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Pervasive human impacts on urban streams make restoration to predisturbance conditions unlikely. The effectiveness of ecologically focused restoration approaches typically is limited in urban settings because of the use of a reference-condition approach, mismatches between the temporal and spatial scales of impacts and restoration activities, and lack of an integrative approach that incorporates ecological and societal objectives. Developers of new frameworks are recognizing the opportunities for and benefits from incorporating societal outcomes into urban stream restoration projects. Social, economic, cultural, or other benefits to local communities are often opportunistic or arise indirectly from actions intended to achieve ecological outcomes. We propose urban stream renovation as a flexible stream improvement framework in which short-term ecological and societal outcomes are leveraged to achieve long-term ecological objectives. The framework is designed to provide additional opportunities for beneficial outcomes that are often unattainable from ecologically focused restoration approaches. Urban stream renovation uses an iterative process whereby short-term ecological and societal outcomes generate public support for future actions, which may provide opportunities to address catchment-level causes of impairment that often exist across broad temporal scales. Adaptive management, education, and outreach are needed to maintain long-term public engagement. Thus, future work should focus on understanding how ecological and societal contexts interact, how to assess societal outcomes to maintain stewardship, developing new methods for effective education and outreach, and multidisciplinary collaborations. We discuss potential abuses and the importance of linking societal outcomes to long-term ecological objectives.

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International audienceNutrient-rich water bodies are usually expected to host low species richness at the local scale (water body). Nevertheless, they can support a diverse and sometimes unique biodiversity when diversity is considered at a regional scale. This discrepancy between the two scales is well documented for natural water bodies, but little is known about biodiversity of artificial water bodies, like fish ponds. We hypothesise that nutrient-rich water bodies can collectively host high species richness at the regional scale. Thus, these are important ecosystems for the regional conservation of biodiversity. We investigated 84 fish ponds in the Dombes region, France, with five taxonomic groups: macrophytes, phytoplankton, macroinvertebrates, dragonflies, and amphibians. Species richness patterns were determined for alpha- (single pond), beta- (between ponds), and gamma- (regional pond network) levels. For most studied species groups, richness per fish pond and at the regional level proved to be relatively high in comparison with natural ponds in other landscapes. Contribution of alpha-diversity to regional diversity was highest for dragonflies with 41 %, and lowest for amphibians and macrophytes with 16 and 18 %, respectively. For macroinvertebrate families and phytoplankton genera it was intermediate. Contribution of beta-diversity to regional diversity was similar for all species groups with 22-25 %. Furthermore, some ponds hosted a large number of less frequent species and some endangered species, indicating that the conservation of biodiversity of fish ponds must be established at a regional scale

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Summary Suitability of the local habitat (‘habitat filtering’) and dispersal between stream reaches determines the composition of insect communities, and urban land use may affect both processes. While urban streams are often poor habitats for insects and dispersal between them is often hindered, conservation and restoration activities generally focus solely on the local (in‐stream) environment. We determined whether in‐stream habitat filtering (a ‘local’ process) or dispersal between reaches (a ‘regional’ process) controlled assemblage composition in a landscape subject to ongoing urban development (‘urbanizing’). We compared models incorporating geographic distance between sites, environmental dissimilarity, and land‐use/land‐cover attributes of dispersal pathways in an attempt to explain the dissimilarity of stream insect assemblages. Distance and land‐use/land‐cover attributes were characterised along both overland (straight line) and corridor pathways. Both in‐stream habitat filtering and dispersal affected assemblage composition, but habitat had a stronger influence. Overland distance was a better predictor of assemblage dissimilarity than corridor distance, implying stream insect dispersal occurs across catchment boundaries as well as along stream corridors. The best model incorporated land‐use/land‐cover attributes along dispersal pathways, which supported the idea that urban land‐use in the terrestrial environment mediates dispersal. Conservation and restoration strategies for streams in urbanizing landscapes that focus on local habitat quality and ignore dispersal are missing a potentially important mechanism affecting insect assemblage composition. While the primary focus should be on maintaining or improving the local habitat, potential dispersal pathways should also be considered.