Mining-Influenced Water (MIW) poses major environmental issues in New Zealand and worldwide due to a legacy of unmitigated mining activities. As conventional MIW treatment technologies can be very costly in terms of chemical and energy inputs, cheaper and environmentally-friendly alternative remediation strategies have been developed. These so-called passive treatment technologies include a range of engineered systems relying on biogeochemical processes able to mitigate the acidity and to immobilize the metals in MIW. The present research, built on previous work conducted at the University of Canterbury, investigated the use of waste materials in mesocosm lab-scale sulfate-reducing bioreactors (SRBR) to treat actual mining-influenced water (MIW) sourced at an active coal mine in New Zealand. Specifically, this study investigated using waste mussel shells as an alkaline amendment (instead of the more conventional material limestone), with organic waste materials such as wood byproducts and compost in complex substrate mixtures in upward-flow SRBR. The influence of hydraulic retention times of approximately 3 and 10 days (HRT; i.e. the contact time between the MIW and the substrate mixtures in the SRBR) on the treatment performances was also evaluated. Overall, each system successfully treated the MIW (e.g. increased the pH > 6 and removed >78 % of the metals, except Mn) during the first 5-month treatment period, while during the second 5-month period, the treatment systems containing limestone and/or operating at a short HRT started to show signs of decreased efficiency. Generally, the system containing mussel shell and operating at a long HRT was constantly the most efficient system. Over the whole 41-week period of treatment, key metal removal efficiencies ranged between 97.6 and 99.7 % (Al), 83.9 and 95.2 % (Fe), and 9.2 and 38.8 % (Mn). Sulfate removal, in terms of moles of sulfate removed per cubic meter of substrate per day, was on average below the design values of 0.3 mol/m3/d, and ranged between 0.03 and 0.55 mol/m3/d (median values were 0.26 to 0.3 mol/m3/d during the first 5-month period but dropped to 0.094 to 0.1 mol/m3/d during the second 5-month treatment period). The SRBR containing mussel shell instead of limestone resulted in significantly higher alkalinity generation (between 32 to 85 % higher) and higher metal removals (between 0.6 % higher for Al and 14 % higher for Ni). These results were mainly attributed to the unique mineralogy of the mussel shell which comprises of aragonite with traces of calcite, while limestone comprises of pure calcite with traces of quartz. The statistical analyses showed that the sulfate reduction was not significantly affected by the alkalinity source. Similarly, systems operating at a longer HRT (10 days instead of 3 days) showed better treatment performances than systems operating at a short HRT in terms of alkalinity generation (44 to 62% higher), metal removal (between 0.5 % higher for Al to 15 % higher for Ni, and between 17 to 23 % higher for Mn), and sulfate reduction (50 to 77 % higher). Overall, the systems operation on a longer HRT were dominated by a more reduced environment facilitating the precipitation of metal sulfides, while the reactors running on a shorter HRT were constantly maintained out of equilibrium by the continuous addition of fresh MIW. Chemical and mineralogical analyses performed on the spent substrates suggested that the metals were removed through precipitation as, and adsorption onto, metal sulfides (Fe, Zn, Ni, Cu), (oxy)hydroxides (Al, Fe, Zn), and carbonates (Mn, Zn). Mn, a metal known to be harder to remove from solution was likely removed through the precipitation of rhodochrosite (MnCO3) and via adsorption onto the organic matter. These results generally corroborated the results obtained using the geochemical modeling PHREEQC. Overall, this study showed that mussel shells are not only a sustainable and effective alternative to mined limestone, but their use in SRBR would also result in a better treatment of MIW. Additionally, even though an increase in HRT resulted in a better contaminant removal, a HRT of approximately 3 days was sufficient to remove about 80% of all metals (except Mn). Therefore, the difficult choice of an optimal HRT must balance the need to meet a specific effluent quality while keeping the treatment time reasonably short, and an intermediate retention time of approximately 6 days could be optimal.

Zooarchaeological mussel shell assemblages can be affected by an array of biases, one of which is cultural bias. Cultural biases may be exhibited in the transport of mussels from nonlocal mussel beds, and/or in preferential taste. There are a few methods used to help determine if cultural biases are at play (e.g., nestedness and detrended correspondence analysis). This thesis aims to test a new method, the life history approach, to determine if it is a viable method for assessing cultural bias in prehistoric mussel assemblages from the Tombigbee River drainage. Shell assemblages from the drainage previously have been demonstrated to not be culturally biased; therefore, these assemblages will act as a control against which to test the life history approach as a method for cultural bias assessment.

A trial established in 2003 at Upper Moutere in Nelson, New Zealand, was used to evaluate the effect of mussel shells as reflective mulch on Vitis vinifera L. cv. Pinot noir vine performance and fruit and wine quality. Shell mulch had several effects on the environment and vine growth as well as grape and wine composition in the 2006/2007 season. Soil under mulch was cooler compared to un-mulched control, but buffered the extremes in temperatures. Fruiting zone temperature over shells was slightly higher during the day and cooler at night, showing no effect on mean hourly temperature. Shell mulch reflected greater amounts of UV-A, UV-B and PAR radiation into the fruiting zone. Shell reduced weed growth compared to control. Leaf petiole and blade samples showed higher amounts of calcium compared to control. Leaf SPAD values were higher in the shell treatment during veraison, previous and postharvest, but lower post budburst. While date of budburst was not affected by treatments, dates of flowering and veraison appeared to be slightly advanced over shells. Fruit set was similar between treatments and was considered poorer in shell bunches due to a larger population of seedless berries. Vine growth was not affected in terms of the number of nodes laid at pruning, flower cluster and shoot number pre shoot thinning, early shoot growth and lateral shoots development. Vigour was not increased by shells as demonstrated by pruning weights, canopy density and trunk circumferences being similar, though internode lengths in shell shoots were greater in 2007 and lower in 2006. Berry weights, bunch weights and vine yields were lower in shell than control, though greater berry numbers were recorded. There were slight differences between treatments in fruit and wine composition. Grape pH only varied in the middle of the sampling time, being higher the 2nd week and lower the 3rd week in shell grapes and TA was greater at harvest time. However, °Brix was only higher in shell grapes in the middle of the sampling period, being similar to control at veraison and harvest. Peduncle lignification was delayed at veraison as well as at harvest time. Shell must after crushing was greater in Brix but similar to control in pH and TA. Similarly, shell wines pre bottling showed higher alcohol and no differences for pH and TA. HPLC-DAD analyses of commercial-scale and microvin wines showed consistent differences of the individual flavonoid composition. Shell microvin wines were greater than control in quercetin and resveratrol. However, commercial shell wines were lower in epicatechin, gallic acid, resveratrol, and catechin than control. Leaf phenolic composition was also different between treatments. However, further analyses by HPLC-MS in wines as well as in leaves are necessary to identify individual compounds. Total anthocyanins and total phenolics were no different between treatments. Sensory analyses of microvin and commercial shell wines exhibited consistently lower levels of green and unripe tannins, and greater smoothness and complexity as well. Further analysis by GC-MS and HPLC-MS is warranted. Shell mulch improved sensory characteristics of the resulting wines.

This doctoral work was developed in the frame of bone tissue engineering, dealing with the fabrication of scaffolds for the regeneration of bones. At this purpose, calcium phosphates derived from natural sources are very interesting because they are more similar to the bone mineral and possess better bioactivity. Indeed, the bone mineral is different from synthetic hydroxyapatite as it is non-stoichiometric, nanosized, it presents a high degree of disorder and contains many additional ions and impurities such as CO32-, Mg2+, Sr2+, Na+, etc. These characteristics can be easily obtained by synthesizing hydroxyapatite from natural sources, such as corals, starfishes, seashells, animal bones, bird eggshells etc. The natural sources used in the present work are three types of biogenic calcium carbonate, i.e. calcium carbonate that is produced by living organisms in the form of aragonite or calcite. Among the different sources, three biogenic calcium carbonates were chosen: cuttlefish (Sepia Officinalis) bones, mussel (Mytilus Galloprovincialis) shells and chicken eggshells. Besides their abundance and availability, they were selected because of their different composition: aragonite in cuttlebones, calcite in eggshells and a mixture of aragonite and calcite in mussel shells. After the first chapter, which is a theoretical introduction, this thesis is divided into other five chapters. Chapter 2 contains a careful characterization of the three biogenic raw materials while Chapter 3 deals with the synthesis of hydroxyapatite starting from these natural sources. The process developed here takes place entirely at nearly room temperature, which allows the organic part of the biological materials to be preserved. This synthesis process is basically a wet mechanosynthesis followed by a mild heat treatment (up to 150°C). The study focuses on the influence of several process parameters on the synthesis efficiency: temperature, milling time, pH and raw material. The temperature used to dry the slurry after the wet ball-milling was found to be the most important parameter, the higher the temperature the faster the conversion of CaCO3 into hydroxyapatite. Moreover, aragonite was found to transform more easily into hydroxyapatite with respect to calcite, and also to follow a different reaction path. The synthesis process described in Chapter 3 allowed to produce different bio-derived powders that were found to be non-stoichiometric, nanosized, carbonated hydroxyapatites, containing also additional ions, especially Mg2+ in the eggshell-derived material and Sr2+ in the cuttlebone-derived one. These powders were then used as a starting point for the studies presented in the next three chapters. Chapter 4 shows a very preliminary evaluation of the interaction with human cells in vitro. First, the as-synthesized powders were consolidated by uniaxial pressing and sintering at temperatures between 900°C and 1100°C and their crystallographic composition was analyzed. Then, after having established the non-cytotoxicity of the sintered pellets, osteoblasts from human osteosarcoma cell line were seeded on the pellets and their behavior after 1, 3 and 5 days of culture was observed by confocal microscopy. In general, all materials promoted good cell adhesion and proliferation, especially the eggshell-derived one. At this point, the bio-derived materials were found to induce a good cellular response but, in order to foster the regeneration of bones, a scaffold must also contain a large amount of interconnected porosity. Among the numerous methods to fabricate porous structures, additive manufacturing is surely very attractive due many advantages, such as the possibility of customizing the shape based on tomography images from the patients, the fact that no mold is needed and the freedom of fully designing the porosity. Indeed, not only the size and the amount of porosity are important, but also the shape of the pores and their position and orientation have a deep effect on the interaction with the cells. Therefore, Chapter 5 and Chapter 6 deal with the fabrication of scaffolds by 3D printing, following two different approaches. In the study presented in Chapter 5, the powders synthesized from cuttlebones, mussel shells and eggshells were used in combination with a thermoplastic polymer (PCL, polycaprolactone) to obtain bioactive composites. Composite materials made of 85 wt% PCL and 15 wt% bio-derived hydroxyapatite were used to fabricate porous scaffolds by extrusion 3D printing. The biological in vitro tests showed that the composite scaffolds possess better bioactivity than the pure PCL ones, especially those containing mussel shell- and cuttlebone-derived powders, which promoted the best cell adhesion, proliferation and metabolic activity of human osteosarcoma cells after 7 days of culture. In addition, the elastic compressive modulus, which was found to be between 177-316 MPa, thus in the range of that of trabecular bone, was found to increase of about ∼50% with the addition of the bio-derived nanopowders. Finally, in Chapter 6, the cuttlebone-derived powder was used to fabricate porous bioceramic scaffolds by binder jetting 3D printing. Due to serious technical issues related to the printing of a nanosized powder, 10 wt% of bio-derived powder was mixed with a glass-ceramic powder with bigger particle size. Moreover, the organic part of the cuttlebone had to be previously eliminated by a heat treatment at 800°C. Thanks to the great freedom of design that is allowed by the binder jetting process, scaffolds with two different pore geometries were fabricated: with pores of uniform size and with a size-gradient. Indeed, natural bone possesses a gradient in porosity from the core to the surface, from porous trabecular bone to dense cortical bone. The sintered scaffolds showed a total porosity of ∼60% for the pure glass-ceramic and ∼70% for the glass-ceramic with 10 wt% of cuttlebone-derived nanoparticles, which most probably slowed down the densification by limiting the contact between the glassy particles. All the bioceramic scaffolds promoted good adhesion and proliferation of human bone marrow-derived mesenchymal stem cells in vitro, without any significant difference between the different samples. However, the scaffolds with the cuttlebone-derived powder and with gradient porosity showed the greatest decrease of metabolic activity after 10 days of culture, which could be accounted as a sign of differentiation of stem cells.

Kinlock is a freshwater mussel shell ring site located in Sunflower County in the Mississippi Delta. Little work has been done at freshwater mussel shell rings, and therefore little is known about them. This thesis uses four different data collection methods to answer questions of chronology, site layout, etc. These four methods are controlled surface collection, excavation, coring, and magnetometry. Based on the results of these methods, Kinlock was found to be a Woodland period mussel shell ring with a later Mississippian period component built on top of the shell. This later component consisted of five mounds situated around a plaza. It was also found that the plaza was planned and maintained from the Woodland period through the Mississippian period, until the site was abandoned.