Scanner derived colour parameters to determine suspended sediment sources in burned catchments

2020 ◽  
Author(s):  
Julián García-Comendador ◽  
Núria Martínez-Carreras ◽  
Josep Fortesa ◽  
Antoni Borràs ◽  
Aleix Calsamiglia ◽  
...  
Keyword(s):  
Suspended Sediment ◽  
Fire Management ◽  
Overland Flow ◽  
Management Strategies ◽  
Economic Cost ◽  
Suspended Sediments ◽  
Sediment Source ◽  
Sediment Sources ◽  
Geochemical Properties ◽  
Colour Parameters

<p>After a wildfire, total or partial removal of vegetal biomass and changes in physicochemical soil properties can lead to an increase in overland flow and sediment yield. Eventual damage must be counteracted urgently identifying erosion hotspots, implementing post-fire management programmes and sampling campaigns to check its effectiveness. Under this context, the sediment source fingerprinting technique is widely used for determining the origin of suspended sediments in catchments and can be useful to evaluate the effectiveness of sediment management programmes. It traditionally relies on the use of physical, biochemical and geochemical properties as tracers. However, measuring these tracers in the laboratory often entails a high economic cost and time consuming. Colour tracers were proven to greatly reduce this cost and measuring time, especially if measurements are done using a common office scanner. Here we propose that colour parameters can be used to investigate SS origin in burned catchments. To this end, we created artificial mixtures of sediment and ash to verify the colour linear additivity and the ash influence on colour parameters. We then used colour parameters for source-ascription of SS samples (n=9) collected during two years after a fire in small Mediterranean catchment (4.8 km<sup>2</sup>; Mallorca, Spain). Furthermore, reflectance-derived colour parameters were compared with those obtained using a current office scanner. The high correlation between most chromatic indexes (obtained using both methods; p < 0.01) suggested that scanning is a good alternative for measuring soil and sediment colour. A Bayesian tracer mixing model (MixSIAR) was applied to determine the relative contribution of each source. The type of mixing models allowed to appropriately represent natural and sampling uncertainty in tracer data. During the first events, suspended sediment was mainly originated in burned surfaces, whereas its contribution decreased throughout the study period. Tracing results obtained using colour parameters were compared with estimations using <sup>137</sup>Cs and <sup>210</sup>Pb<sub>ex</sub>, as recognized tracers to discriminate between surface and subsurface sediment sources after wildfires. Estimated source ascriptions with both methods (i.e. reflectance-derived colour parameters and radionuclides) matched in 88% of the samples measured. Colour tracers have been proved to be useful to discriminate between burned and unburned sources, making them suitable for suspended sediment source ascription and monitoring as part of post-fire management strategies.</p><p><em>This work was supported by the research project CGL2017-88200-R “Functional hydrological and sediment connectivity at Mediterranean catchments: global change scenarios –MEDhyCON2” funded by the Spanish Ministry of Science, Innovation and Universities, the Spanish Agency of Research (AEI) and the European Regional Development Funds (ERDF)</em></p>

Analysis of post-fire suspended sediment sources by using colour parameters

Geoderma ◽  
2020 ◽  
Vol 379 ◽  
pp. 114638 ◽  
Author(s):  
Julián García-Comendador ◽  
Núria Martínez-Carreras ◽  
Josep Fortesa ◽  
Antoni Borràs ◽  
Aleix Calsamiglia ◽  
...  
Keyword(s):  
Suspended Sediment ◽  
Sediment Sources ◽  
Colour Parameters

Improving spatial representation of erosion sources using Sediment Fingerprinting with terrain data and sediment budget modelling

2020 ◽  
Author(s):  
Simon Vale ◽  
Hugh Smith
Keyword(s):  
Suspended Sediment ◽  
Source Apportionment ◽  
End Users ◽  
Sediment Budget ◽  
Storm Event ◽  
Sediment Source ◽  
Sediment Fingerprinting ◽  
Sediment Sources ◽  
Geochemical Tracers ◽  
Source Contributions

<p>Sediment fingerprinting quantifies proportional contributions of catchment sediment sources to downstream sediment mixtures and deposits. While the sediment fingerprinting technique is well established it is still challenged by the coarse spatial resolution of sediment source discrimination which hinders understanding of catchment sediment dynamics and limits its usefulness for land management where finer resolution spatial information is required.</p><p>Here, two conventional sediment fingerprinting datasets from New Zealand are used to show how spatial modelling of source loads can improve 1) the usefulness of sediment fingerprinting approaches and 2) visualization of results for end-users by combining source apportionment with terrain information and sediment budget modelling. The two case studies involve unmixing sediment source contributions to 1) overbank deposits within the Oroua River catchment, where six sediment sources (Mountain Range, Mudstone, Hill Subsurface, Hill Surface, Unconsolidated Sandstone, and Channel Bank) across two size fractions (<63 µm and 125–300 µm) were characterized using bulk geochemical and radionuclide tracers and 2) suspended sediment in the Manawatu catchment, where a similar six sources were characterized using bulk geochemical tracers to determine changes in source contributions to hourly suspended sediment samples during a 53hr storm event.</p><p>The proportional source contributions for each case study are applied to modelled sediment loads and spatially distributed using terrain information for rock type, slope and channel network extent to produce specific sediment yield maps for both catchments and spatial visualization of sediment generation during the Manawatu catchment storm event. Integrating sediment fingerprinting results with spatial datasets and modelling can enhance interpretation of source apportionment results and improve the utility of this information for end-users focused on the spatial targeting of erosion sources for mitigation to reduce downstream sediment impacts.   </p>

scholarly journals Combining colour parameters and geochemical tracers to improve sediment source discrimination in a mining catchment (New Caledonia, South Pacific Islands)

2020 ◽  
Author(s):  
Virginie Sellier ◽  
Oldrich Navratil ◽  
John Patrick Laceby ◽  
Cédric Legout ◽  
Michel Allenbach ◽  
...  
Keyword(s):  
New Caledonia ◽  
Sediment Source ◽  
Sediment Tracing ◽  
Geochemical Properties ◽  
Source Contributions ◽  
The World ◽  
Nickel Mining ◽  
Colour Parameters ◽  
Geochemical Approach ◽  
Variance Explained

Abstract. Over the last century, human activities have induced significant land-cover changes that have accelerated soil erosion processes around the world. In New Caledonia, a French island located in the south-west Pacific Ocean, open-cast nickel mining has raised many concerns regarding its impact on riverine systems (i.e. hyper-sedimentation, overburden) and the island's ecosystems (i.e. flooding, lagoon siltation, water pollution). A sediment tracing study has been conducted to quantify the contribution of mining versus non-mining sub-catchments in one of the first areas exploited for nickel mining, the Thio River catchment (397 km2). Sediment deposited during two cyclonic events (i.e. 2015 and 2017) was collected following a tributary design approach. Source (n = 24) and river sediment (n = 19) samples were analyzed by X-ray fluorescence and spectroscopy in the visible spectra (i.e. 365–735 nm). Four fingerprinting approaches based on (1) colour parameters, (2) geochemical properties, (3) colour parameters coupled with geochemical properties and (4) the entire visible spectrum were tested to estimate sediment source contributions. The results demonstrated that the individual sediment tracing methods based on spectroscopy measurements (i.e. (1) and (4)) did not provide sufficient discrimination between sources. However, the inclusion of colour properties in addition to geochemical parameters (3) provided the highest discrimination between sources (i.e. 92.6 % of source variance explained). Although with a slightly lower discrimination potential (i.e. 83.1 % of variance explained in sources), the geochemical approach (2) provided similar results to those obtained with the colour coupled with geochemical approach (3). In addition, mixed linear models associated with these two approaches have been experimentally validated with artificial mixture samples. The results obtained with model (3) showed that mining source contributions strongly dominated the sediments inputs with a mean contribution of 68 % (SD 25 %) for the 2015 flood event and 88 % (SD 8 %) for the 2017 flood event. These results suggest that catchment management should focus on the contributions of mining tributaries to reduce sediment inputs in the river systems. Therefore, the use of these approaches based on geochemical properties individually (2) and coupled to colour parameters (3) could be extended to other mining catchments of New Caledonia but also to other similar nickel mining catchments around the world (e.g. Australia, Brazil, Dominican Republic, Cuba) to estimate sediment source apportionment.

scholarly journals Agricultural land is the main source of stream sediments after conversion of an African montane forest

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jaqueline Stenfert Kroese ◽  
Pedro V. G. Batista ◽  
Suzanne R. Jacobs ◽  
Lutz Breuer ◽  
John N. Quinton ◽  
...  
Keyword(s):  
Agricultural Land ◽  
Smallholder Farmers ◽  
Lake Victoria ◽  
Management Strategies ◽  
Suspended Sediments ◽  
Large Contribution ◽  
Sediment Sources ◽  
Sediment Yields ◽  
Montane Streams ◽  
Different Sources

Abstract In many parts of Africa, soil erosion is an important problem, which is evident from high sediment yields in tropical montane streams. Previous studies in Kenya pointed to a large contribution from catchments cultivated by smallholder farmers. This led to the hypothesis that unpaved tracks and gullies are the main sediment sources in smallholder agriculture catchments of the highlands of Kenya. The aim of this study was to investigate the sediment sources with sediment fingerprinting to generate the knowledge base to improve land management and to reduce sediment yields. Four main sediment sources (agricultural land, unpaved tracks, gullies and channel banks) and suspended sediments were analysed for biogeochemical elements as potential tracers. To apportion the catchments target sediment to different sources, we applied the MixSIAR un-mixing modelling under a Bayesian framework. Surprisingly, the fingerprinting analysis showed that agricultural land accounted for 75% (95% confidence interval 63–86%) of the total sediment. Channel banks contributed 21% (8–32%), while the smallest contributions to sediment were generated by the unpaved tracks and gullies with 3% (0–12%) and 1% (0–4%), respectively. Erosion management strategies should target agricultural lands with an emphasis on disconnecting unpaved tracks form hillslope source areas to reduce sediment yields to Lake Victoria.

scholarly journals Combining colour parameters and geochemical tracers to improve sediment source discrimination in a mining catchment (New Caledonia, South Pacific Islands)

SOIL ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 743-766
Author(s):  
Virginie Sellier ◽  
Oldrich Navratil ◽  
John Patrick Laceby ◽  
Cédric Legout ◽  
Anthony Foucher ◽  
...  
Keyword(s):  
Pacific Islands ◽  
New Caledonia ◽  
Flood Event ◽  
Colour Properties ◽  
Sediment Source ◽  
Source Discrimination ◽  
Geochemical Tracers ◽  
Geochemical Properties ◽  
Nickel Mining ◽  
Colour Parameters

Abstract. Tracing the origin of sediment is needed to improve our knowledge of hydro-sedimentary dynamics at the catchment scale. Several fingerprinting approaches have been developed to provide this crucial information. In particular, spectroscopy provides a rapid, inexpensive and non-destructive alternative technique to the conventional analysis of the geochemical properties. Here, we investigated the performance of four multi-proxy approaches based on (1) colour parameters, (2) geochemical properties, (3) colour parameters coupled with geochemical properties and (4) the entire visible spectrum to discriminate sediment source contributions in a mining catchment of New Caledonia. This French archipelago located in the south-west Pacific Ocean is the world's sixth largest producer of nickel. Open-cast nickel mining increases soil degradation and the downstream transfer of sediments in river systems, leading to the river system siltation. The sediment sources considered in the current research were therefore sediment eroded from mining sub-catchments and non-mining sub-catchments. To this end, sediment deposited during two cyclonic events (i.e. 2015 and 2017) was collected following a tributary design approach in one of the first areas exploited for nickel mining on the archipelago, the Thio River catchment (397 km2). Source (n=24) and river sediment (n=19) samples were analysed by X-ray fluorescence and spectroscopy in the visible spectra (i.e. 365–735 nm). The results demonstrated that the individual sediment tracing methods based on spectroscopy measurements (i.e. (1) and (4)) were not able to discriminate sources. In contrast, the geochemical approach (2) did discriminate sources, with 83.1 % of variance in sources explained. However, it is the inclusion of colour properties in addition to geochemical parameters (3) which provides the strongest discrimination between sources, with 92.6 % of source variance explained. For each of these approaches ((2) and (3)), the associated fingerprinting properties were used in an optimized mixing model. The predictive performance of the models was validated through tests with artificial mixture samples, i.e. where the proportions of the sources were known beforehand. Although with a slightly lower discrimination potential, the “geochemistry” model (2) provided similar predictions of sediment contributions to those obtained with the coupled “colour + geochemistry” model (3). Indeed, the geochemistry model (2) showed that mining tributary contributions dominated the sediments inputs, with a mean contribution of 68 ± 25 % for the 2015 flood event, whereas the colour + geochemistry model (3) estimated that the mining tributaries contributed 65 ± 27 %. In a similar way, the contributions of mining tributaries were evaluated to 83 ± 8 % by the geochemistry model (2) versus 88 ± 8 % by the colour + geochemistry model (3) for the 2017 flood event. Therefore, the use of these approaches based on geochemical properties only (2) or of those coupled to colour parameters (3) was shown to improve source discrimination and to reduce uncertainties associated with sediment source apportionment. These techniques could be extended to other mining catchments of New Caledonia but also to other similar nickel mining areas around the world.

Assessment of different colour parameters for discriminating potential suspended sediment sources and provenance: A multi-scale study in Luxembourg

Geomorphology ◽  
2010 ◽  
Vol 118 (1-2) ◽  
pp. 118-129 ◽  
Author(s):  
Núria Martínez-Carreras ◽  
Andreas Krein ◽  
Francesc Gallart ◽  
Jean F. Iffly ◽  
Laurent Pfister ◽  
...  
Keyword(s):  
Suspended Sediment ◽  
Sediment Sources ◽  
Multi Scale ◽  
Colour Parameters

scholarly journals Application of quantitative composite fingerprinting technique to identify the main sediment sources in two small catchments of Iran

2010 ◽  
Vol 7 (5) ◽  
pp. 6677-6698 ◽  
Author(s):  
A. Kouhpeima ◽  
S. Feiznia ◽  
H. Ahmadi ◽  
S. A. Hashemi ◽  
A. R. Zareiee
Keyword(s):  
Function Analysis ◽  
Management Strategies ◽  
Source Material ◽  
Limited Resources ◽  
Sediment Source ◽  
Relative Importance ◽  
Sediment Sources ◽  
Reservoir Sediment ◽  
Fingerprinting Technique ◽  
The Mean

Abstract. The targeting of sediment management strategies is a key requirement in developing countries including Iran because of the limited resources available. These targeting is, however hampered by the lack of reliable information on catchment sediment sources. This paper reports the results of using a quantitative composite fingerprinting technique to estimate the relative importance of the primary potential sources within the Amrovan and Royan catchments in Semnan Province, Iran. Fifteen tracers were first selected for tracing and samples were analyzed in the laboratory for these parameters. Statistical methods were applied to the data including nonparametric Kruskal-Wallis test and Differentiation Function Analysis (DFA). For Amrovan catchment three parameters (N, Cr and Co) were found to be not significant in making the discrimination. The optimum fingerprint, comprising Oc, PH, Kaolinite and K was able to distinguish correctly 100% of the source material samples. For the Royan catchment, all of the 15 properties were able to distinguish between the six source types and the optimum fingerprint provided by stepwise DFA (Cholorite, XFD, N and C) correctly classifies 92.9% of the source material samples. The mean contributions from each sediment source obtained by multivariate mixing model varied at two catchments. For Amrovan catchment Upper Red formation is the main sediment sources as this sediment source approximately supplies 36% of the reservoir sediment whereas the dominant sediment source for the Royan catchment is from Karaj formation that supplies 33% of the reservoir sediments. Results indicate that the source fingerprinting approach appears to work well in the study catchments and to generate reliable results.

Monitoring of suspended sediment load and Sediment Sources in a Karst Plateau Catchment of Southwest China.

2020 ◽  
Author(s):  
Tao Peng ◽  
Qianyun Cheng ◽  
Le Cao
Keyword(s):  
Soil Erosion ◽  
Suspended Sediment ◽  
Southwest China ◽  
Sediment Load ◽  
River Sediments ◽  
Primary Source ◽  
Suspended Sediments ◽  
Rainfall Erosivity ◽  
Sediment Sources ◽  
Underground River

<p>The development of karst landforms in southwest China has resulted in surface and underground dual hydrogeological structure. The characteristics of the mechanism of soil erosion and its environmental effects are different from those in non-karst regions. This study aims to monitor sediment load and identify the main sediment source in a typical karst plateau agroforestry catchment, to estimate the relative contribution rates of surface and underground river sediment sources. The results show that the annual sediment transport modulus in catchment is very low (5.1 Mg km<sup>-2</sup> a<sup>-1</sup>) in this carbonate agroforestry catchment compare to deforestation 20 years ago (20 Mg km<sup>-2</sup> a<sup>-1</sup>). Sediment Fluxes in the underground river and surface river account for 19.7% and 80.3% respectively. Soil leakage is an important way but not a main way of soil erosion in typical karst watershed. There is no obvious soil erosion on the hillsides (less than 1 Mg km<sup>-2</sup> a<sup>-1</sup>), but the sediment sources results shows sediment sources of surface and underground river are different in 2017 and 2018, In 2017, it indicate that carbonate surface soil contributes 16.2% and 11.9% of the total suspended sediment to the surface and underground river respectively, and the clastic rock pieces are the primary source of both surface and underground river sediments, 79.5% and 60.8% respectively. Subsurface soil contributes a smaller fraction to the total sediment load, 4.3% to surface rivers and 27.3% to underground rivers. The 137Cs values for some suspended sediments in 2018 were outside the range all of the soil source samples, it attributed to re-mobilization of old sediment stored in karst underground conduits during the deforestation, and these “old sediments” could generate to the surface again when with the rainfall erosivity above 49 J·mm·m<sup>-2</sup>·h<sup>-1</sup>.</p>

scholarly journals Chemical Properties of Heavy Metal-Contaminated Soils from a Korean Military Shooting Range: Evaluation of Pb Sources Using Pb Isotope Ratios

2021 ◽  
Vol 11 (15) ◽  
pp. 7099
Author(s):  
Inkyeong Moon ◽  
Honghyun Kim ◽  
Sangjo Jeong ◽  
Hyungjin Choi ◽  
Jungtae Park ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Contaminated Soils ◽  
Management Strategies ◽  
Chemical Properties ◽  
Heavy Metal Concentration ◽  
Soil Samples ◽  
Shooting Range ◽  
Geochemical Properties ◽  
Mineral Phases

In this study, the geochemical properties of heavy metal-contaminated soils from a Korean military shooting range were analyzed. The chemical behavior of heavy metals was determined by analyzing the soil pH, heavy metal concentration, mineral composition, and Pb isotopes. In total, 24 soil samples were collected from a Korean military shooting range. The soil samples consist of quartz, albite, microcline, muscovite/illite, kaolinite, chlorite, and calcite. Lead minerals, such as hydrocerussite and anglesite, which are indicative of a transformation into secondary mineral phases, were not observed. All soils were strongly contaminated with Pb with minor concentrations of Cu, Ni, Cd, and Zn. Arsenic was rarely detected. The obtained results are indicated that the soils from the shooting range are contaminated with heavy metals and have evidences of different degree of anthropogenic Pb sources. This study is crucial for the evaluation of heavy metal-contaminated soils in shooting ranges and their environmental effect as well as for the establishment of management strategies for the mitigation of environmental risks.

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