M.P. McHenry

Potential use of algae for heavy metal bioremediation, a critical review

Algae have several industrial applications that can lower the cost of biofuel co-production. Among these co-production applications, environmental and wastewater bioremediation are increasingly important. Heavy metal pollution and its implications for public health and the environment have led to increased interest in developing environmental biotechnology approaches. We review the potential for algal biosorption and/or neutralization of the toxic effects of heavy metal ions, primarily focusing on their cellular structure, pretreatment, modification, as well as potential application of genetic engineering in biosorption performance. We evaluate pretreatment, immobilization, and factors affecting biosorption capacity, such as initial metal ion concentration, biomass concentration, initial pH, time, temperature, and interference of multi metal ions and introduce molecular tools to develop engineered algal strains with higher biosorption capacity and selectivity. We conclude that consideration of these parameters can lead to the development of low-cost micro and macroalgae cultivation with high bioremediation potential.

Soil Organic Carbon, Biochar, and Applicable Research Results for Increasing Farm Productivity under Australian Agricultural Conditions

The conversion of vegetative biomass waste to biochar (biologically derived charcoal) is a source of carbon (C) that can be used to increase the level of soil organic C (SOC) in agricultural soils. This review collates available research into the effects of biologically derived C species with respect to the direct and indirect effects on agricultural productivity and their potential for use in Western Australian agricultural systems. There is a growing requirement to quantify the effect of specific biochar applications for agroecological purposes and to verify biosequestered C for climate-change-mitigation activities. This work provides a review and assessment of safe biochar application rates and examines the present levels of scientific uncertainty surrounding the efficacy and reliability of applying biochar to soils in relation to crop productivity.

Carbon-based stock feed additives: a research methodology that explores ecologically delivered C biosequestration, alongside live weights, feed use efficiency, soil nutrient retention, and perennial fodder plantations.

There is considerable interest in reliable and practical methods to sequester carbon (C) into agricultural soils to both reduce atmospheric greenhouse gas concentrations and improve conventional productivity. This article outlines a research methodology to refine the efficacy and economics of using long-lived C species (biochars) as stock feed additives, produced from farm waste biomass, for ecologically delivered soil biosequestration, while generating renewable bioenergy. This article also draws attention to potential parallel outputs including annual feed use efficiency, fodder species expansion, soil nutrient retention, aquatic habitat protection, and forestry revegetation, using nitrogen-fixing perennial fodder plant species. A methodology to generate parallel results including standing fodder tree C sequestration, optimised production of Acacia spp. biochar, animal growth on high-tannin fodder with biochar feed additives, soil nutrient and stable C fractions, and economics of Acacia spp. bioenergy production. This form of research is contextually dependent on the regional agricultural production system, legislation, and surrounding ecosystem. Therefore, this article suggests the use of a scenario approach to include regionally specific levels of biochar integration with respect to the local prices for C, fossil fuels, meat and livestock, fertilisers, fodder, feed additives, water, renewable energy, revegetation and capital.

Hydro, tidal and wave energy in Australia

The three renewable energy technologies discussed in this paper are based on water, but differ markedly in terms of the size of the available potential resource, the maturity of the associated conversion technologies, the extent to which they have been exploited to date, and the current research effort being devoted to their future development. Hydro-electricity and tidal power are both very mature technologies. The exploitation of Australias relatively limited potential for hydro-electric development began over a century ago and the opportunities for further hydro-electric development are now very restricted. The countrys significant tidal power resources, on the other hand, have not been exploited for electricity generation to date, but continual assessment of the feasibility of tidal power projects has been undertaken over the past half century. Although Australia has large ocean wave energy resources, ocean wave energy conversion technology is not yet fully commercial and no commercial wave generation plants are operating in Australia. A small number of wave energy conversion devices, however, are at the pilot testing stage.

Hybrid microalgal biofuel, desalination, and solution mining systems: increased industrial waste energy, carbon, and water use efficiencies

This work reviews retrofitting new waste energy, carbon and water intensive technologies into existing industrial facilities (including electricity generators) to increase net energy, carbon, and water use efficiencies. The three applications reviewed are microalgal ponds consuming flue gasses and providing thermal power station cooling services, thermally driven membrane distillation desalination, and hydrometallurgical solution mining processes to indirectly remove water contaminants, and additional power station cooling. The aim of this work is to explore the unique challenge of site-specificity of retrofitting any or all of the reviewed technologies within existing facilities for commercial operations. The theoretical basis behind higher aggregated efficiencies is essentially vertical integration of infrastructure, energy, and material flows, reducing total costs, net waste, and associated potential environmental contamination. Whilst solution mining and some thermal desalination technologies are not necessarily new in isolation, new technical developments enable these technologies to use waste heat and waste water by operating in parallel with industrial facilities, and effectively subsidise microalgae biofuel water pumping and dewatering. This research determines three fundamental developments are required to enable wide-scale industrial co-located vertical integration efficiencies: (1) fundamental engineering, (2) monitoring system innovation, and (3) technology/knowledge transfer.

Geothermal energy in Australia

Although Australia is not usually associated with geothermal energy, it possesses significant amounts of both conventional (wet) geothermal and hot dry rock (HDR) geothermal resources. The countrys conventional geothermal resources are extensive, but are low temperature and are located in areas of low population density with the result that they are not used extensively for either electricity generation or for direct heating. Australias HDR resources, on the other hand, represent a world-class resource but have not been used to date because the technology for converting HDR resources into electricity is not yet fully commercial. The effort being directed towards exploring economically useful HDR resources and in the development of technology to convert this energy resource into electricity could make HDR resources an important part of Australias energy mix in the near future, but there are major barriers.

Integrating mine closure planning with environmental impact assessment: challenges and opportunities drawn from African and Australian practice

Abstract Best practice mine closure planning and environmental impact assessment (EIA) principles share many common features. This research examined how mine closure planning relates to, and can be integrated with EIA by comparing practice in eight African and Australian jurisdictions. Emphasis was placed on key challenges and opportunities associated with: institutional arrangements for mine closure planning; financial mechanisms for mine site closure and rehabilitation including abandoned/legacy mine sites; transparency of mine closure planning and financing provisions; and regulation of artisanal and small-scale mining activity. Data were gathered through document analysis, interviews and interactions with practitioners from Western Australia, Ghana, Kenya, Nigeria, Mozambique, South Africa, Tanzania and Zambia. Issues associated with mine closure planning and rehabilitation under existing arrangements and opportunities for improvement through existing EIA processes already in place in each jurisdiction are explored. All eight jurisdictions have appropriate regulatory provisions in place already, but implementation capacity remains a challenge. Opportunities for effective practice lie in using mine closure planning and EIA measures in an integrated fashion, avoiding duplication and enabling synergies in management to be realised.

Linking restoration outcomes with mechanism: the role of site preparation, fertilisation and revegetation timing relative to soil density and water content

Global land use and ongoing climate change highlight the importance of ecological restoration as an emerging discipline and underscore the need for successful revegetation techniques. To link mechanistic drivers of seedling establishment with techniques to increase revegetation success, we undertook field-based experiments in degraded peri-urban woodlands in Mediterranean southwestern Australia using two iconic tree species. Over the course of an entire growing season, our objectives were to: (1) characterise soil moisture profiles in relation to site preparation techniques (ripping and created ashbeds) and (2) determine whether early seedling establishment can be increased through site preparation techniques (ripping and ashbeds), plant treatments (various fertilisers and biochar) and early planting during the wet season. Ripping significantly reduced soil compaction and was associated with a significant soil moisture stratification; moisture penetrated to greater depths in soils that were ripped or treated with ashbeds. Particular site preparation techniques (ripping) and early planting significantly increased early establishment, health and growth of tree seedlings. Fertilisation effects varied by species with generally neutral effects on seedlings. Finally, seedlings planted in ripped soils had significantly longer, deeper root systems accessing portions of the soil profile with higher summer moisture. Techniques such as ripping, even in deep sandy soils, reduce soil compaction and alter moisture availability within the soil profile, promoting deeper root growth and thus increasing revegetation success in these degraded Mediterranean ecosystems. Linkage of revegetation outcomes with plant response and physical soil properties associated with particular treatments provides critical knowledge for both restoration scientists and land managers.

Aeta Magbukún of Mariveles: Traditional Indigenous Forest Resource Use Practices and the Sustainable Economic Development Challenge in Remote Philippine Regions

The Aeta Magbukún of Mariveles are one of the least known and researched Indigenous peoples remaining on the fringe of the bay, and within the remaining forests in Bataan province on Luzon Island in the Philippines. This work describes the unique cultural systems and language of the Aeta Magbukún tribe in Biaan, Mariveles, and both the traditional forest resource use and the evolving new subsistence practices developed to adapt to the encroachment of non-Indigenous peoples onto ancestral lands. The Aetas forest resource use practices are discussed from a sustainable Indigenous development context within unique socioeconomic, cultural, and environmental circumstances in Bataan.

Critical elements in implementing fundamental change in public environmental policy: Western Australia’s mine closure and rehabilitation securities reform

ABSTRACT Development of public policy is a key role of government. Following the framework for Australian governments to uphold when developing public policy alone will not guarantee good policy development. This research critically explores the policy development process of the Department of Mines and Petroleum in Western Australia for mine closure and rehabilitation securities reform, where significant costs for mining companies, and large environmental and community legacies were at stake. Fundamental change from use of individual bonds to a central Mining Rehabilitation Fund resulted; offering financial advantage for mining companies and government alike, and a mechanism for rehabilitation of historically abandoned mines. Critical elements in the policy development process were: (1) openness in clearly articulating the policy problem at the outset, (2) retaining focus on the policy scope relevant to the jurisdictional level, (3) use of trusted experts especially for contentious aspects of the reform agenda, (4) commitment to stakeholder engagement throughout, and (5) acknowledging and managing uncertainties through transparent and consultative data gathering processes. Attention to these matters enabled an innovative and effective mine closure and rehabilitation policy solution to be implemented by the Government of Western Australia that is unique in Australia, and perhaps the world.