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Watershed Management to control Pollution in the Ayuquila River, Jalisco, MexicoMartinez Rivera, Luis Manuel 01 May 2004 (has links)
The Ayuquila River watershed is important to western Mexico because of its biodiversity, physiography, fisheries resources, and water production. However, human activities are continuingly affecting natural resources within the basin. Soil erosion, as result of land use change, agriculture in steep land, extensive grazing activities and forest fires; and water diversion and pollution of the Ayuquila River are two relevant issues that have affected the natural resources of this watershed.
This river system plays an important role in wildlife conservation, containing 29 fish species, of which 12 are found inside the BRSM. The River also contains nine species of crustacean, one that is endemic to Jalisco State. The otter (Lontra longicaudis), a species threatened within the BRSM, is found in the Ayuquila- Armeria River watershed.
This research focused on the reduction of river pollution and the reduction of negative impacts of water pollution delivered to those communities, some of the poorest in the state of Jalisco, that live downstream of the valley. This research was also designed as a way to increase the knowledge of soil erosion processes and water quantity and quality in tropical environments and to test and develop new tools that might facilitate parameter estimation and predictive capabilities within the Ayuquila River watershed. Research efforts in this dissertation had focused on the development of new scientific information about point and nonpoint-source pollution within the Ayuquila River based on three main research studies, the investigation into trail erosion, the production of an erosion sensitive map, and documenting and modeling water quantity and quality in the Ayuquila Watershed.
Major concerns that this research seeks to contribute a solution, is to reduce negative impacts on public health, degradation in fisheries resources as source of local food supply, domestic water supplies for those communities, some of the poorest in the state of Jalisco, that live downstream the valley and that do not receive any benefit from the economic development of the Autlan- El Grullo Valley.
Results from the commercial trail study, with sediment productions close to 100 ton/ha/yr, showed the importance of the application of conservation practices to reduce the potential erosion from commercial trails in my study area and potentially other tropical forests of Latin-American. The WEPP model used to predict soil erosion in the tropical mountain environments of Mexico was shown to be an adequate tool even with WEPP's limitations for tropical soil environments. WEPP effectively contributed to the estimation of sediment plume production on trails, detected vegetation type differences in runoff and soil erosion, predicted the amount of rainfall as runoff well, and adequately developed soil erosion sensitive maps. Water diversion and pollution within the Ayuquila River are important sources of disturbance in the ecological conditions of riparian ecosystems. These two impacts cause a potential break in the ecological continuity of the Ayuquila River. Water quantity and quality modeling will provide opportunities for discussion and analysis of alternatives to water management and possible impacts to the river.
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Environmental Assessment of Streams: Linking Land Use, Instream Stressors, and Biological Indices to Infer Likely Causes of Ecological ImpairmentVander Laan, Jacob J. 01 May 2012 (has links)
To protect and restore the biological integrity of streams, we need to be able to both detect biological degradation and infer likely causes of impairment. Managers often use biological indices to measure biological condition and detect degradation. However, the ability to detect degradation can be limited by the performance of the indices we develop. Index performance varies widely, but the sources of this variation are often unclear. In addition, although bioassessments are useful tools for detecting biological degradation, they do not identify stressors associated with impairment. My thesis research had two general goals: 1) develop statistically and ecologically robust indices to measure biological condition in Nevada streams and 2) quantify relationships between land uses, stressors, and biological condition to infer likely causes of degradation.
I developed two biological indices for Nevada streams, a multimetric index (MMI) and observed to expected (O/E) taxa ratios, and determined if index performance was related to site isolation and sample evenness. The Nevada O/E indices were relatively imprecise compared with those from other regions, which likely results from low assemblage predictability associated with spatial isolation of aquatic habitats in arid regions. In contrast, the Nevada MMI was more precise than most previously developed MMIs, likely the result of using models to reduce natural variation in index scores. Sample evenness was positively associated with both O/E and MMI scores. Adjustments of index scores for sample evenness increased index precision, but also altered relative differences in index values and therefore inferences of biological impairment at specific sites.
I also quantified relationships between biological condition, instream stressors, and land uses and used a weight of evidence approach to infer likely causes of degradation. Land uses such as agriculture, urbanization, and mining were associated with the spatial distributions of instream stressors, and these stressors were associated with variation in biological condition. Total dissolved solids and metal contamination were the stressors most strongly associated with biological condition. By detecting biological degradation and identifying important stressors and their potential sources, the tools I developed should help managers target conservation and restoration efforts and improve their ability to protect freshwater resources.
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The Influence of Geology and Other Environmental Factors on Stream Water Chemistry and Benthic Invertebrate AssemblagesOlson, John R. 01 May 2012 (has links)
Catchment geology is known to influence water chemistry, which can significantly affect both species composition and ecosystem processes in streams. However, current predictions of how stream water chemistry varies with geology are limited in both scope and precision, and we have not adequately tested the specific mechanisms by which water chemistry influences stream biota. My dissertation research goals were to (1) develop empirical models to predict natural base-flow water chemistry from catchment geology and other environmental factors, (2) extend these predictions to nutrients to establish more realistic criteria for evaluating water quality, and (3) test the hypothesis that catchment geology significantly influences the composition of stream invertebrate assemblages by restricting weak osmoregulators from streams with low total dissolved solids (TDS). To meet goal 1, I first mapped geologic chemical and physical influences by associating rock properties with geologic map units. I then used these maps and other environmental factors as predictors of electrical conductivity (EC, a measure of TDS), acid neutralization capacity, and calcium, magnesium, and sulfate concentrations. The models explained 58 – 92% of the variance in these five constituents. Rock chemistry was the best predictor of stream water chemistry, followed by temperature, precipitation and other factors. To meet goal 2, I developed empirical models predicting naturally occurring stream total nitrogen and total phosphorus concentrations. These models explained most of the spatial variation among sites in total nitrogen and phosphorus and produced better predictions than previous models. By determining upper prediction limits that incorporated model error, I demonstrated how predictions of nutrient concentrations could be used to set site-specific nutrient criteria and accounted for natural variation among sites better than regional criteria. To meet goal 3, I experimentally manipulated (high and low) EC in both stream-side and laboratory flowthrough microcosms and measured survival, growth, and emergence of 19 invertebrate taxa. Observed variation among taxa in survival between treatments predicted taxon EC optima estimated from field observations (r² = 0.60). Taxa with the greatest differences in survival between treatments also had the highest EC optima, indicating that the inability to persist in low EC likely restricts the distributions of some taxa.
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Twentieth Century Channel Change of the Green River in Canyonlands National Park, UtahWalker, Alexander E. 01 December 2017 (has links)
Since the early 20th century, river channels of the Colorado River basin have narrowed, decreasing available riparian and aquatic habitat. Changes are considered to be the result of three major factors: wide-spread water development, increasing hydroclimate variability and the invasion of non-native tamarisk (Tamarix spp.), altering flow regime and sediment supply. Different studies have reached different conclusions about the relative roles of flow regime, sediment supply and tamarisk in causing narrowing.
I investigated channel change in the lower Green River within Canyonlands National Park to describe channel changes in the 20th century and understand the roles of shifting flow regime and changing vegetation communities on 20th century channel narrowing.
The lower Green River within Canyonlands National Park has narrowed substantially since the late 1800s, resulting in narrower channel. Changes to flood magnitude, rate and timing since 1900, driven by increased water storage and diversion in the Green River basin and declines in annual precipitation, was responsible for inset floodplain formation documented in this study.
I used multiple datasets to reconstruct the history of channel narrowing in the lower Green River and identify processes of floodplain formation. In the field, analyses of a floodplain trench were described to identify rate, timing and magnitude of floodplain formation. Channel and floodplain surveys were conducted to determine possible changes in bed elevation. Additionally, I analyzed existing aerial imagery, hydrologic data, and sediment transport data. I applied these techniques to determine how floodplain formation occurred at multiple spatial and temporal scales.
My investigation shows that the floodplains of the contemporary lower Green River began forming in the late 1930s and continued to form in the 20th century by inset floodplain formation. During this time period, peak flow and total runoff declined due to climatic changes and human water development. Since the mid-1980s, inset floodplains continued to develop along the lower Green River since the mid-1980s, narrowing the river by an additional 9.4%. Analysis of aerial imagery shows that changes to the floodplain identified in the trench occurred throughout the 61 km of river I studied. Non-native tamarisk (Tamarix spp.) did not drive channel narrowing, though dense stands stabilized banks and likely promoted sediment deposition. Inset floodplain formation reflects changes to flooding resulting from water development and climate change.
My findings have implications for the long-term management of the lower Green River and endangered endemic native fishes –particularly the Colorado pikeminnow (Ptychocheilus lucius) and the razorback sucker (Xyrauchen texanus). Collaboration with upstream stakeholders and managers is necessary to preserve elements of the flow regime that preserve channel width and limit channel narrowing.
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Expatriate selection, training, family issues and repatriation putting theory into best practice for expatriate success in Australia, Singapore and MalaysiaNeilson, George A. January 2002 (has links)
For both large and small companies involved in the internationalisation of world-wide markets, the successful management of expatriate assignment is an important part of overseas commercial activities.This investigation was concerned with expatriate management in fifty, multinational and international organisations in Australia, Singapore and Malaysia to contribute to the enhancement of success and reduction of failure of expatriate assignments.Data was collected to heighten the awareness of practitioners and academics to the value of dealing differently with expatriates. In forecasting the value of expatriates and the importance of global trade in the future, it was shown that the most successful companies are those able to identify and select an ample number of appropriate international managers. Where suitable candidates for relocation are not selected, higher than normal turnover occurs.The unique Australasian models developed and tested in this thesis are a direct response to the results of current research and encourage current practice to be less static. resulting in the rate of expatriate failure being reduced substantially.
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Modelling Fertiliser Use in the Glenelg Hopkins CatchmentSchlapp, Julia Emily, julia.schlapp@rmit.edu.au January 2009 (has links)
The improvement of water quality in the streams of the Glenelg Hopkins catchment is a priority of the Glenelg Hopkins regional strategy. A major source of water pollution in the region is linked to agricultural activities as high nutrient levels from runoff have the potential to increase the incidence of blue-green algae in the waterways. Land use change, reduced rainfall, more frequent extreme rainfall events and higher temperatures associated with climate change are likely to exacerbate this trend. Water testing data of the Total Phosphorus (TP) levels in the Hopkins River and at other sites within the Hopkins Catchment indicate increasing incidence of TP above the Environment Protection Authority's target levels for extended periods of each year. Earlier research indicated that phosphorus in runoff increases when pasture fertility increases and that fertiliser management practices should be considered as an element of preventative action for reducing nutrient pollution. During our research, a survey was undertaken in the Hopkins River catchment, to determine the current management of phosphorus (P) fertilisers on grazing and mixed enterprise farms, the attitude of farmers to natural resource management and their understanding of nutrient pollution. The survey also gathered information on the way farmers made fertiliser management decisions. If cooperation relating to phosphorus fertiliser application could be facilitated between groups of farmers, it may be possible to reduce nutrient runoff into the Hopkins waterways. Cooperative game theory has successfully been used worldwide in the resolution of environmental problems where there is an economic impact to the decision making process. In this project, the amount of phosphorus applied per hectare was used in a cooperative game theory model assessing the potential for cooperative action on phosphorus management by groups of farmers, based on the trade off between the economic cost of pollution to the region waterways and the economic production benefits to the individual. The outcome of this work was individual optimal strategies for fertiliser application, allowing individual farmers to reduce their impact of agricultural production on the health of the catchment. Involving the farmer groups, while undertaking the project, raised awareness amongst the farming population of the regional nutrient pollution caused by runoff from agricultural land, and enlisted their assistance towards adopting a cooperative approach to the problem. In addition, the results have been mapped using a Geographical Information System (GIS) for visual presentation and to demonstrate the use of this process in natural resource management with the farmer groups.
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Evaluating the Effectiveness of Conformance-Based Plans: Attributing Built Heritage Outcomes to Plan Implementation Under New Zealand's Resource Management ActMason, Greg January 2008 (has links)
Little is known about the effectiveness of district plans in protecting built heritage, which is a matter of national importance under New Zealand's Resource Management Act 1991 (RMAct). This is despite the fact that the RMAct directs planning agencies to evaluate the effectiveness of plan provisions. This lack of evaluation is not unique to New Zealand or merely symptomatic of heritage planning. Instead, it is a shortcoming in planning theory and practice internationally; a well recognised impediment being that planning lacks a suitable evaluation approach. This thesis aims to address this deficiency by proposing a methodology for evaluating plan effectiveness and applying it to the built heritage provisions of two district plans. The methodology adopted has been shaped by the theory-based and realist evaluation approaches, as developed in the field of programme evaluation. Both approaches share a common ontology regarding claims of causality, which stresses 'knowledge in context'. Thus, a central endeavour of the research is not only to identify the environmental outcomes arising from plan implementation, but also to understand how and why the implementation context promoted or inhibited the achievement of plan goals. In so doing, the causal and implementation theories underpinning the plans' heritage provisions are exposed, modelled and tested. The findings reveal that plan implementation failed to prevent the loss of built heritage values in many instances. While the plans' causal theory was largely sound, key aspects of the implementation theory were not realised during the development control process. Plan quality was a significant factor, as was the commitment and capacity of developers to comply with the plans. The institutional fixation on consent processing speed rather than environmental outcomes was a further impediment. Overall, the theory-based approach provided a useful framework for determining plan effectiveness and holds promise for evaluating plan issues other than built heritage.
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Quality of Heterogeneous Services with Distributed Resource Management for a WCDMA UplinkDas, Pratik January 2006 (has links)
A radio resource management scheme for WCDMA uplinks is proposed that manages quality of service (QoS) for heterogeneous services whilst maintaining high channel utilisation efficiency. The proposed system is partitioned into the 3 modules, viz. a QoS-sensitive rate scheduler, an inter-service and intra-service user prioritisation schemes, and a frame admission controller for dynamic resource reallocation. Users are allocated the minimum resources required to manage their QoS requirements through just-in-time delivery of payload, leaving more room for best-effort service users. The transmission urgency of each user is estimated by the rate scheduler based on a target transmission delay - a unique parameter used in the proposed resource management strategy to enable just-in-time payload delivery, service differentiation, and uncomplicated mapping of application requirements to QoS parameters. Transmission rate change requests from the rate schedulers are collectively processed through inter-service and intra-service priority queuing in a manner that is shown to exhibit fairness in allocation of resources amongst users of a heavily loaded network. The performance of the proposed strategy is explored through discrete-event simulations for 3 classes of traffic - voice, video and data, over the WCDMA uplink in the presence of short-term Rayleigh fading, ARQ, FEC, target transmission delays and FER targets in a multi-cell environment. Two alternatives for distributed resource management have been studied, with the UE or Node-B in control of resource allocation. The UE controlled resource management system is shown to achieve higher channel utilisation efficiency at the cost of fairness. The Node-B controlled resource manager respects the priority of speech, video and data traffic in heavily loaded systems, as reflected in 95 percentile packet transmission delays. / PhD Doctorate
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Human resource management in the hotel industry in TaiwanYang, Hui-O, n/a January 2007 (has links)
This thesis examines contemporary human resource management (HRM) in the hotel industry in Taiwan. The hotel industry and the effective management of its human resources are of great economic significance for Taiwan, given the government's plans for doubling the number of international arrivals between 2002 and 2008 (Tourism Bureau 2005b). Yet previous research on this topic is scarce, consisting of only four studies, three of them unpublished Master's theses. Access to two of the studies is limited and all four studies have adopted a 'single issue' perspective in their investigation. This study has attempted a broader perspective, inviting exploration in an open-ended way of a range of contemporary issues and concerns. It also offers a literature review intended as a significant contribution in its own right, in its attempt to locate research helpful to the Taiwanese hotel industry.
The specific aims of this study were to explore the way managers in the hotel industry are thinking about what they identify as concerns, the HRM issues and practices they perceive as important in employee management, and the future plans they have for HRM. The data were gathered from the manager which each hotel identified as being best placed to discuss these issues. Findings from this study are presented with interpretation and commentary offered to compare the themes raised in this study with those identified in the literature.
Given the high proportion of quantitative studies in hospitality industry research across the world (Lucas and Deery 2004), a qualitative method is utilised in this research and in-depth interviews were chosen as the main vehicle for data collection. The characteristics of such qualitative research are exploratory and descriptive, creating a data set that is not possible to obtain through written questionnaires and surveys. Twenty-eight hotels were approached and fourteen hotels participated in this research, representing a 50 per cent response rate.
The results suggest that most participating hotels are focused on dealing with the day-to-day operational challenges of shortages of appropriately skilled staff, seasonal variations in workforce demand and employee turnover. While they perceive these issues as significant and challenging, they were mostly inclined to view these as 'facts of life' in the industry, and were relatively limited in their thinking about more fundamental and strategic solutions for dealing with them. However, some hotels are developing more innovative approaches to effectively engaging with these challenges, such as participating in joint-training programs with other hotels; developing long-term relationships with internship students; increasing employee empowerment and using the Balanced Scorecard (Nair 2004; Niven 2006) in performance management.
This study explores some ways in which these practical initiatives could be taken further. It also takes up a key theme which emerged from the interviews, namely the vital importance of developing sound customer service cultures and practices. Some practical ideas are explored to assist in this respect. On the bases of these findings, this study also concludes that human resource managers have a valuable role to play in the executive management teams of hotels. This role needs to be further developed and encouraged. The current and emerging challenges facing the industry demand an approach to HRM which is far more strategic than the traditional focus of personnel administration; instead, HRM has a key role to play in creating and sustaining competitive advantage in organisations.
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Power and politics in a system implementation.Peszynski, Konrad Janusz, mikewood@deakin.edu.au January 2005 (has links)
The central concern of this study is to identify the role of power and politics in systems implementation. The current literature on systems implementation is typically divided into two areas, process modelling and factor based studies. Process modelling classifies the implementation into a linear process, whereas factor based studies have argued that in order to successfully implement a system, particular critical factors are required. This literature misses the complexities involved in systems implementation through the human factors and political nature of systems implementation and is simplistic in its nature and essentially de-contextualises the implementation process.
Literature has investigated some aspects of human factors in systems implementation. However, it is believed that these studies have taken a simplistic view of power and politics. It is argued in this thesis that human factors in systems implementation are constantly changing and essentially operating in a dynamic relationship affecting the implementation process. The concept of power relations, as proposed by Foucault (1976, 1977, 1978, 1980, 1982), have been utilised in order to identify the dynamic nature of power and politics. Foucault (1978) argued that power is a dynamic set of relationships constantly changing from one point in time to the next. It is this recognition that is lacking from information systems. Furthermore, these power relations are created through the use of discourse. Discourse represents meaning and social relationships, forming both subjectivity and power relations. Discourses are also the practices of talk, text and argument that continuously form that which actors speak.
A post-structuralist view of power as both an obvious and hidden concept has provided the researcher a lens through which the selection and implementation of an enterprise-wide learning management system can be observed. The framework aimed to identify the obvious process of system selection implementation, and then deconstruct that process to expose the hegemonic nature of policy, the reproduction of organisational culture, the emancipation within discourse, and the nature of resistance and power relations. A critical case study of the selection and implementation of an enterprise-wide learning management system at the University of Australia was presented providing an in-depth investigation of the implementation
of an enterprise-wide learning management system, spanning five years. This critical case study was analysed using social dramas to distinguish between the front stage issues of power and the hidden discourses underpinning the front stage dramas. The enterprise-wide learning management system implemented in the University of Australia in 2003 is a system which enables academic staff to manage learners, the students, by keeping track of their progress and performance across all types of training activities.
Through telling the story of the selection and implementation of an enterprise-wide learning management system at the University of Australia discourses emerged. The key findings from this study have indicated that the system selection and implementation works at two levels. The low level is the selection and implementation process, which operates for the period of the project. The high level is the arena of power and politics, which runs simultaneously to the selection and implementation process. Challenges for power are acted out in the front stage, or public forums between various actors. The social dramas, as they have been described here, are superfluous to the discourse underpinning the front stage. It is the discourse that remains the same throughout the system selection and implementation process, but it is through various social dramas that reflect those discourses. Furthermore, the enactment of policy legitimises power and establishes the discourse, limiting resistance. Additionally, this research has identified the role of the State and its influence at the organisational level, which had been previously suggested in education literature (Ball, 1990).
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