923 research outputs found
The Utility of a Theoretical Framework of a Culture of Leadership
The purpose of this study is to determine the utility of a Culture of Leadership Framework for both evaluating and contributing to the formation of a dynamic school culture that infuses leadership up, down, and throughout the membership of the school learning community with students as a central figure. The Culture of Leadership Framework emerged from an extensive review of the literature and includes four distinct dimensions (indicators) that become critical to analyzing the data: Leadership Orientation, Leveraging Leadership, Leadership for Learning, and Leadership Growth. The researcher used a general interpretive process of close reading to develop themes from extant feedback and survey data from a ten-year period and an online narrative response from participants at the end of the ten-year period. Using a constant comparative analysis of the themes through the lens of the Culture of Leadership and established look-for success criteria from the four dimensions, the researcher organized the findings from the data across the ten-year timeline. The data showed positive participant language and action changes over time with regard to the leadership principles aligned with the Culture of Leadership Framework. The participants also acknowledged and celebrated student involvement, engagement, and actions related to their exposure to their leadership learning and opportunity. Having established the utility of the Culture of Leadership Framework, the researcher concludes with a practical discussion and an application workshop for a building principal to use to intentionally and purposefully implement a Culture of Leadership Theory of Action
Alien Registration- Wortman, Ethel E. (Easton, Aroostook County)
https://digitalmaine.com/alien_docs/26546/thumbnail.jp
Benchmarking the Agronomic Performance of Biodegradable Mulches against Polyethylene Mulch Film: A MetaâAnalysis
Growers are interested in biodegradable alternatives to petroleumâbased polyethylene mulch film (PEM). However, many growers cite limited knowledge about biodegradable mulch films (BDMs) as a significant barrier to adoption. Agronomic field tests of BDMs are often limited temporally or spatially, and the variability of performance results relative to PEM may be contributing to this perceived knowledge gap. Our objective was to use data available in the scientific literature to provide the first quantitative performance benchmark of BDMs against PEM. We extracted data from 66 articles for metaâanalysis. Response ratios were calculated for comparison of BDMs relative to black PEM, and differences among categorical groups were determined using 95% bootstrap confidence intervals. Overall, BDMs reduced soil temperature by 4.5% ± 0.8% (± one standard error) compared to PEM, and temperatures were coolest beneath paperâ based BDM. Starchâpolyester BDM was less effective than PEM for weed control, but paperâbased BDM reduced weed density and biomass by 85.7% ± 9.2%. Paperâbased BDMs were particularly useful for controlling Cyperus spp. weeds. Despite differences in soil temperature and weed suppression, crop yields were not different between BDMs and PEM. Future research should focus on reducing costs, adding functional value, and increasing the biodegradability of BDMs
Method and apparatus for determining time, direction, and composition of impacting space particles
A space particle collector for recording the time specific particles are captured, and its direction at the time of capture, utilizes an array of targets, each comprised of an MOS capacitor on a chip charged from an external source and discharged upon impact by a particle through a tab on the chip that serves as a fuse. Any impacting particle creates a crater, but only the first will cause a discharge of the capacitor. A substantial part of the metal film around the first crater is burned off by the discharge current. The time of the impulse which burns the tab, and the identification of the target, is recorded together with data from flight instruments. The metal film is partitioned into pie sections to provide a plurality of targets on each of an array of silicon wafers, thus increasing the total number of identified particles that can be collected. It is thus certain which particles were captured at what specific times
Comparison of Organic and Integrated Nutrient Management Strategies for Reducing Soil N\u3csub\u3e2\u3c/sub\u3eO Emissions
To prevent nutrient limitations to crop growth, nitrogen is often applied in agricultural systems in the form of organic inputs (e.g., crop residues, manure, compost, etc.) or inorganic fertilizer. Inorganic nitrogen fertilizer has large environmental and economic costs, particularly for low-input smallholder farming systems. The concept of combining organic, inorganic, and biological nutrient sources through Integrated Nutrient Management (INM) is increasingly promoted as a means of improving nutrient use efficiency by matching soil nutrient availability with crop demand. While the majority of previous research on INM has focused on soil quality and yield, potential climate change impacts have rarely been assessed. In particular, it remains unclear whether INM increases or decreases soil nitrous oxide (N2O) emissions compared to organic nitrogen inputs, which may represent an overlooked environmental tradeoff. The objectives of this review were to (i) summarize the mechanisms influencing N2O emissions in response to organic and inorganic nitrogen (N) fertilizer sources, (ii) synthesize findings from the limited number of field experiments that have directly compared N2O emissions for organic N inputs vs. INM treatments, (iii) develop a hypothesis for conditions under which INM reduces N2O emissions and (iv) identify key knowledge gaps to address in future research. In general, INM treatments having low carbon to nitrogen ratio C:N (2O emissions
Effects of Rootstock and Location on Open Field âBHN 589â and âNebraska Weddingâ Grafted Tomato Yield
Grafted tomato (Solanum lycopersicum) production is popular, particularly in high tunnels, because grafted plants can mitigate soilborne disease incidence in highly infested soils and increase water and nutrient use efficiency and crop yield and quality. However, these potential benefits are not as well documented in open field production systems with less disease pressure. The objective of this study was to quantify the effect of tomato grafting on fruit yield, number, and size across 2 years (2018 and 2019) and three diverse open-field production environments in Nebraska (Lincoln, North Platte, and Dwight). At each location, a scion from one of two determinant fresh market tomatoes, âNebraska Weddingâ (heirloom) or âBHN 589â (commercial hybrid), were grafted onto one of two rootstocks, âEstaminoâ and âMaxifort,â and the nongrafted scion cultivars were controls. In year 2, a fertilizer treatment was introduced (0 and 50 kg·ha-1 N). Ripe tomatoes were harvested weekly, sorted as marketable or cull, counted, and weighed fresh. No marketable or total yield benefits of grafting were observed in 2018 for any scion by rootstock combination across locations. Marketable yield of grafted plants was reduced by 32% in Lincoln. However, grafted âNebraska Weddingâ plants (regardless of rootstock) in North Platte (with coarse-textured, lower organic matter soil) increased fruit number (but not yield) by 50% to 63%. In 2019, grafting âBHN 589â to âMaxifortâ increased total tomato yield by 24% across all locations. The heirloom variety Nebraska Wedding did not benefit from grafting in 2019. âEstaminoâ rootstock did not increase tomato yield, number, or size for either scion variety in either year. Nitrogen fertilizer increased yield as expected in 2019, but grafted plants did not perform better than nongrafted under reduced nitrogen fertility. Results from this study suggest that grafting is not consistently beneficial to âBHN 589â and âNebraska Weddingâ in open field production systems in Nebraska, particularly if there are no known soilborne disease issues
Post-termination Effects of Cover Crop Monocultures and Mixtures on Soil Inorganic Nitrogen and Microbial Communities on Two Organic Farms in Illinois
Cover crops can continue to affect agricultural systems even after they have been terminated by influencing nitrogen dynamics and by altering soil microbial communities. These post-termination effects can influence soil fertility, weed pressure, and the dynamics of potential plant pathogens in the narrow window of time between cover crop termination and cash crop emergence. We evaluated the post-termination effects of 12 different spring-sown cover crop mixtures and monocultures on soil nitrogen and microbial communities on two different organic farms in Central Illinois (on Lawson silt loam soil) and Northern Illinois (on Virgil silt loam soil). In comparison to control plots with no cover crops, all cover crop treatments significantly reduced soil nitrate levels but increased the potentially mineralizable nitrogen pool following termination. Nitrate levels of cover crop plots approached those of controls after 2 and 4 weeks, respectively, but potentially mineralizable nitrogen levels in cover plots remained elevated for at least 4 weeks following termination. Monocultures of Brassica cover crops showed the greatest decrease in soil nitrate, while Brassicas and unplanted control plots containing high biomass of weeds showed the greatest increase in potentially mineralizable nitrogen in comparison to plant-free control plots. In contrast to their effect on soil nitrogen, cover crops had very limited impact on the composition of soil microbial communities. Overall microbial community composition varied across sites and years, and only soil fungi significantly responded to cover cropping treatments. Nevertheless, we found that some highly correlated groups of soil microbes showed significant responses to soil nitrate and to high plant biomass. Key members of these correlated groups included ammonia-oxidizing organisms and saprotrophic fungi. Our results suggest that cover crops may reduce the potential for springtime nitrogen leaching losses by retaining nitrogen in the soil organic pool, and they may also have impacts on the soil microbial community that are particularly relevant for nitrogen cycling and decomposition of plant residues
Knowledge of Pollinator Conservation and Associated Plant Recommendations in the Horticultural Retail Industry
Pollinating insects are integral to the health of all terrestrial ecosystems and agriculture worldwide. Urbanization can greatly reduce nutritional resources and habitat for pollinators. However, these losses can be mitigated through targeted landscape practices, such as planting nectar- and pollen-rich plants and managing pollinator habitat in urban areas, especially home landscapes. As homeowners attempt to conserve pollinators through horticultural practices, they often seek the advice and guidance of horticulture retail employees. The knowledge horticulture employees have about pollinators and the recommendations they provide to customers is largely unknown. A nationwide survey was developed and distributed with the objectives to 1) assess employee knowledge about pollinators and pollination biology, 2) discover what plant and management recommendations employees were giving customers pertaining to pollinator conservation, and 3) determine where to focus possible education and outreach, as well as which topics to focus educational programs on. Our findings suggest, among our respondents, that overall knowledge was adequate, with a mean score (±SD) being 8.37 (±3.23) of a possible range of 0â14 points. Uncertified and part-time employees were identified as having significantly lower scores. The subject of plant selection was found to have the largest gap in knowledge, with a mean score of 1.82 (±0.62) of a possible three points. We identified several opportunities for educational outreach, aimed at improving employee and customer knowledge on this important subject
Air-propelled Abrasive Grit can Damage the Perennial Weed Quackgrass
our field experiments were conducted during 2016 and 2017 to evaluate the efficacy of preemergence herbicides to control glyphosate-resistant common ragweed in corn. Dicamba, dicamba/atrazine, mesotrioneâ+ atrazine, isoxaflutoleâ+âatrazine, saflufenacil/dimethenamid-P, and S-metolachlor/mesotrione/bicyclopyrone/atrazine were the most efficacious herbicides, providing 94%â100% control of GR common ragweed and reducing density and biomass 98%â100%
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