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AbstractBioenergy projects can lead to direct and indirect land use change (LUC), which can substantially affect greenhouse gas balances with both beneficial and adverse outcomes for bioenergy's contribution to climate change mitigation. The causes behind LUC are multiple, complex, interlinked, and change over time. This makes quantification uncertain and sensitive to many factors that can develop in different directions—including land use productivity, trade patterns, prices and elasticities, and use of by‐products associated with biofuels production. Quantifications reported so far vary substantially and do not support the ranking of bioenergy options with regard to LUC and associated emissions. There are however several options for mitigating these emissions, which can be implemented despite the uncertainties. Long‐rotation forest management is associated with carbon emissions and sequestration that are not in temporal balance with each other and this leads to mitigation trade‐offs between biomass extraction for energy use and the alternative to leave the biomass in the forest. Bioenergy's contribution to climate change mitigation needs to reflect a balance between near‐term targets and the long‐term objective to hold the increase in global temperature below 2°C (Copenhagen Accord). Although emissions from LUC can be significant in some circumstances, the reality of such emissions is not sufficient reason to exclude bioenergy from the list of worthwhile technologies for climate change mitigation. Policy measures to minimize the negative impacts of LUC should be based on a holistic perspective recognizing the multiple drivers and effects of LUC.This article is categorized under: Bioenergy > Economics and Policy Bioenergy > Climate and Environment

As a new form of regional multilateralism, the Belt and Road Initiative is China’s most significant strategic move for external engagement in international economic law, following its World Trade Organization accession. This paper analyses China’s approach towards the Belt and Road Initiative from a legal perspective, focusing on three questions: first, what is the proper scope of the Belt and Road Initiative? Second, is there an identifiable approach that China adopts in the Belt and Road Initiative context, and, if so, what is its key legal characteristic? Third, is China’s Belt and Road Initiative approach sustainable? Employing a functional approach in defining the Belt and Road Initiative, the article identifies three qualities to China’s approach to the Belt and Road Initiative: (i) that it is a hub-and-spoke network, (ii) it adopts a three-track institutional and mechanism approach, and (iii) a dual- track normative approach. Compared with the US trade approach (particularly the US–Mexico–Canada Agreement), these qualities reveal the key characteristic underpinning China’s Belt and Road Initiative approach: maximised flexibility regarding institutions and norms to address uncertainties and challenges in the Belt and Road Initiative. Such flexibility will likely assist in ensuring that China’s Belt and Road Initiative approach is sustainable by enabling trial-and-error, if properly managed. However, it also gives rise to concerns around China’s Belt and Road Initiative approach, especially as to its predictability, coherence, and transparency.

The primary question explored by this thesis is what alternative, carbon tax or emissions trading, would be an optimal policy for climate change mitigation in Australia. This thesis focuses on assessing carbon tax and emissions trading policy options on the basis of multiple criteria related to climate change policy in the Australian context. The study analyses the issues of environmental degradation, policy responses to the climate change issue, carbon taxation and emissions trading as a theoretical foundation for addressing the research question. The weaknesses of common evaluation methods and practices in dealing with climate change policy are also critiqued. After reviewing policy evaluation methods, the study builds a methodological framework to assess the climate change policy options based on the multi-criteria and Delphi methods. To facilitate the evaluation procedure, the criteria necessary for the climate change policy evaluation are identified. This study employs the Delphi method to verify the evaluation criteria in the Australian context and to assess the relative importance of these criteria. The thesis also attempts to construct carbon tax and emissions trading policies for Australia using a combination of theoretical and practical considerations. Further, these two contrasting policies are qualitatively analysed with reference to the identified criteria to assess potential performance of the proposed carbon tax and emissions trading. The resultant evaluation criteria and performance ranks of each proposed policy option allows building a decision matrix which facilitates the final evaluation and selection of an optimal policy. The evaluation results reveal that the carbon tax policy constructed by this study outperforms the designed emissions trading in terms of many criteria. As a result, the carbon tax is identified as an optimal climate change mitigation policy for Australia. The results of this study also indicate that the emissions trading proposed by the Australian Government might be a misleading policy founded on biased assumptions. Based on these findings it is recommended that Australia reconsider carbon tax and emissions trading policies on the basis of well developed multiple criteria to obtain a justified and sustained policy solution.

Climate change is undeniably the most urgent issue facing humanity. While the Paris Climate Agreement made progress in bringing about international collaboration, for Australia, outcomes at the national level remain uncertain. Nevertheless, the growing involvement of local governments in climate action is encouraging. Not only are the impacts most keenly experienced at this level, there is greater opportunity for control. This is particularly so as a range of non-climate-related co-benefits of climate change mitigation are available at this level. These co-benefits motivate governments to frame climate change mitigation in a positive light to operationalise broader economic, social, health and environmental benefits of low-carbon policies within the concept of sustainable development. Despite substantial evidence for co-benefits, their policy impact remains limited and under-developed. This thesis investigates local governments’ understandings of the ‘co-benefits approach’ in planning for climate change. It provides a systematic understanding of local policy context to plan, generate and purposively integrate co-benefits into the policy-decision-making processes. A methodology was developed to analyse the use of co-benefits in local government climate-related policies in New South Wales from July 2015 to May 2016. Investigation comprised three phases: a targeted on-line survey; review of councils’ climate-related policies; and in-depth interviewing of council officers. The on-line survey provides an informative overview of the factors that drive local action on climate change. The narratives generated from the interviews take this further revealing in-depth insights into policy-makers’ perceptions about the role of each factor, as well as an understanding of motivations for the uptake of co-benefits in policy. The thesis found that climate change mitigation is primarily driven by the dual objectives of reducing emissions and energy consumption. A focus on monetary considerations, together with constrained authority, policy and legislative support from higher levels of government, absence of data and know-how to assess co-benefits collectively, are key influences. As a consequence, most councils target only certain (quantifiable) benefits from ‘energy-related’ mitigation measures. This excludes significant health-related benefits. A broader policy direction from state to local government is required to facilitate adoption of a co-benefits framework by local government. This will enable councils to more readily consider non-climatic and non-energy-related benefits of low carbon measures. This thesis contributes a clearer understanding of local governments’ current use of the co-benefits approach in tackling climate change. This will help to purposively consider, plan, generate and promote co-benefits in planning for climate change in Australia by decision-makers.

Lignocellulose biomass derived from plant cell walls is a rich source of biopolymers, chemicals, and sugars, besides being a sustainable alternative to petrochemicals. A natural armor protecting living protoplasts, the cell wall is currently the target of intense study because of its crucial importance in plant development, morphogenesis, and resistance to (a)biotic stresses. Beyond the intrinsic relevance related to the overall plant physiology, plant cell walls constitute an exquisite example of a natural composite material that is a constant source of inspiration for biotechnology, biofuel, and biomaterial industries. The aim of the present review is to provide the reader with an overview of the current knowledge concerning lignocellulosic biomass synthesis and degradation, by focusing on its three principal constituents, i.e. cellulose, hemicellulose (in particular xylan), and lignin. Furthermore, the current industrial exploitation of lignocellulose from fast growing fibre crops (such as hemp) is highlighted. We conclude this review by suggesting approaches for further research to fill gaps in our current knowledge and to highlight the potential of biotechnology and bioengineering in improving both biomass biosynthesis and degradation.

Abstract China has dominated the global aluminum production and consumption in the past few decades, therefore it is of particular interest to stakeholders in China and worldwide to explore whether such aluminum boom will continue or not in China. This study applies a scenario-based dynamic material flow analysis to quantify the stocks and flows along the anthropogenic aluminum cycle in China from 1950 to 2100. Potential future changes of significant parameters are explored and identified, and around 250 sets of scenario results (including all flows, stocks, and losses along the aluminum cycle in China) are obtained for the comprehensive scenario analysis. The main findings include: (1) China's primary aluminum production will peak at around 40 MMT (million metric tons) at around 2025, leading to the end of primary aluminum boom that started from the early 1990s; (2) Domestic aluminum demand will continue to increase to more than 40 MMT due to the growing accumulation of in-use stocks in meeting future societal needs; (3) China's old aluminum scrap generation will increase dramatically (around 0.8 MMT per year) soon and secondary production will account for more than 60% of aluminum production after 2050s in almost all scenarios. Thus, there will be a rapid shifting in production capacity from primary to secondary routes. In this context, the corresponding policy should focus more on the urban mining, and improvement of end-of-life management systems and sorting technologies. These scenario results also reveal key opportunities and barriers in the process. Notably, it becomes increasingly important for China's and the global aluminum industry to investigate China's future role in the global market of primary and waste aluminum products.

Australia is the largest per capita greenhouse gas emitter in the developed world. If it seeks to effectively contribute to its share of global climate change mitigation, it must make a transition from fossil fuels to renewable energy technologies and energy efficiency. Bioenergy is one renewable energy technology that could help to reduce Australia’s greenhouse gas emissions. Apart from being a low-carbon alternative to fossil fuels when it is produced in an environmentally sound way, it offers many other advantages. The Darling Downs, in south-east Queensland, is a large agricultural and energy-producing region, making it a suitable case study for examining the biophysical impacts of replacing fossil fuels with bioenergy alternatives. Stocks and flows modelling is ideally suited to this, as it allows for future alternative scenarios to be created that also examine the effects of the transition on various sectors of the economy. This thesis develops three scenarios to examine the impact of transitioning from fossil fuels to bioenergy on the Darling Downs. First, the base-case or reference scenario reflects current agricultural practices and energy generation. Second, the ethanol scenario involves the construction of four additional first-generation ethanol facilities. Even though it reduced the need for foreign fuel imports, thereby contributing to energy security, the feedstock requirements were beyond the production capacity of the Darling Downs making it untenable considering the importance of grain production within the region and concerns about sustainability/land use change. Third, the electricity scenario involves replacing coal partially or totally with biomass in the two existing coal-fired power stations in the region. Only this scenario saw a large decrease in greenhouse gas emissions; however, the large feedstock requirements resulted in a large decrease in grain production thereby requiring a level of cofiring between 10 and 100 per cent. It was also concluded that the expansion of bioenergy production on the Darling Downs would require modifications to the Large-scale Renewable Energy Target; the introduction of feed-in tariffs; increased support for bioenergy research and development; and the introduction of extension services for farmers to make it viable.

Methods for recovering raw materials from end-of-life solar panels were studied. A process for removing the hazardous element lead (Pb) in solar panels was also investigated. We achieved recovery rates of 80%, 79%, and 90% for Si, Cu, and Ag. We also achieved a removal rate of 93% for Pb. We immersed the cells in 5 M nitric acid solution under agitation at 200 rpm to dissolve the metals. We sequentially recovered Si, Cu, Ag, Al, and Pb. To recover Si, a process for removing the Al electrode and SiNx layer was required. LIX84-I and 150 g/L H2SO4 solution were used to respectively extract and strip Cu. The purity of Ag powder after reduction Ag2O was 99.7%. An electrolytic refining process increased the Ag purity to 99.99%. We were able to achieve a removal rate of 93% for Pb through neutralization and sulfurization.