The CASNR L.I.N.K.S Newsletter: Learning Innovation Network for K-12 Schools, Edition 9, October 2022

The purpose of this L.I.N.K.S. newsletter is to provide a monthly update of opportunities and resources for K-12 schools to connect with the University of Nebraska\u27s CASNR Food, Energy, Water, and Societal Systems (FEWS²) programs and partners. Included in this edition: K-12 Partners website is live Curriculum and classroom resources for all levels Eye on curriculum and resources Idena Nebraska Ag Expo career exploration event Teacher opportunities Link to list of new partnerships Ask an expert Students experiences: Student internship opportunities with USDA NRCS and Scholarships available Eye on CASR research: Commodity marketing for high school students Send your students to campus Success stories: Flying squirrel boxes at Lincoln Northeast High Schoo

The CASNR L.I.N.K.S Newsletter: Learning Innovation Network for K-12 Schools, Edition 10, November 2022

The purpose of this L.I.N.K.S. newsletter is to provide a monthly update of opportunities and resources for K-12 schools to connect with the University of Nebraska\u27s CASNR Food, Energy, Water, and Societal Systems (FEWS²) programs and partners. Included in this edition: Curriculum and classroom resources for all levels K-12 Partners website is live Eye on curriculum and resources Teacher opportunities Link to list of new partnerships Ask an expert Eye on CASNR research: Yu Feng Ge Student experiences Send your students to campus: Husker weekday visit Success stories: Art, science, and ag combine in a mural and Lincoln Northeast High Schoo

Preliminary Identification of Ground-Water Nitrate Sources Using Nitrogen and Carbon Stable Isotopes, Kansas

Increasing nitrate-N in ground water is a problem in many areas with limited ground-water supplies, such as west-central Kansas. However, potential sources of nitrate-N are not known. Nitrate-N concentrations in ground water in the Hays study area in Ellis County, west-central Kansas, range from 0.9 to 26 mg/L. The δ15N signatures of the ground waters are more enriched (+16.8 to +28.7‰) than those of the soils (+8.4 to +13.7‰), strongly suggesting that nitrogen sources are not from mineralized and labile nitrogen present in the unsaturated zone. In this study, nitrate-N values greater than the U.S. EPA drinking water limit of 10 mg/L occur with δ15N values of greater than +10‰. This relationship between high nitrate-N concentrations and enriched δ15N values (greater than +10‰) in ground water has been observed in other studies in Kansas and is usually related to a human- and/or animal-waste source. Soil cores collected near municipal wells had mean total nitrogen values of 1.2-15 mg/kg. Increased δ15N with depth in several of the cores suggests that microbial mineralization, denitrification, or volatilization processes caused the enriched δ15N signatures. Decreasing total nitrogen and nitrate-N values with depth also help support the idea of microbial processes. Stable carbon isotopes provide supporting evidence that soils are not a major contributor to the observed nitrate-N concentration in the ground water. δ13C values of the dissolved organic carbon (DOC) in soils generally were more enriched (-11.6 to -18.8‰) while corresponding ground-water δ13C values were more depleted (-19.9 to -22.2‰), suggesting that the source of the DOC in ground water is not from the soils

Evaluation Drip Irrigation Method for Hot Peppers Production Using Roof-top Rain Water in Home Garden Irrigation at Water Scarce Area of Fadis, Estern Oromia Region

Existing fresh water resources are subjected to an ever-increasing pressure due to extensive agricultural water demand for irrigated lands. A long-term perspective in shortage of fresh water resources, especially in arid and semi-arid area, highlights an urgent solution for innovative irrigation technologies and agricultural water management strategies. The experiment was conducted at Fadis agricultural research center farm in Boko station. The aim of the study was to evaluate performance of hot pepper varieties under drip irrigation system using water harvested from roof top on growth and yield parameters. The experiment was arranged in RCBD, replicated three times. Three hot pepper varieties namely: mareko fana, malka awaze and local check were used as experimental crop. The result on yield and plant height showed that there was significance difference (P<0.05) between mareko fana and malka awaze with local check hot pepper varieties when irrigated with equal water application. In case of hot pepper number of main branch, there was significant difference (p<0.05) between each hot pepper varieties under drip irrigation system. Number of fruit per plant, had significance difference between local check and malka awaze. The yield obtained for both mareko fana and melka awaze hot pepper varieties were satisfactory, therefore both varieties were recommended for further use under drip irrigation system in the study area and other similar agro ecologies. Keywords: Crop water requirement; drip irrigation; hot pepper performance. DOI: 10.7176/JRDM/59-02 Publication date:September 30th 201

Precipitation Event Size Controls on Long-Term Abundance of \u3ci\u3eOpuntia Polyacantha\u3c/i\u3e (Plains Prickly-Pear) in Great Plains Grasslands

Opuntia polyacantha Haw. (plains prickly-pear) is a common cactus in the Great Plains of North America. We used two data sets, from Montana and Colorado, to test the hypothesis that there is a range of precipitation event sizes upon which O. polyacantha specializes. Events smaller than this range (\u3e2 to ≤6 mm) do not moisten sufficient soil to be utilized, and larger events have negative effects on the status of O. polyacantha because they favor the development of taller and denser grass canopies. Multiple regressions of either green cladode density (northern mixed prairie) or O. polyacantha frequency (shortgrass steppe) with precipitation event sizes indicated negative effects of large precipitation events on the yearly changes in the either density or frequency of O. polyacantha. We suggest that weather conditions in the Great Plains may cause O. polyacantha to be controlled almost entirely by light competition from grasses and other negative biotic effects

Improved production systems for common bean in south-central Uganda: I. Liddugavu soil, II. Limyufumyufu soil

Common bean (Phaseolus vulgaris L.) is the most important source of dietary protein in Uganda but current grain yields are extremely low. Beans are produced on a variety of soils in south-central Uganda but the two most important soils for bean production are the highly weathered Limyufumyufu (Ferralsol) and the relatively fertile Liddugavu (Phaeozem) soils. These two soils vary in level of pH and fertility and therefore must be managed appropriately. Beans managed under conventional systems have a yield gap of about 75% due to poor agronomic practices, soil infertility, lack of seed from improved cultivars, moisture stress, weed competition, and damage caused by pests and diseases. The objective of this study was to compare the productivity and net profitability of four bean cultivars grown under three management systems on Limyufumyufu and Liddugavu soils in Masaka District, Uganda. The experiment was designed as a randomized complete block in a split-plot arrangement. Management system was the whole-plot factor and included the Conventional Farmer (CFS), Improved Farmer (IFS), and High Input systems (HIS). Management systems differed for seed fungicide treatment (no vs. yes), seeding density (10 vs. 20 seed m-2), plant configuration (scatter vs. rows), fertilizer applications (P, K, Ca, Mg, Zn, and S), rhizobium inoculation (no vs. yes), pesticide applications (no vs. yes), and frequency and timing of weeding. Subplots were four bush type common bean cultivars that differed for resistance to foliar pathogens. Increasing management level, independent of rainy season, and planting bean cultivars tolerant to common bean diseases improved bean grain yield. On the Limyufumyufu soil, there were only grain yield differences between cultivars in the 2015A season; NABE 14 had the greatest grain yield (772 kg ha-1), 168% greater than NABE 15 (288 kg ha-1). The HIS with NABE 14 (1274 kg ha-1), the HIS with NABE 4 (1225 kg ha-1), and the IFS with NABE 14 (1025 kg ha-1) were the best management system × cultivar combinations for grain yield. The increased yields for these management system × cultivar combinations were likely due to the cultivars\u27 greater host plant resistance to several bean diseases and tolerance to low soil fertility. The economic return to labor and management was only profitable for the CFS ($40 ha-1), and no differences were observed between cultivars. Additionally, both rainy seasons resulted in a net loss. On the Liddugavu soil, mean grain yield was greater in the HIS (1275 kg ha-1) than in the IFS (818 kg ha-1) and the CFS (593 kg ha-1). Across management systems, disease resistant NABE 14 had greater grain yield (1212 kg ha-1) than NABE 15 (668 kg ha-1), K132 (803 kg ha-1), and NABE 4 (899 kg ha-1). The HIS with NABE 14 had the greatest grain yield (1772 kg ha-1). The increase in yield for NABE 14 was likely due to its greater host plant resistance to several bean diseases including angular leaf spot, bean common mosaic virus, and root rots. The economic return to labor and management resulted in many net losses in the 2015A season, except when planting NABE 14. Over both seasons, the greatest management system × cultivar combination was the HIS with NABE 14 ($559 ha-1). All inputs and seed of bean cultivars used were obtained locally, except the rhizobia, suggesting that increased yields are obtainable by farmers under both soils, especially when utilizing NABE 14 under improved management practices with increased inputs. However, increased profits are only obtainable under the Liddugavu. The greater level of infertility and need for higher rates of nutrients for enhanced bean production on Limyufumyufu resulted in poor yields and poor economic returns to labor and management. The need for inputs was too great for Limyufumyufu and the value of bean was too low to recover the investment for all improved management system combinations

Biogeographical Evidence for the Grass (Poaceae) Species of Pleistocene Beringian Lowlands

Late Pleistocene Beringia had herb-dominated vegetation with abundant grasses (Poaceae), and it was inhabited by an impressive assemblage of large grazing mammals. This paper reconstructs the list of most probable late Pleistocene Beringian lowland grass species from biogeographical evidence. Late Pleistocene eolian sediments and buried soils indicate that large areas of the Beringian lowlands had nutrient-rich, silty soils that occurred over ice-rich permafrost but were generally not waterlogged. A list of likely grasses was compiled from all species that have been recorded on similar fine-grained, mesic-to-dry lowland soils (i.e., presumed refugia) and are distributed at least sporadically across the whole region today. Grasses from 13 genera met these criteria, including most of the taxa that have been identified as late Pleistocene fossils from the study area. Most of these grasses are high-latitude species of genera that are also common in temperate latitudes (e.g., Elymus, Festuca, and Poa). This diverse group of plants has a wide range of adaptations today, suggesting that grasses would have been available to occupy a variety of habitats through Pleistocene climatic fluctuations. Among these grasses are a number of highly productive forage species.La végétation de la Béringie du Pléistocène supérieur était dominée par des herbes abondantes (Poaceae). De plus, elle était habitée par un assemblage impressionnant de gros mammifères broutards. Dans cet article, nous dressons la liste des espèces végétales des basses-terres les plus probables de la Béringie du Pléistocène supérieur à partir d’observations biogéographiques. Les sédiments éoliens du Pléistocène supérieur et les sols enfouis laissent supposer que de vastes régions des basses-terres de la Béringie avaient des sols limoneux riches en nutriments situés sur du pergélisol riche en glace, sans être généralement gorgés d’eau. La liste des herbes susceptibles de s’être retrouvées à l’époque a été compilée à partir de toutes les espèces qui ont été enregistrées sur des sols fins similaires de basses-terres allant de mésoïques à secs (i.e., refuges naturels présumés) et qui sont réparties, de manière tout au moins sporadique, dans toute la région aujourd’hui. Les herbes de 13 genres ont satisfait ces critères, ce qui comprend la plupart des taxons qui ont été identifiés à titre de fossiles du Pléistocène supérieur dans la région visée par l’étude. La plupart de ces herbes sont des espèces de genres se retrouvant en haute altitude qui sont également en latitudes tempérées (comme Elymus, Festuca et Poa). De nos jours, ce groupe de végétaux divers a subi de nombreuses adaptations, ce qui laisse supposer que les herbes auraient occupé une variété d’habitats pendant les fluctuations climatiques du Pléistocène. Parmi ces herbes, notons un certain nombre d’espèces fourragères hautement productives

Monitoring Restoration Impacts to Endemic Plant Communities in Soil Inclusions of Arid Environments

Slickspots are soil inclusions with unique loamy soils that provide habitats for many endemic plants worldwide, including those within sagebrush steppe. Sagebrush-dominated communities are declining and require restoration, but restoration techniques commonly used may impact negatively some intermixed communities found on soil inclusions including those on slickspot soils. Slickspot soils have unique physical and chemical properties that create saline environments with limited plant cover that may include an endangered plant. This study was conducted to yearly variations in slickspot soil areas on sites treated with the herbicide glyphosate and/or seeded with a minimum-till drill relative to control areas. During spring 2004, 2005 and 2006, aerial photography and ground measurements of slickspot areas were taken. Images taken in spring, when vegetation is live and green, can be used to define and measure slickspot soils. Differences among treatments and years of surface area of slickspots were less than 1 m2 per subplot, out of a possible 780 m2 per subplot, and were not statistically significant. This implies that there is no effect of minimum-till drill and/or glyphosate on slickspot soil extent and that slickspots are fairly stable over time. Aerial photography provides faster and comparable results to traditional ground-based monitoring, while providing managers with a reliable means of tracking these ecosystems across a landscape. © 2013 Friends Science PublishersKeywords: Seed drill, Aerial photography, Slickspot extent, Lepidium papilliferum, Glyphosate, Remote sensin

LATE HOLOCENE ACTIVATION HISTORY OF THE STANTON DUNES, NORTHEASTERN NEBRASKA

The Nebraska Sandhills have been an important resource for better understanding dune activation and the nature of prehistoric Great Plains drought events. However, until recently, few studies have focused on documenting the activation histories of smaller dune fields found along the Great Plains\u27 eastern margin. This study focuses on the Stanton dune field, which lies about 145 km east of the Nebraska Sandhills on an alluvial terrace of the Elkhorn River in northeastern Nebraska. Sediments in the Stanton Dunes were dated with optically stimulated luminescence (OSL) to determine when these dunes were active. The ages indicate three activation periods that cluster into the following time periods: ~5,800-3,800, 960-630, and 510-410 years ago. The ages that fall into our two older clusters closely agree with dune activation records from the Nebraska Sandhills and other major central Great Plains dune fields, suggesting that these large-scale droughts also impacted eastern Nebraska. However, our youngest cluster of ages occurs at a time when the Nebraska Sandhills were thought to be largely inactive, suggesting that the Stanton Dunes may have been activated by a locally important drought event that had a more limited impact on dunes found to the west