised beds to maintain organic matter contents and thereby maintain soil productivity of the raised beds. This experiment aimed to study the influence of the types and the amounts of OM on the stabilization of organic matter in the raised-bed soils. Four types of OM: rice straw, eceng gondok (Eichornia crassipes, purun tikus  (Eleocharis dulcis and mixed  rice straw-eceng gondok were added to a 27-year raised bed soil with 4 different rates: 0, 0.5, 1.0 and 2.0  of maximum sorption capacity (Qmax, and the OM stabilization was quantified after 10 weeks of OM addition.  Results of this study showed with the exception of rice straw, OM addition to soil resulted in increases in the mineralization of soil OM thereby inducing priming effect. Addition of rice straw at rate of 0.5 of Qmax resulted in stabilization of 46% added OM, while only 30% and 37% of added OM was stabilized when OM was added to soils at rates of 1.0 and 2.0 Qmax, respectively.  This study showed that the stabilization of OM in raised bed soils were influenced by the chemical composition of OM and the amount of added OM.

Stabilization of organic matter in the raised-bed soils of tidal swamplands is influenced by the types and the amounts of organic matter application

Directory of Open Access Journals (Sweden)

A R Saidy

2015-03-01

Full Text Available Farmers in tidal swamplands annually added organic matter (OM onto the raised beds to maintain organic matter contents and thereby maintain soil productivity of the raised beds. This experiment aimed to study the influence of the types and the amounts of OM on the stabilization of organic matter in the raised-bed soils. Four types of OM: rice straw, eceng gondok (Eichornia crassipes, purun tikus  (Eleocharis dulcis and mixed  rice straw-eceng gondok were added to a 27-year raised bed soil with 4 different rates: 0, 0.5, 1.0 and 2.0  of maximum sorption capacity (Qmax, and the OM stabilization was quantified after 10 weeks of OM addition.  Results of this study showed with the exception of rice straw, OM addition to soil resulted in increases in the mineralization of soil OM thereby inducing priming effect. Addition of rice straw at rate of 0.5 of Qmax resulted in stabilization of 46% added OM, while only 30% and 37% of added OM was stabilized when OM was added to soils at rates of 1.0 and 2.0 Qmax, respectively.  This study showed that the stabilization of OM in raised bed soils were influenced by the chemical composition of OM and the amount of added OM.

Distribution and behavior of radionuclides in the coastal ecosystem in Rokkasho Village

International Nuclear Information System (INIS)

Kondo, Kunio; Kawabata, Hitoshi; Ueda, Shinji; Hasegawa, Hidenao; Inaba, Jiro

2001-01-01

The aim of the present study was to elucidate, through both field studies and laboratory experiments, the mechanism for the elution of radionuclides and other materials from suspended organic matter that accompanies the decomposition of organic matter, consisting mainly of phytoplankton, in the coastal sea region off Rokkasho Village. The effect of water temperature on the decomposition rate of organic matter suspended in seawater was investigated in laboratory experiments. The results demonstrated that the decomposition process was divided into two steps for each of the items of dry weight (SS), particulate organic carbon (POC), and particulate organic nitrogen (PON). The first step in decomposition progressed rapidly over several days. The second step of decomposition occurred at a slower rate than the first step. The decomposition rate of organic material was found to be strongly dependent on temperature, with decomposition progressing faster the higher the temperature. The amounts of Mn, Zn, Cu, Pb, Sn, Ni, Be, V, Ti, Ba, Cr, Sr, and the radionuclides 232 Th and 238 Ur eluted from organic matter by decomposition (30 days) of suspended organic matter were in the range of 31-72% of the amounts contained in the organic matter. (author)

Observed effects of soil organic matter content on the microwave emissivity of soils

International Nuclear Information System (INIS)

O'Neill, P.E.; Jackson, T.J.

1990-01-01

In order to determine the significance of organic matter content on the microwave emissivity of soils when estimating soil moisture, a series of field experiments were conducted in which 1.4 GHz microwave emissivity data were collected over test plots of sandy loam soil with different organic matter levels (1.8%, 4.0%, and 6.1%) for a range of soil moisture values. Analyses of the observed data showed only minor variation in microwave emissivity due to a change in organic matter content at a given moisture level for soils with similar texture and structure. Predictions of microwave emissivity made using a dielectric model for aggregated soils exhibited the same trends and type of response as the measured data when adjusted values for the input parameters were utilized

Influence of microorganism content in suspended particles on the particle–water partitioning of mercury in semi-enclosed coastal waters

International Nuclear Information System (INIS)

Jang, Jiyi; Kim, Hyunji; Han, Seunghee

2014-01-01

It is known that particle scavenging of mercury (Hg) can be affected by the abundance of particulate organic matter in coastal waters. However, the role of living organic particles in Hg scavenging is not yet completely understood. In this study, we hypothesized that an abundance of living organic particles (i.e., phytoplankton and bacteria) would influence the particle–water partitioning of Hg in coastal waters. Surface seawater samples were collected from eight stations in Gwangyang Bay, Korea, in three seasons (November 2009, April 2010, and October 2010) for the determination of concentrations of suspended particulate matter (including chlorophyll-a and bacteria), and Hg in unfiltered and filtered waters. We found that more Hg partitioned toward particulate matter when phytoplankton biomass, indicated from the chlorophyll-a concentration in a particle, was higher. In the low algal season, when [chlorophyll-a] −1 , the bacterial number, instead of chlorophyll-a concentration in particle, showed a positive correlation with the particle–water partition coefficient of Hg. Overall, microbial abundance seems to play a critical role in particle scavenging of Hg in coastal water. Taking this result in light of Hg in pristine coastal zones, we predict that increases in algal biomass amplify the potential for algae to transfer Hg to marine food chains. - Highlights: • Abundance of phytoplankton and bacteria influenced particle–water partitioning of Hg. • More Hg partitioned toward particles when microorganism biomass in particle is large. • Increases of algal biomass may enhance Hg bioaccumulation in coastal ecosystem

Influence of microorganism content in suspended particles on the particle–water partitioning of mercury in semi-enclosed coastal waters

Energy Technology Data Exchange (ETDEWEB)

Jang, Jiyi [School of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712 (Korea, Republic of); Global Bioresources Research Center, Korea Institute of Ocean Science and Technology (KIOST), Ansan 426-744 (Korea, Republic of); Kim, Hyunji [School of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712 (Korea, Republic of); Han, Seunghee, E-mail: shan@gist.ac.kr [School of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 500-712 (Korea, Republic of)

2014-02-01

It is known that particle scavenging of mercury (Hg) can be affected by the abundance of particulate organic matter in coastal waters. However, the role of living organic particles in Hg scavenging is not yet completely understood. In this study, we hypothesized that an abundance of living organic particles (i.e., phytoplankton and bacteria) would influence the particle–water partitioning of Hg in coastal waters. Surface seawater samples were collected from eight stations in Gwangyang Bay, Korea, in three seasons (November 2009, April 2010, and October 2010) for the determination of concentrations of suspended particulate matter (including chlorophyll-a and bacteria), and Hg in unfiltered and filtered waters. We found that more Hg partitioned toward particulate matter when phytoplankton biomass, indicated from the chlorophyll-a concentration in a particle, was higher. In the low algal season, when [chlorophyll-a] < 0.6 μg L{sup −1}, the bacterial number, instead of chlorophyll-a concentration in particle, showed a positive correlation with the particle–water partition coefficient of Hg. Overall, microbial abundance seems to play a critical role in particle scavenging of Hg in coastal water. Taking this result in light of Hg in pristine coastal zones, we predict that increases in algal biomass amplify the potential for algae to transfer Hg to marine food chains. - Highlights: • Abundance of phytoplankton and bacteria influenced particle–water partitioning of Hg. • More Hg partitioned toward particles when microorganism biomass in particle is large. • Increases of algal biomass may enhance Hg bioaccumulation in coastal ecosystem.

Soil organic matter regulates molybdenum storage and mobility in forests

Science.gov (United States)

Marks, Jade A; Perakis, Steven; King, Elizabeth K.; Pett-Ridge, Julie

2015-01-01

The trace element molybdenum (Mo) is essential to a suite of nitrogen (N) cycling processes in ecosystems, but there is limited information on its distribution within soils and relationship to plant and bedrock pools. We examined soil, bedrock, and plant Mo variation across 24 forests spanning wide soil pH gradients on both basaltic and sedimentary lithologies in the Oregon Coast Range. We found that the oxidizable organic fraction of surface mineral soil accounted for an average of 33 %of bulk soil Mo across all sites, followed by 1.4 % associated with reducible Fe, Al, and Mn-oxides, and 1.4 % in exchangeable ion form. Exchangeable Mo was greatest at low pH, and its positive correlation with soil carbon (C) suggests organic matter as the source of readily exchangeable Mo. Molybdenum accumulation integrated over soil profiles to 1 m depth (τMoNb) increased with soil C, indicating that soil organic matter regulates long-term Mo retention and loss from soil. Foliar Mo concentrations displayed no relationship with bulk soil Mo, and were not correlated with organic horizon Mo or soil extractable Mo, suggesting active plant regulation of Mo uptake and/or poor fidelity of extractable pools to bioavailability. We estimate from precipitation sampling that atmospheric deposition supplies, on average, over 10 times more Mo annually than does litterfall to soil. In contrast, bedrock lithology had negligible effects on foliar and soil Mo concentrations and on Mo distribution among soil fractions. We conclude that atmospheric inputs may be a significant source of Mo to forest ecosystems, and that strong Mo retention by soil organic matter limits ecosystem Mo loss via dissolution and leaching pathways.

Roles of epi-anecic taxa of earthworms in the organic matter recycling

Science.gov (United States)

Hoeffner, Kevin; Monard, Cécile; Santonja, Mathieu; Pérès, Guénola; Cluzeau, Daniel

2017-04-01

Given their impact on soil functioning and their interactions with soil organisms, earthworms contribute to the recycling of organic matter and participate significantly in the numerous ecosystem services provided by soils. Most studies on the role of earthworms in organic matter recycling were conducted at the level of the four functional groups (epigeic, epi-anecic, anecic strict and endogeic), but their effects at taxa level remain largely unknown. Still, within a functional group, anatomic and physiologic earthworm taxa traits are different, which should impact organic matter recycling. This study aims at determining, under controlled conditions, epi-anecic taxa differences in (i) leaf litter mass loss, (ii) assimilation and (iii) impact on microorganisms communities implied in organic matter degradation. In seperate microcosms, we chose 4 epi anecic taxa (Lumbricus rubellus, Lumbricus festivus, Lumbricus centralis and Lumbricus terrestris). Each taxon was exposed separately to leaves of three different plants (Holcus lanatus, Lolium perenne and Corylus avellana). In the same microcosm, leaves of each plant was both placed on the surface and buried 10cm deep. The experiment lasted 10 days for half of the samples and 20 days for the second half. Microorganisms communities were analysed using TRFLP in each earthworm taxon burrow walls at 20 days. We observed differences between epi-anecic taxa depending on species of plant and the duration of the experiment. Results are discussed taking into account physical and chemical properties of these 3 trophic resources (e.g. C/N ratio, phenolic compounds, percentage of lignin and cellulose...).

Contribution of suspended particulate matter and zooplankton to MeHg contamination of the food chain in mid-northern Quebec (Canada) reservoirs

International Nuclear Information System (INIS)

Plourde, Y.; Lucotte, M.; Pichet, P.

1997-01-01

The high increase in mercury (Hg) concentrations in fish following the creation of hydroelectric reservoirs was discussed. Flooded forest soils are a major source of mercury contamination of fish after impoundment. Flooding stimulates bacterial activity in the humic horizon of soils and results in the transformation of inorganic mercury into methyl mercury (MeHg), the most toxic form of mercury. The reservoirs of the La Grande hydroelectric complex at James Bay in northern Quebec were sampled and compared to neighbouring natural lakes. Sampling was carried out in 1992 during June, August and September. Results of the analysis revealed an increase in the MeHg concentrations in zooplankton and suspended particulate matter (SPM); mean concentrations were about 5 times higher in the reservoirs than in neighbouring lakes. Although the process is not well understood, it is believed that the MeHg is transferred up the food chain which accounts, in part, for MeHg contamination of fishes. 45 refs., 9 figs

Soil Organic Matter Accumulation and Carbon Fractions along a Moisture Gradient of Forest Soils

Directory of Open Access Journals (Sweden)

Ewa Błońska

2017-11-01

Full Text Available The aim of the study was to present effects of soil properties, especially moisture, on the quantity and quality of soil organic matter. The investigation was performed in the Czarna Rózga Reserve in Central Poland. Forty circular test areas were located in a regular grid of points (100 × 300 m. Each plot was represented by one soil profile located at the plot’s center. Sample plots were located in the area with Gleysols, Cambisols and Podzols with the water table from 0 to 100 cm. In each soil sample, particle size, total carbon and nitrogen content, acidity, base cations content and fractions of soil organic matter were determined. The organic carbon stock (SOCs was calculated based on its total content at particular genetic soil horizons. A Carbon Distribution Index (CDI was calculated from the ratio of the carbon accumulation in organic horizons and the amount of organic carbon accumulation in the mineral horizons, up to 60 cm. In the soils under study, in the temperate zone, moisture is an important factor in the accumulation of organic carbon in the soil. The highest accumulation of carbon was observed in soils of swampy variant, while the lowest was in the soils of moist variant. Large accumulation of C in the soils with water table 80–100 cm results from the thick organic horizons that are characterized by lower organic matter decomposition and higher acidity. The proportion of carbon accumulation in the organic horizons to the total accumulation in the mineral horizons expresses the distribution of carbon accumulated in the soil profile, and is a measure of quality of the organic matter accumulated. Studies have confirmed the importance of moisture content in the formation of the fractional organic matter. With greater soil moisture, the ratio of humic to fulvic acids (HA/FA decreases, which may suggest an increase in carbon mobility in soils.

Particulate organic matter predicts bacterial productivity in a river dominated estuary

Science.gov (United States)

Crump, B. C.

2015-12-01

Estuaries act as coastal filters for organic and inorganic fluvial materials in which microbial, biogeochemical, and ecological processes combine to transform organic matter and nutrients prior to export to the coastal ocean. The function of this estuarine 'bioreactor' is linked to the residence times of those materials and to rates of microbial heterotrophic activity. Our ability to forecast the impact of global change on estuarine bioreactor function requires an understanding of the basic controls on microbial community activity and diversity. In the Columbia River estuary, the microbial community undergoes a dramatic seasonal shift in species composition during which a spring bacterioplankton community, dominated by Flavobacteriaceae and Oceanospirillales, is replaced by a summer community, dominated by Rhodobacteraceae and several common marine taxa. This annual shift occurs in July, following the spring freshet, when river flow and river chlorophyll concentration decrease and when estuarine water residence time increases. Analysis of a large dataset from 17 research cruises (1990-2014) showed that the composition of particulate organic matter in the estuary changes after the freshet with decreasing organic carbon and nitrogen content, and increasing contribution of marine and autochthonous estuarine organic matter (based on PO13C and pigment ratios). Bacterial production rates (measured as leucine or thymidine incorporation rates) in the estuary respond to this change, and correlate strongly with labile particulate nitrogen concentration and temperature during individual sampling campaigns, and with the concentration of chlorophyll in the Columbia River across all seasons. Regression models suggest that the concentration of labile particulate nitrogen and the rate of bacterial production can be predicted from sensor measurements of turbidity, salinity, and temperature in the estuary and chlorophyll in the river. These results suggest that the quality of