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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.
711

Concentrations and distribution of persistent organic pollutants in sediments of Er-ren River

Ting-chung Lee, Lester 07 September 2011 (has links)
Persistent organic pollutants (POPs), which include polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs), are widely distributed in the environment. Some investigations have demonstrated that these pollutants will cause potential impacts such as carcinogenic and mutagenic for human health. In this study, we analyzed the concentrations and distributions of PAHs and PCBs in sediments of the Er-ren River, as well as the relations with total organic carbon (TOC) and particle sizes. Several molecular ratios were utilized to distinguish the major sources in this study. Results showed that PAH and PCB concentrations in Er-ren River ranged from 12.1 to 1460 and 0.45-591 (ng/g dw), respectively. The maximum concentrations of PAHs and PCBs were mostly found in sediments from Sanyegong River. In comparison with other studies all over the world, the concentrations of PAHs in this study were between low and mid-low levels. PCB concentrations in sediments of the Er-ren River were lower than those reported from previous studies. PAH and PCB concentrations showed no significant correlation between TOC and particle size. Petrogenic and petroleum combustion origin were the main sources of PAHs in sediments of Er-ren River In addition, perylene was the most dominant compound in Er-ren River, suggesting that it could be a useful indicator to differentiate various PAH sources in sediments. The results of hierarchical cluster analysis (HCA) and principal components analysis (PCA) indicated that PAH groups were clustered based on the loading of perylene, while PCB groups were clustered by the compositional homologues of PCBs. Comparing with sediments quality guidelines (SQGs), the PAH concentrations in all the sampling sites were below ERL value, suggesting that few adverse ecological effects would arise from the PAHs. However, the PCB concentrations in 14 sampling sites ranged between TEL and PEL values, indicating that adverse effects could arise for benthic organisms. The £UESBTUFCV of PAHs and the toxic equivalents (TEQ) of PCBs were both lower than quality values reported, suggesting that adverse ecological effects might be not expected.
712

Managing the Yellowstone River System with Place-based Cultural Data

Hall, Damon M. 2010 August 1900 (has links)
This project aims to create new research tools within the human dimensions (HD) of the natural resources field to improve environmental policy decision making. It addresses problems that arise from the recent trend towards decentralized natural resource management (NRM) and planning (e.g., community-based planning, watershed-based and collaborative management, others). By examining one decentralized riparian management planning effort along the Yellowstone River (Montana), this study finds that decentralization forces new needs such as localized information requirements and a better understanding of the rationales behind local interests. To meet these new scale demands and to ensure that policy best fits the social and biophysical settings, this project argues that local cultural knowledge can serve as an organizing framework for delivering the kinds of understanding needed for decentralized planning. This was tested by interviewing 313 riverfront landowners, recreationalists, and civic managers to understand how residents conceptualize the river’s natural processes, its management, and their desires for the future of the river. Analysis of the transcribed in-depth interview texts—the Yellowstone River Cultural Inventory (YRCI)—found that: (1) altering decision venues places more significance upon interpersonal working relationships between managers and citizens; (2) while local expertise can provide higher quality information to managers, local decision making cultures still retain power dynamics that can inhibit or advance conservation policies; (3) how natural resource places are symbolically communicated has a material impact upon resource uses; (4) how residents conceptualize the ownership of land is complicated along a dynamic river; and (5) this dynamism impacts planning efforts. In sum, this project argues that for social research to provide the data and analysis appropriate, a modification in scale and a commensurate shift in the lenses used for social inquiry is necessary. An in-depth understanding of local cultures—like the YRCI—enables agencies to best manage in decentralized scales of planning by calling attention to site-specific nuances such as power dynamics and place representation which are often missed in traditional large-scale HD methods and lenses. This research also functions as a preemptive way to engage the public in environmental planning helping decision makers’ best fit policy to particular socio-cultural and ecological settings.
713

A Study on the City Image of Kaohsiung City- A Case Study of Love River

Cheng, Meei-yuan 30 June 2005 (has links)
To enhance the living quality and tourism, Taiwan government encourages countries and cities to held more colorful activities of local festivals, which can draw a big crowd of foreign sightseers and prosper local economy. Taiwan is abundant in folk cultures; therefore, most local governments is actively promoting some place marketing programs rich in local characteristics, such as ¡§Love River Lantern Festival¡¨, ¡§Tungkong Tuna Cultural Festival¡¨, ¡§Machu Cultural Festival¡¨, ¡§The Yenshui Fireworks Festival¡¨, and ¡§Chamomile Blooming Season¡¨. The above cultural activities are well known not only islandwide but also worldwide. For the past few years, Kaohsiung City government has been deliberately shaping the city with ¡§water¡¨ and ¡§light¡¨. Love River is generally acknowledged as the most representative symbol of Kaohsiung. Nowadays, Kaohsiung has become one of the most beautiful cities in Taiwan and Love River should take most of the credits. Besides, this successful city marketing experience of Kaohsiung now is the legend in Taiwan. This study is based on two theories¡Ð¡§Place Marketing Theory¡¨ and ¡§City Image Theory¡¨. By reviewing lots of literature, summarize some factors, criteria, and alternatives that may be related to Love River environmental image. Then, through in-person expert interviews and questionnaire survey, apply AHP (Analytic Hierarchy Process) to sort out the priorities of the factors, the criteria, and the alternatives. The outcomes are as follows: 1.The priorities of the three factors on the second layer are¡Ð¡§Specific Architecture Clusters¡¨ goes first, ¡§Blue & Green Belt System¡¨ second, and ¡§ Traditional Cultural Festivals¡¨ last. 2.The priorities of the twelve criteria on the third layer are¡Ð ¡§River-Bank Facilities¡¨ goes first, ¡§Culture Heritage And Historic Sites¡¨ second, ¡§Riverfront Parks¡¨ third, ¡§River Channels¡¨ fourth, and ¡§Bridges¡¨ fifth. 3.The priorities of the three alternatives on the fourth layer are¡Ð ¡§The symbol of Kaohsiung Area¡¨ goes first, ¡§Promotion Of Local Tourism and Food & Drink Industry ¡¨ second, ¡§Love River Carnival¡¨ last.
714

Denudation and Transport of Terrestrial Materials from the Kaoping River Watershed

Yang, Jang-Yi 13 September 2001 (has links)
Abstract Resent studies have demonstrated that rivers in the western Pacific islands can be very important in affecting global riverine material flux. The Kaoping River is a typical tropical, island-type river with the largest drainage area in Southern Taiwan. Material outputs from the Kaoping River are expected to play a major role in affecting the local coastal environment. Therefore, this study aims at understanding processes and mechanisms for generation, transport and transformation of terrigenous materials in the Kaoping drainage basin. The temporal and spatial distributions of hydrochemical parameters, total suspended matter (TSM), major ions, nutrients, and particulate and dissolved species of C, N and P (DOC, DIN, DIP, DON, DOP, POC and PON) were measured in the Kaoping River from August 1999 to August 2000. The collected data are used to elucidate sources and the influence of external forcing on fluxes of sediment, carbon and nutrients form the Kaoping drainage basin. Based on the fluxes of TSM and total dissolved solid (TDS) observed in the Kaoping River, the total, physical and chemical weathering rates were estimated about 7,368, 5985 and 1,383 g/m2/yr, respectively. The significant correlation between TSM-load and water discharge suggested that the sediment flux was primarily controlled by the runoff in the drainage basin. The generation of total carbon (DIC¡ÏDOC¡ÏPIC¡ÏPOC) in the Kaoping drainage basin was about 191g C/m2/yr. The yields of DIC, DOC, PIC and POC were 110 (60%), 2.27 (1.7%), 35.6 (17%) and 42.6 (21%) g C/m2/yr, respectively. These values of carbon yield from the Kaoping drainage basin were very high in comparison with ones obtained from the Lanyang River and the other major rivers in the world. The annual fluxes of riverine DIC, DOC, PIC, POC and TC from the Kaoping River were about 34.5, 0.705, 11.0, 13.2 and 63.2 x 1010 g C, respectively. Regarding the nutrient results, the riverine fluxes of dissolved and particulate nitrogen were 2.298 x 109 mole/yr and 1.55 x 108 mole/yr, respectively. By taking out the natural input of total dissolved nitrogen, anthropogenic input of total dissolved nitrogen in the Kaoping River was about 5-6 x 104 kg/day that is similar to the one (56,779 kg/day) reported by the EPA. The fluxes of total dissolved phosphate and silicate were 3.378 x 107 and 1.285 x 109 mole/yr, respectively. The high riverine flux of silicate also reflects the high weathering rate in the Kaoping drainage basin. The flux of anthropogenic phosphate from the Kaoping River was about 4 - 8 x 103 kg/day which was similar to that estimated from the Tanshui River. Taking the nutrient content in the Kaoping upstream as background level, the natural fluxes of total nitrogen and phosphate in the Kaoping River were estimated to be 8 x 103 and 4 x 103 kg/day which were equivalent to 16% and 57% of the anthropogenic inputs, respectively. Anthropogenic input appears to be the major source of riverine nutrients in the Kaoping River. Overall, human activities play a major role on affecting the generation, transport and transformation of terrigenous materials in the Kaoping drainage basin. This study also confirms that rivers in Taiwan may be very important in affecting the local and/or the global fluxes of terrestrial materials.
715

Investigation of industrial wastewater and treatment facility performance of A-gong-dian river basin

Li, Tsai-yu 04 July 2009 (has links)
The water quality of rivers currently is seriously polluted in Taiwan for influencing drinking water quality, harming onto plants growth caused soil pollution problems by using river irrigation and harming the human health indirectly by contamination in river sediments. In this work, we will investigate the area of river water quality characteristics and pollution sources to solve effectively for the pollution problems in the river area of A-Gong-Den in Kaohsiung County. The source of the river area of this study is dam of A-Gong-Den. Their water quality is polluted majorly by the domestic and industrial wastewater. The dark red-color of river body was due to the effluent from those industrial factories. Heavy metals such as Zn, total Cr ions and conductivity were all over the water quality standard of irrigation uses. Thus, we will try to improve the color problems in this area of river by diagnostics method in five factories having wastewater treatment plants. The effective solution in management and controlling will be discussed. We investigate the treatment facilities and performance evaluation in five industrial plants. We found the wastewater treatment and operation technology should be done and elevated in some factories. Importantly, the marked signs in pipelines in wastewater treatment were not clear and operated under not normal conditions. The EPA in county should send officers for checking the operations of the wastewater treatment plants in listings with a normal period for once.
716

The influence of the Platte River upon the history of the valley,

McKinley, John Lawrence. January 1900 (has links)
Thesis (Ph. D.)--University of Nebraska, 1935. / Bibliography: leaves 132-138.
717

Solid peroxide stimulated phenanthrene removal from contaminated river sediment

Schaffnit, Katherine Stuart. January 2009 (has links) (PDF)
Thesis (M.S. in environmental engineering)--Washington State University, December 2009. / Title from PDF title page (viewed on Jan. 14, 2010). "Department of Civil and Environmental Engineering." Includes bibliographical references (p. 41-42).
718

Spatial and temporal patterns of the Bank Swallow on the Sacramento River

Garcia, Dawn. January 2009 (has links)
Thesis (M.S.)--California State University, Chico. / Includes abstract. "Located in the Chico Digital Repository." Includes bibliographical references (p. 74-80).
719

The Hocking Valley Coal Miners' Strike, 1884-1885 /

Lozier, John William, January 1963 (has links)
Thesis (M.A.)--Ohio State University, 1963. / Available online via OhioLINK's ETD Center
720

Die Stellung des Rheinlandes zur Schutzidee in der preussischen Wirtschafts- und Sozialpolitik von 1815 bis um die Mitte des 19. Jahrhunderts

Paulus, Otto, January 1927 (has links)
Thesis--Cologne. / Cover title. Vita. Includes bibliographical references (p. [4]-5).

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