Contribution to the development of mathematical programming tools to assist decision-making in sustainability problems

Abstract

Responding to the ongoing and emerging global sustainability challenges is crucial to promote a sustainable growth and development. Impacts and burdens of human activities are exceeding the Earth’s carrying capacity, overstepping the safe limits our planet sets, which may lead to abrupt or irreversible environmental changes. At the same time, the unstoppable growth of the world population will lead to increased demands as well as higher pressures on the environment. Without taking actions, issues such as climate change, environmental degradation or resources depletion may create unprecedented and perhaps irreversible situations that pose a serious threat to future human well-being and the environment. There is no doubt that a shift is needed for sustainability which calls for effective solutions when facing problems contributing to the transition towards a more sustainable development. Unfortunately, sustainability challenges often led to very complex problems, where many interrelated aspects and several conflicting stakeholder’s preferences have to be considered simultaneously, for which making good decisions become extremely difficult. In this regard, research-based information facing such problems may play an important role in decision and policy-making support to formulate adequate strategies and policies to accelerate the transition toward a sustainable future. This thesis is devoted to tackle different sustainability issues by developing systematic mathematical programming tools aiming at supporting the sustainable decision and policy-making which ultimately will lead to the development of more efficient mechanisms to foster sustainability. Against this background, there is a growing attention to the need for structural transformations in the way societies interact with the natural environment as the basis to reconnect the human development to sustained progress. In particular, this thesis focuses on two key transformations: the “food security transformation”, through decoupling the intensification of food production from unsustainable use of resources; and the “energy transformation”, supporting the shift towards an environmentally friendly economy. Regarding the former transformation, where agricultural sustainability has a key role to play, two mathematical programming models were developed aiming to foster more sustainable agricultural practises. With respect to the latter energy transformation, two models are proposed to support transition-makers to select and improve technologies, and to promote the collective actions so that forging ahead with an effective clean energy transition. Four major contributions are made in this thesis. First, a multi-objective tool is proposed to optimally allocate cropping areas considering simultaneously economic and environmental criteria. Second, a multi-period model is proposed to determine optimal cropping plans and subsidies to promote agricultural practices beneficial to the climate and the environment. Third, a novel data envelopment analysis methodology tailored to perform sustainability assessments is proposed, which allows comparing systems (e.g. electricity technologies) and also provides targets for improvement according to the extent to which they adhere to sustainability principles. Fourth, an optimised cooperative approach is proposed to promote and strengthen international cooperation in the fight against climate change. The capabilities of the four decision and policy making support tools developed in this thesis have been tested by applying them to real world case studies, therefore demonstrating that they could actually be used to support sustainable decision and policy-makers so that guiding us towards a more sustainable decisions. To sum up, this thesis provides sound systematic mathematical programming tools to support decision and policy-making on the path to sustainability, which are flexible and practical enough to contribute towards a more sustainable agriculture and a more sustainable energy future. Although there will be major sustainability challenges ahead, contributions such as those sought in this thesis, although apparently insignificant, may bring major strides in the transition towards a new era where the economy, society and the environment coexist as key pillars of sustainable development.