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Climate change is a major threat to biodiversity and ecologists have identified necessary adaptation strategies. However, little research has been conducted so far on the economics of climate adaptation for biodiversity conservation. Three challenges arise from an economic perspective: How to (1) assess the impact of climate change on the cost-effectiveness of conservation, (2) consider the increasing uncertainty, and (3) evaluate conservation policy instruments under climate change. Addressing these challenges provides a thus far largely unexplored perspective on the economics of biodiversity conservation. This perspective relies on novel methodologies and provides policy-relevant insights.
In this thesis, these challenges are addressed in eight articles. Chapter 2 presents a novel economic evaluation framework to assess policy instruments for climate adaptation. Specific criteria are developed, their relevance for different strategies is assessed and suitable instruments identified.
Chapters 3 and 4 have a methodological focus as two climate-ecological-economic (CEE) models are developed. Chapter 3 presents an applied model integrating detailed sub-models able to assess the cost-effective spatio-temporal allocation of conservation measures. In chapter 4, methods from operations research are developed further to identify optimal time series of reserve networks. In both chapters, cost-effective conservation plans are identified in case study applications.
In chapter 5, CEE modelling is applied to examine the role of uncertainties regarding future climatic conditions. It is found that a trade-off between expected performance and robustness emerges in the case study in the future.
In chapters 6 to 8, CEE modelling is used to assess policy instruments under climate change. Chapter 6 examines an agri-environment scheme: cost-effectiveness requires flexibility in adapting the timing of conservation measures due to species’ adaptations and changes in costs. Chapter 7 examines two versions of land purchase: a “no sale” policy which prohibits sales for ecological reasons and a “sale” policy to enhance spatial flexibility for adaptation. A new trade-off is identified: while “no sale” mainly increases habitat permanence of expanding habitat types, “sale” improves the outcome for increasingly threatened habitat types. Chapter 8 is novel in its comparative analysis of two policy instruments considering spatial and management flexibility in a case study. It is found that in the case study, conservation contracts are more cost-effective than land purchase, but that the relative suitability switches when the conservation agency is able to capture producer rents.
Finally, chapter 9 uses the results of chapters 3 and 5 to develop an innovative teaching tool for students to learn about cost-effective biodiversity conservation under climate change.
Wastewater treatment systems abound as a result of technological improvements in treatment processes. Therefore in the selection of a wastewater treatment system for a particular wastewater treatment situation there are many alternatives to choose from. Despite this development municipal wastewater treatment in communities in developing countries are not always sustainable due to the application of inappropriate treatment systems. The question is how can an appropriate treatment system be identified for a certain location? The answer to this question is of importance to developing countries where wastewater treatment is usually not sustainable.
In this study a framework for assessing wastewater treatment systems was developed. First, a comprehensive set of indicators representing parameters of treatment systems and properties of the study area that impacts on wastewater treatment were identified. Secondly, assessment of these indicators were carried out through expert and community survey to identify a final set of indicators whose composition consist of efficiency, reliability and simplicity of treatment systems and resource constraint, resource recovery and environmental concerns of the study area. Thirdly, four wastewater treatment systems, namely: Waste Stabilization Ponds, Trickling Filter, reed bed and free water surface Constructed Wetlands considered to be feasible for the study area were evaluated by the application of the identified indicators. Finally, a decision matrix produced was processed by multi-attribute decision making methods using two indicator weights to identify the most appropriate treatment system among the four alternatives.
Results of the study show that in a scenario where equal indicator weights are assumed, reed bed is identified as the most appropriate with stabilization ponds being ranked as the least appropriate. In a more practical scenario where the weights of the indicators are allocated to reflect conditions of the study area, free water surface is ranked as the most appropriate. This outcome is at variance with stabilization pond technologies currently installed at communities in the study area. The performance of constructed wetlands is at the midpoint as far as most of the high to medium weighted assessment indicators are concern. It therefore represents a compromising solution between waste stabilization pond and trickling filter. The study also shows a change in variants of constructed wetland with a change in indicator weights. An indication that the decision situation determines the appropriateness of a treatment system and not the treatment system itself.
The selection framework employed in this study can be said to be reliable and capable of identifying a treatment system that can be appropriate for a particular location. This is because the choice of a constructed wetland for the study area fits the definition of appropriate treatment system defined by the final indicators identified in this study.
Yemen is one of the most water-stressed countries in the world. The water deficit has been aggravated by the rapidly increasing demands for both surface and groundwater resources that are being unsustainably exploited. To address the country’s severe water scarcity, the government has adopted long-term intervention policies as stated in ‘Yemen's Strategic Vision 2025’. These policies are aimed at restoring the balance between water demand and availability, and at reducing the existing water deficit. Although 11 years have passed since this vision was adopted, the water deficit is still on the rise. The present situation raises questions about the efficiency of the intervention policies adopted by ‘Yemen's Strategic Vision 2025’ and about the effectiveness of implementing these policies. Another fundamental question pertains to the availability of a strategic assessment tool in the water resources sector that can be used to assess strategically future and current policies, strategies and plans, in order to ensure their efficiency in supporting water resources and in producing the positive impacts for which these strategic initiatives were developed in the first place. Strategic Environmental Assessment (SEA) is an assessment tool designed to function at a strategic level and help to bring aspects of environmental sustainability into the decisionmaking process. This research aims to demonstrate the potential of SEA in enhancing environmental sustainability in water policies for achieving sustainability of water resources in Yemen. In order to show the potential of SEA in the Yemeni water resources sector, this research has applied SEA methodologies and adopted a scenario-building approach for assessing the intervention policies adopted by ‘Yemen's Strategic Vision 2025’ to support augmentation of water resources. Qualitative and quantitative approaches have been used in this research. Quantitative historical data on water availability, water demand and water savings by interventions have been collected from the databases of national institutions and international organizations concerned. Statistical analyses have been used to project future trends until 2025. Qualitative analyses of relevant studies and reports covering the environmental, administrative, sociocultural and political-economic aspects of water resources management in Yemen have been implemented as well. In addition, 13 semi-structured key informant interviews have been conducted with decision-makers, managers and leading experts in the water and irrigation sectors. The research produced three future scenarios for the total water balance that may play out until 2025 in Yemen. These scenarios provide impact assessment and alternatives’ comparison of the existing intervention policies. The resulting scenarios are as follows: the ‘Business as Usual’ scenario, which forms an assessment of currently applied interventions and provides an image for the future, if current interventions are maintained at the same pace; the ‘Do-nothing’ scenario representing the situation if no interventions are implemented; and the ‘Sustainability’ scenario, which represents the potential future of the total water balance if existing interventions are to be scaled up and out. The findings confirm the significant potential of currently adopted intervention policies to support water resources. They also reveal that the current level of implementing the intervention policies has hindered the potential of these intervention policies in achieving the expected positive impact on the water balance by 2025. In order to achieve a significant decrease in the water deficit, the strategic quantitative targets that need to be implemented were identified. The methodology followed in implementing the research and achieving the findings demonstrates the potential of SEA in enhancing environmental sustainability in water policies for achieving integrated and sustainable water resources management in Yemen. The recommendations of the research covered improving the existing water balance as well as improving the assessment and planning context in the water resources sector. In order to improve the water balance situation, the research recommends implementing quantitative targets for water savings and augmentations, such as those developed by this research. These targets have been identified based on the capacities of sectors implementing these interventions. The research also recommends further decentralization of planning and management of water resources and the establishment of Water User Associations (WUAs) as the main vehicles for ensuring sustainable planning and management of water resources, including the scale out of interventions, subject to assessment in this research. In order to improve assessment and planning of water resources, the research recommends the adoption of SEA, the updating of water resources data and conducting regular assessments of policies, plans and programmes as part of monitoring their impact and providing a chance for amending these policies and strategies, if required, to achieve sustainability of water resources.
Stringent safety and environmental regulations, and competitions have challenged the chemical process industries to bring products to market at low lifecycle costs without compromising on safety and environmental standards. Frequently, a large number of alternatives with different structure design and process alternatives of distillation unit can be found to satisfy the demanded criteria of improvement target. Therefore, a systematic method for the improvement of distillation unit is of the considerable interest in order to evaluate the improvement objectives of design alternatives that include economic, environmental and safety criteria. Accordingly, this thesis presents integrated improvement of distillation unit based on careful and simultaneous evaluation of economic, environmental and safety criteria of the design alternatives. The approach for integrated plant improvement in this paper bears the consequence that economically attractive plant might not be the ultimate criteria as the decision tools to choose the best design, but put this economic criteria in a degree of preference in comparison to other criteria. Then, the evaluation of safety and environmental objectives in one side and total cost objectives in other side should be taken into account as a critical step in the plant improvement scenario. This research proposes a fundamental work on evaluation of economic, safety and economic criteria in distillation technology in an integrated manner. Economic evaluation will be calculated based on total annualized cost calculation. Environmental evaluation relies on the calculation of potential environmental impact associated with generated heat and mass balances generated by process simulation. Safety evaluation will be based on dynamic simulation of the investigated distillation unit during disturbance or non-standard operation as well as inherent safety index calculation. At the end, this thesis proposed a methodology for the improvement of distillation unit based on a framework of multi criteria decision making analysis. An analytic hierarchy process methodology is used to support decision upon the criteria for selection, rate the relative importance of the criteria and its advantages/ disadvantages as well as to combine the ratings to obtain an overall rating for each choice of design improvement. The concept will be applied in an existing plant as case study. It is supposed that the proposed integrated-scenario is applicable to support a decision making in chemical industries that always deal all the time with improvement tasks.