4,144 research outputs found
The Rainbow Skink, Lampropholis delicata, in Hawaii
The rainbow skink, Lampropholis delicata, arrived in Hawaii
as an accidental import from Australia sometime about 1900, but its true
identity went unknown until recently. Previously, L. delicata in Hawaii had
been identified as Lipinia noctua, Leiolopisma hawaiiensis, and Lygosoma
metallicum (the latter apparently does not occur in Hawaii). Lampropholis
delicata establishes high-altitude records for reptiles in Hawaii at 1130 and
1220 m elevation on the islands of Hawaii and Kauai, respectively. Variations
in body size and numbers of eggs produced in populations on Hawaii, Kauai,
and Oahu suggest that competition for space and food may be lowering reproductive
capacity, and inhibiting growth in the relatively dense populations
on Oahu
Hybrid Hibiscadelphus (Malvaceae) in the Hawaiian Islands
First- and second-generation hybrids of Hibiscadelphus
giffardianus Rock and H. hualalaiensis Rock have been found in Hawaii
Volcanoes National Park, and elsewhere in the Hawaiian Islands. They are
under cultivation from interspecifically cross-fertilized seed which occurred on
parent trees within the park. A history of parent and hybrid species is given,
and floral characteristics are analyzed. Hybrid occurrence and the implications
to natural resource management in trying to preserve the integrity of native
Hawaiian species and ecosystems are discussed
Evaluation of Methods for Diagnosing Contamination in Rural Wells
Three diagnostic procedures were tested to determine their potential usefulness in identifying faulty rural wells: (1) monitoring wells were constructed at three depths near each of three rural wells having a history of nitratenitrogen and/or herbicide contamination, and all wells were sampled daily for four weeks and tested for nitrate-nitrogen, atrazine, alachlor, metolachlor, and chloride; (2) a chloride tracer solution was ponded around each of the water supply wells, and the shallowest monitoring well at each test site, for a period of 8 h during which the wells were continuously pumped and sampled for the tracer; and (3) nitrate-nitrogen and herbicide samples were collected from the water supply wells during the 8-h pumping period to observe contaminant variability during periods of continuous drawdown. Daily sampling revealed little temporal variability in the quality of water from the monitoring wells or the contaminated water supply wells. The monitoring wells, though limited in number, identified significant contaminant stratification within the shallow glacial drift aquifers supplying the water supply wells, and identified one water supply well that was producing water with much poorer quality than the shallow aquifer was capable of producing. The chloride tracer test was successful in distinguishing contaminant entry via preferential flow from that occurring through matrix flow in two of the case study wells, but proved ineffective on a third well where monitoring well data strongly suggested casing leakage. Nitrate-nitrogen and herbicide data showed little variability during the 8-h period of continuous well drawdown
Two Quality Assurance Measures for Pesticide Analysis of Wellwater: Degradation in Storage and GC/ELISA Comparison
At the request of Environmental Protection Agency (EPA) project coordinators, two special quality assurance components were included in a study of herbicides in rural wells in Iowa. Since the study involved daily sampling of 88 rural wells for a period of four to five weeks, it was anticipated that samples would be in refrigerated storage for up to eight weeks during which microbial and chemical activity could lead to analyte loss. The sample degradation study reported here was conducted to insure that water samples containing three herbicides (atrazine, alachlor, and metolachlor) did not undergo excessive losses during storage. Results indicate no reduction in pesticide concentrations in six refrigerated water samples analyzed weekly during an eight-week storage period
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Lithium and carbon isotopic fractionations between the alteration assemblages of Nakhla and Lafayette
Nakhla and Lafayette delta 7Li values for samples and extracts (4.1-14.2�) are consistent with brine evaporation. Relatively 13C-poor siderite in Lafayette suggests more than one carbon source was sampled
Bishop James C. Baker
Bishop Baker was a graduate of Chaddock College, Quincy, Illinois in 1898. IWU incorporated Chaddock alumni into the IWU Alumni Roll following the college\u27s closure. Baker received a Doctor of Divinity from IWU in 1923 and Doctor of Laws in 1928. Brief biographical profiles and pictures are available in The Argus at http://collections.carli.illinois.edu/u?/iwu_argus,17336 and http://collections.carli.illinois.edu/u?/iwu_argus,15966
Subsurface Application of Herbicides
Traditional methods of preplant herbicide application often involve a broadcast spray followed by one or more incorporation passes. Incorporation reduces the amount of crop residue on the soil surface, which can lead to increased soil loss through wind and water erosion. Incorporation also distributes the herbicide more evenly throughout the soil profile, reducing chemical concentrations in the surface mixing zone. Chemicals located within the 1-2 em mixing zone contribute to herbicide losses with surface runoff (Mickelson et al., 1983; Baker et al., 1979). Conservation tillage, as defined by leaving a minimum of 30% of the soil surface covered by crop residue after planting, allows for incorporation of herbicides while still leaving adequate residue on the surface to reduce erosion losses. Although incorporation has been shown to be extremely effective in reducing surface runoff losses of herbicides, it also is the major contributor to reduced residue cover. No-till, the extreme end of conservation tillage, uses no tillage and maximized residue cover for maximum erosion control. Unfortunately, due to surface application of herbicides, no-till often prevents the use of the more volatile and moderately adsorbed herbicides. In some cases, no-till can increase herbicide concentration and losses with runoff water when compared to conventional tillage (Mickelson et al., 1995)
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