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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.
321

Assessment of land use - land cover in relation to water quality in Beijing-Tianjin-Tangshan region: a case study in Wenyu River Watershed, Beijing. / CUHK electronic theses & dissertations collection

January 2011 (has links)
An examination of temporal and spatial variation of water quality across the whole watershed is undertook in this research. It is observed that the seasonal variation is apparent in all of the water quality parameters measured. And the spatial variation of water quality parameters gives us the general ideas that water quality is correlation with the watershed landscape. / An integrated approach involving Remote Sensing (RS) technology, Geographic Information System (GIS), Statistical and Spatial Analysis, as well as hydrologic modeling is put forward to perf0ll11 a comprehensive study on the relationship between land use-land cover and water quality in Wenyu River Watershed. Landsat TM data is used to extract land use-land cover information of the study area; while Arc Hydro model is employed to perform the stream network tracing and watershed delineation. / Based on an exponential model, separate multiple regression models are developed to estimate the contributions of different land types on six stream water quality variables, including TN, NO3- N, TP, PO4- P, COD and DO, in Wenyu River watershed. The resulted models are identified to well explain the water quality variables using land use types. And the goodness-of-fit of these modles are reasonably satisfactory. / Finally, this research also discusses the future-oriented studies: l) Higher resolution remote sensing imagery and more in-situ water quality data will be employed to improve the models with higher degree of "goodness of fit" in linking land uses and water quality. 2) Except LULC-related variables, other controlling factors will be considered to establish the more rigorous linkage models. 3) Identifying the relationship between the buffer landscape and stream water quality will be another subject of the future study. 4) Estimating the links between land use-land cover and water quality over an extended period is crucially important job in the future works. (Abstract shortened by UMI.) / The above results and analysis provide insight into the linkages between land-use practices and stream water quality, and the developed models can help in examining the relative sensitivity of water quality variables to alterations in land use made within a watershed. The predicted values are close to the actual monitored values, which indicates that with little calibration and validation, the regression model can be used in another watershed under a different geographical scale, in a different region with variable landscapes. / The results of water quality comparison between different land-use structures tell us that land use types are significantly correlated to water quality variables in Wenyu River Watershed. And the Spearman's rank correlation analyses verify this conclusion, and reveal that urban and village have strong positive relationships with the water quality variables of total nitrogen (TN), total phosphorous (TP), phosphate (PO4-P) and chemical oxygen demand (COD). On the contrary, forest land represents the negative correlation with all the above variables and only positively correlates with dissolved oxygen (DO), which demenstrates that forest land is acting as a "sink" or active transformation zone. / The study offers supporting evidence for previous studies and can serve as a reference to similar studies estimating the response of water quality to the land use-land cover change. The results also indicate that with the integration of GIS and ecological modeling, a decision-making support system can be developed to manage land development and control non-point sources pollution at the watershed scales. This study also suggests that if we pursue a sustainable development, the land management with respect to its development must consider the further erosion on water quality in this area. / Wang, Yufei. / Adviser: Yuanzhi Zhang. / Source: Dissertation Abstracts International, Volume: 73-06, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 123-136). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.
322

Impact of environmental expo on eight graders' self-perceived environmental behaviors

Borg, Laura Anne 01 January 2007 (has links)
This study sought to determine the impact of a free-choice environmental learning event on "at-risk" eighth graders' self-perceived environmentally responsible behaviors.
323

A study of the impact of anthropogenic activities in the Crocodile River, Mpumalanga

Soko, Mthobisi Innocent 25 November 2014 (has links)
In South Africa water is recognized as a crucial element in the battle against poverty, the cornerstone of prosperity, and a limiting factor to growth. The National Water Act 36 of 1998 recognizes that basic human and environmental needs should be met and that the use of water in all aspects must be sustainable. The Crocodile River (East) is situated in the north east of the Republic of South Africa and it is recognized as a stressed catchment in South Africa. The main impacts are domestic, industrial, agricultural, mining and afforestation activities. These activities pollute the river by discharging effluent as well as seepage from areas that support mining and intensive agriculture in to the river. The river catchment has been a center of research studies for many scientists either focusing on water quality or biological indicators separately. The aim of study was to determine the present ecological condition and the health of the Crocodile River. The objectives were to determine water quality status, identify possible sources of pollution and assess the spatial and temporal trends in ecological state. Fourteen monitoring sites were selected from the Crocodile River and its tributaries. The macro-invertebrates data were collected using the SASS 5 protocol and fish were collected using an electroshocker- catch and release method during high and low flow conditions of the year 2013. Water quality data was obtained by sampling using a polyethylene bottle from different sites within the Crocodile River and its tributaries from September 2012 until August 2013. The samples were analyzed by Mpumamanzi laboratory in Nelspruit and Waterlab in Pretoria. Additional water quality data was obtained from the Department of Water Affairs. Multivariate statistical methods were used to analyze all the data obtained. The multivariate statistical methods indicated that fish and macro-invertebrates species abundance, richness and evenness increase with the river flow distance downstream. Water temperature was one of the leading environmental variables for the structuring of fish and macro-invertebrates assemblage in the Crocodile River and its tributaries. A group formation of site during high and low flow condition by the Bray Curtis similarity and NMDS ordination indicated that many sites share similar macro-invertebrates or fish species. The one way ANOVA analysis indicated that there was no significance difference between macro-invertebrates richness and abundance during both flow conditions but there was a significance difference in fish richness and abundance between the two flow conditions. The PCA indicated that sodium has the highest physico-chemical impact amongst the physico-chemical parameters in the bi-plot followed by ammonium and nitrate. A correlation of physico-chemical parameters such as chlorine, total dissolved solid, electrical conductivity, sulphate and pH was observed. The levels of total dissolved solids and electrical conductivity were found to increase longitudinally as the river flows downstream. The dominance of single species within the macro-invertebrates and fish communities was an indication of imbalance of the communities within the sites. The presence of the macro-invertebrate family Beatidae and the fish species Chiloglanis pretoriae at sites CR3 and CR4 indicates a good water quality in the upper reaches during low flow condition as these species are sensitive to changes in water quality, while the presence of the macro-invertebrate family Pleidea and fish species Barbus viviparus at sites CR10 and KR1 during low flow condition indicated possible water pollution as these species tolerate changes in water quality and this was linked to the discharge of effluent from industrial, abandoned mines and run-offs from agricultural activities in the downstream reaches of the river. The low flow condition was dominated by sensitive species especially in the upper reaches than during high flow condition. The macro-invertebrates assessment index indicated that during low flow condition the Crocodile River was mostly at ecological class B (largely natural with few modification) above the Kwena dam, but from downstream of the dam the ecological category was in C class (moderately modified), while its tributaries are in ecological category B (largely natural with few modification). The fish response assessment index indicated that the ecological category for fish was mostly at C class (moderately modified) in the Crocodile River. The changes in macro-invertebrates communities and fish in the Crocodile River were believed to be associated with change of water quality and habitat modification due to flow modification. Agricultural activities in the upper reaches and a combination of industrial and mining activities in the middle and lower reaches of the Crocodile River were believed to be the sources of pollution that results in the change of water quality, fish and macro-invertebrates assemblage in the Crocodile River. Investing in the health of the Crocodile River is important for many Mbombela citizens and river dwellers as they rely on the functioning of the river for survival. / Environmental Sciences / M. Sc. (Environmental Science)
324

Examining the impacts of stream channelization on salmonid and aquatic invertebrate communities of a fifth-order montane river

Lennox, Preston A January 2012 (has links)
Stream channelization is a common form of anthropogenic disturbance, whose impacts on cold water salmonid communities have received little attention in comparison to the body of work demonstrating its negative effects on low land, warm water systems. Here, I compared the effects of stream channelization on fish and invertebrate communities and their habitats in disturbed and undisturbed cold-water mountain streams in southern Alberta. I demonstrate that stream channelization has imposed significant alterations to stream habitat, most notably a loss of deep habitat, and that these alterations have led to a statistically significant decline in abundance and biomass of Rainbow Trout and Mountain Whitefish, as well as a significant decline aquatic invertebrate biomass. Because of the importance of monitoring fish abundance in deep pools, I used snorkel surveys instead of electrofishing. In shallow, disturbed streams, however, snorkel surveys may be less effective and should be used with caution. / ix, 104 leaves : col. ill., col. maps ; 29 cm
325

An environmental history of the Mgeni river estuary : a study of human and natural impacts over time.

Glennie, Lauren. January 2001 (has links)
South African estuaries have high biodiversity value and provide many benefits to society, including food, real estate, a place for recreation and economic enterprise. However, they are facing growing human pressures such as urban encroachment, development in river catchments and interference in hydrological cycles. This dissertation provides an exploratory study of the environmental history of the Mgeni River Estuary, KwaZulu-Natal in an attempt to improve the understanding of the forces that drive environmental change. Through the application of the techniques and methodologies of environmental history, it explores the dynamics, characteristics and impacts of human interaction with the Mgeni River Estuary over time. It focuses on the emergence of a capitalist! industrial society in the twentieth century as this period has been characterised by the most significant environmental alteration and degradation. With the aid of the techniques and methodologies employed, the study highlights a complexity of natural and human events that have altered the estuary over time. Comparative analysis of aerial photographs between 1937 and 1996 reveals that physical changes to the estuary were linked to prevalent social and economic activities. The study describes cultural beliefs, modes of resource use and the political economy as significant and interwoven factors that facilitate environmentally intrusive activities. The study has provided insights into the complexity of factors that influence the rate and extent of change of an estuarine system. It concludes that to improve the understanding of the causes of environmental change, it is necessary to look further than the physical impacts on the environment to the attitudes and beliefs that underlie them. While the solutions to the problems facing the Mgeni River Estuary are not easily at hand, such analysis should assist policy makers and managers in finding a way to initiate more sustainable estuarine development in the future. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2000.
326

"Almost islands": A research synthesis of Aboriginal communities in Canada as metaphorical islands

Unknown Date (has links) (PDF)
The purpose of this study is to describe the geographic distribution of Aboriginal people who live in remote, isolated Aboriginal communities in Canada in terms of how geographic settings and features, particularly those that are characteristic of island dwellers, are related to and can impact aspects of culture and identity. Through this process, data was collected using a research synthesis, which allowed for a great deal of data from various sources to be analyzed, extracted, and coded. Based on this qualitative study, numerous geographic characteristics similar to those of islanders and islands emerged. Physically, islands and Aboriginal communities represent bounded, finite spaces that are located on the periphery and are impacted by isolation. These unique isolated areas allow for islanders and Aboriginal people to experience ethnic homogeneity and strong attachments to place, both of which allow for the preservation of culture and identity. That being said, islanders and Aboriginal people both experience migration as a way of life, and leaving their places of origin to experience life in larger, more diversely and densely populated areas is necessary for many. As a result of these findings, this study compares isolated Aboriginal communities in Canada and Aboriginal people to various small islands around the world as well as islanders, through various spatial metaphors.
327

Specifika telefonní krizové intervence obětem obchodu s lidmi / Requirements for telephone crisis intervention for victims of human trafficking

HONZÍKOVÁ, Eva January 2010 (has links)
The thesis topic ``Requirements for telephone crisis intervention for victims of human trafficking{\crq}q was chosen because of the author{\crq}s personal experience. The thesis aims to map out a comprehensive picture of a specialised helpline for trafficked persons and to compare its requirements with those of the helpline for the general public. Human trafficking is a criminal act which entails an abusive breach of human rights. Recent expansion in Europe is often connected with a specific migration situation, so it is a current topic. Human trafficking is widespread throughout the whole of the Czech Republic, and as the victim is prevented from moving freely and is torn from their familiar surroundings, it is important that they have unlimited access to a contact. For that reason, initial contact with victims of human trafficking is often made through telephone crisis intervention, which must be highly professional. The working theory deals with telephone crisis intervention, human trafficking, workers and clients. It explains TCI in the context of clarification of formats and different types of services. Online counselling is described further, help-line working methods are clarified and the basic service principles are outlined. Another area of focus is help-line workers and their training, cooperation and supervision. The next chapter concerns human trafficking and explores legislative problems, the human trafficking mechanism, forms, routes, causes and consequences. The final aspect is clientele, and explains the use of the term trafficked person and victim of human trafficking, and describes the risks to clients who contact help-lines. The aims of this thesis were to clarify the characteristics of telephone crisis intervention for issues of human trafficking; to compare the conditions of a worker dealing with specialised telephone crisis intervention with general telephone crisis intervention for the whole population; to map out the working procedures within telephone crisis intervention; to map out the working procedures within online counselling. The author believes that aims of the thesis were met. Qualitative research was used to achieve the aims of the thesis. Data was obtained through interviews conducted by the author. The data gathering technique used was to conduct a semi-structured interview with open question. The interviews lasted for approximately one hour and were composed of two parts. The research sample included two groups of participants {--} workers providing telephone crisis intervention services. The first group was made up of 10 workers who work on specialised help-lines directed at human trafficking. The second group was comprised of 10 workers providing telephone crisis interventions for the general populace. The author formed three hypotheses based on the results of this qualitative research. There is the same need to complete the basic course of crisis intervention for consultants working on the ordinary help lines as for the consultants working on specialised help lines. Consultant on specialised help lines is more focused on providing a service of legal information than the consultant working on the ordinary help lines. Younger help-line consultants on the help lines for victims of trafficing don't see exactly the specifics of that line. The author believes that the work could be useful for organisations providing specialised help-lines for victims of human trafficking.
328

Tree Growth and Spatial Pattern in Two Forest Park Permanent Plots: A Look at Stand Composition and Condition

McDonald, Hannah Beth 01 January 2011 (has links)
In June of 2010, two permanent research plots were established in Forest Park, based on their differing proximities to downtown Portland, Oregon. As part of a long-term ecological research project that seeks to explore the ecological status and human thumbprint on this 5,100 acre forested reserve, the 2010 tree data was investigated for emergent compositional and spatial patterns. Stand composition, tree size, growth rates, and spatial patterns were analyzed, along with ecological and land use histories. Results indicate that the Balch plot, more closely located to the urban center, has different stand composition, condition, and vegetation growth rates, compared to the more rural Miller site. This study supports findings from a study done by Broshot in 2009, where more urban plots demonstrate a different stand composition and recruitment pattern than rural sites. The study is an initial step for exploring questions regarding the ecological status of Forest Park and how land use and disturbance, past and present, shape Portland's forested reserve.
329

An environmental parameters descriptor

Robbins, Claude Lee. January 1978 (has links)
Call number: LD2668 .T4 1978 R62 / Master of Regional and Community Planning
330

Past adaptive patterns in western Papagueria: an archaeological study of nonriverine resource use

Doelle, William Harper January 1980 (has links)
No description available.

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