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Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 39-44). Also available on the World Wide Web.

This study aims to understand tourism carrying capacities of diving sites in Hong Kong and Malaysia. Specifically, ecological, psychological and social carrying capacities were assessed. Methodology involved photo quadrat transect survey, questionnaire survey and visual experiment survey. Over a period of two calendar years (2013 and 2014), 13, 12 and 9 photo quadrat transect surveys were conducted in Sharp Island, Tsim Chau and Mabul Island (Ray Point and Eel Garden) respectively to provide data for ecological carrying capacity assessment. In addition, 455 and 342 questionnaires were collected in Hong Kong and Mabul Island respectively to assess divers' satisfaction with diving attributes of the respective dive sites. Regarding social carrying capacity assessment, 247 and 158 visual experiment questionnaires were collected to assess crowding as perceived by divers in the two sites.;The ecological carrying capacity of Sharp Island lies between 172 and (less than) 825 divers every quarter in the absence of better solutions. At Tsim Chau, diving activity is not the most important factor in influencing the coverage of sea anemone. In addition, the use of additional (subjective) data was necessary to define the ecological carrying capacity of Tsim Chau and possibly Sharp Island. In Mabul Island, the results show that the ecological carrying capacity is about 16800-17200 divers per year at Ray Point and about 15600-16800 divers per year at Eel Garden. Based on the findings, it is likely that the usage of the diving sites on Sharp Island, Ray Point and Eel Garden have already exceeded the social carrying capacity. Regarding the psychological carrying capacity, this study found that the most important factor that influences divers' willingness to return to Hong Kong diving sites is "the quality of corals". In Mabul Island, the most important factor is "the value for money of Mabul diving". However, no studied diving sites have exceeded their psychological carrying capacities. Regarding the social carrying capacity, on both Hong Kong and Mabul Island diving sites, the "number of divers" was found to be the most influential factor for divers' perceived crowding. In Hong Kong, divers' begin to feel unacceptably crowded if 78̃ divers are visible to them at one time whereas in Mabul Island, divers would start to feel unacceptably crowded if 8 to 9 divers were visible to them at one time. Based on this, it is likely that the usage of both Hong Kong and Mabul Island diving sites have already exceeded the social carrying capacity.;With the increasing popularity of diving in recent years, divers and diving trips operators around the world need to be aware of divers' impact on coral reef, divers' satisfaction and underwater crowding problem. Finally, a series of management and policy measures to minimise the impact of diving activity on coral, improve divers' satisfaction and mitigate divers' crowding perception in underwater environment are proposed for sustainable use of diving sites in Hong Kong and Mabul Island.

Initial experiments evaluated the impact of hematocrit on a bird’s ability to adapt to stress and what physiological mechanisms occurred to maintain oxygen carrying capacity (OCC). A final experiment was conducted to obtain proteomic evaluation of protein expression in monocytes of unstressed broilers. In initial experiments, ACTH treatment was applied to hematocrit separated broilers. Experiments evaluated effects of ACTH on broilers with low (19 to 22%, Experiment 1; 18-21%, Experiment 3), high (25 to 28%, Experiment 1; 24 to 27%, Experiment 3) or non-selected hematocrit levels (Experiment 2 and 3). After 4 d of ACTH, all treated birds had significantly increased (P < 0.1) pCO2, HCO3-, and corticosterone levels, indicating as stress raises pCO2, HCO3- must rise to maintain acid base balance. Birds not selected for hematocrit had significant drops in pO2 when given ACTH. Broilers compensate for low OCC through release of red blood cells from storage sites, indicated by decreases in organ hemoglobin and increases in hematocrit and blood hemoglobin when birds are given ACTH. Accelerated red blood cell formation does not appear to occur, because erythropoietin decreases following administration of ACTH to non-selected birds. ACTH induced stress, increased hemoglobin and hematocrit only in birds with low or non-selected hematocrit, suggesting high hematocrit birds prior to stress have an adaptive advantage during stress. Higher hematocrit prior to stress apparently provides ample OCC during stress. Unselected birds appear to require initiation of an inflammatory response to adapt to stress which can be noted by increases in total white blood cell count, monocytes, and heterophils and decreases in lymphocytes. High hematocrit birds appear less susceptible to stress effects by maintaining leukocytes at a constant level, while in non-selected birds lymphocyte percents drop. Proteomics was conducted on avian monocytes to reveal proteins related to immune functions, 3229 proteins were identified, with 46 involved in immune functions of professional antigen presenting cells. This protein data provides a means of comparing monocytes of stressed and unstressed animals in the future. In conclusion, evaluated hematocrit is advantageous in adaptation to stress through maintenance of high OCC, acid base balance and immune cells.

This thesis seeks to establish the levels of population densities, beyond which excessive pressure of population on land would occur in parts of Owerri Province, Nigeria. These Critical Population Densities are determined using Allan's Model. The results of an original field survey and questionnaire provided the information for calculating land requirement per head of the population, and for estimating the carrying-capacity of land. Certain normative hypotheses relating some variables in agricultural land use to elements of farm structure are tested. Other tests are also performed to determine the relative degree of importance of the variables associated with acreage per head cultivated in the province in 1971. / Thesis / Master of Arts (MA)

The Swedish government is planning to increase the maximum vehicle gross load regulations on parts of the national roads from the present 60 t, for the load carrying capacity class BK1, to 74 t, for the proposed new load carrying capacity class BK4. The initial implementation of the new load carrying capacity class for 74 t vehicles will only regard major highways and important roads, however, at a later stage the plan is to implement the new BK4 class on the full current BK1 road network. The biggest obstacle which arises when implementing these increased traffic loads is insufficient load carrying capacity for the bridges on the road network.   Thus, the objective of this thesis is to examine and analyze the effects of the increased traffic loads on Swedish road bridges. In order to identify the structural effects of the load increase, and draw general conclusions regarding the effects on the bridge network as a whole, a case study with load carrying capacity calculations is carried out on a two-span concrete slab fram bridge at a highway interchange in Värö in western Sweden. The bridge is classified as critical by Trafikverket. The load carrying capacity calculation is carried out using the Swedish standards, in which maximum load values for the axle load, A, and the bogie load, B, is calculated.   The load effects acting on the bridge are calculated using the finite element software BRIGADE/Standard, with input traffic A and B loads amounting to 12 t and 21 t respectively for the new BK4 class and to 12 t and 18 t respectively for class BK1. In addition to the load carrying capacity calculations with BK4 traffic loads, a comparison is carried out between the results obtained when using the axle- and bogie loads from the BK1 versus the BK4 load carrying capacity class in the load carrying capacity calculations.   The load carrying capacity calculations performed on the studied bridge shows that the capacity of the bridge, both in regards to moment and shear force, is insufficient to meet the new, increased, BK4 A/B – requirements. The critical A/B – values for the whole bridge are 17 t and 18 t respectively, to be compared with the required 12- and 21 t limit for the new BK4 load carrying capacity class, thus, making the load carrying capacity of the bridge inadequate. The critical A/B – values appear for the longitudinal shear force load case at the point where the shear force reinforcement over the column support ends. Moreover, the difference between the results obtained when using the BK1 versus the BK4 traffic loads in the calculations were found to be negligible.   Due to the differing properties and characteristics of each individual bridge on the Swedish road network it is difficult to make general statements regarding the effects of the increased traffic loads on the bridge network as a whole. Specific load carrying capacity calculations will need to be performed on each individual bridge in order to evaluate its capability to withstand the new increased BK4 traffic load. However, capacity calculations regarding the BK1 load carrying capacity class can, with sufficient accuracy, be used to evaluate the capability of a bridge to withstand the increased traffic loads in the BK4 load carrying capacity class, thus, making it easier to evaluate the strengthening needs for the bridge network as a whole. / Sveriges regering planerar en utökning av den maximalt tillåtna bruttovikten för fordon på delar av det allmänna vägnätet från den nuvarande begränsningen på 60 t, för bärighetsklass BK1, till 74 t, för den nya föreslagna bärighetsklassen BK4. I det första skedet kommer den nya bärighetsklassen, för fordon med bruttovikt upp till 74 t, bara att implementeras på stora motorvägar och andra ur transportsynpunkt viktiga vägar, men, i ett senare skede finns också planer på att implementera den nya bärighetsklassen, BK4, på hela det nuvarande BK1 vägnätet. Det största problemet som förväntas uppkomma under införandet av de nya, ökade, trafiklasterna är otillräcklig bärighet på vägnätets broar.   Således är målet med denna uppsats att undersöka och analysera effekterna av dessa ökade trafiklaster för broar på det Svenska vägnätet. För att identifiera effekterna, och dra generella slutsatser, gällande denna ökade trafiklast för broarna på det Svenska vägnätet i sin helhet kommer en fallstudie med bärighetsberäkningar utföras på en plattrambro vid trafikplats Värö - en bro som Trafikverket bedömer som kritisk. Bärighetsberäkningen utförs enligt svenska standarder, där maximala tillåtna värden på axellasten, A, och bogielasten, B, beräknas.   Lasteffekterna som verkar på bron beräknas med hjälp finita element programvaran BRIGADE/Standard med trafiklaster, A och B, som uppgår till 12  respektive 21 t för den nya BK4 bärighetsklassen och 12 respektive 18 t för bärighetsklass BK1. Som tillägg till bärighetsberäkningarna med BK4 laster utförs också en jämförelse av resultaten som uppkommer när axel- och bogielasterna från BK1 respektive BK4 används i beräkningarna.    Bärighetsberäkningarna på den studerade bron visar att brons kapacitet, både gällande moment och tvärkraft, är otillräcklig när den belastas med de ökade BK4 trafiklasterna. De kritiska A- och B- värdena för bron är 17 respektive 18 t, värden som skall jämföras med kraven på 12 respektive 21 t för den nya bärighetsklassen BK4 – därmed är brons bärighet otillräcklig. De kritiska A- och B-värdena för bron uppkommer för lastfallet med longitudinell tvärkraft vid punkten där tvärkraftsarmeringen över mittstödet slutar verka. Jämförelsen mellan beräkningsresultaten som uppkom med trafiklaster enligt BK1 respektive BK4 visade att skillnaden mellan beräkningsresultaten var försumbar.   På grund av de varierande egenskaperna hos varje enskild bro på det Svenska vägnätet är det svårt att dra generella slutsatser gällande effekterna av lastökningen för vägnätet som helhet. Specifika bärighetsberäkningar måste utföras på varje individuell bro för att kunna utvärdera dess kapacitet att klara av de nya, ökade, BK4 trafiklasterna. Emellertid kan bärighetsberäkningar som beträffar bärighetsklassen BK1, med tillräcklig tillförlitlighet, användas för att bedöma en bros möjlighet att motstå de ökade trafiklasterna i den nya bärighetsklassen BK4, vilket förenklar utvärderingen av vilka broar som kräver förstärkning.

<p>Livestock keeping has been the essential source of livelihood in Babati District for many hundreds of years. The traditional ecological knowledge about this semi-arid environment has influenced the general view on livestock management. This essay discusses the measures that are, or could be taken in Babati District to prevent overstocking and overgrazing in the woodlands. With the continuing population density increase also the livestock population grows. More houses and roads are built and the grazing lands diminish. To avoid overgrazing forest management programmes restrict grazing in forests. This additionally decreases availability of grazing land. My conclusion is that minimizing number of livestock is necessary to not exceed carrying capacity of pasture during drought. Hence this is not free from problems since it is traditionally rooted to have a large number of livestock as a buffer of energy and wealth. One solution for both how to prevent overstocking and how to survive with small number of livestock is to practise zero-grazing. Zero-grazing is to keep a small number of healthy big cattle e.g. exotic cows or crossbreeds in stables or tied up. However, when tying cattle on the spot the fact that cattle have four legs is disregarded.</p>

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Thesis advisor: Gail C. Kineke / Experiments were conducted in the Petitcodiac River in New Brunswick, Canada during June and August 2006 to study high-concentrations of suspended sediment in a turbulent system. This study will evaluate the conditions necessary for fluid mud formation by investigating 1) the suppression of turbulence at gradient Richardson numbers greater than 0.25; 2) a threshold condition for the amount of sediment a flow can maintain in a turbulent suspension; and 3) the influence of flocculation on vertical suspended-sediment transport. Direct measurements of salinity, temperature, current velocity, and suspended-sediment concentration were collected during accelerating and decelerating flows and when fluid mud formed. In June, current velocities were typically above 1 m s<super>-1</super> and suspended-sediment concentrations were generally less than 10 g l <super>-1</super>. In August, current velocities were typically less than 1.5 m s<super>-1</super>, suspended-sediment concentrations were greater than 10 g l <super>-1</super>, and a high-concentration bottom layer formed rapidly during decelerating flood currents. Gradient Richardson numbers for concentrations greater than 10 g l <super>-1</super> were generally greater than 0.25, suggesting strong density gradients have the ability to suppress turbulence. Results from the Petitcodiac suggest a carrying capacity threshold might exist, but is based on a critical gradient Richardson number between 1.0 and 2.0 rather than the previously accepted value of 0.25. Differences in the evolution of disaggregated grain size distributions for settling suspensions suggest flocculation plays an important role for fluid mud formation by enhancing settling of fine sediments. / Thesis (MS) — Boston College, 2009. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Geology and Geophysics.

As atividades recreativas em áreas naturais são apresentadas como uma ferramenta capaz de conciliar desenvolvimento e conservação. Entretanto, a falta de um planejamento que leve em consideração os fatores relacionados com sua sustentabilidade pode ocasionar graves impactos tanto ecológicos como econômicos e sociais. No Brasil, onde as discussões sobre o assunto são muito recentes, existe falta de informações sistematizadas sobre as verdadeiras repercussões do uso recreativo e sobre a recuperação dos ambientes. Além da própria complexidade do assunto, existe uma outra dificuldade em razão da bibliografia específica, dispersa e nem sempre de fácil acesso. No presente trabalho é feita, no primeiro capítulo, uma revisão bibliográfica sobre: a natureza dos impactos; os fatores relacionados a sua ocorrência e à capacidade de carga do ambiente; os métodos de avaliação de impacto mais usados; e a experiência brasileira. Esta revisão forneceu a base teórica necessária para a elaboração do estudo de caso, visando discutir a sustentabilidade ecológica das atividades recreativas. No segundo capítulo foi realizado um estudo na antiga Fazenda Santa Carlota (SP),área de elevado potencial turístico. Para tanto, elaborou-se um zoneamento ecológico, em ambiente de SIG, sintetizando as fragilidades e as oportunidades. Para o Mapa de Fragilidades foram utilizadas as informações abióticas (pedologia,declividade, geomorfologia e clima) e bióticas (vegetação e fauna) relacionadas com a capacidade de carga para recreação (CCR) do ambiente. Para o Mapa de Oportunidades, foi feito um levantamento preliminar dos atrativos potenciais para a área de estudo. O resultado é o Mapa de Zoneamento Ecológico que classifica a fazenda em cinco zonas: três zonas propostas para o desenvolvimento de atividades recreativas, com níveis diferentes de fragilidade e potencialidade; uma de uso especial, onde está o patrimônio histórico; e uma zona de recuperação. Foi estimada a CCR, adaptando o método de Cifuentes (1992), para cada uma das três zonas destinadas para o uso. Os valores obtidos representam os limites máximos de uso que devem ser permitidos de forma a evitar a degradação dos recursos naturais. Estes valores não são absolutos e incorporam conhecimento científico e juízos de valor. A utilização do SIG mostrou-se adequada para o objetivo de zoneamento ecológico para fins recreativos. O método de CCR mostrou-se flexível e rápido. Porém, a CCR foi superestimada devido aos fatores importantes não incorporados por falta de dados específicos e à escala de trabalho. / Recreational activities in wildland areas are being considered a way to achieve development and protect the environment. However, without a planning program that considers the factors related to their sustainability, they can cause serious ecological, economic and social impacts. In Brazil, in spite of the recent concerns about recreational problems, there is a lack of systematic information about actual consequences of the recreational use and environmental restoration. It is very difficult to deal with the recreational sustainability, due to its complexity and to a dispersed and inaccessible specific bibliography. The first chapter of this work is a bibliography revision on: the nature of the impacts; the factors related to their occurrence and the environmental carrying capacity; the most useful methods of impact evaluation; and the Brazilian experiences. This revision supplied the theoretical base necessary for the elaboration of a study case that intended to discuss the ecological sustainability of recreational activities. The second chapter is a study about Fazenda Santa Carlota (SP), an area with a high touristic potential. A GIS was used to elaborate an ecological zoning, synthecizing fragilities and opportunities. Abiotic (pedology, slope, geomorfology and climate) and biotics informations (vegetation and wildlife) related with the recreational carrying capacity (RCC) have been used to elaborate the Map of Fragilities. For the Map of Opportunities, a preliminary survey of the attractive potentials for the study area was made. The result is the Map of Ecological Zoning that classifies the area in five zones: three zones that permit for the development of recreational activities, with different levels of fragility and potentiality; one zone of special use, where there is a historic site; and a restoration zone. The RCC was estimate, for each of the three recreational zones, using the Cifuentes method (1992). The values obtained represent the limits of acceptable change that could be allowed to prevent the degradation of the natural resources. These values are not absolute and involve scientific and judgmental considerations. The use of GIS revealed to be adequate for the objective of ecological zoning for recreationals objectives. The RCC method revealed to be flexible and fast. However, due to important factors not considered because of lack of specific data and due to the working scale, it overestimates the RCC.