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Integrated water resources management (IWRM) and adaptive management (AM) are two institutional and management paradigms designed to address shortcomings within water systems governance; the limits of hierarchical water institutional arrangements in the case of IWRM and the challenge of making water management decisions under uncertainty in the case of AM. Recently, there has been a trend to merge these paradigms to address the growing complexity of stressors shaping water management such as globalization and climate change. However, because many of these joint approaches have received little empirical attention, questions remain about how they might work, or not, in practice.Here, we explore a few of these issues using empirical research carried out in Brazil. We focus on highlighting the potentially negative interactions, tensions, and trade-offs between different institutions/ mechanisms perceived as desirable as research and practice attempt to make water systems management simultaneously integrated and adaptive. Our examples pertain mainly to the use of techno-scientific knowledge in water management and governance in Brazil's IWRM model and how it relates to participation, democracy, deliberation, diversity, and adaptability. We show that a legacy of technical and hierarchical management has shaped the integration of management, and subsequently, the degree to which management might also be adaptive. Although integrated systems may be more legitimate and accountable than top-down command and control ones, the mechanisms of IWRM may be at odds with the flexible, experimental, and self-organizing nature of AM.

SUMMARYDuring development, extracellular signaling molecules interact with intracellular gene networks to control the specification, pattern and size of organs. One such signaling molecule is Hedgehog (Hh). Hh is known to act as a morphogen, instructing different fates depending on the distance to its source. However, how Hh, when signaling across a cell field, impacts organ-specific transcriptional networks is still poorly understood. Here, we investigate this issue during the development of the Drosophila ocellar complex. The development of this sensory structure, which is composed of three simple eyes (or ocelli) located at the vertices of a triangular patch of cuticle on the dorsal head, depends on Hh signaling and on the definition of three domains: two areas of eya and so expression -the prospective anterior and posterior ocelli -and the intervening interocellar domain. Our results highlight the role of the homeodomain transcription factor engrailed (en) both as a target and as a transcriptional repressor of hh signaling in the prospective interocellar region. Furthermore, we identify a requirement for the Notch pathway in the establishment of en maintenance in a Hh-independent manner. Therefore, hh signals transiently during the specification of the interocellar domain, with en being required here for hh signaling attenuation. Computational analysis further suggests that this network design confers robustness to signaling noise and constrains phenotypic variation. In summary, using genetics and modeling we have expanded the ocellar gene network to explain how the interaction between the Hh gradient and this gene network results in the generation of stable mutually exclusive gene expression domains. In addition, we discuss some general implications our model may have in some Hh-driven gene networks.

This article examines the implementation of integrated water-management institutions in the Paraíba do Sul River basin in southeast Brazil. It argues that social learning has been critical in facilitating reform implementation so far, and will likely continue to be an important factor for the future sustainability of the new management system. There has been a synergistic relationship between social learning and Brazil's water-reform hybrid governance institutions, in which social learning facilitated the implementation of the reform's new institutions, which in turn enabled further learning in the context of the river basin committee's decision-making process. Through interviews, surveys, and observations, we identified social-learning capacities, including trust, an ability to work together, and the committee's shared understanding of the institution's problems, possibilities, and mission. Effective management through social learning was demonstrated by the institution's adaptive capacity in the face of a severe drought.

Nations that border the Gulf of Mexico and Caribbean Sea are ideally placed for tracking the effects of global climate change and testing innovative ways to adapt to future changes.