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Full-Text Articles in Physical Sciences and Mathematics
Continued Ddt Persistence In Mississippi River Delta Streams: A Case Study, Stephen A. Sewell, Luther A. Knight Jr.
Continued Ddt Persistence In Mississippi River Delta Streams: A Case Study, Stephen A. Sewell, Luther A. Knight Jr.
Journal of the Arkansas Academy of Science
Fish samples representative of several trophic levels were taken from the Wolf and Loosahatchie Rivers of western Tennessee during the early 1980s. Results indicate that DDT, with metabolites DDD and DDE, remains common in fish tissues in these areas and approaches the levels recommended as maxima for human consumption by the U.S. Food and Drug Administration. Samples of top carnivores and forage fishes, particularly the gizzard shad, Dorosoma cepedlanum, commonly exceeded 500 ppb DDE. The results are discussed in light of sediment disturbing activities.
Penetrating Ionizing Radiation Levels Observed In The Lower Arkansas And White River Valleys Of Arkansas, C. E. Epperson, S. Meiners, D. Swindle
Penetrating Ionizing Radiation Levels Observed In The Lower Arkansas And White River Valleys Of Arkansas, C. E. Epperson, S. Meiners, D. Swindle
Journal of the Arkansas Academy of Science
Environmental levels of penetrating ionizing radiation were measured in the lower Arkansas and White River valleys of Arkansas. Measurements of environmental gamma and cosmic rays were made using a portable high pressure ionization chamber. The surveyed area encompassed a large coal-fired industrial plant. Observed exposure rates ranged from 5.9 microRoentgens per hour (μR/h) to 13.4 μR/h. The average exposure rate for the region was 8.8 μR/h. This value corresponds to 77 millirem (mrem) or 0.77 milliSieverts (mSv) per year. In comparison, a prior state-wide survey reported an average dose equivalent rate of 78.2 mrem (0.782 mSv) per year in Arkansas.
Survey Of 1985 Periodical Cicada (Homoptera: Magicicada) Emergence Sites In Washington County, Arkansas, With Reference To Ecological Implications, Douglas A. James, Kathy S. Williams, Kimberly G. Smith
Survey Of 1985 Periodical Cicada (Homoptera: Magicicada) Emergence Sites In Washington County, Arkansas, With Reference To Ecological Implications, Douglas A. James, Kathy S. Williams, Kimberly G. Smith
Journal of the Arkansas Academy of Science
Systematic roadside surveys were conducted in June 1985 in Washington County, Arkansas, to locate areas where 13-year periodical cicadas had emerged during May. Although cicadas were found in a variety of upland and bottom land forest habitats, the present cicada distribution reflects the original forest and prairie pattern in the county, even though those boundaries are now largely lost. This suggests a high degree of philopatry whereby emergency areas have remained in the same area for the last 100 years. All present day emergence areas are within the White River drainage, suggesting that it was the main cicada dispersal route …