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Humans play an interconnecting role in social-ecological systems (SES), they are part of these systems and act as agents of their destruction and regulation. This study aims to provide an analytical framework, which combines the concept of SES with the concept of tipping dynamics. As a result, we propose an analytical framework describing relevant dynamics and feedbacks within SES based on two matrixes: the “tipping matrix” and the “cross-impact matrix.” We take the Southwestern Amazon as an example for tropical regions at large and apply the proposed analytical framework to identify key underlying sub-systems within the study region: the soil ecosystem, the household livelihood system, the regional social system, and the regional climate system, which are interconnected through a network of feedbacks. We consider these sub-systems as tipping elements (TE), which when put under stress, can cross a tipping point (TP), resulting in a qualitative and potentially irreversible change of the respective TE. By systematically assessing linkages and feedbacks within and between TEs, our proposed analytical framework can provide an entry point for empirically assessing tipping point dynamics such as “tipping cascades,” which means that the crossing of a TP in one TE may force the tipping of another TE. Policy implications: The proposed joint description of the structure and dynamics within and across SES in respect to characteristics of tipping point dynamics promotes a better understanding of human-nature interactions and critical linkages within regional SES that may be used for effectively informing and directing empirical tipping point assessments, monitoring or intervention purposes. Thereby, the framework can inform policy-making for enhancing the resilience of regional SES.

Approximately 2.5 × 10 6 square kilometers of the Amazon forest are currently degraded by fire, edge effects, timber extraction, and/or extreme drought, representing 38% of all remaining forests in the region. Carbon emissions from this degradation total up to 0.2 petagrams of carbon per year (Pg C year −1 ), which is equivalent to, if not greater than, the emissions from Amazon deforestation (0.06 to 0.21 Pg C year −1 ). Amazon forest degradation can reduce dry-season evapotranspiration by up to 34% and cause as much biodiversity loss as deforestation in human-modified landscapes, generating uneven socioeconomic burdens, mainly to forest dwellers. Projections indicate that degradation will remain a dominant source of carbon emissions independent of deforestation rates. Policies to tackle degradation should be integrated with efforts to curb deforestation and complemented with innovative measures addressing the disturbances that degrade the Amazon forest.

Land ist eine begrenzte Ressource, und die steigende Nachfrage nach Lebensmitteln, Futtermitteln und Holz treibt den Wettbewerb zwischen verschiedenen Landnutzungsarten voran. Landnutzungsmodelle, die Landnutzungsmuster optimieren und negative Kompromisse zwischen verschiedenen Landnutzungen minimieren, können bei der Bewertung solcher Landkonkurrenzdynamiken helfen. Angesichts des langen Planungshorizonts der Forstwirtschaft ist die Modellierung der Dynamik des Forstsektors in einem einzigen Modell eine Herausforderung. Diese Dissertation zeigt, dass zwischen Land- und Forstwirtschaft auf feinen räumlichen Skalen (halbe Grad Gitterauflösung) ein Wettbewerb um Land besteht, und die Berücksichtigung eines dynamischen Forstsektors in einem rekursiven dynamischen Modell wie MAgPIE verbessert die Bewertung der Landnutzung und der damit verbundenen Emissionen. Die Speicherung von Kohlenstoff in seit langem bestehenden Infrastrukturen wie städtischen Gebäuden könnte eine zusätzliche Option zur Abschwächung des Klimawandels sein und gleichzeitig Hotspots der biologischen Vielfalt und Grenzwälder vor der Umwandlung in andere Landnutzungsformen schützen, zusätzlich zu den bereits gut verstandenen und quantifizierten landbasierten Abschwächungsoptionen. Auf diese Weise wird nicht nur Kohlenstoff über lange Zeiträume in den Holzstädten der Zukunft gespeichert, sondern es wird auch dazu beigetragen, Emissionen aus der Produktion von Zement und Stahl für den Bau von Infrastrukturen in der Zukunft zu vermeiden. Auf der COP26 wurde eine Erklärung zum Ende der Entwaldung bis 2030 abgegeben. Eine mögliche Politik zur Umsetzung dieser Erklärung vor Ort wäre das Verbot der Ausdehnung landwirtschaftlicher Flächen auf bewaldete Flächen. Dies würde bedeuten, dass nicht bewaldete Flächen in einem noch nie dagewesenen Ausmaß in landwirtschaftliche Flächen umgewandelt würden., Land is a limited resource and the increasing demand for food, feed and timber drives competition between different land use types. Land-use models, which optimize land-use patterns and minimize negative trade-offs across land uses, can assist in assessing such land competition dynamics. Given the long planning horizon of forest management and competition for land with agriculture, modeling forestry sector dynamics in a single model is challenging. The Inclusion of a dynamic forest sector in the Model of Agricultural Production and its Impact on the Environment (MAgPIE) helps in answering the overarching research question: What is the role of forestry in future land use? This dissertation shows that competition for land exists between agriculture and forestry on fine spatial scales (half degree grid resolution), and the consideration of a dynamic forestry sector in a recursive dynamic model like MAgPIE improves the assessment of land-use and its associated emissions. Understanding how production of roundwood influences the competition for land would help in quantifying how wood can be produced for timber cities of the future. Storing carbon in long-standing infrastructure like urban buildings could be an additional mitigation option, whilst protecting biodiversity hotspots and frontier forests from being converted to other land uses, on top of already well understood and quantified land-based mitigation options. This way, not only carbon is stored over long time spans in timber cities of the future, it also helps in avoiding emissions from production of cement and steel for construction of infrastructure in the future. Additionally, A declaration to end deforestation by 2030 was made at COP26. A potential policy implementing this declaration on the ground would be to prohibit the expansion of agricultural land into forested land. This would mean that non-forested land will be converted at unprecedented levels into agricultural land.