In situations of water scarcity, significant conflicts can arise between management of water for irrigation and inland fisheries. This paper considers the principles and lessons that can be drawn from the application of a conflict resolution mechanism-a protocol for participatory impact assessment and management-to a situation of conflict in the dry zone of Sri Lanka. Key features of this protocol are: (i) genuine participation of stakeholders; (ii) integrated assessment and management of impacts of irrigation on fisheries; (iii) management of information and an informed decision-making process; and (iv) adoption of an iterative and learning approach. The two main sources of conflict between fishermen and irrigators in the case investigated arise in the management of reservoir water levels and in the disposal of drainage flows into coastal lagoons. Application of the protocol demonstrated ways to improve information and communication between parties, to reduce conflict and to improve resource management. Consensus for resource management options was found in emphasising the priority needs of the poorest sections of local communities, and in seeking means to improve management of irrigation to the benefit of both farmers and fishermen. Application of the protocol thus identified possible synergies between irrigation and fisheries where previously these activities had been viewed as purely antagonistic. Copyright # 2004 John Wiley & Sons, Ltd.key words: inland fisheries; conflict resolution; impact assessment RÉ SUMÉ Dans les situations de pénurie en eau, d'importants conflits peuvent survenir entre les acteurs impliqués dans la gestion de l'irrigation et les pêcheries continentales. Cet article examine les principes et les leçons qui peuvent être extraits de l'application d'une telle procédure-un protocole pour l'estimation et la gestion des impacts-à une situation conflictuelle dans la zone aride du Sri Lanka. Les caractéristiques essentielles du protocole sont: (i) la véritable participation des parties prenantes; (ii) l'estimation et la gestion intégrées des impacts de l'irrigation sur les pêcheries; (iii) la gestion de l'information et un processus de prise décision elle soutenu par l'information; (iv) l'adoption d'une méthode itérative d'apprentissage. Dans le cas étudié, les deux principales sources de conflit entre pêcheurs et irrigants proviennent de la gestion des niveaux d'eau dans les réservoirs et de l'afflux des eaux de drainage dans les lagunes. En améliorant l'information et la communication entre les parties prenantes, le protocole a permis de réduire les conflits et d'améliorer la gestion des ressources. Un consensus a été trouvé dans les alternatives de gestion mettant l'accent sur les besoins prioritaires des catégories les plus pauvres des

This study, supported by the Challenge Program Water and Food (CPWF-Project 35), demonstrates the case of multiple-use of water through seasonal aquaculture interventions for improved rice-fish production systems in the Bangladesh floodplains. The project focused on community-based fish culture initiatives, increasingly adopted in the agro-ecological zones of the major floodplains of the Padma, Testa, and Brahmaputra basin. The productivity of water and fish is used as an indicator to explain this case. We hypothesize that seasonal aquaculture supported by the management of floodplains for multiple-use of water can significantly increase the productivity of rice -fish systems. Recognizing the need for innovative ways to manage human-dominated landscapes and climate-sensitive ecosystems such as floodplains, we have analysed seasonal aquaculture interventions along with local adaptation of water management strategies, including the consideration of groundwater mechanisms. The results, supported by quantitative analysis and qualitative arguments, demonstrate the significant contribution of seasonal aquaculture in improving the rice -fish production systems of the selected floodplain sites. This was achieved through the increased productivity of water and fish and the reduction of the risk posed by arsenic contamination. The study is also illustrative of the diversification in livelihood-generating activities to cope with the extended period of flooding cycle in the region. We highlight the value of multiple resource-use approaches to enhance the social and ecological resilience of floodplains, and the need to re-consider basin water management options to recognize the water requirements of other sources of food such as fish produced by capture fisheries and aquaculture.

This paper sets the stage for this Special Issue covering a set of papers, which try to provide a cross-scale evaluation of the trade-offs and synergies evident among aquaculture, water quality and environment in the empirical context of 8 different countries from Asia and Africa. Having discussed the livelihood and policy significance of the issue of cross-scale trade-offs and synergies, this paper provides an eclectic review of literature to show how this issue has been insufficiently treated in past studies. With a brief overview and synthesis of the papers included in this Issue, this paper also indicates how they overcome the analytical, methodological, and data challenges so as to provide a cross-scale evaluation of the trade-offs and synergies in different empirical settings. After illustrating how the new research insights can be integrated into the public debates and policy processes, this paper concludes with the identification of future research and policy needs.

The ecosystem setting of both agriculture and water provides a conceptual framework for managing the needs of agriculture for water and the impacts of water upon agriculture. Water underpins all benefi ts (ecosystem services) that ecosystems provide, including all agricultural production. The availability of water, in terms of both its quantity and quality, is also infl uenced heavily by ecosystem functioning. Understanding this relationship of water, ecosystems and their services with agriculture is at the heart of understanding, and therefore managing, water and food security. There are opportunities to move beyond seeing the agriculture-ecosystem-water interface as one of confl ict and trade-offs, towards simultaneously achieving both increases in sustainable food production and improvements in the delivery of other ecosystem benefi ts by agriculture through more widespread adoption of ecosystem-based solutions. These concepts and approaches are explained briefl y here as an introduction to understanding the interlinkages between ecosystem services, water and food security in subsequent chapters of the book. *