The ecological importance of drifting will depend on the abundance of drifting algae and whether it is reproductively viable. However, the ability of adult plants to successfully disperse long-distances by drifting is largely unknown, particularly for fucoids. The abundance, species composition, and reproductive status of drifting algae was examined by transect surveys around Kaikoura and Banks Peninsula. Abundance and species composition varied between sites, but all drifting algae that were in reproductive season, and had reproductive structures intact, were reproductively active. The reproductive longevity and viability of drifting and beach-cast Hormosira banksii, Durvillaea antarctica and Cytophora torulosa was compared with attached populations. Drifting algae remained reproductively viable, and fecundity did not differ from that of attached algae. Viable propagules were released from drifting algae for the duration of the experiments (H. banksii 57 days, D. antarctica 62 days, and C. torulosa 43 days). In contrast, beach-cast algae ceased to release propagules after 14 days. Dispersal by drifting relies on offshore transport after detachment. To determine the influence of wind and tidal currents on the nearshore transport of drifting algae, tagged H. banksii, D. antarctica, C. torulosa and GPS-tracked drifters were released from shore. Drifters generally moved in the direction of the prevailing wind, but some influence of tidal direction and bathymetry was detected. Offshore winds and outgoing tides were favourable for the offshore transport of surface drifting algae. Following dispersal and arrival at new locations, the distance between gametes may be important in determining the fertilisation success of dioecious species. Experiments testing the fertilisation success of H. banksii and D. antarctica, over increasing distances, showed that fertilisation success decreased with increasing distance between male and female gametes. Despite this, eggs were fertilised when male and female gametes were up to 2m apart, and sperm remained viable for 2 hours.

An alum coagulation treatment facility employing mixing, flocculating, and settling units, designed by criteria commonly used in the design of water treatment facilities, was operated to determine whether or not it could effectively remove algae and other suspended matter from raw sewage stabilization lagoon effluent. Algal sludge produced by the treatment facility was investigated: (1) to evaluate its potential as a soil conditioner; (2) to determine whether a stabilization lagoon could be used for algal sludge disposal; and (3) to determine whether or not sludge recirculation would reflect a chemical savings. The experimental lagoons and treatment facility, owned by Sanitary District No. 1 of Pima County, Arizona, were located near Tucson, Arizona. It was found, in a field study, that mixing, flocculating, and settling units commonly used for water treatment were efficient in clarifying lagoon effluent and produced a water with the appearance of tap water. Active photosynthesizing algae, producing high oxygen concentrations in lagoon effluent, caused flotation of alum coagulated algal sludge; however, by selecting lagoon effluent low in dissolved oxygen content, algal sludge flotation in the treatment facility was prevented. Algal sludge with Less than one percent total solids was readily dewatered in three days by sand bed drying. Resuspension of air dried algal sludge resulted in a maximum moisture uptake of 50 percent of the final wet weight. Dry algal sludge contained 47 to 61 percent volatile solids, 1.6 to 5.2 percent total phosphorus, and 3.6 to 4.9 percent organic nitrogen. No significant amount of ammonia nitrogen or nitrite-nitrate nitrogen was present in the sludge. The composition and characteristics of dry algal sludge indicate applicability as an aid to soil conditioning. For three months the characteristics of a lagoon used for algal sludge disposal were compared with a control lagoon operated in parallel; it was found that the returned algal sludge was not detrimental to the stabilization process. Acid treated and non-acid treated algal sludge produced from completely treated lagoon effluent had a clarifying value when reused with alum to coagulate effluent, but neither acid treated nor nonacid treated sludge produced from partly treated effluent caused additional clarification when returned with the same coagulant dose that initially produced the sludge. None of the different types of return sludge investigated had a clarifying value when returned under operating conditions necessary to obtain a coagulant savings.

This thesis consists of work conducted in two separate studies, evaluating the performance of passive systems for treating wastewater effluents. The first study involved the characterization of three wastewater stabilization ponds (WSPs) providing secondary and tertiary treatment for municipal wastewater at a facility in Amherstview, Ontario, Canada. Since 2003, the WSPs have experienced excessive algae growth and high pH levels during the summer months. A full range of parameters consisting of: pH, chlorophyll-a (chl-a), dissolved oxygen (DO), temperature, alkalinity, oxidation-reduction potential (ORP), conductivity, nutrient species, and organic matter measures; were monitored for the system and the chemical dynamics in the three WSPs were assessed through multivariate statistical analysis. Supplementary continuous monitoring of pH, chl-a, and DO was performed to identify time-series dependencies. The analyses showed strong correlations between chl-a and sunlight, temperature, organic matter, and nutrients, and strong time dependent correlations between chl-a and DO and between chl-a and pH. Additionally, algae samples were collected and analyzed using metagenomics methods to determine the distribution and speciation of algae growth in the WSPs. A strong shift from the dominance of a major class of green algae, chlorophyceae, in the first WSP, to the dominance of land plants, embryophyta – including aquatic macrophytes – in the third WSP, was observed and corresponded to field observations during the study period. The second study involved the evaluation of the performance and chemical dynamics of a hybrid-passive system treating leachate from a municipal solid waste (MSW) landfill in North Bay, Ontario, Canada. Over a three year period, monitoring of a full range of parameters consisting of: pH, DO, temperature, alkalinity, ORP, conductivity, sulfate, chloride, phenols, solids fractions, nutrient species, organic matter measures, and metals; was conducted bi-weekly and the dataset was analyzed with time series and multivariate statistical techniques. Regression analyses identified 8 parameters that were most frequently retained for modelling the five criteria parameters (alkalinity, ammonia, chemical oxygen demand, iron, and heavy metals), on a statistically significant level (p < 0.05): conductivity, DO, nitrite, organic nitrogen, ORP, pH, sulfate, and total volatile solids. / Thesis (Master, Civil Engineering) -- Queen's University, 2013-10-27 05:29:20.564

Kelpak®, a seaweed concentrate (SWC) prepared from the brown seaweed Ecklonia maxima (Osbeck) Papenfuss, improves overall plant mass and fruit yield in a variety of crops. The main active principals isolated from Kelpak® are cytokinins and auxins. Although these compounds are partly responsible for the growth promoting effect observed with Kelpak® application, they do not fully account for the complete effect of Kelpak® treatment. For this reason the focus has turned to polyamines (PAs) which are found in all cells of plants, animals and microorganisms, including eukaryotic algae. Polyamines also have growth promoting effects in plants. A study was carried out to investigate the PA levels in E. maxima and Kelpak® through a biennial cycle and to investigate if the PAs present in Kelpak® may have an effect on root growth, alleviating nutrient deficiency and the transport and accumulation of PAs in plants. To determine the amount of PA in the stipes, fronds and SWC prepared from E. maxima, samples were collected monthly over a two-year period (June 2009-June 2011). Extracts were benzoylated and quantified using a Varian HPLC. Putrescine concentrations ranged from 15.98-54.46 μg.g⁻¹, 6.01-40.46 μg.g⁻¹ and 50.66-220.49 μg.g⁻¹ DW in the stipe, fronds and SWC, respectively. Spermine concentrations ranged from 1.02-35.44 μg.g⁻¹, 1.05-26.92 μg.g⁻¹ and 7.28-118.52 μg.g⁻¹ DW in the stipe, fronds and SWC, respectively. Spermidine concentrations fell below the detection threshold. This is the first report of PAs being detected in a SWC. The seasonal pattern established for the stipe, frond and SWC followed the same trend over a biennial cycle. Polyamines accumulated in the seaweed tissue during periods of active growth and as a stress response elicited by rough wave action. This PA trend was similar to the cytokinin trend reported by MOONEY and VAN STADEN (1984b) for Sargassum heterophyllum which suggests that PAs play an important role in the hormone cascade during active growth. Routine monthly screening of Kelpak® carried out in the Research Centre for Plant Growth and Development indicated that Kelpak® consistently resulted in more rooting in the mung bean bioassay than the IBA control. The potential root promoting effect of PAs were investigated. Individually applied PAs did not increase rooting in the mung bean bioassay, but a synergistic relationship was observed between Put (10⁻³ M) and IBA (10⁻⁴ M). When applied together, rooting increased significantly above Put (10⁻³ M) and IBA (10⁻⁴ M) applied separately. The Put-auxin combination produced a similar number of roots to those treated with Kelpak®. It is possible that the PAs present in Kelpak® have a synergistic effect with auxins present in Kelpak® to promote root development and growth. Several physiological effects of Kelpak® and PAs on plant growth were investigated in a series of pot trials. Kelpak® significantly improved the growth of P- and K-deficient okra seedlings and masked the detrimental effects exerted by P- and K-deficiency. The application of PAs (10⁻⁴ M) significantly improved the seedling vigour index (SVI) of okra seedlings subjected to N-deficiency. The statistical difference was attributed to the N-containing growth regulators and polyamines being degraded and metabolized by the okra seedlings. Polyamine application did not alleviate P- and K-deficiency but increased root growth significantly in seedlings receiving an adequate supply of nutrients. It is likely that the additional PAs supported auxin-mediated root growth. A pot trial with okra plants was conducted to establish if the PAs in Kelpak®, applied as a soil drench or foliar application, are absorbed and translocated in a plant. Plants were also treated with Put, Spm, Spd to establish if PAs can be absorbed and translocated. Once the fruit had matured, plants were harvested and the endogenous PA content quantified by HPLC in the roots, stems and fruits. Applying PAs as a soil drench was not as effective as a foliar spray at increasing the PA content in the different plant parts. Kelpak® treatment (0.4%) did not contribute more PAs in any plant part. Spermidine concentrations were higher, in the various plant parts, than Put or Spm, irrespective of the mode of application. The application of Put, Spd and Spm increased Spd concentrations in the roots. Considering that Spd is the main PA produced in the roots and that exogenously applied PAs are readily converted to Spd, it seems evident that Spd is the preferred PA for long-distance transport in plants. The cytokinins and auxins in Kelpak® play an important role in stimulating growth in plants. It is, however, the totality of different compounds in Kelpak® that gives it its unique growth stimulating ability. Polyamines, occurring within the seaweed contribute to this activity, having an active role in root production and thus increased plant growth. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.

Biosorption is a property of certain type of inactive, microbial biomass to bind and concentrate heavy metals from even very dilute aqueous solutions. Biomass exhibits this property, acting just as a chemical substance, as an ion exchanger of biological origin. It is particularly the cell wall structure of certain algae that is found responsible for this phenomenon. In these experiments, the rate and extent for removal of copper is subjected to parameters such as pH, initial metal concentration, biosorbent size, contact time, temperature and the ability of the biomass to be regenerated in sorption-desorption experiments. The metal adsorption was found to be rapid within 25 minutes. The maximum copper uptake of 30 mg of copper / g of biomass has been observed, in the following conditions: 100 mg / L, 0.1 g of biomass, pH 4 and at temperature of 25°C. From this study, it was found that copper uptake is increasing with increase in pH, with optimum being pH 4. Copper uptake increases substantially from 0 to 25 minutes. Metal biosorption behaviour of raw seaweed Sargassum in six consecutive sorptiondesorption cycles were also investigated in a packed-bed column, during a continuous removal of copper from a 35 mg/l aqueous solution at pH 4. The sorption and desorption was carried out for an average of 85 and 15 hours, respectively, representing more than 40 days of continuous use of the biosorbent. The weight loss ofbiomass after this time was 13.5%. The column service time decreased from 25 hrs in the first cycle to 10 hrs for the last cycle. / Thesis (M.Sc.)-University of KwaZulu-Natal, 2005.

This thesis covers work carried out on algae bioreactors as a tertiary treatment process for wastewater treatment. The process was primarily assessed by the removal of Phosphorus and Nitrogen as an alternative to chemical and bacterial removal. Algal bioreactors would have the added advantage of carbon sequestration and a by-product in the energy rich algal biomass that should be exploited in the existing AD capacity. Laboratory scale bioreactors were run (4.5-30L) using the secondary treated final effluent from the local Loughborough sewage works. In a preliminary series of experiments several different bioreactor designs were tested. These included both batch feed and continuous flow feed configurations. The bioreactors were all agitated to keep the algal cells in suspension. The results demonstrated that the most effective and easy to operate was the batch feed process with the algal biomass by-product harvested by simple gravitational settling. Experiments also compared an artificial light source with natural light in outdoor experiments. Outdoor summer light produced greater growth rates but growth could not be sustained in natural UK winter light. Light intensity is proportional to productivity and algae require a minimum of around 97W/m2 to grow, an overcast winter day (the worst case scenario) was typically around 78W/m2, however this was only available for a few hours per day during Nov-Jan. The process would be better suited to areas of the world that receive year round sunlight. It was shown that phosphorus could be totally removed from wastewater by the algae in less than 24 hours depending on other operating variables. With optimisation and addition of more carbon, a HRT of 10-12 hours was predicted to achieve the EU WFD / UWWTD standard. It was further predicted that the process could be economically and sustainably more attractive than the alternatives for small to medium sized works. Biomass 3 concentrations of between 1-2g/L were found to best achieve these removals and produce the fastest average growth rates of between 125-150mg/L/d. The uptake rates of phosphorus and nitrogen were shown to be dependent on the type of algae present in the bioreactor. Nitrogen removal was shown to be less effective when using filamentous bluegreen algae whilst phosphorus removal was almost completely stopped compared to unicellular green algae that achieved a nitrogen uptake of 5.3mg/L/d and phosphorus uptake of 8mg/L/d. Soluble concentrations of Fe, Ni and Zn were also reduced by 60% in the standard 10 hours HRT. The predominant algae were shown to depend largely on these concentrations of phosphorus and nitrogen, and the strain most suited to that specific nutrient or temperature environment dominated. Nutrient uptake rates were linked to algal growth rates which correlated with the availability of Carbon as CO2. CO2 was shown to be the limiting factor for growth; becoming exhausted within 10 hours and causing the pH to rise to above 10.5. The literature showed this was a common result and the use of CO2 sparging would more than double performance making this process a good candidate for waste CO2 sequestration. Heat generated from combustion or generators with exhaust CO2 would also be ideal to maintain a year round constant temperature of between 20-25°C within the bioreactors. A number of possible uses for the algal biomass generated were examined but currently the most feasible option is wet anaerobic co-digestion. Further economic analysis was recommended on the balance between land area and complementary biomass generation for AD. It was also suggested given the interest as algae as a future fuel source, the process could also be adapted for large scale treatment and algal biomass production in areas of the world where land was available.

Les rejets d'effluents liquides des Centres Nucléaires de Production d'Electricité (CNPE) sont constitués d'un mélange de substances stables et radioactives. L'exposition d'organismes à des substances en mélange peut faire l'objet d'interactions diverses, conduisant à une augmentation ou à une diminution des effets observés. Afin d'identifier de possibles interactions dans le cas de mélanges de substances caractéristiques (en termes de toxicité et de quantité) des rejets de CNPE, l'effet d'un mélange binaire composé de cuivre et d'HTO a été étudié sur le modèle d'algue unicellulaire Chlamydomonas reinhardtii. Dans un premier temps, la toxicité de l'HTO a été analysée. L'HTO s'est révélée être peu toxique envers notre modèle biologique. L'effet le plus sensible et le plus précoce est une augmentation du stress oxydant (dès 40 kBq mL-1 - 0.13 µGy h-1). Lors de l'exposition des cellules algales au mélange HTO/Cu, une interaction a été révélée au niveau du stress oxydant cellulaire, celui-ci étant supérieur à une simple addition de l'effet des deux substances. Cette interaction peut s'expliquer par une augmentation de l'internalisation du cuivre en présence d'HTO, mais aussi potentiellement par des interactions toxiques directes (notamment sur les processus de régulation du stress oxydatif). En conclusion, il a été démontré que l'effet de substances stables et radioactives en mélange peut être supérieur à l'addition. Bien qu'étant uniquement représentative du mélange binaire HTO/Cu, cette étude montre néanmoins de potentielles interactions entre substances stables et radioactives, à considérer lors de l'évaluation des risques écologiques relatifs aux rejets de CNPE. / Liquid releases by Nuclear Power Plants (NPP) are composed of a mixture of radioactive and non-radioactive substances. When organisms are exposed to mixtures of contaminants the resultant toxicity can be enhanced, or reduced, due to interactions. In order to identify potential interactions between substances released by NPP, two substances representative of such effluents (in term of toxicity and of quantity) were selected for studies: Tritiated water (HTO) and copper (Cu). Effects of this binary mixture were studied on the unicellular green algae Chlamydomonas reinhardtii. HTO, when examined along, was not very toxic to C. reinhardtii. The most sensitive and early effect of HTO was an increase in oxidative stress at concentrations of 40 kBq mL-1 (0.13 µGy h-1). Algae exposure to the binary mixture HTO/Cu induced interactive effects on oxidative stress. Reactive Oxygen Species production was higher from exposure to the mixture of contaminants than the addition of the effect from each substance individually. This interaction was explained by an enhanced copper uptake by the alge when in the presence of HTO. The observed supra-additive effect could also be due to direct toxic interactions, especially on the antioxidant system. To conclude, this study showed that the effects of a mixture of radioactive and non-radioactive substances can be greater than what would be predicted based on mere addition of individual effects. Even thought this binary mixture is just a small part of NPP effluents, the study showed that potential interactions should be considered when determining ecological risks too aquatic ecosystems from NPP effluents.

Research using microalgae Chlorella vulgaris was conducted in order to determine the maximum CO2 concentration under which algae can grow, within the emission range from oil and natural gas burning plants (0-20%). After choosing the optimal CO2 percentage, pH and alkalinity were determined; and finally, an electrochemical (EC) batch reactor connected to DC current was applied to achieve algae cell annihilation, and therefore, facilitate anaerobic digestion, methane production and energy recovery. It was determined that algae can grow under 20% CO2, being 15% CO2 the most effective (pH of 6.64 and alkalinity of 617.5 mg/L CaCO3). Electroporation using an electrochemical batch reactor is effective in breaking cells membranes, which simplifies anaerobic digestion process and methane production. The parameters found effective for completely breaking the algae cell are: detention time of 1 more or less 0.5 minutes, and minimum voltage and current of 65 Volts/285 ml and 3.9 Amps/285 ml, respectively

Investigations concerning the cellular response of tumor tissue to treatment with dimethyl sulfoxide and hematoxylin have not been reported. To establish the response of neoplastic tissue and cells to this combination of agents, this study was undertaken to determine the effects of dimethyl sulfoxide and hematoxylin on a transplantable lymphosarcoma in mice.

This dissertation includes 3 chapters which focus on algal bloom of the tidal fresh James River. The first chapter describes nutrient and light limitation assays performed on algal cultures and draw conclusions about long-term patterns in nutrient limitation by comparing results with a previous study . This chapter also describes the influence of riverine discharge upon nutrient limitation in a point-source dominated estuary. This chapter was published in Estuaries and Coasts (Wood and Bukaveckas 2014). The second chapter presents the first comprehensive assessment of the occurrence of the cyanotoxin Microcystin in water and biota of the James River. Data presented in this chapter show that bivalve grazing declines in the presence of Microcystin in the water. The chapter also describes feeding habits in fish as a predictor for inter-specific differences in Microcystin accumulation in their tissues. The work presented in this chapter was published in Environmental Science & Technology (Wood et al. 2014). The third chapter describes the fate of algal carbon in the James River Estuary and the importance of autochthonous and allochthonous sources of organic matter in supporting production of higher trophic levels. Here I draw upon ecosystem metabolism data (NPP and R), abundance and grazing estimates for primary consumers and estimates of advective losses of chlorophyll and external inputs of nitrogen to place ‘top-down’ effects in the broader context of factors influencing chlorophyll and nitrogen fluxes in the James. . This chapter also describes results from mesocosm experiments used to assess the influences of grazers on chlorophyll, nutrients and Microcystis. This work will be submitted in the summer of 2014 to the journal Ecosystems.