Rapid and in situ analysis of metal concentrations in agricultural - PowerPoint PPT Presentation

All About Discovery! ™ New Mexico State University nmsu.edu Rapid and in ‐ situ analysis of metal concentrations in agricultural fields in San Juan County using Portable X ‐ ray fluorescence (PXRF) Gaurav Jha Department of Plant and Environmental Sciences

Basic Principle of PXRF Response to GKM spill Applications in Extension and environmental Outreach sciences All About Discovery! ™ New Mexico State University nmsu.edu

• Soil scientists have long differentiated • Soil scientists have long differentiated soils based on chemical properties. soils based on chemical properties. Curtis Marbut’s Curtis Marbut’s Normal Soil concept Normal Soil concept Ped alfe r Pedo ca l All About Discovery! ™ New Mexico State University nmsu.edu

• Historically, many chemical determinations were made Rapid via titration or colorimetry. • More recently, lab based instruments have offered Large greater accuracy Cost number Effective of • ICP-AES/MS samples • AAS All About Discovery! ™ New Mexico State University nmsu.edu

The colors we see! http://www.sun.org/encyclopedia/electromagnetic-spectrum All About Discovery! ™ New Mexico State University nmsu.edu

Working Principle of PXRF Activation of Sample Fluorescence X-Ray Tube Excitation http://www.equipcoservices.com/support/tutorials/introduction-to-xrf-spectrometry/ https://www.olympus-ims.com/en/xrf-xrd/delta-handheld/delta- mining/#!cms[tab]=%2Fxrf-xrd%2Fdelta-handheld%2Fdelta- mining%2Fapplications Results Capture Spectrum All About Discovery! ™ New Mexico State University nmsu.edu https://www.olympus-ims.com/en/applications/portable-xrf-technology-archaeometry- authentication-conservation-art-objects/

Specifications for GKM sample analysis • X Ray tube operated at 10-40 keV. Not an active source of radiations. • Standards: Stainless steel ‘316’ alloy chip • 16.13% Cr • 1.78% Mn • 68.76% Fe • 10.42% Ni • 0.20% Cu • 2.10% Mo • Verified by NIST soil standards • Scan time- 90 seconds for three beams (30 seconds per beam) • Instrument is operated in proprietary standard configurations : 1. Geochem mode 2. Soil mode All About Discovery! ™ New Mexico State University 3. Mining mode nmsu.edu

Note-PXRF reports total elemental concentration; not ionic species (e.g. Fe +2 vs. Fe +3 ) or compounds (gypsum, calcite, etc.) All About Discovery! ™ New Mexico State University nmsu.edu

Advantages • Portable • Simple, non-destructive analysis • Rapid (90 sec scan) • Multi-element analysis • Low limit of detection and wide dynamic range Disadvantages • Cannot determine H,C or Na • Soil heterogeneity (example Fe and Mn concretions) All About Discovery! ™ New Mexico State University nmsu.edu

Basic Principle of PXRF Applications in environmental sciences All About Discovery! ™ New Mexico State University nmsu.edu

Site specific proxy-determinations of soil parameters via PXRF • Soil cation exchange capacity (CEC) • Soil pH • Soil salinity On-site metal determination via PXRF • Heavy metal content • Sediment and soil spatial analysis • Plant tissue analysis • Water analysis All About Discovery! ™ New Mexico State University nmsu.edu

Proxy-determinations of soil CEC via PXRF • CEC is directly associated with soil fertility. • Lab methods are very accurate but arduous. http://scienceofagriculture.org/ch-cation.php • In-situ prediction of soil CEC to develop a predictive model based on enhanced lab based data. R 2 = 0.908 Sharma et al. (2015) All About Discovery! ™ New Mexico State University nmsu.edu

Proxy-determinations of soil pH via PXRF • PXRF cannot read Hydrogen ion directly. • Soil system pH is commonly associated with https://cosmosmagazine.com/climate/what-happens-if-permafrost- disappears other elements. Alkaline system-Ca, Mg Acidic system-Al, Fe • These elements can be used as a proxy for pH determination specially where traditional https://maui-mike.smugmug.com/keyword/lithified%20sand%20dunes/ sampling is not possible- frozen and lithified soils. All About Discovery! ™ New Mexico State University nmsu.edu https://www.uidaho.edu/cals/soil-and-water- systems/research/pedology-laboratory/fosberg-monoliths

Basic Principle of PXRF Response to GKM spill Applications in environmental sciences All About Discovery! ™ New Mexico State University nmsu.edu

All About Discovery! ™ New Mexico State University nmsu.edu

All About Discovery! ™ New Mexico State University nmsu.edu https://i.kinja-img.com/gawker- edia/image/upload/c_ scale,fl_progressive,q_80,w_800/13755 78641640044175.jpg

Gold King Mine Spill- A case study using PXRF • Monitor selected metal concentrations in agricultural fields and crop grown within the Animas and San Juan River watershed. • Characterize spatial variability of selected metals All About Discovery! ™ New Mexico State University nmsu.edu

All About Discovery! ™ New Mexico State University nmsu.edu

Colorado New Mexico Sampling locations P Aztec F Shiprock V Farmington Bloomfield Sampling sites with increasing distance from the GKM (Colorado and NM border through Shiprock) V P F All About Discovery! ™ New Mexico State University nmsu.edu Vegetables Forage (Alfalfa) Pasture (Grass)

On-site Metal determination for soil spatial analysis All About Discovery! ™ New Mexico State University nmsu.edu Total Arsenic concentration (parts per million)

What we observed? All About Discovery! ™ New Mexico State University nmsu.edu

Average total metal(loid) concentrations (mg kg -1 ) in fields irrigated by Animas river water Concentration Concentration Concentration RSL (mg kg -1 ) in (mg kg -1 ) in (mg kg -1 ) in Metal (mg kg -1 ) Pasture land Forage land Vegetable Field Arsenic 7.07 7.19 6.92 7.13 Lead 400 83.28 48.09 17.50 Calcium - 10450 16609 37006 Zinc 2300 223.46 116.64 71.47 Copper 310 38.98 29.43 21.35 Manganese 180 874.92 545.04 312.84 All About Discovery! ™ Iron 5500 New Mexico State University 23838 23160 22860 nmsu.edu

Spatial distribution of Arsenic in agricultural fields Total Arsenic concentration (parts per million) RSL-7.07 mg kg -1 Pasture grass Forage (alfalfa) Vegetables 14.1 hectares 3.04 hectares 1.27 hectares Aztec Farmington Shiprock All About Discovery! ™ New Mexico State University nmsu.edu

Spatial distribution of Manganese in agricultural fields Total Manganese concentration (parts per million) RSL-180 mg kg -1 Pasture grass Forage (alfalfa) Vegetables 14.1 hectares 3.04 hectares 1.27 hectares Aztec Farmington Shiprock All About Discovery! ™ New Mexico State University nmsu.edu

Soil Arsenic and Plant growth • Environmental toxin. • Inhibits root proliferation and extensions. • Slows expansion and biomass accumulation. (Finnegan et al, 2012) https://edu.glogster.com/glog/arse nic/2dxuahjh3rg Hyperaccumulation Into Food chain Keratosis http://arsenic-33.narod.ru/groundwater-arsenic- https://www.aljazeera.com/indepth/features/2016/01/indias-arsenic-belt- contamination-in-west-bengal-india.html water-project-brings-relief-160128090612395.html All About Discovery! ™ New Mexico State University nmsu.edu

CORN Corn Cob Guideline value Metal Conc. Metal (mg/kg) (mg/kg) Al 7-3410 35 As 1.7 ND Cr N/A ND Fe 48 82 Leaves 300 Mn 50 Soil Pb 10 3 Zn 150 78 Ca N/A 6334 Designed by-Mathews A. 30 Cu 13 All About Discovery! ™ New Mexico State University nmsu.edu

WATER MELONS Metal Conc. Guideline value Metal (mg/kg) (mg/kg) Melon Leaves 406 Al 7-3410 0.5 As 1.7 ND Cr N/A 48 387 Fe Soil Designed by-Mathews A. 30 Mn 300 3 Pb 10 32 Zn 150 N/A 51955 Ca 8 Cu 30 All About Discovery! ™ New Mexico State University nmsu.edu

HONEYDEW SQUASH Guideline value Metal Conc. Metal (mg/kg) (mg/kg) Honeydew Al 7-3410 397 Leaves As 1.7 0.9 Cr N/A ND 48 Fe 355 Designed by-Mathews A. Soil Mn 300 33 Pb 10 ND Zn 150 33 Ca N/A 65650 Cu 30 10 All About Discovery! ™ New Mexico State University nmsu.edu

Basic Principle of PXRF Response to GKM spill Applications in Extension and environmental Outreach sciences All About Discovery! ™ New Mexico State University nmsu.edu

Scanning contaminated river sediment samples using VisNIR and PXRF at Indian Institute of Technology (India) All About Discovery! ™ New Mexico State University nmsu.edu

Conclusions • Portable X-Ray Fluorescence is a rapid, in-situ and non-destructive technique for site specific proxy determination of soil properties and total concentration of metal content. • Exceeded As and Mn total concentration at some of the hotspots in the fields across Animas and San Juan watershed did not correspond to the increased concentration in leaf tissue of plants. • Metal analysis using PXRF helped to respond quickly when GKM spill happened and also to reach the farmers and growers at teach-in, radio talks and through factsheets. All About Discovery! ™ New Mexico State University nmsu.edu