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The behaviour of carbohydrate metabolism in a plant, particularly its total starch content, total soluble sugar (TSS) content and their utilisation, is of great importance in coping with abiotic stress conditions. With this in mind, we studied total starch and TSS contents, survival, growth, biomass accumulation and stomatal conductance in Rhizophora mucronata under conditions of prolonged submergence and water stress for a period of 11 months. The experiment was designed in such a way as to include three replicates per each treatment level, about 1600 young mangrove plants being subjected to study in the process. Under conditions of prolonged submergence and high levels of water stress, a small number of mangrove plants survived and they were promptly exhausted due to higher starch utilisation rates (0.75-1.05% dry mass/month). Although TSS content was increased under these intense stress conditions, it was not matched by increased seedling growth or biomass production; instead, a significant reduction in growth (i.e., ~78%) and dry matter content was observed in stressed seedlings as compared to young plants in the respective controls. It follows that the intense increase of TSS content might be due to the direct conversion of starch to soluble sugars in order to produce metabolic energy for tolerance mechanisms like osmoregulation and root anatomical adaptations under stress conditions. This indicates that more energy is allocated for plant maintenance than for growth and biomass production under stress conditions, which might be a good acclimatory strategy to rescue young mangrove plants at the early phase. However, stomatal closure under stress conditions may have caused restricted photosynthesis. Therefore, stress-induced starch degradation may upsurge, which in turn might lead in the long-run to carbon starvation, a condition lethal to mangrove seedlings.

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In order to achieve collaborative action in nature conservation and natural resources management, stakeholders have to understand and acknowledge other stakeholders’ interests, values, world visions and objectives and they have to overcome the problem of irrational decision-making through innate opposition discourses. In this paper we developed the Mangal Play, an experiential learning method to have participants adopt the role of a particular stakeholder in an imaginary mangrove forest social-ecological system (SES). The Mangal Play is a serious game, more specifically a role-play, aimed at promoting oral dialogues between 20 stakeholders involved in governance, fisheries, aquaculture, agriculture, forestry, tourism, transport, conservation and communication sectors. By providing tools to lecturers and scientists to execute it in a public or classroom setting, the Mangal Play stimulates a decision-making process while accepting compromise and distinguishing bottom-line issues from negotiable positions, and instructs about the behaviour of complex real-world systems in a safe learning environment. We exemplify how social network analysis can serve to visualise the outcome and further develop the Mangal Play. In this way we hope to help stakeholders take into account diverse positions in a rational decision-making process.