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1.
Till Francke Sandra Werb Erik Sommerer José Andrés López-Tarazón 《Journal of Soils and Sediments》2014,14(12):1909-1920
Purpose
The Isábena catchment (445 km2), Spain, features highly diverse spatial heterogeneity in land use, lithology and rainfall. Consequently, the relative contribution in terms of water and sediment yield varies immensely between its subcatchments, and also temporally. This study presents the synthesis of ~2.5 years of monitoring rainfall, discharge and suspended sediment concentration (SSC) in the five main subcatchments of the Isábena and its outlet.Materials and methods
Continuous discharge at the subcatchment outlets, nine tipping bucket rainfall and automatic SSC samplers (complemented by manual samples), were collected from June 2011 until November 2013. The water stage records were converted to discharge using a rating curve derived with Bayesian regression. For reconstructing sediment yields, the data from the intermittent SSC sampling needed to be interpolated. We employed non-parametric multivariate regression (Quantile Regression Forests, QRF) using the discharge and rainfall data plus different aggregation levels of these as ancillary predictors. The subsequent Monte Carlo simulations allowed the determination of monthly sediment yields and their uncertainty.Results and discussion
The stage–discharge rating curves showed wide credibility intervals for the higher stages, with great uncertainties associated with the discharge rates, especially during floods. The water yield of the subcatchments differed considerably. The entire catchment’s output was dominated by the northernmost subcatchment (~360 mm year?1). The smaller, southern subcatchments featured much higher variability and lower runoff rates (55–250 mm year?1). The SSCs exhibited a wide range and can exceed 100 g l?1 for the central subcatchments, where most of the badlands are located. For the reconstruction of the sedigraphs, the QRF method proved suitable with Nash–Sutcliffe indices of 0.50 to 0.84. The specific sediment yield ranges from relatively low (32 t km?2 year?1) in the highly vegetated north to high values (3,651 t km?2 year?1) in areas with many badland formations.Conclusions
The Isábena catchment shows high erosion dynamics with great variability in space and time, with stark contrasts even between adjacent subcatchments. The natural conditions make water and sediment monitoring and instrumentation very challenging; the measurement of discharge is particularly prone to considerable uncertainties. The QRF method employed for reconstructing sedigraphs and monthly yields proved well suited for the task. 相似文献2.
The antifoulant agents, bis-(tributyltin) oxide (TBTO), tributyltin acetate (TBTOAc) and tributyltin chloride (TBTCI) were mixed with various media. These media included distilled water, seawater, aerobic and anaerobic sediments. The Mossbauer spectra of the chloroform extracts of the distilled water and seawater mixed with these compounds were examined. The componds were mixed with aerobic and anaerobic sediments, and the Mossbauer spectra of the sediments were also examined. TBTO was converted to the hydroxide compound in all media except in anaerobic sediment where it was converted to an unidentified compound. TBTOAc and TBTCI were not changed by mixing with distilled water and aerobic sediment but were converted to the hydroxide compound in seawater and in anaerobic sediment. 相似文献
3.
Sediments in urban river basins: a review of sediment–contaminant dynamics in an environmental system conditioned by human activities 总被引：1，自引：1，他引：0
Background, aim and scope Over 50% of the global population live in urban centres and, therefore, an understanding of the processes acting upon urban
systems is a global issue. The nature of human-made, often impervious, land surfaces and heavily engineered waterways results
in hydrological and sedimentological systems in urbanised basins which contrast significantly to those within more natural
(i.e. pristine, forested, agricultural) aquatic systems. In addition, the abundance of contamination sources in urban systems
results in chemical pressures often manifested as high pollution concentrations or loadings, which in turn have detrimental
impacts on human and ecosystem health. These lead to management and sustainability issues not generally encountered in more
natural environments. The purpose of this review is to provide a state-of-the-art assessment of sediment sources, pathways
and storage within urban river systems, to consider sediment management within urban systems and river basins, and examine
the role of local and global environmental changes on sediment processes and management. Inevitably, much of the sediment
that is transported within urbanised basins is contaminated, so this review also considers sediment–contaminant sources and
interactions.
Conclusions and recommendations We reach a number of conclusions and recommendations for future research. There is a need for better sampling and monitoring
of sediment and sediment-associated contaminant fluxes and cycling in urban river channels and basins. This should include
better techniques and studies to identify sources and transfers of road-deposited sediment (RDS), airborne particulate matter
and sediments in the river system. Greater interdisciplinary research, combining sedimentologists, hydrologists, urban planners,
urban archaeologists, chemists and biologists, is needed. More attention needs to focus on upscaling and connecting urban
areas to the rest of the river basin, both upstream and downstream. Finally, there is a need to balance multiple needs (urban
population, water resources) with likely trends in both urban development and global environmental change. 相似文献
4.
Eirin Sva Stomperudhaugen Katherine Langford Morten Schaanning Ketil Hylland 《Journal of Soils and Sediments》2014,14(8):1469-1478
Purpose
The aim of this study was to quantify the release of the hydrophobic contaminant emamectin (EMA) from marine sediments in response to inputs of organic material (OM) and/or oil, in the presence or absence of two different bioturbating species. Specifically, it was designed to test whether oil would decrease the release of EMA and whether OM and/or the presence of bioturbating macrofauna would increase the release of EMA from sediment.Materials and methods
Experimental sediments were spiked with EMA (5 μg kg?1 wet sediment). The different treatments were prepared by the addition of OM (310 g algae m?2) and/or an aliphatic oil (29.6 g oil m?2). In addition, two bioturbating species, Brissopsis lyrifera or Ennucula tenuis, were added in some aquaria, resulting in a total of 12 treatments with four replicates each. Water samples for analyses of silicate and EMA and sediment samples for analyses of total organic carbon (TOC) were taken at the start and end of the experimental exposure. In addition, oxygen was measured during the experimental period of 8 days. Fluxes were calculated and compared between treatments using generalised linear models (GLMs).Results and discussion
The EMA release flux was significantly increased in treatments with added OM, possibly reflecting the presence of soluble complexes formed between EMA and dissolved OM. The presence of B. lyrifera caused a small, but statistically significant, increase in EMA release from sediment. This species would be expected to have a stronger effect on bioirrigation and particle mixing than E. tenuis, particularly when the population density of the latter species is low (as in the present experiment). There were no consistent effects of oil in this experiment, but the presence of oil decreased the EMA release flux when co-occurring with added OM and/or B. lyrifera. Increased retention of hydrophobic contaminants in the presence of oil is consistent with the existing literature on contaminant fate.Conclusions
The results from this study highlight the need to consider both the infauna present in polluted areas and the level of organic enrichment of the sediment when modelling the environmental fate of hydrophobic contaminants. It also highlights that labile OM and refractory oil appear to differ in their effects on the remobilisation of hydrophobic organic contaminants, by reducing and increasing release, respectively. 相似文献5.
Mahoney David Tyler Al Aamery Nabil Fox James Forrest Riddle Brenden Ford William Wang Y. T. 《Journal of Soils and Sediments》2019,19(9):3332-3356
Journal of Soils and Sediments - The equilibrium sediment exchange process is defined as instantaneous deposition of suspended sediment to the streambed countered by equal erosion of sediment from... 相似文献
6.
Glaucia Pantano Vitor C. Ferrizzi Márcia C. Bisinoti Altair B. Moreira 《Journal of Soils and Sediments》2016,16(5):1599-1611
Purpose
Polycyclic aromatic hydrocarbons (PAHs) are unintentional products that are classified as persistent toxic substances. The goal of the present study was to generate data on the presence of 15 priority PAHs that are found in surface sediment and core sediment in the region of the Turvo/Grande watershed, São Paulo State, Brazil, which is an area of expanding sugarcane cultivation, and to correlate these data with the sources of these PAHs and the guiding values for sediment quality analysis.Materials and methods
Surface sediments and sediment cores were sampled during the rainy and dry seasons in February and July 2010. The extraction of PAHs from sediments was performed using a Soxhlet extractor, and then the extract was cleaned according to the methods of the US EPA 3630C (US EPA 1996) using a silica gel column. Quantification was performed using high performance liquid chromatography with fluorescence detection.Results and discussion
The concentrations of all 15 PAHs decreased as the depth of the sediment core increased. Overall, the concentrations decreased along the sediment core; however, the RTURARG (region predominantly used for planting sugarcane and livestock) during the rainy season and the CAPRP sampling site (located at part of the Preto River dam) during the dry season showed increased concentrations in the first few sediment fractions, and then the concentrations decreased. Higher concentrations were observed in urban locations, and the concentration of naphthalene was higher than the probable effect level (PEL) determined by the Canadian environmental agency. The obtained diagnostic ratios indicate that the sediment from areas with an abundance of sugarcane was a pyrolytic source of PAHs, which indicates a contribution from burning straw to the PAH concentrations in those areas.Conclusions
For all sampling sites and all PAHs, we found a decreasing trend in PAH concentrations with increasing sediment core depth, and the locations, such as CAPRP, that experienced a higher level of human activity had the highest total concentrations of PAHs. These locations were the only areas in which the PAH naphthalene was found in higher concentrations than the PEL. The diagnostic ratios reveal that regions with sugarcane plantations had predominantly pyrolytic sources of PAHs, indicating the contribution of PAHs from sugarcane straw burning.7.
Leticia M. Mesa Cecilia Maldini Gisela Mayora Miguel Saigo Mercedes Marchese Federico Giri 《Journal of Soils and Sediments》2016,16(9):2316-2325
Purpose
The study was carried out in a wetland of the Middle Paraná River system, Argentina, in order to evaluate the processes associated with the decomposition of manure, which includes changes in chemical composition, nutrient release of manure, and colonization of invertebrates. We also compared the invertebrate assemblage that colonized manure with that present in the benthos of the wetland.Materials and methods
Nylon bags were filled with fresh cattle manure and anchored to the littoral zone of the wetland. Six bags were collected after 1, 2, 6, 14, 21, 28, 33, 55, and 79 days: three for invertebrate determination and the other three bags for determination of dry mass and chemical analyses. The nutrient content, cellulose, lignin, and total phenolic compounds of manure were determined. In addition, the leachate of manure was collected for nutrient analyses. Samples of the wetland benthic sediment were collected for benthic invertebrate determination and particle size analyses. Spearman rank correlation was used to evaluate the relationship between chemical compounds of manure and breakdown rate. Principal component analysis was used to explore invertebrate assemblage composition of manure and sediment during the experiment.Results and discussion
Limnodrilus, Dero, and Chironomus were dominant in the manure. Gatherer-collector was the dominant group in the manure, comprising almost 95 % of the total density of invertebrates. Breakdown rate was significantly related with nutrients, cellulose and total phenolics of manure. An ordination plot showed changes in invertebrate assemblages of manure and sediment samples over time.Conclusions
This study provides new insight on the importance of manure as a substrate for macroinvertebrate colonization. Cattle manure needs to be considered as a potential source of nutrients for aquatic systems and a substrate for invertebrate assemblages.8.
Hazard identification of contaminated sites—ranking potential toxicity of organic sediment extracts in crustacean and fish 总被引：1，自引：0，他引：1
Jenny Karlsson Henrik Sundberg Gun Åkerman Kerstin Grunder Britta Eklund Magnus Breitholtz 《Journal of Soils and Sediments》2008,8(4):263-274
Background, aim, and scope It is well known that contaminated sediments represent a potential long-term source of pollutants to the aquatic environment.
To protect human and ecosystem health, it is becoming common to remediate contaminated sites. However, the great cost associated
with, e.g., dredging in combination with the large numbers of contaminated sites makes it crucial to pinpoint those sites
that are in greatest need of remediation. In most European countries, this prioritization process has almost exclusively been
based on chemical analyses of known substances; only seldom toxicity data has been considered. The main objective of the current
study was therefore to develop a tool for hazard identification of sediment by ranking potential toxicity of organic sediment
extracts in a crustacean and a fish. A secondary objective was to investigate the difference in potential toxicity between
compounds with different polarities.
Materials and methods Early life stages of the crustacean Nitocra spinipes and the fish Oncorhynchus mykiss, which represent organisms from different trophic levels (primary and secondary consumer) and with different routes of exposure
(i.e., ingestion through food, diffusive uptake, and maternal transfer), were exposed to hexane and acetone fractions (semi-polar
compounds) of sediment from five locations, ranging from heavily to low contaminated. Preliminary tests showed that the extracts
were non-bioavailable to the crustacean when exposed via water, and the extracts were therefore loaded on silica gel. Rainbow
trout embryos were exposed using nano-injection technique.
Results and discussion Clear concentration–response relationships of both mortality and larval development were observed in all tests with N. spinipes. Also for rainbow trout, the observed effects (e.g., abnormality, hemorrhage, asymmetric yolk sac) followed a dose-related
pattern. Interestingly, our results indicate that some of the locations contained toxic semi-polar compounds, which are normally
not considered in risk assessment of sediment since they are focused on compounds isolated in the hexane fraction.
Conclusions The ranking of the five sediments followed the expected pattern of potential toxicity in both organisms, i.e., sediments with
known pollution history caused major effects while reference sediments caused minor effects in the two test systems. Silica
gel turned out to be an excellent carrier for exposure of N. spinipes to very hydrophobic and otherwise non-bioavailable sediment extracts.
Recommendations and perspectives Since both test systems demonstrated that a substantial part of the potential toxicity was caused by semi-polar compounds
in the acetone fractions, this study enlightens our poor understanding of which compounds are causing adverse effects in environmental
samples. Therefore, by investigating potential toxicity (i.e., hazard identification) as a first screening step in prioritizing
processes, these implications could be avoided. For proper sediment risk assessment, we however recommend whole sediment toxicity
tests to be used for selected sites at following tiers. 相似文献
9.
Background, aim, and scope
The cause for this position paper is the impression that risk assessors consider primarily the concentration of free metal ions dissolved in solution controlling metal bioavailability in aquatic systems. Aiming at a more realistic risk assessment of metals, bioavailability has to be discussed under the scope of main uptake routes of metals to organisms. 相似文献10.
Oldrich Navratil Olivier Evrard Michel Esteves Sophie Ayrault Irène Lefèvre Cédric Legout Jean-Louis Reyss Nicolas Gratiot Julien Nemery Nicolle Mathys Alain Poirel Philippe Bonté 《Journal of Soils and Sediments》2012,12(9):1463-1478
Purpose
Quantifying suspended sediment fluxes and dynamics across mountains, and identifying the origin of sediment in severely eroded areas, are of primary importance for the management of water resources. This contribution aims to generalise previous results from suspended sediment fingerprinting obtained during 2007?C2009 in a mesoscale Alpine catchment (the Bléone River; 905?km2) in France, and to assess variability in sediment sources throughout the second half of the twentieth century.Materials and methods
Sediment fingerprinting, based on elemental geochemistry and radionuclide measurements, was conducted on a sediment core collected in an alluvial floodplain at the basin outlet. This technique was combined with hydro-sedimentary time-series to reconstruct the origin of suspended sediment deposited at this location over the last 50?years.Results and discussion
Interpretation of sedimentation based on historical hydrological databases corroborates core dating obtained with 137Cs and 210Pbxs activity measurements. Black marls and (marly) limestone sources provided the main fraction of sediment throughout the sequence (40 and 22?%, respectively). However, we also found evidence for the occurrence of major floods carrying large quantities of sediment originating from Quaternary deposits and conglomerates (25 and 16?%, respectively). The variability of sediment sources throughout the sequence may reflect the spatial variability of rainfall within the catchment, which in turn reflects its origin. However, the relatively homogeneous sediment composition throughout the sequence confirms that core-derived information is representative of widespread flood events.Conclusions
These results are consistent with those obtained in previous studies. They also outline the need to take into account the entire grain size range of fine sediment in order to provide an overall picture of sediment sources and transfers within highly erosive catchments. This study also emphasizes the importance of using archival data to validate the results of sediment fingerprinting studies conducted during short contemporary monitoring programmes, and to extend fingerprinting of sediment sources over longer time-scales which include large and widespread floods. 相似文献11.
12.
Arnold V. Hallare Thomas-Benjamin Seiler Henner Hollert 《Journal of Soils and Sediments》2011,11(1):141-173
Purpose
Sediments serve as integral and dynamic parts of our aquatic systems. Within the last 15 to 20 years, however, the scientific community has begun noticing deterioration of sediment quality at an alarming rate worldwide. Sediments are now harboring hazardous pollutants that can directly influence water quality, thereby creating very stressful conditions for aquatic life. As a consequence, global efforts were initiated in the early 1970s, to find ways to assess sediment quality. Because of their obvious ecological and economic significance, fish have remained a major taxonomic group for appraising the general quality of aquatic systems. However, for sediment risk assessment, fish have lagged behind invertebrates due to their mobility and generally, pelagic lifestyle. To our knowledge, this is the first paper that comprehensively presents and reviews the versatile role of fish in assessing the state of health of aquatic sediments. 相似文献13.
14.
《CATENA》1999,35(1):41-63
Within a few decades of European settlement, channel incision transformed discontinuous river courses throughout Wolumla catchment, on the south coast of New South Wales, Australia. The development of continuous channels greatly increased sediment delivery from the catchment. This paper documents the character, timing and proportion of sediment sourced from upland valley fills, channel expansion sites, and gully networks. Volumes of material transferred from these sources are compared with estimates of sediment eroded from hillslopes, and the movement of sediment off the slopes to the valley floor is assessed. Although disturbance of slopes resulted in significant movement of materials, most of this material has been stored on-slope, in trapped tributary fills and along lower order drainage lines. The slopes are effectively decoupled from the channel. Sediment accumulation in farm dams over the past few decades has been negligible. Around 75% of the total volume of material released from creeks in Wolumla catchment since 1865, i.e., 5500×103 m3, has been derived from channel incision into valley fills at the base of the escarpment. Sediment flushing occurred within a few decades of catchment disturbance. Bedrock confinement in the middle and lower catchment resulted in very efficient downstream transfer of materials. Although gully networks and channel expansion sites have released a relatively small volume of material, these sources are the greatest contemporary source of sediment in Wolumla catchment. 相似文献
15.
Granado-Lorencio F Donoso-Navarro E Sánchez-Siles LM Blanco-Navarro I Pérez-Sacristán B 《Journal of agricultural and food chemistry》2011,59(21):11819-11824
Bioactive compounds are used in the design and development of new food products with potential health benefits, although little is known regarding their bioavailability and interactions. This study assessed the stability, in vitro bioaccessibility, and human bioavailability of β-cryptoxanthin from β-cryptoxanthin-rich drinks with and without added phytosterols developed for this purpose. The developed drinks showed no difference in the content of β-cryptoxanthin, and they were stable over 6 months. In vitro, hydrolysis of β-cryptoxanthin esters and the amount of free β-cryptoxanthin at duodenal and micellar phases were similar regardless of the presence of phytosterols. In the human study, the daily intake provoked significant increments of β-cryptoxanthin in serum regardless of the type of the drink. In conclusion, in vitro and in vivo human studies have shown that the bioavailability of β-cryptoxanthin is not significantly affected by the presence of phytosterols when they are simultaneously supplied in a drink. 相似文献
16.
Zhou Yanwen Wang Haixiang Zhang Yinlong Cai Yiwei Yin Hongbin Yang Zhen Li Qiang Yuan Hezhong 《Journal of Soils and Sediments》2021,21(10):3274-3288
Journal of Soils and Sediments - Desorption of phosphorus (P) bound to iron-containing minerals (Fe-P) is a crucial component of the eutrophication process in lakes. However, the main process and... 相似文献
17.
Hu Beibei Wang Dongqi Meng Weiqing Zhou Jun Sun Zongbin Liu Xiaolong 《Journal of Soils and Sediments》2020,20(8):3243-3253
Purpose
The purposes of this study were to analyse the spatiotemporal variations in greenhouse gas diffusive fluxes at the sediment–water interface of sewage-draining rivers and natural rivers, and investigate the factors responsible for the changes in greenhouse gas diffusive fluxes.
Materials and methodsGreenhouse gas diffusive fluxes at the sediment–water interface of rivers in Tianjin city (Haihe watershed) were investigated during July and October 2014, and January and April 2015 by laboratory incubation experiments. The influence of environmental variables on greenhouse gas diffusive fluxes was evaluated by Spearman’s correlation analysis and a multiple stepwise regression analysis.
Results and discussionSewage-draining rivers were more seriously polluted by human sewage discharge than natural rivers. The greenhouse gas diffusive fluxes at the sediment–water interface exhibited obvious spatiotemporal variations. The mean absolute value of the CO2 diffusive fluxes was seasonally variable with spring>winter>fall>summer, while the mean absolute values of the CH4 and N2O diffusive fluxes were both higher in summer and winter, and lower in fall and spring. The annual mean values of the CO2, CH4 and N2O diffusive fluxes at the sewage-draining river sediment–water interface were ??123.26?±?233.78 μmol m?2 h?1, 1.88?±?6.89 μmol m?2 h?1 and 1505.03?±?2388.46 nmol m?2 h?1, respectively, which were 1.22, 4.37 and 134.50 times those at the natural river sediment–water interface, respectively. The spatial variation of the N2O diffusive fluxes in the sewage-draining rivers and the natural rivers was the most significant. As a general rule, the more serious the river pollution was, the greater the diffusive fluxes of the greenhouse gases were. On average for the whole year, the river sediment was the sink of CO2 and the source of CH4 and N2O. There were positive correlations among the CO2, CH4 and N2O diffusive fluxes. The main influencing factor for CO2 and N2O diffusive fluxes was the water temperature of the overlying water; however, the key factors for CH4 diffusive fluxes were the Eh of the sediment and the NH4+-N of the overlying water.
ConclusionsRiver sediment can be either a sink or a source of greenhouse gases, which varies in different levels of pollution and different seasons. Human sewage discharge has greatly affected the carbon and nitrogen cycling of urban rivers.
相似文献18.
Gemma Piqué José A. López-Tarazón Ramon J. Batalla 《Journal of Soils and Sediments》2014,14(12):2031-2044
Purpose
In-channel sediment storage is a fundamental component of a river basin’s sediment budget. Sediment remains stored until a competent flow re-suspends and transfers it downstream. The objectives of this paper are: (1) to quantify in-channel sediment storage and its spatial and temporal dynamics in the River Isábena, a mesoscale mountainous catchment draining highly erodible areas (badlands) in the south central Pyrenees (Ebro basin) and (2) to analyse changes in storage in the mainstem channel in relation to sediment yield from the main tributaries.Materials and methods
In-channel sediment storage was measured seasonally (from winter 2011 to winter 2012) at 14 mainstem cross-sections using a re-suspension cylinder. A minimum of three locations were sampled at each section, and two levels of agitation were applied. Samples allowed determination of the amount of sediment accumulated per unit surface area at a given point in the river; estimates of the total storage in the bed of the mainstem Isábena were derived from these data. In addition, main five tributaries were monitored for discharge and suspended sediment transport.Results and discussion
Results show an annual sedimentary cycle, with the sediment being produced in badlands during winter, transferred to the main channel during spring, stored in the river during summer and, finally, exported out of the basin by the autumn floods. Marked spatial variability was observed; sections located immediately downstream from the main tributaries (i.e. mainly Villacarli) generally held larger amounts of sediment in the bed. Runoff and sediment inputs from the tributaries were the most important factors determining sediment storage and its spatial and temporal dynamics. The overall sediment yield of the Isábena was much higher than the in-channel sediment storage, despite the large amounts stored in the channel.Conclusions
This finding corroborates a previous published hypothesis that fine sediment in the drainage network has a mean residence time of the order of 1 year and that the basin’s delivery ratio exceeds 90 %; both of these characteristics can be related to the high connectivity between production areas (badlands) and the river network, and to the role of baseflows allowing continuous export of sediment from the catchment. 相似文献19.
《CATENA》1998,32(1):1-14
Some earlier studies of erosion of the schist-dominated waste rock dump of Ranger Uranium Mine, Northern Territory, Australia, used turbidity as a surrogate for sediment concentration. Subsequent detailed studies of the turbidity–sediment concentration relation for a number of sites on the waste rock dump, reported in this paper, demonstrate that turbidity cannot be used to accurately predict sediment concentration. The results of this experiment suggest that environmental monitoring of erosion at mines in the Kakadu region of Northern Australia should use direct methods of measurement of the sediment concentration in runoff, and that turbidity measurements will not provide sufficient accuracy to satisfy audits of environmental compliance to regulatory guidelines. 相似文献
20.