College of Behavioral & Social Sciences

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The collections in this community comprise faculty research works, as well as graduate theses and dissertations..

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    Evaluating the Impact of the 2020 Iowa Derecho on Corn and Soybean Fields Using Synthetic Aperture Radar
    (MDPI, 2020-11-26) Hosseini, Mehdi; Kerner, Hannah R.; Sahajpal, Ritvik; Puricelli, Estefania; Lu, Yu-Hsiang; Lawal, Afolarin Fahd; Humber, Michael L.; Mitkish, Mary; Meyer, Seth; Becker-Reshef, Inbal
    On 10 August 2020, a series of intense and fast-moving windstorms known as a derecho caused widespread damage across Iowa’s (the top US corn-producing state) agricultural regions. This severe weather event bent and flattened crops over approximately one-third of the state. Immediate evaluation of the disaster’s impact on agricultural lands, including maps of crop damage, was critical to enabling a rapid response by government agencies, insurance companies, and the agricultural supply chain. Given the very large area impacted by the disaster, satellite imagery stands out as the most efficient means of estimating the disaster impact. In this study, we used time-series of Sentinel-1 data to detect the impacted fields. We developed an in-season crop type map using Harmonized Landsat and Sentinel-2 data to assess the impact on important commodity crops. We intersected a SAR-based damage map with an in-season crop type map to create damaged area maps for corn and soybean fields. In total, we identified 2.59 million acres as damaged by the derecho, consisting of 1.99 million acres of corn and 0.6 million acres of soybean fields. Also, we categorized the impacted fields to three classes of mild impacts, medium impacts and high impacts. In total, 1.087 million acres of corn and 0.206 million acres of soybean were categorized as high impacted fields.
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    Assessing within-Field Corn and Soybean Yield Variability from WorldView-3, Planet, Sentinel-2, and Landsat 8 Satellite Imagery
    (MDPI, 2021-02-26) Skakun, Sergii; Kalecinski, Natacha I.; Brown, Meredith G. L.; Johnson, David M.; Vermote, Eric F.; Roger, Jean-Claude; Franch, Belen
    Crop yield monitoring is an important component in agricultural assessment. Multi-spectral remote sensing instruments onboard space-borne platforms such as Advanced Very High Resolution Radiometer (AVHRR), Moderate Resolution Imaging Spectroradiometer (MODIS), and Visible Infrared Imaging Radiometer Suite (VIIRS) have shown to be useful for efficiently generating timely and synoptic information on the yield status of crops across regional levels. However, the coarse spatial resolution data inherent to these sensors provides little utility at the management level. Recent satellite imagery collection advances toward finer spatial resolution (down to 1 m) alongside increased observational cadence (near daily) implies information on crops obtainable at field and within-field scales to support farming needs is now possible. To test this premise, we focus on assessing the efficiency of multiple satellite sensors, namely WorldView-3, Planet/Dove-Classic, Sentinel-2, and Landsat 8 (through Harmonized Landsat Sentinel-2 (HLS)), and investigate their spatial, spectral (surface reflectance (SR) and vegetation indices (VIs)), and temporal characteristics to estimate corn and soybean yields at sub-field scales within study sites in the US state of Iowa. Precision yield data as referenced to combine harvesters’ GPS systems were used for validation. We show that imagery spatial resolution of 3 m is critical to explaining 100% of the within-field yield variability for corn and soybean. Our simulation results show that moving to coarser resolution data of 10 m, 20 m, and 30 m reduced the explained variability to 86%, 72%, and 59%, respectively. We show that the most important spectral bands explaining yield variability were green (0.560 μm), red-edge (0.726 μm), and near-infrared (NIR − 0.865 μm). Furthermore, the high temporal frequency of Planet and a combination of Sentinel-2/Landsat 8 (HLS) data allowed for optimal date selection for yield map generation. Overall, we observed mixed performance of satellite-derived models with the coefficient of determination (R2) varying from 0.21 to 0.88 (averaging 0.56) for the 30 m HLS and from 0.09 to 0.77 (averaging 0.30) for 3 m Planet. R2 was lower for fields with higher yields, suggesting saturation of the satellite-collected reflectance features in those cases. Therefore, other biophysical variables, such as soil moisture and evapotranspiration, at similar fine spatial resolutions are likely needed alongside the optical imagery to fully explain the yields.
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    An Investigation of Maize at Four Sites (LA 20241, LA 38597, LA 112766, and LA 131202) in Eddy County, New Mexico
    (2022) Granados, Suzan Marie; Palus, Matthew; Hockersmith, Kelly; Anthropology; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)
    A topic of interest for many New Mexico archaeologists is the introduction and domestication of maize in the Southwest. This investigation adds to the archaeological record of when and to what extent maize was integrated into the subsistence of southeastern New Mexico prehistoric groups. Currently, the accepted date range for the introduction of maize in southeast New Mexico is 500–200 BC (Vierra 2020). Preliminary results of this investigation indicate the presence of maize in the Permian Basin of southeastern New Mexico dating to 2501 +/-125 calibrated (cal) BC; 1000 years prior to the earliest maize site recorded in the archaeological record for the area. The significance of this early date is twofold 1) the Middle Archaic date in comparison to other old maize sites in the area; and 2) the Middle Archaic date challenges the currently accepted migration patterns of maize into southeastern New Mexico. Dr. Jonathan Mabry’s 2008 study suggest that maize was introduced no later than 2100 BC in the southwest; however, Mabry states that maize use did not become common in the North American southwest until around 1400 BC (Mabry 2008). This investigation focuses on a case study of four sites, LA 20241, LA 38597, LA 112766, and LA 131202, in what is now known as Eddy County within the Permian Basin of southeastern New Mexico. I chose these sites because of my direct involvement in the data recovery field investigation and curation. I spent several weeks directing the excavation at Sites LA 112766 and LA 131202. and served as the laboratory manager for processing the artifact collections and flotation samples for all four sites. Evidence recovered from these four archaeological sites in southeast New Mexico, specifically Eddy County, suggest that maize use was low through the Archaic period and did not increase until AD 700–850 (Diehl 1996, Miller 2016, Railey 2016). This thesis demonstrates that maize was present much earlier in the archaeological record than previously reported for southeastern New Mexico. The analysis of macrobotanical, phytolith, and starch remains, and ceramics, and radiocarbon dates from cultural features at Sites LA 20241, LA 38597, LA 112766 and LA 131202 were examined to answer the question: when and to what extent was maize integrated into the subsistence of southeastern New Mexico prehistoric groups? A radiocarbon date from Feature 5, at Site LA 112766, indicates evidence of maize as early as 2501 +/-125 calibrated (cal) BC. Additionally, radiocarbon dates identified six Late Archaic features and thirteen Early Formative features that contained maize residue collectively from Sites LA 20241, LA 38597, LA 112766, and LA 131202. Lastly, Site LA 20241 had a single Late Formative feature that yielded maize residue. This thesis will focus on the signature of maize in the archaeological record of Archaic and Formative groups of southeastern New Mexico.