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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

EVALUATION OF THE PERFORMANCE OF FLOCCULATION TO ENHANCE SEDIMENT TRAP EFFICIENCY

Scott, Derek 01 January 2015 (has links)
Weathered sandstone materials have seen increased use in reclamation due to the wide-spread adoption of the Forest Reclamation Approach (FRA) in Appalachia. Runoff from these newly FRA reclaimed sites has the potential to adversely impact aquatic environments without fine sediment retention. To reduce the size and capital investment of settling ponds, flocculant utilization was investigated. Preliminary jar tests were conducted using composite weathered mine spoil samples acquired from a surface coal mine in eastern Kentucky. Four flocculants from the Magnafloc family of products were investigated during the initial screening-level testing. Experiments were conducted at three initial sediment concentrations (500 mg/L, 2,500 mg/L and 5,000 mg/L). A nonionic flocculant, Magnafloc 351, performed best, reducing total suspended sediment to below 50 mg/L. Large scale experiments confirmed that Magnafloc 351 was effective in reducing sediment concentrations. Jar tests were expanded to determine age and environmental effects on a Magnafloc 351 solution. Magnafloc 351 performance was slightly reduced after storage in a controlled building environment for 30 days and significantly decreased after 120 days. Magnafloc 351 solution exposed to UV and high heat (111°F) was ineffective after 30 days, while storage at 4°F and 36°F for 30 days did not adversely influence performance.
22

Microbial Bioassay Techniques for Assessing Acid Mine Spoil Amendments for Revegetation

Anderson, Michael A. 01 May 1976 (has links)
The revegetation of sterile acid mine spoils is a costly and lengthy process due to the many factors (pH, toxic materials, low nutrients, poor soil structure, temperature, moisture, length of growing season, etc.) which impede the establishment of stable plant communities . A microbial bioassay t echnique applied to soil systems has been developed to allow a rapid (four weeks) and integrated (with respect to nutrients and toxicants) determination of the best amendments for stabilizing mine spoils by revegetation. Using mine spoil from the Blackbird Mine, Cobalt (near Salmon), Idaho, various comb illations of nitrogen, phosphorus, chelaors, trace elements, potassium, manure and sal t leaching were studied with the bioassay by observing microscopically and by measuring nitrogen fixation and accumulation, dehydrogenase activity, chlorophyll~ accumulation, and other chemical parameters. It was concluded that the limiting factors for microbial (algal) growth were, in order of importance, pH control, soil moisture, and phosphorus. Other treatments failed to show statistically significant better results over the control. The fate of phosphorus in the spoil and its effecton growth response kinetics is also speculatively discussed.
23

Survival and growth of pine seedlings on strip-mined sites

Schoenholtz, Stephen H. 13 March 2010 (has links)
The effects of cultural treatments including ectomycorrhizal inoculation, chemical weed control, and slow-release fertilization on survival, growth, ectomycorrhizal colonization, and foliar nutrient levels of container-grown white (Pinus strobus L.), loblolly (P. taeda L.), and Virginia pine (P. virginiana Mill.) seedlings were studied on a recontoured and a fiat bench strip-mine site in Southwestern Virginia. One-half of the seedlings was inoculated with Pisolithus tinctorius (Pers.) Coker and Couch (Pt). A 21 g Agriform starter tablet was placed in the soil at a depth of 10 cm within 10-15 cm of each seedling in one-half of the plots at planting. Glyphosate was applied to one-half of each plot prior to planting and again later in the growing season. First year survival was not different between sites and was not significantly affected by the cultural treatments. Abundant precipitation and high soil moisture levels throughout the initial growing season may have accounted for the excellent first year survival. The combination of chemical weed control and fertilization significantly increased the growth of all three species. Pt inoculation enhanced seedling growth to some extent but high amounts of natural ectomycorrhizal colonization masked some of the effects of Pt. Levels of foliar nitrogen closely reflected the effects of each treatment on seedling growth, indicating that it was the growth-limiting nutrient for pine seedlings on these strip-mined sites. / Master of Science
24

Hydroseeding pine-grass-legume mixtures for erosion control and reforestation of mine spoils

Preve, Ricardo E. January 1983 (has links)
Growth and mycorhizal colonization of surface-seeded pine (Pinus spp.) as affected by two mine-spoil types (siltstone and sandstone), two fertilizer levels (control and 100 kg/ha each of N, P, and K), and three mycorrhizal inoculation treatments (control, 56 kg/ha pine litter, and 250g/ha Pisolithus tinctorius spores) were evaluated in a greenhouse experiment. The effects of four nurse crops and three fertilizer levels on ground cover, spoil erosion, and establishment of hydroseeded pines on a recontoured strip-mine in southwestern Virginia were also studied. In the greenhouse experiment, germination was highest (12, 55, and 34% for P. strobus, P. virginiana, and P. taeda, respectively) in non-fertilized siltstone, but survival was highest (85, 100, and 95% for the same species) in non-fertilized sandstone. Seedlings grown in fertilized sandstone had significantly higher stern and root biomass than those Mycorrhizal in any other inoculation spoil and treatments sandstone but not in siltstone spoil. In the field experiment, use fertilizer combination. were effective in of a nurse crop significantly increased ground cover over the controls, but the addition of a nurse crop or fertilizer resulted in a decrease in pine establishment of at least 46%. The only nurse crop to obtain the minimum 75% ground cover required by law was a Lolium perenne, Festuca rubra, and Lotus corniculatus mixture which, at 60 kg N/ha, reduced spoil erosion by about 70% over the controls while still allowing the establishment of 6,000 trees/ha. / M.S.
25

Vliv toxicity a ostatních vlastností výsypkových substrátů na růst rostlin / The effect of toxicity and othet parameters of substrate on plant growth in post mining sites.

Zadinová, Radka January 2013 (has links)
Surface mining of coal in the country leaves a lot of damage. This type of mining is characterized by the creation of large external dumps. The dumps often contain substrates with toxic substances or substances which become toxic after reaction with air. These substrates are toxic to plants and edaphon. This work is intended to show what properties of substrates are important for phytotoxicity. The location of research was selected including 3 different kinds of substrates, terrain unevenness and a lagoon in the middle. Coordinate grid has been created on the selected location. At each point a test was conducted with plant Sinapis alba and biomass was extracted from a naturally growing vegetation. Further, at the points substrates were collected and values of pH, conductivity and arsenic were measured. Test with plant Sinapis alba was repeated in the laboratory conditions as well. On site GPS coordinates were measured for the mathematical model created in ArcGIS. Experiment has shown the importance of the type of substrate and the geologic description, and then the association between dejection, value of pH and conductivity. Conductivity and pH levels also correlate with the germination Sinapis alba and biomass of naturally growing vegetation.
26

Faktory ovlivňující šíření dubu letního na výsypce po těžbě uhlí / Factors affecting oak spreading on post mining heaps

Janoušová, Ivana January 2013 (has links)
The study was conducted on spoil heap Podkrušnohorská (50 ř 14'09 S, 12 ř 39'05 V) near Sokolov. Several factors that influence the establishment of oak were studied: the distance from the source of diaspors, type of habitat (succession vs alder reclamation), position of seedling on the wave and impact of animal grazing. Four alder restoration areas and three spontaneous succession areas have been mapped with GPS equipment, the occurence of mature oaks, which could serve as a source of acornsg was also mapped on the dump and in surroundings. Most seedlings (657) were found in the succession and only 98 in alder reclamation, and the occurence in succession was statistically significantly more frequent. The number of seedlings from sources diaspors decreased, the longest distance was over 1300 meters. For three habitats (spontaneous succession, alder reclamation, open space with grass vegetation (Calamagrostis epigeios)) were planted 12 oak seedlings in fence and 12 seedlings outsider of the fence. Annual growth rate and survival of oak were evaluated using two-way ANOVA. Results showed that the area has a significant effect on the growth of oaks. In alder reclamation and the open area had a high mortality of seedlings and small increase, the fence does not have significant influence on these areas....
27

Bilance biogennich prvků rekultivovalých a nerekultivovaných výsypek / Nutrient budget in reclaimed and non reclaimed heaps

Veselá, Monika January 2013 (has links)
Extraction of mineral resources causes landscape degradation and the aim of reclamation efforts is to restore ecosystems. Our research was carried out on spoil heaps after brown coal mining near Sokolov (Czech Republic). We compared twenty years old spontaneously developed sites and reclaimed sites afforested by alders Alnus glutinosa and A. incana. Biomass and nutrient budget were evaluated for herbs and woody plants, separately for species Salix caprea, Populus tremula and Alnus glutionosa. Alder showed significantly higher concentrations of nitrogen and carbon compared to other tree species. The total amount of biomass, carbon and nitrogen was higher on reclaimed sites whereas phosphorus was more represented on spontaneously developed sites. Most of nitrogen was accumulated in the below-ground tree biomass and the largest amount of phosphorus was in the above-ground tree biomass. Woody plants of non-reclaimed sites produced more litter whilst litter of alder stands showed a higher concentration of nitrogen. Higher values of biomass, carbon and nitrogen of reclaimed sites were probably achieved through alder ability to fix atmospheric nitrogen.
28

Soft-sediment benthos of Aramoana and Blueskin Bay (Otago, New Zealand) and effects of dredge-spoil disposal

Paavo, Brian Lee, n/a January 2007 (has links)
Studies were conducted to broadly describe and understand the sediment benthos of a shallow-water coastal area (Aramoana Beach - Heyward Point - Blueskin Bay) near the entrance to Otago Harbour, a system largely representative for southeastern New Zealand. Benthic assemblages were examined in relation to gradients of wave exposure and disturbance, sediment type and bathymetry, and dredge-spoil disposal. Sediment and macrofaunal surveys in autumn and spring 2003 found little change in sediment texture gradients from historical studies and a lack of vertical stratification. Macrobenthic samples from spring produced significantly higher abundances of three numerically dominant phyla (Arthropoda, Annelida, and Mollusca) and higher taxon richness compared to autumn. Within water depths of 6-30 m, abundance, richness, and diversity increased with depth. Multivariate analyses identified similar assemblages among deeper sites, despite sediment textural differences, whereas distinct assemblages were found in the shallow portions of the three areas. Meiofaunal abundance patterns did not reflect those of macrofauna, possibly indicating greater vertical penetration of sediments in these hydrodynamic environments. Several new kinorhynch taxa were found. In a field manipulation, part of the Aramoana dredge-spoil dumpground was protected from spoil disposal for an extended period followed by experimental dumping of sandy and muddy spoil. Macrofaunal samples were collected before dumping and at nine sites < 119 d after disposal. Water velocities at the sediment-water interface were compared to a local sediment disturbance model. Dumpground samples were depauperate in individuals and taxa compared to an area protected from dumping for > 180 d. A drop in abundance and a dissimilar community coincided with muddy spoil, but fine sediments were dispersed within 26 d and macrofaunal assemblages recovered to the pre-existing state. Sandy spoil, while not altering native sediment textures, had a more prolonged impact due to transplantation of macrofauna from the dredged area that persisted for < 41 d after disposal. Side-scan sonar mapping indicated that the disposal footprint model used approximated the extent of sandy spoil impacts well, while local conditions spread muddy sediments beyond the initial impact site. A novel sediment profile imaging device was constructed that has many advantages over existing devices for spoil mound studies and habitat mapping: it is smaller, can be manually deployed from small boats, is cheaper, and can be modified to work in almost any soft sediment. Studies of one dominant taxon, the gastropod Zethalia zelandica, showed it was better able to survive sand burial than mud burial, did not vary in overall activity through a range of 5-14� C, and contributed a large proportion of biomass of its community. The spoil disposal strategy used does not appear as environmentally neutral as originally thought. Only muds are effectively dispersed whereas coarser sediments accumulate, affecting physical and biological benthic processes of a wider area. Two mitigation strategies were evaluated using a heuristic model. Reducing the disposal area and spreading mud disposal events over a longer time span may be an effective interim strategy. Overall, the studies will help guide management of the area.
29

中山先生考試制度之研究 / Dr. Sun Yat-Sen's Examination System

鄭幸怡, Cheng, Hsing Yi Unknown Date (has links)
「考試獨立」是中山先生五權憲法政治制度中,所提出的一項重要政治理念。其特色在於將人才政治的「人治」思想,納入現代「法治」思想的體系脈絡,成為「治人」與「治法」兼具的政治組織。   我國憲法,承襲中山先生的政治理念,成立五院制的中央政府體制,獨立設置「考試院」。近年由於「人事行政局」與「考試院」所引發的職權範圍之爭,而形成一股人事的憲政改革風潮,使「考試獨立」之意義歸趨模糊。任何一項政治制度組織,其建構的層次,總離不開政治文化面、法規面、實際運作面三種面向的解析。「考試獨立」之制度,亦不屬例外。本文之內容,即是準此三種面向,來探討中山先生「考試獨立」主張之主張之意涵。   首先以「人才政治」、「權能區分論」與「考試權之淵源」,探其基礎理論;並以中山先生之闡釋,明其內涵性質及思想背景;配合考試制度的發展概況,作一整體之觀察。
30

Inventory, Characterization, and Classification of Minesoils in the Big South Fork National River and Recreation Area

Jones, Cassi Savage 01 August 2011 (has links)
The aim of Part One was to discover and investigate the physical and chemical properties of coal minesoils occurring within the Big South Fork National River and Recreation Area (BSF) in order to better understand the nature of these anthropogenic soils. In particular, this information was to identify which, if any, un-reclaimed or recently reclaimed minesoils were actively producing acid mine drainage (AMD) and what properties were inhibiting revegetation. Historical knowledge and maps were used to locate more than 30 un-reclaimed and reclaimed minesoil sites, which were mapped with GPS. Soil profiles were exposed on 18 sites and grab samples taken on another 12. The morphological properties of each full profile were described according to the National Soil Survey Handbook and samples were taken from each horizon. Chemical properties analyzed for include: particle size, acid-base account, pH, exchangeable aluminum, manganese oxides, soil organic carbon, cation-exchange capacity, exchangeable bases, Mehlich I-extractable elements, and total elemental concentrations. Significant differences in the following properties (averaged) were discovered between the un-reclaimed and reclaimed minesoils: slope, percent rock fragments, dominant lithology, net neutralization potential, pH, extractable aluminum, base saturation, several Mehlich I-extractable nutrients and total elemental concentrations. Hierarchical clustering analysis revealed similar findings and also highlighted instances where reclaimed minesoils were statistically more similar to un-reclaimed minesoils than to other reclaimed minesoils. This indicated that reclamation efforts may not have been completely successful on these sites. In Part Two, minesoil profiles were classified according to Soil Taxonomy and according to proposed amendments by the International Committee for Anthropogenic Soils (ICOMANTH). The ICOMANTH amendments provided more informative classifications for coal minesoils in the BSF however, shortcomings were noted. Additional recommendations were made and the minesoils were again classified according to these recommendations. Compared to both the Soil Taxonomy and the ICOMANTH classifications, those according to the proposed additional amendments revealed more of the unique properties of the minesoils studied in this project. The results of this study can aid the National Park Service with future land management of the minesoils located within the BSF boundaries and other users of drastically disturbed minesoils.

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