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11.
Jordan L. Youngmann Randy W. Deyoung Stephen Demarais Bronson K. Strickland Gabe Jenkins 《The Journal of wildlife management》2020,84(3):515-523
Translocations are a common management practice to restore or augment populations. Understanding the genetic consequences of translocation efforts is important for the long-term health of restored populations. The restoration of elk (Cervus canadensis) to Kentucky, USA, included source stocks from 6 western states, which were released at 8 sites in southeastern Kentucky during 1997–2002. We assessed genetic diversity in restored herds and compared genetic similarity to source stocks based on 15 microsatellite DNA loci. Genetic variation in the restored populations was comparable to source stocks ( allelic richness = 3.52 and 3.50; expected heterozygosity = 0.665 and 0.661 for restored and source, respectively). Genetic differentiation among all source and restored populations ranged from 0.000 to 0.065 for pairwise FST and 0.034 to 0.161 for pairwise Nei's DA. Pairwise genetic differentiation and Bayesian clustering revealed that stocks from Utah and North Dakota, USA, contributed most to restored populations. Other western stocks appeared less successful and were not detected with our data, though our sampling was not exhaustive. We also inferred natural movements of elk among release sites by the presence of multiple genetic stocks. The success of the elk restoration effort in Kentucky may be due, in part, to the large number of elk (n = 1,548), repeated releases, and use of diverse source stocks. Future restoration efforts for elk in the eastern United States should consider the use of multiple stock sources and a large number of individuals. In addition, preservation of genetic samples of founder stock will enable detailed monitoring in the future. © 2020 The Authors. The Journal of Wildlife Management published by Wiley Periodicals, Inc. on behalf of The Wildlife Society. 相似文献
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Chaney Lake State Nature Preserve is a 68 ha ephemeral karst lake in southern Warren County, Kentucky (USA). Chaney typically fills with water in the winter as groundwater levels rise and then slowly dries via evaporation and drainage back into the subsurface over the summer months. The lake contains several habitat types, identifiable by the dominant plant communities, which may have different physiochemical characteristics. Since these differences may result in an increase in habitat heterogeneity and niches available for colonization by resident zooplankton, a suite of physiochemical and nutrient parameters was monitored in these habitats from January 1997–August 1998. Zooplankton densities and community structure were assessed from January 1997 through May 1998. There were few significant differences among the habitats but there were significantly higher concentrations of NOx and higher specific conductivities associated with some of the groundwater inlet areas in the lake. Zooplankton were abundant, but there were no differences in zooplankton densities among the areas sampled. These results suggest that the physiochemical properties in the lake are heavily influenced by the groundwater inputs and that land use patterns around Chaney Lake may be having an impact on the preserve. 相似文献
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Diatom and water chemistry data from 35 wetland sites in western Kentucky were used to assess diatoms as indicators of ecological conditions in wetlands. The wetlands were affected by different degrees of acid mine drainage and agriculture. Canonical correspondence analysis indicated that the distribution of diatoms was highly correlated with conductivity and total phosphorus (TP), two variables commonly associated with acidic mine drainage and agriculture, respectively. Diatom-based inference models were developed for use as quantitative indicators of two important environmental variables in wetlands: conductivity and TP. Diatom-inferred conductivity and TP values were highly correlated with measured values. Cross-validation with jackknifing procedures suggested that high apparent r2 between inferred and measured conductivity was overly optimistic and should be treated with caution. Jackknifing-derived TP inference models performed poorly in predicting TP toward the ends of low and high TP concentrations. In general, the conductivity inference models based on plankton had better predictability than those based on epiphyton. Epiphyton-based inference models can predict TP better than plankton. Therefore, diatoms in planktonic and epiphytic assemblages could provide complementary information on ecological conditions. Our data suggest that diatoms can reflect major regional environmental gradients and therefore can be used as indicators of the ecological conditions in wetlands. Quantitative inference models with known predictive power can aid the development of realistic and ecologically sound biotic indices for this region. 相似文献
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R. B. Malek 《Journal of nematology》1980,12(1):1-6
The effects of temperature on population development of 11 species of stunt nematodes in the subfamily Tylenchorhynchinae were compared on red clover or Kentucky bluegrass in constant-temperature tanks at 5-degree intervals from 10 to 35 C. The optimum temperature for population increase on red clover in 90 days was 30 C for Tylenchorhynchus agri, T. nudus, T. martini, and T. clarus, 25 C for T. sylvaticus and T. dubius, and 20 C for T. canalis, Merlinius brevidens, and Quinisulcius capitatus. The optimum was 30 C for T. robustoides and 25 C for T. maximus on Kentucky bluegrass. The temperature range for population increase was 20-35 C for T. agri, T. nudus, T. martini, and T. clarus, 20-30 C for T. sylvaticus and T. robustoides, 15-25 C for T. maximus, 10-25 C for T. dubius, and 10-20 C for M. brevidens and Q. capitatus. T. canalis increased only at 20 C. All species were recovered in numbers near their inoculum level at 10 C. There was no survival of T. sylvaticus, T. dubius, T. canalis, T. robustoides, T. maximus, M. brevidens, and Q. capitatus at 35 C, or of the last three of these species at 30 C. Temperature had no effect on sex ratio in final populations. Population increase was greatest in T. martini and least in T. canalis. 相似文献
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The association between various parameters of acute and chronic smoking status and plasma levels of three proteins, C9, C1-inhibitor (C1-INH) and alpha 1-protease inhibitor (alpha 1-PI) were determined for 49 male cigarette smokers and 49 age-matched nonsmokers (mean age = 32.2 years). The mean number of cigarettes smoked was 28.7 per day while the cumulative consumption was only 18.1 pack-years. Plasma levels of all three proteins were significantly higher in the smokers than nonsmokers. Plasma C9 and alpha 1-PI concentrations correlated with cumulative cigarette consumption and plasma nicotine concentrations. While C1-INH concentration did not correlate with either cumulative cigarette consumption or plasma nicotine concentration, it correlated significantly with serum thiocyanate concentration. No consistent correlation was found between plasma concentration of these proteins and parameters of pulmonary function. 相似文献
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Seasonality in river phytoplankton: multivariate analyses of data from the Ohio River and six Kentucky tributaries 总被引:1,自引:3,他引:1
Two years of physical/chemical and algal abundance data obtained from national Stream-Quality Accounting Network records of 10 river sites in Kentucky USA (4 Ohio River sites and 6 Ohio River tributaries) were analyzed to determine how seasonal changes in river phytoplankton related to changes in physical and chemical parameters. Phytoplankton assemblages differed among rivers as a function of drainage basin characteristics, but exhibited common seasonal changes related to temporal variation in the physical/chemical environment. Distinct shifts in algal dominance were identified between spring (March, April), late summer (July, August, September), and transitional (May, June, November) periods in the 10 systems. Nine common algal genera were found to differ in their response to changes in physical or chemical parameters. Abundances of Anacystis, Oscillatoria, Scenedesmus, and Melosira were strongly positively correlated with temperature while Chlamydomonas and Navicula abundances were inversely related to temperature. Other physical/chemical factors that were significantly positively ( + ) or negatively ( - ) correlated with algal abundances included discharge and alkalinity (Oscillatoria, +), pH CChlamydomonas and Cyclotella, (both + ), turbidity (Anacystis, \s- ; Navicula + ), silica (Cyclotella, - ), and ammonium/organic N (Anacystis, -). Genera within the same algal division exhibited different seasonal patterns and responded to different physical/chemical parameters. 相似文献