<p><font face="Times New Roman"> <p align="left">The objective of this study was to determine the hydrosalinity fluxes associated with overland and subsurface (vadose zone) flow for different soils and land uses. For this purpose, the following data were collected during 2005 and 2006 in a typical small scale catchment located near the town of Riebeeck-Wes: weather data, hydrological and water quality measurements, soil water contents and chemistry, and vegetation growth. The area is characterized by a Mediterranean climate receiving winter rainfall of approximately 300 mm a <font face="Times New Roman">catchment is conservative, with Na</font> <font face="Times New Roman" size="1"><font face="Times New Roman" size="1">+ </font></font><font face="Times New Roman">and Cl</font><font face="Times New Roman" size="1"><font face="Times New Roman" size="1">- </font></font><font face="Times New Roman">being the dominant ions.</font></p> </font></p>

<p><font face="Times New Roman"> <p align="left">The objective of this study was to determine the hydrosalinity fluxes associated with overland and subsurface (vadose zone) flow for different soils and land uses. For this purpose, the following data were collected during 2005 and 2006 in a typical small scale catchment located near the town of Riebeeck-Wes: weather data, hydrological and water quality measurements, soil water contents and chemistry, and vegetation growth. The area is characterized by a Mediterranean climate receiving winter rainfall of approximately 300 mm a <font face="Times New Roman">catchment is conservative, with Na</font> <font face="Times New Roman" size="1"><font face="Times New Roman" size="1">+ </font></font><font face="Times New Roman">and Cl</font><font face="Times New Roman" size="1"><font face="Times New Roman" size="1">- </font></font><font face="Times New Roman">being the dominant ions.</font></p> </font></p>

Thesis (Ph.D.)--University of Western Australia, 2007.

Élimination de l'azote est obligatoire dans moderne usine de traitement des eaux usées (STEP) en raison de sa toxicité à la fois humaine et l'écosystème. Un niveau élevé d'azote peut provoquer une eutrophisation dans le système aquatique. Élimination de l'azote autotrophes qui combine nitritation partielle et Anammox est une technologie attrayante qui est approprié pour une grande force d'ammonium des eaux usées à faible teneur en carbone organique. Toutefois, le ralentissement de la croissance extrême des bactéries Anammox avec le temps de 9-13 jours doubler entrave la pleine application de l'échelle. L'objectif de cette recherche était d'étudier la faisabilité et la stratégie opérationnelle de l'enrichissement Anammox de boues conventionnelle aérobie (réacteur ASR), la dénitrification des boues (Réacteur DSR) et boue anaérobie (réacteur ANR) en utilisant réacteur biologique séquentiel (SBR). Anammox processus a été établi avec succès en DSR avec une élimination de l'azote total d'environ 80% sous le contrôle strict de l'oxygène au bout de 150 jours, ce qui est confirmé par la composition chimique de l'influent / effluents ainsi que l'analyse microbienne. Sous la même condition opérationnelle, ANR atteint seulement 20-30% d'élimination de l'azote total. Avec un temps plus court de rétention hydraulique (HRT) et de contrôle d'oxygène insuffisante, ASR a atteint 50-60% du total élimination de l'azote après 240 jours. Tous les réacteurs ont connu la fluctuation des performances au cours du processus d'enrichissement, qui est censé être la conséquence de facteurs inhibiteurs tels que l'oxygène dissous, sans nitrites et l'ammoniac libre ainsi que les bactéries coexistantes indésirables qui sont en concurrence pour le même substrat. L'électrophorèse sur gel de gradient dénaturant (DGGE) bande à partir des échantillons d'ADN amplifiés extraites ASR lors de l'étape d'enrichissement différente montre une nette évolution de la composition microbienne. Substances polymères extracellulaires (EPS) de différents biomasse Anammox ont été extraites et caractérisé par analyse quantitative et qualitative pour enquêter sur sa corrélation avec le processus d'enrichissement dans un bioréacteur de l'échelle du laboratoire. Une diminution de la protéine au polysaccharide (PN / PS) rapport et une augmentation du rendement total d'extraction EPS ont été observés au cours du processus d'enrichissement. La matrice à trois dimensions excitation d'émission (3D-EEM) a montré un endroit similaire des pics de fluorescence pour tous les échantillons tandis que les échantillons avec des bactéries Anammox possèdent deux pics distincts dans le bas de gamme d'onde d'excitation. Pics multiples excitation peuvent se produire comme en témoigne la fluorescence identique chromatogramme après chromatographie d'exclusion de taille (SEC) à séparation d'excitation / émission de 221/350 nm et 280/330 nm. Rayons ultraviolets (UV) absorbance à 210 nm a été enregistrée en même temps que la détection de fluorescence à une excitation / émission 222/300 nm de longueur d'onde, 221/350 nm et 280/330 nm après séparées par SEC. Avec l'enrichissement de bactéries Anammox, chromatogramme UV montré une augmentation en intensité et en nombre de pics, alors que chromatogrammes fluorescence ont montré nombre maximal similaire et seulement augmentent en intensité. Une augmentation de l'hydrophobie a été observée au cours du procédé d'enrichissement. Les résultats de cette étude sont attendus pour étendre la connaissance de l'évolution du processus d'enrichissement Anammox EPS ainsi que de fournir nouvelle approche pour la caractérisation des EPS extraites de Anammox boues / Removal of nitrogen is mandatory in modern wastewater treatment plant (WWTP) due to its toxicity to both human and the ecosystem. A high level of nitrogen may cause eutrophication in aquatic system. Autotrophic nitrogen removal which combines partial nitritation and Anammox is an attractive technology which is suitable for high Ammonium strength wastewater with low organic carbon content. However the extreme slow growth of the Anammox bacteria with doubling time of 9-13 days hinders its wide full scale application. The aim of this research was to investigate the feasibility and operational strategy of Anammox enrichment from conventional aerobic sludge (Reactor ASR), denitrification sludge (Reactor DSR) and anaerobic sludge (Reactor ANR) using sequencing batch reactor (SBR). Anammox process was successfully established in DSR with a total nitrogen removal of approximately 80% under strict oxygen control after 150 days which is confirmed by chemical composition of the influent/effluent as well as microbial analysis. Under the same operational condition, ANR reached only 20-30% total nitrogen removal. With a shorter hydraulic retention time (HRT) and insufficient oxygen control, ASR reached 50-60% total nitrogen removal after 240 days. All the reactors experienced fluctuating performances during the enrichment process, which is believed to be the consequence of inhibitory factors such as dissolved oxygen, free nitrite and free ammonia as well as undesirable coexisting bacteria which compete for the same substrate. The denaturing gradient gel electrophoresis (DGGE) band from the amplified DNA samples extracted from ASR during different enrichment stage shows a clear evolution of the microbial composition. Extracellular polymeric substances (EPS) from different Anammox biomass have been extracted and characterized by quantitative and qualitative analysis to investigate its correlation with the enrichment process in a lab scale bioreactor. A decrease of protein to polysaccharide (PN/PS) ratio and an increase in total EPS extraction yield were observed during the enrichment process. The three dimensional excitation emission matrix (3D-EEM) showed similar location of the fluorescence peaks for all samples while samples with Anammox bacteria possess two distinct peaks in the low excitation wavelength range. Multi-excitation peaks may occur as evidenced by the identical fluorescence chromatogram after size exclusion chromatography (SEC) separation at excitation/emission 221/350 nm and 280/330 nm. Ultraviolet (UV) absorbance at 210 nm was recorded simultaneously with fluorescence detection at excitation/emission wavelength 222/300 nm, 221/350 nm and 280/330 nm after separated by SEC. With the enrichment of Anammox bacteria, UV chromatogram showed increase in both intensity and number of peaks, whereas fluorescence chromatograms showed similar peak number and only increase in intensity. An increase of hydrophobicity was observed during the enrichment process. The results of this study are expected to extend the knowledge of EPS evolution of Anammox enrichment process as well as providing novel approach for the characterization of EPS extracted from Anammox sludge

>Magister Scientiae - MSc / The objective of this study was to determine the hydrosalinity fluxes associated with overland and subsurface (vadose zone) flow for different soils and land uses. For this purpose, the following data were collected during 2005 and 2006 in a typical small scale catchment located near the town of Riebeeck-Wes: weather data, hydrological and water quality measurements, soil water contents and chemistry, and vegetation growth. The area is characterized by a Mediterranean climate receiving winter rainfall of approximately 300 mm a catchment is conservative, with Na + and Cl- being the dominant ions.

The locomotor responses of juvenile and adult sockeye salmon (Oncorhynchus nerka) to concurrent changes in temperature and salinity were examined in a controlled laboratory setting. I hoped to better understand how these environmental factors influence the coastal movements of migrating salmon. Juvenile sockeye were captured during the downstream migration from Great Central Lake on Vancouver Island, British Columbia, Canada. The fish were acclimated for 1 wk at 10°C, 20 ppt, and then tested in annular activity tanks. Spontaneous locomotor movements were recorded during concomitant changes in temperature and salinity using infra-red photometry. Raising the water temperature by 4°C in 1 h caused a dramatic increase in locomotor activity. Decreasing temperature by 4°C or varying salinity by 10 ppt from the control levels did not influence routine swimming speed and there was no interaction between factors. Adult sockeye homing to the Fraser River, British Columbia, Canada were captured along the nearshore migration route in two oceanographically distinct regions. Three groups of fish were collected from the cold, saline waters of Queen Charlotte Strait, near the northern end of Vancouver Island. Two groups of sockeye were captured within 60 km of the Fraser River in the warmer, less saline waters of the Strait of Georgia. The adults were acclimated 2-5 days at 12°C, 30 ppt and locomotor activity was tested in annular activity tanks. Routine swimming speed and turning rate rose when the water temperature was raised by 4°C in 2 h, however, locomotor activity was not influenced by decreasing temperature. In addition, decreasing salinity by 10 ppt in 2 h had no effect on swimming activity of adult sockeye and there was no interaction between the two factors. Fish taken from the Strait of Georgia generally showed a less dramatic response to increasing temperature than adults captured in Queen Charlotte Strait. Results indicate that warm coastal temperatures may influence the nearshore migration of both juvenile and adult sockeye salmon. / Science, Faculty of / Zoology, Department of / Graduate

A study was conducted to determine the effects of incubation salinity and temperature . and post-hatching temperature on salinity tolerance of Pacific herring (Clupea pallasi Valenciennes) larvae. Calorimetry experiments were also conducted on herring larvae that were incubated and reared in various combinations of salinity and temperature. In the salinity tolerance test, herring eggs were artificially fertilized in three salinities (13, 21 and 29°/ooS) at 6°C. Newly fertilized eggs were incubated in the same salinities as those in which they were fertilized at two levels of incubation temperature (6 and 12°C), making six incubation groups. During the peak of the hatching period, groups of larvae from each incubation group were exposed to a series of test salinities, ranging from 20 to 55°/ooS at three levels of post-hatching temperatures (6, 9 and 12°C). Salinity tolerance was measured by determining the mortality of larvae occurring in each test salinity over a period of 72 hours. Two approaches were employed: 1) time-mortality, and 2) dosage-mortality. The former provided estimates of the effective time to 50% mortality (ET₅₀), the latter, the effective dosage (salinity) to 50% mortality (ED₅₀). The ET₅₀ or ED₅₀ values were used as bases for comparison of the responses of larvae to incubation temperature and salinity, and post-hatching temperature. The results indicate that both incubation salinity and temperature exert a significant influence on the salinity tolerance of larvae. Eggs incubated in the highest salinity (29°/ooS) and lower temperature (6°C) produced larvae most tolerant to higher post-hatching salinities. Post-hatching temperature also showed a possible influence, although the trends seen were not statistically significant. Salinity tolerance of larvae hatching from the 6°C incubation temperature appeared to be maximized at post-hatching temperatures between 6 and 9°C; whereas, those larvae from the 12°C incubation temperature showed maximum salinity tolerance at 9 to 12°C post-hatching temperatures. The response. of. larvae to salinity may be a result of an irreversible non-genetic adaptation of the embryo to salinity and temperature during incubation. In the calorimetry experiments, samples of herring larvae were combusted in a microbomb calorimeter to determine caloric values. These larvae were hatched and reared in the same six combinations of incubation salinities and temperatures as those used in the main experiment. Larvae were sampled at day 0 (peak of hatching), 3, 6 and 9. Standard lengths, dry weights, ash-free dry weights and ash content of the larval samples were also taken. There was a considerable variability in the data for calorimetry of the herring larva. In general, larvae from all treatments, at hatching, averaged 6,586 cal/g ash-free dry weight and had a mean ash value of 8.25%, obtained by direct ashing. Mean standard length of larvae at the peak of hatching (day 0) ranged from 7.67 mm (12°C, 29°/ooS) to 9.93 mm (6°C, 13°/ooS). There was a trend towards larger larvae (greater standard length) at lower temperatures in lower salinities in all ages tested. Data on dry weights show a linear decrease in larval (body and yolk) weight from day 0 to day 9. Mean dry weight of larva at the peak of hatching ranged from 0.142 mg (6°C, 13°/OOS) to 0.162 mg (12°C, 21°/ooS; 12°C, 29°/ooS). At day 0, the largest larvae (in terms of dry weight) were found at higher temperatures in higher salinities, while at day 9 (past yolk-sac stage), the largest larvae were found at lower temperatures in lower salinities. The same trend was observed in terms of ash-free dry weight. / Science, Faculty of / Zoology, Department of / Graduate

Two aspects of salinity in arid land were investigated as part of the present dissertation: the first was the potential re-use of industrially generated brine for irrigating landscape plants, and the second was the ecological restoration of saline farmland. The following is a summary of the most important points. With water conservation efforts accelerating in arid environments, industrial wastewater is considered a candidate for re-use. We investigated the use of high EC (electrical conductivity) cooling-tower water to irrigate nine common landscape plants in an urban environment. Each plant (replicated in a block design) was irrigated according to water demand determined by the soil moisture deficit, with one of three water treatments: blowdown water (3.65 dS m⁻¹), well water (0.52 dS m⁻¹) and a 1:1 blend (2.09 dS m⁻¹). Results indicate the salinity of the irrigation water did not have a significant effect (P>0.05) on growth or water use but, soil salinities were higher in basins irrigated with blowdown water compared to those irrigated with well water. The overall feasibility of reusing industrial brines to irrigate urban landscapes is discussed in light of the results. Restoring abandoned arid farmland can be challenging because topographic, geomorphic and hydrologic features have been degraded and cannot support a diverse native plant community. Typical amelioration practices depend upon good quality water to restore the soil’s physiochemical properties, however the long-term availability of any water is rare. A mitigation banking project to return 432 hectares of farmland to an open-space designation involved the collaboration of scientists, landscape architects and engineers to achieve five main goals: water management, erosion control, decreasing soil salinity, and increasing species diversity and vegetation cover. Two strategies evolved in the planning process that work in tandem to achieve these goals: a water management system that redirects storm water and run-off to discrete areas of the site for subsurface storage as plant-available water, and the introduction of a diverse mix of native plants. Field trials tested the strategies and also investigated different soil surface treatments, seeding methods and irrigation regimes against the germination and establishment of a customized native seed mix. Results from vegetation data indicate a combination of soil ripping and imprinting leads to the highest germination and establishment rates and drip irrigation helped establish transplanted seedlings. The project was designed so the longterm outcome does not depend on continual inputs and maintenance.

Salt-affected soils have undermined the effectiveness of agricultural development of considerable areas of the world, especially in the arid and semi-arid regions. This research is set out for the direct measurement of salt-affected soil. Two experiments were conducted to study the influence of different salt types and concentrations on spectral reflectance of soil. In the first experiment, five different salts (Na₂SO₄, NaHCO₃, CaCO₃, CaCl₂ and NaCl) were mixed individually with Gila soil at 0.51, 1.51 and 3.0% by weight. The second experiment was conducted to examine the spectral response of sodium sulfate and sodium bicarbonate (individually and in combination) in Gila soil at 3.0 and 6.0% by weight. Reflectance measurements were made over all soil treatments under different moisture conditions. Upon drying (24-hour after wetting), different salt types and concentrations showed different spectral response. The chemical analysis of soil samples have indicated some important relationships which influenced, directly and indirectly, the spectral reflectance of soil surfaces.

No description available.