@article {4051, title = {Ecological research and management of intermittent rivers: an historical review and future directions}, journal = {Freshwater Biology}, year = {2015}, abstract = {

ABSTRACT: 1. Rivers and streams that do not flow permanently (herein intermittent rivers; IRs) make up a large proportion of the world{\textquoteright}s inland waters and are gaining widespread attention. We review the research on IRs from its early focus on natural history through to current application in management and policy. 2. The few early studies of the ecology of IRs were largely descriptive. Nevertheless, in the 1970s, synthesis of this sparse research complemented work on temporary standing waters to found a powerful framework for much of the subsequent research on IRs. 3. Research on the ecology and biogeochemistry of IRs continues to fuel our understanding of resistance and resilience to drying and flooding as disturbances. Syntheses of the growing literature, including cross-continental and cross-climate comparisons, are revealing the generality and individuality of ecological and ecosystem responses to flow cessation and surface water loss. Meanwhile, increasing numbers of experiments test the causality of these responses. 4. Much of the increased consideration of IRs in research, management and policy is driven by the observed and projected shifts in flow regimes from perennial to intermittent associated with changes in land and water use and climate, superimposed on the high incidence of natural intermittency. The need to protect and better manage IRs is prompting researchers to develop new or modified methods to monitor flow status and assess the ecological condition of these systems. 5. Intermittent river research and management will benefit from greater exploration of aquatic{\textendash}terrestrial linkages, wet{\textendash}dry cycling and temporal dynamics, more-detailed mapping and predictive modelling of flow intermittency and the application of metapopulation and metacommunity concepts alongside multiple-stressors and novel-ecosystems research. By building on existing knowledge, continuing to develop quantitative models and distribution maps and using experiments to test hypotheses and concepts, we can further ecological understanding and wise management of these ubiquitous ecosystems.

}, doi = {DOI:10.1111/fwb.12646}, author = {C. Leigh and A.J. Boulton and J. Courtwright and T. Datry} } @article {4049, title = {Invertebrate assemblage responses and the dual roles of resistance and resilience to drying in intermittent rivers}, journal = {Aquatic Sciences}, year = {2015}, abstract = {

ABSTRACT: Intermittent rivers are naturally dynamic ecosystems in which flow cessation and riverbed drying cause temporal fluctuations in aquatic biodiversity. We analysed datasets from intermittent rivers in different climate zones across the world to examine responses of aquatic macroinvertebrate assemblages to drying, in relation to both taxonomic composition and traits of resistance and resilience. First, we compared the differences in taxonomic richness and turnover and in trait diversity, richness and redundancy before and after intermittent sites dried with the differences in concurrently sampled perennial sites. We found such high levels of variation in the before-after differences at intermittent and perennial sites that we could not detect statistical differences between them. Second, we examined the effects of climate (arid, Mediterranean, temperate) and durations of dry and post-dry (flowing) periods on responses to drying at intermittent sites. Only climate had a detectable effect; the proportion of taxa at intermittent sites that persisted through drying-rewetting phases was greatest in arid-zone rivers. Regardless of climate, the invertebrates that persisted at intermittent sites were dominated by taxa resistant to drying. By contrast, taxa that persisted at perennial sites had fewer traits conferring resistance but more conferring resilience. The contributions of resistance and resilience combined with the presence of both intermittent and perennial reaches likely supports the long-term stability and persistence of communities in intermittent rivers, despite the inherently high variation in short-term responses to drying.

}, doi = {DOI:10.1007/s00027-015-0427-2 }, author = {C. Leigh and N. Bonada and A.J. Boulton and B. Hugueny and S.T. Larned and R. Vander Vorste and T. Datry} }