12 research outputs found
Establishing a Vegetative Cap for Sustainable Stabilization of Copper Contaminated Soils in Torch Lake, Michigan
Extensive mining activities during the late 19th and early 20th centuries in the Upper Peninsula, Michigan have resulted in a number of contaminated sites with mine tailings. Several million metric tons of mine tailings were generated during the peak of copper (Cu) mining activities in this region. These tailings are called “stamp sands” because they were generated by crushing native Cu containing rocks, by a process known as stamping. The stamp sands were discharged into Lake Superior, other interior lakes and their shorelines, converting these areas into vast, fallow lands. The Cu contaminated stamp sands are being eroded back into the lakes, severely affecting the benthic community. The stamp sands are slightly alkaline in nature, have very low organic matter content and are highly deficient in nutrients, such as nitrogen, phosphorus and carbon. The Gay and Hubbell/Tamarack site stamp sand sites have about 50 and 19 times higher total Cu concentration compared to a normal agricultural soil, respectively. Biosolids collected from the local Portage Lake Water and Sewage Authority (PLWSA) and locally available compost was used as source of nutrients for the plants. The goal was to grow the oil seed crops camelina (Camelina sativa) and field pennycress (Thlaspi arvense) on these marginal lands, which can serve the dual purpose of producing feedstock for biofuels and reducing erosion of the Cu contaminated soils into the lakes. We conducted: i) laboratory incubation study to evaluate the geochemical fate of copper and soil nutrient profile in contaminated stamp sands with the addition of biosolids and compost amendments, ii) greenhouse column study to evaluate the effect of compost addition and plant cover (camelina, field pennycress) on the control of stamp sand erosion and fate and distribution of Cu, iii) field simulation study to evaluate the effect of plant cover (camelina, field pennycress) on control of stamp sand erosion and to evaluate the quality of biofuels from the biofuel feedstock (camelina, field pennycress) grown in stamp sands, and iv) door to door survey of the Torch Lake Township in Upper Peninsula of MI to get the opinions of local people about starting our project of reducing stamp sand erosion and biofuel feedstock production in the Torch Lake area. Results from this study will help in the (1) development of a novel technique for the establishment of a sustainable vegetative cap to prevent erosion of stamp sands into the Torch Lake which will serve as a model for the re-vegetation of other metal-impacted areas and (2) development of a novel biodiesel feedstock production system in marginal lands using oilseed crops, which is inexpensive, sustainable and regionally-appropriate
Growing biofuel feedstocks in copper-contaminated soils of a former superfund site
Copper mining in the Upper Peninsula of Michigan in the mid-19th century generated millions of tons of mining waste, called stamp sand, which was deposited into various offshoots of Lake Superior. The toxic stamp sand converted the area into barren, fallow land. Without a vegetative cover, stamp sand has been eroding into the lakes, adversely affecting aquatic life. Our objective was to perform a greenhouse study, to grow cold-tolerant oilseed crops camelina (Camelina sativa) and field pennycress (Thlaspi arvense) on stamp sand, for the dual purpose of biofuel production and providing a vegetative cover, thereby decreasing erosion. Camelina and field pennycress were grown on stamp sands in columns, using compost to supply nutrients. A greenhouse study in wooden panels was also done to evaluate the effectiveness of camelina in reducing erosion. Results show that camelina significantly reduced erosion and can also be used commercially for generating biodiesel. A 25-fold reduction in Cu content in the surface run-off was observed in the panels with camelina compared to those of the control. Stamp sand-grown camelina seeds contained 20% and 22.7% oil and protein respectively, and their fatty acid composition was similar to previous studies performed on uncontaminated soils
Impact of EDDS Dosage on Lead Phytoextraction in Contaminated Urban Residential Soils
Lead (Pb) contamination in soils of residential properties due to peeling and chipping of Pb-based paint can cause human health problems. Phytoextraction is a green technology that has the potential to remediate soil Pb. The efficiency of phytoextraction is dependent on the geochemical forms of Pb in soil. A biodegradable chelating agent, ethylenediaminedisuccinic acid (EDDS), was previously shown to enhance Pb removal by facilitating phytoextraction. In this study, EDDS was tested at various concentrations for its potential in mobilizing Pb in urban residential soils in Jersey City, New Jersey, and San Antonio, Texas. Results show that the concentrations of plant-available forms of Pb increased with the increasing dosage of EDDS from 2 to 30 mmol/L. The addition of EDDS at 30 mmol/L resulted in the conversion of up to 61.2% and 68.9% of the total Pb to plant-available forms in Jersey City and San Antonio soils, respectively. Further analysis showed that, after EDDS application, carbonate-bound Pb, oxide-bound Pb, organic-bound Pb, and residual silicate-bound Pb were transformed to plant-available forms. Higher doses of EDDS performed better than lower doses in transforming soil Pb forms, especially for the oxide-bound Pb. Strong correlations between Pb concentrations measured on-site using a portable X-ray Fluorescence Analyzer (p-XRF) and those obtained in the laboratory using Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES) confirmed that p-XRF is a reliable rapid, convenient technology to measure Pb levels in situ
Harnessing genetic potential of wheat germplasm banks through impact-oriented-prebreeding for future food and nutritional security
The value of exotic wheat genetic resources for accelerating grain yield gains is largely unproven and unrealized. We used next-generation sequencing, together with multi-environment phenotyping, to study the contribution of exotic genomes to 984 three-way-cross-derived (exotic/elite1//elite2) pre-breeding lines (PBLs). Genomic characterization of these lines with haplotype map-based and SNP marker approaches revealed exotic specific imprints of 16.1 to 25.1%, which compares to theoretical expectation of 25%. A rare and favorable haplotype (GT) with 0.4% frequency in gene bank identified on chromosome 6D minimized grain yield (GY) loss under heat stress without GY penalty under irrigated conditions. More specifically, the ‘T’ allele of the haplotype GT originated in Aegilops tauschii and was absent in all elite lines used in study. In silico analysis of the SNP showed hits with a candidate gene coding for isoflavone reductase IRL-like protein in Ae. tauschii. Rare haplotypes were also identified on chromosomes 1A, 6A and 2B effective against abiotic/biotic stresses. Results demonstrate positive contributions of exotic germplasm to PBLs derived from crosses of exotics with CIMMYT’s best elite lines. This is a major impact-oriented pre-breeding effort at CIMMYT, resulting in large-scale development of PBLs for deployment in breeding programs addressing food security under climate change scenarios
Effects of biosolids and compost amendment on chemistry of soils contaminated with copper from mining activities
Several million metric tons of mining wastes, called stamp sands, were generated in the Upper Peninsula of Michigan during extensive copper (Cu) mining activities in the past. These materials, containing large amounts of Cu, were discharged into various offshoots of Lake Superior. Due to evidences of Cu toxicity on aquatic organisms, in due course, the materials were dredged and dumped on lake shores, thus converting these areas into vast, fallow lands. Erosion of these Cu-contaminated stamp sands back to the lakes is severely affecting aquatic life. A lack of uniform vegetation cover on stamp sands is facilitating this erosion. Understanding the fact that unless the stamp sands are fertilized to the point of sustaining vegetation growth, the problem with erosion and water quality degradation will continue, amending the stamp sands with locally available biosolids and composts, was considered. The purpose of the reported study was to assess potential effects of such organic fertilizer amendments on soil quality. As the first step of a combined laboratory and greenhouse study, a 2-month-long incubation experiment was performed to investigate the effects of biosolids and compost addition on the soil nutrient profile of stamp sands and organic matter content. Results showed that both biosolids and compost amendments resulted in significant increase in nitrogen and phosphorus concentrations and organic matter contents of stamp sands. Sequential extraction data demonstrated that Cu was mostly present as bound forms in stamp sands, and there was no significant increase in the plant available fraction of Cu because of fertilizer application
Community response to a sustainable restoration plan for a superfund site
© 2018, Springer-Verlag GmbH Germany, part of Springer Nature. Large-scale copper (Cu) mining activities in Michigan’s Upper Peninsula produced millions of metric tons of mining wastes also known as stamp sands. The stamp sands containing high concentrations of Cu were disposed of into several lakes connected to the Lake Superior. Eventually, as aquatic organisms in these lakes started to exhibit toxicity symptoms, the stamp sands were dredged and discarded on the lake shores. Consequently, these areas turned into degraded, marginal lands and were collectively classified as a Torch Lake Superfund site by the US EPA. Due to the lack of vegetative cover, the Cu-rich stamp sands eroded into the lakes, affecting the aquatic life. To alleviate this issue, a sustainable restoration plan (SRP) was developed and tested in a greenhouse environment prior to field implementation. Cold-tolerant oilseed crops, camelina (Camelina sativa) and field pennycress (Thlaspi arvense), were grown on compost-fertilized stamp sands, which reduced soil erosion by acting as a vegetative cap. Oilseed plants produced normal yield, demonstrating their potential utilization as biofuel feedstock. Prior to implementing the SRP in field-scale in the Torch Lake Superfund site, a public opinion survey of the local community was conducted to understand the views of residents. Door-to-door survey was performed in July–August 2015, which yielded a response rate of 68.1%. Results showed that residents were generally concerned with stamp sand erosion into the Torch Lake and were overwhelmingly supportive of the SRP, which would not only provide environmental benefits but could boost the local economy via biofuel production. To gauge the general environmental awareness of the respondents, the survey included questions on climate change. Most of the respondents acknowledged that climate change is real and anthropogenically mediated. Having college education and a relatively high annual household income showed a positive and significant correlation with climate change awareness
Correlation of Phosphorus Adsorption with Chemical Properties of Aluminum-Based Drinking Water Treatment Residuals Collected from Various Parts of the United States
Over the past several decades, the value of drinking water treatment residuals (WTRs), a byproduct of the coagulation process during water purification, has been recognized in various environmental applications, including sustainable remediation of phosphorus (P)-enriched soils. Aluminum-based WTRs (Al-WTRs) are suitable adsorbent materials for P, which can be obtained and processed inexpensively. However, given their heterogeneous nature, it is essential to identify an easily analyzable chemical property that can predict the capability of Al-WTRs to bind P before soil amendment. To address this issue, thirteen Al-WTRs were collected from various geographical locations around the United States. The non-hazardous nature of the Al-WTRs was ascertained first. Then, their P adsorption capacities were determined, and the chemical properties likely to influence their adsorption capacities were examined. Statistical models were built to identify a single property to best predict the P adsorption capacity of the Al-WTRs. Results show that all investigated Al-WTRs are safe for environmental applications, and oxalate-extractable aluminum is a significant indicator of the P adsorption capacity of Al-WTRs (p-value = 0.0002, R2 = 0.7). This study is the first to report a simple chemical test that can be easily applied to predict the efficacy of Al-WTRs in binding P before their broadscale land application
Wood mulch coated with iron-based water treatment residuals for the abatement of metals and phosphorus in simulated stormwater runoff
Laboratory-scale batch and flow-through studies evaluated the performance of iron-based water treatment residuals (Fe-WTR) coated wood mulch for removing two types of urban stormwater runoff pollutants i.e., toxic heavy metals (Cu, Zn, and Pb) and the nutrient, phosphorus (P). Fe-WTR is an industrial waste byproduct generated from the treatment of drinking water, primarily comprising amorphous iron (hydr)oxides. The Fe-WTR particles had a large surface area and were non-hazardous, as indicated by toxicity characteristic leaching procedure (TCLP) and synthetic precipitation leaching procedure (SPLP) tests. Batch studies of WTR-coated mulch loaded with simulated urban stormwater fixed pollutant concentrations showed fast (\u3c5 \u3emin), and nearly complete removal of Cu, Zn, and Pb, contrasting with lower and incomplete removal of P. Temperature and pH affected the removal process only for Zn, with increasing pH improving the removal. Flow-through column studies with 5.1 and 10.2-cm filtration bed depths were performed using simulated stormwater. Coated mulch performed better than uncoated mulch for all pollutants and for both bed depths. In the 10.2 cm bed, 21% to 25% higher reductions were observed for metals and 8% higher reduction for P using coated mulch relative to uncoated mulch. The increases were statistically significant in all cases, with p \u3c 0.001 for the 10.2 cm bed. This study demonstrates that Fe-WTR coated wood mulch can serve as an innovative adsorbent media for urban stormwater treatment. Moreover, this application finds a beneficial way of reusing Fe-WTR as a value-added product, saving the cost of its disposal in landfills
Atypical Anaphylactic Reaction to Patent Blue During Sentinel Lymph Node Biopsy for Breast Cancer
This paper provides new estimates of capital inputs in the Chinese economy. Estimates are made for the total economy (1953-2003), for the industrial sector (1978-2003) and for the manufacturing sector (1985-2003). The estimates for industry and manufacturing are broken down by thirty regions. The main contribution of this paperlies in constructing hitherto unvailable estimates of capital inputs at the level of Chinese regions. The paper makes a systematic attempt to apply SNA concepts to the estimation of Chinese capital inputs, according to the Perpetual Inventory Method. It makes a clear distinction between capital services and wealth capital stocks. After a general discussion of theoretical issues in capital measurement, the paper provides a detailed analysis of the relevant Chinese statistical concepts and data. It goes on to discuss previous capital estimates in the light of the modern conceptual and theoretical discussions. It ends with an explanation of the procedures followed in constructing the national and regional capital input series.