79 research outputs found

    Identification of Soil-Water Chemical Parameters for the Prediction and Treatment of Suspended Solids in Surface Water Reservoirs of Coal Mine Lands

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    High concentrations of suspended solids in coal mine sedimentation ponds are a factor in lowering water quality. This study focuses on the influence dissolved solids have on concentration and settling of suspended solids. Water samples from sedimentation ponds in Eastern and Western Kentucky were used to evaluate water composition in such ponds. Spoil samples from surface mine sites in both parts of the state were used to evaluate water composition released from the spoils upon introducing water. The results demonstrate that water quality emanating from coal spoils of Eastern and Western coal mines is dependent on the type of spoil and/or geologic strata represented. Water composition of randomly selected sedimentation ponds revealed that the relationship between electrical conductance (EC) in mmhos cm-1 and ionic strength (I) of water is I = 0.012 [EC]. Furthermore, it was determined that there is a linear relationship between the repulsive index, RI = [(0.012)(EC)]-1/2 (based somewhat loosely on double-layer theory), and suspended solids. Kinetic data on settling of suspended solids has shown that upon increasing the ionic strength of the water (consequently decreasing RI), the rate of settling increased dramatically. The critical RI at which complete removal of all suspended solids, estimated by graphic extrapolation, is shown to be dependent on the percent base saturation. The data also demonstrate that the critical RI (RI at maximum flocculation) varies depending on the spoils mineralogical and chemical composition. The overall study shows that decreases in suspended solids in coal mine sedimentation ponds can be brought about by relatively small increases in ionic strength. Several approaches as to how one might increase water ionic strength in sediment ponds are discussed

    Identification of Soil-Water Chemical Parameters for the Prediction and Treatment of Suspended Solids in Surface Water Reservoirs of Coal Mine Lands

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    High concentrations of suspended solids in coal mine sedimentation ponds are a factor in lowering water quality. Colloidal particle settling simulations were carried out in the laboratory to test the influence pH and dissolved solids have on concentration and settling rates of suspended solids. The results of the study reveal that the pH range of colloidal coflocculation for the samples tested is between 3.5 and 4.5. Furthermore, liming simulation of acidic sediments, as expected increased colloid dispersion. This increase was dependent on the magnitude of the sodium adsorption ratio (SAR). The greater SAR systems maintained a greater concentration of colloidal suspended particles. However, for the same SAR value when the ionic strength was increased from 4 meq L-1 to 8 meq L-1, sedimentation rate of colloidal particles decreased. The data also show evidence that for the same SAR values when substituting magnesium for calcium, the rate of particle settling increased for one sample but decreased for another. This unexpected behavior is under further investigation

    Grain Sorghum and Soybean Variety Tests on Reconstructed Prime Land - 1985

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    Prime farmland disturbed by surface mining must by law be returned to a productivity level equal to that before mining. The coal operator has several test crops that can be selected to determine whether these production standards have been met before final bond release will be made. Grain sorghum and soybeans are two of the crops that may be used. The purposes of this research are (1) to determine the crop yield potential of restored prime farmland from surface mined areas, (2) to determine varietal adaptation on restored prime farmland as compared to non-mined prime farmland, and (3) to provide crop yield data to Kentucky farmers on grain sorghum and soybeans from restored prime farmland

    Genetic and maternal effects on tail spine and body length in the invasive spiny water flea (Bythotrephes longimanus)

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    Interest in the evolution of invasive species has grown in recent years, yet few studies have investigated sources of variation in invasive species traits experiencing natural selection. The spiny water flea, Bythotrephes longimanus, is an invasive zooplankton in the Great Lakes that exhibits seasonal changes in tail spine and body length consistent with natural selection. Evolution of Bythotrephes traits, however, depends on the presence and magnitude of quantitative genetic variation, which could change within or across years. Clonal analysis of wild-captured Bythotrephes indicated that variance components for distal spine length were variable among but not within years. Spine length was always heritable but was not always influenced by maternal effects. In contrast, variance components for body length varied both within and among years, but likewise body length was always heritable and not always influenced by maternal effects. Results indicate that important Bythotrephes traits have heritable variation comparable to native species and other invasive species that would enable an evolutionary response to natural selection. This evolutionary capacity could contribute to the widespread success and dramatic effects of Bythotrephes invasion in systems with diverse biotic and abiotic conditions

    Zooplankton spine induces aversion in small fish predators

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    The spined cladoceran Bythotrephes cederstroemi is protected from small fish predators due to the difficulty small fish have in ingesting the spine. Juvenile yellow perch (Perca flavescens) 50–60 mm in length were offered Bythotrephes with alternative prey available in two experiments. First, perch were observed as they gained experience with Bythotrephes and developed aversion to the zooplankter. Perch initially attacked and captured Bythotrephes . However, they struggled to ingest the spined zooplankter, rejected and recaptured it many times, and finally ceased to attack it. Second, perch were offered Bythotrephes with varying portions of the spine removed to clarify the spine's role in inducing such behaviors. Perch showed greater preference to attack nospine and half-spine Bythotrephes , and were less likely to reject and more likely to ingest Bythotrephes with the spine removed. For small or young fish that forage on zooplankton in lakes where Bythotrephes is present, aversion is an efficient response to the conspicuous but unpalatable spined cladoceran. However, aversion allows Bythotrephes , also a predator on zooplankton, to more effectively compete with young fish without an increase in predation risk.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47794/1/442_2004_Article_BF00317591.pd
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