in these ecosystems can easily result in widespread and severe land degradation and thus desertification. Combined with global issues such as climate change, economic disparities, migration, and competing claims on land, this often leads to a vicious cycle of aridity, land degradation, and productivity loss. In addition to the harsh environmental conditions limiting land productivity, the socio-economic situation in drylands can pose challenges as well, given that these regions are often characterised by remoteness, marginality, lowproductivity farming, weak institutions, and even conflict. Managing land sustainably under such conditions is a challenge which concerns land users and other stakeholders, policymakers, and researchers alike. Desertification research has traditionally focused on degradation assessments, whereas prevention and mitigation strategies have not sufficiently been emphasised, although the concept of sustainable land management (SLM) is increasingly being acknowledged (Chapter 1). The present research was embedded in the EU FP6 research project DESIRE (Desertification Mitigation and Remediation of Land – a Global Approach for Local Solutions; 2007–2012). DESIRE aimed to establish promising alternative land use and management strategies in 17 areas affected by land degradation and desertification around the world. Project work was based on close collaboration of scientists with local stakeholder groups. The study sites served as a global laboratory for developing and applying new methods of science – stakeholder collaboration and trialling traditional and innovative approaches to combating desertification. Chapter 2 offers a compilation and review of a number of methodological approaches to monitoring and assessing SLM which to date have been little reported in the literature. Lessons are drawn from these experiences, and common elements and future pathways are identified as a basis for a global approach. The local-level methods of the World Overview of Conservation Approaches and Technologies (WOCAT) framework serve to catalogue SLM technologies and approaches as case studies. This tool was included in the local-level Land Degradation Assessment in Drylands (LADA) as well as in the DESIRE project. Complementary site-based approaches can enhance an ecological process-based understanding of SLM variation. At national and sub-national levels, a joint WOCAT/LADA/DESIRE spatial assessment based on land use systems can be used to identify the status and trends of degradation and SLM, including causes, drivers, and impacts on ecosystem services. Expert consultation is combined with scientific evidence and, where necessary, enhanced with secondary data and indicator databases. Key lessons learnt include the need for a multi-scale approach, for using common indicators, and for drawing on a variety of information sources, including scientific data and local knowledge, by means of participatory methods. Methodological consistency allows for cross-scale analyses, and findings can be analysed and documented for use by decision-makers at various levels. Effective monitoring and assessment of SLM (e.g. for the United Nations Convention to Combat Desertification, UNCCD) requires a comprehensive methodological framework agreed upon and adopted by the major players. Although a variety of conservation measures are already applied at the local level, they are not adequately recognised, evaluated, and shared by land users, technicians, researchers, and policymakers. Likewise, collaboration between researchers and implementers is often insufficient. Chapter 3 presents a new methodological framework for a participatory process of appraising and selecting desertification mitigation strategies, and outlines first experiences from its application in the DESIRE project. The methodology – a key product developed within this PhD study – combines a collective learning and decision-making approach with the use of evaluated global best practices. It moves through a concise process in three parts, starting out with the identification of land degradation and locally applied solutions in a stakeholder workshop, followed by an assessment of local solutions using a standardised evaluation tool, and ending with the joint selection of promising strategies for implementation with the help of a decision support tool. A preliminary analysis of the application of the first part of the methodology showed that the initial stakeholder workshop resulted in a good basis for stakeholder cooperation and yielded promising land conservation practices for further assessment. Study site research teams appreciated the results, which they considered particularly valuable because urgent issues and promising options had emerged from joint reflection. The methodology was found to be suitable for initiating mutual learning among different stakeholder groups, as well as for integrating local and scientific knowledge. The thus identified SLM practices were then documented and evaluated by local researchers in collaboration with land users and using the internationally recognised and standardised WOCAT questionnaires. These in-depth assessments of 30 technologies and 8 approaches are analysed and compared across the DESIRE study sites in Chapter 4, highlighting key issues of SLM in drylands. Careful attention is paid to features which specifically characterise SLM in drylands and make SLM practices especially useful regarding the identified threats. Among the achievements attributed to the documented technologies, those mentioned most were diversified and enhanced production, as well as better management of water and soil degradation, whether by means of water harvesting, by improving soil moisture, or by reducing runoff. Demonstrating a favourable local-scale cost–benefit relationship was found to be crucial to improving people’s livelihoods and preventing further outmigration. However, it was also found that more research is needed to support the case study authors’ assessments of SLM impacts as well as to provide a solid rationale for investments in SLM. There are many and often competing options for SLM, and each must be assessed – and sometimes negotiated – prior to implementation. This makes SLM a classic multi-stakeholder issue which concerns individual and community land users, agricultural advisors, natural resource managers, government authorities, civil society, and researchers alike. Selecting appropriate SLM technologies for implementation thus requires an approach that is capable of integrating the diverse knowledge, perceptions, and judgements of the different stakeholders involved. Time and resource constraints often impede the development of contextualised, targeted, and sophisticated decision support systems. The DESIRE research project provided an excellent opportunity to develop and test a generic decision support methodology, using it to assist the study site teams in selecting, together with stakeholders in a stakeholder workshop, the most promising SLM option(s) for subsequent test implementation in the field (Chapter 5). Special attention was paid to the screening of local innovations, the selection and adaptation of potential SLM technologies, and the decision-making process determining which options are to be implemented. Chapter 5 reviews the application of the DESIRE decision support methodology in a variety of biophysical and socioeconomic contexts, finding it to be well-structured, comprehensive, and relatively easy to apply. The builtin global database of SLM options provided knowledge from various environments, while the use of simple software allowed for easy calculation and visualisation of results. The scoring and negotiation of each option’s sustainability forced stakeholders to consider and acknowledge each other’s positions and opinions, ensuring that the final choice was well-accepted. The methodology included seeking commitments from stakeholders to implement the selected option(s). Challenges included the complexity of the issues at hand and the need for skilled moderators. Nonetheless, positive outcomes and user feedback confirmed that the DESIRE decision support methodology is an easy-to-use stepwise methodology for facilitating decision-focused participatory processes. Participatory and multi-stakeholder approaches are increasingly motivated by social learning and empowerment goals. Yet there remains a lack of practical tools for facilitating such processes. The research presented here aimed to close the gap between the theory and the practice of stakeholder participation and learning in decision-making processes concerned with SLM. Chapter 6 analyses and describes how the 3-part participatory methodology for selecting SLM options contributed to multi-stakeholder learning. Cross-site analysis and in-depth evaluation of the Moroccan and Portuguese sites were used to evaluate how well the proposed process facilitated stakeholder learning and the selection of appropriate SLM options for local implementation. The structured nature of the process – starting with the joint setting of SLM goals – was found to facilitate mutual understanding and collaboration between stakeholders. The deliberation process led to a high degree of consensus over the outcome and, although this had not been an initial aim, in many cases also fostered social learning. This solution-oriented methodology is applicable in a wide range of contexts and can be implemented with limited time and resources. Chapter 7 presents insights into the field implementation of one of the selected SLM measures in Sehoul, Morocco. The Moroccan DESIRE study site was located near the city of Rabat, in an area where desertification poses a threat to marginal and often stony and degraded slopes. The use of marginal and stony land by the local population had become necessary due to increased poverty and the occupation of the best stretches of land by new owners. The land use change from grazing to cropping caused a deterioration of the field water balance, characterised by increased water loss through runoff, drainage, and evaporation, and resulting in less primary production. Promising experiences with no-tillage practices elsewhere in Morocco had motivated the Moroccan government to promote Conservation Agriculture throughout the country. This combination of crop rotation, minimal soil disturbance, and soil cover maintenance, however, had not yet been tested on sloping degraded land. The field trial results showed that covering the soil with crop residues neither improved yields nor increased rainwater use efficiency, although soil water was generally enhanced. Soil moisture measurements revealed that no-tillage was favourable mainly at soil depths of 5 cm and in connection with low-rainfall events (< 20 mm); under these circumstances, moisture content was generally higher under no-tillage than under conventional tillage. Moreover, farmers in Sehoul were found to be primarily interested in animal husbandry, and both crop residues and grains were used as feed. Chapter 7 concludes with lessons learnt from the on-farm trials in Sehoul. The synthesis (Chapter 8) offers more detailed reflection on certain key aspects of the research findings, such as the 3-part methodology, monitoring and assessment, stakeholder collaboration and learning, decision support, and desertification mitigation by means of SLM technologies and approaches. This is followed by a review of challenges and limitations of the proposed methodological framework and an assessment of its overall impact. The chapter concludes with an outlook and recommendations. One major conclusion is that research needs to move beyond simply idealising and promoting participatory approaches and learning processes: in addition, researchers must also advocate the provision of time and resources and the establishment of long-term partnerships by both scientific and policymaking bodies. Indepth and long-term field-based research remains important, but it requires sufficient resources and longterm commitment in order to provide adequate evidence. The methodology developed within this thesis is not limited to desertification; it is appropriate and useful for tackling land degradation anywhere in the world and for advancing towards more sustainable decisions on SLM strategies with a higher acceptance among stakeholders. Negotiation of, and deliberation over, ecosystem services might be the key to boosting SLM beyond the local scale, while at the same time compensating land users for their crucial efforts to combat desertification.