Pastoralist Way of Life Under Threat: : Assessing the vulnerability risks faced by pastoralist communities as well as their potential to adapt to climate change in the Horn of Africa

The aim of the thesis was to examine the main causes of pastoral  vulnerability to climate change as well as assess their adaptive capacity to withstand future climate disturbances in the Horn of Africa. By studying two of the most iconic pastoralists’ communities in Africa – the Somali and the Massai’s in Kenya, the study intended to use the communities as representative to the overall pastoralist’s situation in the Horn of Africa. The study used the 2007 IPCC Vulnerability Assessment framework that entails exposure, sensitivity and adaptive capacity to climate change as a guiding instrument to comprehend the complexities of the pastoral livelihood. The participants of the study included pastoralists, officials from the government, NGO’s and research Institutions. Major findings of this study were, in addition to climate manifesting in destructive forms, pastoralism faces political marginalization, shrinking pastureland, sprawling urbanization, exponential growth of population and conflicts. Despite the challenges, the study also finds strong adaptive capacity by the pastoralists. Adaptation strategies include traditional methods of rangeland management and migration. The study also shows new modern methods adaptation to climate mainly instigated by the pastoralists with assistance from external actors, these methods include; Ecological Based Adaptation and technology driven approaches as well as a mixture of agriculture and pastoralism – agro-pastoralism. It was also found that the two communities studied face different climate challenges and adaptation approaches

Computing nonsimple polygons of minimum perimeter

We provide exact and approximation methods for solving a geometric relaxation of the Traveling Salesman Problem (TSP) that occurs in curve reconstruction: for a given set of vertices in the plane, the problem Minimum Perimeter Polygon (MPP) asks for a (not necessarily simply connected) polygon with shortest possible boundary length. Even though the closely related problem of finding a minimum cycle cover is polynomially solvable by matching techniques, we prove how the topological structure of a polygon leads to NP-hardness of the MPP. On the positive side, we show how to achieve a constant-factor approximation