196,346 research outputs found
Landslide dambreak flooding in the Callery River, Westland
No full textIn 1930 dambreak flooding, which initiated in the Callery River, threatened Franz Josef Glacier. This town is centred in a high-risk natural hazard zone, which includes threat from earthquakes, catastrophic landslides, and rainfall flooding from the Waiho River. The threat from landslide dambreak flooding in the Callery River has prompted this investigation.
On a geological time scale, the formation and failure of landslide dams in New Zealand is common, and usually occurs in geological settings similar to those of the Callery River Gorge. Aerial inspection of this gorge confirmed that landslide activity in this catchment is extremely high.
Seven possible landslide dam sites were identified in the Callery River Gorge. Physical modelling was carried out to predict the shape of landslide deposits on the valley floor. Four dambreak models were used to simulate the overtopping failure of these dams. Three of the models relied heavily on embankment dambreak technology, as technology for simulating landslide dambreaks is at an immature stage.
If a landslide dam break occurred in the Callery River, resulting discharges could be between 2,000 m³/s for smaller dams, and 17,000 m³/s for larger dams. For smaller dams, the flood duration was usually 4 hours, and for larger dams, 2 hours. Attenuation of the dambreak flooding was negligible. Floodwater velocities were between 14 and 19 m/s.
A landslide dambreak could immediately transport between 100,000 to 2,000,000 m³ of material into the Waiho River. However, a significant proportion of most landslide dams did not erode immediately, and could eventually be transported to the Waiho River in future rainfall flood events. Immediate deposition of sediment on the Waiho River bed, accumulation of vegetation debris on bridge piers, and residual long-term sediment delivery will greatly reduce the conveyance of the channel under State Highway 6. Long-term residual sediment delivery to the Waiho River from a small landslide dambreak could be more adverse (in reducing conveyance at State Highway 6) than the actual dambreak flood.
Structural methods for protecting assets and people from dambreak flooding at
Franz Josef would be too expensive for the community. Resources may be better invested in non-structural options for mitigating the hazard. Possible mitigation methods mainly comprised physically altering the landslide dam and pre-warning for evacuation-
1. As the Callery River Gorge is not accessible by ground, access by air and use of explosives may be the only way to physically alter the dam.
2. Immediate warning of a landslide dam break may allow for the evacuation of residents. Robust telemetry installed at the Callery Footbridge, and inspection of the Callery Catchment during heavy rainfall or after a large earthquake may provide this warning.
Assuming a landslide dam is identified immediately, warning time for evacuation during a rainfall triggered landslide dam could be between 1 to 10 hours. Pre-warning for earthquake events could be between 2 days to 1 month, or between 2 hours to 1 day if a large rainfall event occurred after the earthquake. Detection of a landslide dam in heavy rainfall and/or night conditions may not be possible. In a worst case scenario, up to 30 lives could be lost.
The threat from landslide dambreak flooding to Franz Josef is very real. This threat has at least a 1% chance of occurring annually, and is outside accepted risk limits established by the New Zealand Society of Large Dams (NZSOLD). Evacuation and mitigation procedures need to be put in place immediately
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Callery Chemical Company Report 1024-TR-213
No full textTechnical report abstract: Sodium hydride and triethylborane react to form sodium triethylhydroborate, NaBH(C2H5)3. This compound, a liquid at rooom temperature, was found to be soluble in hexane and mineral oil. A study was made of the thermal decomposition of sodium triethylhydroborate and its behavior toward boron trifluoride, boron trichloride, methyl borate, carbon dioxide, silane, and ethylene. Sodium triisopropoxyhydroborate, NaBH(OC3H7)3, was prepared and also found to be soluble in hexane and mineral oil. The reactions of this compound with methyl borate, triethylborane, silicon tetrachloride, and boron trichloride were investigated
Estimating Invading Callery Pear (Pyrus calleryana) Age and Flowering Probability in an Indiana Managed Prairie
No full textCallery pear (Pyrus calleryana Decne.) is an invasive species in North America originating from Asia. As an ornamental tree, Callery pear has been widely planted throughout much of the United States and has subsequently spread into natural areas. Callery pear individuals that had naturally colonized a managed prairie in Indiana were collected. Tree height and root collar diameter were measured and the presence of flower buds was identified. After harvesting the trees, age was measured as ring counts. Height, root collar diameter, and age were all significantly greater for flowering individuals compared to nonflowering trees. Root collar diameter was the only independent variable that resulted in a significant linear model for predicting tree age. Additionally, root collar diameter effectively predicted the likelihood of flowering in Callery pear, with a tree root collar diameter of 45.6 mm predicting a 50% chance of flowering. Age was an ineffective independent variable in predicting flowering potential in Callery pear. Root collar diameter can provide a rapid assessment of invasion age, as well as predicting flowering potential outside of the growing season. Management focus can be on larger individuals
The Effect of Callery Pear (Pyrus calleryana) on Soil Macrofauna (Diplopoda and Oligochaeta)
No full textCallery pear (Pyrus calleryana) is a relatively recent invader of North America. Its ecological effects are still being explored, including those affecting soil macrofauna such as millipedes (Diplopoda) and earthworms (Clitellata: Oligochaeta). These animals play important roles in many soil processes so understanding how they respond to invasive species is vital to soil health. A previous study exploring potential herbicide control was completed in 2019, however as of 2022 there are still treatment zones with little to no Callery pear alongside fully invaded plots, providing an optimal habitat mosaic for comparison. This allowed us to pursue two research goals: To determine the medium-term (3–4 years) effects of chemical control and to determine how soil macrofauna biodiversity is affected by the local plant community in the presence of invasive Callery pear. Soil fauna were sampled using four methods for thorough investigation. 1) Leaf litter was processed in Berlese funnels to draw out small millipedes. 2) Large millipedes were collected on sight by hand. 3) Earthworms were collected by digging soil monoliths and sorting through the soil by hand. 4) Additional earthworm collections were done via the octet method, using an electroshock machine to drive fauna out of the ground. Surveying the pla nt communities and collecting soil for texture, pH, and C:N ratios also helped achieve the goals of this study. We found that Shannon plant diversity indices were lower in the Callery pear plots but statistically similar between the herbicide and reference plots, suggesting the effectiveness of chemical control. Additionally, millipede diversity (Shannon index) was positively correlated with basal area of live Callery pear but was not statistically different between treatments. Nonnative earthworm abundance had no correlation with Callery pear. These findings will help land managers make informed decisions when creating management plans for invasive pear
THE EFFECT OF CALLERY PEAR (PYRUS CALLERYANA) ON SOIL MACROFAUNA (DIPLOPODA AND OLIGOCHAETA)**
No full textCallery pear (Pyrus calleryana) is a relatively recent invader of North America. Its ecological effects are still being explored, including those affecting soil macrofauna such as millipedes (Diplopoda) and earthworms (Clitellata: Oligochaeta). These animals play important roles in many soil processes so understanding how they respond to invasive species is vital to soil health. The goals of this study are two-fold: To determine the medium-term (3–4 years) effects of chemical control and to determine how soil macrofauna biodiversity is affected by the local plant community in the presence of invasive Callery pear. Soil fauna will be sampled using four methods for thorough investigation. 1) Leaf litter will be processed in Berlese funnels to draw out small millipedes. 2) Large millipedes will be collected on sight by hand. 3) Earthworms will be collected by digging soil monoliths and sorting through the soil by hand. 4) Additional earthworm collections will be done via the octet method, using an electroshock machine to drive fauna out of the ground. Surveying the plant communities and collecting soil for texture, pH, and C:N ratios will also help achieve the goals of this study. A previous study exploring potential herbicide control was completed in 2019, however as of 2022 there are still treatment zones with little to no Callery pear alongside fully invaded plots, providing an optimal habitat mosaic for comparison
Letter from M. Eaton to Hagan
No full textHolograph letter from M. Eaton, St. Patrick’s College, Maynooth (County Kildare), to (Hagan), asking to obtain the papal blessing for Gertrude Mary Flynn and Patrick [Callery], County Roscommon. Comments on Dr. Downey's sad death; the Bishop of Ardagh is also said to be dying. Recommending Dr. John Magennis, Dublin, about to visit Rome
Dr. Duane M. Jackson, Morehouse College, July 2011
No full textThis video is a conversation with Dr. Duane M. Jackson. Dr. Jackson talks about his paper, "Recall and the Serial Position Effect: The Role of Primacy and Recency on Accounting Students' Performance." Jackie Daniel, AUC Woodruff Library, is the interviewer
"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States" By M. Carey.
No full text"Reflections on the subject of Emigration from Europe with a view to Settlement in the United States: containing bried sketches of the moral and political character of those states.
By M. Carey, member of the American philosophical, and of the American Antiquarian Society, and author of The Olive Branch, Cindiciae Hibernicae, essays on banking, on political economy, and on internal improvement.
To which are now added the English editor's comments on the subject; together with Important Advice to Emigrants, and Cautions Against Impositions Practiced in the Outports
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Dr. Glendon Swarthout
No full textHosted by Roger M. Busfield, MSU Assistant Professor of Speech and Theater, Meet the Author is designed to introduce a general audience to a contemporary author and their work through in-depth interviews. This episode features a conversation between Dr. Glendon Swarthout, prolific author and English professor at MSU, and assistant professors Sam S. Baskett and Theodore B. Strandness
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