Marty Matlock

Prof. Dr. Marty Matlock

orcid

Research Focus & Metrics

Academic Career Length

25Years (2002-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 January 2022 in Journal of Environmental Management
Verified
Journal Article
Open access
PBPrathamesh A. Bandekar
Prathamesh A. Bandekar
BPBen Putman
Ben Putman
GTGreg Thoma
Greg Thoma
MMMarty Matlock
Marty Matlock
Environmental impact associated with production and consumption of pulses in the United States was evaluated using life cycle assessment (LCA). The system boundary was set to cradle-to-grave with a functional unit of 60 g (dry basis) of pulses consumed in a US household. Varieties of pulses modeled in the study included field pea (Pisum sativum), lentil (Lens culinaris), chickpea (Cicer arietinum), and dry bean. Three methods of cooking pulses at the consumer stage tested in the study were cooking in open vessel on electric cooking range (OVC), cooking in stovetop pressure cooker on electric cooking range (SPC), and cooking in electric pressure cooker (EPC). OVC formed the base scenario against which all other scenarios were compared. The environmental impact of pulses varied with type of pulse crop, cooking method, and the batch size. Consumption of approximately 60 g of dry pulses resulted in the greatest environmental impact for OVC. The consumer stage contributed at least 83, 81, 76, 75, and 87 percent for global warming potential (GWP), fossil resource scarcity (FRS), water consumption (WC), freshwater eutrophication (FE), and marine eutrophication (ME), respectively for this scenario. EPC resulted in the greatest decrease in the environmental impact, compared to OVC, for GWP, FRS, FE, and ME for all pulse varieties, which was validated in the uncertainty analysis. SPC, on the other hand, decreased the impact across these categories only for chickpea and dry bean. The uncertainty analysis suggested that the differences associated with cooking methods in the mean land use and water consumption scores of pulses were statistically non-significant. The impact categories were also highly sensitive to the mass of pulses cooked in a batch. Increasing the reference flow in OVC to 1 kg decreased the environmental impact of pulses by 49-87 percent for all impact categories, excluding land use. Overall, the study identified the consumer stage as the hotspot for environmental impact in the supply chain of pulses in the United States. The large contribution of the consumer stage to the overall environmental impact of pulses was attributed to electricity consumption for cooking and associated upstream emissions.

1 January 2008 in Journal of Biological Engineering
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Journal Article
Open access
PDF file
ARAngela D Rodriguez
Angela D Rodriguez
MMMarty Matlock
Marty Matlock
Nutrient management in rivers and streams is difficult due to the spatial and temporal variability of algal growth responses. The objectives of this project were to determine the spatial and seasonal in situ variability of trophic status in the Lake Waco/Bosque River watershed, determine the variability in the lotic ecosystem trophic status index (LETSI) at each site as indicators of the system's nutrient sensitivity, and determine if passive diffusion periphytometers could provide threshold algal responses to nutrient enrichment.

1 April 2003 in Jawra Journal of the American Water Resources Association
Verified
Journal Article
Closed access
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MMMarty Matlock
Marty Matlock
KKKevin Ray Kasprzak
Kevin Ray Kasprzak
GOG. Scott Osborn
G. Scott Osborn

18 January 2023 in Sustainability
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Journal Article
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AHAndrew D Henderson
Andrew D Henderson
AAAnne Asselin-Balençon
Anne Asselin-Balençon
MHMartin C. Heller
Martin C. Heller
JBJasmina Burek
Jasmina Burek
DKDaesoo Kim
Daesoo Kim
OJOlivier Jolliet
Olivier Jolliet
Purpose: Understanding the main factors affecting the environmental impacts of milk production and consumption along the value chain is key towards reducing these impacts. This paper aims to present detailed spatialized distributions of impacts associated with milk production and consumption across the United States (U.S.), accounting for locations of both feed and on-farm activities, as well as variations in impact intensity. Using a Life Cycle Analysis (LCA) approach, focus is given to impacts related to (a) water consumption, (b) eutrophication of marine and freshwater, (c) land use, (d) human toxicity and ecotoxicity, and (e) greenhouse gases. Methods: Drawing on data representing regional agricultural practices, feed production is modelled for 50 states and 18 main watersheds and linked to regions of milk production in a spatialized matrix-based approach to yield milk produced at farm gate. Milk processing, distribution, retail, and consumption are then modelled at a national level, accounting for retail and consumer losses. Custom characterization factors are developed for freshwater and marine eutrophication in the U.S. context. Results and discussion: In the overall life cycle, up to 30% of the impact per kg milk consumed is due to milk losses that occur during the retail and consumption phases (i.e., after production), emphasizing the importance of differentiating between farm gate and consumer estimates. Water scarcity is the impact category with the highest spatial variability. Watersheds in the western part of the U.S. are the dominant contributors to the total water consumed, with 80% of water scarcity impacts driven by only 40% of the total milk production. Freshwater eutrophication also has strong spatial variation, with high persistence of emitted phosphorus in Midwest and Great Lakes area, but high freshwater eutrophication impacts associated with extant phosphorus concentration above 100 µg/L in the California, Missouri, and Upper Mississippi water basins. Overall, normalized impacts of fluid milk consumption represent 0.25% to 0.8% of the annual average impact of a person living in the U.S. As milk at farm gate is used for fluid milk and other dairy products, the production of milk at farm gate represents 0.5% to 3% of this annual impact. Dominant contributions to human health impacts are from fine particulate matter and from climate change, whereas ecosystem impacts of milk are mostly due to land use and water consumption. Conclusion: This study provides a systematic, national perspective on the environmental impacts of milk production and consumption in the United States, showing high spatial variation in inputs, farm practices, and impacts.

1 June 2021 in Journal of the Electrochemical Society
Verified
Journal Article
Closed access
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GQGeletu Qing
Geletu Qing
MAMojtaba Abolhassani
Mojtaba Abolhassani
RDRaheleh Daneshpour
Raheleh Daneshpour
SFShelby L. Foster
Shelby L. Foster
MMMarty Matlock
Marty Matlock
LGLauren F. Greenlee
Lauren F. Greenlee
This work reports on the electrochemical disinfection of natural irrigation water collected from the Waiahole Ditch Irrigation System in Hawaii using a batch cell assembled with titanium electrodes as both anode and cathode. Disinfection experiments were performed by applying a polarity-reversing direct current between the two titanium electrodes. The naturally occurring concentration of chloride in the water was 1.84 mg l −1 and no other chemicals were added. The applied current density was varied between 0 mA cm −2 and 2 mA cm −2 , and the half-period ( T /2) of the polarity-reversing direct current was varied between 5 s and 60 s. The best disinfection performance was achieved at 2 mA cm −2 and T /2 = 10 s, requiring only 5 min of treatment for the complete disinfection of E. coli (4-log reduction). E. coli was inactivated by free chlorine species electrogenerated at the titanium electrodes. Hydrogen peroxide, short-lived oxidants, and direct electron transfer most likely had minor contributions to the disinfection process. During the disinfection experiments, the concentrations of disinfection byproducts (ClO 3 − , CHCl 3 , CHBrCl 2 , CHBr 2 Cl, and CHBr 3 ) were significantly lower than recommendations for drinking water. The titanium electrodes consumed less electrical energy than platinum-coated titanium electrodes because they needed a lower current density to achieve similar disinfection efficiency.

9 October 2021 in Animals
Verified
Journal Article
Open access
PDF file
MMMarty Matlock
Marty Matlock
MCMartin Christie
Martin Christie
GTGreg Thoma
Greg Thoma
Agricultural production systems have been identified as significant sources of anthropogenic impacts across several environmental key performance indicators (KPIs). Livestock husbandry is growing in global importance as the demand for high-quality protein continues to increase. It is therefore imperative to have sustainable intensification technologies, and we describe one such technology. The purpose of this study was to evaluate the performance of Enogen® corn grain compared to conventional feed corn when used as an ingredient in backgrounding and feed yard beef rations using life cycle assessment. The project was conducted in compliance with ISO standards, including a third-party panel review. A series of scenarios were analyzed to evaluate the impacts of boundaries and functional units on the outcomes. The use of Enogen corn as a feed component in beef production showed a quantifiable benefit in terms of the sustainability metrics of primary interest in this study. The gate-to-gate improvements at the feed yard and backgrounding based on full field trial datasets from field trials conducted at Kansas State University and at the University of Nebraska, Lincoln showed 3.4 and 5.8 percent reductions in Global Warming Potential, respectively. It is particularly noteworthy that the improvement in feed conversion ratio at the feed yard results in approximately 6 percent improvement in the four key environmental performance metrics of beef production, which demonstrates potential for the sector to meet its sustainability targets.